润湿性可控中空单分散TiO2-多孔碳的构建及其光催化降解典型VOCs研究

光催化氧化挥发性有机化合物（VOCs）是控制PM2.5和臭氧污染的有效途径之一。本项目旨在构建润湿性可控中空单分散TiO2-多孔碳催化剂，以期提高TiO2光催化降解典型VOCs时的抗湿性、活性和稳定性。该催化剂集成了多方面优势：中空结构有助于光能利用，TiO2单分散提高了活性位数量，与TiO2复合的多孔碳可促进VOCs的富集浓缩，进一步疏水调控则改进了催化材料的抗湿性能。通过对光催化剂组成、微结构和形貌调控，结合物理化学表征和光电性能测试，探明其理化性质与合成方法之间的关系，并明确其组成结构对光生载流子激发分离过程及VOCs吸附/降解速率的影响。参照实际光催化降解VOCs工况，探究主要操作参数特别是湿度对催化剂光催化行为的影响。最后通过前沿仪器分析和密度泛函理论研究，阐明新型催化剂光催化氧化VOCs时的微观反应动力学和强化机理。本项目可为高活性及高稳定性地光催化降解VOCs提供有益的借鉴。

Photocatalytic degradation of volatile organic compounds (VOCs) is one of the effective approaches for the control of PM2.5 and O3 pollution. This project aims to prepare hollow monodisperse TiO2/porous carbon (HMTiO2/PC) composites with adjustable wettability in an attempt to improve the moisture resistance, activity and stability of TiO2 during the photocatalytic oxidation of typical VOCs. The HMTiO2/PC integrates several advantages: the hollow structure of the catalyst facilitates the utilization of light energy; the monodispersion of TiO2 increases the number of catalytic active sites; the porous carbon combined with TiO2 promotes the enrichment of VOCs concentration, and the hydrophobic adjustment improves the moisture resistance of the catalytic material. By controlling the composition, microstructure and morphology of the photocatalyst and combining with the results of physical and chemical characterizations as well as photoelectric performance testing, the relationship between the physical-chemical properties of catalysts and the corresponding preparing methods will be explored. Moreover, the dependence of the excitation and separation of photogenerated carriers and the adsorption/degradation rates of VOCs on the composition and structure of the catalysts will be clarified. Referring to the practical conditions of VOCs treatment, the main operating variables, especially the humidity, on the photocatalytic performance of catalysts will be investigated. Finally, through advanced instrumental analysis and density functional theory study, the micro-reaction kinetics and enhanced mechanism of the novel catalysts for photocatalytic oxidation of VOCs will be illustrated. This project can provide a feasible solution for photocatalytic degradation of VOCs with high activity and stability.