High Spatial Resolution (30 lp·mm –1 ) X-ray Imaging with Thin-Film Scintillators Based on Br-Doped CsPbBr 3 @PMMA Composite

Halide perovskites are emerging as promising scintillating materials for X-ray imaging. High-quality X-ray imaging typically requires a short scintillation decay time and high spatial resolution. Herein, a CsPbBr 3.03 @poly(methyl methacrylate) (PMMA) composite film scintillator, which, using a strategy via overdoping bromine and a polycrystal-polymer composite film preparation method, was designed to achieve fast scintillation and high-resolution X-ray imaging. Excessive doping with bromine shortens the decay time of CsPbBr 3.03 powder to a level of subnanoseconds (192.4 ps). In addition, the prepared scintillator has an exciton binding energy of up to 161.75512 ± 10.45011 meV, and exhibits not only a short scintillation decay time of 26.901 ns but also a high spatial resolution of >30 lp·mm –1 . This work provides a low-cost and efficient approach for the design of halide perovskite@organic glass composite scintillators, paving the way for the further development of high-resolution X-ray imaging scintillators.