The Key Laboratory of Low-Carbon Chemistry & Energy Conservation of Guangdong Province, Sun Yat-sen University, Guangzhou, 510275, PR China.
Phys Chem Chem Phys. 2011 Feb 21;13(7):2667-73. doi: 10.1039/c0cp01913e. Epub 2010 Dec 8.
The adsorption and electrooxidation pathways of ethylene glycol (EG) on polycrystalline palladium surfaces have been investigated in both alkaline and acidic media by in situ FTIR spectroscopy in conjunction with cyclic voltammetry. Palladium exhibits a high electrocatalytic activity in alkaline solution with low onset oxidation potentials and high current densities, depending on the pH, as well as on the supporting electrolyte. Higher potentials are required for EG oxidation in acidic solutions, where the catalytic performance decreases with increasing the pH. The products and intermediates of EG oxidation on Pd are influenced by the pH. In alkaline media, both C(2) species (glycolate, glyoxal, glyoxylate and oxalate) and C(1) species (formate and carbonate) are formed in mutual concentrations depending on the pH. In contrast, CO(2) is selectively produced in acidic aqueous solution.
采用原位傅里叶变换红外光谱法结合循环伏安法，研究了乙二醇（EG）在碱性和酸性介质中在多晶钯表面的吸附和电氧化途径。钯在碱性溶液中表现出高电催化活性，具有低起始氧化电位和高电流密度，这取决于 pH 值以及支持电解质。在酸性溶液中，需要更高的电位才能进行 EG 氧化，并且随着 pH 值的增加，催化性能会降低。EG 在 Pd 上氧化的产物和中间体受 pH 值影响。在碱性介质中，取决于 pH 值，形成了 C(2)物种（乙醇酸、乙二醛、草酸和草酸盐）和 C(1)物种（甲酸盐和碳酸盐）的相互浓度。相比之下，在酸性水溶液中选择性地生成 CO(2)。
