Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (03): 641-646.doi: 10.3866/PKU.WHXB20110322

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Mechanism of Au Electrodeposition onto Indium Tin Oxide

TANG Jing1, TIAN Xiao-Chun1, ZHOU Fu-Qing1, LIU Yue-Qiang1, LIN Jian-Hang2   

  1. 1. Key Laboratory of Analysis and Detection Technology for Food Safety, Ministry of Education, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108, P. R. China;
    2. Instrumental Measurement and Analysis Center, Fuzhou University, Fuzhou 350002, P. R. China
  • Received:2010-10-21 Revised:2010-12-07 Published:2011-03-03
  • Contact: TANG Jing E-mail:jingtang@fzu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20873112) and Fund of National Engineering Research Center for Optoelectronic Crystalline Materials, China (2005DC105003).

Abstract:

Cyclic voltammetric and chronoamperometric methods were used to study the initial stage of Au electrodeposition on an indium tin oxide (ITO) surface. The nucleation process was controlled by the diffusion of [AuCl4]-. The cyclic voltammetry curves showed that the electrochemical reduction included two steps which were [AuCl4]-→ [AuCl2]-, and [AuCl2]- → Au. Only one reduction peak was observed when the scan rate was comparatively slow and this peak separated into two peaks when the scan rate was increased. This phenomenon resulted from the disproportionation of [AuCl2]- during the electrodeposition process. Chronoamperometry also proved the two step reaction mechanism and the diffusion coefficient of [AuCl4]- was calculated to be 1.3×10-5 cm2·s-1. From the theoretical nucleation curves, an instantaneous three-dimensional nucleation mechanism was proposed for the nucleation of gold on ITO. Au electrodeposits were observed by field emission scanning electron microscopy (FE-SEM). SEM images of the electrodeposits showed that the morphology of the gold deposits was affected by the electrochemical deposition potential and time.

Key words: Indium Tin Oxide, Au nano particle, Electrodeposition, Nucleation mechanism

MSC2000: 

  • O646