Mechanism of zinc electroplating in alkaline zincate solution  

作　　者：彭文杰 王云燕 

机构地区：[1]School of Metallurgical Science and Engineering,Central South University

出　　处：《Journal of Central South University of Technology》2007年第1期37-41,共5页中南工业大学学报（英文版）

基　　金：Project(50274073) supported by the National Natural Science Foundation of China

摘　　要：The cathodic deposition properties and mechanism of Zn in alkaline zincate solution were studied by electrochemical techniques. The results show that Zn2+ exists in the alkaline solution in the form of Zn(OH)42-. The apparent activation energy of the electrode reaction is 38.93 kJ/mol, which indicates that the discharge of Zn(OH)42- on cathode is controlled by electrochemical polarization, and accompanied by a preceding chemical reaction. The diffusion coefficient of Zn(OH)42- is 2.452×10-6 cm2/s. Zn(OH)2 is the species directly discharged on the cathode surface. Based on the above results the mechanism of zinc electroplating in alkaline zincate solution was put forward. The discharged species is Zn(OH)2 formed from the preceding chemical reaction, which becomes Zn(OH)ad when gaining one electron, and then gaining the second electron to become Zn. The first electron gaining step is rate determining one.The cathodic deposition properties and mechanism of Zn in alkaline zincate solution were studied by electrochemical techniques. The results show that Zn^2＋ exists in the alkaline solution in the form of Zn（OH）4^2-. The apparent activation energy of the electrode reaction is 38.93 kJ/mol, which indicates that the discharge of Zn（OH）4^2- on cathode is controlled by electrochemical polarization, and accompanied by a preceding chemical reaction. The diffusion coefficient of Zn（OH）4^2- is 2.452 × 10^-6 cm^2/s. Zn（OH）2 is the species directly discharged on the cathode surface. Based on the above results the mechanism of zinc electroplating in alkaline zincate solution was put forward. The discharged species is Zn（OH）2 formed from the preceding chemical reaction, which becomes Zn（OH）ad when gaining one electron, and then gaining the second electron to become Zn. The first electron gaining step is rate determining one.

关 键 词：Zn electroplating MECHANISM ALKALINE ZINCATE 

分 类 号：TQ153.15[化学工程—电化学工业]