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Ag Nanocluster-Enhanced Scintillation Properties of Borophosphate Glasses Doped with CsPbBr₃ Quantum Dots.

ABSTRACT: A novel and effective method to improve scintillation properties of glass-ceramics, such as intensity enhancement and decay-time shortening, is reported in this work. Compared with crystal scintillators, glass scintillators always have the problems of low efficiency and long decay; how to solve them has always been a scientific puzzle in the field of scintillation glass-ceramics. The plasma enhancement effect can be predicted to solve the above problems. Ag⁺ ions were diffused into glasses by ion exchange, and then Ag nanoparticles and CsPbBr₃ quantum dots were formed by heat treatment. The structure of the CsPbBr₃ perovskite consists of a series of shared corner PbBr₆ octahedra with Cs ions occupying the cuboctahedral cavities. By using Ag and the plasma resonance effect, the photoluminescence intensity of CsPbBr₃ quantum dot glasses was enhanced by 3 times, its radioluminescence intensity increased by 6.25 times, and its decay time was reduced by a factor of more than one. Moreover, the mechanism of photoluminescence and radioluminescence enhanced by Ag and plasma was discussed based on the experimental results and finite-difference time-domain method. We concluded that the increase in radioluminescence intensity was related to plasma enhancements and the energy exchange between Ag nanoclusters and CsPbBr₃ quantum dots. Doping Ag is a valid means to improve the scintillation luminescence of CsPbBr₃ quantum dot glasses, which can be applied in the field of scintillation.

SUBMITTER: Du Y

PROVIDER: S-EPMC9330410 | biostudies-literature |

REPOSITORIES: biostudies-literature

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