Michael Grätzel
Michael Grätzel (born 11 May 1944, in Dorfchemnitz, Saxony, Germany) is a professor at the École Polytechnique Fédérale de Lausanne where he directs the Laboratory of Photonics and Interfaces. He pioneered research on energy and electron transfer reactions in mesoscopic-materials and their optoelectronic applications. He co-invented with Brian O'Regan the Grätzel cell in 1988. Author of over 1000 publications, two books and inventor or co-inventor of over 80 patents, he has been the Mary Upton Visiting Professor at Cornell University and a distinguished visiting professor at the National University of Singapore, and is currently a  distinguished scientist at King Abdulaziz University. He was an invited professor at the University of California, Berkeley, the École normale supérieure Paris-Saclay and Delft University of Technology. Career. In 1968 he graduated from Free University of Berlin, in 1971 he earned the Doctor of Philosophy in natural science in Technical University of Berlin. In 1976 he earned Doctor of Science in physical chemistry. Since 1977 to the present day he is a professor at the Swiss Federal Institute of Technology in Lausanne, where he directs the Laboratory of Photonics and Interfaces. He acted as postdoctoral research fellow, lecturer, visiting  professor in Berlin Institute for Nuclear Researches named after Hahn and Meitner, Free University of Berlin, University of California at Berkeley, Ecole Normale Supérieure de Cachan (Paris), Oil and Gas Research Fund, University Notre Dame (US) and other educational and research centers. In 1991 he published his breakthrough work in Nature magazine with regard to the new type of solar cells based on a three-dimensional array of tiny (mesoscopic) oxide semiconductor particles with wide band gap covered with an organic pigment that have brought the name of professor into repute and were named as Graetzel cells. Graetzel is the  holder of 10 honorary doctorates in Universities of Asia and Europe: Denmark, Holland, China, Sweden, Singapore and other countries. He is the laureate of tens of prestigious scientific and engineering prizes, such as Grand Prix “Millennium Technology”, Medal of Faraday granted by British Royal Society, Gutenberg Prize, Albert Einstein Prize and others. Graetzel is the member of Swiss Chemical Society, Society of Max Plank, and German Academy of Science (Leopoldina), as well as an honorable member of the Israeli Chemical Society and the Bulgarian Academy of Science, an honorary fellow of the Royal Society of Chemistry, and a Fellow of  the US-National Academy of Inventors. Scientific achievements. Michael Graetzel is one of developers of the so-called Graetzel cell operating on the principles of photosynthesis– the process similar to biochemical one and used by plants for light energy conversion into carbohydrates. The invention developed by the scientist since 1970th of past century represents profitable alternative for expensive and sophisticated technologies of photovoltaic arrays produced on the basis of silicon (in particular, the latter require expensive silicon of high purity). Compared to silicon-based batteries the Graetzel cells are rather simple and manufactured of low cost materials. First Graetzel cells  discovered in 1991 were based upon porous layer of nanoparticles of titanium oxide covered with organic dye. Electrons from organic dye, able to efficiently adsorb solar radiation, migrate into conductive electrode made of titan dioxide and generate the electric flux. Commercial manufacturing of such cells was started just in 2009. At the initial stage, they possessed poor efficiency performances of 3–8% and poor stability due to available unstable liquid electrolyte and organic dye inside the cells. By 2012, the efficiency of cells has been increased by 11.9%. For the period over 20 years, the researchers headed by Graetzel have been  working on the increase of efficiency of Graetzel solar cells and simplification of the technology of their production. In 2009, Japanese scientists managed to make a breakthrough and transfer from an organic pigment in the cells to hybrid organic-inorganic perovskite materials, and in 2012, they managed to replace liquid electrolyte by solid organic semiconductor. At that, a new class of devices, the so-called "perovskite solar cells" has emerged. At present, these devices are considered the most intensively studied materials in the world, and their efficiency currently exceeds 22%. Michael Graetzel's laboratories has set several world records with  respect to the efficiency of perovskite solar batteries. Michael Graetzel is an ultimate leader in the field of materials for solar power industry and continues his works on development of photovoltaics all over the world; in particular, he actively cooperates with the researchers from Lomonosov Moscow State University in the area of perovskite photovoltaics. Recognition. His work has been cited over 250,000 times, his h-index is 224, making him one of the 10 most highly cited chemists in the world. He was a frequent guest scientist at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, was a fellow  of the Japanese Society for the Promotion of Science. In 2009 he was named Distinguished Honorary Professor by the Chinese Academy of Science (Changchun) and the Huazhong University of Science and Technology. He has received numerous awards including the Millennium 2000 European innovation prize, the 2001 Faraday Medal of the British Royal Society, the 2001 Dutch Havinga Award, the 2004 Italgas Prize, two McKinsey Venture awards in 1998 and 2002 and the 2005 Gerischer Prize. In 2007 he was awarded the Harvey Prize of Technion for pioneered research on energy and electron transfer reactions in mesoscopic-materials and their optoelectronic  applications. In 2009 he was awarded the Balzan Prize for the Science of New Materials. On 9 June 2010, Grätzel received the Millennium Technology Prize, for development of dye-sensitized solar cells. The cash prize, worth 800,000 euros, was awarded, in Helsinki, Finland, by the president of Finland, Tarja Halonen. His most recent awards include: 2011 Gutenberg Research Award; 2011 Paul Karrer Gold Medal; 2011 Wilhelm Exner Medal; 2012 Albert Einstein World Award of Science; and the 2013 Marcel Benoist Prize. In 2015 he received the King Faisal International Prize in Chemistry and in 2017 the Global Energy Prize "for  transcendent merits in development of low cost and efficient solar cells, known as “Graetzel cells”, aimed to creation of cost-efficient, large-scale engineering solutions for power generation." In 2020 he received the BBVA Foundation Frontiers of Knowledge Award. He holds a doctorate from the Technical University of Berlin and honorary doctorates from Faculty of Science and Technology at Uppsala University, Sweden (1996), Turin and Nova Gorica. He was elected honorary member of the Société Vaudoise des Sciences Naturelles. Dr. Grätzel is a member of the scientific advisory committee at the IMDEA Nanoscience Institute. Interesting facts. Graetzel cell-based batteries  are more convenient for consumer compared to silicon-based photocells – they could be made flexible and in various colors. It is convenient for use and power generation, for instance, in various structural elements of buildings. It is possible to create structurally transparent cells able to generate electric power within various bands of light frequencies, up to infrared one. It means that, in particular, they could be embedded into window glasses resulting in double effect for premises cooling and associated electric power generation. Several companies have already launched mass production of photocells based upon renewed Graetzel cells. Dr. Graetzel is the  author of more than 1300 publications, two monographs; he holds more than 50 patents. He is one of the three globally most cited chemistry academicians.