摘要
应用循环伏安、恒电位阶跃和X射线衍射 (XRD)等方法研究了Ni_W_B合金电沉积特点和镀层微晶尺寸 .结果表明 ,在以柠檬酸铵为络合剂的溶液中 ,Ni_W_B合金沉积层较Ni_W合金有较低的电化学活性 .电位阶跃i～t曲线分析表明 ,在玻碳电极上Ni_W_B合金电结晶过程遵循扩散控制瞬时成核三维成长模式 ,且随过电位的增加 ,电极表面晶核数增多 .XRD测试结果表明 ,随沉积电流密度提高 ,合金镀层微晶尺寸逐渐增大 ,说明电流密度提高将更加有利于Ni_W_B合金电结晶过程中的晶核生长 .
The electrodeposition characteristics and grain sizes of Ni_W_B alloy have been studied by cyclic voltammetry, potentiostatic step and X_ray diffraction (XRD). The results showed that Ni_W_B alloy electrodeposit obtained from the solution containing ammonium citrate as a complexing agent was presented in the lower electrochemical activity compared with Ni_W alloy. Based upon the i～t curves of potentiostatic step, it was revealed that electrocrystallization of Ni_W_B alloy on glassy carbon followed the mechanism of instantaneous nucleation and three dimensional growth with diffusion controlled. The crystal nucleus number on the surface of electrode was raised by the increase of overpotential. According to XRD experimental results, the grain sizes of the alloy deposits were gradually increased by the rising of deposition current densities, which elucidates that the increase of current density was more benefit to nucleus growing during the electrocrystallization of Ni_W_B alloy.
出处
《电化学》
CAS
CSCD
2000年第2期169-174,共6页
Journal of Electrochemistry
基金
国家自然科学基金!资助项目 (2 97730 39)
