含氧复合型Pt/C催化剂的制备、表征及其对甲醇电氧化催化性能的研究
Preparation and characterization of oxo composite Pt/C catalyst and study on its catalytic performance for electro-oxidation of methanol
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摘要: 利用亚锡酸对氯铂酸的弱的多步骤还原制备新型Pt/C催化剂.用XRD、HRTEM、EDS、DSC以及氢吸附电化学对所制备的催化剂进行了表征,并用循环伏安和恒电位极化对其进行了甲醇电氧化催化活性测定.实验结果表明,应用亚锡酸法合成的Pt/C催化剂具有很高的甲醇电氧化催化活性,在0.5V(SCE)电位下,其质量活性约为亚硫酸路线合成的Pt/C催化剂的2倍.亚锡酸法可在纳米尺度范围内生成金属Pt和Pt氧化物共存的复合型碳载催化剂,这种含氧复合型催化剂可以促进Pt在甲醇电氧化过程中双功能作用的有效协调.Abstract: The weak multi-step reduction of stannous acid on hexachloroplatinic acid was utilized to prepare a new type of Pt/C catalyst. The catalyst was characterized by XRD, HRTEM, EDS, DSC and H-adsorption electrochemistry, and its catalytic activity for electro-oxidation of methanol was estimated by cyclic voltammogram and potentialstatic steady-state polarization. The results indicate that Pt/C catalyst prepared by the new method is with high activity for electro-oxidation of methanol which possesses about two-fold mass activity at 0.5 V (SCE) compared with Pt/C prepared by sulfurous route. The stannous method can produce a composite carbon-supported catalyst with Pt metal and Pt oxides co-exiting within nanometer dimension. The oxo composite catalyst could enhance the harmony of the hi-function of Pt during electro-oxidation of methanol.