To some extent, the behaviors of catalysts have great affection on the performance of the fuel cells. The application of Pt alloy can not only reduce consumption of Pt loaded on the catalyst layer, but also often raise catalyst performance simultaneously. Certain Pt-Cr alloys were synthesized with different atom ratio using co-precipitation and chemical reduction in aqueous phase, while high resolution transmission electron microscope (HRTEM) and scanning electron microscope (SEM) were used to assess the physical properties of these alloys. From the results, the PtCr alloy could be observed to be uniformly deposited on the carbons and the diameters of alloy particles were less than 4 nm. Cyclic voltammetry was used to view the catalytic abilities of these alloys. The best atom ratio of alloy was Pt/Cr＝2/1 because it exhibited the best catalytic ability to the oxygen reduction reaction in our experiment conditions.

Key words: proton exchange membrane fuel cell, synthesis, alloy, electrochemical, catalysis