Sciences : histoire orale

Transcription : Arne Hessenbruch

Pour citer l'entretien :

« Entretien avec Bernhardt Wuensch », par Arne Hessenbruch, 9 January 2001 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article133.

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Entretien avec Bernhardt Wuensch, par Arne Hessenbruch, 9 January 2001

Lieu : Dibner Institute, USA

Support : enregistrement non précisé

Edition en ligne : Sophie Jourdin

WHITTINGHAM Stanley, 2000-10-30

Sophie Jourdin — 2011-11-11T22:33:28Z

Michael Stanley Whittingham is one of the main figures in the history of rechargeable batteries. From the late 1960s until now he has examined promising materials for use as cathode, anode, or electrolyte. He pioneered the use of titanium disulfide for cathodes, now commonly used. He also initiated the concept of intercalation. This term refers to the insertion of positively charged ions into the cathode material. In a rechargeable battery, Li+ ions are typically inserted between layers of the titanium disulfide cathode while the battery is being charged, and then de-intercalated during discharge. That the process of intercalation and de-intercalation of ions leaves the basic structure of the host material intact, so that the charge and discharge can take place repeatedly, was an understanding forged in the 1970s and early 1980s, and in which Whittingham played an important role. He has also been prominent in the field through the editing of its main journal, Solid State Ionics, from its inception in 1981.

Whittingham went into management for a number of years (1984-1988), while the field forged ahead. Japanese companies, in particular, made great strides in the commercialization of lithium titanium disulfide rechargeable batteries. When he rejoined battery research, the Japanese lead was becoming dominant, embodied in a raft of patents.

Since 1988, Whittingham has explored further materials with a view to improving batteries still further, both with regard to size and to performance. This will not change drastically the way in which the energy economy is currently organized (for example, the electrical vehicle is not around the corner), but smaller and more powerful batteries will impact upon the cost and design of portable electronics.

Biographie détaillée

STANLEY WHITTINGHAM (SW) : I graduated with a PhD in solid-state chemistry (from Oxford).

BERNADETTE BENSAUDE-VINCENT (BBV) : So you were trained as a chemist, mainly ?

SW : Yes.

BBV : And why did you go to Stanford, with Prof. Huggins ?

SW : Because in my time almost everyone from Oxford came to the States for one or two years. That was expected if you wanted an academic or an industrial job. It changed a lot... 1968. And why Stanford ? It was on the West Coast, California had sun.

BBV : And your PhD was on tungsten bronzes ?

SW : That's right : tungsten oxides and tungsten bronzes.

BBV : And how did you choose this topic ? It was not that popular ?

SW : No, I think Oxford always had a very active program in solid state. There were three or four faculty there interested in solid-state.

BBV : Who was that ?

SW : Peter Dickins was my advisor ; and J. S. Anderson was head of the department. And Jack Lunette was also there, and he was interested in the theory of calxes. So initially we were studying (?) catalytic activity, and how all that changed with the changes in the electronic properties of the material. There was a great deal of interest in the crystal structure, or rather the band structure, that controls the catalytical activity.

BBV : So it was mainly for catalysis in Britain ?

SW : Right. And we chose a very, very simple reactant : mainly oxygen atoms, and we just looked at how they recombine at the surface. And this was at the time of Sputnik and the US Air Force paid for the research.

BBV : Even the research conducted in Oxford ?

SW : They paid through their London office. Because they were interested in how various species (?) reacted outside their space ships.

BBV : So it makes sense in fact.

SW : Right. And that was the topic of my masters degree mainly. And then we looked at the same materials as catalysts potentially for gas production. And the Gas Council paid for that research. But within a few months of me starting the research, they struck natural gas in the North Sea.

BBV : And you stopped the project ?

SW : No, they said : we are not really interested in what you are doing anymore, but you have got the money. Do what you want and don't bother us too much.

BBV : And in those days money was easy to get ?

SW : Oh yes, you turned down money in those days.

ARNE HESSENBRUCH (AH) : You mean this was the case between the oil crisis and the discovery of natural gas in the North Sea ?

SW : No, they discovered gas in the North Sea before the 1973 oil crisis.

AH : Why did the money flow easily ?

SW : Well, the money came from the Gas Council and they made gas basically from coal. So they wanted a better catalyst to convert. Natural gas avoids all that messy stuff. The rest is really history. London cleaned itself up because they stopped burning coal.

BBV : And then, when you moved to Stanford who was there ? And how was the lab ?

SW : I worked for Bob Huggins there. And that was quite a switch. In England, France, and Germany, solid-state chemistry was a respectable subject. Chemistry departments did solid-state chemistry. In the US you could count the number of solid-state chemists on the fingers of one hand. So I went to a materials science department, not to a chemistry department.

BBV : Was Huggins considered a solid-state chemist ?

SW : He was a materials scientist with a PhD form MIT and he set up a new centre for materials research at Stanford. His interest was in solid-state electric chemistry ; how ions move in solids and things like that. And at that time the Ford Motor Company had just discovered that sodium ions move very fast in a material called beta-alumina. Sodium ions move almost as fast in that solid as they do in a liquid.

BBV : So it was the time of the beta-alumina ?

SW : Yes. Ford published their data in 1967, and I went to Stanford in 1968.

BBV : Did you continue your research on tungsten bronzes there ?

SW : Yes and no. I measured the conductivity of beta-alumina. That is what we tried to do. We has to have electrodes that were reversible to electrons, so we could get a current, and to the ions that were moving. So we paid attention to bronzes that had sodium in them, to metallic conductors, to see if they would make good electrodes. So we have narrowed the Oxford work into the Stanford work.

BBV : And how did you develop the batteries using tungsten bronzes.

SW : I arrived at Stanford in February. In May or June of that year Bob Huggins left to go to Washington to run this whole suite of advanced research centres of materials (?) of which MIT is the last surviving. So he went there and manned those for about two and a bit years. I remained at Stanford and continued my research on the basics. And about the same time, there were others in the medical field who were interested in batteries for pace makers and things like that and there was a number of good silver iodide conductors... (?). And it struck us that sodium or potassium had an advantage over silver because they yield a bigger current. And that is where we got the interest in actually using them. Beta-alumina as the electrolyte and we thought of sodium and some oxides as the electrodes.

BBV : And how did you come to your favourite, titanium disulfide ?

SW : Ah, that is a jump.

BBV : Yes, because you took the patent out in 1973.

SW : Right. While I was at Stanford a number of other people, in particular Hector Ball, who was Professor of Applied Physics and associated with the Materials Department. He was contacted to find people to go to Exxon who were starting up a new corporate research lab. Exxon really had very few chemists and physicists at the time. So I did an interview at Exxon and one at Cornell, and I was offered a job in the Materials Science Department at Cornell, not the Chemistry Department. About a third or a half of the faculty in Materials Science Departments in the US are physicists and chemiusts... they have PhDs in physics or chemistry, not in materials science.

BBV : Incidentally, do you think that physicists have had an impact on your field ?

SW : Oh yes. At Exxon they made me a very nice offer. What they had built up was an interdisciplinary group. It was led by Fred Gamble, who had also come from Stanford. His interest was in superconductivity. And that was the first wave of superconductivity. What we tried to do then was to look at (?) tantalum disulfides. And by intercalating different molecules between the sheets of tantalum disulfide we could change the superconductivity transition temperature. So, tantalum sulfide became superconducting, I think it was at 0.8 degrees Kelvin. By putting in different molecules you could raise it to about 6 Kelvin. It turns out that the one that could raise it the highest was potassium hydroxide. And my first job was to try to understand what was going on. And what I found out was that basically potassium ion structure was particularly stable in TaS2-... It behaved like a salt ... there was again of energy ... (?).

AH : Where was this new Exxon lab placed ?

SW : It was across the street from a refinery in Linden, New Jersey, along with a raft of other chemical and solids research labs. Basic research. And the goal was to be prepared since oil was soon going to run out. My part was energy-related systems, other than petroleum and chemicals.

AH : It was set up in 1972 and you were there from the very beginning ?

SW : It may have been set up in 1971, but basically yes.

BBV : How many people worked with you on this project ?

SW : The group headed by Fred Gamble : there was about six of us. Each one of us had a different background. Fred Gamble himself was something like a physical chemist, there was an organic chemist, some were physicists.

AH : Presumably you had plenty of funding for equipment and the like ?

SW : In those days, if you needed something for your research you asked for it, and it would be there in a week. Money was no issue. They invested in a research laboratory like they invested in drilling oil. You expect one out of five to pay off.

BBV : Was it perceived as a long-term project ?

SW : Yes.

BBV : And what did that mean : 10 years ?

SW : 5-10 years. Industry has changed considerably since then. I would say after about 7 years they began to ask : well, what is going to come out of this ? By that point we had moved from tantalum sulfide, which is really no superconductivity material. We were looking at lighter materials : titanium sulfide. And we were looking at lithium, not potassium, because it turns out that potassium is very dangerous. And some time in this period a Japanese company had come out with a carbon fluoride battery which they used for fish floats. They fish at night and they need to see where their floats are. And that was a primary battery. This was the beginning of interest in lithium batteries.

BBV : So the initial interest came from Japan ?

SW : Well... we thought we could do something better. It was a high-voltage, one-shot, then you throw it away. And Exxon was only interested in rechargeable systems. They were looking to the electrical vehicle.

BBV : From the very beginning ?

SW : As soon as we started. We were only in energy, but we told them that we may have a battery and they immediately jumped to the notion of an electrical vehicle. And they in fact built – well it must have been in the mid-1970s – a 3W and diesel hybrid vehicle running on the roads.

AH : Presumably the Japanese were also interested in the EV at this early stage ?

SW : No, they were not interested at all. In the mid-1970s some Japanese companies started selling calculators with solar systems built in.

AH : In other words, they focused only on smaller batteries than those employed for vehicles ?

SW : Yes. And it is important to make the point that no battery company came up with any inventions. Every invention coming from Japan came not from a battery company. They had a device they wanted to take to the market. Sony, Sanyo. It is a straight busines. They do not stray from where they have been.

BBV : And from where did you get your techniques in intercalation chemistry ? Did you receive training in this already in Oxford ?

SW : Well, the tungsten bronzes are quite similar in this respect sodium, lithium, or hydrogen in and out. There was interest in electrochromic displays in the late 1960s early 1970s and so we were all familiar with them. You have tungsten dioxide and you put in in acid adding a bit of zinc. It generates atomic hydrogen and turns into a solid going from yellow to blue.

BBV : Yes, but when the mixed conductors started, I think there was something of a change in intercalation chemistry.

SW : Yes.

BBV : Was there any feedback from your research at Exxon to intercalation chemistry ? Or was it isolated as a completely industrial research lab ?

SW : No, I think we had a huge impact. At the time Bell Labs were doing similar things. They were located close to us, they were a similar group, also with many individuals from Stanford. We were competing head-on for a while, also in publications. If you look at our publications on the battery, you will see a lot of basic science with no mention of batteries at all. Exxon clearly did not want to disturb their aura (?).

AH : What journals did you publish in ?

SW : Electrochemical Society, Materials Research Bulletin. But the electrochemical stuff came after the basic stuff. So much of the basic stuff went into the MRB which had a very strong reputation in those days.

BBV : So, you have been working on titanium sulfide for many years ?

SW : I started working on that when I joined Exxon in 1972, already in October. As soon as we started work on it we realized that it had very interesting physical properties. So my colleagues like Art Thompson ... (?). After a year we knew about that material than anybody in the world.

AH : May I ask a couple of questions about the early period before we get advance too far chronologically ? Would you please contrast the appearance of the labs at Oxford, Stanford and Exxon ?

SW : Sure. Oxford was an organic chemistry lab. We were in the old wing of the building, built probaly at the beginning of the last century. The walls are three feet thick. There was mercury all over the floor and under the floorboards. It was an antique place. But most of the facilities were there. It was all set up for solid-state work, because the head of the department was a solid-state chemist. We had some of the first NMR ... (?). It was, I would not say state of the art but, pretty good for those days. And what people don't realize is that there was no such thing as an electronic calculator. The computer we used took up a whole Victorian house and it had less power than one of those [pointing to a PC].

AH : What was your working day like ?

SW : If you were running an experiment you stayed there. There was no computer. If you were lucky you had a chart recorder. change temperatures... (?) You built your own equipment, you could not buy it.

BBV : Was the equipment different in Stanford ? Was it a shock ?

SW : Stanford was a new building. The Center for Materials Science had been built just a few years earlier. The building was new, most of the equipment was fairly new, though soime of it was surplus from (?). But the change was more going from a chemistry department to one of materials science. There were no fume hoods in the buildings. It was much more electronically oriented and obviuously the computers at Stanford were then better than those at Oxford. And after maybe a year there, a hand-held calculator costing about $95 came out. ..... (?)

BBV : And that was important for your own field ?

SW : Yes, because we wanted to measure how fast ions move. We made the first measurements over the first 5 or 10 seconds. You can do it with a chart recorder but it is very difficult.

BBV : And at Exxon ? Did you have everything you needed ?

SW : You had everything you wanted within reason. It was a new set-up and wanted to get it going right. Their attitude was that our time was much more expensive than the equipment.

AH : Were there more technicians at Exxon than the other two places ?

SW : No, I would say it was almost the opposite. Oxford had more support staff than any place in the US. We had a huge machine shop, a huge glass-blowing shop. And you had the old business of artisans in what were called shops. They would do new things for you, but they expected you to do anything routine by yourself. If it was complicated, they would do it for you.

AH : And in the US you would buy in ?

SW : Yes, there you tended to buy stuff. There was some support staff but nowhere near the same. These days there is almost no support staff.

AH : But the impact of the computer has generally speaking been more marked in later periods than the one we are talking about now, right ?

SW : Yes, when did the PC arrive ?

AH : I think it was about 1986.

SW : And I was at Exxon from 1972 to 1984. We came up with a battery patent early on. We had an incredibly good patent attorney. They would write up your invention and then ask you : why can't you do it this or that way ? And they came up with ideas for building a battery fully charged or fully discharged. TiS2 patent... (?)

BBV : And did you publish more patents or more articles during your time at Exxon ?

SW : More articles because one of the goals was to get Exxon better known as a research institution so they could hire better scientists. And there was some pride with the president of the company that he wanted to compete against Bell Labs. So he wanted us to be perceived as the labs of the energy business. One of the presidents was E.B. David (?) who subsequently became head of the board of Science Advisors or something like that. He wanted Exxon to be known as the best place in the world.

BBV : So they valued research over patents ?

SW : Both.

BBV : Was not there a tension between the two in the disclosure of results ?

SW : Yes. The publications did not mention batteries at all. So we made materials and we described how we made them. We then discussed their scientific behaviour, how they reacted with water, their thermodynamics. But anyone smart enough would know what we were doing. They soon caught on. And I think about 1975 or 1976 when the first patent started coming out we released the first paper in Science Magazine. And about the same time we also published ... (?). Because up to that time people in the battery business did not know what intercalation was. ...

BBV : Did you attend the Belgirate, Italy, meeting in 1973 that purportedly is the founding event of the community ?

SW : Yes, I gave two papers both of which went very well. And the other thing I remember is that Carl Wagner attended that meeting. He was very old. He basically put the field of corrosion on a scientific basis. He ought to have received a Nobel Prize.

BBV : Were there more Europeans there ?

SW : It was organized by Europeans, and I think there were more Europeans. And I remember that I was there with my wife and two young children. We bailed out half a day early because they said it was going to snow in the Alps, in order to go back to England.

AH : Were there any Japanese present ?

SW : Yes, I think there were a few.

AH : So you agree with the interpretation that this was a founding meeting ?

SW : Yes.

AH : One might also point to the beginning of the journal Solid State Ionics (1980) as the origin of a community ?

SW : Yes, but by that stage we were already having annual meetings.

BBV : Did the journal make any difference ?

SW : Do you want a bit of history of the journal ? The North Holland folks then had an office in the US. I lived in New Jersey two miles away from the publishing editor. They published the Belgirate proceedings. And this editor said : we need a journal in this field. I was one of those who said : no we don't.

AH : Why did you think that ?

SW : I thought there were too many journals already, even at that time. There were few compared with today of course, but even so. So he said, you prove that to us and we will pay you to do it. So Hans Becker (?) and I sent out a mail to everyone in the community, saying North Holland was going to start this journal and was there any interest ? I fully expected to get negative feedback hbut 95% wanted it. So North Holland played every nice game and we could not say no.

AH : Did the journal then not change anything much ?

SW : Yes, the journal changed a great deal because it pulled all the papers together in one place. Remember in those days there were no journals such as Chemistry and Materials. Solid-state chemistry had just started and that was more high-temperature. And there was the Materials Research Bulletin. So papers were all over the place. So they convinced us to go with it. I had my arm twisted to edit it. Within one year we went from single-column to double-column format and larger-size paper. It basically took off straightaway.

BBV : The whole community decided to publish in this journal instead of in the others you mentioned ?

SW : Yes. They kept publishing in other journals also, but they knew that here they would have their stuff recognized .

BBV : Was it a fast publication ?

SW : Five months. The goal was to get it out quickly. In those days the Materials Research Bulletin got things out in two months.

BBV : Let us come back to your career. Why did you leave Exxon in 1984 ?

SW : Exxon had one good thing about them. It was run by scientists and engineers, not by lawyers or MBAs. I will give you an example. When we had come up with the battery, the board of directors came to the lab to listen to us. And they then said here is the money, now go and do it. So they built an applied film group costing millions of dollars, a very good one. It was like a poker game : well we make a big dollar or we loose it. Their philosophy was that if you were a good scientist then you would also be a good director. So within a few years I became a lab director. I am not sure exactly when but at some stage they said : now you have shown that you can manage something you know, so we will now send you off to manage something you do not understand. That is why I went to an engineering facility, where I headed their chemical engineering. I was responsible for technology, for synthetic fuels in those days, chemical plants, raffineries. It sounded challenging at the time and I stayed there four years. At that time began the shale oil and coal gasification (?). It was a booming period. My job was to employ as many chemical engineers as I could lay my hands on. But soon the writing was on the wall and the slump was coming. We started laying off people. We went from roary-rosy days to (?). And I was doing no science myself then. I missed that and that is why I went to Schlumberger. My first boss at Exxon went to the Metallurgical division there.

BBV : What kind of research did you do there ?

AH : It was 1984-1988.

SW : Right. Schlumberger was in Richfield, CT, the lab was built and designed by a famous architect called Johnson, from Texas. One or two stories, glass, a very pretty building. You could not have your names on the doors or pictures on the walls unless they'd approve them. Schlumberger was then the Rolls-Royce of the oil field. They built very expensive analytical equipment which they put down oil wells to determine whether there was in fact any oil down there, what the rock foundations were like. They would put these probes worth millions of dollars down the well, pull them up very slowly and you would get wiggles and charts and things like that. And if they could reproduce the wiggles they would sell it. It was a very low-key company. In those days they probably made more money than all but two or three of the biggest oil companies. What they did not have was chemists, those who tried to understand what these measurements actually meant. They did have a large number of physicists and electrical engineers building the instruments. Then they decided to build up a basic rock science group, the job of which was to try to understand what was measured. And I went as head of the group, to bild up the chemistry activity with the engineers. One of the biggest electrolytes in the world is clay. It is clay in the formations that causes various forces to be formed in the earth and you can measure them.

AH : So you were not really moving to something completely new. This is the link to your previous field.

SW : Yes, but I had been doing management. At Schlumberger I was dealing with chemical engineers. But as my wife said, I was doing far too much travel. Schlumberger had labs in Texas, Connecticutt, Tokyo, Paris, and Cambridge, England. During my first year I was in the US maybe half of the time.

BBV : Is that why you stayed only four years there ?

SW : When I went there it was a booming organization run by a Frenchman (Ludeau ?). A whole book has been written about him. He died, and his chosen successor failed. There was a palace revolution. And a Scotsman was in charge, Ewan Baird (?), I think he is still in charge. At that point they were building a new chemistry facility in Richfield. They had put the foundations in, and he came in one day and said, no. Construction stopped. He ordered people back to basics. Schlumberger also had some TV stations back in France. They invested in other things. It was as if they only wanted to have Nobel Prize scientists : only the best was good enough. They did hire some outstandingly strong theoretical physicists. We looked at how oil flows through sandstone in rocks. Sprinkering (?) techniques ..very similar to how snowflakes build up on the window. Some people there did not like it : why are you doing this ? There was a reaction against basic science and people wanted to get back to building and improving equipment.

AH : Was the basic stuff modelling ?

SW : Yes, there was a strong modelling component and a measurement component. At that time we had about 30 people in this basic science group. We were told basically that we could become engineers or leave. We were given about 18 months. They were very generous. Some of the best people were in their 20s. Three of them were offered tenured professorships within a month.

AH : This is also the period of change from the mainframe to the PC.

SW : Yes, and Schlumberger was big on that. They had a Cray computer and Macintoshes. The theorists wrote their programs on the Macs and ran them on the Cray. Schlumberger also had e-mail, around the world. We were in touch with the Japanese and the French. That was really the first time that I used e-mail. They were well ahead.

AH : This must have been towards the end of your time there ?

SW : They had it from the beginning. Remember, they were well versed in how to get electronic information.

BBV : Did you go straight from Schlumberger to SUNY Binghamton ?

SW : Yes. At that time I decided that US industrial research activites had started on a down hill. Exxon had cut back on their basic research by about 50%. Seven years earlier they had doubled basically overnight. Then they had said : what would you do if we gave you twice as much money ? Give us a plan by Monday (that was on Friday). In my recollection we worked all that weekend. Within a week we had the doubled size.

AH : How would you account for the change in atmosphere, for the downturn in the mid-1980s ?

SW : A number of things : 1) oil prices had been going up but then they dropped ; 2) MBAs started getting into the business (short-termism ; now the stock price is more important than everything else) and then they looked hard at basic research. With regard to Exxon : it is a mammooth company. The corporate labs were under $50 million. When they doubled it, it got above $50 million. They rounded everything off into hundreds of millions. Anything under $50 million just did not appear in the balance sheet. 3) When the oil price went down there was no longer a sense of crisis. So you do not need any longer to investigate all the alternative forms of energy. Exxon had gone into solar, batteries, computers, a chip company. But Exxon did not really have the management expertise. At about that time Exxon sold all their battery technologies. They licensed them to a Japanese company, one American and one European. I think it was Sony in Japan. Exxon said : you mean you can not make $100 million a year on this ?

AH : It would seem that the price of oil is a really good indicator of the field of solid-state ionics ?

SW : Yes. When Exxon got out, the whole field got out. The federal government cut funding, thinking that if Exxon was not interested, then why should we be.

BBV : So how did the field continue ? Where did the incentive come from ?

SW : Europe was continuing. The Japanese had our technology. There were a few problems with it. They wanted a safe anode ; they could not use pure lithium. ... (?) John Goodenough came up with cobalt oxide. That is almost double the voltage. Sony combined that with an interpolation compound of graphite as the anode ; and came out with what is called (?). The Japanese now have some 90% of the market for all lithium rechargeables. Sony has the primary licence making sublicenses. I think the patent is running out any day now. A number of companies toyed with getting into the business. Eveready two years ago started a plant and found that they could buy the batteries cheaper in Japan than they could build them themselves. The Japanese just have such a long lead time.

AH : Your personal choice of going back to academia. There was no future in industry you said...

SW : There was no future in industry and I wanted to do my own thing. In the mid-1970s 9 out of 10 solid state chemists were in industry. About that time chemistry departments in this country suddenly realized that this is a field. We want these people. Now, 9 out of 10 are back in academia.

AH : What impact did the return of solid state chemists to academia have upon the field ?

SW : In 1987 superconductivity happened. All solid state chemist jumped on board. The result was this symposium. Meeting in New Orleans. The largest room in New Orleans was not big enough.... [too much noise]

BBV : The field suffered from the cold fusion affair ?

SW : Yes and no.... [too much noise] few people got involved in cold fusion

AH : Characterization ?

SW : Computerization has accelerated the getting of measurement results.

Most of these batteries have maybe one or two years. They last as long as the product itself. As far as environmental concerns : they are pretty darn good. [noise]

AH : Hybrid vehicles ?

SW : They are there. The Japanese have them. All that is needed is the political will to factor in the environmental advantages.

BBV : Oxide markets ?

SW : Electrochromic displays.

AH : Optimism when you started ?

SW : Optimism fuelled by end of oil. Now the end of oil is not in sight. But batteries are needed in the small electronic devices. The EV is not everything.

AH : Whom should we talk to : Frank, John Goodenough, Michel Armand.

BBV : Hagenmuller ? Steele ?

SW : Steele is still active.

AH : Fuel cell relevance ?

SW : Fuel cells are much more active in Europe than in the US.

AH : For political reasons ?

SW : No, .. [noise]

Fin de l'enregistrement

Pour citer l'entretien :

« Entretien avec Michael Stanley Whittingham », par Bernadette Bensaude-Vincent et Arne Hessenbruch, 30 octobre 2000 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article132.

—

Entretien avec Michael Stanley Wittingham, par Bernadette Bensaude-Vincent et Arne Hessenbruch, 30 octobre 2000

Lieu : SUNY Binghamton

Support : enregistrement sur cassette

Transcription : Bernadette Bensaude-Vincent et Arne Hessenbruch

Edition en ligne : Sophie Jourdin

STENSGAARD Ivan, 2001-03-08

Sophie Jourdin — 2011-11-11T21:40:34Z

Ivan Stensgaard received a PhD in physics from the University of Aarhus, Denmark, in 1977. He subsequently spent two years at Bell Labs in Murray Hill, New Jersey. From 1979 to 1998 he was Associate Professor at the Institute of Physics and Astronomy of the University of Aarhus. From then on, he has been a Research Professor at the Center for Atomic-Scale Materials Physics (CAMP).

From the 1970s onwards, Stensgaard has investigated surfaces. His primary tool before the advent of the Scanning Tunneling Microscope was ion scattering. His first publication investigated radiation damage in reactor materials, and soon he moved on to investigate other surfaces, such as platinum, tungsten, and silicon. He used both backscattering and channeling of ions to infer the reconstructions of crystal surfaces. Most of his research employed ions in the MeV range, but he has also worked with low and high energies.

Because of his extensive knowledge of surface structures and the tools used to gain knowledge about them, he was in a good position to judge the efficacy of the scanning tunneling microscope when it came upon the scene in the mid-1980s. In collaboration with Flemming Besenbacher and Erik Lægsgaard, he built up a research project (CAMP) that relies extensively upon this new tool.

In our interview, Stensgaard outlines the history of CAMP and describes some of the many uses to which the STM can be put.

IVAN STENGSAARD (IS) : In the early the days, the way I recall it at least, in the STM field, most people worked on semiconductors, where the advantage is that the corrugation revealed by the STM is generally much larger than on metal surfaces. That means that the demands on the equipment are much more modest. So it was easier to enter the field of semiconductors - and of course also the technological implications were thought to be greater in that field. But when we entered the field, which must have been around 1987, there were few groups working on metal surfaces. So although the STM was really recognized as an excellent tool, there had been some delay in really using this as a common tool in studying metal surfaces.

ARNE HESSENBRUCH (AH) : But during the period of '82-'87 you would have known about the STM ?

IS : Yes.

AH : And it was something that you perhaps watched ? You watched the development of this instrumentation and you were critical to see whether it would prove its mettle for you to begin to use it ?

IS : Yes. Well we were not, as I recall it, completely convinced that it would add a lot to the insight into metal surfaces. But as soon as we did enter the field ourselves, placed the instrument in vacuum and seen the results, we were immediately convinced. I'd say from then on it has been fantastic : it has been quite easy to achieve good results with just about any topic of investigation. One saw new phenomena almost regardless of what one studied—new and completely unanticipated phenomena.

AH : So you're saying "we" now, this is presumably the CAMP group. When did that gel ? Was that in '87 ?

IS : Yes, I do mean the CAMP group. But we began collaborating earlier. Historically, I think it was like this : I returned from the US and received this grant for building up an ion scattering facility for studying surfaces [referring to an earlier mention that is not on the tape – this part of the interview will be repeated in the near future]. Some years later, Flemming Besenbacher and I worked together on ion scattering from surfaces. We looked at small molecules, and specialized on the examination of hydrogen on metal surfaces. Then in the 80's, probably around '85 or so, we began to discuss in more detail this question of building a scanning tunneling microscope. Flemming took the initiative in those days and contacted Erik Lægsgaard. Erik was really the key person in building the STM here. And from when he started until he had a table-top version, giving atomic resolution on graphite, lasted only a few months. Of course it took longer to make an instrument fitting into a vacuum system, and so on.

AH : Did you make it locally ?

IS : Yes, everything here has always been homemade.

AH : You've never bought instruments from the outside ?

IS : No. We tend to claim here that our instrument is better than what we can buy. It may sound like boasting, but I think our results help prove the contention. The fact that we can work with extremely rudimentary vibration isolation, proves that we have an highly stable instrument.

AH : So what were the characteristics of the design – the Aarhus design ?

IS : Well, there are two basic ingredients in the construction : one is the scanner tube scanning the tip across the surfaces, and I think that was copied simply from the Binnig and Rohrer design.

AH : The empty cylinder.

IS : Yes. So, the larger problem was how to approach this scanner tube tip to the surface in a controlled way so that you would come close enough to draw a tunnel current without actually colliding. To begin with we had many ideas about some mechanical way of doing it with micrometer screws, but soon we focused upon piezoelectric materials. And I think, again, that it was Erik's idea to make an inchworm. This is a really strange story. We had a very small inchworm made : only a few millimeters in diameter - maybe 10-12 mm long. It worked well and a company called DME in Copenhagen wanted to commercialize our setup. During the discussions and negotiations with them, they found out that the inchworm principle was already known, and what was worse, it was already patented. That was a something of a setback - not for our in-house microscopes but for the efforts to commercialize it. The commercially available inchworms were much bigger and not nearly as elegant as ours. But the principle was patented, and the patent had a few years left before expiration.

AH : Oh, so the patented inchworm was not intended for the STM ?

IS : No. The patent was about 10-15 years old and had been developed for something else. Whether it was developed for one of the topografiners and what they were called, the instruments used prior to STMs, I don't know. We can check the patent.

AH : Well, the topografiner was invented at the National Bureau Standards now NIST and I don't think they would have taken a patent.

IS : We could check it.

AH : So you designed the inchworm in '87, just when you were making your first STM ?

IS : Yes.

AH : But your first STM did not have an inchworm.

IS : Yes, it was a mechanical approach.

AH : Where did you get all the information for making an STM ? Did you look at the publications of Binnig and Rohrer, did you go and see them ? Did you go to the IBM labs ?

IS : No, the way I recall it, we had no personal contact. I think everything was done just using the publications.

AH : And it wasn't particularly difficult ?

IS : Not if you had a clever man like Erik. The short time required to make the first STM also indicates that it was fairly easy. Of course in retrospect many aspects of building an STM seem easy, because we know just how piezos work and what to pay attention to. The game nowadays is really to make them as compact as possible, to make them work even with vibrations in the surroundings and so on.

AH : Yes, you were saying you had very elementary vibration damping. This is another characteristic of this design ?

IS : Yes. Exactly. When you visit other STM labs, you're frequently told that they have to work at night when there is no traffic. They have all kinds of vibration damping, entire vacuum systems hanging in rubber — springs from the ceiling or something like that. They have the microscope damped with magnetic or eddy current damping. And people had to stay quiet and not move about in the room and so on. That remained characteristic until at least ten years ago. By contrast, from the beginning we hung our microscope on three or four springs, or viton-o rings, which are really rubber springs. That's all ; we have no further vibration damping. And people can even touch the UHV chamber without interfering with the tunneling. So that has been the main characteristics of the instrument here : its ability to scan fast and under adverse conditions.

AH : Fast and robust. You have told us about the robustness, could you tell us about the speed ?

IS : Fast scanning is interesting also because it has opened up new opportunities compared to other microscopes. There are more fast-scanning microscopes today but to begin with we scanned faster than most others. We scanned at the rate of one second per image, where many others spent one minute per image. This gives you the opportunity to follow dynamic processes on surfaces by sequentially recording images and then replaying the images at a faster rate - in the form of a movie. That gives you a very vivid impression of what happens on the surface. You might object that a movie yields no new information, but it turns out to be a very good means of attracting attention to dynamic processes. Such phenomena miss easily when just examining static pictures. The eye is well-suited to spotting change, so that even when there is a lot to keep track of, say 20 to 40 entities on a surface, your eye will immediately pick it up a movement of any one entity. So this question of scanning fast and taking movies, is not just a question of presenting results in a nice way, it also gives you a better insight into what is going on.

AH : But you weren't capable of making movies off the bat in 1987 were you ? How long did you need to scan in 1987, roughly ?

IS : I don't recall it really. I think we could record images in seconds, but the problem was probably rather that saving and replaying images requires a lot of data storage, and in those days the hard disks were not very big. It was slow process simply to get an image from the hard disk onto the screen.

AH : Was your ability to scan quickly a desideratum in 1987 ?

IS : Early on we probably didn't focus on the time you spent recording. It probably didn't matter whether it was 1 or 20 seconds or so. But I see now [checking on the computer] that taking movies and things like that, must have started in the late 80's. Because we have publications at least from '91 where we have included, not movies because that wasn't possible, but results based on these techniques.

AH : And what sort of thing did you image ? Metal surfaces with adsorbed atoms ?

IS : Yes, of course the standard sample in those days (as it still is for testing an STM in air) was graphite. Of course we used that as the test that our STM was working properly. Having done that we moved rather swiftly in the surface science direction again. We examined some gold-plated plastics, simply to investigate the micro-roughness. The purpose was to test the coating of large mirrors of an x-ray telescope to be used in a satellite. We also investigated some biological samples. But we were really implementing the STM in a vacuum.

AH : You say you were immediately convinced, when you saw the images, that this was a useful tool. It was seeing the images that convinced you almost instantly ?

IS : Yes

AH : Why ? There are many problems with the imaging process of course, with the noise and the interpreting just what the tunneling current actually is referring to. On metals this is less of a problem than semiconductors. Was that a help to you ?

IS : Yes, to some extent it was. Let me just mention the first system we examined, to maybe make references to that. Once we got the microscope into a vacuum we continued our work on small molecules on a metal surface. The first system we examined was one I had investigated earlier using ion scattering. We had absorbed oxygen on a particular copper surface, a copper (110) surface. And it was known what happened to the oxygen, how the surface reconstructed. What was not known was how the process took place, and that was revealed immediately almost with the STM, because we could look upon the surface while the reconstruction took place, and we could make a movie and watch the process.

AH : That must have been exciting.

IS : Yes, and then I was at least totally convinced at that time that here was an amazing tool.

AH : So the problems that there might be with interpretation were really secondary to you, you said that even with all those problems, "it's still exactly what I need ?"

IS : Yes, you said that in the case of semiconductors it is more difficult to relate the STM-produced image to the surface corrugation. That is correct of course, but you could say that we had a similar problem on our hands with oxygen on a copper surface : were we imaging the copper or the oxygen ? And it turned out that we were usually imaging the copper. This posed the question : why not the oxygen ? And why is it sometimes just the other way around, that we image the oxygen and not the copper. So scanning on metals was not completely free of problems, at least not when you have the adsorbates on them. But if you image one clean surface with only one element present, then the interpretation is straightforward.

AH : What I'm trying to understand is that when you use a completely new tool, you cannot know whether it works.

IS : I think the problems of instrumentation were so insignificant compared to the insight gained, that we were absolutely convinced of the amazing utility of the instrument. That's the way I recall it, really. There was a trend in those days—probably through the 90's—from static to dynamic problems. Other methods, such as low-energy electron diffraction, high-energy ion scattering, x-ray diffraction, are better suited for static problems. You can induce a reaction on the surface, and then you can take your tool and find out how the surface has changed. But with the STM you had a tool with which to see the transformation from one state to the next. Later on, you could even follow single atoms moving on the surface. That was really amazing, and almost impossible with other techniques. Field ion microscopy has been able to do it in some cases.

AH : Before the STM, you were using tools like ion-scattering, but it was not the tool that defined your research. Now it looks like the STM defines the group.

IS : I don't really think that's correct. No matter what you investigate,
you have to take both things into account. You have to find an interesting problem amenable to investigation with your background, its relevance and so on. Then you have to consider the available techniques. You have to find a topic amenable to the techniques available to you. I think that also describes what we did with the STM. It is a question of resources. The microscope does not define the activities ; a natural development has rather taken place. I mentioned before that we first investigated small molecules on surfaces, and we have continued to do that. Our research has now diversified but it is still to a large extent coupled to chemical reactions and the like. We have studied surfaces in greater detail – also clean surfaces although clean surfaces are less interesting for STM research because one can get the information by other means. But when you grow metal on metal for example, what happens ? How do these atoms of one metal, influence the properties of a surface of another metal. How does the surface restructure ? And, to come back to my initial point, how do the chemical properties change ? What happens if we now adsorb oxygen, what happens if we carry out a chemical reaction, let's say oxygen and CO reacting on the surface. In all these cases there has been a connection to the initial questions.

AH : Have you expanded the number of chemical reactions you worked with ?

IS : Over the years we have worked with a number of chemical reactions, but in the last few years we have focused more on catalysis. We have for many years collaborated with Haldor Topsøe AS, one of the leading companies in the catalytic world. We have collaborated on a number of issues, in once case a new catalyst was developed on the basis of our results. We proved scientifically that the catalytic conversion works. Whether that catalyst in the end will be commercially available now depends on other considerations, such as the cost of producing a catalyst, its lifetime and so on.

AH : But you discovered new catalysts with the STM, is that what you're saying ?

IS : We discovered a system that turned out to have possibilities in catalysis. We could talk in more detail about that, but it's a story in itself.

AH : Okay. What can you do now with the STM that you couldn't do in 1990 ?

IS : There has been constant improvement in speed : the rate at which you record and replay images. And new designs have made the microscope usable under new conditions. It now works over a large range of temperatures and pressures. To begin with experiments could only be carried out at room temperature, whereas we now can work from 20K or so and up to maybe 150ºC (500K). This increase in the temperature range is important for the investigation of dynamic processes because the rate at which they proceed is governed by temperature. And if you wish to study a certain reaction or a certain diffusion property, you have to have the events happen at a rate you can follow. That means that you shouldn't have too many events per second, preferably no more than one event every few seconds. And you can normally do that by adjusting the temperature.
We can also work at many different pressures now. Early on we had to work either at atmospheric (ambient) pressure or else in a very high vacuum. We have recently become able to work in the full range of pressures from ultra high vacuum to atmospheric pressures and could in principle make the system work at even higher pressures, if it weren't for some windows unable to withstand atmospheric pressure. And that again is advantageous for catalytic research, since all catalytic processes run at high pressure and high temperature. In the surface science community there has always been arguments that their field would help improve catalysts and understand catalytic reactions. That is to some extent true, but there has also been a lingering skepticism whether the processes taking place at atmospheric pressure remain the processes governing chemical reactions while raising the pressure from 10-10 Torr to atmospheric pressure. So that has been an important result : that at least in the one case that we have done so far, the system behaves identically at high pressure and in an ultrahigh vacuum, it's exactly the same things that govern the processes.

AH : What do you have to change in the STM to make it amenable to the range of pressure and temperature ?

IS : Actually not much was changed ; it's basically the same setup. The only major change is that it is located in a minor vessel ; it's in a minor chamber with a smaller volume, which is the volume that is brought up to high pressure. The suspension system has changed also, but the basic STM is the same. The suspension system is still based on a few springs, and looks differently, but the system as such is really the same. And of course minor things like gold coating surfaces to avoid reactions of those, but the heart of the microscope is completely unchanged.

AH : Why didn't you do these things 10 years ago ?

IS : I think in the field of ultrahigh vacuum there have been so many extremely interesting topics that there simply hasn't been the capacity to look in other directions. We should bear in mind that when CAMP was established in '93, much more funding became available than before. And the group grew much bigger. And although to begin with we also focused very much on processes at low to high vacuum, then at least during the second period of CAMP (from 1998 onwards) we have been able to diversify. High pressure is simply a natural development out of our original research. When I refer to new fields, I mean investigating organic molecules and other biology-related issues. So our research program has really developed quite naturally.

AH : So you started CAMP in 1993 - you, Besenbacher and Lægsgaard.

IS : The history of CAMP is more complicated – it is related to changes in the funding of Danish research. A large insurance company, Statens Livsforsikringsanstalt, was sold and a fund, Grundforskningsfonden, was set up with the money from there : 1 or 2 billion Danish kroners. Interest from the capital there was to be spent on basic research in all fields. In those days the interest rate was high and leading to a fair amount of interest each year. They requested and received many proposals for research centers. I don't recall exactly but it was a very large number. And in the end they funded 23 centers in all kinds of science : medicine, humanities – Søren Kierkegaard. We got a center too, a collaboration between our group here at Aarhus and Jens Nørskov's group at the Danish Technical University at Lyngby. The group there focused mainly on theory, and Nørskov was the director of the center, as he still is technically. The reason the two groups joined in this project was that we had had a prior collaboration within another program called FTU, research for technological development. In addition Flemming had collaborated with Jens Nørskov on another topic. So we knew each other. A proposal was made based on the joint resources of these two groups and after some external referring procedures it was eventually funded.

AH : And the project was focused on the STM ?

IS : I think the scope was broader : the interaction between small molecules and surfaces, to some extent chemical reactions. Our tool of investigation was STM but the center as such was not a STM center, it was a center doing research in a specific field. And our tool of research was the STM.

AH : You mentioned that you had contacts with Topsøe and other companies. Have you had contact with chemists, people in chemistry departments ?

IS : We have, but not much.

AH : Are they not interested in this ?

IS : I think they are in many cases, but we work in surface physics, as it is called in Danish. The English term, "surface science", is more neutral. Of course what we do is to some extent surface chemistry. But our background is just physics. You could say that a center like this might just as well have been placed at an institute of chemistry. It just so happens that we had this collaboration, and that we had not had the opportunity to interact much with chemists.

AH : So it's not the barriers between physics and chemistry that are particularly high, it just hasn't happened ?

IS : It just hasn't happened. It might have worked out differently, had we had a common institute instead of a separate physics and chemistry institute. Some of the activities going on here might as well have been placed in the institute of chemistry and vice versa. Nowadays it's not that natural to have this division into two institutes.

AH : How far is it from here to chemistry ?

IS : It's just across the parking lot, 100 meters. We're even connected underground to them, although it takes a specific key.

AH : But you don't go to each other's seminars ?

IS : Very infrequently.

AH : This does seem surprising and in need of an explanation. No ?

IS : I think much of what we're doing is of interest to chemistry as such, but our institute is comparatively small. Chemistry and physics are amazingly broad fields and our small institute is only able to cover certain areas. It has just so happened that we work in a field without a natural counterpart in the institute of chemistry. There are no ill feelings on the other side of the parking lot ; it's not based on that.

AH : And what about chemists in general out there in the world ? Do you get resonances ? Where do you publish, for instance ?

IS : We publish in papers with as high an impact as possible. We have published very large number of Physical Review Letters during the period of CAMP, on very few occasions in Nature and Science also. But that is not that easy, and sometimes you feel it is more difficult being European than if you had been American, but that's another story. We publish of course also in other journals ; some material will go to Surface Science. Surface Science does not have that high an impact, but it is obviously a very natural journal for people working in surface science. In my opinion the quality is rather mixed, but these are the main journals that we choose. We do not publish much in European journals, or journals that are particularly European such as European Journal of Physics and European Physics Letters.

AH : For any particular reason ?

IS : Simply because impact and visibility are low.

AH : When you say that in Physical Review Letters the visibility is high, is it not limited to the physics community ? Isn't your work broader ?

IS : It's probably correct, but we have colleagues in other places working in chemistry departments. And some of them will also publish in Physical Review Letters. I think it is recognized as some natural place for good work, also. But we have also published in Chemical Physics Letters, there are also a number of publications there, but they're not quite as prestigious as Physical Review Letters.

AH : Are you under pressure to produce results of commercial interest and if so, does this conflict with your own interest in pure science ?

IS : I don't' think so. I don't think we are under much pressure in CAMP to produce results of direct relevance to industry. I do think that we in CAMP all see an extra benefit or satisfaction in producing something of relevance to the "real world” and not just to pure science.

AH : So when you get around to renewing CAMP for another five years, the grant-giving bodies will not look to commercial applications ?

IS : It won't come to that. The funding will stop after ten years. It's the general policy that centers such as ours may reapply only once, so that they run for a maximum of two periods. After two periods, they ought to find alternative funding and in some way become a more integral part of the institute. What will happen in two to two and a half years from now, I don't know.

AH : You are not worried ?

IS : Not terribly, I think some kind of funding will come. I think that the government has set aside some funding for integrating centers into their host institutions.

AH : The reason I'm asking these things, is that Jens E. T. Andersen at the DTU was telling me about tremendous pressures. The DTU has now a patent office, and renewal of academic contracts is subject to results in terms of patents rather than scientific publications.

IS : The emphasis on patents has definitely increased here also, but in my opinion it has not yet become a pressure. There is a greater emphasis on it, and some of that emphasis originates from the government. A new law was introduced in Denmark. Up until maybe a year ago, you had the rights to exploit your own inventions, even as an employee and civil servant. That has now changed so that when you develop anything patentable or otherwise exploitable, you have to first contact the university. Your invention will be assessed. The university decides whether it wants to patent your invention and exploit it. If it declines, then you are free to do it yourself. So you could say that maybe the timing is a little bit strange, because on the one hand you remove some carrots from the researcher and on the other hand you apply the stick to encourage work resulting in patents. I think the general political perspective is that a fair amount of knowledge of interest to industries is generated at the universities, but no good forum for the transferal of that knowledge exists. Maybe the thinking was that having the knowledge documented in patents would facilitate the transferal.

AH : Is it possible to pinpoint advances made in the field of catalysis over the last ten years related to the possibilities of the STM ?

IS : I think this story about developing a catalyst from scratch based on pure research is rare, almost unique. There are no more than one or two other examples. Normally catalysis has been a highly empirical field. Developments have mostly been trial and error - of course guided by different kinds of knowledge. But in the end it came down to trying something, modifying it, changing the stoichiometry or the ratios, optimizing and so on. The understanding of the catalyst emerged gradually out of this process. By contrast, ours is a clear case of going directly from scientific insight into the working of a catalyst to its development.

Fin de l'enregistrement

Transcription : Arne Hessenbruch

Pour citer l'entretien :

« Entretien avec Ivan Stensgaard », par Arne Hessenbruch, 8 mars 2001 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article131.

—

Entretien avec Ivan Stensgaard, par Arne Hessenbruch, 8 mars 2001

Lieu : CAMP Aarhus : The Scanning Tunneling Microscopy Group, Aarhus University, Denmark.

Support : enregistrement non précisé

Edition en ligne : Sophie Jourdin

WHITESIDES George, 2002-01-28

Sophie Jourdin — 2011-11-10T17:04:18Z

George Whitesides

Mallinckrodt Professor of Chemistry, Harvard University

George Whitesides' group in Harvard's Department of Chemistry and Chemical Biology works on many topics : Biomimetics, Biosurface Chemistry, Complexity / Emergence, Materials Science, MEMS, Microfluidics, Micro- / Nanofabrication, Photonics, Polyvalency, Self-Assembly, Surface Science, and Tools for Biophysics and Biology.

BERNADETTE BENSAUDE-VINCENT (BBV) : Do you see any changes that you would like to mention in your field over the past 20 years.

GEORGE WHITESIDES (GW) : 20 years ago there was not any materials science in my field, which is organic chemistry. People made polymers, but they didn't really think in terms of materials, and all of this stuff of electronics and optics and unusual functions and biocompatibility and things like that were - some of them were not even concepts and some were not considered materials science because nobody thought about materials science. Materials Science in the last 20 years has come from something that was done with airplanes to be a real part of chemistry - that is really interesting I think.

BBV : Have chemists been involved from the very beginning or did they jump on the bandwagon later ?

GW : Well, no, I guess my sense would be that chemists were involved from the very beginning in the sense that they made materials. Because after all most materials in the world are actually made by chemists.

We have metals, but ceramics often come out of chemical backgrounds, and all of polymers come out of chemistry but they were thought of as being fibers or coatings or something else and the idea of thinking about them as materials - it's a re-naming but it was helpful for the field to think about how to organize itself intellectually among other things, and then what was a little bit of a change was that at the beginning the financial support was primarily from the DoD for its own purposes which was primarily metals and ceramics for airplanes and armor and hot-sections in engines and things of this kind. It is recently that this has changed. Chemistry and chemical thinking is an increasingly important part of materials science which means there is now some money which means it is worth the effort for chemists to think about that as a community they might want to be involved in. But chemistry has gone from an area dominated by the notion of making natural products to an area in which probably the two interesting areas are bio - and most people would say this is the biggest deal in chemistry at this point - and materials. Synthesis becomes an accessory technology which enables one to make these materials that you might want for either biological applications or materials applications.

BBV : And what about the electronic applications for chemistry ? Is there any future in that ? You have been working a lot in that.

GW : I think that is going to be one of the big deals in electronics. The argument there is that there is a certain specific way of thinking about electronics which is silicon and semi-conductors and that works fine. But my prediction is that there is going to be a new class of devices that is going to be perhaps slower but much cheaper, so that the ratio of benefit to cost goes up but primarily because the denominator goes down rather than because the numerator goes up. The notion with these and with optical photonics systems and with organic LEDs is low cost, ease of fabrication, the ability to integrate a bunch of different kinds of functions in the same thing whereas if it is all polymers you don't have to worry about compatibility between the 500-degree processing step and an ion-beam step or whatever it might be. That is organic chemistry. There are two components : one is the laser and the second is the coating. Optical recording now dominates a certain segment of that industry and it is entirely because what chemistry has made possible. CDs are the same thing. These are optical CDs but the older CDs were the same thing. I think chemistry has found opportunities in thinking about the collective properties of matter as opposed to thinking of the properties of individual molecules - it is a little bit of a revelation but it opens all kinds of doors.

ARNE HESENBRUCH (AH) : Shall we try to get at the history of the last 20 years ? What in your opinion has been the most important changes in the last 20 years ? You have been in the field for that long.

GW : It is more like 20 years. I really began to think seriously about materials science when I came to Harvard. At MIT I was primarily concerned with inorganic chemistry and catalysis. So I came here and became involved, but what made a big difference from our point of view was the development of self-assembling monolayers. Self-assembling monolayers were particularly interesting - and I think actually very interesting for many chemists because they made the point that you could design molecules and thereby control macroscopic properties. You make a kind of molecule and a drop of water beads on the surface and you make another kind of molecule and a drop of water spreads on the surface. So that idea of being able to engineer macroscopic properties based on molecular-scale synthesis was a pretty interesting idea and fairly new at the time.

AH : When ?

GW : That happened ... the first identification of SAMs per se was early '80s and forget exactly when, whether it was '83 or '84, and then the real understanding that you could put them together was done by Ralph Nuzzo - he did the first identification of these as structurally ordered systems. And then we did a lot of the work that connected them with materials ; we were actually working on it at the same time and we started publishing papers in the period of 88-89. So it's really only been about a decade. Now polymers have been around for a long time and we have been working on polymer surface chemistry in the late '70s. But we didn't really call it materials, we called it polymers and it was very hard to do because you couldn't really get a grip on it. You'd start with a piece of polyethylene and we used to put in chromic acid solution and that burned the surface and introduced a bunch of carboxylic acid groups which we could use for various purposes but it was very hard to characterize these things and the surfaces were pitted as a consequence, so we never really had a good grip on the density of surface functionality, the roughness of the surface or any of those things.

AH : What did you do to characterize ?

GW : We used XPS and we developed a whole series of techniques like contact-angle titration - which is an idiot idea but the notion that you make the drop more and more basic and you see if it spreads more and that tells you if there is an ionizable group. This is the kind of thing a chemist thinks of first but not a materials scientist with a metallurgy background because they don't know that carboxylic acid groups exist. Self-assembled monolayers still are, I think, the best of all the materials systems - and this is almost independent of field : ceramic, metal or anything else. If you want something which you can control in exquisite detail it is this. If you want to understand how you go from atomic and molecular level structure to macroscopic property within the range of things that it can do, nothing beats SAMs.

AH : And you knew this in the early '80s already ?

GW : No, what you knew in the early '80s was that there were ordered structures. Strictly speaking, well before that, the electrochemical guys had known that organic silver compounds adsorbed on metal electrodes. So that was well understood and they'd been used empirically for a bunch of things having to do with adhesion so there was, as in everything in science if you look backwards you find, lots of precursor phenomena. And then Ralph Nuzzo and a guy named Dave O'Lara(?), who were at Bell Labs at that point got involved in this and I think their initial interest (I actually never asked Ralph why he got into but I think it was partially because they needed ways of doing coatings of metals and - anyway they were good spectroscopists - and Ralph looked at these structures and recognized from the infrared spectra that they were highly ordered so that the idea was that it was not just going on the surface as scrambled eggs but that it was crystalline. And then we did physical organic chemistry. We took that platform starting in the early '80s and put functional groups on the terminal positions so that after the thyols formed mono-layers, you just saw a monolayer of the terminal functional group, and the hypothesis was that this would control wetting. And it did. Then the process from there was that in the early '90s we had the idea that one might be able to make patterns with these self-assembled monolayers and we had several approaches to this - the earliest one was actually an experiment I did with my own two hands - which was to take a piece of a gold dish (gold on silicon), put on a hydrophilic thyol so that water spread on it. We took a razor blade and put some scratches on it and redipped it in a hydrophobic thyol, so one ended up with scratches about a 100 microns wide they were hydrophobic in this sea of stuff that was hydrophilic then put drops of water on it and the interesting fact was that the water would not cross the lines. Had the characterization changed by then ? By that point the characterization was in pretty good shape, the combination of reflection infra-red and XPS did a lot of it. I forgot when people first saw STM images but it was ...

AH : The Nobel Prize, DI began selling in 1989.

GW : Right, and they were hard to see at the beginning because they require the tip to be far away, so it was not the first thing that was done, but people began to see crystalline rays (?). We had done a fair amount of work in the mid-80s on transmission electron crystallography. We'd taken awfully thin gold foils and run electron beams through them and seen diffraction from the organic mono-layers I think those were the first real structural indicators other than the infra-red spectras that they were united. So anyway, we started the business of stamping. I think the first paper was 92, 93, something like that. That became the basis for micro-contact printing and then for soft lithography and that brought an entire new community into it who are now on the other side of the electronic guys who are looking for new ways of getting around diffraction limits and looking for a different economics. And it has not yet made an enormous difference in microelectronics although it may well in this next stage of all-organic electronics. But soft lithography was probably the most important thing in moving the micro-fluidics community away from silicon to polymers. Now, in the long run whether the microfluidic systems we use for genomics are based on polystyrene or PDMS or what, remains to be seen - it will be whatever is cheapest. The basic idea that you did not need silicon, and in fact didn't want silicon or glass for microfluidic systems : all you wanted was that it was cheap, transparent, and easy to work with, and that is polymers. And now you put those kinds of things together with the idea of conducting or photoactive polymers and ever-increasing resolution of these printing and stamping techniques and the economics which are just phenomenally better than traditional methods when you don't need the kind of precision that the photolithographic methods bring, and you find all of a sudden that there is a new approach to making micro- and nano-structures. It is an interesting evolution. What about the biological ? Well, the biological has also been a big deal and the issue there is interesting on a couple of levels : one of them is that biology since the 60s, which is when practical sequencing first really started, has been profoundly reductionist. The whole notion is that you get the gene sequence and everything comes from that by some unknown process. That is not true of course. People now understand that it is not clear what one does with the information of the genome : which will be useful, how you combine that with proteomics, which will be useful in cell biology, which will be useful in knock-outs, which will be useful in the ... and so on. These are all interesting questions that we don't know the answers to. Biology is pretty complicated. In developing biology, as in any field, you need new tools. And new tools are microfluidic devices for genomics, new ways of manipulating cells which have to be in fluids.

AH : Could you put some dates on those new tools ?

GW : They were done in silicon in, maybe, the 70s. The guy who did this was named Andreas Manz who is now at Imperial College in London. At that time he was at Sandor ... Ciba-Geigy ... I forget.

AH : Basel, anyway.

GW : He was in Basel - I think he was in Ciba-Geigy. Of course it was an internal project so none of it was published at that point. He had two post-docs, one named Mike Ramsay, the other named Jed Harrison who were both migrant ; Mike to Oak Ridge and Jed to Edmonton, Alberta, where they started to make microfluidic systems. And that is really where microfluidics started. Other people, Roger Howe, did have an important contribution. In fact, Andreas made some of his first systems out of PDMS - unpublished stuff - he recognized the virtues of this nice elastomeric polymer even back then. But he couldn't publish it and I think the company wasn't very interested, so it sort of languished for a period of time and then this genomics came along and there was this need to find better ways to crank out data large quantities of data. Then there was a real need for microfluidic systems that were parallel with which you could generate lots of information. That was an enthusiasm that began to build in the 80s, late 80s, and people had been making devices using silicon microfab technology and it was clear it was just too cumbersome - it took too long ; they didn't have any control over the surfaces and then we among others made the point that if you use self-assembled monolayers you could get exquisite control over the interface between the materials world and the biological world. We have done a lot of this in collaboration with a guy named Don Ingber here at the medical school. This is in the late 80s, actually the most interesting part of this began came fairly rapidly after we began contact printing or that is when you saw some really neat things. So this was, I would say, 1994 or 1993, I forget when the research was done, but in that period of time. So that was one theme in this : that you could make the inorganic materials of gold films, or whatever they were supporting, you could make them compatible with biology using self-assembled mono-layers. But at the same time other people had begun to tinker with different ways of making micro-fluidic systems. I don't know that I can say what all the threads were, but certainly one of the threads was a discovery that we made that instead of using photolithography and clean rooms and all the rest of that you could do the design, print them out on a printer at scales that were perfectly useful for this kind of work and then you could design quite sophisticated systems. Other people were designing quite sophisticated systems at the same time using conventional lithographic methods. We made a point that you could do it very easily using these soft lithographic methods and that provided quite a stimulus, not to the generation of the final systems necessarily, but to the process of invention because lots of people used those rapid prototypic methods for trying new kinds of devices. This has also been an area where the industrial groups, particularly start-ups, have had a very big influence on things. Probably the first company that was a serious effort in this was Caliper. Caliper was a Larry Box(?) special and it's doing okay as a company. It is focused now on micro-fluidic systems for high-throughput screening for the pharmaceutical industry - it was one of the first to do that. There was a fellow named Lee Hood(?) who was named Hunkerpillar(?) - I think a bioengineer - developed a series of devices for sequencing of DNA and proteins which were commercialized by a company called Applied Biosystems which was one of the early darlings of the biotechnology industry, and those were not intentionally micro-fabricated - they just turned out so because you needed lot of them and small. They ended up making nice small systems - not very small but small systems. And then there was another thread to this which was the whole notion of high-throughput screening which had a number of connections that tied together. One of them was just the need in industry to do lots and lots of experiments in parallel the acceptance of 96 ??? plate formats which was the first of these. And then the idea of parallel synthesis, combinatorial synthesis, parallel synthesis which came partly from Bruce Merrifield – he got the Nobel Prize for solid state synthesis of peptides - and partly from a bunch of people including, at least I give credit to, a man named Mario Geysen as being the first person to do combinatorial synthesis, parallel synthesis, on pins. They weren't terribly small but he had that notion. Out of that came the whole idea of very large-scale parallelism in synthesis which had a requirement for making things small which led to new requirements for small systems. It is an interesting area, the bio-area, both because it has had an important impact on genomics and drug discovery and also because it provides a bridge between these two areas of biology and materials science. This is where they come into contact.

AH : You have put together elements of techniques and ideas. I presume that funding structures have had impact on the history also ?

GW : Yes. Most of the funding for materials science in the US has come from DARPA. DARPA also got interested in the biological stuff in the mid-80s, maybe a little bit later than that. Their driving concern was with biological weapons - biological defense. The United States does not have an offensive program but it was clear that there was a potential problem there and then in the late 80s there was a Russian defector and then in the early 90s another, Ken Alabakoff(?), who spent a lot of time talking about what the Russian program had done. It was clear that the Russians had had a very very large program in biological weapons and it really bothered people. So there was a growing effort to think about how to build sensors and analytical systems, how does one put together a defensive program in this. That ended up being an important bridge between the materials community (which was the DARPA community) and the biological world. One of the things that DARPA does very well as that when it decides to go into an area to put in enough money for a sufficient period of time that it is actually worth people's effort to go and learn how to do that because they can run programs that make a difference. They get, I think, a lot of credit for building the biological component for micro-fluidics and then of course a very large fraction of soft lithography was funded by DARPA and their interest in that was largely new methods of circumventing the natural limits in photolithography for very high-density electronics. It has not in fact changed that - I mean these techniques are not used for high density electronics - but I think they are going to be the basis for low density low-cost electronics, the organic stuff. I think this whole area is one that DARPA gets the major credit for. Had DARPA not put the money in it would not have happened or it wouldn't have happened the way that it has. NIH has been very resistant to doing anything in this because NIH only does science, it doesn't develop tools. I think it is an enormous strategic mistake on their part but they have basically been parasitic on activities funded by other parts of the government or funded in industry, in start-ups, for the tools that they use and the biological community uses. Then of course there has been some work in the NSF and DoE but not big programs.

BBV : So do you see the contribution of your group as providing new tools for materials science ?

GW : The biggest contribution is to make the connection between physical organic chemistry and materials science - that is the idea that you can design molecules, or design matter by synthesis at the molecular level, and thereby influence macroscopic materials properties. The second is to put together a series of tools, particularly self-assembled monolayers and soft lithography and illustrations of the uses of these in microfluidics and particularly in bio which have caught people's attention. This is an interesting strategic decision : we decided at the very beginning that we were going to proselytize for the area, so we made a really big effort to have anyone who was interested. We invited them to the lab and tried to teach them everything that we knew. It is one of those interesting philosophical issues in science : when you have something that is new and interesting you either try to hold it close or you try to spread it as widely as possible, and we really made a big effort to spread it because I thought it was going to be very useful. Quite a large number of people would come for two-three days or a week over the course of time and then these people have gone out and started programs and then of course the graduate students come and learn how to do these things and they go off and start programs. So, the dissemination has been quite rapid, primarily because it is very easy to do. That is another philosophical issue : I like to do research that is really easy to do because other people can do it. If you want to have an impact on the community at large it is easier if you keep the bar low to people getting into the area rather than making the bar high. So, minimal capital investment.

BBV : And how much time do students need when they come to be trained in the techniques of self-assembly ?

GW : Two days.

BBV : Two days ? It is kitchen experiment !

GW : It is kitchen experiment. You take some wafer and you dip it and you pull down the stamp(?). That is not complicated. And stamping is literally no more difficult than putting a rubber solution on a rubber stamp and putting it down by hand and pulling it off and it's done. It obviously gets to be more complicated than that but you've got the basics at that point. There is a little issue there, which is : you say this is trivial, and in a sense it is trivial, but it is trivial because some very smart students spent a lot of time understanding these systems and figuring out which ones worked so well that they could not be made to fail. That is the criterion. The simplicity at the end is the result of a lot of hard thought along the way not just by us but by the whole group of people who was interested in self-assembly and related areas. The second thing is the tools and the third is the notion of self-assembly. Generally, organic chemistry has been largely concerned with making molecules by putting together covalent bonds and self-assembly is how you make materials through non-covalent interactions. So it is a switch in emphasis. We are certainly not the only ones who've worked on self-assembly but we have probably been more emphatic in making the case that it is a technique that can be used in materials science than other people who have been concerned with making structures in solution or how proteins fold or other things of that kind.

BBV : It is striking that other groups doing self-assembly have had biomimetic inspiration whereas in your group it was not a leading ...

GW : Well, we do biomimetic stuff. If you talk to some of the people around, Mila Boncheva, who I think with a little luck you will meet, has made this wonderful device. You basically have a string of something and you put this in suspension, it folds up and one part of it becomes a high-frequency ring oscillator and the other part becomes a shift register. It's quite intentionally patterned on the idea of protein folding so it is biomimetic in that sense. But the major issue is the generic problem, which is to understand molecular recognition in biology because if you want a single process in biology that is important it is the recognition of a ligand by an enzyme-active site, or whatever - that is the reductionist end of the working part of biology. There has been lots of work on that - and then self-assembly came in, as a result of two things : one was to try to model biological recognition and interestingly this has never really worked. There is an enormous amount of molecular recognition that has gone on in methylene chloride solution, but of course water doesn't go on in methylene chloride, so in organic solvents a lot of good work has gone on which has led to systems that are pretty efficient in molecular recognition. But noone has come really close to duplicating the efficiency of biological molecular recognition in water because we have to learn how to handle the hydrophobic effect and we don't know how to do that yet. So that is one theme. The second theme was the stuff that Jean-Marie Lehn, Cram, and Pedersen from DuPont got the Nobel Prize for, which was just understanding the crown ethers of the right size would wrap themselves around a sodium ion. That was not really molecular recognition, but it was self-assembly ... well ... Jean-Marie calls this supermolecular chemistry, so it is chemistry beyond molecules. It was an important first step in making the case that it isn't just making covalent bonds that's important but these events in which things recognize one another and get together without making covalent bonds are also important. So these two things came together in self-assembly. One virtue of this place is that students are very good and very independent, and the groups are big so that we can have biologists, chemical engineers, physicists, organic synthetic chemists, and materials scientists. That makes it much easier to think about putting biology and materials science together, or organic synthesis and microelectronics ; you know x and y, where x and y come from very different directions. It is a lot harder to do that in smaller groups.

AH : Do you think there is any purpose in doing history of science ?

GW : Oh yes. Understanding what this funny activity is of creation. Hang on, I'll be right back - this last question is important ...

History of science. If you look at history of science you can see where interesting things came from. Now, the question is, can one learn something from the activity, and I think the answer is yes. The question that comes up in this area is, is it sufficient just to put different research areas together in order for good things to happen, or do you have to have a brilliant conception ? No, I don't think in this case one needed a brilliant conception. It was putting things together - with some luck - self-assembled monolayers were an experimental observation, they were not a theoretical prediction confirmed by experiment. It still amazes me that soft lithography works as well as it did. In any event, one can ask where ideas came from, and from that point of view the history of science is an enormous contribution. The question which is never clear is, to what extent are there lessons that you can learn from one success or one failure that you can carry over into other areas ; and in particular : what is the mechanism by which whatever lessons you learn are transmitted to the people who are the ones who in principle would benefit most, who are the people just beginning their careers, but who are in general the least interested in listening because they are eager to get on with it. They have their own usually not very well-formed theories as to how to do things and it is based more on their own particular instinct. A lot of their instinct, in fact, turns out to be replication of the experience in graduate school. That is probably the least perceptible but longest lasting lesson of the graduate career, because people tend to do their research the way they learnt to do research which was the way their research director did research. That stylistic issue comes across. In a sense, one of the great sadnesses of science is to look at people at the age of 50 and realize they have spent their entire career working on their theses with minor variations on themes. It is not a happy outcome. What they learnt was, don't step too far out of this particular circle ; just sit there and fret away with this stuff. So, I think there is enormous opportunity for the history of science to be useful, and even predictive if one could figure out what to do with the information. As we made a big effort to teach people how to use soft lithography, I think all scientific enterprises, particularly with fields that move rapidly, which is what science does : it is always looking forward and almost never backward, one needs some clever way of figuring out what the short-form lessons are from what you do, what you have learnt. But I don't think the user will study things. A book which I think is a very interesting example of history of technology which has made a big difference is The Innovator's Dilemma. Have you read The Innovator's Dilemma ?

AH : I haven't read it.

GW : You should read The Innovator's Dilemma. It is by a guy named Christensen, who is somewhere here at Harvard or MIT. It's history - history meaning business school history, but it's close enough - and the question is : look around and you find big technology changes, and how do companies react to that ? And the answer is in general : incredibly badly. And this book has really caused people to think about how they run their technology programs (in companies) because the failures are so stark that as a big company person it really does not give you a lot of confidence that whatever you are doing is going to survive. One of the lessons in this is this : the mantra in the United States is listen to the voice of the customer ; the customer will tell you what you do. And one of Christiansen's lessons, loosely re-phrased is that if the field is technologically changing the thing that will kill you is to listen to the voice of the customer, because the customer never wants change - the customer has people trained in some technique, they've got capital investment and so on and so forth : the last thing in the world they want is change. So you listen to your very conservative customer and some little company who wants to take your customer away or create new customers, is going to zip around on the side. Now the interesting issue for you all is, you are doing all this stuff and my guess is that websites may be interesting for other historians of science but I don't think it will make any difference to scientists. So what you need is a nice short book which summarizes all of this in terms of lessons. What are the lessons that you can draw from this ? What has succeeded in what circumstances and why ? And what are the risks, and what has failed ? People hate failing. So look around and what are the failures, and what did they not do that prevented them from competing effectively ? I think if you think about history of science rather as the business school thinks about its analyses in terms of something that's branded in terms of suggestions for the next generation or the current generation of operators rather than sort of a passive observation it might have more impact. I don't know whether you care whether it has more impact or not.

BBV : We care about our impact.

AH : I care a lot.

BBV : Thank you very much !

Fin de l'enregistrement

Pour citer l'entretien :

« Entretien avec George Whitesides », par Bernadette Bensaude-Vincent et Arne Hessenbruch, 28 janvier 2002 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article130.
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Entretien avec George Whiteside, par Bernadette Bensaude-Vincent et Arne Hessenbruch, 28 janvier 2002 : on history of organic chemistry and materials research and on the purpose of history of science.

Lieu : Prof. Whitesides' office at Harvard University

Support : enregistrement sur cassette

Transcription : Bernadette Bensaude-Vincent et Arne Heseenbruch

Edition en ligne : Sophie Jourdin

WHELAN Michael, 2002-12-12

Sophie Jourdin — 2011-11-10T15:51:51Z

Professor Michael Whelan.

BERNADETTE BENSAUDE-VINCENT (BBV) : Could you tell a few details about your own work on the experimental discovery of dislocations in 1956 ?

MICHAEL WHELAN (MW) : In the 1930s there was no experimental evidence for dislocations but theoretical predictions were built up about the way dislocations behave. What was really missing was any direct observations of dislocations, although slip lines on the surface of metals had been observed by optical microscopy. The question was how could that occurat the sort of stresses that were observed experimentally ? If you work out the stress required to push one layer over another as a whole, it is much higher than it would be if you introduce the concept of a dislocation. A dislocation is like a wrinkle in a carpet ; Peter Hirsch used this image. When the concept of a dislocation came to the forefront with many papers about the behaviour of dislocations, there were unbelievers, among the Russians in particular. At the Cavendish Laboratory in Cambridge in the group of W.L. Bragg they had suggested simple X-ray experiments to detect the small subgrains that were hypothetically formed in the plastic deformation of metals.

BBV : When did you start ?

MW : I started in 1954 with Peter Hirsch. He was a post-doc in Cambridge. He had got his PhD about 1950 using X-rays to study the textures of metals. They had developed a microbeam X-ray technique under the supervision of Professor W.L. Bragg and Dr W.H. Taylor. It was essentially based on X-ray equipment - a high intensity X-ray generator with a rotating anode produced a beam of about 10 microns diameter for taking back-reflections photographs from a small area of a deformed metal.

BBV : So in 1954 X-ray diffraction was still the dominant technique for studying dislocations

MW : When I started the X-ray machine was still in the lab and there was another student still using it, Chris Ball, who eventually emigrated to Australia, and I started in the same room as the microbeam X-ray machine. I remember him telling me - you don't have to worry about the scattered beams…. I tolerated it for about six months and then moved to another room. The work with X-rays had its limitations - you could not get a smallenough beam to examine certain metals, notably nickel and copper. The scattering is very weak with X-rays and typical exposures were about 24 hours. Anthony Kelly had the idea of going to one of the new electron microscopes that had been developed to do transmission electron diffraction. An electron diffraction pattern exposure time was only a few seconds. I was asked to investigate this electron microscope technique further. Some people had already worked on it. Heidenreich in particular at the Bell Telephone Labs in the USA, but not with the idea of actually seeing dislocations.

BBV : Did Heidenreich produce the first images of dislocations ?

MW : If you read my article you will see that Japanese had also produced dislocation images. The Japanese were interested primarily inmoire fringes, but if you look at some of the pictures thatProfessor Hibi took of mica and graphite, you can see that they contained dislocation images. But they didn't really understand the concept of a dislocation. I heard that from an eminent Japanese scientist, Professor R. Uyeda. We came from the X-ray side. We were interested in crystallography whereas many electron microscopists did not know much about diffraction. It was important to have a team which was expert in diffraction to move into this field.

BBV : You mean for interpreting images ?

MW : Yes, the theory that you need to understand how the electrons interact in a crystal which contains dislocations is essentially diffraction theory. It is more or less the same theory that you have for X-rays except in the difference of scale. The theory was well known to crystallographers. It had been developed in this country by Darwin and Bragg andby Ewald and von Laue in Germany.

BBV : Where did electron microscopy come from ?

MW : Electron microcopy was developed in the 1930s by the team of E. Ruska, M. Knoll and B. von Borries working in Berlin, and was initially used by metallurgists mainly to look at surfaces. Their interest initially was to extend what they did with the optical microscope, namely to examine surfaces. They made thin replicas of surface structure and examined them in the electron microscope. They had to shadow the replicas with heavy metals to obtain good contrast. This was the main area that metallurgists were engaged in during the late 1940s when electron microscopy started to be used again after World War II, with the exception of Heidenreich in the USA and Raimond Castaing in France, who developed microprobe analysis techniques.

BBV : Did you know Castaing and interact with him ?

MW : Yes, I wrote to him as a research student and sent him some of my electron micrographs. I met him first at a conference in Madrid in 1956 at the end of my second year of research. I remember him taking me for a ride in his car through Madrid. He was a scary driver. There was a session at an EMSA conference in Portland Oregon in 1999 that was devoted to the memory of Castaing.

BBV : Did you take your Ph D in physics or in crystallography ?

MW : In the physics department in Cambridge, known as the Cavendish Laboratory.

BBV : Did you consider yourself as a physicist or as a crystallographer ?

MW : A bit of both actually. I was interested in crystallography but Cambridge had traditionally a broad natural sciences undergraduate course. You studied for three years. In the first and second years you had to study a number of subjects, for example in my case physics, mathematics, chemistry and crystallography. In the third year I specialized in physics, but in the crystallography course during the first two years I got interested in X-ray diffraction. Therefore, when I started in the Cavendish Laboratory I decided that I would join the group working on X-ray diffraction.

BBV : When did you shift from X-ray to electron microscopy ?

MW : When I started. As I have said, Kelly had initiated the work, but he left the Cavendish to work in the USA. He had taken some transmission electron micrographs with Peter Hirsch and Jim Menter, who worked in the Laboratory of Physics and Chemistry of Rubbing Solids, a subdepartment of the Physical Chemistry Department at Cambridge. He had an electron microscope with which you could do selected area electron diffraction. Selected area diffraction was a relatively new technique at that time. It enabled you not only to take an image of the specimen, but also to insert an aperture into the microscope column, selecting an area down to about a micron or half a micron in size to obtain a transmission electron diffraction pattern. You had to have a thin specimen, about 1000 Angströms thick. The simplest thin specimen you could easily obtain at that time was beaten gold foil. It could be beaten down to about 1000 Angströms thickness. It would transmit electrons at that thickness but it was heavily deformed. They saw things in the images that they could not interpret. Peter Hirsch had the idea that they could be stacking faults on inclined planes. If you can see a stacking fault it ought be possible, he thought, to see a dislocation because the dislocation in a face centric cubic metal can dissociate in two partial dislocations, like a little ribbon with the space in between them being a stacking fault. So if you could see the fault you might be able to see the dislocation by virtue of the ribbon. That was the initial suggestion that Peter Hirsch made. It was simply a hunch. Experiments had to be carried out and interpreted. That was my job.

BBV : What kind of microscope did you use in 1954 ? Was it easy to get electron microscopes in research laboratories ?

MW : At that time the Cavendish Laboratory had two electron microscopes in the Electron Microscope group headed by Dr V.E. Cosslett. One was a pre-war instrument manufactured by the Siemens Company of Berlin in 1938. You could not do electron diffraction with it. It had been picked up in Germany by the British Army as a war reparation. Ernst Ruska developed the first electron microscopes in the early 1930s based on work done in the 1920s. The first commercial firm to produce a microscope was Siemens, who engineered a microscope that Ruska had basically designed. It was a two-stage magnification instrument with a single condenser lens. You could not do selected area electron diffraction with it. You need three stages of magnification for that.

I took some electron micrographs using this instrument. The resolution was not good, but some of the micrographs of beaten aluminium showed images of dislocations. This was not realised at the time. It was only much later, with hindsight, when the micrographs were re-examined, that dislocation images were recognised.

In early 1956 I was able to use the new Siemens Elmiskop in Dr Cosslett's group. This had much better resolution, and dislocation images were recognised in the summer of 1956.

BBV : What do we see on these pictures ? Picture 1 plate 404 and Picture 2 plate 1833.

MW : Plate 404 : This relatively low magnification micrograph shows the subgrain structure of beaten aluminium foil. Subgrain boundary walls are visible. These are made up of dislocation arrays. The subgrains are about 1μm in size. Inside the subgrains there are many extinction contours. These arise from dynamical electron diffraction effects due to buckling and thickness variations in the foil.

Plate 1833 : Here at higher magnification we see subgrains of size 1 or 2 μm in diameter. In the centre we see a cross-grid network of screw dislocations constituting a low angle twist boundary, on or close to the (100) crystallographic plane. In the next subgrain we see a slip trace (the contrast feature with a 90o bend). A dislocation has moved across the grain, first on one 111 plane and has then cross-slipped to another 111 plane, leaving behind the trace of its path. In imaging dislocations by so-called « diffraction contrast », we do not attempt to resolve the atomic arrangement. There is a strain caused by the displacement of atoms near a dislocation, and it is the region of strain that is made visible as a dark line by diffraction contrast.

Only one beam is used to form the image - here the directly transmitted beam. Other diffracted beams are removed by an aperture in the objective lens of the microscope. The dislocation images reflect the fact that electrons are scattered outside this aperture. This is diffraction contrast.

BBV : What does it tell you about the material ?

MW : You don't aim at resolving the atomic structure. Metal physicists think in terms of a sort of quasi-particle. They are not usually interested in details about the atomic positions. They are interested in the concept of a dislocation as a line defect with properties such as energy, line tension, inter-line forces. What you want to see is a line.

BBV : How can you sort out the line defects that are dislocations from other spots or lines ?

MW : With some experience you can easily identify dislocation lines. Other contrast features arise from artefacts. The instrumental resolution required to observe dislocation lines is not high.

It is of the order of 100 Angströms. To see atoms you need a resolution of about 1 or 2 Angströms. Modern instruments have this resolution. To image the crystal lattice, you need to include more than the directly transmitted beam. You include a number of diffracted beams and resynthesize the atomic image by using several beams. You can use modern electron microscopes to actually see the atomic arrangement with a very thin specimen. You can gain a sort of projection of the atomic lattice structure. But then again, you have an interpretation problem. The question remains - what does the image mean ?

BBV : On which metal did you first observe dislocations ?

MW : We first observed dislocations in aluminium foil.

BBV : Following your first observation and publications I guess that there was a great excitement among physicists that increased the demand for commercial microscopes

MW : In post-war years, the Siemens company improved on the design of their pre-war instrument and manufactured the Elmiskop 1. It was presented at the London International Electron Microscope Conference in the summer of 1954. The first to be delivered from the factory was acquired by the Electron Microscope Group at the Cavendish with a grant from Nuffield foundation. It was designed mainly for biologists. Although you could do selected area diffraction with it, there was an inconvenient system for energizing the lenses which made it difficult to obtain electron diffraction patterns initially. But after a few years Siemens modified the electronics to enable fine focus illumination to be used with electron diffraction. For many years the Siemens Elmiskop had most of the world market.

BBV : Was it difficult to operate the early electron microscopes ?

MW : Most of the difficulties in those days was preparing thin enough specimens. Also adjustment of the electron beam was done mechanically, requiring some agility of the operator. Nowadays adjustments are made by magnetic deflection. Practically the only thing which is still mechanical in modern instruments is the actual movement of the specimen stage.

BBV : How long did you take to familiarize yourself with the electron microscope technique ?

MW : There was an assistant in the Electron Microscope group Bob Horne who was in charge of the Elmiskop instrument. I seem to remember that he had never studied for an undergraduate degree but he had been an electronic assistant during World War 11. He told me that he had been involved in recording ground-to-air voice communications during bombing raids on Germany using wire recordes borrowed from the BBC. The recorded voices were broadcast again during later raids to confuse the enemys defence fighter aircraft ! He acquired skills in electronics during the war. We collaborated and the first papers were co-authored by Hirsch, Horne, and myself. Horne took the pictures. He operated the instrument. The difficulty for me was to get my own hands on the instrument. But there were three viewing windows on Siemens Elmiskop. The operators window and two side windows, so it was possible for me to observe through a side window. Later when we first saw dislocations, Peter Hirsch would be observing at the other side window. To record the movement of dislocations we attached an external ciné camera, recording through the front window. We needed not only an operator but also somebody trying to tilt the specimen to give it best contrast and somebody to operate the ciné camera. So three of us, Hirsch, Horne and myself worked altogether. Another difficulty was the availability of the machine. It was the only microscope in the university. I had an afternoon session per fortnight. During the rest of the time the instrument was mainly used by biologists. (Lord Victor Rothschild was one of them. He was an eminent biologist and was Chairman of the Agricultural Research Council. He was one of the few members of the Rothschild family who did not go into the family banking business. He stayed in Cambridge doing research, and later directed research at Shell laboratories and became an advisor to Margaret Thatchers government). But when we started obtaining exciting results we got more time on the instrument. Ultimately around 1957 we got our own instrument. And we had 2 or 3 of those instruments before we left Cambridge to come here.

BBV : So it was a rapid increase. How expensive were these instruments ?

MW : In those days you could buy one for about £8000. I remember Professor Nevil Mott coming - he was the head of our department - and looking at the first Elmiskop we obtained and he said - « ah, two houses ! ». In the 1950s you could buy a professoriel style house in Cambridge for about £4000. Money was obtained from various sources. Part of the money came from the Royal Society and the rest came from the Department of Scientific and Industrial Research. The instrument was for our groups use, but it was situated as an attachment to Dr Cossletts group ; so that his technicians could advise us.

Initially we had a beam of 100 microns diameter which is quite large. The images were of poor quality, but they were not much better than Heidenreichs images because he too had not used a double condenser lens. The initial emphasis was to look at electron diffraction patterns. So we had to use the single condenser illumination. One day Bob Horne switched the lens arrangement to the system that biologists, used but with which you could not do electron diffraction. We noticed that the images obtained very clear and picturesque. After a while we saw changes taking place in the image, and the dislocations started moving around. I called Peter Hirsch to come and have a look. He said we must get a ciné camera to record the dislocation motion. One of our assistants who had worked at the National Physical Laboratory and knew something about movie cameras, advised us on who to contact at the NPL to borrow a ciné camera. We mounted the camera on the microscope, put some high speed film in it and we made a ciné film of the motion of the dislocations. We produced a silent movie. Peter Hirsch and I presented the film at various conferences and we received requests from people who wanted to obtain a copy of it for teaching students. So we started a business in the Cavendish to sell it at cost price. We still have the negatives. Recently we put it on video. I showed this movie in Japan recently on a trip to raise funds for my college at Oxford. A generation of students has grown up, who have never seen this old movie. So it is entering a second life !

BBV : How many instruments did you get when you moved in Oxford in 1966 ?

MW : We bought a new Elmiskop. With the help of research students we had converted an instrument in Cambridge to study the energy losses of the electrons when they are transmitted through the specimen. We moved it to Oxford. Then with the help of another competent research student we built another instrument based on a design of Castaing which enabled energy filtered images to be taken. There was an old EM6 electron microscope already here in John Martins lab. But we were in a Department annexe on the ground level of another building.

BBV : Did you need a special environment for using those electron microscopes ?

MW : It was not a bad building. Because it was on the ground floor vibrations were minimized. Later we bought instruments with higher resolution that required special foundations, we had concrete blocks put on the floor to minimize any vibrations coming from traffic outside the building.

BBV : How did you teach electron microscopy ?

MW : I started giving a graduate level course on the dynamical theory of scattering to research students. At the undergraduate level initially there was not much teaching of electron microscopy. There was only brief mention of it, with no experimental work. That has now changed. Undergraduates can have practical classes in electron microscopy.

BBV : Do you remember when these practical classes started ?

MW : I don't remember exactly. Probably in the late 1970s. I used to give a course on optical and electron microscopy to undergraduates. But there was no practical work ; in the practical classes they could only take X-ray pictures. Now in the practical classes they use various electron microscopes, both scanning and transmission. Compare this with the days when we started with an instrument available one afternoon a fortnight.

BBV : What is the importance of electron microscopy now in this department ?

MW : It is used as a routine technique now in the department. Anyone working in any area of materials science can get advice from the electron microscope group.

BBV : Is it also the case for the Scanning Tunnelling Microscope ?

MW : That is a different technique, a surface technique. What is interesting is that they awarded the Nobel prize to Binnig and Rohrer for inventing the STM, and at the same time they awarded it to Ernst Ruska, the German scientist who developed the electron microscope in the early 1930s, almost 60 years before. There were in fact three people involved in this work in Germany, but the other two were already dead by the time the Nobel Prize was so belatedly awarded for the invention of the electron microscope.

BBV : What is your view of Materials Science ?

MW : It is a miscellany of problems all related to the way atoms behave collectively in the solid state and even to some extent in the liquid state.

Fin de l'enregistrement

Pour citer l'entretien :

« Entretien avec Michael Whelan », par Bernadette Bensaude-Vincent, 12 décembre 2002 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article129.

—

Entretien avec Michael Whelan, par Bernadette Bensaude-Vincent, 12 décembre 2002

Lieu : Oxford Materials Department.

Support : enregistrement non précisé

Edition en ligne : Sophie Jourdin

JORGENSEN Jans Friis, 2001-03-06

Sophie Jourdin — 2011-11-03T14:01:46Z

Jan Friis Jørgensen is the main developer of the Scanning Probe Image Processor or SPIP™, a computer program that processes the output from scanning probe microscopes. This program is currently the only one of its kind in the world, and sales figures are rising steeply. SPIP™ includes the visualization of image files and various other features such as auto-correlation and Fourier transforms. Add-on modules include calibration and roughness analysis.
An electrical engineer with an industrial PhD in scanning probe microscopy, Friis Jørgensen participated in the early developments of the scanning tunneling microscope in Denmark. Erik Lægsgaard built the first one in 1987 in collaboration with colleagues at the University of Aarhus (Flemming Besenbacher and Ivan Steensgaard). Towards the end of 1987, Danish Micro Engineering (DME) turned to the production of SPMs. Friis Jørgensen joined that company between 1989 and 1990. He then worked on an industrial PhD at IBM Denmark, and also spent 4 months at IBM Zurich. From 1993 to 1998 he worked at the Danish Institute of Fundamental Metrology (DFM), interrupted by a year at the National Institute of Science and Technology , just outside Washington, DC. In 1998 he founded a company called Image Metrology to market the program, honed on his experience in the previous decade. The company is located on the campus of the Danish Technical University, in the same building as DFM. In May 2001, the company acquired an additional location close by.
Since 1999, the company has participated in the European Network on the Calibration of Scanning Probe Microscopes, sponsored by the EU Commission. The purpose of this network is to establish a basis for the application of SPMs to metrology on the nanoscale.

ARNE HESSENBRUCH (AH) : Did you study physics ?

Jan Friis JORGENSEN (JFJ) : No, not at all, I am not a physicist. Many people think that I am, but actually I was educated in electrical engineering, got a master degree with a special within biomedical engineering. And I think I've worked around seven years within different fields of medical engineering, oral visuality and also all the sound diagnostics that we've took care. When I started in a small Danish company called DME, which is still existing, and producing STM, SPM, microscopes.

AH : When was this ?

JFJ : I think it was back in 89. I worked there for almost two years and in the beginning I was not meant to work on the STM, but they were behind schedule, so I was assigned to the project and I got stuck. I stayed there for almost two years.

AH : And you had never heard the STM before joining the company ?

JFJ : Not really.

AH : After joining and learning about the STM, what did it mean to you ? Was it an exciting instrument ?

JFJ : Sure, very exciting, it was new. It was very new that people could visualize atoms, achieve atomic resolution, so it was of course attractive to work with. But as a software engineer, you are a little bit of an outsider because all the good people were physicists. It was physicists who had invented the microscope ; nevertheless I recognised several problems in the microscope : even with very fine resolution there was much distortion in the images. Already at that time many people had tried to correct it - of course in hardware which is also the best way to do it if you can - but there are still many problems that could not be solved this way. So I thought why not ? But there was no time for such work in that company, there was not enough resources, and there were many other things to do. I got a chance to work on it only upon leaving the company in November 1990, when I started on an industrial Ph.D being hired by IBM Denmark and collaborating with the Danish Institute of Fundamental Metrology and the Danish Technical University, the Image Processing Department. I finished in 1993. I could almost define the project as I wanted. I had already had seven years of experience working in private companies. But now I had to study again, and of course that was hard but it was also good to know about all the problems which I wanted to solve. It was a kind of a niche, because, as I have said before, most people at that time were physicist working on it, and so they had different approaches for solving the problems, and I used my small capabilities to solve that.

AH : Could you elaborate on the problems ? The tip and sample overlap, is that the kind distortion we are talking about ?

JFJ : Well, that was the one distortion people had been very focused on : how well the tunneling process worked when scanning over the atoms and several people produced very good theories on how to understand these mechanisms, but when you were scanning over a hundred nanometers or more it didn't really matter. There were other sources of error in the equipment itself : the hysteresis of the scanner and of different kinds of noise in the operations. These were actually the main problems and I guess within science it was given too little attention. Of course it was more exciting to look at atoms.

AH : Was it a case of low and high status research ?

JFJ : I don't know, it might have been. Anyway I think I found a niche ; I solved some hysteresis problems in new ways that nobody had considered before. And it is a part of our living today.

AH : Are there more distortions ?

JFJ : You mentioned the tip-sample which is of course a problem. It is understandable that to measure something very small, the probe should be at least as small to get a good image.

AH : That's not an issue you can address with your tools, is it ?

JFJ : I can not address it today. At that time, when I made my Ph.D, I addressed the problem but I did not solve it, because I didn't have the time for it, but other people solved it in meanwhile - I mean as best as you can. With software you can do a little, but you can't make everything perfect. Nonetheless software helps you a lot. First of all, you need an understanding of the shape of the tip. Some tips are simply too poor to use for imaging but others are acceptable. With these I can use software for correction and reconstruction, and this can lead to more accurate measurements.

AH : Were you alone in your field ?

JFJ : There have been more papers on tip characterization and on understanding the tunnelling mechanism, while there have been few on hysteresis.

AH : But in your niche were you completely alone, or were there other people working on it, say around 1990, when you were doing your Ph.D.?

JFJ : There were a few working on metrology, but not with these automated image processing tools. I think at that time it was quite unique. There was nothing out there to copy, so I had to invent the tools myself.

AH : How did the opportunity to do an industrial Ph.D. come about ?

JFJ : There was an ad in Ingeniøren, a Danish periodical for engineers.

AH : Whose advert ?

JFJ : IBM Denmark and the Danish Institute of Fundamental Metrology.

AH : Was Kim Carneiro behind this ?

JFJ : Yes. I found it natural to also connect the Technical University to the project. So I ended up with three partners.

AH : The Ph.D topic was to write software to deal with the distortions in the machine itself, the noise coming from within ?

JFJ : Yes. Maybe there was also another approach, because there had been people before doing some software by making certain algorithms and demonstrating that it could work from the very beginning. I tried to enable others to use this and I built the house bigger and bigger. It's the still the same building but we have taken it from Unix to normal PCs to really reach many people. I also stayed also a couple of months at IBM in Rueschlikon where the STM and AFM was invented.

AH : When did you go there ?

JFJ : It must have been 91 or 92 - I don't remember exactly.

AH : Were they interested in your project ?

JFJ : Sure, sure.

AH : Did they also recognize it as a niche ?

JFJ : Yes, but there was also skepticism. Some said : "well, people have been making software before, but when they leave the software gets lost because nobody knows how to use it and continue to work on it."

AH : This is a general problem of software, right ? That it has to be made user friendily and to become independent of its maker.

JFJ : Yes. It's hard to get enough attention within a scientific institute I think, because their focus is on something else ; there are barriers. At the beginning only physicists worked with the STM and nanotechnology. Now there are physicists, chemists, biochemists, biologists - a lot of people who previously did not communicate. They need to learn from each other now. And you can not build an STM without using a lot of different sciences. One of which is of course software. But at that time, people were happy simply to see an image on the screen after pushing a few buttons.

AH : So the demand for your software has developed with the increasing expectations of what you could do with a STM ?

JFJ : Maybe, I think at the time nobody believed you could start a company based on image processing for scanning probe microscopy.

AH : Because the market for SPM was very small ?

JFJ : Very small, but when I finished in 93 I considered commercializing and I discussed it. Nobody believed in it.

AH : Now it is feasible to run this as a business because the market is large enough ?

JFJ : SPM is of course a niche but from a software engineer's point of view it's simply image processing. There's no shortage of images requiring treatment such as scanning electron microscope images and optical microscope images. We now have enough expertise to address the other markets too, so we kind of expand from the nanometer range of SPM to many other things around us.

AH : I would've expected the noise and distortion in other instruments to have been completely different so that you would not be able to draw on your expertise with SPMs.

JFJ : Many of our tools can be applied to other images. Some distortions are indeed peculiar to SPM images, but there are also some generalities. For instance, satellite images are scanned line by line the same way an STM image is, and this line by line scanning can give the same kind of distortions and artifacts in each type of image.

AH : I see ; that is indeed very general. As a physics student I scanned photographs of the solar surface using an optical photometer and of course it scanned in just this way. Interesting ! When you started your Ph.D., did you already think in terms of such generality ?

JFJ : Sure ! You have to. I mean I didn't go into the field to just to be an SPM person. I wanted to learn something which I could use widely. Of course the SPM is interesting in itself, but image processing is also interesting in itself.

AH : All right ; in 1993 you finished your Ph.D. What were your options then ? Could you have gone to IBM ?

JFJ : Probably yes ; I didn't really try. I didn't because I really wanted to stay in the field of STM. I think there was still a lot of work to do so I continued at DFM.

AH : What about the big STM companies like Digital Instruments and Park, could you have gone to them, were they interested ?

JFJ : At that time, I didn't have much contact with them, and they do not pay much attention to single individuals. You really have to scream loudly to get their attention. Of course they know me now ; I have visiting several such companies. I visited Digital Instruments back in the autumn of 99, and I gave my talk twice. The second one was in an R&D meeting and that brought me a lot of attention. There is potential for some cooperation with them. Actually we have a non-disclosure agreement with them to solve their instruments' hysteresis problem. But they act slowly.

AH : What was attractive about DFM for you after the Ph.D ?

JFJ : That I could continue the work on image processing within the same field, SPM. Also, while working on SPM, I looked for a post-doc position. I finally found one at the [U.S.] National Institute of Science and Technology, which had relations with DFM, because both are metrological institutions. At NIST they also worked with SPM and I could do some image processing there. So, it was a very attractive position for me.

AH : Did they have a big outfit for STM problems at NIST ?

JFJ : Not that big, but they were working on what I would call a high risk project : a "molecular measure machine". The idea was to measure several milimeters across while keeping atomic resolution. At least atomic resolution it is very hard to measure even 100 nanometers across. In addition, they not only wanted atomic resolution but also to use interferometers and things like that in order to make all the accurate measurements. Of course, the more equipment you add, the heavier the construction and much can go wrong. So, it was a high risk project. I actually think it is still running. Obviously they have learned a lot by working on these complicated projects and I contributed a little software.

AH : How long were you at NIST ?

JFJ : One year. I came back and worked at DFM for almost two years.

AH : And you started your own company. Thinking about intellectual property, how have you managed this ? For example, write software at NIST, they presumably get the rights ? How does this work ?

JFJ : Well, I carried most of my software with me, so it was mostly a matter of porting it to run on their Sun machines. The difficulties centered on being able to read and handle their special file formats. So, I wouldn't claim that I made an invention while at NIST.

AH : The experience at NIST rather taught you something about generalizing your software to be used on various other systems.

JFJ : Yes.

AH : Presumably that is a continuous story now that you put it on Windows, as you mentioned.

JFJ : Yes, we jumped from Unix to Windows. The market for Unix was not that big even then and it is not really growing.

AH : So what did you learn from the NIST experience ? What did you take home ?

JFJ : Well, a lot of connections. Very often, the best you get is getting to know people and to discuss problems with them. I recognized some new problems within SPM I hadn't known about before, which of course leads to new ideas for solutions.

AH : For example ?

JFJ : We are getting deep into the way you scan. Scanning with a tip, you might have some friction making the tip bend. When scanning from left to right it bends one way, and when scanning from right to left it bends the other way. At the time most people thought that it was only in the AFM that you have these problems. Probably the most important thing I learnt was from their instrument that was more accurate than any I had ever seen before which enabled us to track very small residual errors. This showed me that the problem just mentioned is more general. We needed algorithms to improve the accuracy in order to measure at the sub-pixel level. Some of the algorithms which we have developed more recently for metrological systems are based on my experience at NIST.

AH : Let me make sure I understand. How would you know about the friction ? From a systematic difference in the scanning this way and scanning that way.

JFJ : Yes, you can see systematic dissimilarities between left to right and right to left.

AH : But that would only work if you stay in one line and just go to and fro, right ?

JFJ : You could do that but you can also take every second line. Usually, if you make an image, it's only from left to right. They were scanning one line left to right and then the second line back the other way, and you can address all kinds of different hysteresis problems. And if the lines are not aligned then you need to analyze how much the odd lines shifted compare to the even lines. That's very technical.

AH : But this would work only for a homogeneous surface, wouldn't it ? You know, if you have a very inhomogeneous surface where every line is different, you can't really tell what is the error and what is a sample, right ?

JFJ : Yes and no. The best thing is of course if you have something like a test structure on a homogeneous surface, but the closer the scan lines are together, the higher is the correlation, so by image processing and correlation techniques, you can actually correct for them. For instance, you can take every second line and make a cross relation and from that see that the line in between had been shifted, maybe just by 0.5 pixel.

AH : I see - and this shift is likely due to the bending of the tip scanning the sample surface ?

JFJ : You can hysteresis in more ways. You can have it in the piezo itself and indeed in other mechanical parts.

AH : And so what you have to do is to identify all the various kinds of hystereses and adjust ?

JFJ : All the non-linearities.

AH : Okay, let's get back to the chronology. The STM project continued at DFM after your post-doc ?

JFJ : Yes, I got a permanent position which included other tasks. I became head of the consultancy section. So, I was able to continue my image processing work, but only part time.

AH : Consultancy for whom ?

JFJ : Everybody who wanted to buy our services. So, of course, one service I wanted to sell was image processing.

AH : Any image processing ?

JFJ : Yes, but we particularly wanted to sell our SPM expertise. People who come to DFM to get some images of a surface and a report. We had a few jobs, and the number of these jobs have increased.

AH : I am curious about the volume of this demand over time, if you have a sense of it. You started in 95 ; presumably there were very few few companies in 95 asking for such services ? Actually, was it companies that came for your services or government bodies ?

JFJ : No, it was university research institutes. They are still the majority but more and more high-tech companies are now using SPMs.

AH : Do you have a sense of how many SPMs there were in Denmark in 1995 ?

JFJ : I think we arranged our first user meeting in 93 or 94. We were only 20 or so ; in 96 maybe 50 people attended our user meeting.

AH : And each person corresponds to one instrument ?

JFJ : No, no, it's hard to say, because each one of those people may have had five, six, seven, eight instruments, or even more. But still there weren't that many in Denmark and there aren't even today.

AH : Can you put a number on it ?

JFJ : No, it's hard for me to put a number on it. I know for certain that DFM has four which I use. One is shared with DTI, the Microelectronic Center and the physical department here have one. I am not actually sure whether it is in working order, but they will eventually build a new one.

AH : They will build a new one ? They don't buy off the shelf ?

JFJ : They build it or buy from the Aarhus group.

AH : The DFM services are for people who come with their data right ? They don't come with an STM, so that, say, you would build the software into their software package.

JFJ : No, we never did that. Of course there are many ways you can use USB expertise. But the kind of job I had was like the one where I simply received some images from a company in America and had to give some feedback on distortions and such things. So, they can bring images that I analyze. Other customers came with surfaces to be measured and analyzed. We SPM-recalled and analyzed.

AH : Working here at the DFM, did you use your software in real time, adjusting while the SPM scanned ? In other words, did you build the software into the SPM ? Or did you measure the data first, and then run the software on the data set ?

JFJ : I never got to build the software into SPM. Before I left for NIST, we had started a project at DME with the intention of integrating our hysteresis algorithms into their software but we never finished. I forget why, but it also had to do with my going to America.

AH : How much of the starting your own company was your own desire to do it and how much was the current pressures in academia ?

JFJ : There was no pressure

AH : None at all ?

JFJ : No, no. You have to fight for what you want.

AH : You wanted to start your own company ?

JFJ : Sure ! And nobody pushed, not at all.

AH : In that case, the market issue we broached briefly before must have been very important. The number of SPMs in existence must be a crucial one for you. But we talked only about the number of SPMs in Denmark, and obviously you want to sell globally.

JFJ : Oh yes. Denmark is very small market. We could almost exist without it.

AH : What precisely are you selling ? The service of unscrambling data or the software ? I have noticed that you do offer free downloads on your website. What's the business rationale for doing that ?

JFJ : Well, we are not doing any conventional marketing, so this is a actually crucial part of the marketing. People can go by themselves and find the product and try it and if they are happy, they might want to buy the full package.

AH : Okay, it's a test, it's a demo.

JFJ : It's a demo. It's very easy to give them the full version, we can just email them a key and they can implement it in ten minutes.

AH : Do you have any sense of how many people download this program ?

JFJ : Yes, around 2000 different people.

AH : 2000 downloaded demos ?

JFJ : Yes. We are preparing a release and once we have it, we will send an email out to to everyone who has downloaded in the past and then I will be able to update on our numbers. It has been a long time since I checked but I think it will be around two thousands.

AH : Presumably the idea is to sell new versions and upgrades ?

JFJ : We are working very gently with this. When they buy, they get one year of free upgrades. It's part of the deal that whenever we have improvements for the modules they bought we send them without further cost for the next year. This is big selling point because we are upgrading very fast. We don't want our customers to have an obsolete product.

AH : So this a long term business plan ? I mean, small businesses don't usually make a profit in the first year, and one couldn't expect that of you either ?

JFJ : That's true

AH : Are you in profit yet ?

JFJ : Yes, right now we are.

AH : Wow, that's great !

JFJ : We had some positive surprises in February [2001]. So, it's quite a good development ; it keeps us busy.

AH : How many people are you ?

JFJ : Only three. I have had a permanent employee for one year now and we have also been using some students who have since left. No we have three permanent people.

AH : And you are all software people ?

JFJ : Yes.

AH : No marketing people ?

JFJ : No, not yet.

AH : So that will happen ?

JFJ : Yes. It has always been part of our business plan. But the timing is not right now.

AH : How do you work out the business structure with the not-for profit institutions that you collaborate with ?

JFJ : It's not a problem. That's why we are here. It's definitely an advantage. It's most important for us to have somebody around us using the software heavily in their work.

AH : They can tell you about the troubleshooting ?

JFJ : Yes, but not only errors, also new ideas and feedback on what they need. That is very important to us and we encourage all of our customers to give us feedback. New ideas are often built into free upgrades.

AH : What's in it for the Danish Technical University to have you here ?

JFJ : I do not know. Of course, we are paying rent here and we can contribute to their visibility, showing that they are helping new companies. Actually, we are talking about the Danish Institute for Fundamental Metrology which is not a part of DTU. It's like DTI, a self-owned technological service institute ; most of their income stems from project money from the government. We have a license agreement with them. They get 5% of everything we sell and they are a part owner.

AH : Are they under pressure to show their relevance for Danish industry ? Is that what you meant by visibility ?

JFJ : Sure, if you can show that a successful company was spun off an academic or government institute the latter would have an easier time getting money later on.

AH : What competition have you got in this field of unscrambling SPM images ?

JFJ : I think we are probably the only company making software exclusively. There are some other companies selling software to go with hardware, the latter being their main business.

AH : Such as Thermo Microscopes, and Digital Instruments ?

JFJ : Thermo Microscopes are only selling software to their own customers, I think. There is a small Spanish company coming up with some software right now. So, I have to consider whether they are a competitor or not. When I started I expected my major competitor to come from the United States. Don Chernov has a company called Advanced. He had something and it was very expensive - it was still in the DOS world. I think it has changed since then and in this respect I don't really regard them as competitors. So right now we are sitting pretty and have only a few competitors. And for those people who really want accurate and serious measurements, the competition is very small.

AH : So you are not worried about people downloading and doing some reverse engineering and so on ?

JFJ : One should of course always pay attention to such issues.

AH : Thank you very much !

Fin de l'enregistrement

Transcription : Arne Hessenbruch

Pour citer l'entretien :

« Entretien avec Jan Friis Jørgensen », par Arne Hessenbruch, 6 mars 2001, Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article119.

—

Entretien avec Jan Friis Jørgensen, par Arne Hessenbruch, 6 mars 2001

Support : non communiqué

Edition en ligne : Sophie Jourdin

GRIESEMANN Jean-Claude, 2001-02-24

Sophie Jourdin — 2011-10-28T14:24:36Z

Jean-Claude Griesemann was trained as a physicist. He has a PhD in plasma physics and joined Renault initially as a specialist on lasers in industrial processing. From 1991 to 1998 he has headed a unit on the fuel cell for vehicles within Research Management (Direction de la Recherche) at Renault.

BERNADETTE BENSAUDE-VINCENT (BBV) : Quelle est votre opinion sur le véhicule électrique ?

JEAN-CLAUDE GRIESEMANN (JCG) : Le véhicule électrique est un concept idéal qui porte dans ses gènes les limites qui définissent son créneau d'application. L'énergie avec une batterie lithium vise à une autonomie maximale de 180-200 Km, avec 4 heures de recharge. Le coût élevé de cette technologie n'a pas encore permis aux constructeurs de dégager une rentabilité vraisemblable. La voie ouverte par Toyota, objet de développements en cours, c'est l'hybride : moteur thermique avec assistance électrique légère pour adoucir les transitions. C'est l'optimum du raffinement électrique sur un véhicule conventionnel.

BBV : Y-a-t-il plus d'espoir du côté des piles à combustibles ?

JCG : Le concept existe depuis Grove (1827) mais les piles à combustibles ne sont entrées en application que dans la seconde moitié du XXe siècle dans les capsules Gemini. C'était très bien adapté. L'hydrogène existe dans le propulseur, l'oxygène existe en tant que comburant des propulseurs ; la pile à combustible utilise ces réactifs pour fournir du courant par migration des ions H+ à travers l'électrolyte et produit de l'eau qui est grandement nécessaire dans une station habitée. L'utilisation d'oxygène pur affranchissait l'électrolyte alcalin du risque de contamination par le dioxyde de carbone.

BBV : Est-il possible de transférer la technique aux automobiles ?

JCG : L'air ambiant contient du CO2. On a utilisé la chaux sodée pour capturer le CO2 : La société ELENCO en Belgique, soutenue par le Centre d'études nucléaires de Mol a construit un autobus utilisant une batterie de ces piles à combustible alcalines : il comprenait une remorque contenant la pile et la chaux sodée. La faillite de la société ELENCO n'a pas permis la venue à terme de ce premier démonstrateur.
En France, un grand programme-cadre de recherche et développement pour l'industrie des transports terrestres (PREDITT) a été lancé en 1991 par le gouvernement français, favorisant un partenariat entre Renault, PSA, le CEA, le CNRS et l'Agence pour l'environnement et la maîtrise de l'énergie (ADEME). Ce programme sur 5 ans fut doté d'un budget de 50 million de FF : 25 millions apportés par l'ADEME et le reste par les partenaires industriels. Gérard Chaumain alors responsable des technologies avancées à l'ADEME (22 Rue Louis Vicat, Paris 15e) a joué un rôle moteur dans ce projet.
Le programme de recherche a été articulé autour de trois questions :

- qu'est une pile à combustible ?
- comment construire une pile à combustible ?
- comment la fabriquer dans des conditions économiques réalistes ?
Le programme de recherche a mobilisé le CEA, 12 laboratoires du CNRS et un institut de recherche privé, sous contrat, la SORAPEC à Fontenay-sous-Bois.
Les résultats furent prometteurs : 1 kW mais pas d'autre matériau pour le catalyseur que le platine. Dans le cadre de cette étude, on a réussi à minimiser considérablement le taux de platine nécessaire. On est passé de 20g de Pt/kW en 1991 à 1g de Pt/kW en 1995.

BBV : Est-ce que la commission européenne a joué un rôle dans ce programme ?

JCG : En 1993, la Commission européenne à Bruxelles soutenait le laboratoire de PETTEN aux Pays-Bas dans la création d'un Brass Board, un banc d'essai, un système roulant pour tester les éléments constitutifs d'une pile à combustibles. Ce projet était en cours de réalisation au Centre nucléaire néerlandais.
Peter Zeegers, scientific officer de la DGXII à la Commission européenne (plus tard il y sera directeur) soutenait de tous ses efforts le désir de passer aux applications. Quelques mois plus tard, fin 93, la Commission lançait un appel d'offres incluant les véhicules à piles à combustibles.
Deux ingénieurs furent recrutés : un électrotechnicien de l'ENSI de Lyon, un électrochimiste du LEPMI de Grenoble qui avait fait un post-doc chez Siemens. Cette petite équipe a travaillé durement et s'est vraiment investie dans le projet.
On a divisé le véhicule en 5 packages :

- piles à combustibles
- système des auxiliaires (qui entoure la pile à combustible)
- réservoir à hydrogène liquide
- motorisation électrique (à l'avant)
- véhicule intégré
Pour chaque package on a identifié trois partenaires potentiels et on a choisi l'un des trois.
Chaque partenaire devait apporter sa contribution financière au projet.
- Pour la pile à combustibles, on a contacté Elenco en Belgique, Siemens en Allemagne, DeNora en Italie, à Milan. Finalement, on a choisi De Nora. [1]
- Pour le réservoir d'hydrogène, on a rencontré Air Liquide en France, Linde en Allemagne, Messer Griesheim en Allemagne. Pour stocker l'hydrogène à –250°C, il faut des réservoirs cryogéniques à haute isolation. Les conditions de sécurité sont drastiques.
- Pour la motorisation électrique, on avait le choix entre les technologies émergentes ou déjà exploitées. Notre recherche portait sur la taille du moteur et son rendement. On a pressenti Siemens, AUXILEC en France (expert en véhicule électrique) et Fichtel und Sachs en Bavière.
- Pour le système auxiliaire, il fallait une expertise en systèmes complexes, dynamique des fluides et thermodynamique ; plus une expérience dans le maniement de l'hydrogène. On a consulté Vickers Shipbuildings Ltd, en Ecosse (VSL), Ansaldo Ricerche en Italie, fabricant d'autobus et de centrales.

Dans tous les cas nos critères de choix étaient :

- prestation maximale au meilleur coût
- compatibilité entre les partenaires
- disponibilité et réactivité
Par exemple, Linde proposait un réservoir plus cher que Air Liquide, lui-même plus cher que Messer Griesheim à 400 000FF. On a choisi Air Liquide, non parce qu'ils sont français mais parce qu'ils offraient une prestation en plus pour la circulation de l'air.
La compagnie écossaise VSL a été écartée car ils avaient déjà signé un accord avec Ballard, une société canadienne concurrente sur le terrain des véhicules à piles à combustible. Pour orienter l'architecture du véhicule on a choisi Volvo car il offrait la simulation numérique qui évitait les tâtonnements.

On a ainsi constitué une équipe de 6 partenaires [2] qui fut agréée par la Commission européenne en 1994. Le budget était de 4.3 millions d'euros (environ 25 millions de FF) pour l'ensemble du projet. La commission européenne versait 2.5 millions d'Euros en trois ans, le reste étant à la charge des partenaires.

Le résultat : Fever, un véhicule qui pèse 2200 kg, capable d'une autonomie de 500km à émissions de polluants nulle, mais dans lequel l'habitabilité n'est pas préservée.
L'équipe technique, chez Renault, était très faiblement dimensionnée (2 ingénieurs et 2 techniciens) puisque, dans un projet multipartenaires, chacun d'eux assume sa part de la charge sectorisée.
Certains partenaires ont fait plus que leur part de travail, en particulier le Centre Energétique de l'Ecole des Mines à Sophia-Antipolis dirigé par Patrick Achard, assisté de Rudoph M. Meyer, qui venait de finir sa thèse. Ils étaient en charge de la validation de la pile à combustible ; ils l'ont expérimentée dans leur labo. Luc Rouvère a conçu le système autour de la pile en faisant un calcul de gestion optimale de l'énergie par simulation numérique.
Les méandres administratives de l'homologation on conduit Air liquide à livrer le réservoir avec un an et demi de retard. Il a fallu obtenir une prolongation du projet de 1997 à 1998 et engager des ressources et dépenses très supérieures à celles du contrat initial.

BBV : Est-ce que la simulation joue un rôle décisif à ce niveau ?

JCG : Oui elle évite bien des tâtonnements.

BBV : Quels étaient les projets concurrents ?

JCG : Que se passait-il dans le monde entre 1994-98 ? En 1994 Daimler-Benz annonce Necar 1 : un camion de 3,5 tonnes avec seulement 2 places. L'hydrogène est comprimé et l'autonome inférieure à 100km.
En 1995, Daimler sort Necar 2 : l'espace libre est plus grand : 6 places, car ils intègrent la pile à combustibles et le système dans le plancher tandis que le réservoir à hydrogène comprimé est logé dans un double plafond.

BBV : Et quel est l'électrolyte utilisé ?

JCG : Dans notre cas c'est un polymère conducteur de protons, un polysulfone fluoré Toutes ces piles sont au Nafion ou a un dérivé de Nafion.
En 1996 Daimler Chrysler présente le Necar 3. Une classe A. La pile est dans le double plancher avec un reformer qui transforme le méthanol en hydrogène. Le reformer c'est un réacteur avec catalyseur dans lequel on introduit du méthanol avec de l'eau et il sort de l'hydrogène, du CO et du CO2 et de l'acide formique. L'avantage c'est que l'hydrogène est produit à bord mais le méthanol est un neurotoxique. Ce véhicule a été présenté au salon de Francfort.
Fin 96-début 97, Daimler Chrysler présente Necar 4, toujours une classe A. Cette fois, ils ont adopté la solution de stockage d'hydrogène liquide à l'arrière. L'effort de R&D consenti à l'époque représentait 900 millions de francs et 100 personnes travaillant pendant 7 ans.

BBV : Y-avait-il d'autres concurrents sérieux ?

JCG : Toyota a sorti RAV 4 : un véhicule à fuel cell avec un prétendu reformer de méthanol. Cela a fait beaucoup de bruit. En 1998, Daimler a pris une participation forte dans le capital de Ballard avec Ford pour une joint venture de 4 à 5 milliards avec promesse de produire un véhicule en 2004. En 1999, Toyota proclame dans un press release : les Fuel cells vehicles existent mais n'ont pas de marché. Nous gardons cette technologie en stand-by en attendant que le marché s'ouvre.

BBV : Chez les Français, qui est en course vers la pile à combustibles ?

JCG : Peugeot avait engagé la recherche initiale avec Renault. Ils ont initié leur programme de recherche appliquée en reprenant certains des partenaires de FEVER. Et comme nous ils ont eu des ennuis avec Ansaldo. Ils ont un excellent service de communication, si bien qu'aujourd'hui ils apparaissent comme les leaders dans le domaine, les maîtres de cette technologie en France.

BBV : Est-ce que le projet est poursuivi chez Renault aujourd'hui ?

JCG : Maintenant le pôle lourd est pris en charge par Nissan avec 100 personnes. Ce fut une expérience passionnante. Tout le monde est fier d'y avoir participé. Un très beau résultat si l'on considère que ce fut le point de départ, l'acte fondateur d'un grand programme de véhicules à piles à combustibles avec Nissan.
Fever est un laboratoire roulant, un mulet de démonstration ce n'est pas un véhicule. On ne peut pas le mettre entre les mains de tout le monde sans formation. Un prototype permet seulement de valider les caractéristiques réalistes d'un concept.

BBV : Quelles sont les voies poursuivies aujourd'hui ?

JCG : La voie du reforming de carburant, méthanol, essence ou kérosène. Tous familiers des constructeurs automobiles. Mais je pense que la solution ultime sera le stockage d'hydrogène. Le problème c'est le refuelling.

BBV : Y-a-t-il des programmes pour équiper des infrastructures routières ?

JCG : C'est une décision communautaire. Il y a des pressions de la part des milieux automobiles, des Etats. Démarche assez bizarre. L'impulsion la plus forte vient des Allemands mais les Verts ne voient pas que le véhicule électrique ne fait que repousser le problème de la pollution sur la production d'électricité propre. Pour produire de l'hydrogène il faut de l'électricité donc peut-être du nucléaire.

BBV : L'objectif 2004 est-il toujours réaliste ?

JCG : Une démonstration est prévue en 2004 en Californie : une petite flotte de 10 véhicules gérés par des instances bien choisies sera mise en circulation et Renault-Nissan enverra 3 véhicules.
Mais force est de reconnaître que le Mandate du zéro emission émis en 1992 par le Clean Air Board de Californie a été sérieusement révisé à la baisse. On acceptera les véhicules hybrides et mêmes le véhicules à gaz naturel bénéficieront d'un crédit. La Californie a fait beaucoup d'ouvertures pour ne pas se déjuger sur la date fixée 2003.

BBV : Le zero emission est-il une utopie ?

JCG : “The zero emission vehicle is a vehicle for which electricity has been produced in the next state”. Les USA produisent l'électricité la plus pénalisante en émissions de polluants. La deuxième électricité la plus sale est celle du Danemark. Elle est produite à partir des fuels lourds très soufrés.
Le centre ECODEV du CNRS a évalué l'émission de CO2 amont et aval pour diverses catégories de véhicules suivant les pays. Le véhicule électrique génère du CO2 pour la fabrication d'électricité. Kangoo électrique conduit à la production de 17g de CO2 par km contre 160 g pour un véhicule à essence. Mais aux USA un véhicule électrique produit 115g de CO2 au km.

BBV : Alors la solution de réformer le méthanol n'est-elle pas plus réaliste ?

JCG : On a 80% de rendement et le bilan global de CO2 n'est pas meilleur que celui d'un bon moteur Diesel. Le bénéfice serait de 15%. Le jeu vaut-il vraiment la chandelle ?

BBV : Ne pourrait envisager d'autres concepts ?

JCG : On poursuit des travaux sur le véhicule à usage partagé, sur le véhicule en libre service.

BBV : Ces alternatives sont-elles utopiques ?

JCG : Pas du tout. En Grande Bretagne 40% des véhicules sont achetés par des loueurs. Les gens louent au lieu d'acheter. Ce n'est pas inintéressant.

BBV : Quels sont alors les verrous qui empêchent l'essor du véhicule électrique ?

JCG : Verrou technologique surtout.

BBV : Le verrou ne serait-il pas social ? Y a t il une demande ?

JCG : Les gens veulent un moyen de transport, pas cher, confortable et générateur d'image positive, ils veulent ne jamais lever le capot. Mais cela peut changer car le symbole de la voiture commence à évoluer. Le volant comme symbole phallique c'est latin. Or nous devenons de plus en plus nordiques dans nos goûts. On conduit calme, d'où le succès grandissant de la boîte de vitesse automatique. Cette évolution des goûts peut amener quelque chose, un changement dans le concept de l'automobile.

BBV : Renault a-t-il entrepris des campagnes de sensibilisation du public pour favoriser les carburants alternatifs ?

JCG : Le seul moyen est de convaincre les policy makers qui influenceront les acheteurs de véhicules particuliers grâce à des incitations fiscales. Prenons l'exemple du GPL, trois fois plus propre que le véhicule à essence. La Direction de Renault a engagé une grande campagne de médiatisation, avec intervention au Parlement, lobbying. Suite à quoi la loi de finance de fin 95 a prévu une baisse de 1F sur le litre de GPL. Cette mesure, entrée en vigueur le 2 janvier 96, a mis le litre de GPL à 2.75 F contre 5.50 pour le litre d'essence. Du coup les chiffres de vente de véhicules au GPL ont augmenté rapidement : de 20 000 à 40 000 en un an et 125 000 aujourd'hui. On a donc multiplié par 6 en 5 ans.
Autant des compagnies que des particuliers achètent ce genre de véhicules pour l'image de marque : Danone et Darty, par exemple.

BBV : Comment voyez vous l'avenir des piles à combustibles dans l'automobile ?

JCG : A court et moyen termes, les véhicules conventionnels vont continuer avec une petite part de marché pour le GPL et le gaz naturel. L'avenir proche c'est l'hybride moteur thermique avec une assistance électrique intégrée. Cela fait gagner en consommation. Et l'objectif premier c'est réduire la consommation.
Le véhicule électrique reste un produit d'image. Le véhicule à pile à combustible ? Peut être, vers 2010. Le marché commencera par les minibus et les transports en commun. En tous cas , tous les constructeurs automobiles investissent parce qu'ils veulent posséder la technologie pour le cas où cela deviendrait le véhicule d'avenir.
Mais ce sera un processus lent de conversion et la conversion ne sera jamais totale. Même les Allemands les plus avant-gardistes ménagent un segment de parc de 15% pour les piles à combustibles.

BBV : N'y-a-t-il pas des moyens d'influencer la demande ?

JCG : Il ne faut pas inverser les objectifs et les moyens. L'objectif est le transport des personnes et des biens, confortable, rapide qui donne satisfaction au client. Le véhicule n'est qu'un moyen et non une fin en soi. L'objectif est de ne pas changer les habitudes de conduite. Le client ne veut pas savoir ce qu'il y a sous le capot. Le véhicule électrique n'est pas satisfaisant parce que la physico-chimie des batteries a trouvé ses limites dans le tableau périodique. Tant que la recharge exigera plus d'un quart d'heure, il ne peut remplir les objectifs de marché large que nous visons.

BBV : Mais si une volonté politique rendait le véhicule plus satisfaisant ?

JCG : La politique nationale ne peut rien car le marché est mondial. A l'heure actuelle Renault-Nissan produit 4 millions de véhicules et l'objectif pour 2010 est 8 millions. Cela nécessite une expansion mondiale sur le marché américain, africain, asiatique...Une faveur fiscale nationale n'est pas un motif assez puissant pour investir trois milliards dans un projet de R&D. La Mégane a coûté 9 milliards d'investissement sur 3 ans, amortis en 5 ans.

BBV : Est-ce le manque de retour sur investissement qui freinent les recherches sur le véhicule électrique ?

JCG : Le retour sur investissement est difficile à évaluer. Notre programme de recherche a eu un résultat modeste mais il a été le tremplin d'un grand projet, engageant plus de 100 personnes. Si dans 10 ans, il n'y a pas de marché c'est un flop. Mais s'il y a un marché ce sera considéré comme un investissement très rentable car bon marché.

BBV : Le véhicule à pile à combustible est donc un futur possible ?

JCG : Qui sait ? Je ne peux pas prédire l'avenir. Politiquement nous n'avons pas le droit d'être absent de la course. S'il y a une chance une seule, alors il faut y aller.

Fin de l'enregistrement

[1] This electrochemical company was founded in 1923 by Oronzio de Nora. Today, De NORA SPA designs and delivers complete plants world wide for electrochemical and electrometallurgical industries.

[2] Ces 6 partenaires sont :

- Ecole des mines (Optimizing operating parameters) was in charge of constructing a test bench and simulation models in order to determine the optimal operating parameters of the fuel cell.
- Ansaldo Ricerche : design, assembly and test of the Power Module.
- Air Liquide in charge of the hydrogen tank, hydrogen recirculation and refuelling facility.
- Volvo TD in charge of i) energy management, ii) battery evaluation and specification, iii) safety study.
- De Nora SPA in charge of the design, manufacture and test of the Solid Polymer Fuel Cell stacks.
- Renault as leader of the project was responsible for the choice of the electric motor and the specification of the air compression system. Renault designed the architecture and assembled the demonstrator.

Pour citer l'entretien :

« Entretien avec Jean-Claude Griesemann », par Bernadette Bensaude-Vincent, 24 février 2001 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article123.

—

Entretien avec Jean-Claude Griesemann, par Bernadette Bensaude-Vincent, 24 février 2001

Lieu : France

Support : non communiqué

Edition en ligne : Sophie Jourdin

FUJITANI Shin, 2002-09

Sophie Jourdin — 2011-10-28T12:13:19Z

Shin Fujitani

Research Manager, Sanyo Electric. Co. Ltd., Soft Energy Company, R&D Division, Energy R&D Center

BERNADETTE BENSAUDE-VINCENT (BBV) : In which discipline did you take your degree ? your Ph D ?

Dr. SHIN FUJITANI (DF) : I took a doctorate in metallurgy.

BBV : How and when did you come into industrial research ?

DF : I joined Sanyo in 1982 just after I finished graduate school.

BBV : Which field is your specialty ?

DF : Metallurgy, electrochemistry and battery.

BBV : Did you specialize in one field or did you change your research subject ?

DF : Before I joined the company, I had majored in metallurgy. Since I joined here, I have been engaged in battery R&D based on metallurgy and electrochemistry.

BBV : Did you conduct your research in contact with university or national laboratories ?

DF : I have worked on governmental contract under a collaboration with a national laboratory for about 10 years.

BBV : How do you plan your research ? What is a long term research project for you ?

DF : Short term projects are planed in accordance with demands from existing markets. Long term ones are planed to help the short term projects going successfully. These may be a general idea, which my current R&D field, battery technology, has followed in the company.

BBV : We learn a lot from success but failures are even more illuminating for historians. Would you tell us about a case of failure in your career or in your field ?

DF : Among many failures, the most significant in my view is the 10 year project that I mentioned above, conducted in collaboration with a nationaly laboratory. I certainly obtained new chemical views and new materials but they found no applications. R&D in a targeted area did not work well and finally this project did not result in important industrial contributions.

BBV : Could you give me a few details about the organization of your laboratory : how many people are working here ? Is there a clear division of labour ? of research themes ? What are the disciplinary affiliations of the people in your laboratory ?

DF : I am afraid that I cannot tell you how many people are working here because of confidentiality. People are divided according to the specific theme they are working on, so that their responsibilities are clearly defined.
The researchers in my lab. have different disciplinary backgrounds, in electrochemistry, in chemical engineering and in a variety of materials sciences, organic for some of them and inorganic for others.

BBV : Where do the financial resources come from ? Do you have internal reporting ? Regular meetings ?

DF : The financial resources are all covered by the company. Therefore, I am obliged to report results on my R&D activities sometimes in the regular meeting weekly, monthly and annually.

BBV : Do you have financial constraints in purchasing instruments ?

DF : I am afraid that the notion of “financial constraints” is a little vague for me. The budget of R&D is determined for each purpose, e.g. ; for purchasing consumable supplies and materials, for investing plant and machinery, for the expenses of business trips , etc., and the total amount is determined in consideration of cost performance and risks of the R&D to the business, and the business conditions as well.

BBV : Publishing or patenting ? What is the priority ?

DF : Patenting is the priority. Ne number of patents largely exceed the number of publications in journals as well as of oral presentations in conferences.

BBV : Do you attend international conferences ? Which ones ? In which countries ?

DF : Yes we attend conferences everywhere as long they cover interesting topics in my field. Personally, I have attended conference in the USA and Canada as well as in some European countries.

BBV : Do you have international collaborations ? In which countries ?

DF : Some R&D collaborations in EU and US are now underway.

BBV : Did you notice different cultural research styles ?

DF : Yes, I did. Research abroad starts at a much more fundamental level than our researches in Japan, Their value and their results are consequently often more praised and amired than our Japanese contributions.

BBV : Do you think that the materials generic perspective, as it is based on a system approach between structure, properties, performances and process, is useful for your research ?

DF : Yes, I think it is extremely useful as long as it helps defining in some way the potentialities and limitations of the materials' functions for specific application devices, e.g. for battery performance in my case.

BBV : What is the place of Materials research in your country ? In terms of economic importance and social prestige or public image ?

DF : The centers where Materials researches are performed are scattered all over Japan, including universities, firms and public institutions. There are two major poles of national laboratories : one is in Tsukuba, Ibaraki prefecture 1hr away by train from central Tokyo and the other one is found in Ikeda, Osaka prefecture.

BBV : Where would you locate the leading centers in your field ?

DF : My lab is now located in Kobe, Hyogo prefecture. I think it is a good candidate for ranking among the leading centers in the field of batteries. Its importance may partly be due to the fact that Kobe is one of the most attractive big cities in Japan for educated people.

Fin de l'enregistrement

Pour citer l'entretien :

« Entretien avec Shin Fujitani », par Bernadette Bensaude-Vincent, septembre 2002 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article120.

—

Entretien avec Shin Fujitani, par Bernadette Bensaude-Vincent, septembre 2002

Lieu : Sanyo Electric.Co.Ltd., Soft Energy Company, R&D Division, Energy R&D Center

Support : non communiqué

Edition en ligne : Sophie Jourdin

BOILOT Jean-Pierre, 2000-12-12

Sophie Jourdin — 2011-10-28T12:00:58Z

Jean-Pierre Boilot worked on b-alumina in the 1970s and subsequently on ionic conductors within the framework of chimie douce.

BERNADETTE BENSAUDE-VINCENT (BBV) : Quel fut votre parcours individuel ?

JPB : Je suis entré au laboratoire Collongues en 1971, étant assistant à l'Ecole de céramique de Sèvres où j'enseignais la chimie. Mon sujet de thèse portait sur l'alumine-b plus exactement sur les gallates. On cherchait à améliorer la conduction ionique en remplaçant l'aluminium par du gallium. On connaissait, bien sûr, les travaux de Yao et Kummer et on savait déjà échanger les ions sodium par d'autres. Mais ceci n'a constitué qu'un chapitre de ma thèse qui devait en avoir 5 ou 6.
Après j'ai eu un rôle très particulier : travailler à l'interface de la physique et de la chimie. Cette expérience de collaboration de la physique et de la chimie du solide, c'était une innovation. Seul Yves Le Car avait commencé avant moi. Lui avait un financement industriel, avec CGE qui est devenu Alcatel. Cette collaboration est issue de discussions entre Robert Collongues et André Guinier qui était responsable d'un groupe de physique du solide à Orsay au bâtiment 510. Le Car a commencé à faire de la diffusion des rayons X, organisation des ions de conduction dans alumine-b. J'ai poursuivi dans cette voie. La collaboration s'est étendue. Je passais 50% de mon temps au labo Collongues et 50% en physique chez Guinier et chez Jérôme, un autre groupe de physique du solide qui faisait de la RMN. Une grande partie de ma thèse concernait des problèmes fondamentaux : comment les ions s'organisent, ordre désordre, stœchiométrie.

BBV : Quels étaient les modèles théoriques à l'époque ?

JPB : Peu de choses pour comprendre les mécanismes de conduction. C'est venu plus tard. Les physiciens durs ont attaqué le problème plus tard.
J'ai soutenu ma thèse d'Etat en 1975 devant un jury très impressionnant : Jacques Friedel, Jean Rouxel, Michel Fayard, qui est devenu directeur du secteur chimie au CNRS, Jeanine Théry et Robert Collongues. Je me souviens avoir été mauvais, je n'étais pas fier de moi.

BBV : Avez-vous poursuivi sur alumine-b ?

JPB : Oui de 1975 à 82 j'ai travaillé avec Gaston Colin, cristallographe et avec Philippe Colomban qui est arrivé au labo Collongues. Je l'avais eu comme étudiant à l'école de céramique. On a travaillé essentiellement sur deux aspects : alumine-b stœchiométrique et alumine-b''. Même type de base : compréhension, organisation des ions en utilisant les paramètres fondamentaux du solide : répulsion entre ions, transition au désordre etc.

BBV : Y avait-il alors une communauté française de chercheurs sur l'alumine-b ?

JPB : Oui, il y avait des séminaires organisés ici à Polytechnique par Bernard Sapoval->http://pmc.polytechnique.fr/bs/english.html] et Hervé Arribart. Les gens ici ont commencé à travailler sur l'alumine-b avec des porteurs de protons et ils utilisaient la RMN.
Donc si l'on fait le bilan de ces 10 ans, il y a deux caractéristiques propres à ce sujet

- C'étaient les premières recherches fondamentales menées parallèlement à la recherche industrielle car CGE en France, Ford, General Electric aux USA faisaient des recherches plus appliquées sur les accumulateurs sodium-soufre. C'était particulièrement motivant de voir qu'il y avait des possibilités d'application.
- Deuxième caractéristique : c'était la possibilité de travaux à l'interface physique-chimie. Ces deux aspects là se retrouvent plus tard dans les recherches sur les supra-conducteurs au cours des années 90.

BBV : Aviez-vous des contacts avec l'industrie ?

JPB : On avait des contacts avec CGE et on allait parfois à Marcoussis voir M. Dumas de CGE. Mais on faisait de la recherche fondamentale.
Des contacts avec l'industrie, il y en avait sans doute au labo Collongues. Mais je n'étais pas au courant. Par contre, au laboratoire Collongues, Didier Goureyet était plus proche des préoccupations industrielles, tout en étant en recherche fondamentale.

BBV : Avez-vous ressenti un certain pessimisme industriel sur l'alumine-b au cours de ces années ?

JPB : Non, il y eut une effervescence de 1970 à 76. Le pessimisme est venu après. Il y avait peut être des problèmes pour les gens qui ne travaillaient pas sur le sujet. C'est faux de dire qu'il y avait un pessimisme dans les années 70. Pour les années 80, c'est une autre histoire. Plus de problème d'énergie, d'autres problématiques sont arrivées : utiliser des systèmes. On savait que les batteries sodium-soufre ne seraient pas commerciales. Elles ne le seront peut-être jamais. Donc du point de vue industriel, c'était un tout petit peu moins motivant.

BBV : Avez-vous participé aux congrès internationaux des années 70-80 ?

JPB : Bien sûr je pourrai vous donner la liste. C'est un autre aspect important : il y avait une compétition internationale, essentiellement avec les Américains, avec les gens de General Electric - Roth - et les gens de Bell Telephon. J'ai commencé à participer en 1976 Schenectady ; 1979 Lake Geneva (USA), Gatlinburg (Tennessee) en 1981, Grenoble en 1983, Lake Tahoe en 1985 ; Garmisch en 1987. Outre cette série des Solid State Ionics il y avait Rome (1976) et Saint-Andrews en Ecosse, en 1978. A chaque fois on avait des papiers dans ces conférences.

BBV : Y-a-t-il eu une évolution ou réorientation de vos recherches sur cette période ?

JPB : On a pousuivi les mêmes pistes de recherche sur les deux alumines-b.
Philippe Colomban, chimiste, s'est consacré à l'élaboration des mono-cristaux d'alumine-b. Seuls deux groupes au niveau international savaient faire la synthèse des alumines-b : Colomban au laboratoire Collongues et Farrington chez General Electric. C'était un procédé à haute température avec quelques subtilités chimiques pour parvenir à faire l'alumine stoechiométrique. Mais il n'y eut pas de brevets sur les mono-cristaux. L'objectif était purement fondamental car les applications se faisaient sur un milieu polycristallin, céramique.
Parallèlement à partir de 1978, on a commencé à travailler sur d'autres conducteurs ioniques qui pouvaient remplacer l'alumine. Ils faisaient partie d'une série qu'on appelait nasicons : c'étaient des phosphates ou des phospho-silicates avec des ions sodium.
Le choix du sodium repose sur des arguments très simples : il faut un ion monovalent, de la bonne taille. S'il est trop gros il ne diffuse pas facilement ; s'il est trop petit (cas du proton ou du lithium) il vient se coller sur le réseau ; ou on a une interaction trop forte avec les anions (les chimistes disent trop polarisants). Les meilleurs ions sont Na+ et Ag+. Ensuite le choix dépend des applications. A cette époque là le problème était le stockage d'énergie, on visait des accumulateurs de haute puissance pour faire du stockage. Les critères de densité d'énergie massique portaient le choix sur les éléments légers, donc le sodium plutôt que l'argent.

BBV : Est-ce que la crise d'énergie a infléchi les recherches au labo Collongues ?

JPB : Peut-être mais à cette époque j'étais trop concentré sur ma thèse et je n'avais pas de vue d'ensemble. Pour revenir aux applications, les nasicons ont eu moins d'intérêt car ils sont moins stables, ils résistent moins bien au sodium liquide. Ils n'ont pas eu le succès de l'alumine-b mais des gens travaillent encore dessus. Il y a eu beaucoup de travail sur cette famille : diversité de compositions et de phases. Elle présente un intérêt pour la compréhension des paramètres fondamentaux du solide mais moins que l'alumine-b.

BBV : Rétrospectivement considérez vous que ce travail sur les nasicons a été positif ?

JPB : Oui on aurait peut-être pu arrêter un peu plus tôt. On a travaillé là dessus de 1978 à 1984 mais toujours en parallèle avec l'alumine-b. C'est un travail qui se faisait à Polytechnique où je suis venu en 1981. C'est un sujet qu'on a développé ici avec Colomban, toujours en liaison avec les physiciens du solide (Collin) d'Orsay dans le groupe de Robert Gomès qui avait pris la succession de Guinier.
Après on a pris un virage vers les sols-gels. La transition s'est faite par le biais des nasicons. On avait dans l'idée d'élaborer des phases amorphes pour conducteurs ioniques. Elles étaient dérivées du nasicon. On a préparé les premiers verres organo-minéraux en s'inspirant des conducteurs ioniques type nasicons. Notre modèle à nous était le conducteur ionique. Puis on a eu des résultats intéressants sur ces matériaux, sans rapport avec la conduction ionique. Ces hybrides organo-minéraux, à la frontière entre organique et minéral sont faits à température ambiante avec une chimie douce.

BBV : N'est-ce pas un paradoxe que de la chimie à haute température du labo Collongues sorti une chimie à température ambiante ?

JPB : Oui à la même époque Jacques Livage faisait des gels V205.

BBV : Qu'est-ce qui a motivé votre virage vers les verres ?

JPB : Du point de vue industriel, l'alumine-b c'était moins motivant et, du point de vue fondamental, on avait fait le tour. De plus, je démarrais un groupe ici à Polytechnique, c'était le moment de passer à un nouveau projet.

BBV : Est-ce que ce virage vers les verres organo-minéraux a changé votre place dans la recherche ?

JPB : Au niveau du CNRS, non, car on appartient toujours à la famille chimie du solide. Mais on a eu des contacts industriels nouveaux avec Saint-Gobain (Silor). Bien sûr pendant deux ans, on a eu un peu de ralentissement dans la production de publications. Mais le virage se fait bien.

BBV : Quelles sont les activités de votre laboratoire actuellement ?

JPB : Actuellement on est toujours sur la chimie douce. En plus des hybrides organo-minéraux, on travaille sur des objets nanométriques. On part de molécules et on essaie de construire des solides à partir de ces molécules. Ce sont essentiellement des matériaux pour l'optique : lasers ou stockage de l'information optique.

BBV : Quelles sont les techniques que vous utilisez ? Sont-elles totalement différentes de celles qu'on utilisait au laboratoire de Collongues ?

JPB : C'est de la chimie classique avec des béchers mais pas de haute température. C'est bien différent des labos d'alumine où on avait des fours à 2000°C. Le labo Collongues était surtout tourné vers l'élaboration de matériaux alors que maintenant on fait surtout de la caractérisation. Comme maintenant on dispose de nombreuses techniques, on peut faire des thèses sur la caractérisation avec peu de chimie.
Ce que m'a appris l'alumine-b c'est qu'il faut faire de la chimie. C'est le matériau qui est intéressant. C'est le message le plus important. Toutes les avancées qu'on a eues au laboratoire Collongues, c'est parce qu'on a su faire de la synthèse de matériaux avant et mieux que les autres. Notre premier travail est de faire de l'innovation en matériaux, mais on a beaucoup de collaboration en physique.
Notre troisième thème est la pile à combustible. Il est arrivé avec un ancien du laboratoire de Collongues : Philippe Barboux. Il travaillait sur les films minces de céramique et prépare maintenant des membranes conductrices ioniques pour les piles à combustibles. C'est donc un retour à la tradition d'origine.
Mais il y a un lien entre les verres, les particules nanométriques et les piles à combustibles. Ce sont toujours des procédés à basse-température. On travaille sur la diffusion de molécules comme autrefois on travaillait sur la diffusion des ions.

BBV : Combien de personnes travaillent dans votre groupe ?

JPG : Actuellement notre groupe de chimie du solide comprend 10 personnes et il est l'une des composantes de l'UMR-CNRS intitulée Laboratoire de Physique de la matière condensée qui comprend 50 personnes.

BBV : Quels sont vos liens avec l'étranger ?

JPB : Nous avons gardé des relations avec Bruce Dunn de UCLA (nous avons ici un chercheur permanent qui a fait son post-doc là bas). Nous avons également une collaboration avec un laboratoire allemand. Pas de programme européen, c'est trop de paperasses.

BBV : Comment voyez-vous la chimie du solide française sur la scène internationale ? Est-ce qu'elle n'a pas d'une certaine manière fait obstacle à l'essor d'une science des matériaux en France ?

JPB : C'était suite au démarrage de la physique du solide. Il y a avait a deux pôles de chimie du solide en France, celle de Hagenmuller à Bordeaux et celle de Collongues à Paris. L'une plus mandarinale que l'autre. Des gens comme Rouxel, je les mets dans la famille Hagenmuller. En fait, si on prend les labos actuels de chimie du solide, ce sont tous des descendants d'Hagenmuller ou des descendants de Collongues.
Les deux écoles sont tournées vers la science fondamentale plus que vers les applications. C'est totalement différent de l'approche science des matériaux aux USA. Elle n'existe pas en France. L'approche Materials Science est plus tournée vers les applications. En France, il y a eu beaucoup de recherche fondamentale. L'originalité française n'est pas dans la collaboration avec l'industrie mais dans l'approche physique, dans la collaboration entre chimistes et physiciens du solide. Je défends l'approche française. Si les gens avaient été très proches du milieu industriel, je ne crois pas qu'on aurait été aussi forts en chimie du solide.

BBV : Peut-on associer une coloration politique à cette discipline ?

JPB : Traditionnellement en France, les physiciens sont plutôt à gauche et les chimistes plutôt à droite. Quant à la couleur de ces deux écoles de chimie du solide, je dirais que Hagenenmuller était un gaulliste bon teint ; il serait plutôt proche de Pasqua aujourd'hui ; Collongues, lui, était plutôt centre droite, bon vivant.

Fin de l'enregistrement

Pour citer l'entretien :

« Entretien avec Jean-Pierre Boilot », par Bernadette Bensaude-Vincent, 12 décembre 2000 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article121.

—

Entretien avec Jean-Pierre Boilot, par Bernadette Bensaude-Vincent, 12 décembre 2000

Lieu : Ecole polytechnique, Palaiseau, France

Support : non communiqué

Edition en ligne : Sophie Jourdin

LIVAGE Jacques, 2001-01-04

Sophie Jourdin — 2011-10-28T11:49:52Z

Jacques Livage

Bernadette BENSAUDE-VINCENT (BBV) : Quel itinéraire vous a conduit de vos débuts dans un laboratoire de chimie des hautes températures à la « chimie douce » à température ambiante ? de la chimie du solide aux sol-gels ?

Jacques LIVAGE (JL) : D'abord mon origine n'est pas le laboratoire Collongues. Je l'ai rejoint dix ans après le début de ma thèse et à la suite d'un post-doc à Oxford. Après une formation de chimiste à l'Ecole de Chimie de Paris, j'ai préparé une thèse sur la zircone obtenue par précipitation. Ensuite je suis allé à Oxford pour étudier la résonance paramagnétique électronique - ce qui est un thème de physique. C'est en revenant que j'ai rejoint le laboratoire de Collongues.

BBV : En quelle année ?

JL : Je pense que c'était vers 1972 quand Collongues est venu s'installer à l'Ecole de chimie de Paris. J'étais sur place. Je ne connaissais pas a priori l'historique du laboratoire de Collongues. Alors pourquoi ai-je travaillé sur la chimie douce ? Il y a deux raisons.

- Cela tient à une raison personnelle. Au retour d'Oxford j'ai été journaliste scientifique à l'Usine nouvelle, à La recherche et journal Le Monde. Et c'est une idée que j'avais et que j'ai développée dans un article du Monde.
- La deuxième raison est opportuniste. Quand je suis arrivé chez Collongues, j'avais un contrat avec Kodak pour la réalisation de dorsales antistatiques qui étaient des oxydes de vanadium ayant des propriétés électriques. Il s'est avéré que pour pouvoir déposer cet oxyde, il était très commode de fabriquer des gels. C'est pourquoi je suis passé des hautes températures qui ordinairement servent à déposer des couches minces à la chimie douce. C'est donc une problématique industrielle qui a fait que je suis passé d'un thème haute-température à la chimie à température ambiante.

BBV : En arrivant chez Collongues, travailliez-vous sur contrat industriel ?

JL : Oui, il s'agissait d'un contrat Kodak qui portait sur des problèmes de mobilité électronique et la RPE que j'avais étudiée à Oxford est adaptée à l'étude des électrons. Donc j'avais une technique adaptée au problème.

BBV : Avez-vous pris des brevets ?

JL : Il y a eu des brevets pris. Malheureusement Kodak a pris les brevets sans nous en parler. Cela ne s'est pas très bien passé avec Kodak. Mais c'est un procédé qui a été commercialisé et qui est toujours utilisé actuellement. Toutes les pellicules que vous achetez sont faites de cette façon.

BBV : Avez vous continué dans ce domaine ?

JL : Oui on a continué, sans Kodak. Du moins sans Kodak France, en travaillant parfois avec Kodak Etats-Unis. C'est ce sujet là qui m'a fait découvrir les gels que personne n'étudiait à l'époque. Comme c'est un état de la matière qui est assez amusant, je me suis lancé dedans. Et il se trouve qu'en même temps que je travaillais sur les gels d'oxyde de vanadium, les verriers travaillaient sur les gels de silice. On s'est rencontré et puis on a travaillé ensemble.

A ce moment-là, du côté américain, il n'y avait pas grand monde. La Materials Society à Boston comptait une cinquantaine de personnes, pas plus. En France, on a créé un groupe sol-gel au CNRS qui regroupait une quinzaine de laboratoires français. C'était dans les années 80-90. C'était vraiment le démarrage : on rassemblait des laboratoires de chimie organique et de chimie minérale. Il y a eu des séminaires, des écoles d'été. Ensuite, avec des collègues allemands, on a fait un groupe européen et ensuite ça s'est diversifié.

Le domaine s'est constitué d'abord avec les verriers (les laboratoires de recherche sur le verre qui étudiaient les gels de silice). Ensuite se sont joints les céramistes dans le domaine de Materials Science qui ont beaucoup exploité cela pour fabriquer des céramiques. Et maintenant la voie la plus prometteuse ce sont les hybrides. Par la chimie, à température ambiante, on peut mélanger de l'organique et du minéral, en gros tous les intermédiaires entre du plastique, du plexiglass et de la silice, du verre. Et parmi ces matériaux hybrides, il y a un petit volet qui ne s'est pas encore développé : celui où au lieu de l'organique on a affaire à du biologique. Il s'agit d'insérer des enzymes, des cellules, des bactéries, des choses comme ça et de les faire travailler dans du verre.

BBV : Quelles peuvent être les applications de ces hybrides ?

JL : Pour ces matériaux hybrides ce sont les applications optiques qui sont actuellement en plein essor. On met des colorants organiques dans du verre. En fait, il y a des applications réelles, commerciales : typiquement des films minces sur du verre . Il y a pas mal d'industries qui ont lancé des départements sols-gels, par exemple le CEA.

L'oxyde de vanadium a des applications multiples :

- semi-conducteur on l'utilise en film mince pour les dorsales antistatiques. C'est facile on l'étale au pinceau. Le premier brevet pour l'application en couche mince est un brevet allemand (à Iena) de 1939. Mais le procédé ne fut commercialisé qu'en 1959
- c'est l'un des rares matériaux minéraux qui présente un comportement cristal liquide
- on l'utilise comme matériau d'électrode dans les batteries au lithium. Il a un fort potentiel, 3 volts et se laisse mettre en couche mince. Il est donc envisagé pour les portables ;
- au Japon et aux USA on l'utilise aussi comme solvant pour des liants.
- Une application plus classique mais pas encore commerciale concerne l'affichage électrochrome comme l'oxyde de tungstène.

BBV : Vous avez toujours travaillé en étroite collaboration avec l'industrie. Quelles sont les modalités de votre collaboration ?

JL : C'est essentiellement du financement de thèses et de post-doc. Actuellement les brevets sont pris par des industriels avec les noms des auteurs. Les brevets, les licences d'exploitation ce n'est pas nous. Nous n'en retirons aucun bénéfice financier. Nous les bénéfices que l'on a c'est

- que l'industrie finance des post-docs,
- qu'ils embauchent pas mal de gens qui sortent du labo. C'est quand même important pour un laboratoire de recherche et de formation.

BBV : Dans quelle mesure ces liens avec l'industrie ont-ils orienté le cours de vos recherches ?

JL : Au début, on l'a vu, c'est un intérêt industriel qui m'a aiguillé vers les gels. Mais après je ne pense pas qu'il y ait eu de virages. Les enjeux des gels sont très importants pour l'industrie et on était un des rares labos à faire de la recherche fondamentale en ce domaine. En fait c'est toute la chimie des solutions aqueuses. Toute l'industrie des céramiques, des catalyseurs des pigments utilisent déjà ces procédés mais n'en ont pas la science. On a plus apporté un savoir faire, une compréhension, une matière grise que des solutions à des problèmes directs.

BBV : Quelles sont les opérations que vous faites avec ces gels ? Quel genre de techniques utilisez-vous ?

JL : La caractérisation des gels n'est pas facile. Ce sont des systèmes qui ne sont pas cristallins.. La technique la plus importante c'est la RMN et puis l'absorption X les XAS.

La première étape c'est l'élaboration. Faire un gel c'est comme une mayonnaise, il faut le coup de main et puis il faut comprendre le pourquoi et le comment. On a un gel dans un flacon. C'est joli mais pour savoir ce qu'il y a dedans la deuxième étape c'est la caractérisation et puis après il faut voir s'il n'a pas de propriétés intéressantes. Les propriétés essentielles qu'on étudie au laboratoire sont des propriétés optiques et électriques.

BBV : Allez-vous jusqu'à l'étape de la fabrication de prototypes ?

JL : Prototype de laboratoire, non sophistiqué, oui. Mais pas les prototypes industriels. On n'est pas du tout équipé pour ça. De plus, je ne connais pas les besoins économiques. On a déposé une quinzaine de brevets sur 5 années. Mais toujours pris par les industriels. La seule fois où j'ai pris un brevet d'Etat par l'ANVAR cela a bloqué une collaboration avec Saint-Gobain.

C'est peut-être une politique personnelle mais j'ai choisi de faire de la recherche fondamentale et l'institution nous juge sur cette science.

Notre point fort c'est plutôt la matière grise. C'est de la chimie fondamentale. La chimie la plus répandue dans le monde est la chimie des solutions aqueuses. Du point de vue industriel c'est évidemment la moins chère, la plus simple. Et curieusement les connaissances théoriques là dessus sont beaucoup moins développées qu'en chimie organique.

BBV : Quels sont les problèmes théoriques soulevés par les gels ?

JL : Le problème essentiel est de savoir quelles sont les espèces que l'on a dans la solution. En général on n'a pas une espèce mais un mélange, très fugace donc des dynamiques, des cinétiques très rapides. Il n'est donc pas évident de savoir qui est important dans un bécher. Une fois que l'on a compris les mécanismes on peut maîtriser le système et fabriquer ce que l'on veut.

BBV : Comment nommer cette chimie ?

JL : "Chimie des hautes températures", c'était exclu vu qu'on travaille à température ambiante. "Chimie du solide" ne convenait plus, vu que les gels c'est de la matière molle.Chimie de la matière condensée c'était le pendant de la physique de la matière condensée pratqiuée au laboratoire de De Gennes.

BBV : Dans quelles circonstances avez vous lancé l'expression « chimie douce » ?

JL : Chimie douce est une expression que j'ai avancée du temps où j'étais journaliste scientifique. C'est une époque où j'écrivais un article dans Le Monde tous les mois. C'est le titre d'un article publié le 26 octobre 1977 dans Le Monde. C'était au moment du choc pétrolier, des problèmes d'énergie. L'idée était la suivante : ce que l'homme ave l'industrie fabrique à des hautes températures, la matière vivante le fabrique à température ambiante. Il y avait donc peut-être quelque chose à apprendre de ce côté là.

BBV : C'était donc une inspiration biomimétique ?

JL : Tout à fait. Absolument.

BBV : Quel est le devenir de cette expression chimie douce ?

JL : L'expression a été reprise facilement, indépendamment de moi. Dans les milieux anglo-saxons on parle de « chimie douce » en français et non de soft chemistry. De toute façon aux USA tous ces secteurs de chimie du solide, de la matière condensée etc sont couverts par l'ombrelle Materials Science.

Sol-gel n'est que l'un des aspects de la chimie douce. Elle comprend aussi la biominéralisation, les composés d'intercalation. Rouxel avait coutume de distinguer deux classes de composés en chimie du solide :

- à précurseur moléculaire (par précipitation)
- à précurseur liquide comme les argiles ce sont les composés d'intercalation.

La chimie douce suppose toujours une phase liquide : d'où la mobilité des ions.

BBV : Dans quelle communauté êtes-vous inséré. Dans quel journaux publiez-vous ?

JL : Dans des revues de physique, le Journal of Solid State Chemistry ; Chemistry of Materials. Il existe bien un Journal of Sol-Gel Science and Technology mais il n'a pas acquis le prestige des journaux de chimie des matériaux.

Tous les deux ans, nous avons un congrès de la communauté sol-gel. Le premier a eu lieu en 1981 en Italie. 300 ou 400 personnes se réunissent. Si l'on compte que chaque laboratoire envoie environ deux personnes on peut évaluer la communauté à 3 ou 4000 chercheurs.
Les pays forts en ce domaine sont les USA (verriers et céramistes), la France et le Japon. Puis l'Allemagne, la grande Bretagne et l'Italie.

BBV : Avez vous des contacts avec la chimie des colloïdes ?

JL : Peu de contacts. La chimie des colloïdes est plus orientée vers la recherche fondamentale sur les problèmes de surface. Sol-gel, c'est très industriel. Notre chance c'est d'intéresser l'industrie tout en faisant des recherches pas trop appliquées.

BBV : Quels sont les effectifs globaux de votre labo ?

JL : Le laboratoire de chimie de la matière condensée appartient à une UMR CNRS intitulée matériaux inorganiques. Elle comprend 100 personnes en trois unités rassemblées sur la montagne Sainte-Geneviève. L'équipe de Chimie de Paris avec Noël Boffier qui fait des batteries ; l'équipe de l'ESPCI avec Philippe Bosch, céramiste ; et notre groupe sol-gel ou chimie de la matière condensée. L'intérêt de cette union c'est 1) qu'on développe une politique commune et ainsi on évite la concurrence ; 2) on a une bonne implantation pour le recrutement des étudiants. J'enseigne à l'ENS et Clément Sanchez à l'X ce qui permet de recruter. Sol-gel n'est pas encore un sujet académique et les jeunes ont tendance à aller vers ce qu'ils ont appris à l'école. Nénamoins les sols-gels attirent les jeunes. Ce qui dans ce temps de pénurie est un gros avantage. On a 15 thésards en moyenne. C'est un labo qui est jeune la moyenne d'âge est inférieure à 40 ans.

BBV : Quelle est la part de l'industrie dans le financement de votre laboratoire ?

JL : 1/3 vient de l'Etat et 2/3 de l'industrie mais ce ratio n'inclut pas les salaires de chercheurs qui viennent de l'Etat. On a aussi beaucoup de contrats européens. La gestion est assurée au niveau central par Jussieu.

BBV : Vous sentez vous appartenir à une communauté de chimistes ou de materials science ?

JL : Non on est clairement chimiste. En France il n'y a pas de Materials Science

BBV : Comment expliquez vous l'échec des tentatives françaises pour constituer quelque chose comme un secteur science des matériaux ?

JL : Il y a eu des efforts faits par le CNRS quand il était question de faire des commissions regroupant physiciens et chimistes. J'étais à l'époque chargé de mission pour chimie et j'ai une des réunions avec mes homologues pour la physique. Mais ça n'a jamais marché. Le public n'a pas suivi. Je pense qu'il y a eu de très bonnes collaborations entre la physique et la chimie. Le CNRS a fait plusieurs tentatives.C'est l'université qui a fait blocage. Blocage dans les structures plus que dans les mentalités. Dans les structures universitaires on est dans des départements différents. La carrière d'un physicien ne dépend pas de celle d'un chimiste.

Ce qui ne veut pas dire qu'ils ne travaillent pas ensemble. Il y a beaucoup de collaborations Par exemple ce que j'ai fait sur les cristaux liquides c'est avec des physiciens d'Orsay. Pas mal de choses en électrochimie, sur les batteries aussi avec des labos de physique mais on vit dans des commissions séparées, au CNRS et à l'Université. Donc ce sont des milieux qui ne sont pas amenés à vivre ensemble. On ne trouve rien comme ces unités aux Etats Unis qui regroupent physique, chimie et mécanique.

Par contre ce qu'on a fait avec les physiciens ce sont des filières d'enseignement, des filières matériaux. Curieusement elles ne se trouvent pas tellement dans les grandes écoles. Mais dans les universités à Montpellier, Bordeaux, Nantes. La demande est profilée en liaison avec la demande industrielle. On recrute à Bac+2 et on les porte à Bac+5. Il y a des industriels parmi les enseignants et des stages en entreprise. Il y a aussi quelques instituts matériaux : à Nantes, Strasbourg, où il y a à la fois des physiciens et des chimistes.

BBV : Quel est le contenu de l'enseignement de matériaux ?

JL : Il est orienté sur trois dominantes. Les polymères, les métaux et les céramiques.

Mais surtout il existait une forte communauté chimie du solide qui occupait déjà la place. Historiquement elle est née avec Hagenmuller et Collongues. C'est là que la chimie minérale est devenue chimie du solide. Les deux familles ennemies (les écoles de Chaudron et de Chrétien) se sont réconciliées par l'intermédiaire de leurs élèves : Hagenmuller et Collongues. Deux personnes fondamentales pour le développement scientifique et pour le fait qu'elles se soient entendues ensemble. Ils ne se sont pas tirés dans les pattes. Ils se sont épaulés. Ils ont été capables de faire une politique scientifique commune. Ce sont deux personnalités très différentes, deux styles différents avec des thèmes de recherche différents. Je crois que c'est là que la communauté s'est soudée avec ces deux rameaux qui se sont bien entendu. et les élèves des uns et des autres ont continué.

Fin de l'enregistrement

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Pour citer l'entretien :

« Entretien avec Jacques Livage », par Bernadette Bensaude-Vincent, 12 décembre 2000 Sciences : histoire orale, https://sho.spip.espci.fr/spip.php?article122.

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Entretien avec Jacques Livage, par Bernadette Bensaude-Vincent, 4 janvier 2001

Lieu : Laboratoire de chimie de la matière condensée, Tour 54 (5e étage), Université de Jussieu, Paris, France

Support : non communiqué