铜电极表面铜锡合金电结晶机理.pdf

物理化学学报( Wuli Huaxue Xuebao
D
Acta Phys.-Chim.Sin.2013,29(12),2579-2584
2579
Article
doi:10.3866/PKU.WHXB201310092
www.whxb.pku.edu.cn
铜电极表面铜锡合金电结晶机理
史纪鹏杨防祖”田中群周绍民
(厦门大学化学化工学院,固体表面物理化学国家重点实验室,福建厦门361005)
摘要:在弱酸性柠檬酸盐体系铜锡合金镀液中,采用线性扫描伏安(LSV)循环伏安(C)和计时安培实验方
法,运用 Scharifker- Hills(SH)理论模型和 Heerman- Tarallo(HT)理论模型分析拟合实验结果,研究铜锡合金在
铜电极上的电沉积过程与电结品机理.结果表明,铜锡合金在铜电极表面实现共沉积并遵循扩散控制下三维瞬
时成核的电结晶过程.电位阶跃从-0.80V负移至-0.85V( VS SCE),HT理论分析得到铜锡合金的成核与生长
的动力学参数分别为成核速率常数(A)值从20.19s~1增加至1767s1,成核活性位点密度数(N)从6.10×10
cm?提高至1.42x10°cm2扩散系数(D)为(6.13t0.62)x10-°cm2·s
关键词:铜锡合金;电结晶;循坏伏安;计时安培曲线
中图分类号:O646
Electrocrystallization of Cu-sn Alloy on Copper Electrode Surface
SHI Ji-peng YANG Fang-zu TIAN Zhong-qun ZHOU Shao-min
(State Key Laboratory of Physical Chemisty of Solid Surfaces, College of Chemist and Chemical Engineering
Xiamen University, Xiamen 361005, Fujian Province, P R China
Abstract: The co-deposition and electrocrystallization of Cu-sn alloy in a weak acidic citrate bath were
studied by linear sweep voltammetry(SV), cyclic voltammetry(CV), and chronoamperometry. The Scharirker
Hil(SH)theory model and Heerman-taralo(HT theory model were applied to analyze the chronoam
erometry data. The results show that the Cu-sn alloy co-deposited on copper electrode, following instar
taneous nucleation with tree-dimensional (3D )growth under diffusion control. The kinetic parameters
were obtained using the H mode As the ste potential shifted from-080 to-085V, the nucleation rate
constant (A) increased from 20.19 to 177.67 s, the density of active nucleation sites()increased from
6.10×10°to1.42x10°cm2, and the diffusion coefficient(D)Was(6.13±0.62)x10°cm3s
Key Words: Cu-sn alloy; Electrocrystallization; Cyclic voltammetry; Chronoamperometry
1引言
在无络合剂的简单金属盐水溶液中,难以电沉积获
铜锡合金镀层具有较高耐蚀性.锡质量含量得Cu-Sn合金镀层.目前,电沉积铜锡合金的溶液基
o)在8%6-15%的低锡铜锡合金呈(金)黄色外观,本为剧毒的氰化物-锡酸盐体系近年来,针对行檬
可做为装饰性镀层;のs高于45%时则呈银白色,酸盐和焦磷酸盐为络合剂的无氰体系已有许多文
硬度介于镍与铬之间,是理想的代锞镀层.铜和献报道,°但大多侧重于工艺配方与参数优化、镀液
锡的标准电极电位分别为E(CuCu2)=0.340V、性能和镀层表征方面的研究;而对铜锡合金电沉积
EF(SnSn2)=-0.138V,二者电位相差0.478V.因此,机制与初期的成核和生长过程机理少有论述
Received: July 30, 2013; Revised: October 7, 2013 Published on Web: October 9. 2013
Corresponding author. Email fzyang(xmu.edu.cn; Tel: +-86-592-2185957: Fax: +86-592-2181436
he project was supported by the National Natural Science Foundation of China (21021002)and National Kcy Basic Research Program of China
(973)(2009CB930703)
因家自然科学基金(21021002)及国家重点基础研究发展计划(973)(2009CB930703)资助项日
ditorial office ofacta Ph