烟酸对酸性硫酸盐体系铜电沉积的影响

Effects of Nicotinic Acid on Copper Electrodeposition in Acid Sulphate

对溶液A:0.8mol·L-1硫酸铜,0.6mol·L-1硫酸,5.0×10-5mol·L-1氯离子,1.0×10-4mol·L-1聚乙二醇的溶液,溶液B:在溶液A中加入2.0×10-2mol·L-1烟酸,pH为0.5,运用循环伏安和计时安培法研究玻碳电极上铜的电沉积行为.结果表明,铜的电沉积过程经历了晶核形成过程,其电结晶按瞬时成核和三维生长方式进行.烟酸的加入对铜的电沉积具有阻化作用,但不改变铜的电结晶机理.沉积层的X射线衍射表明Cu为面心立方结构,在烟酸存在下沉积层出现(220)高择优取向,这可能是烟酸在Cu(220)晶面上发生强烈吸附作用的结果.

Initial stages of electrodeposition of copper on glassy carbon electrode from 0.8 mol·L-1 copper sulphate electrolyte solution containing 2.0×10-2 mol·L-1 nicotinic acid are studied using cyclic voltammetry and chronoamperometry.The results show that nicotinic acid (NA) produces an inhibition of copper deposition,probably related to the adsorption of nicotinic acid.The initial deposition kinetics corresponds to a model including instantaneous nucleation and diffusion controlled growth.The X ray diffraction results indicate that copper deposits exhibit face centered cubic structure and (220) highly preferred orientation.Nicotinic acid produces uniform and smooth surfaces of copper deposit.