You Xinyu, Han Jiaxing, Del Colle Vinicius, Xu Yuqiang, Chang Yannan, Sun Xiao, Wang Guichang, Ji Chen, Pan Changwei, Zhang Jiujun, Gao Qingyu
College of Chemical Engineering, China University of Mining and Technology, 221116, Xuzhou, People's Republic of China.
Department of Chemistry, Federal University of Alagoas-Campus Arapiraca, Av. Manoel Severino Barbosa s/n, Arapiraca, AL, 57309-005, Brazil.
Commun Chem. 2023 May 29;6(1):101. doi: 10.1038/s42004-023-00908-3.
Water and its dissociated species at the solid‒liquid interface play critical roles in catalytic science; e.g., functions of oxygen species from water dissociation are gradually being recognized. Herein, the relationship between oxide identity (PtOH, PtO, and PtO) and electrocatalytic activity of platinum for ethanol electrooxidation was obtained in perchlorate acidic solution over a wide potential range with an upper potential of 1.5 V (reversible hydrogen electrode, RHE). PtOH and α-PtO, rather than PtO, act as catalytic centers promoting ethanol electrooxidation. This relationship was corroborated on Pt(111), Pt(110), and Pt(100) electrodes, respectively. A reaction mechanism of ethanol electrooxidation was developed with DFT calculations, in which platinum oxides-mediated dehydrogenation and hydrated reaction intermediate, geminal diol, can perfectly explain experimental results, including pH dependence of product selectivity and more active α-PtO than PtOH. This work can be generalized to the oxidation of other substances on other metal/alloy electrodes in energy conversion and electrochemical syntheses.
水及其在固液界面的解离物种在催化科学中起着关键作用；例如，水离解产生的氧物种的功能正逐渐被认识到。在此，在高氯酸酸性溶液中，在高达1.5 V（可逆氢电极，RHE）的宽电位范围内，获得了氧化物形态（PtOH、PtO和PtO）与铂对乙醇电氧化的电催化活性之间的关系。PtOH和α-PtO而非PtO作为促进乙醇电氧化的催化中心。这种关系分别在Pt(111)、Pt(110)和Pt(100)电极上得到了证实。通过密度泛函理论（DFT）计算建立了乙醇电氧化的反应机理，其中铂氧化物介导的脱氢和水合反应中间体偕二醇能够完美解释实验结果，包括产物选择性的pH依赖性以及α-PtO比PtOH更具活性。这项工作可推广到能量转换和电化学合成中其他金属/合金电极上其他物质的氧化。
