Electrochemical Oxidation of O-Containing Substances and Energy Conversion

1.甲醇电氧化的反应机理在精确控制的条件下，研究了甲醇在铂电极上的电氧化反应动力学。在恒定的表面覆盖度的强吸附物种的塔菲尔关系表明存在两个潜在的区域，其中的主要反应路径是不同的。强吸附物种与OH（a）的表面反应在E>ca时是速率决定的。0.55 V，而甲醇的氧化吸附形成反应性中间体成为速率决定步骤在E<ca。0.55在后一个电势区域中，强吸附的物种不被氧化，因此其在表面上的积累降低了氧化吸附的速率，从而降低了总氧化速率.单晶电极的制备及其电化学行为研究了氢和氧在铂的低、高指数面上的吸附在酸、碱溶液中的电化学行为 ...更多信息 i解决办法。的功能系统地变化的表面结构和溶液的pH值，并讨论了在步骤和梯田的各个表面。对于吸附的氢，Pt（111）主要提供长程有序吸附位，Pt（100）主要提供短程有序吸附位。这些吸附的氢不参与析氢反应。反应中间体是顶部的氢原子。研究了吸附态CO的电化学行为.铂-固相萃取电极上甲醇的氧化钼修饰铂-固相萃取电极使甲醇的氧化电位降低了约10%。0.15 V（ca.反应速率提高10^2倍）。Mo（III）/ Mo（IV）的氧化还原电对在Pt电极催化活性的增强中起着关键作用。与钼和甲醇物种共吸附的电极的伏安图的扩展分析表明，在钼和甲醇物种的相等覆盖率获得最高的氧化电流。并对双功能机理进行了探讨。少

1. Reaction Mechanism of Methanol Electrooxidation The reaction kinetics for the oxidation of methanol on a platinum electrode have been examined under precisely controlled conditions. The Tafel relations at constant surface coverages of the strongly adsorbed species show the existence of two potential regions where the predominant reaction path is different. The surface reaction of the strongly adsorbed species with OH (a) is rate determining at E>ca. 0.55 V, while the oxidative adsorption of methanol to form a reactive intermediate becomes the rate-determining step at E<ca. 0.55 V. In the latter potential region, the strongly adsorbed species is not oxidized so that its accumulation on the surface decreases the rate of the oxidative adsorption and thereby the total oxidation rate.2. Preparation ofSingle Crystal Electrode and its Electrochemical Behavior The electrochemical behavior of hydrogen and oxygen adsorption on platinum low- and high-index planes was examined in acid and alkal … More i solutions. The features varied systematically with the surface structure and the pH of solution and are discussed in terms of steps and terraces of the respective surfaces. With respect to adsorbed hydrogen, Pt (111) provides mainly a long-range ordered adsorption site, Pt (100) mainly short-range ordered site, respectively. These adsorbed hydrogens do not take part in the hydrogen evolution reaction. The reaction intermediate is the on-top hydrogen atom. Electrochemical behavior of adsorbed CO is also examined.3. Methanol Oxidation at Pt-SPE Electrode Modification of Pt-SPE electrode with molybdenum reduces the oxidation potential of methanol by ca. 0.15 V (ca. 10^2 times higher reaction rate). The redox couple of Mo (III) / Mo (IV) plays a key role in the enhancement of the catalytic activity of the Pt electrode. An extended analysis of voltammograms of the electrode coadsorbed with molybdenum and methanol species showed that the highest oxidation current is obtained at an equal coverage of the molybdenum and methanol species. The bifunctional mechanism was discussed. Less