Integrating High-Z Thorium Nodes with AIEgens in a Metal-Organic Framework for Superior X-ray Scintillation

With the rapid progression of cutting-edge technologies, the demand for scintillator performance has become increasingly stringent, requiring enhancements across multiple dimensions, such as radioluminescence intensity, flexibility, and stability. Metal-organic frameworks (MOFs) have emerged as a promising class of materials capable of addressing these challenges through their tunable structures and their hybrid organic-inorganic nature. Here, we report the design of a thorium-based MOF scintillator, Th-TCBPE, constructed from high-atomic-number thorium nodes, and an aggregation-induced emission (AIE)-active linker (H₄TCBPE). The rigid framework effectively suppresses nonradiative decay pathways of the AIE ligand, thereby affording an exceptional photoluminescence quantum yield (PLQY) of 90.83%, far surpassing that of the free ligand (56.78%). Under X-ray excitation, Th-TCBPE achieves a remarkably low detection limit of 3.46 μGy s^-1, indicative of the outstanding sensitivity to low-dose radiation. Moreover, incorporation of Th-TCBPE into a flexible poly(dimethylsiloxane) (PDMS) matrix yielded composite films capable of high-fidelity X-ray imaging with a spatial resolution of 14.91 lp mm^-1. These results underscore the promise of heavy-metal-based MOFs as efficient, multifunctional scintillators, opening new avenues for next-generation radiation detection and high-resolution imaging technologies.