聚(2,5-二甲氧基苯胺)膜修饰电极的电化学及催化性质

Electrochemical and Electrocatalytic Behavior of Poly-2,5-dimethoxyaniline Modified Electrode

由乳液聚合法得到的聚 ( 2 ,5 -二甲氧基苯胺 ) ( PDMAn)制作导电聚合物膜修饰电极 ,并在其上用电化学法沉积 Pt微粒 ,SEM与 XRD用于表征其表面形态与晶面取向 ,同时研究异丙醇在金属化 PDMAn膜修饰电极上的氧化行为 .结果表明 ,Pt在 PDMAn膜上的沉积呈现 ( 2 0 0 )晶面择优取向的现象 ,而且聚合物掺杂后 ,电化学活性增强 ,沉积 Pt微粒的尺寸和粒径分布也发生变化 .金属化聚合物电极是一种微相异相催化体系 ,虽然异丙醇的氧化主要发生在 Pt微粒上 ,但聚合物不单纯作为金属微粒的分散介质 。

The platinum particles were electrodeposited on poly(2,5 dimethoxyaniline)(PDMAn) membrane modified electrode. The polymer was obtained by emulsion polymerization. The surface configuration and crystal orientation of Pt particles have been investigated by SEM and XRD. The results of the oxidation of isopropanol on platinized PDMAn modified electrode show that Pt particles deposited towards preferred orientation on Pt(200), and, the increase in polymer electroactivity due to proton doping affects the dimension and graininess of deposited Pt particles. The metallized polymer modified electrode is proved to be a 'microheterogeneous catalysis system'. At the metallized polymer electrode the oxidation of isopropanol mainly took place on Pt particles, and the polymer not only plays a role as a dispersion medium but also affects the catalysis property of Pt particles.