Journal of Inorganic Materials (无机材料学报) 2014/29:7 PP.722-728
The Pd/PMo12-GN composite film was prepared by electrochemical reduction, in which GN prepared from GO reduction under UV irradiation and simultaneously functional embellished by PMo12. The as-prepared composite was characterized by X-ray diffraction, X-ray photoelectron spectroscope, scanning electron microscope and transmission electron microscope. It was shown that Pd/PMo12-GN composite was successfully prepared and Pd particles were uniformly-dispersed with a small particle size on the PMo12-GN substrate. Cyclic voltammetry, chronoamperometric curves, CO-stripping curves and EIS were used to discuss the electrocatalytic activities of the Pd/PMo12-GN composite film. The results indicated that the as-prepared composite film presented better electrocatalytic activity, stability, CO tolerance ability, and electric conductivity towards formic acid oxidation as compared with commercial Pd/C catalyst. The enhancement in electrochemical performance of the Pd/PMo12-GN composite film can be attributed to the synergistic effect of highly dispersed Pd nanoparticles on the PMo12-GN substrate and higher oxidation power of PMo12 which promotes the removal of the poisonous species on the Pd surface.
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