分散铂修饰聚苯胺电极的制备及其催化性能

Effect of Preparation Conditions on Electrocatalytic Oxidation of Methanol of Pt-Modified Polyaniline Electrodes

利用扫描电子显微镜(SEM)、循环伏安(CV)方法,探讨了在合成分散铂修饰聚苯胺复合电极(Pt-PANi/pt)时能够影响聚苯胺表面形貌的质子酸种类以及铂微粒的电沉积方法。实验发现,采用循环伏安法制备聚苯胺时,在硝酸介质中制备的纳米聚苯胺纤维细小、膜层稳定、能够提高复合电极的催化活性,比在硫酸介质中制备的聚苯胺更适合作为Pt催化剂的载体;沉积分散铂所采用的电化学方法不同导致铂的生长方式不同,造成复合电极催化活性的差异。采用脉冲电位法,通过缩短脉冲沉积时间,能够使铂微粒数目增多、分布均匀,有效提高铂的比表面积,制备的Pt-PANi/pt复合电极显示出了较好的催化活性。

The electrocatalytic properties of Pt-modified polyaniline electrodes （Pt-PANi/Pt） are investigated for oxidation of methanol The electrochemical synthesis conditions of Pt-modified polyaniline electrodes are studied in this paper. It is found that PANi film prepared by cyclic voltammetry in nitric acid has larger specific surface area than PANi film prepared by cyclic voltammetry in sulfuric acid, which is more suitable as the matrix to incorporate Pt catalysts. Moreover, the growth of Pt particles is affected greatly by electrodeposition method. It is found that pulse potentiostatic method is a good method to deposit Pt particles and the electrocatalytic activity of Pt-PANi/Pt can be improved by pulse lasting time shortened.