面向含水环境应用的ABF4基分层化合物的合成化学及高效能量转化研究

常用敏化剂Yb3+与水分子在近红外区存在光吸收重叠，造成严重能量损失，制约许多光功能材料在能源及环境等含水环境的应用。在文献调研和前期研究基础上，我们设想把ABF4基化合物的分层构筑，界面应力调控和Nd3+-Yb3+协同敏化相结合，获得808 nm激发单波段发射的稀土上转换发光材料，降低近红外光引起的热效应和能量损失。为此，本项目拟通过Er3+/Tm3+/Ho3+分层掺杂ABF4的合成，Nd3+-Yb3+协同敏化，非本征能级构建、晶格应力调变带隙宽度和晶格对称性等方式，合成Nd3+-Yb3+协同敏化上转换材料-半导体复合材料；利用传统光功能材料无法利用的近红外光，拓宽其在近红外区的响应范围，在提高上转换荧光探测深度的同时，实现紫外-可见-近红外光区全光谱响应，探索抑制红外光在水反应体系中热效应的新途径，实现面向含水环境光化学反应中的高效能量转化，为未来能源及环境等领域应用提供高性能新材料。

The overlapping of absorption spectra between commonly used sensitizer Yb3+ and water molecules in the near infrared region results in a profound loss of energy, which would constrain the applications of many photo-functioned materials in energy conversion and environmental applications, especially in water containing condition. Based on the literature reports and our previous studies, we proposed to construct ABF4-based multi-layer structures in consideration of the interfacial stress regulation and synergistic sensitization of Nd3+-Yb3+, could highly possible to realize single band up-conversion emission with 808nm excitation, and further to significantly reduce the thermal effect caused by near-infrared light. Motivated by this, in this project, we will prepare Nd3+ -Yb3+ co-sensitized up-conversion materials firstly, and then aim to synthesize Er3+ /Tm3+/Ho3+ doped ABF4-MOx multi-layer composites. We will study the effect of Nd3+-Yb3+ co-sensitization, non-intrinsic level construction, modulation of lattice stress in band gap width of MOx as well as lattice symmetry of each component. We expect to utilize the near infrared light, that traditional photo-function materials could not be excited, to broaden the light response range. Moreover, the realization of full spectral response from UV, visible to near infrared lights can increase the detection depth of up-conversion fluorescence, and help us develop new ways to suppress the thermal effect of infrared light in watery photochemical reaction. We believe that these achievements could lead to new materials of high performance for further applications in energy conversion and environmental fields.