| The shape-controlled preparation of electrocatalysts for direct methanol fuel cells (DMFC) was investigated with three different methods in this work. The main factors affecting the preparation, identification of protective agents and their concentration, precursors, pH value of the solution, assistant reagents and temperature, etc., were systematically examined and optimized in order to control the process of the preparation. With combination of the polymer-protective method and modified polyol process, the platinum particles with a majority of tetrahedral shape were synthesized successfully in which the ratio of Pt(111) facets to all Pt(hkl) facets was increased significantly.Using SBA-15 and MCM-41 as templates, the Pt and PtRu electrocatalysts with the shapes of nanowires and/or nanorods were synthesized by template-assisted method. The results of TEM, XRD characterization and conventional electrochemical tests demonstrated that the PtRu electrocatalyst prepared by SBA-15 template shows a higher alloy contents, bigger aspect ratio and better performance than that of by MCM-41 template.The Pt-based electrocatalysts prepared with ethylene glycol method show a better dispersion and relatively higher electrocatalytic performance compared to those commercial counterpart. The species and their valence on the surfaces of the electrocatalysts were analyzed by means of HRTEM,XRD,XPS measurements, Ru oxides or hydrous Ru oxides on the surface of home-made electrocatalyst were detected and those oxides may result in a higher performance compared with the commercial counterpart.The effects of polymer-protective agents on the process of particle growth were examined and the possible mechanism about it was also discussed .
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