In recent years, low-dimensional metal halide perovskites/quasi-perovskites with high photoluminescence quantum yield have shown potential application prospects in nuclear radiation detection. In this paper, centimeter- sized zero-dimensional perovskite Cs₃Cu₂I₅ single crystals with high optical quality was grown by the anti solvent diffusion method. The optical absorption, transmittance photoluminescence excitation (PLE) and emission (PL), time-resolved photoluminescence, X-ray excited radioluminescence (XEL), afterglow, thermoluminescence (TL) and γ-ray detection performance of Cs₃Cu₂I₅ single crystals were comprehensively investigated. The optical bandgap of as-prepared Cs₃Cu₂I₅ single crystals is 3.68 eV. Under the excitation of X-ray, Cs₃Cu₂I₅ single crystals show blue emission peaking at 448 nm originated from self-trapped exciton emission, and the principal scintillation decay time is 947 ns (96%). The afterglow level of Cs₃Cu₂I₅ single crystals is comparable to that of commercial BGO crystal. In addition, Cs₃Cu₂I₅ single crystals exhibit a high light yield of 29000 photons/MeV as γ-ray scintillators, and their scintillation properties are comparable to that of Cs₃Cu₂I₅ single crystals prepared by the melt growth method. Therefore, this work demonstrates the feasibility of low-cost crystal growth of high-performance Cs₃Cu₂I₅ single crystals.