That requires a long, long answer. I was working in Oxford, back in about 1980, on vanadium(IV) phosphine compounds. We sent in reports to the U.S. Navy, which had funded the work, and about six months later, we got a letter back asking if we could make a salt-potassium hexachloromolybdate(IV), and I said sure. So I went to the library to see how to make these things and I discovered it was pretty well impossible. I’m sitting in the library with all these journals open, every known article on the subject, and I’m getting bored, thinking, "Me and my big mouth," and on the page opposite one of these articles was a paper by Bob Osteryoung on room-temperature molten salts, which is what ionic liquids were then called. And I thought, "That’s a jolly good idea—these would be an ideal environment in which to try and make these compounds." So I wrote a proposal to the U.S. Air Force and three weeks later they flew me out to their laboratories in Colorado. What I didn’t know then was the reason they wanted the compound I was supposedly making was to make batteries in room-temperature molten salts. It was a complex coincidence. John Wilks was also there, and Chuck Hussey from Mississippi was visiting the lab at the same time. And they taught me everything they knew about these room-temperature molten salts: how to make them, purify them, work with them—they were extremely generous. And these were just extremely interesting materials. My one original thought was, "I bet these would be pretty good solvents for doing chemistry with." That was 1981. That’s where everything started.

At that time I was in Oxford. I moved to the University of Sussex to a Lectureship in Experimental Chemistry, as it was called. And it takes a year or two to get up and running. I then sent an application to the Engineering and Physical Sciences Research Council (EPSRC), our equivalent of your NSF. It was a proposal for ionic liquids and catalytic chemistry, and we got a gamma rating. Now, alpha means this is wonderful and if we have the money we will fund you. Alpha-plus means we will definitely fund you. Beta means it has some merit but it may not get funding. Gamma means never darken our doors again; we never want to hear from you, ever. Along with our gamma rating, they sent the referees report. Referee #1 said, "This chemistry is so complicated it will never work." Referee #2 said, "This chemistry is so trivial, it’s not worth doing." Referee #3 said, "Why isn’t he doing the neutron diffraction of vanadium bronzes?", which had no relationship to our proposal. He obviously had the wrong proposal in front of him.

So we were basically rejected as a joke. And the EPSRC is supposed to fund speculative and interesting work. A year and a half later we took the same proposal to British Petroleum, which had a special Venture Research Unit, headed up by Professor Don Braben, who was helped by Dr. David Ray; they looked at the proposal and said this is really exciting. Now, this is industry. You would think they would be hard-nosed, but this Venture Research Unit was also sometimes called the "blue sky research unit". They sent the proposal off to internal review at British Petroleum and we got very strong backing from Professor Mike Green, who was at BP at the time. About a year later, we got a grant for over a quarter of a million pounds. In 1987, that was a massive amount of money. So big it hit the newspapers—The Daily Telegraph—not the science pages, but page five: "BP funds super-solvent." On that grant, I hired Tom Welton, who was doing his DPhil at the time, and that was the start of everything that happened. Without Don Braben’s support, insight, and encouragement, the field of ionic liquids as we now know it, this article (and probably this website) would not have happened.

We then had 10 years of research on ionic liquids in which we published almost nothing, because I thought if I published too quickly all the big American groups would jump in and leave nothing for us. So I let things accumulate, and I only published a few articles that obviously wouldn’t have any industrial applications.

That was part of the thinking but those papers are from the time when we decided to go public. This was all post-1996. In 1999, you see a huge take-off in publications of ionic liquids building on these articles. One of the reasons we’re so highly cited is that these papers are the key markers that people refer back to. Since the 1990s, my philosophy has been it doesn’t matter a damn where we publish. When did I last look at a journal? Maybe 20 years ago. How do you find references? You search on the web. You find something relevant. You download it. In chemistry, the place you publish doesn’t matter. As long as it’s extracted by ISI and as long as it’s hit by search engines, it doesn’t make any difference. The content and quality of the work is what matters, not where you put it.

We published in a Russian journal before that, which came out of a conference, and I never expected it to be seen. They twisted my arm. I went along with them. So this was now the first time I seriously proposed in the West that ionic liquids could be used for green synthesis and green chemistry. We had been doing it for a while, but we hadn’t put out in public that this was a potential application. So once again I was asked to speak at a conference, this time on green chemistry, and that was the journal that was publishing papers from the conference. I had never even heard of it.

It has become unrecognizable. At that time there were less than 20 papers a year being published, and 19 of them were usually on electrochemical applications. It looks like this year alone more than 1,000 papers will be published. That’s almost more in a week than we used to publish in an entire year.

No. The reason we stuck with it from 1981 to 1997 was that we believed in it and we could see the real potential, the value added, the new chemistry, and the green chemistry spin-off. And one of the reasons we sat on things is we knew it would spread like mad once it got out there. People would plunge on it and rip us to pieces.

We stayed ahead.

The secret was industry. After the BP grant, we got another large one from Unilever, and following this we had huge and enthusiastic support from a wide range of industries. We could do more and try out things on a much wider range of subjects than we would ever have dared to do if we were working on our own.

The reality is we were publishing a lot. We just weren’t publishing on ionic liquids. That isn’t my only field. I work in other areas of chemistry, and I work with the British Library and the Oriental Institute in St. Petersburg and the Hermitage on conserving ancient manuscripts. We have done a lot of work in an area called crystal engineering. So it was no problem keeping up our publication rates.

The fact that we had such a body of work accumulated that we didn’t think people could catch up. And meanwhile, America had declared peace on Russia and one of the side-effects of that—a tragedy, really—was that the U.S. Air Force closed its research lab in Colorado. That’s where all the U.S. funding for ionic liquids originated. So the funds dried up in America just at a time that Europe was building up a head of steam on what we’d been doing. Also in 1993, I moved from a readership in Sussex to a chair in Belfast, and I got a very handsome start-up grant, so we were able to increase the effort we could put in. Our group became bigger and by this time we had about eight industrial sponsors. So everything came together. It was a very natural time.

I’ll say something I’ve said before. If you are an industrialist and you have got a process that’s giving you 100 percent yield that is working beautifully, then you don’t need ionic liquids. If you have a problem; if the yield is too low; if the solvent you’re using is going to be banned in two years because it’s too toxic, then ionic liquids are an extremely attractive option for changing a known process or initiating a new one. Chemistry in ionic liquids is totally different than chemistry in the molecular environment of a normal solvent. The kinetics are different. The thermodynamics are different. The outcome is different. Everything is new.

One other thing I’d like to add: one of the reasons we’ve been so successful is the quality of the people we have had come and work with us. It started with Tom Welton, and since then we have had a huge number of wonderful post-docs and graduate students. Martyn Earle has been a godsend. And because this area is so broad, we have had people come from almost every background: inorganic, organic, physical, computational, analytical chemametrics, medicinal, chemical engineering—and that’s just the group working in Belfast. We also founded the Queen’s University Ionic Liquids Laboratories, QUILL, in 1999, co-directed by the invaluable and irreplaceable Prof. Jim Swindall OBE, and there we’re working with 16 industries in a consortium. It’s a wonderful group all working together and making this research possible in what I believe to be a uniquely innovative, exciting, and productive team—industry and academia with common goals and a wealth of broad-based skills to achieve them.

Professor Kenneth R. Seddon
QUILL
School of Chemistry
The Queen's University of Belfast
Belfast, Northern Ireland (UK)