Near-unity broadband emissive hybrid manganese bromides as highly-efficient radiation scintillators

Abstract

Zero-dimensional (0D) hybrid manganese halides have gained wide attention for the various crystal structures, excellent optical performance and scintillation properties compared with 3D lead halide perovskite nanocrystals. In this work, a new family of 0D hybrid manganese halides of A₂MnBr₄ (A = BzTPP, Br-BzTPP, and F-BzTPP) based on discrete [MnBr₄]²⁻ tetrahedral units is reported as highly efficient lead-free scintillators. Excited by UV or blue light, these hybrids emit bright green light originating from the d–d transition of Mn²⁺ with near-unity PLQY (99.5%). Significantly, high PLQY and low self-absorption render extraordinary radioluminescence properties with the highest light yield of 80,100 photons MeV⁻¹, which reached the climax of present hybrid manganese halides and surpassed most commercial scintillators. The radioluminescence intensity features a linear response to X-ray doses with a detection limit of 30 nGy_air s⁻¹, far lower than the requirement of medical diagnostic (5.5 µGy_air s⁻¹). X-ray imaging demonstrates ultrahigh spatial resolution of 14.06 lp mm⁻¹ and short afterglow of 0.3 ms showcasing promising application prospects in radiography. Overall, we demonstrated new hybrid manganese halides as promising scintillators for advanced applications in X-ray imaging with multiple superiorities of nontoxicity, facile-assembly process, high irradiation light yield, excellent resolution, and stability.