Li Hongjun, Li Yi, Zhang Lin, Hu Enlai, Zhao Dian, Guo Hai, Qian Guodong
Department of Physics, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China.
Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China.
Adv Mater. 2024 Aug;36(32):e2405535. doi: 10.1002/adma.202405535. Epub 2024 Jun 17.
Thermo-responsive smart materials have aroused extensive interest due to the particular significance of temperature sensing. Although various photoluminescent materials are explored in thermal detection, it is not applicable enough in X-ray radiation environment where the accuracy and reliability will be influenced. Here, a strategy is proposed by introducing the concept of radio-luminescent functional building units (RBUs) to construct thermo-responsive lanthanide metal-organic frameworks (Ln-MOFs) scintillators for self-calibrating thermometry. The rational designs of RBUs (including organic ligand and Tb/Eu) with appropriate energy levels lead to high-performance radio-luminescence. Ln-MOFs scintillators exhibit perfect linear response to X-ray, presenting low dose rate detection limit (min ≈156.1 nGys). Self-calibrating detection based on ratiometric XEL intensities is achieved with good absolute and relative sensitivities of 6.74 and 8.1%K, respectively. High relative light yield (max ≈39000 photons MeV), imaging spatial resolution (max ≈18 lp mm), irradiation stability (intensity ≈100% at 368 K in total dose up to 215 Gy), and giant color transformation visualization benefit the applications, especially the in situ thermo-responsive X-ray imaging. Such strategy provides a promising way to develop the novel smart photonic materials with excellent scintillator performances.
由于温度传感具有特殊意义，热响应智能材料引起了广泛关注。尽管在热检测中探索了各种光致发光材料，但在X射线辐射环境中其适用性不足，在该环境中精度和可靠性会受到影响。在此，提出了一种策略，即引入放射性发光功能构建单元（RBUs）的概念，以构建用于自校准温度测量的热响应镧系金属有机框架（Ln-MOFs）闪烁体。具有适当能级的RBUs（包括有机配体和Tb/Eu）的合理设计导致了高性能的放射性发光。Ln-MOFs闪烁体对X射线表现出完美的线性响应，呈现出低剂量率检测限（最小值≈156.1 nGys）。基于比率X射线激发发光（XEL）强度的自校准检测得以实现，绝对灵敏度和相对灵敏度分别为6.74和8.1%K。高相对光产额（最大值≈39000光子/兆电子伏）、成像空间分辨率（最大值≈18线对/毫米）、辐照稳定性（在368 K下总剂量高达215 Gy时强度≈100%）以及巨大的颜色转变可视化有利于应用，特别是原位热响应X射线成像。这种策略为开发具有优异闪烁体性能的新型智能光子材料提供了一条有前景的途径。
