Solution‐Processable Copper Iodide Scintillator for High‐Resolution Planar‐Curved X‐Ray Imaging

The development of high‐performance scintillators is crucial for advancing radiation detection and X‐ray imaging technologies. Herein, we report the rational design and synthesis of a 0D hybrid copper iodide scintillator (CyclamH 4 )Cu 2 I 6 , which exhibits intense radioluminescence centered at 450 nm. This blue emission demonstrates excellent spectral match with the peak photon detection efficiency of modern silicon photomultipliers, thereby facilitating efficient photodetection. The (CyclamH 4 )Cu 2 I 6 scintillator achieves a high light yield of 42 720 photons/MeV, a detection limit of 83.5 nGy air s −1 , and notable radiation resistance stability. Accordingly, the inch‐size flexible (CyclamH 4 )Cu 2 I 6 @PDMS scintillator film achieves superior performance in X‐ray imaging, as evidenced by a high spatial resolution of 13.6 lp/mm. This work validates copper halides as a tunable platform for the design of scintillators, thereby opening new avenues for the innovation of X‐ray imaging technology.