在硫酸盐电解液中的Zn＿Co合金共沉积,存在着由正常共沉积转变成异常共沉积的Zn转移电流密度,该值随着电解液中所含SCN-浓度的增加而增加,pH值的增加而减小.这主要是因为SCN-降低了Co的析出过电位,但不影响Zn及H2的析出过电位之故.
For co_deposition of Zn_Co alloys at sufphate baths with micro_concentration of SCN- the transition current of Zn was found with the deposition process changing from normal Co_deposition to anomalous co_deposition, and the value of transition current increased with increasing SCN- concentration, but decreased with increasing value of pH. The existence of SCN- decreases the evolution overpotential of Co metal, but has no effects on the evolution overpotential of Zn metal and H2.
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