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用电化学循环伏安研究了酸性介质中 4 种有机小分子伯醇(甲醇、乙醇、正丙醇和正丁醇)在 Pt 电极上吸附和氧化过程. 结果表明:这些伯醇电氧化反应活性的顺序为:甲醇、乙醇、正丙醇、正丁醇;在-0.25 V 至 0.1 V 的氢吸脱附电位区间,伯醇或其解离产物都会吸附在电极表面并且抑制氢吸脱附; 酸性介质中伯醇在 Pt 电极上的 CV曲线都有两个正向氧化峰, 但峰值大小随着分子结构不同而改变;伯醇的氧化与 Pt 表面生成不同氧物种密切相关; 伯醇的氧化要有表面吸附氧物种参与; 在 0.18~0.48 V 电位区间内, 负向电位扫描中伯醇的氧化电流明显比正向电位扫描的大, 说明这些伯醇的电氧化中都存在自毒化现象.
Electrochemical cyclic voltammetry was used to study the adsorption and oxidation of four small organic molecules (methanol, ethanol, n-propanol and n-butanol) on a Pt electrode in an acidic medium. The results showed that the electro- The order is: methanol, ethanol, n-propanol, n-butanol; at -0.25 V to 0.1 V hydrogen adsorption-desorption potential interval, the primary alcohol or its dissociation products will adsorb on the electrode surface and inhibit hydrogen adsorption and desorption; The CV curve of primary alcohol on Pt electrode has two positive oxidation peaks, but the peak size changes with the molecular structure. The oxidation of primary alcohol is closely related to the formation of different oxygen species on Pt surface. The oxidation of primary alcohol There was surface adsorption of oxygen species involved; in the potential range of 0.18 ~ 0.48 V, the oxidation potential of the primary alcohol in the negative potential scan was significantly larger than the positive potential scan, indicating that these primary alcohols are self-poisoning in the electro-oxidation phenomenon.