Exciton-harvesting enabled efficient charged particle detection in zero-dimensional halides

• Published in: Light, science & applications science & applications, 2024-08, Vol.13 (1), p.190-12, Article 190
• Main Authors: Wang, Qian, Wang, Chenger, Shi, Hongliang, Chen, Jie, Yang, Junye, Beitlerova, Alena, Kucerkova, Romana, Zhou, Zhengyang, Li, Yunyun, Nikl, Martin, Sun, Xilei, OuYang, Xiaoping, Wu, Yuntao
• Format: Article
• Language: English
• Subjects: 119/118; 639/624/1075/1083; 639/624/399/1015; Charged particles; Crystals; Environmental monitoring; Ionizing radiation; Lasers; Microwaves; Optical and Electronic Materials; Optical Devices; Optics; Photonics; Photons; Physics; Physics and Astronomy; Radiation; RF and Optical Engineering; Scintillation; Single crystals
• ISSN: 2047-7538; 2095-5545; 2047-7538
• DOI: 10.1038/s41377-024-01532-z

Materials for radiation detection are critically important and urgently demanded in diverse fields, starting from fundamental scientific research to medical diagnostics, homeland security, and environmental monitoring. Low-dimensional halides (LDHs) exhibiting efficient self-trapped exciton (STE) emission with high photoluminescence quantum yield (PLQY) have recently shown a great potential as scintillators. However, an overlooked issue of exciton-exciton interaction in LDHs under ionizing radiation hinders the broadening of its radiation detection applications. Here, we demonstrate an exceptional enhancement of exciton-harvesting efficiency in zero-dimensional (0D) Cs 3 Cu 2 I 5 :Tl halide single crystals by forming strongly localized Tl-bound excitons. Because of the suppression of non-radiative exciton-exciton interaction, an excellent α/β pulse-shape-discrimination (PSD) figure-of-merit (FoM) factor of 2.64, a superior rejection ratio of 10 −9 , and a high scintillation yield of 26 000 photons MeV −1 under 5.49 MeV α-ray are achieved in Cs 3 Cu 2 I 5 :Tl single crystals, outperforming the commercial ZnS:Ag/PVT composites for charged particle detection applications. Furthermore, a radiation detector prototype based on Cs 3 Cu 2 I 5 :Tl single crystal demonstrates the capability of identifying radioactive 220 Rn gas for environmental radiation monitoring applications. We believe that the exciton-harvesting strategy proposed here can greatly boost the applications of LDHs materials. We propose and demonstrate an exciton-harvesting strategy in low-dimensional halides exposed to ionizing radiation, which enhances both scintillation efficiency and charged particle discrimination capability.