Bright lead-free Cs3Cu2I5 perovskite scintillators for thermal neutron detection

Abstract

All-inorganic lead-free perovskite scintillators have attracted wide applications in X-ray imaging recently due to their low cost, high resolution, and environmental friendliness. However, their potential application in thermal neutron detection has yet to be thoroughly explored. In this article, the properties of all-inorganic perovskite Cs₃Cu₂I₅ scintillators for thermal neutron detection have been investigated. A simple synthesis process has been applied to produce Cs₃Cu₂I₅ scintillators. The as-prepared Cs₃Cu₂I₅ crystals exhibit intense blue emission with a photoluminescence quantum yield (PLQY) of 60.3%. A composite of ⁶LiF, Cs₃Cu₂I₅, and poly(methyl methacrylate) (PMMA) has been utilized for thermal neutron detection, which has a light yield of about 28 000 photons per thermal neutron, four times that of a commercial ⁶Li-glass (GS20) scintillator (7000 photons per thermal neutron). Effective neutron-gamma-pulse-discrimination has been achieved using a network-dynamics digital filter, effectively separating thermal neutrons from gamma events. Our composite scintillators have a high thermal neutron absorption efficiency of about 60%. In addition, Cs₃Cu₂I₅ crystals are more sensitive to X-ray irradiation compared to commercial Na-doped CsI scintillators. Our work provides a new strategy for large-scale perovskite-based thermal neutron detection and imaging.