Confinement of methylammonium lead bromide nanocrystals in metal-organic frameworks as a stable scintillator for high-performance X-ray imaging

The development of perovskite nanocrystals (NCs) based composites with enhanced stability and exceptional photoelectric properties is of great significance for their application in scintillators for X-ray imaging, but it remains challenging. Herein, we demonstrate a novel and stable scintillator, achieved through a host-guest strategy involving the confinement of perovskite NCs, e.g., MAPbBr 3 NCs, in metal-organic frameworks (MOFs). The host MOF, bio-MOF-100 (denoted as bMOF), facilitates the in -situ space -confined formation of MAPbBr 3 NCs while providing quantum confinement, surface passivation, and protection to these guests. This host-guest strategy results in high exciton binding energy, bright and efficient luminescence, and significantly enhancing their stability against various factors such as air, heat, UV, solvents and X-ray irradiation. Consequently, this advancement prompts the transition of their application scenarios from the colloidal state to the solid state. The bMOF superset of MAPbBr 3 scintillator exhibits a linear response to X-ray with a detection limit determined to be 170 nGy air s -1 . Moreover, the bMOF superset of MAPbBr 3 -PMMA scintillator screen demonstrates high -quality X-ray imaging with an impressive spatial resolution of 14.7 lp mm -1 . This work provides a new avenue for the development of perovskite NCs-based host-guest composites and paves the way for the broader implementation in solid-state optoelectronic applications.