铂电极上Kolbe反应的现场FTIR反射吸收光谱研究

IN SITU FTIR REFLECTION ABSORPTION SPECTROSCOPIC STUDY OF KOLBE REACTION ON PLATINUM ELECTRODE

用现场红外反射吸收光谱和电化学方法研究了铂电极上CH_3COOH—CH_3COONa水溶液体系的电化学行为。当电极电势(相对SCE)从零伏调至1.8伏时,电极表面附近发生了乙酸-乙酸钠酸碱平衡移动,电极电势从1.8伏调至2.2伏时,电极表面发生了乙酸-乙酸钠体系的氧化反应(Kolbe反应)及其中间过程。根据实验结果讨论了此Kolbe反应的两种可能机理。

The behaviors of acetic acid-sodium acetate and its KOLBE reaction on platinum electrode were studied using in-situ FTIR reflection-absorption spectroscopy(SN IFTIRS) and electrochemical method.When potential was modulated from 0.0Ⅴ to 1.8Ⅴ(vs.SCE),the shift of acid-base equili-brium between acetic acid and sodium acetate was found to occur near electrode surface.When potential was shifted from 1.8Ⅴ to 2.2Ⅴ, the KOLBE reaction of acetic acid-sodium acetate was observed. According to the experimental results two possible reaction modes were discussed.