多酸-二氧化钛复合膜的制备及其光催化降解水中有机污染物研究

项目名称： 多酸-二氧化钛复合膜的制备及其光催化降解水中有机污染物研究

项目编号： No.50878041

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 袁星

作者单位： 东北师范大学

项目金额： 38万元

中文摘要： 采用溶胶?凝胶法结合程序升温水热技术和旋涂技术，制备出高效易回收的纳米介孔多酸/二氧化钛（H3PW12O40/TiO2）复合膜。通过优化复合膜的制备条件，获得具有优异表面物理化学性质的新型复合材料，并通过多种分析测试手段，揭示复合膜物化结构同光催化活性之间的关系。在模拟太阳光（波长范围：320 nm-680 nm）照射下，以多种典型难降解有机污染物（染料、内分泌干扰物、氯酚类等）作为目标化合物，研究所制备的H3PW12O40/TiO2复合膜光催化活性，系统研究不同反应条件对光催化降解性能的影响，建立相应的动力学模型，阐明H3PW12O40/TiO2复合膜光催化氧化作用和光催化降解有机污染物的机理。研究发现：相对于TiO2，所制备的H3PW12O40/TiO2复合膜光催化活性有了明显提高，主要是由于H3PW12O40和TiO2之间发生了协同作用，H3PW12O40接受TiO2表面的光生电子生成POM-，电子-空穴对得到有效分离，POM-和空穴进一步与水反应生成活性羟基自由基，有效降解和矿化有机污染物。本研究可为较大规模下的实际应用提供基础数据。

中文关键词： 磷钨酸；二氧化钛；复合膜；光催化；有机污染物

英文摘要： The high efficient and reused nanometer H3PW12O40/TiO2 composite films with mesoporous structure were prepared by the sol-gel combined temperature programmed hydrothemal method and spin coating technique. The novel composite films showed excellent physical and chemical properties through optimizing preparation conditions. The surface morphology of the as-prepared composite films was characterized by various analysis tests to confirm the quantity-effect relation with materialized structure and photocatalytic activity. Under simulated sunlight (wavelength extent: 320 nm-680 nm) irradiation, the photocatalytic activities of the composite films were studied via the degradation of many typical difficult degradable organic compounds (dyes, endocrine disrupters and chlorophenols). The various influences on degradation were investigated systematically, including H3PW12O40 loadings, initial concentration and solution pH and so on. Corresponding dynamic models were established and photocatalytic oxidation and photodegradation mechanisms were also discussed in depth. The research results indicated that the photocatalytic activities of as-prepared composite films was higher than pure TiO2 film. It is the synergistic action between H3PW12O40 and TiO2 that improves the efficiently degradation and mineralization of various pollutants.That is to say, POM can accept photogenerated e- of TiO2 to occur POM-, which inhibits effectively the recombination of e- - h+ and prompts POM- and h+ reacting with H2O to generate active hydroxyl radicals. The study provided the basis of data and technology reference for the elimination of the toxic and harmful substance in practical environments and related industries.

英文关键词： H3PW12O40; TiO2; composite film; photocatalytic; organic pollutant