Ionothermal synthesis of a hybrid cuprous(I) iodide scintillator with efficient cyan emission and high antiwater stability

Abstract

Hybrid Cu(I)-based halides have been widely studied in the field of optoelectronics due to their outstanding optical properties as well as their remarkable structural diversity, however, the complicated synthetic method and poor stability hampered Cu(I)-based metal halides practical applications. Herein, a new zero-dimensional (0-D) hybrid copper iodide (Cu₂I₂(3,4-DMP)₄ (1, 3,4-DMP = 3,4-Dimethylpyridine) has been synthesized by ionothermal reaction. Under UV irradiation, 1 shows cyan emission with photoluminescence quantum yields (PLQY) as high as 80.07 %. In addition, 1 exhibits high antiwater stability, the photoluminescence (PL) and the radioluminescence (RL) intensity of 1 both above 80 % of the original ones when stored in water for 90 days. At room temperature, 1 shows an effective light yield of 38,031 photons/MeV and a sensitive X-ray response, with a detection limit as low as 106.71 nGy/s, significantly below the dose required for medical diagnostics (5.5 μGy/s). Based on the above excellent performance, (Cu₂I₂(3,4-DMP)₄ can be used as fluorescent inks for aerosol jet printing (AJP). This study provides a new avenue for designing multifunctional materials and application of non-toxic hybrid metal halides.