Suppressed Concentration Quenching Via Divalent Eu/Sr Alloying in Hybrid Iodides Scintillators Toward Bright Luminescence for X‐ray Imaging
Abstract
Abstract Overcoming concentration quenching in rare‐earth‐activated luminescent materials always remains a challenge for enhancing photoluminescence quantum yield (PLQY). Herein, we report two divalent Sr‐based hybrid iodides, (Ph 3 MeP)SrI 3 and (Ph 3 EtP)SrI 3 (Ph 3 MeP = methyltriphenylphosphonium, Ph 3 EtP = ethyltriphenylphosphonium), and equivalent Eu/Sr alloying have been identified experimentally in the full range of 0 ≤ x ≤ 1 for (Ph 3 MeP)Sr (1‐ x ) Eu x I 3 and (Ph 3 EtP)Sr (1‐ x ) Eu x I 3 . These Eu/Sr‐based hybrid iodides exhibit 1D [Sr (1‐ x ) Eu x I 6 ] 4− octahedra chains, suppressing nonradiative energy loss effectively by maintaining optimal spacing and dispersion between adjacent Eu(II) emission centers. Upon even heavily Eu(II) alloying, (Ph 3 MeP)Sr 0.5 Eu 0.5 I 3 exhibits efficient green emission ( λ em = 525 nm) with a high PLQY of ∼92.2%. Accordingly, it achieves a high scintillation light yield of 54 000 ± 300 ph MeV −1 and a low detection limit of 49.9 nGy s −1 . Furthermore, ceramic wafers counterparts of Eu/Sr alloy prepared via cold sintering process demonstrate high‐resolution X‐ray imaging with a spatial resolution up to 15.7 lp mm −1 . These findings not only present a new family of hybrid bimetallic iodides via Eu/Sr alloying, but also provides structurally guided strategy to suppress concentration quenching toward bright luminescence for scintillation applications.
Article Details
Authors (7)
Lihan Chen
College of Computer and Data Science
Shuai Zhang
Yuzhen Wang
State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, School of Physics and Optoelectronics
Liang Li
Dongdan Chen
State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques School of Materials Science and Engineering South China University of Technology Guangzhou 510641 China
Kai Han
Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering, Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Center for Quantum Technology Research and School of Physics
Zhiguo Xia
State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, School of Physics and Optoelectronics