摘要
采用紫外–可见分光光度法(UV–vis)和电化学分析法研究了尿素对Cr(III)–甲酸盐镀液体系电沉积过程的作用机理。UV–vis谱图表明,尿素可参与Cr(III)–甲酸盐镀液体系的配位取代反应。线性扫描伏安曲线和恒电位电沉积试验表明,尿素可提高Cr(III)–甲酸盐体系中铬的沉积过电位,并抑制析氢反应。不同配位体系所得镀层的表面形貌表明,尿素可细化Cr(III)–甲酸盐镀液体系电沉积铬的晶核。
The mechanism of the effect of urea on electrodeposition of chromium from a Cr（Ⅲ）--formate electrolyte was studied by ultraviolet-visible （UV-vis） spectrophotometry and electrochemical analysis. UV-vis spectra show that urea takes parts in the complex substitution in Cr（Ⅲ）-formate plating bath. Linear sweep voltammetric curves and potentiostatic electrodeposition test indicate that urea can raise the deposition overpotential of chromium in Cr（Ⅲ）-formate plating system and inhibit hydrogen evolution. Surface morphologies of the coatings prepared from plating baths with different complexing agents show that chromium grains can be refined by urea in Cr（Ⅲ）-formate plating system.
出处
《电镀与涂饰》
CAS
CSCD
北大核心
2013年第9期5-8,共4页
Electroplating & Finishing
关键词
三价铬
电沉积
尿素
配位剂
电化学
机理
trivalent chromium
electrodeposition
urea
complexing agent
electrochemistry
mechanism
