Preparation of Lead-free Two-dimensional Layered (C8H17NH3)2SnBr4 Perovskite Scintillators and Their Application in X-ray Imaging.

Scintillators, as spectral and energy transformers, are essential for X-ray imaging applications. However, its current disadvantages including high-temperature sintering and generation of agglomerated powders or large bulk crystals may not meet the increasing demands of low-cost, air-stability, non-toxicity and flexible radiation detection. Thus, improved perovskite scintillators are developed in this research. A hybrid perovskite ((C8H17NH3)2SnBr4) which is non-toxic, lead-free and organic-inorganic is developed as a scintillator with good emission performance, high radioluminescence (RL) intensity and low detection limit of X-ray. These perovskite scintillators are synthesized at low temperature in aqueous acid solution, through which they generate near-unity photoluminescence (PL) quantum yield of 98% with the excitation of ultraviolet. As far as we know, this work is the first to show that the two-dimensional (2D) (C8H17NH3)2SnBr4 perovskite scintillator films prepared by the coating of polymer layer can be applied to X-ray imaging system. The results demonstrate that low-cost X-ray imaging device with good resolution and performance benefits dramatically from this lead-free organic-inorganic hybrid perovskite film. Therefore, this two-dimensional (C8H17NH3)2SnBr4 perovskite scintillator may be a highly potential candidate of scintillating materials for X-ray imaging techniques.