物理化学学报 >> 2007, Vol. 23 >> Issue (10): 1607-1611.doi: 10.3866/PKU.WHXB20071022

研究简报 上一篇    下一篇

羧酸盐尿素体系中三价铬电沉积机理

马立文; 陈白珍; 何新快   

  1. 中南大学冶金科学与工程学院, 长沙 410083; 湖南工业大学包装与印刷学院, 湖南 株洲 412008
  • 收稿日期:2007-03-05 修回日期:2007-06-20 发布日期:2007-10-01
  • 通讯作者: 陈白珍 E-mail:yhschen@mail.csu.edu.cn

Mechanismof Cr(III) Electrodeposition in Carboxylic Acid-Urea System

MA Li-Wen; CHEN Bai-Zhen; HE Xin-Kuai   

  1. School of Metallurgical Science and Engineering , Central South University, Changsha 410083, P. R. China; School of Packaging and Printing, Hunan University of Technology, Zhuzhou 412008, Hunan Province, P. R. China
  • Received:2007-03-05 Revised:2007-06-20 Published:2007-10-01
  • Contact: CHEN Bai-Zhen E-mail:yhschen@mail.csu.edu.cn

摘要: 采用循环伏安法、线性扫描法及交流阻抗技术研究了羧酸盐尿素体系Cr3+电沉积机理. 结果表明, 该体系中Cr3+电沉积有前置反应存在, Cr3+放电分两步进行, 分别得1个电子和2个电子, 均不可逆; 且第一步放电步骤是速率控制步骤. 由机理推导的电极反应动力学方程, 计算了电化学反应级数、Tafel斜率、表观传递系数的理论值, 其与实验值相吻合.

关键词: 三价铬; 羧酸盐; 尿素; 机理; 动力学方程

Abstract: Cyclic voltammetry, steady polarization and alternating current impedance were used to study the mechanism of Cr(III) electrodeposition in carboxylic acid-urea system. The results indicated that the trivalent chromium ion got three electrons by two steps in which one electron was got firstly and two secondly. The two steps were all nonreversible reductions with chemical transformation. The kinetic parameters, such as reaction orders, Tafel slopes and apparent transfer coefficients calculated from the theoretical kinetics equation were agreed well with the experimentally measured ones.

Key words: Trivalent chromium, Carboxylic acid, Urea, Mechanism, Kinetics equation

MSC2000: 

  • O646