焦磷酸盐溶液体系电沉积锡的动力学研究  

Research on kinetics of tin electrodeposition in aqueous pyrophosphate electrolyte

作　　者：郭艳[1] 曾振欧[1] 谢金平 范小玲 

机构地区：[1]华南理工大学化学与化工学院,广东广州510640 [2]广东致卓精密金属科技有限公司,广东佛山528247

出　　处：《电镀与涂饰》2014年第21期907-910,共4页Electroplating & Finishing

摘　　要：采用极化曲线法和循环伏安法研究了K4P2O7·3H2O＋Sn2P2O7溶液体系中Sn（Ⅱ）的阴极还原反应机理和动力学规律。结果表明，焦磷酸盐溶液体系电沉积Sn的表观活化能为13～14kJ／mol，即电极过程遵循扩散控制的动力学规律。Sn^2＋在焦磷酸盐溶液中的主要存在形式是[Sn（P2O7）2]^6-，但在阴极直接放电还原的是[Sn（P2O7）]^2-，电沉积锡的可能机理为：[Sn（P2O7）2]^6-←→[Sn（P2O7）]^2-＋P2O7^4-；[Sn（P2O7）]^2-＋2e^-→Sn＋P2O7^4-。The mechanism for the reduction of Sn（II） on cathode from K4P2O7·3H2O＋Sn2P2O7 solution system and relevant kinetic law were studied by measuring polarization curves and cyclic voltammograms. The results showed that the apparent activation energy of Sn electrodeposition in aqueous pyrophosphate electrolyte is 13-14 kJ/mol, that is, the electrode process follows the diffusion-controlled kinetic law. The main existence form of tin ion in the aqueous pyrophosphate solution is [Sn（P2O7）2]^6-, but the ion gains electrons directly and then reduced on cathode surface is [Sn（P207）]2-. The mechanism of tin electrodeposition is possibly as follows： [Sn（P2O7）2]^6- ←→ [Sn（P2O7）]^2- ＋ P2O7^4- , [Sn（P2O7）]^2- ＋ 2e^- → Sn ＋ P2O7^4-.

关 键 词：锡 电沉积 动力学行为 焦磷酸盐 配位离子 

分 类 号：TQ153.13[化学工程—电化学工业]