Circularly Polarized Radioluminescence from Chiral Perovskite Scintillators for Improved X‐ray Imaging

Scintillators display radioluminescent properties when irradiated by high-energy photons and therefore play an essential role in radiation detection. The current inventory of scintillators is overwhelmingly represented by achiral structures, where the radioluminescence propagates isotropically after generation. Herein, we demonstrate that chiral perovskites of (R-3AP)PbBr₃ Cl⋅H₂ O (R-3APP) and (S-3AP)PbBr₃ Cl⋅H₂ O (S-3APP) emerge as a new type of scintillator displaying a distinct property of circularly polarized radioluminescence (CPRL). A high quantum yield of 27.6 %, high luminescence dissymmetric factors (g_lum ) of 4×10^-2 , and high X-ray absorption coefficients were observed for these compounds. As proof of concept, we fabricated a polarized scintillator pair by assembling chiral scintillator crystals, which provides a new strategy to attenuate optical crosstalk between the scintillators by precisely controlling the radioluminescence propagation and improves the X-ray imaging quality at the boundary region.