Modified luminescent properties from green afterglow to efficient orange emission in zirconium-based organometallic chloride scintillator by Sb3+ doping

Zero-dimension (0D) metal halides based on metals with the 5s2 lone pair have attracted great attentions due to their strong triplet broadband emission. However, the conversion from weak afterglow to efficient and fast photoluminescence by regulating the composition of 0D metal halides is still a tough challenge. Herein, Sb3+ ions-doped 0D (Ph4P)2ZrCl6·4CH3CN metal halides were synthesized by a simple solution crystallization method. Compared with the weak triplet green 560 nm afterglow from the organic Ph4P+ components, the emission of the Sb3+-doped material exhibits a strong orange photoluminescence at 660 nm with a high photoluminescence quantum yield of 72% by a host to dopant energy transfer process. In addition, a flexible large-sized X-ray scintillator screen with an area of 16 cm2 was prepared using polydimethylsiloxane as the host matrix, which exhibits excellent scintillation properties with light yields of 8,290 photons/MeV, low detectable limits of 0.986 μGy/s, and a near-infrared broadband emission from 600 nm to 850 nm under steady-state X-ray excitation, which is highly compatible with the response range of the long-wave sensitive silicon-based photodetectors. Therefore, this work not only provides a deep insight into the energy transfer process in the 0D metal halide materials but also opens an alternative approach to realize flexible large-size near-infrared X-ray imaging based on the 0D metal halide scintillator.