钛基纳米多孔金电极对甲醛氧化的电催化活性

采用水热法制备了钛基纳米金微粒修饰电极(Au/Ti)。扫描电镜图表明纳米金颗粒粒径大约为300 nm,在钛基体表面构成三维多孔网状结构。运用循环伏安,电位阶跃和交流阻抗等电化学技术研究了碱性介质中甲醛在Au/Ti电极上的电氧化行为。循环伏安图显示,甲醛在Au/Ti上的起始氧化电位在-0.90 V左右,相对于多晶金电极提前大约0.2 V,交流阻抗测试表明,甲醛在Au/Ti电极上电氧化表现出低的电荷传递电阻。研究结果表明钛基纳米金微粒修饰电极对甲醛氧化具有良好的电催化活性。

Electrocatalytic Oxidation of Formaldehyde on a Novel Titanium-Supported Nanoporpous Gold Electrode

A novel titanium-supported gold catalyst (Au/Ti) with 3D network structure was prepared by the hydrothermal process. Electrocatalytic activity of the Au/Ti electrode towards formaldehyde oxidation was evaluated by cyclic voltammetry, chronoamperometry and electrochemical impedance spectra. It was shown from cyclic voltammograms in alkaline solutions that the oxidation current of formaldehyde on the Au/Ti was much higher than that on a polycrystalline Au, and the onset potential for formaldehyde oxidation on the Au/Ti was -0.90 V (vs Ag, AgCl). Electrochemical impedance spectra on the Au/Ti reveal that in the activation range of formaldehyde oxidation, the charge transfer resistance decreases with the increase of anodic potentials. This Au/Ti electrode exhibits stable and high electrocatalytic activity for the formaldehyde oxidation.