Zero-dimensional hybrid zinc halide scintillators with efficient blue light emission for X-ray imaging

Scintillators, an important component of optoelectronic materials, have been used extensively for medical imaging and security detection. Currently, most X-ray imaging scintillators rely on inorganic scintillators that use rare earths. Scintillator materials with mild growth conditions, high light yield, environmental friendliness, and low cost are still worth exploring. Here, we prepared novel zero-dimensional (0D) organic-inorganic hybrid zinc halides [C9H14N]2ZnBr4 (C9H14N+ = N-butylpyridinium bromide cation) based on pyridine quaternary ammonium salt C9H14NBr and ZnBr2. Under UV excitation, the [C9H14N]2ZnBr4 single crystal shows efficient blue light emission with the center at 426 nm, a large Stokes shift of 129 nm, and a high quantum yield of 49.95 %. In addition, the highly efficient blue emission of [C9H14N]2ZnBr4 crystals was also able to be excited by X-rays. The [C9H14N]2ZnBr4 crystal exhibited a relatively low detection limit of 4.995 μGyair s-1. X-ray imaging results based on [C9H14N]2ZnBr4 scintillation screens demonstrate high-performance X-ray imaging capabilities. According to these results, [C9H14N]2ZnBr4 crystals are promising X-ray scintillators due to their non-toxicity, excellent luminescence, and good detection performance.