研究業績

We evaluated photoluminescence and radiation response properties of organic–inorganic perovskite-type compounds with various hydroxyl alkyl amines or alkyl ether amines (HOCnH2nNH3)2PbCl4 (n = 2: C2–OH, n = 3: C3–OH, n = 4: C4–OH), (CH3CH2OCnH2nNH3)2PbCl4 (n = 2: 2-Ethoxy, n = 3: 3-Ethoxy), and (CH3C2H4OC3H6NH3)2PbCl4 (3-Butoxy). A clear broadband emission peak attributed to self-trapped excitons (STEs) was detected from the C2–OH, C3–OH, and 2-Ethoxy crystals under 310 nm excitation light. Additionally, they showed a fast decay time of 3.5 ns (C2–OH), 5.5 ns (C3–OH), and 3.0 ns (2-Ethoxy), which was ascribed to the recombination of STEs. In the scintillation spectra, the C2–OH, C3–OH, and 2-Ethoxy crystals exhibited a broad emission originating from the recombination to STEs. Furthermore, they exhibited a fast scintillation decay time of 2.2 ns (C2–OH), 3.5 ns (C3–OH), and 1.1 ns (2-Ethoxy) due to the recombination of STEs. Moreover, the light yield of the C3–OH crystal under alpha-ray was the highest, and the yield was estimated to be 1100 photons/5.5 MeV-α, which was higher than that of a ZnO single crystal.