Pt-WO_3/C电极表面活化对乙二醇和CO氧化的作用

Effect of Surface Treatment on Electrocatalytic Activity of Pt-WO_3/C Electrode for Ethylene Glycol and CO Electrooxidation

用丙酮和四氢呋喃混合溶液对Pt-WO3/C电极进行表面活化处理后,乙二醇在Pt-WO3/C电极上的电催化氧化活性大幅度提高.发现无论在中性溶液中还是在酸性溶液中,表面活化处理后的Pt-WO3/C电极,乙二醇的起始氧化电位负移,氧化峰电流在酸性介质中增加到表面活化处理前的3.2倍;中性介质中增加到表面处理前的4.7倍,其主要原因是表面活化处理后,一方面增加了催化剂Pt的活性表面,另一方面也促进了电极表面吸附的CO的电氧化,减少了CO对电极表面的毒化作用.

After the Pt-WO3/C electrode was treated with mixed solvent of tetrahydrofuran and acetone, the electrocatalytic activity of the Pt-WO3/C electrode for the ethylene glycol oxidation was significantly increased. The onset potential of the ethylene glycol oxidation was shifted to the negative direction compared with that at the untreated Pt-WO3/C electrode. In the acidic solution, the peak current of the ethylene glycol oxidation at the treated Pt-WO3/C electrode was 3.2 times as large as that at the untreated Pt-WO3/C electrode. In the neutral solution, it became 4.7 times. The main reason is that the treatment can remove the impurity, such as the surfactant introduced in the preparation of the Pt-WO3/C electrode, which changes the surface structure of the electrode to a certain extent and increases the exposure surface area of Pt. In addition, the treatment of the Pt-WO3/C electrode can promote the oxidation of COad, the intermediate of the ethylene glycol oxidation, and thus, decrease the poison effect of the adsorbed CO to the electrode. The treatment method is simple and effective.