A Universal Doping Strategy for Boosting Luminescence Efficiency of Blue‐Emitting Hybrid Zn Halides as Ultrastable and Underwater Scintillators

ABSTRACT Underwater blue‐emitting X‐ray scintillator is important for the resource exploration and communication in deep sea, but remains a significant challenge for perovskites. Herein, we proposed a universal Pb 2+ ‐doping strategy toward a family of stable 0D Zn halide A n ZnBr 4 realizing highly efficient blue‐emitting scintillation. First‐principles calculations indicate that doped‐Pb 2+ introduced extremely narrow impurity bands, which prompt more carriers into conduction bands, leading to near‐unity PLQY. Meanwhile, these halides can withstand complex aqueous solutions containing various chemical substances in wide pH range (1–14) demonstrating ultrahigh water‐resistance stabilities. More significantly, these halides exhibit satisfactory scintillation and imaging performance with highest light yield (31,500 photons MeV −1 ), low detection limit (141.2 n Gy air s −1 ) and large spatial resolution (15.10 lp/mm), ranking among the top‐performing Zn halide scintillators reported to date. The high water‐resistance stabilities and satisfactory scintillation performance endow these halides advanced underwater X‐ray imaging. This work not only provides a universal strategy to explore highly‐efficient blue‐emitting perovskite scintillators, but also realizes application of high‐resolution X‐ray imaging in underwater environment.