2D Perovskite Mn²⁺-Doped Cs₂CdBr₂Cl₂ Scintillator for Low-Dose High-Resolution X-ray Imaging

High-performance X-ray scintillators with low detection limits and high light yield are of great importance and are a challenge for low-dose X-ray imaging in medical diagnosis and industrial detection. In this work, the synthesis of a new 2D perovskite, Cs2CdBr2Cl2, via hydrothermal reaction is reported. By doping Mn2+ into the perovskite, a yellow emission located at 593 nm is obtained, and the photoluminescence quantum yield (PLQY) of Cs2CdBr2Cl2:5%Mn2+ perovskite reaches the highest value of 98.52%. The near-unity PLQY and negligible self-absorption of Cs2CdBr2Cl2:5%Mn2+ enable excellent X-ray scintillation performance with a high light yield of 64 950 photons MeV-1 and low detection limit of 17.82 nGy(air) s(-1). Moreover, combining Cs2CdBr2Cl2:5%Mn2+ with poly(dimethylsiloxane) to fabricate a flexible scintillator screen achieves low-dose X-ray imaging with a high resolution of 12.3 line pairs (lp) mm(-1). The results suggest that Cs2CdBr2Cl2:5%Mn2+ is a promising candidate for low-dose and high-resolution X-ray imaging. The study presents a new approach to designing high-performance scintillators through metal-ion doping.