Low-dimensional strategy of ultra-fast high-efficiency scintillators for X-ray imaging under indoor light interference†

Metal halide perovskites are emerging as promising X-ray sensitive materials. However, their practical application as scintillators is hindered by low light yield and long radiative decay times. Here, we report lead-free Bmpip₂SnBr₄:12% Cu⁺ hybrid halide single crystals. Thanks to the sensitization effect of Cu⁺ ions with strong electron–phonon coupling, the photoluminescence quantum yield was increased from 67.74% to 86.01%. In addition, the interphase arrangement of organic and inorganic monomers in the 0-dimensional quantum well structure makes it difficult to transfer charge over a long distance, in which the large exciton binding energy leads to its attenuation of only 1.47 ns. The Bmpip₂SnBr₄:12% Cu⁺ single crystals can be excited by X-rays, yielding a scintillation light output of 57 977 photons per MeV and a low detection limit of 32.59 nGyair s⁻¹. Furthermore, they demonstrate a spatial resolution of 22.8 lp mm⁻¹, which demonstrates their practical application potential in X-ray imaging under indoor optical crosstalk, characterized by high light yield, short decay time, low toxicity, and cost-effectiveness.