1,4-丁二醇在Pt及其修饰电极上吸附氧化过程研究

Abstract

运用电化学循环伏安和石英晶体微天平研究了1,4-丁二醇(1,4-BDL)在Pt电极及以Sb和S吸附原子修饰的Pt(Pt/Sbad和Pt/Sad)电极上的吸附和氧化过程.结果表明,1,4-丁二醇的氧化与电极表面氧物种有着极其密切的关系,表面质量变化提供了吸附原子电催化作用的新数据.Pt电极表面Sb吸附原子能在较低的电位下吸附氧,可显著提高1,4-丁二醇电催化氧化活性.与Pt电极相比,1,4-丁二醇在饱和吸附Sb原子的Pt电极上氧化的峰电位负移了0 20V,峰电流增加了1 5倍.相反,Pt电极表面S吸附原子的氧化会消耗表面氧物种,饱和吸附的S原子抑制了1,4-丁二醇的氧化.

The processes of adsorption and oxidation of 1,4-butanediol on Pt,Pt/Sbad and Pt/Sad electrodes were studied by using cyclic voltammetry and electrochemical quartz crystal microbalance(EQCM).The results demonstrated that the oxidation of 1,4-butanediol depends strongly on oxidation states of electrode surface.Sb adatoms on Pt surface can adsorb oxygen at relatively low potentials,and exhibit catalytic effects for 1,4-butanediol oxidation.In comparison with the case of Pt electrode,the oxidation peak potential of 1,4-butanedion on Pt surface modified with Sb was negatively shifted about 200 mV and the peak current was increased.On a contrary,the oxidation of S adatoms consumes oxygen species of Pt electrode surface.As a consequence,the oxidation of 1,4-butanediol was inhibited by the presence of Sad.The EQCM studies provided quantitative results of surface mass variation during 1,4-butanediol oxidation,and have thrown new light on elucidating different effects of adatoms Sbad and Sad on Pt electrode towards 1,4-butanediol oxidation.