氰化镀铜及乙二胺无氰碱性铜镀体系的EIS研究

Study on EIS of System for Cyanide Electroplating Copper and Cyanide-free Electroplating Copper

以乙二胺为络合剂,研究和测量了氰化镀铜体系和乙二胺无氰镀铜体系的电化学交流阻抗(EIS),考察了乙二胺浓度和pH对EIS的影响。研究结果表明,氰化镀铜体系的电荷转移电阻小,铜离子放电速度快,同时存在电化学极化和浓差极化,这可能是氰化镀铜镀层结合力好的原因之一;乙二胺无氰镀铜体系中,当乙二胺浓度为0.45 mol.L-1,pH=9.0时,电荷转移电阻较小,并且EIS图和氰化镀铜体系的相似。

The electrochemical impedance spectroscopy（EIS） of systems for cyanide electroplating copper and cyanide-free electroplating copper were measured and studied using ethylenediamine as complexing agents. The effects of the concentration of the complexing agents and pH value of the system were discussed. The result shows that for the system of cyanide electroplating copper, resistance of charge transfer is small, the speed of the discharge copper ions is high and there occurs concentration difference polarization. This may be one of the reasons of good combining on electroplating plate in the system of cyanide electroplating copper. When the ethylenediamine concentration is 0.45 mol·L^-1 and pH=9, resistance of charge transfer is small and its EIS plot is similar to that of the cyanide electrolyte in the system of ethylenediamine cyanide-free electroplating copper.