[Zurück]

Ch. Rameshan, A.K. Opitz, A. Nenning, M. Kubicek, N. Barrabés-Rabanal, T. Götsch, R. Rameshan, R. Blume, M. Hävecker, A. Knop-Gericke, B. Klötzer, J. Fleig, G. Rupprechter:
"Enhancing Catalytic Activity by Electrochemically driven Metal Nanoparticle Exsolution - Water and C0₂ Electrolysis";
Poster: OperandoVI - 6th International Congress on Operando Spectroscopy, Estepona, Malaga; 15.04.2018 - 19.04.2018; in: "OperandoVI - 6th International Congress on Operando Spectroscopy", (2018), S. 72.

In heterogeneous catalysis surfaces decorated with uniformly dispersed, catalytically highly active particles are a key requirement for excellent performance. One of the main tasks in catalysis research is the continuous improvement or development of catalytically active materials.
An emerging concept in catalyst design is to selectively and reversibly tune and modify the surface chemistry by electrochemical polarisation. Perovskite-type catalysts raise the opportunity to incorporate guest elements as dopants. Upon electrochemical polarisation these dopants emerge from the oxide lattice to form catalytically active clusters or nanoparticles on the surface (by exsolution). In consequence this leads to a strong modification or enhancement of catalytic selectivity and activity. Electrochemical polarisation offers the possibility to adjust the surface chemistry in response to an external signal in real time (here by the applied voltage).
We present studies for high temperature water splitting and C02 electrolysis in a realistic catalytic reaction environment (operando), on different acceptor doped perovskite-type electrodes, and show a direct correlation of surface chemistry with catalytic activity, selectivity and the electrochemical stimulation. This is achieved by a unique combination of surface science, heterogeneous catalysis and electrochemistry.

ln-situ XPS, Perovskite, Exsolution, Nanoparticles