X-Ray Quantum Cutting Scintillator Based on CsPbCl_xBr_3-x:Yb^{3+ Single Crystals}

Metal-halide perovskites, especially for 3D halide perovskite single crystals (SCs), are emerging as the promising scintillators. However, the strong self-absorption and low light yield of these perovskites restrict their practical applications. Quantum cutting can convert a high energy photon into multiple low energy photons, endowing a large Stokes shift and high photoluminescent quantum yield (PLQY). Here, this work reports a novel quantum cutting material, CsPbClxBr3-x:Yb3+ perovskite SCs, with the PLQY of 149% and a Stokes shift >550 nm, successfully conquering the issues of poor PLQY induced by the thermal quenching and the large self-absorption in perovskite SCs. Benefiting from the extremely high PLQY and negligible self-absorption effect, the first high-performance quantum cutting scintillators based on CsPbClxBr3-x:Yb3+ perovskite SCs are developed, exhibiting high transmittance, large X-ray absorption/conversion efficiency, outstanding light yield of approximate to 1.12 x 10(5) photons MeV-1, and a detection limit as low as 176.5 nGy(air) s(-1). Finally, a single-pixel X-ray imaging is achieved by integrating CsPbCl3:Yb3+ SCs with silicon photomultiplier. This work sheds light on exploring highly competitive scintillators beyond the scope of traditional perovskites.