Pt电极上吸附原子对仲丁醇电催化氧化性能的影响

运用电化学循环伏安和石英晶体微天平研究了HClO4溶液中仲丁醇在Pt电极及以Sb和S吸附原子修饰的Pt(Pt/Sbad和Pt/Sad)电极上的电催化氧化过程 .从电极表面质量变化可以看出 ,仲丁醇的氧化与电极表面的氧物种有着极其密切的关系 .Pt电极表面Sb吸附原子可在较低的电位下吸附氧 ,明显提高仲丁醇的氧化活性 .与Pt电极相比 ,Sb吸附原子修饰的Pt电极使仲丁醇氧化的峰电位负移约 10 0mV .相反 ,Pt电极表面S吸附原子的氧化会消耗表面氧物种 ,抑制仲丁醇的氧化 .从电极表面质量变化提供了吸附原子电催化作用的数据

Study on Electrocatalytic Oxidation of sec-Butyl Alcohol on Pt Electrode Modified with Adatoms

The processes of adsorption and oxidation of sec butyl alcohol on Pt electrode and Pt electrodes modified with Sb and S (Pt/Sb ad and Pt/S ad ) were studied by using cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). The results demonstrated that the oxidation of sec butyl alcohol 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 sec butyl alcohol oxidation. In comparison with the case of Pt electrode, the oxidation peak potential of sec butyl alcohol on Pt surface modified with Sb was negatively shifted about 100 mV. On the contrary, the oxidation of S adatoms consumes oxygen species on Pt electrode surface. As a consequence, the oxidation of sec butyl alcohol was inhibited by the presence of S ad . The EQCM studies provided quantitative results of surface mass changes during sec butyl alcohol oxidation, and have thrown new light on elucidating different effects of adatoms Sb ad and S ad on Pt electrode towards sec butyl alcohol oxidation.