Electrolysis of Ethanol and Methanol at PtRu@Pt Catalysts

Abstract

Electrolysis of ethanol in a proton exchange membrane (PEM) cell is an attractive method for generating hydrogen from renewable resources. However, the most active anode catalysts, such as PtRu, produce acetic acid as the main product, which makes the process very inefficient. Core–shell nanoparticles can improve efficiency by providing more selective cleavage of the C–C bond at a Pt shell. Here, the influence of the amount of Pt deposited onto a commercial PtRu/C catalyst has been investigated for electrochemical oxidation of ethanol and methanol, in aqueous H2SO4 at ambient temperature and in a PEM electrolysis cell at 80 °C. It is shown that addition of a Pt shell improves voltammetric activity markedly for both methanol and ethanol oxidation, while half-wave potentials in the PEM cell are shifted to higher potentials as the Pt coverage is increased. However, limiting currents for ethanol oxidation in the PEM cell are increased, and it is shown that the distribution of products shifts strongly towards CO2, which provides more efficient production of hydrogen.