Abstract
Lead-free metal halide perovskites, such as Cs3Cu2I5, have attracted significant attention as environmental friendly alternatives to lead-based perovskites due to their excellent scintillation properties and promising applications in radiation detection. Elemental doping is a widely used strategy to tailor the structural, optical and scintillation properties of halide perovskites. In this study, Li-doped Cs3Cu2I5 single crystals were successfully synthesized at room temperature using a solvent evaporation method. The structural, compositional, optical and scintillation properties of the doped single crystal were systematically investigated. Li+ doping did not alter the crystal structure, phase, or the positions of the emission and excitation peaks. However, an increase in photoluminescence (PL) decay time was observed with Li+ doping, and a similar trend was observed in scintillation decay as well. Notably, Li+ doping led to improved scintillation performance, with the energy resolution at 662 keV improving from 5.8 % to 5.0 % and a 15 % improvement in light output. The impact of Li+ doping on the α/γ ratio and α-γ discrimination was also evaluated, revealing enhancements in both the α/γ ratio and in figure of merit (FoM). These results demonstrate the potential of low-cost, solution-grown Li-doped Cs3Cu2I5 single crystals as efficient and versatile scintillators for the detection of different kinds of radiation and discrimination applications.