硫酸型镀铟电极过程动力学初探

Study on Electrode Process Kinetics of Indium Electroplating in Sulfate Electrolyte

过去用电化学方法对硫酸型镀铟工艺、作用机理研究较少。采用循环伏安、线性电位扫描和交流阻抗等电化学方法,研究了硫酸型镀铟中的阴极反应机理。结果表明:该体系内铟电沉积的最佳pH值为2~3,最佳温度为35~45℃;该阴极过程中存在前置化学反应和随后两个不可逆电化学反应,其中第一个电化学反应是控制步骤,其阴极过程电极反应标准常数为8.188×10-10cm/s。

The cathodic reaction mechanism of indium electroplating in a sulfate bath was investigated using several electrochemical methods such as cyclic volt-ampere measurement,linear voltage scanning,and electrochemical impedance spectroscopy.The results showed that the optimized pH value and temperature for the indium electrodeposition from the sulfate bath were 2~3 and 35~45 ℃,respectively.A preliminary chemical reaction and two non-reversible electrochemical reactions were involved in the cathodic process,and the first electrochemical reaction was the controlling step of the whole cathodic process.Moreover,the standard constant of the cathodic electrode reaction was determined to be 8.188×10^(-10) cm/s.