TiO_2纳米多孔膜电极对甲醇的光电催化氧化

TiO_2 Nanometer Thin Film Electrodes for Photo electric Catalytic Oxidation of Methanol

研究了在一定光强下 ,一定粒径的TiO2 纳米多孔膜电极的厚度与光电氧化甲醇的稳态光电流的关系。认为由于TiO2 纳米多孔膜电极对OH- 的吸附 ,使甲醇和甲醛在TiO2 纳米多孔膜电极上不能形成有效的吸附是影响彻底氧化甲醇的关键。讨论了体系中OH- 的浓度对氧化甲醇的影响 ,发现在碱性环境中氧化甲醇比在酸性环境中有利得多 ,这可能与OH- 在TiO2 纳米多孔膜电极上的吸附有关。同时 ,研究发现OH- 在TiO2 表面的吸附规律符合朗格缪尔 (Langmuir)

The dependence of photo electric catalytic oxidation current on the thickness of porous TiO 2 nanometer thin film electrodes is investigated under constant illumination.It is believed that as adsorption of TiO 2 surface to OH - is stronger than that to CH 3OH and CH 2O,CH 3OH can not be oxidated utterly.Reasons why the oxidation of methanol is easier in alkaline than in acid solution may be that the oxidation of methanol is determined by chemisorption of OH - on TiO 2 electrode surface.In addition,the adsorbent rule of OH - on TiO 2 electrode surface corresponds to equation of Langmuir equal temperature adsorption.