以钨粉为钨源,酚醛树脂(PF)为碳源,采用溶胶-凝胶法合成纳米碳化钨(WC).以甲醛(HCHO)为还原剂,在含有纳米WC的氯铂酸(H2PtCl6·6H2O)悬浮液中还原氯铂酸制备纳米WC负载纳米Pt的复合粒子,再采用Nafion 溶液制备质子交换膜燃料电池工作电极.运用傅立叶红外光谱(FTIR)、X射线衍射(XRD)、扫描电镜(SEM)及透射电镜(TEM)等对前驱体及试样进行表征,并在酸性介质中采用循环伏安法测试工作电极的电化学催化活性.结果表明:采用溶胶-凝胶工艺制备的WC沿(100)晶面择优取向,其晶面间距为0.25nm,Pt主要沿(111)晶面择优取向,其晶面间距为0.23nm.10wt％ Pt/WC在0.5mol/L H2SO4中的催化电流密度达到28.5mA/cm2,并发现纳米WC与Pt之间存在协同催化作用.%Nano-WC particles were prepared by Sol-Gel using tungsten powder as the tungsten source and phenol formaldehyde resin as carbon source. The working electrode of proton exchange membrane fuel cell was obtained from taking Nafion coating solution to the surface of the Pt/WC composite particles which was synthesized by reduction of H2PtCl6·6H2O using carbinol (HCHO) as reducing agent from the suspended liquid mixed H2PtCl6·6H2O and WC. Fourier transform infrared spectroscope (FITR), X-ray diffraction (XRD), SEM and transmission electron microscope (TEM) were used to characterize the samples and the precursors, and used cyclic voltammetry to test the electrochemical activity of working electrode. The results showed that WC of (100) preferred orientation could be fabricated by Sol-Gel method, its interplanar spacing was 0.25nm, and the interplanar spacing of Pt was 0.23nm with preferential orientation of (111). The current density of 10wt% Pt/WC was up to 28.5mA/cm2 in 0.5mol/L H2SO4, and the synergistic catalytic effect was found between nano-WC and Pt.
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