稀土离子掺杂纳米材料的高效上转换发光与光谱调控机制研究

Upconversion luminescence based on transitions of rare earth ions has been the hotspot in the research field of materials science. The key point is to realize efficient upconversion luminescence and spectral modification in order to broaden applications of upconversion luminescent nanomaterials. Previous investigations have focused on the synthesis of luminescent nanomaterials, clarification of luminescence mechanisms and exploration of applications. It is urgent to carry out systematical studies based on ligand field theory, energy transfer principle, and defect and surface state engineering, etc., to realize the efficient upconversion luminescence and spectral modification. In this project, we aim to realize efficient upconversion luminescence and spectral modification via band engineering and design of ligand field, control of energy transfer and defect as well as surface state. We will carry out quantitative characterization on the local structures of rare earth ions and defects by using NMR, ESR and PAT. Based on the investigation on the dynamic process and energy transfer mechanism of rare earth doped nanomaterials, we will develop techniques for controlling defect and surface state, establish the quantitative relationships between structural parameters of rare earth doped nanomaterials and quantum yield of upconversion luminescence, and explore their promising applications in bioimaging and solar cell.

稀土离子掺杂纳米材料的上转换发光是当今国际材料科学研究领域的一个热点。实现高效上转换发光和光谱调控是进一步拓展上转换纳米材料应用的关键。以往的研究主要集中在纳米材料的合成、发光机理以及应用探索，迫切需要从稀土掺杂纳米材料的结构特征出发，进行系统深入的基于配位场理论、能量传递原理以及缺陷和表面态影响机制的发光机理研究，最终指导实现高效上转换发光和光谱调控。本项目将围绕实现稀土掺杂纳米材料的高效上转换发光和光谱调控，通过能带工程和配位场设计、能量传递控制以及缺陷和表面态调控实现高效的上转换发光。用核磁共振、电子顺磁共振和正电子湮没等进行稀土配位状态以及缺陷等微观结构的量化表征，用时间分辨光谱研究稀土掺杂纳米颗粒的上转换发光动力学过程和能量传递机制，开拓缺陷操控和表面修饰技术，建立稀土离子掺杂纳米颗粒的结构参数与上转换发光量子效率的定量关系，探讨在超分辨生物成像和太阳能利用等领域的应用。

稀土离子掺杂纳米材料的上转换发光是当今国际材料科学研究领域的一个前沿热点。实现高效上转换发光和光谱调控是进一步拓展上转换纳米材料应用的关键。以往的研究主要集中在纳米材料的合成、发光机理以及应用探索，需要从稀土掺杂纳米材料的结构特征出发，进行系统深入的基于配位场理论、能量传递原理以及缺陷和表面态影响机制的发光机理研究，最终指导实现高效上转换发光和光谱调控。本项目围绕实现稀土掺杂纳米材料的高效上转换发光和光谱调控，通过能带工程和配位场设计、能量传递控制以及缺陷和表面态调控实现高效的上转换发光。用核磁共振、电子顺磁共振和正电子湮没等进行了稀土配位状态以及缺陷等微观结构的量化表征，用时间分辨光谱研究了稀土掺杂纳米颗粒的上转换发光动力学过程和能量传递机制，开拓了缺陷操控和表面修饰技术，建立了稀土离子掺杂纳米颗粒的结构参数与上转换发光量子效率的定量关系，探讨了在超分辨生物成像和太阳能利用等领域的应用。在Nature Commun., Adv. Mater., J. Mater. Chem.等发表论文30余篇，在国际会议做大会特邀报告4次，国内学术会议作特邀报告6次。产生了很好的学术影响。