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J. Phys. Chem. C 2011, 115, 842–845
Autobiography of Alfons Baiker I was born in Zurich, Switzerland, on April 14, 1945 and attended both primary and secondary schools in that city. School, however, was not my main interest, and I did not particularly shine when it came to schoolwork. Instead I spent most of my time with sports and other outdoor activities. It was not easy for my parents to direct my focus to schoolwork, my attention was directed otherwise. My favorite activities were football and handball as well as fishing in the lake of Zurich in summer and ice hockey in winter. After completing primary and secondary school, I began an apprenticeship in mechanics, inspired by my father, who ran a small firm for mechanical engineering. After a very short period of time, however, I felt a strong desire to continue my education, motivated by the fact that my two elder brothers were studying electrical and mechanical engineering, respectively. So, in the evenings and on weekends, I began working toward the general qualification for university entrance (Matura). This double workload lasted four years, because my attempts to give up the apprenticeship and concentrate on my courses were not supported by my father, who insisted that I complete my practical training. In retrospect I can understand his concern. I suffered, not so much because of the double workload, but because I had to give up a lot of my sports activities. I learned to channel my energy to achieve my goals. My enthusiasm for the natural sciences was increasing, and I was driven to learn as much as possible about chemistry and physics; it was soon clear to me that I would go on to study chemistry or physics. I finally decided on chemistry, mainly due to the fact that there were more job opportunities for chemists than for physicists at that time in Switzerland. In order to carry out some experiments before entering the university I set up a small chemical laboratory in my mother’s laundry room. Soon there was no room for her! I found instructions for conducting experiments, sometimes modifying them, with the result that a number of unexpected incidents occurred, much to the displeasure of my parents and brothers. Nonetheless, they let me carry on, which strengthened my resolve to spend every free minute in the laundry room with my experiments. After successfully completing my four-year apprenticeship as a mechanic and, in the same year, passing my preparatory course for university entrance (Matura), I began my longed-for study of chemistry at the ETH Zurich. My time at the ETH proved to be an exceptional enrichment in every sense of the word. At the end of the fourth semester of chemistry it was time to decide on a major: chemistry or chemical engineering. I chose the latter. After the successful completion of my undergraduate course I began my doctoral work in the former Laboratory for Technical Chemistry (ETH Zurich) under the guidance of Professor Werner Richarz. He succeeded in convincing me to focus on nonstationary operated catalytic fixedbed reactors. The goal of my doctoral thesis was to determine whether the efficiency of a fixed-bed reactor could be increased by forced periodic variation in the process parameters (e.g., concentration and pressure). I was particularly interested in the interplay between chemical reaction and mass and heat transfer and its impact on global reaction kinetics. The topic was also attractive, because I was able to apply my mechanical skills in constructing the experimental setup for such investigations. After I had convinced my advisor to buy one of the first midrange process computers in our institute, a PDP-11, I constructed a fully automated system that allowed me to collect a tremendous amount of data, so that I could accomplish my doctoral thesis in relatively short time, less than three years. During my doctoral studies I realized that at that time, reaction engineering tended to be limited to describing macroscopic phenomena, clearly important for designing reactors but at the expense of gaining insight into molecular processes on the surface of the catalyst. A main focus of chemical engineering was the modeling of macroscopic processes, without making a real attempt to gain an understanding of those processes on the molecular level. Even though I was convinced of the importance of modeling in chemical reaction engineering, I found this approach unsatisfactory and was drawn increasingly to physical chemistry, which was more concerned with a fundamental understanding of molecular processes. After earning my doctorate from the ETH I received a number of interesting job offers in the Swiss chemical industry, many through my doctoral adviser, Werner Richarz, who had excellent contact with many firms. In the end, however, I decided against a career in industry, fearing that I would no longer be able to indulge my passion for research. At the same time I was becoming more interested in heterogeneous catalysis and related surface processes. Several colleagues encouraged me to follow a career in academia. So my course was set. At that time, chemistry at Swiss universities was dominated by the requirements of the pharmaceutical industry; only very little research was devoted to heterogeneous catalysis and surface chemistry. 10.1021/jp1079873 2011 American Chemical Society Published on Web 01/27/2011
J. Phys. Chem. C, Vol. 115, No. 4, 2011 843 My doctoral adviser suggested, therefore, that I go abroad for a period of postdoctoral study. Stipends from the International Research Worker Interschemes and the Swiss National Science Foundation (SNF) made it possible for me to gain firsthand experience of catalysis research at a number of European universities, followed by an extended period in the research group of Michel Boudart at Stanford University in California. My time at Stanford was an eye-opener in the true sense of the word. I was fortunate to be there at the height of Boudart’s career, and I could not have wished for a better postdoctoral position. It was at Stanford that I realized how important a molecular understanding is for the further development of catalysis, and I began to delve into the chemistry and physics of surfaces. Michel’s lecture on kinetics was one of the best I had ever attended and made a lasting impression on me. A blackboard and a piece of chalk were all he needed to hold the attention of his audience. Quite a challenge for me, however, when he asked me to take over his lecture for a while. I also began to work on my postdoctoral lecture qualification (Habilitation) in the field of the kinetics of structure sensitive reactions and learned a great deal from the excellent work being carried out in Boudart’s group on the structure sensitivity of ammonia synthesis. During my stay in California I married my girlfriend of many years, Doris Blaser, who had accompanied me to Palo Alto. Even though there were a number of possibilities for me to pursue a career in the United States, I decided to return to Switzerland for family reasons. Back at the ETH Zurich in 1980, I submitted my Habilitation and soon started to build up my own research group in the former Laboratory for Technical Chemistry. Most of my first research projects were financed by Swiss industry. This phase was characterized by intensive collaboration with Alexander Wokaun, who, at the time, held a professorship in physical chemistry at the University of Bayreuth in Germany; several years later he moved to the Paul Scherrer Institute in Switzerland. He spurred my interest in in situ spectroscopy and its application in catalysis. We had several joint projects on the characterization of new catalytic materials developed in our laboratory, such as metallic glasses, xero- and aerogels, inorganic-organic hybrid-gels, and grafted monolayer-type materials. For the research on metallic glasses I received generous support from Lonza AG, whose special interest was the catalytic production of chemical intermediates for fine chemistry. The company was interested in the exploration of the catalytic potential of these novel materials. An interesting fundamental question, which we tried to resolve, was how disordered materials, without long-range ordering of the constituents, would behave in catalysis and the type of structural changes these metastable materials would undergo when exposed to conditions where catalysis occurs. During this early period I received various tempting offers for professorships at universities in The Netherlands, Germany, and the United States, all of which I decided to turn down so that our family could remain in Switzerland. Not only was my research group growing, but our family too: Marc was born in 1980, Jan in 1982, and Nicolas in 1987. In retrospect I realize that my decision to turn down these positions was not without risks. I could not count on the creation of a chair in catalysis at the ETH Zurich, and promotions within the ETH were frowned upon. In the end, though, those offers helped me to become established at the ETH. Forest decline was a new topic, and the awareness that heterogeneous catalysis could contribute to the protection of the environment was growing in Switzerland too. This, as well as the growing interest in heterogeneous catalytic processes in industry, certainly played a role in the creation of two chairs in heterogeneous catalysis in the Laboratory for Technical Chemistry at the ETH, one occupied by Roel Prins, and the other by me. Thus, the prerequisites for successful research in heterogeneous catalysis at the ETH were met, all the more since Roel and I focused on different but complementary aspects of catalysis. By the end of the 1980s my group had more than 25 members, and as well as the support from the Swiss National Science Foundation and the ETH, we continued to receive substantial financial support from Swiss and foreign chemical industries. The main goal of our research remained the advancement of the scientific principles of the design of efficient heterogeneous catalytic processes, based on the optimal usage of energy and raw materials. Excellent scientific co-workers joined my group: Rene´ Ko¨ppel, Marek Maciejewski, and, somewhat later, Tamas Mallat. Rene´ was a former doctoral student, who returned to our group after a postdoctoral stay in Sydney, Australia. Marek joined us from the University of Warsawa, Poland, and Tamas from the University of Budapest, Hungary. They greatly increased the working power of our group and jointly with some highly motivated doctoral students, we were able to conduct research in many interesting areas such as the selective reduction of NOx, catalysts for hybrid motors, amination of alcohols, aerobic oxidation in fine chemistry, catalytic syntheses based on carbon dioxide, metallic glasses as catalysts, and epoxidation of olefins with Ti-Si aerogels, just to mention a few. At the same time we began our work on asymmetric hydrogenation in a joint project with Hans-Ulrich Blaser of former Ciba-Geigy, triggering my long-lasting interest in asymmetric catalysis and chiral surfaces. During the 1990s we concentrated on four main areas of research: novel catalyst materials, reactions in supercritical fluids, catalytic synthesis of fine chemicals, and environmental catalysis. The research on supercritical fluids and their use in chemical reactions was mainly initiated
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J. Phys. Chem. C, Vol. 115, No. 4, 2011 by our long-lasting cooperation with former Hofmann-La Roche AG which played a pioneering role in the application of supercritical media in chemical reaction engineering. When Thomas Bu¨rgi and Jan-Dierk Grunwaldt joined our group to work on their Habilitation, we extended our work in in situ spectroscopy and molecular modeling, which are still an important part of our current research activities. Thomas and Jan-Dierk have both made invaluable contributions to the development of in situ spectroscopy in our group. Thomas was responsible for setting up in situ ATR-IR spectroscopy and modulation excitation spectroscopy and Jan-Dierk in situ X-ray absorption spectroscopy. Both worked with a group of highly motivated doctoral students, two of whom, Davide Ferri and Atsushi Urakawa, remained in our group as senior scientists and were responsible for extending our research activity in in situ spectroscopy to the application of modulation excitation spectroscopy, polarization modulation infrared reflection-absorption spectroscopy, and time- and space-resolved infrared spectroscopy. In situ spectroscopy is still a flourishing part of our current research. Thomas and somewhat later Jan-Dierk left our group for professorships at the University of Neuchaˆtel in Switzerland, and the Technical University of Denmark in Kopenhagen, respectively. At about the same time as our in depth in situ spectroscopic studies, we also increased our activities in molecular modeling. I was somewhat skeptical at first, because when dealing with complex systems of large molecules adsorbed on a surface, one quickly encounters several limiting factors of the theoretical approach. Nevertheless, since the early 1990s we have had a small group focusing on the use of theoretical chemistry to support our experimental research. The leader of this group was Angelo Vargas, who upon completion of his doctorate, remained with us for several years as a senior researcher. Today it is impossible to imagine research in catalysis without the support of a growing arsenal of theoretical methods. In the field of asymmetric hydrogenation, for example, modeling is an important aid. We often reached our limit as far as experimental methods were concerned and had to rely on theoretical methods to achieve greater insight. In chiral catalysis, important information obtained through theoretical calculations, was later confirmed by in situ spectroscopy. In the past decade the most prominent research activities in our group have been: catalytic reactions in supercritical media, chiral catalysis, in situ spectroscopy, CO2 utilization, nitrogen storage-reduction catalysis, aerobic oxidation in fine chemistry, and flame synthesis of catalytic materials. Even though we had worked on some of these topics for a number of years before, the last 10 years brought new momentum, especially in in situ spectroscopy, through the development of different high-pressure cells, which enable the observation of reactions under high pressure in supercritical media. More recently, we have been concentrating on the potential of catalytic systems, which combine ionic liquids and supercritical CO2. They offer fascinating possibilities for future research and applications. Our interest in the flame synthesis of new catalytic materials came about through our collaboration with the group of Sotiris Pratsinis at the ETH Zurich. With a number of doctoral students we explored the potential of flame synthesis for the production of catalytic materials. A series of materials with exceptional structures and catalytic characteristics resulted from this ongoing cooperation. In the process of putting these reminiscences on paper I have covered about 40 years of my work in science. It is amazing to look back on the developments made in catalysis research in this time. The principle goal of catalysis research is of course still the same, namely the development of environmentally benign chemical processes, making optimal use of raw materials and energy. However, great advances have been made in the development of experimental and theoretical tools, which are important aids in attaining this goal. I have witnessed tremendous progress in many areas of catalysis research and was privileged to play a part in some of these developments. I have always appreciated the multidisciplinary aspects of catalysis research, and the ultimate goal, the integration of the basic findings in an efficient process to meet the requirements of green chemistry, has made my job an extremely rewarding and satisfying one. ETH is a superb place for pursuing and achieving this goal. I was privileged to have excellent co-workers throughout my career, and I am most grateful for their scientific contributions as well as the highly stimulating and pleasant working atmosphere they helped to create. I am proud that many of them have gone on to follow productive careers in industry or academia, and I am particular grateful to my former senior scientists, Tamas Mallat and Marek Maciejewski, who made many valuable contributions to the broad spectrum of our research activities and worked with me for a long period of my scientific career. I also wish to thank all scientific collaborators and friends, who have enriched my life, both in science and on a personal level. Many of their names appear in my list of publications. Our achievements would not have been possible without the skilled and dedicated people in the mechanical and electronic workshops of our institute; I give them my heartfelt thanks for their skilled and valuable support. It is a great pleasure to see the many excellent contributions compiled in this special issue of The Journal of Physical Chemistry dedicated to me. I thank all my friends and colleagues throughout the scientific community who contributed and made this a most memorable honor for me.
J. Phys. Chem. C, Vol. 115, No. 4, 2011 845 Finally, special thanks go to my wife, Doris, for her love and companionship, and to our sons, Marc, Jan, and Nicolas, for their patience with a father, who was often preoccupied with his much-loved science.
Alfons Baiker JP1079873
