利用晶格失配应力窄化带隙的新型纳米复合光催化剂的开发及光催化性能研究

半导体光催化技术在利用太阳能降解有机污染物和分解水制氢方面显示出巨大的应用前景，被誉为是解决环境污染和能源危机问题的一种理想"绿色技术"。窄化半导体光催化剂的带隙对拓展其光响应波长范围、提高可见光催化活性、推动光催化技术的工业化应用具有重要意义。本项目以MgO、SiO2、LaAlO3和SrFeO3为内核相，以钛氧化物光催化剂TiO2、SrTiO3和BaTiO3为壳层相，采用聚丙烯酰胺凝胶法制备核/壳型纳米复合颗粒，利用两相之间的晶格失配应力调控光催化剂的晶格参数，以窄化其带隙，实现拓展光催化剂的光响应波长范围、提高可见光催化活性。研究材料的可控制备，系统地研究材料的晶体结构、显微结构、电子结构、晶格失配应力、带隙及光催化降解有机污染物和分解水制氢的综合光催化性能，寻找材料的制备、结构、光催化性能之间的内在关联机制，开发出高效可见光响应的新型纳米复合光催化材料。

Semiconductor-based photocatalysis holds great promise for applications in decomposition of organic pollutants and water-splitting to produce hydrogen with solar energy, and is regarded to be a green technology for solving environmental and energy problems. Narrowing the bandgap of semiconductors has an important significance to extend their light-responsive range, improve their visible-light photocatalytic activity, and promote the industrial applications of photocatalytic technology. In this project, a polyacrylamide gel route is used to fabricate core/shell structured nanocomposite photocatalysts, where the core phase chosen is MgO、SiO2、LaAlO3 and SrFeO3, and the shell phase is titanium oxide photocatalysts TiO2、SrTiO3 and BaTiO3. The main aim is to narrow the bandgap, extend the light-responsive range and hence improve the visible-light photocatalytic activity of the photocatalysts through tailoring their lattice parameters using the lattice mismatch stress between core/shell phases. We will study the controllable fabrication, crystal structures, microstructures, electronic structures, lattice mismatch stress, energy bandgaps, and photocatalytic properties for decomposing organic pollutants and water splitting into hydrogen, and explore the intrinsic relationship between fabrication, structures and photocatalytic properties of materials. Based on the project research, we expect to develop advanced nanocomposite photocatalysts with high visible-light response.