物理化学学报 >> 2006, Vol. 22 >> Issue (04): 419-423.doi: 10.1016/S1872-1508(06)60013-2

研究论文 上一篇    下一篇

Pt/C催化剂的硅钼酸电化学修饰

李莉;武刚;叶青;邓炜;徐柏庆   

  1. 清华大学化学系, 有机光电子与分子工程教育部重点实验室, 分子催化与定向转化研究室, 北京 100084
  • 收稿日期:2005-10-10 修回日期:2005-11-20 发布日期:2006-04-10
  • 通讯作者: 徐柏庆 E-mail:bqxu@mail.tsinghua.edu.cn

Electrochemical Modification of Pt/C Catalyst by Silicomolybdic Acid

LI Li;WU Gang;YE Qing;DENG Wei;XU Bo-Qing   

  1. Innovative Catalysis Program, Key Laboratory of Organic Optoelectronics and Molecule Engineering, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China
  • Received:2005-10-10 Revised:2005-11-20 Published:2006-04-10
  • Contact: XU, Bo-Qing E-mail:bqxu@mail.tsinghua.edu.cn

摘要: 通过电化学循环伏安法将硅钼酸修饰到Pt/C催化剂表面, 比较了硅钼酸修饰对Pt/C催化剂上CO、甲醇及乙醇电氧化反应的影响. CO消除伏安测试结果表明, 用硅钼酸修饰后的Pt/C催化剂上吸附的CO的起始氧化电势和峰电势, 与修饰前相比分别降低了80和60 mV, 表明修饰后Pt/C催化剂的抗CO性能有明显提高. 对于甲醇的电氧化反应, 硅钼酸的修饰不仅提高了甲醇电氧化的电流密度, 而且降低了甲醇的起始氧化电势, 促进了中间氧化产物的脱除;而在乙醇的电氧化反应中, 硅钼酸修饰虽对Pt/C催化剂上乙醇的起始氧化电势没有影响, 但能增加乙醇电氧化的电流密度.

关键词: 质子交换膜燃料电池, 抗CO中毒催化剂, 硅钼酸, 醇类电氧化, CO电氧化

Abstract: Modification of conventional Pt/C electrocatalyst with silicomolybdic acid (SiMoA) was performed using electrochemical cyclic voltammetry method. The modified and unmodified catalysts were tested under identical conditions for the electrooxidation of CO, methanol, and ethanol. In the CO stripping experiments, the modified catalyst was characterized by significant shifts (80 and 60 mV) to lower onset potential and peak potentials for CO electrooxidation, suggesting better CO tolerant property of the modified catalyst. In the electrooxidation of methanol and ethanol, the modified catalyst was featured by significantly increased current densities due to reduced residence time of the reaction intermediates, showing significantly higher electrocatalytic activity for electrooxidation of alcohols.

Key words: PEMFCs(proton exchange membrane fuel cells), CO tolerance catalysts, Silicomolybdic acid, Alcohols electrooxidation, CO electooxidation