NaYF4:RE/多重氧空位调制的半导体复合中空纳米纤维构筑及光学性质研究

针对TiO2光吸收范围窄、光生载流子易复合以及表面活性位点有限等问题，本项目拟采用静电纺丝技术结合一步还原方法构筑NaYF4:RE/多重氧空位调制的半导体复合中空纳米纤维，利用NaFY4:RE上转换发光特性及氧空位调制的MO3-x (M=W, Mo)表面等离激元共振效应实现紫外-近红外超宽光谱吸收，并协同增强黑TiO2的光利用效率；通过精确控制异质界面处的能带结构及光生载流子的转移过程，为MO3-x提供电子使其保持表面等离激元特性，同时抑制黑TiO2光生载流子复合；调控一维纳米纤维中空结构增加材料表面活性位点，优化径向电子转移路径，提高载流子分离效率，结合理论模拟揭示材料结构与光学性能之间的构效关系，获得光利用率高、光量子效率高、稳定性高的稀土上转换-非化学计量比半导体复合纳米纤维，为建立与发展全光谱吸收的光电功能材料提供新思路。

Aiming at solving the issues of narrow light absorption range, low quantum efficiency and limited surface active sites for TiO2-based photocatalysts, this project proposed mainly focuses on constructing NaFY4:RE/multiple oxygen vacancy controlled semiconductor based composite hollow nanofibers by combining electrospinning technology and one-step reduction method. The effects of up-conversion luminescence of NaFY4:RE and oxygen vacancy controlled Surface Plasmon Resonance (SPR) of MO3-x (M=W, Mo) can achieve the super-wide absorption region from UV to near infrared region, hence synergistically enhancing the light efficiency of for black-TiO2. Adjusting the transfer process of internal photo-generated carrier occurred at heterojunction interface can release electrons for MO3-x to keep the SPR property, effectively inhabiting the recombination of photo-generated carrier of black-TiO2. Constructing 1D hollow nanostructure can greatly improve the surface catalytic active sites which can guarantee electron transfer along with radial direction pathways, increasing the separate efficiency of photo-generated carrier, combining the assistant experiment, further illustrating the structure-activity relationship between the as-designed material architecture and light property, finally obtaining rare earth up-conversion/non-stoichiometry semiconductor based hollow composite nanofibers with the favorable properties of high light efficiency, high quantum efficiency and high structural stability, which provides a new approach for constructing and developing novel and low-cost non-mental photocatalysts with wide absorption spectrum.