应用离子交换法制备了40% Pt在-Mo2C/GC上的电催化剂. X射线衍射(XRD)显示，Pt在Mo2C载体上有较好的分散度，平均粒径为3 nm.循环伏安、计时电位测试表明，酸性溶液中,Pt-Mo2C/GC具有良好的甲醇氧化性能. 其催化甲醇氧化的起始电位比Pt/C的负移了90 mV. 这一优异性能与Pt和载体Mo2C之间的协同作用有关. 现场红外光谱电化学测量显示，甲醇在Pt/C电极氧化的中间产物是桥式吸附COB和线性吸附COL，而在Pt-Mo2C/GC电极则未检测到有害中间产物CO，其氧化终产物均为CO2.
A 40% Pt on Mo2C/GC catalyst has been prepared by ion exchange method. The mechanism of methanol electrooxidation on Pt-Mo2C/GC and commercial Pt/C catalysts in acidic media was studied by cyclic voltammetry, XRD measurements and in-situ Fourier transform infrared spectroelectrochemistry. The results revealed that the Pt nanoparticles were uniformly dispersed on Mo2C/GC with an average particle size of 3 nm. The cyclic voltammetric and chronopotentiometric experiments indicated that Pt-Mo2C/GC catalyst exhibited a better performance for methanol oxidation than that of Pt/C in acid solution. A negative shift over 90 mV of the onset potential for methanol oxidation was found on Pt-Mo2C/GC compared with that on Pt/C. The in situ FTIR spectroelectrochemical measurements indicated that the intermediate products of methanol oxidation on Pt/C catalyst were bridge COB and linear COL. No CO was detected on Pt-Mo2C/GC catalyst during the oxidation of methanol by FTIR spectroscopy, indicating the electrooxidation was a non-poisoning process.
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