金属氧化物团簇修饰二氧化钛可见光下高效净化室内污染物的研究

Indoor air purification is a hot topic in the field of environmental catalysis. TiO2 Photocatalytic oxidation has broad application prospects in purifying indoor air. At present, TiO2 can only be excited under UV light, and cannot be widely used in indoor environment. Therefore, it is urgent to modify TiO2 to achieve efficient purification of indoor pollutants under visible light. When TiO2 is modified by metal oxide clusters (MOx), the catalysts have the visible light response, at the same time, the separation efficiency of electrons and holes is also improved due to the interfacial charge transfer (IFCT) process. However, the mechanism of IFCT is still controversial. In this study, a serials of catalysts are synthesized in which the interaction between MOx and TiO2 are different. Then we focus on the effect of the interaction between MOx and TiO2 on the mechanism of IFCT. Using formaldehyde, benzene series, and ammonia as probes, the relationship between the mechanism of IFCT on MOx/TiO2 and photocatalytic activity is clarified, and this study will provide theoretical guidance for photocatalytic elimination of indoor air pollutants.

室内空气净化是目前环境催化领域的研究热点，TiO2光催化技术用于净化室内空气具有广阔的应用前景。目前TiO2受限于在紫外光照下才可激发，无法在室内环境广泛应用，因而亟需改性TiO2实现可见光下高效净化室内污染物。金属氧化物团簇（MOx）修饰TiO2不仅能产生对可见光的响应，而且由于发生界面电荷转移，电子和空穴的分离效率也得以提高，但是界面电荷转移的机理还存在较大争议。本项目拟定向设计不同相互作用的MOx/TiO2催化剂体系，研究MOx与TiO2的相互作用强弱对界面电荷转移机理的影响，以室内空气污染物甲醛、苯系物、氨气等为探针，阐明MOx/TiO2界面电荷转移机理与光催化反应活性的因果关系，为光催化净化室内空气提供理论基础。

室内空气净化是目前环境催化领域的研究热点，TiO2光催化技术用于净化室内空气具有广阔的应用前景。目前TiO2受限于在紫外光照下才可激发，无法在室内环境广泛应用，因而亟需改性TiO2实现可见光下高效净化室内污染物。在本项目资助下，进行了可见光下光催化氧化NH3的研究，发现Ag3PO4具有优异的可见光催化氧化NH3的活性。通过各种表征手段，阐述了Ag3PO4可见光下催化氧化NH3的机理。另外，开展了Cu-TiO2可见光下光催化氧化HCHO的研究，证明了甲酸盐的分解是整个反应的速控步，并且证明‧OH物种而不是‧O2-物种在甲酸盐的分解过程发挥了主要作用。最后开展了CuOx-TiO2光催化氧化NH3的研究，将CuOx负载于锐钛矿相和金红石相的TiO2,通过各种表征手段，阐明了CuOx/TiO2可见光下光生电子和空穴转移的机理。本项目取得的研究进展可为指导光催化净化室内空气提供一定的理论基础。