A high-performance Mo2C-ZrO2 anode catalyst for intermediate-temperature fuel cells

Anode performance of non-Pt catalysts for hydrogen oxidation was investigated in intermediate-temperature proton exchange membrane fuel cells. Molybdenum carbide (Mo2C) showed the highest catalytic activity among the transition metal carbides tested. Furthermore, the catalytic activity of Mo2C was significantly improved by the addition of ZrO2 to the anode. Transmission electron microscopy and X-ray diffraction measurements revealed that Mo2C was more highly dispersed in the Mo2C-ZrO2/C than in the Mo2C/C, suggesting that the particle growth of Mo2C was suppressed by the addition of ZrO2. We also tested the performance of a fuel cell using Mo2C-ZrO2/C and Sn0.9In0.1P2O7 as the anode and electrolyte materials, respectively, between 150 and 300 degrees C. At 250 degrees C or higher, the Mo2C-ZrO2/C anode showed a cell performance comparable to that of the Pt/Canode. However, cell performance was strongly dependent on the operating temperature, reflecting that the catalytic activity of Mo2C-ZrO2 was greatly lowered by the decrease in operating temperature. Thus it was concluded that the Mo2C-ZrO2 catalyst is a promising alternative anode material to Pt, especially at intermediate temperatures. (c) 2006 The Electrochemical Society.