Luminescence and scintillation properties of TlCdCl3:Sb crystals

• Published in: Journal of materials science. Materials in electronics Vol. 35; no. 26; p. 1743
• Main Authors: Ishida, Miyu, Watanabe, Akito, Kawamoto, Hiroki, Fujimoto, Yutaka, Asai, Keisuke
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.09.2024; Springer Nature B.V
• Subjects: Atomic properties; Characterization and Evaluation of Materials; Chemistry and Materials Science; Crystal growth; Crystal lattices; Crystals; Emission spectra; Gamma rays; Luminescence; Materials Science; Optical and Electronic Materials; Photoluminescence; Red shift; Scintillation; Scintillation counters; Solidification
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-024-13529-w

An ideal scintillator for X- and gamma-ray detection should have a high light yield and a high effective atomic number ( Z eff ). In this study, we developed undoped TlCdCl 3 crystals and TlCdCl 3 :Sb (Sb: 0.5, 1.0 and 1.5 mol%) crystals with high Z eff (TlCdCl 3 :68.7), as candidate scintillators. The crystals were grown using the self-seeding solidification method, and their photoluminescence (PL) and scintillation properties were investigated. For the undoped TlCdCl 3 crystals, emission peaks were observed at 460 nm and 485 nm in the PL and X-ray-induced radioluminescence (XRL) spectra, respectively. For the TlCdCl 3 :Sb crystals, the PL spectra showed emission peaks at 480, 480 and 500 nm, while the XRL spectra exhibited peaks at approximately 510 nm. The emission bands of the TlCdCl 3 :Sb crystals were shifted to longer wavelengths than those of the undoped TlCdCl 3 crystals. The scintillation decay time constants for the undoped TlCdCl 3 crystals were 51 and 2613 ns, whereas for the TlCdCl 3 :Sb crystals, they were in the range of 65–81 and 4550–7350 ns. These results suggest that the incorporation of Sb 3+ ions induces long components of several thousand nanoseconds. The redshift and appearance of these long components indicate that Sb 3+ ions act as new luminescence centers in the undoped TlCdCl 3 crystal. The scintillation light yield of the TlCdCl 3 :Sb 1.0 mol% crystal was measured at 10,300 photons/MeV. The doping of Sb 3+ ions into the TlCdCl 3 lattice improved the scintillation light yield by up to four times compared to the undoped TlCdCl 3 crystal.