I-11 – Functional metal oxide interfaces in efficient electrochemical energy conversion, biomass conversion and charge storage systems


Organizers: Pawel Kulesza (University of Warsaw), Nicolas Alonso-Vante (Université de Poitiers), R. John Errington (Newcastle University).

Sebastian Fiechter

Institut für Solare Brennstoffe (EE-I-F), Helmholtz-Zentrum Berlin, Germany

I studied materials science at the Crystallographic Institute of the Albert-Ludwig-University Freiburg im Breisgau (Germany) from 1973-1978. In my PhD work I investigated the growth mechanisms of semiconducting copper ion conductors Cu6PS5Hal (Hal = Cl, Br, I). Work on the photo-intercalation of copper in the material brought me into contact with Professor Helmut Tributsch from the former Hahn-Meitner-Institute Berlin (HMI), where I accepted a job offer in 1983. Main topic of my research activities concerns the development of new materials for energy converting devices such as solar cells, fuel cells and photoelectrochemical devices for water splitting. Elucidating the structure - function relationship the influence of the crystal structure, its defect chemistry and the morphology of the prepared materials (crystals, powders and layers) on the optoelectronic and catalytic properties is in the focus of my interest. In the last decade I concentrated on the preparation of catalysts for fuel cells and water splitting devices. Papers were published in my group on the function of carbon supported selenium-modified ruthenium catalysts and later on porphyrin-based oxygen reduction catalysts, where catalytically active Fe-N-C and Co-N-C centres are embedded in graphene nano-sheets. In-operando and in-line studies were performed on RuSex, Co-Fe-N as well as on CoOx and MnOx electrocatalysts using X-ray absorption (in-situ EXAFS, XANES) and synchrotron radiation X-ray photoelectron spectroscopy (in-line SR- XPS). As photocatalytically active electrodes, such as structured films of α-Fe2O3 and Fe2WO6, were investigated as water oxidizing anodes using sol gel and magnetron sputtering as deposition techniques. A water splitting devices based on a 3j a-Si-µc-Si superstrate solar cell with MoSx and MnOx as alternative catalysts on front and back contact has been demonstrated recently.