Carbon-Nb0.07Ti0.93O2 composite supported Pt-Pd electrocatalysts for PEM fuel cell oxygen reduction reaction

Carbon-Nb0.07Ti0.93O2 (C-67 (wt%)-(Nb0.07Ti0.93O2)(33) (wt%)) composite support for Pt0.55Pd0.45 alloy catalysts was prepared by hydrolysis of metal alkoxides in the presence of carbon. Physical characterization by XRD. EDX, BET. TEM and TGA showed that the Nb0.07Ti0.93O2 was well distributed on the carbon particle surface with an average particle size of 15 nm. and this support has a high surface area of 176 m(2)/g and a similar porosity to that of carbon used to prepare this composite support. Pt0.55Pd0.45 alloy nanoparticles were deposited on the composite support to form a Pt0.55Pd0.45/C-67 (wt%)-(Nb0.07Ti0.93O2)(33) (wt%) catalyst, which shows a higher catalytic activity toward ORR than those of monometallic counterpart Pt/C-67 (wt%)-(Nb0.07Ti0.93O2)(33) (wt%), Pt0.55Pd0.45/C, and Pt0.55Pd0.45/Nb0.07Ti0.93O2. Pt0.55Pd0.45/C-67 (wt%)-(Nb0.07Ti0.93O2)(33) (wt%) showed higher stability than Pt0.55Pd0.45/C, and similar to the commercially available Pt/C catalyst. (C) 2012 Published by Elsevier Ltd.