RESUMO
We report a new synthesis of PtRe alloy nanoparticles (NPs) and their electrocatalytic activity for methanol oxidation. PtRe alloy NPs with controlled composition were prepared by a capping agents-based colloidal method. In the synthesis, trioctylamine was used as high-boiling solvent, and oleylamine/oleic acid were employed as capping agents to control the particle size and dispersion. The PtRe NPs were fully characterized by TEM, EDX, XRD and XPS. The as-prepared PtRe NPs had a narrow size distribution, and displayed a good dispersion in hydrocarbon solvents. Carbon-supported PtRe catalysts were prepared by physical deposition of as-prepared particles on carbon powder, followed by the catalytic activation at 400 degrees C in Ar/H2. Electrochemical studies showed the PtRe catalysts had high activity for methanol electrooxidation.
RESUMO
PtMo alloy and MoO(x)@Pt core-shell nanoparticles (NPs) were successfully synthesized by a chemical coreduction and sequential chemical reduction method, respectively. Both the carbon-supported alloy and core-shell NPs show substantially higher CO tolerance, compared to the commercialized E-TEK PtRu alloy and Pt catalyst. These novel nanocatalysts can be potentially used as highly CO-tolerant anode electrocatalysts in proton exchange membrane fuel cells.