苯酚在多壁碳纳米管修饰的玻碳电极表面的电氧化机理研究

Study on Mechanism of Phenol Electrooxidation on MWCNT Modified Glassy Carbon Electrode

以含有苯酚的PBS溶液为电解液,采用循环伏安法研究了苯酚在碳纳米管修饰的玻碳电极表面电化学氧化的机理。结果表明,苯酚在碳纳米管修饰的电极表面的氧化机理为:苯酚先于正向扫描中不可逆氧化为苯醌后,在负向扫描中被还原为对苯二酚和邻苯二酚,对苯二酚和邻苯二酚可进一步发生可逆氧化还原反应而存在于溶液中。对苯二酚和邻苯二酚的生成对苯酚氧化形成苯醌的峰电流产生干扰,从而影响苯酚电化学测定的灵敏度和准确性。

The mechanism of phenol electrooxidation on multi-wall carbon nanotube modified glassy carbon electrode was studied by cyclic voltammetry in phosphate buffer solution. The mechanism was as follows ： phenol was irreversibly electrooxidized to benzoquinone in the positive scan, and benzoquinone was then reduced to hydroquinone and catechol in the negative scan, which could further occur reversibly redox reaction. The existence of hydroquinone and catechol would affect the sensitivity and accuracy of the electrochemical measurement of phenol.