Band Alignment Engineering in ns2 Electrons Doped Metal Halide Perovskites

Luminescent metal halide perovskites (MHPs) open new avenues for highly efficient radiation detection. To challenge the state-of-art technology, fundamental understanding of factors controlling radiation light yield of MHP scintillators is urgent. Herein, a design method is established by simultaneously considering charge-transfer and recombination efficiencies via band alignment engineering in doped MHPs materials, and this strategy is corroborated experimentally and computationally by applying it to the luminescence of ns(2) electron (Sb3+, Bi3+, and Te4+) doped vacancy-ordered double perovskite Cs2ZrCl6. Alloying Te4+ into Cs2ZrCl6 is optimized and significantly improves the scintillation performance, including a twofold increase in light yield and a threefold increase in detection limit over pristine Cs2ZrCl6, and high-resolution X-ray imaging with 20 mu m for 2D and 0.2 mm for 3D imaging. It is believed that doping engineering in MHPs enabling band alignment method holds great potential for the development of next-generation MHP scintillators.