Scalable Fabrication of Low‐Cost, High‐Stability Copper(I) Halide Hybrid Scintillator for High‐Performance Flexible X‐Ray Imaging

Comprehensive Summary Traditional inorganic single‐crystal scintillators face several adverse conditions, such as high cost, complex process and poor flexibility. To avoid these shortcomings, in this work, the low‐cost benzyl bromide is used to efficiently synthesize the 0D organic‐inorganic hybrid copper(I) halide compound Cu 5 I 4 Br 3 (bz‐ted) 2 (Compound Y ) by the room‐temperature solution method. The yields of the ligand (95%) and the scintillator (97%) are nearly 100%, and a single‐batch production of 10.29 g is achieved, while the cost of the ligand raw material is drastically reduced. This material has an “all‐in‐one” (AIO) structure, with intramolecular π···π stacking interaction and Cu···Cu cuprophilic interactions together enhancing structural rigidity, resulting in its remarkable thermal, air, and light stability. Notably, Compound Y exhibits excellent yellow light‐emitting properties with an outstanding photoluminescent quantum yield (PLQY = 90.66%) and an ultrahigh external quantum efficiency (EQY = 81.59%), which is investigated to be the emission from the self‐trapped excitons (STEs). Moreover, it has favorable scintillation properties, with a low detection limit of 2.426 μGy air ·s −1 and a satisfactory spatial resolution of 17.7 lp·mm −1 . When blended with styrene‐ethylene‐butene‐styrene (SEBS) to fabricate the flexible scintillation screen, it can withstand 200% stretching and 0°–90° bending, with no halo distortion in imaging. This work not only promotes the commercial application of AIO‐structured materials, but also provides a new approach for the large‐scale fabrication of low‐cost and high‐performance flexible X‐ray scintillators.