高活性Ti基纳米TiO_2膜催化电极的制备

Preparation of Ti-Based Nanocrystalline TiO_2 Film Electrode with High Activity

采用“牺牲阳极法”恒槽压电解含有 0 .0 0 5mol·L- 1四乙基溴化铵的乙醇溶液 ,加入微量乙酰丙酮作稳定剂 ,电合成TiO2 前驱体钛酸乙酯Ti(EtO) 4 ,经水解、涂膜、煅烧制备Ti基纳米TiO2 膜电极 (Ti/nano_TiO2 ) .TEM、SEM、XRD测试表明 :TiO2 颗粒尺寸在 10～ 35nm ,膜厚达 0 .5μm ,主要为锐钛矿晶型 ,膜为多孔三维网状结构 .循环伏安法研究了纳米TiO2 膜电极对草酸还原为乙醛酸、硝基苯还原为对氨基苯酚反应的电催化活性 ,结果发现纳米膜中的Ti(Ⅳ ) /Ti(Ⅲ )氧化还原电对起一种中介作用 ,可使有机物如草酸和硝基苯间接电还原 ,且电极催化活性高 。

The potentiostatic electrosynthesis of Ti(EtO) 4 was studied by anodic dissolution of metal titanium(TA1) in solution of 0.005 mol·L -1 (EtO) 4NBr in the ethanol (AR) in the presence negligible CH 3COCH 2COCH 3.The Ti_based nanocrystalline TiO 2 Film electrode (Ti/nano_TiO 2) was prepared by sol_gel method.By TEM,SEM and XRD,it has been shown that the anatase particle of TiO 2 was 10～35 nm in diameter and the film was 0.5 μm in thickness.The nanocrystalline film was composed of a three_diminsional network of interconnected particles.Reodx behavior and electrocatalytic activities of the Ti/nano_TiO 2 electrode were investigated by cyclic voltammetry (CV) from oxalic acid and nitrobenzene to glyoxalic acid and p_aminionphenol. The Ti(Ⅳ)/Ti(Ⅲ) redox system,as a medium,shows highly electrocatalytic activities and stable characteristic to indirect electroreduction of organic compounds(e.g.:oxalic acid and nitrobenzene).