铂电极上苯和苯磺酸吸附定向的现场红外反射吸收光谱电化学方法研究

本文用现场红外反射吸收光谱电化学方法和循环伏安法研究铂电析上苯和苯磺酸的吸附定向。对于苯/铂势系, 电势在-0.6至0.0V(相对饱和甘汞电极)内, 苯主要以垂直方式吸附; 在0.0至0.8V内则主要以平躺方式吸附。对于苯磺酸/铂体系,电势在-0.4V至0.0V内, 苯磺酸分子中的苯环主要呈垂直吸附且SO~3H基团远离电极表面; 在0.0至1.0V内则主要以倾斜平躺方式吸附, SO~3H基团通过其中的两个氧原子吸附于电极表面上。

An in-situ FTIR reflection-absorption spectroscopic study of adsorption and orientation of benzene and benzenesulfonic acid on pt electrode

The adsorption and orientation of benzene and benzenesulfonic acid on platinum electrode surface were studied using cyclic voltammetry and in-situ reflection-absorption spectroscopy. For benzene/Pt system, benzene rings were adsorbed perpendicularly to the electrode surface in the potential range -0.6-0.0 V (vs. SCE), while in the range 0.0-0.8 V, flat orientation was found to be predominant. For benzenesulfonic acid/Pt system, the benzene rings were adsorbed perpendicularly to the electrode surface with SO3H group pointed away from the electrode in potential range -0.4-0.0 V, while in the range 0.0-0.1 V the predominant orientation of benzene rings was probably tilted flat, and at same time the SO3H group was adsorbed to the surface through two oxygen atoms.