Effect of ZnI 2 cosolute on quality and performance of γ-CuI ultrafast scintillation crystal grown via evaporation method in acetonitrile solvent

Abstract γ-CuI single crystal was grown via evaporation method in ZnI 2 acetonitrile solvent. The ZnI 2 plays a unique role which can not only increase the solubility of CuI in acetonitrile but also introduce the Zn and I ions in the crystal. The γ-CuI crystal grown in ZnI 2 acetonitrile is regular and transparent. Its size reaches up to 18 × 11 × 2 mm 3 which is larger than that of the crystal grown in pure acetonitrile. In terms of the photoluminescence, the intensity of the emission at 411 nm of the crystal grown with ZnI 2 as a cosolute is much higher than that of the crystal grown without ZnI 2 , which implies that the crystallinity of the crystal can be improved by ZnI 2 doping. The X-ray excited luminescence of the crystal shows that the emission at 435 nm can be significantly enhanced and the emission near 680 nm can be suppressed by introducing Zn and I in the natural non-stoichiometry γ-CuI crystal. The nature of the phenomena is discussed. The decay time of the emission at 435 nm similar to that of the emission at 411 nm is faster than the detection limit of the instrument, i.e. less than 1 ns, and the average decay time of the emission near 680 nm is about 183 ns. The results can provide a useful guide to optimize the scintillation properties of γ-CuI single crystal.