Ruthenium selenide catalysts for cathodic oxygen reduction in direct methanol fuel cells
- 292 Downloads
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.
KeywordsOxygen reduction Rotating ring disc electrode Copper underpotential deposition Ruthenium Selenium
We thank the BMBF for financial support under contract 01SF0302 (“O2RedNet”) and the “Gemeinschaftslabor für Elektronenmikroskopie” (Prof. J. Mayer, RWTH Aachen) for use of their TECNAI G2 F20 microscope to perform the HAADF-STEM and EDX measurements. We also thank Dr Rainer Bußar for helpful discussions.