摘要
运用循环伏安、交流阻抗和电势阶跃等电化学方法研究了酸性电解液中苄叉丙酮、香草醛和OP-10 3种有机添加剂对锌镍合金电沉积的作用机理。结果表明,加入有机添加剂后均能使锌镍合金电沉积电位负移,当苄叉丙酮和OP-10联合作用时,锌镍电沉积阴极超电势最大,并能有效阻化氢气析出,更有利于得到光亮锌镍合金镀层。同时伏安图上出现一感抗性电流环,说明锌镍电沉积过程中发生晶核形成过程;其氧化还原峰电位之差达0.55 V,说明其电极过程明显不可逆。加入有机添加剂后锌镍合金电沉积受电化学极化和浓差极化混合控制;且锌镍电沉积I2/I2m^t/tm实验曲线靠近瞬时成核理论曲线,说明在有机添加剂作用下锌镍合金的电沉积遵循瞬时成核三维生长的电结晶机理。
The mechanism of three kinds of organic additives including benzalacetone,vanillin and OP-10 on electrodeposition of zinc-nickel alloy in acidic electrolyte was investigated by electrochemical methods such as cyclic voltammetry,AC impedence,and electric potential step.The test results showed that the electrodeposition potential of zinc-nickel alloy shifted negatively in the presence of organic additives.The cathode overpotential of zinc-nickel electrodeposition was the greatest and the delivery of hydrogen was restrained effectively by the joint actions of benzalacetone and OP-10,which were also beneficial for achieving brightness in coatings of zinc-nickel alloy.An inductive current cycle appeared at cyclic voltammogram,indicating to the process of nucleation.The potential difference between the oxidation peak and the reduction peak was up to 0.55 V,which showed that the electrode process was irreversible.The zinc-nickel electrodeposition was controlled by concentration polarization and electrochemical polarization after addition of organic additives.The I2/I2m～t/tm curve of zinc-nickel electrodeposition with organic additives was close to the theoretical instantaneous nucleation curve,which showed that the electrocrystallization of zinc-nickel alloy with organic additives followed the mechanism of instantaneous nucleation with a three-dimensional growth.
出处
《化学试剂》
CAS
CSCD
北大核心
2011年第2期152-156,共5页
Chemical Reagents
基金
衡阳市工业科技支持计划项目(2009KG23、2009KG50)
衡阳师范学院科学基金资助项目(09A32)
关键词
有机添加剂
锌镍合金
电沉积
作用机理
organic additives
zinc-nickel alloy
electrodeposition
mechanism
