Abstract
The oxygen reduction reaction in sulphuric acid on commercial carbon supported platinum and ruthenium catalysts as well as on a home-made carbon supported ruthenium selenide catalysts (RuSe x /C) was investigated. The RuSe x /C catalysts were synthesised using similar procedures to those found in the literature. A dependency of H2O2 formation on the selenium content was found using the thin-film rotating ring disc electrode technique, namely that the H2O2 formation in the typical operation range of a Direct Methanol Fuel Cell (0.7-0.4 V) on Pt/C is below 1% and 1-4% on Ru/C and RuSe x /C catalysts. Finally for comparing the intrinsic activities of the catalysts the electrochemically active surface areas were determined in-situ by means of copper underpotential deposition. Our results indicate a comparable activity of the present RuSe x /C catalyst to commercial Pt/C if the activities are related to the electrochemical active areas.