2种有机添加剂对锡电沉积的影响  

Effect of Two Organic Additives on Tin Electrodeposition

作　　者：李俊华[1] 费锡明[1] 徐芳[1] 

机构地区：[1]华中师范大学化学学院,武汉430079

出　　处：《应用化学》2006年第9期1042-1046,共5页Chinese Journal of Applied Chemistry

摘　　要：运用循环伏安、电势阶跃和交流阻抗等电化学方法研究了酸性镀锡溶液中苄叉丙酮(4-苯基-3-丁烯-2-酮)和SN-A等有机添加剂对锡电沉积的影响。结果表明,加入有机添加剂后锡电沉积过程的阴阳极峰电位之差达0.9 V,说明其电极过程不可逆;伏安图上同时出现一感抗性电流环,说明锡沉积过程中发生晶核形成过程。苄叉丙酮和SN-A都能阻化锡的沉积,增大了阳极极化。加入苄叉丙酮后锡沉积的电化学阻抗Rct值为1.5×104Ω.cm2,比SN-A增大很多,并能阻化H2气的析出。当这2种添加剂联合作用时,锡电沉积的阴极过电位增大280 mV,更有利于得到光亮锡层;加入有机添加剂后锡电沉积I2/I2m^t/tm实验曲线均靠近瞬时成核理论曲线,说明锡沉积遵循瞬时成核三维生长的电结晶机理。Effect of 2 organic additives, acetone and SN-A, on tin electrodeposition in acid solution was investigated by cyclic vohammetry, potential step, and AC impedance. The results show that the potential seperation between anodic and cathodic peaks in the electrodeposition of tin with the organic additives added reached up to 0. 9 V, indicating that the electrode process was irreversible. In addition, an inductive current cycle appeared, which indicated the presence of nucleation. It was found that acetone and SN-A inhibited tin electrodeposition, leading electrodeposition in the to a more negative deposition potential of tin. The electrochemistry impedance Ro, of presence of acetone additive was 1.5 × 10^4Ω·cm^2, which is much larger than that caused by SN-A additive. Acetone could also inhibit hydrogen evolution. The cathode overpotential of tin electrodeposition in the presence of the two organic additives increased 280 mV, which is benefical to the gloss of the tin layer. The I^2/I^2m - t/tm curves of tin electrodeposifion was close to theoretical instantaneous nucleation curve. The electrocrystallization of tin in the presence of organic additives followed the mechanism of instanta- neous nucleation and three dimensional growth.

关 键 词：有机添加剂 电沉积 循环伏安 交流阻抗 

分 类 号：O646[理学—物理化学]