Mixed Metal Oxides as Corrosion-Resistant Catalyst Supports for Polymer Electrolyte Fuel Cells

Metal oxides RuO2-SiO2, and Mo and Ta doped TiO2 were studied as possible non-carbon electrocatalyst supports for polymer electrolyte fuel cells (PEFCs). RuO2-SiO2 mixed metal oxides offered the best combination of BET surface area, electron conductivity and support stability among the supports studied. RuO2-SiO2 (0.5:0.5) showed high BET surface area of ~290 m2g-1 and high electron conductivity of ~5 Scm-1. It also possessed outstanding support stability and comparable catalyst stability when compared to state-of-the-art Pt/C electrocatalyst. Under fuel cell operating conditions of 80 {degree sign}C and 75% RH, the RuO2-SiO2 (0.5:0.5) electrocatalyst yielded mass and area specific activities of 50 mAmgPt-1 and 156 µAcm-2 respectively at 0.9 V vs RHE.