Acta Phys. -Chim. Sin. ›› 2007, Vol. 23 ›› Issue (06): 964-968.doi: 10.3866/PKU.WHXB20070634

• Note • Previous Articles    

Influence of m-4-m Structured Gemini Surfactants on the Adsorption-Stripping Voltammetric Behavior of Methylene Blue on a Platinum Electrode

PAN Shen-Min; ZHOU Qin; ZHAO Fa-Qiong; ZENG Bai-Zhao   

  1. College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, P. R. China

  • Received:2006-10-27 Revised:2006-12-26 Published:2007-06-04
  • Contact: ZHAO Fa-Qiong E-mail:zhaofq@chem.whu.edu.cn

Abstract:

In 0.050 mol·L-1 phosphate buffer solution (pH=6.4), methylene blue (MB) exhibited a pair of small peaks at about -0.2 V on a platinum electrode. In the presence of m-4-m structured Gemini surfactants, such as Br-C16H33N+-(CH3)2-C4H8-N+(CH3)2C16H33Br-, Br -C12H25N+(CH3)2-C4H8-N+(CH3)2C12H25Br-, and Br -C8H17N+(CH3)2-C4H8-N+-(CH3)2C8H17Br-, the anodic peak of MB grewrapidly but the cathodic peak decreased, and the peak potentials moved in positive direction due to the associated adsorption of Gemini surfactants and MB on the electrode surface. The influence of Gemini surfactants increased with their length of alkyl chain growing. When their concentrations were enhanced, the anodic peak increased firstly and then lowered. For Br-C16H33N+(CH3)2-C4H8-N+(CH3)2C16H33Br- the anodic peak of 5 μmol·L-1 MB achieved the maximum when its concentration was 15 μmol·L-1. In addition, solution pH and accumulation potential also showed effect on their adsorption behavior.

Key words: Gemini surfactants, Methylene blue, Adsorption-stripping voltammetry, Platinumelectrode

MSC2000: 

  • O647