Surface Electric Dipole Moment Engineering of All‐Inorganic Transparent Solid Matrix for Information Encryption and X‐Ray Imaging

Abstract Perovskite nanocrystals (PNCs) show excellent optoelectronic performance and controlled synthesis of PNCs is arising as research hot spot recently. Transparent all‐inorganic glass matrix has been proved perfect protector of PNCs from aggregation. However, the precise precipitation of PNCs in glass with high photoluminescence quantum yield (PLQY) through a facile routing is still challenge. Here, site‐specifically crystallization of PNCs are rationally designed in all‐inorganic transparent solid matrix through surface electric dipole moment engineering, achieving exceptional PLQY (89.9%). Modifying the orientation of the surface electric dipole moment reduces the water‐induced nucleation barrier and promotes the crystallization of PNCs at the selected sites. In addition, the inherent ionic structure and low formation energy of CsPbBr 3 PNCs allow the luminescent structure to be erased by annealing and then recovered by water‐inducing. Combining the intense luminescence, high stability and completely reversable crystallization, the applications of PNCs‐glass in information encryption and reusable X‐ray dosimeter and imaging are demonstrated. The PNCs‐glass scintillation screen achieves the X‐ray imaging resolution of 17.5 lp mm −1 , which is the highest among all the PNCs based scintillation screen.