Development of new systems of nano-disperse Pt-(2%Pt-Ce0.9W0.1O2)/C electrocatalysts tolerant to carbon monoxide (CO) for PEMFC anodes

The nanophase material (powder) of Ce0.9W0.1O2 was synthesized via coprecipitation of oxalates of cerium (IV) and tungsten cations. Pt-Ce0.9W0.1O2 (2 wt% Pt) was prepared by an alcohol-reduction process using H2PtCl6.6H2O as source of Pt, Ce0.9W0.1O2 as support and ethylene glycol as solvent and reducing agent. Pt-Ce0.9W0.1O2 was physically mixed with commercial Pt/C E-TEK (20 w% Pt) to produce the Pt-(2%Pt-Ce0.9W0.1O2)/C electrocatalyst. The prepared electrocatalysts were characterized by energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and CO stripping. The performances of Pt/C E-TEK and Pt-(2%Pt-Ce0.9W0.1O2)/C electrocatalysts were tested in single fuel cell fed with a mixture H2/CO (100 ppm of CO). The results showed that the mixture of 2%Pt-Ce0.9W0.1O2 and Pt/C E-TEK increases the CO tolerance in a single fuel cell operating at 85 ºC compared with Pt/C E-TEK.