摘要
烷基醇聚氧乙烯醚(A-20)可明显提高三价铬电沉积、电镀的阴极电流效率,并可改善镀层表面质量。A-20没有电化学活性,不能用伏安法测定其含量。A-20在镀汞玻碳阴极上发生吸附,阻碍Cd2+还原,使峰电流定量下降。据此,用Cd2+作指示离子,利用方波伏安法可定量测定微量A-20的含量,其测定范围为0.5~20.0mg/L。加入50mg/L A-20阴极电流效率由19.3%上升到34.4%。
Non-ionic surfactant alkyi polyglycolether (A-20) can significantly improve the current efficiency in three -valence chromium electropllating and the quality of the coating as well. However, it is infeasible to measure A-20 by voltammetry, owing to the electrochemical inactivity. Fortunately, A -20 in solution containing Cd2+ is liable to be adsorbed on the surface of Hg- plated glass carbon cathode and retard the reduction of the Cd2+ ions, leading to a quantitative reduce in the peak current Thus Cd2+ ions were used as the indicator ions to determine the concentration of trace A-20 within a range of 0.5-20.0 mg/L. And the cathode electric efficiency was increased from 19. 3% to 34.4% when A-20 was introduced at a dosage of 50 mg/L
出处
《材料保护》
CAS
CSCD
北大核心
2008年第3期80-81,共2页
Materials Protection
基金
国家自然科学基金资助项目(50574006)
