化学学报 ›› 2012, Vol. 70 ›› Issue (07): 831-837 .DOI: 10.6023/A1111151 上一篇    下一篇

研究论文

CuCl2 硅溶胶和水溶液中铜的电化学行为研究

冯砚艳, 辜敏, 杜云贵   

  1. 重庆大学复杂煤气层瓦斯抽采国家地方联合工程实验室 重庆大学煤矿灾害动力学与控制国家重点实验室 重庆 400044
  • 收稿日期:2011-11-15 修回日期:2012-02-12 出版日期:2012-04-14 发布日期:2012-02-21
  • 通讯作者: 辜敏, 杜云贵
  • 基金资助:

    重庆市科委科技计划项目院士专项(No. 2008BC4003)和厦门大学表面物理化学国家重点实验室2007 年度开放课题(No. 200703)资助项目.

Electrochemical Behavior of Copper in CuCl2 Silica Sol and Aqueous Solutions

Feng Yanyan, Gu Min, Du Yungui   

  1. State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam, State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044
  • Received:2011-11-15 Revised:2012-02-12 Online:2012-04-14 Published:2012-02-21
  • Supported by:

    Project was supported by the Chongqing Science and Technology Commission of Science and Technology Project of Academician Special (No. 2008BC4003) and the Foundation of State Key Laboratory of Physical Chemistry of Solid Surfaces of Xiamen University (No. 200703).

采用循环伏安法和计时安培法研究了CuCl2 硅溶胶和水溶液中铜在玻碳电极上的电沉积和电结晶行为. 结果表明在两种CuCl2电解质中, 铜的电沉积分两个步骤完成, Cu2+还原为Cu+在硅溶胶中较水溶液中容易; 采用吸附-成核模型解析电流-时间暂态曲线, 并确定铜的电结晶机理为扩散控制下的连续成核三维生长(3DP), Cu2+在水溶液中的扩散系数较硅溶胶中的大, 但相同电位下在硅溶胶中的饱和成核数密度高于水溶液中.

关键词: 电结晶, 电流-时间暂态曲线(CTTs), 硅溶胶, 水溶液, CuCl2,

Electrodeposition and electrocrystallization of copper on glass carbon electrode from both CuCl2 silica sols and aqueous solutions were investigated by utilizing cyclic voltammetry and chronoamperometry, respectively. The experiment results indicated that copper electrodeposition involved the two-step reaction in both electrolytes, and the deposition rate determining step (Cu2+ reduced to Cu+) in silica sol was easier than that in aqueous solution. An adsorption-nucleation model was proposed to analyze quantitatively the current-time transients (CTTs), which could separate the iDL and inucleation perfectly. By the proposed model, copper electrocrystallization mechanism was characterized as progressive nucleation with 3D growth (3DP) under diffusion control. The diffusion coefficient of copper ions in silica sol was smaller than that in aqueous solution. However, the saturated nuclear number density in sol was larger than that in the aqueous solution at the same potential.

Key words: electrocrystallization, current-time transients (CTTs), silica sol, aqueous, CuCl2, copper