Pt-Mo/C, Pt-Fe/C, and Pt-Mo-Sn/C Nanocatalysts Derived from Cluster Compounds for Proton Exchange Membrane Fuel Cells

Abstract

Nanosized bimetallic PtMo, PtFe and trimetallic PtMoSn catalysts deposited on highly dispersed carbon black Vulcan XC-72 were synthesized from the cluster complex compounds PtCl(P(C6 H5)3)(C3 H2 N2 (CH3)2)Mo(C5 H4 CH3)(CO)3, Pt(P(C6 H5)3)(C3 N2 H2 (CH3)2)Fe(CO)3 (COC6 H5 C2 C6 H5), and PtCl(P(C6 H5)3)(C3 N2 H2 (CH3)2)C5 H4 CH3 Mo(CO)3 SnCl2, respectively. Structural characteristics of these catalysts were studied using X-ray diffraction (XRD), microprobe energy dispersive spectroscopy (EDX), and transmission electron microscopy (TEM). The synthesized catalysts were tested in aqueous 0.5 M H2 SO4 in a three-electrode electrochemical cells and in single fuel cells. Electrocatalytic activity of PtMo/C and PtFe/C in the oxygen reduction reaction (ORR) and the activity of PtMoSn/C in electrochemical oxidation of ethanol were evaluated. It was shown that specific characteristics of the synthesized catalysts are 1.5–2 times higher than those of a commercial Pt(20%)/C catalyst. The results of experiments indicate that PtFe/C, PtMo/C, and PtMoSn/C catalysts prepared from the corresponding complex precursors can be regarded as promising candidates for application in fuel cells due to their high specific activity.