PtRu/C和PtNi/C催化剂合成及其对甲醇氧化的电催化性能

Abstract

PtRu/C and PtNi/C catalysts were prepared by microwave-assistant polyol process,and their microstructure and morphology were characterized by transmission electron microscopy(TEM) and X-ray diffraction(XRD).The results showed that the average diameters of PtRu and PtNi alloy nanoparticles in the catalysts are 2.7 nm and 3.0 nm respectively,and the alloy nanoparticles are homogeneous in size and highly dispersed on the carbon support.Compared with the Pt/C catalyst,the synthesized PtRu/C and PtNi/C catalysts exhibit lower onset oxidation potential and more stable polarization current for methanol electrooxidation.The facts indicate that the PtRu/C and PtNi/C catalysts have more durable electrocatalytic performance for methanol oxidation and better resistance to CO-poisoning than Pt/C catalyst.Because the Ru and Ni metals in the alloys can form oxygen-containing species with their surface adsorbed water under low potential,the adsorbed intermediates such as CO on Pt metal surface can be oxidized to CO2 and the CO-poisoning of the catalysts is avoided.