Investigation of electrocatalysts by in-situ energy dispersive X-ray absorption and scattering

Cyclic voltammetry, X-ray Absorption Spectroscopy (XANES) and, for the first time, Anomalous Small Angle X-ray Scattering (ASAXS) have been used to study electro-oxidation processes in carbon supported platinum electrocatalysts. The study was performed with synchrotron radiation at the JUSIFA ASAXS beamline, HASYLAB/DESY. The samples were prepared from commercial carbon supported catalyst powder with platinum contents of 5, 10, 60 and 80 wt.%. The powder was mixed with 30 wt.% Teflon and deposited on conductive 0.15 mm thick carbon paper as porous working electrodes for in-situ measurements in a special designed, flat X-ray transparent electrochemical cell. The electrolyte was 1MH2SO4 at room temperature. (orig./DG)