可见光催化耦合强化热催化净化VOCs体系的构建

VOCs are important air pollutants, and catalytic oxidation of VOCs to harmless CO2 and H2O is an efficient removal route. In consideration with the high energy consumption of the traditional thermal catalysis and the low efficiency of the photo catalysis during the purification of VOCs, this project intends to enhance the efficiency of the catalytic VOCs removal under low precious metal content and relatively mild conditions by means of visible light catalytic coupling with the thermal catalytic purification of VOCs. Understanding the synergistic catalytic mechanism and the construction of highly efficient catalytic materials with the synergistic function of light and heat are the key points for this novel process. Based on the influence factors that relate to the photo-thermal catalytic performance of the catalysts for VOCs oxidation, such as the transfer properties of the reactants and the photo induced charges, the light response range, the interaction between the active component and support etc, this work plans to design and construct monolith-like SrTiO3 nanotubes supported noble metal catalysts with photo-thermal catalytic properties. Meanwhile, the cognition of the synergy mechanism in the visible light photocatalysis promoted thermal catalytic VOCs purification system and its intrinsic relationship with the catalyst microstructure, composition, surface chemical state and catalytic properties of the photo-thermal materials is focused based on the multi-work on the micro-meso structure characterization of the catalyst, in situ characterization techniques and quantitative calculation.

VOCs是一类重要的空气污染物，催化氧化技术是有效的治理方式之一。针对传统的热催化技术的高能耗和光催化净化VOCs技术的低效率问题，本项目拟通过可见光催化耦合强化热催化净化VOCs体系的构建，实现在低贵金属含量和相对温和条件下催化净化VOCs的高效性。认知光热协同作用机制和构筑高效光热协同作用催化材料是该项技术发展的核心。项目基于影响光热协同催化净化VOCs的关键材料性能特征：反应组分和光生电荷的传递性能、材料的光响应范围和光生电荷分离、贵金属活性组分与载体之间相互作用等，进行基于钙钛矿结构SrTiO3纳米管负载贵金属的类整体式光热协同催化材料的设计和构筑。同时，结合催化剂微介观结构的系统表征、反应过程原位表征技术和量化计算，认知可见光催化耦合强化热催化剂氧化VOCs反应的协同作用机制与催化剂表界面微观结构、组成、化学态和催化性能的本质关系。

项目拟通过可见光催化耦合强化热催化净化VOCs体系的构建，实现在低贵金属含量和相对温和条件下催化净化VOCs的高效性。项目组按照项目进度表积极认真地开展研究工作，已完成各项预定目标：(1) 构筑了钛酸锶等钙钛矿直接负载金属型、异质结型和类整体纳米管阵列结构型等系列具有光热协同催化性能的催化材料；(2) 构建了可见光催化耦合强化热催化净化VOCs体系，利用低负载量的Pt、Ag等金属和半导体氧化物所构筑的光热协同催化材料，实现在不高于90 oC和可见光照条件下甲苯等难降解VOCs的高效净化；(3)通过系统表征和分析发现，在光热催化反应体系中，利用光引发所产生的单电荷活性含氧基团和热活化所产生的双电荷活性氧的协同作用，以及热作用对电荷传递的促进作用，显著提升了活性氧物种的生成和氧化能力，是实现在温和反应条件和低贵金属含量下VOCs催化净化高效性的关键。在本领域重要的学术期刊上发表论文20篇、申请发明专利7件、授权发明专利1件。项目研究结果可为高效光热协同催化净化VOCs催化材料和过程的设计与推广应用提供基础数据和参考。