CuCl2硅溶胶和水溶液中铜的电化学行为研究  

Electrochemical Behavior of Copper in CuCl_2 Silica Sol and Aqueous Solutions

作　　者：冯砚艳[1] 辜敏[1] 杜云贵[1] 

机构地区：[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

出　　处：《化学学报》2012年第7期831-837,共7页Acta Chimica Sinica

基　　金：重庆市科委科技计划项目院士专项(No.2008BC4003);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~~

摘　　要：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.Electrodeposition and electrocrystallization of copper on glass carbon electrode from both CuC12 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 （Cu^2＋ 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/nucleation 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 aque- ous solution. However, the saturated nuclear number density in sol was larger than that in the aqueous solu- tion at the same potential.

关 键 词：电结晶 电流-时间暂态曲线(CTTs) 硅溶胶 水溶液 CUCL2 铜 

分 类 号：O646[理学—物理化学]