Au(111)电极上CTAB吸脱附过程的循环伏安研究

Cyclic Voltammetric Studies in Adsorption of Cetyltrimethylammonium Bromide(CTAB) on Au(111) Electrode

本文运用循环伏安方法研究十六烷基三甲基溴化铵(CTAB)在Au(111)电极上的吸附行为.给出CTAB在Au(111)电极上的循环伏安曲线,其0.18 V、0.27 V有2对可逆的特征电流尖峰,均受扩散控制,且与卤素离子种类有关.研究表明,烷基铵阳离子的吸脱附及吸附层相转变与Au(111)电极表面结构密切相关.

Adsorption ofcetyltrimethylammonium bromide（CTAB） on Au（111） electrode was investigated by cyclic voltammetry （CV）.The results demonstrate that the adsorption of CTAB on Au（111） yields particular CV features. Both the adsorption of CTA~ and the phase change of the surfactant film are surface structure selective. Two pairs of stable sharp peaks that depend on halide speciesappear upon the adsorption of cationic surfactant on Au（111） electrode. The relationship between the peak current density and the scan rate indicates that the electron transfer reaction was controlled by diffusion process. These CV featuresare observed for the first time, and reflect the specific interaction between CTAB and Au（111）. The results are of significance in understanding the interaction of CTAB with Au surface for shape-control synthesis of Au nanoparticles.