Research at the Laboratory of Photonics and Interfaces EPFL Graetzel group (LPI)
The main focus of research at LPI is on photosystems that generate electric power or fuels from sunlight. The inverse process of producing light from electricity in organic light emitting diodes (OLEDS) and the storage of electricity in batteries is also being investigated. The majority of devices examined at LPI employs mesoscopic structures with nanometer-sized features as a key substrate element. In fact, it was the Grätzel group at LPI that pioneered the use of such mesoscopic architectures for the solar production of electricity and fuels. The choice of mesoscopic oxides is supported by our extensive studies of photoinduced electron- and energy-transfer processes of nanocrystalline systems of various kinds. The advantages of using mesoscopic photosystems as solar light harvesters are manifold. Advances in our understanding on how to control/manipulate interfacial charge transfer enables to design efficient photochemical systems that effect overall conversion of solar energy to electric power, as in solar cells or solar fuels, such as H2 from photoelectrochemical water splitting and reduction of CO2 to CO or even C2 products including C2H4 and C2H5OH. Currently, LPI pursues active research in the following three key areas: (1) dye-sensitized solar cells, (2) hybrid perovskites, and (3) solar fuels.