CHARACTERIZATION OF PREPARATION Pt-Ru ALLOY CATALYSTS ON CARBON NANOTUBES BY MICROWAVE POLYOL METHOD.

摘要

The loading amounts and uniform dispersion of catalyst particles are the major bottlenecks in the technical development of methanol fuel cells. In this article, PtRu nanoparticles on purified carbon nanotubes (CNTs)were prepared by microwave polyol method which provided a more homogeneous temperature gradient for the quick nucleation and isotropic loading of PtRu particles on CNTs. The technique has advantages of simplified processes, enhanced adsorption capability, high efficiency of reduction reaction and low-cost operation, compared to those of the processes of physical sputtering and chemical sol-gel method. CNTs were oxidized after HNO3 acidic treatments and purifications to enhance the anchoring and dispersion of metallic nnanoparticles [1-3]. In microwave system, Metal chloride salts can rapidly dissociate and reduce metal catalyst particles, and then deposit on CNTs. However, process temperature, reaction time and additives are important factors that affect the reduction rate of metallic particles from metal chloride salts. The characterization was estimated by XRD, HRTEM, SEM, XPS, ICP-AES, EXAFS.