应用化学 ›› 1990, Vol. 0 ›› Issue (6): 37-42.

• 研究论文 • 上一篇    下一篇

高氯酸与硫酸溶液中铂电极上氧阳极析出动力学与机理

金世雄, 王岚, 朱志昂   

  1. 南开大学化学系 天津 300071
  • 收稿日期:1989-07-07 修回日期:1990-04-07 出版日期:1990-12-10 发布日期:1990-12-10

KINETICS AND MECHANISMS OF OXYGEN EVOLUTION ON Pt ANODE IN HCIO4 and H2 S04 SOLUTIONS

Jin Shixiong, Wang Lan, Zhu Zhi'ang   

  1. Department of Chemistry, Nankai University, Tianjin 300071
  • Received:1989-07-07 Revised:1990-04-07 Published:1990-12-10 Online:1990-12-10

摘要: 本文研究了不同浓度的HClO4和H2SO4溶液中铂电极上氧阳极析出过程的动力学。稳态极化曲线上有三个区域:电位突跃前的低极化区,突跃区和突跃后的高极化区。前两个区域内对于αw的反应级数均为1,在后一区域内对于αw·αClO4-或αw·αHSO4-的反应级数接近于1/2。文中对在各区域内的反应机理和产生电位突跃的原因进行了探讨。

关键词: 氧的析出, 铂阳极, 动力学, 机理

Abstract: in φ-lgi relations steady-state were determined for the O2 evolution on Pt electrode in HClO4 and H2SO4 solutions of concentrations from 0.05-40mol·kg-1. There are three regions on the φ-lgi curves. The first is the lower overpotential region with ∂φ/∂lgi = 2.303RT/βF(β= 0.5), followed by the second potential jump region, and then the third regionagain with a Tafel slope of approximately to 2.303θRT/βF. The reaction order of O2 evolu-tion with respect to aw was found to be 1 in the first and second regions, while in the third region the reaction order of O2 evolution with respect to aw·aClO4- or aw·aHSO4-was found to be 1/2. Possible mechanisms for oxygen evolution were proposed. Some of them explain quite satisfactorily the difference in Tafel slope in different region of polarization curves and thevarious order of reaction with respect to different reactants.

Key words: oxygen evolution, platinum anode, kinetics, mechanism