Scintillation Properties of CsCu₂I₃ Perovskite Single Crystal Grown by Room Temperature Solution Processing Method

Metal halide perovskites have received great interest in developing scintillator materials. Among various types of perovskites, low dimensional metal halide perovskites have high exciton binding energy and Photo-Luminescence Quantum Yield (PLQY), making them suitable for X-ray and γ-ray detection. In the present work, we report the growth and characterization (structural and optical) of one-dimensional (1D) CsCu<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>I<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> single crystal (SC). The SC was grown using the solvent evaporation method at room temperature. The crystal exhibits an orthorhombic structure with <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Cmcm</i> space group. The optical characterizations show a yellow photoluminescence (PL) with large Stoke’s shift (∼ 230 nm) that originate from self-trapped exciton emission. The X-ray photoelectron spectroscopy results indicate that the addition of oleic acid prevents the oxidation of Cu+. Further, we coupled the SC with a Silicon photomultiplier (SiPM) to study the scintillation properties. The grown crystal has been characterized for light output, energy resolution, linearity, and non-proportionality. The CsCu<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>I<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> SC grown for this study exhibits a comparable light output of ∼ 20,000 ph/MeV to those grown using Inverse Temperature Crystallization (ITC), as reported in the literature. However, the energy resolution reported in the present study (11.57% at 662 keV) is better than the values reported for ITC-grown crystals in the literature. GEANT4 simulation toolkit has been used to perform the simulations, and the simulated intrinsic photopeak efficiencies for different volumes of CsCu<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>I<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> scintllator have been obtained and compared with NaI:Tl and BGO scintillators.