导电高分子聚苯胺载铂电极的交流阻抗测定

Electrochemical Impedance Spectroscopy of Platinum Loaded onto Polyaniline Electrode

利用循环伏安方法电聚合导电高分子聚苯胺,用于在直接甲醇燃料电池电极中负载催化剂Pt.聚苯胺载Pt电极(Pt/PAni/C)的制备,提高了Pt的分散度,增加了Pt在电催化体系中的利用率.交流阻抗测试结果表明:Pt/PAni/C与直接碳载Pt电极(Pt/C)相比,电化学反应电阻减小,催化活性增高.通过比较Pt/PAni/C与Pt/C对甲醇的电催化氧化活性可知,Pt/PAni/C电极催化氧化甲醇的最大电流为50.7 mA/cm2,是Pt/C电极最大氧化电流(7.6 mA/cm2)的6.67倍.

Poyaniline is electropolymerized onto carbon paper to load Pt as electrode has been performanced by the cyclic voltammetric method. The polyaniline is found to have a significant bearing on the size of the platinum deposits,which may enable an increase in the level of platinum utilization currently achieved in these systems. The results of EIS confirm that the Pt/PAni/C electrode is not only higher catalyst activation but also lower charge-transfer resistance than the Pt/C electrode. The electroactivation of the methanol oxidized on carbon paper electrode（Pt/C） and onto polyaniline loading Pt electrode （Pt/PAni/C） are studied by cyclic voltammetry. The maximum oxidation current of methanol on Pt/PAni/C is 50.7 mA/cm^2 which is 6.67 times higher than 7.6 mA/cm^2 on the Pt/C.