DFG Research Training Group "Chemical Photocatalysis" (GRK 1626, Associated Member)

The research training group GRK 1626 develops selective chemical photocatalysts for endothermic or kinetically hindered organic reactions and describes the key parameters of their design and function. This will pave the way to a broader use of solar energy for chemical transformations. Our only sustainable energy source on earth is solar irradiation. Photovoltaic cells, converting solar energy into electrical energy, have already been developed to broad commercial application. The use of visible light energy to accelerate or power chemical reactions has received much less attention, although early pioneers such as Giacomo Ciamician have demonstrated the principles more than 100 years ago. However, the processes connecting photophysical excitation of chromophores with catalytic conversion of substrates are complex and not well understood on the molecular level. Spectroscopy of molecules, catalysis and classical photochemistry are well developed areas in chemistry. In their combination they enable innovative and new solutions contributing to a more sustainable development. The research training group "Chemical Photocatalysis" brings together the complementary expertise from the different areas to jointly work on selected photocatalytic reactions. The main challenge is the kinetic, geometrical and energetic coordination of the physical and chemical steps to achieve efficient photocatalysis. Although photoinduced electron transfer processes have been deeply investigated, the utilization of charge separated intermediates in chemical reactions has not been widely explored and is still difficult to design and predict. Our interdisciplinary research effort shall contribute to the future development of this promising area. The scope of potential applications of chemical photocatalysts is wide ranging from enantioselective catalysis in synthesis over chemical storage of energy to analytic applications.