1. Effects of chemical composition control of colquiriite-type neutron scintillator single crystals.
- Author
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Yokota, Yuui, Horiai, Takahiko, and Yoshikawa, Akira
- Subjects
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SINGLE crystals , *SCINTILLATORS , *NEUTRON irradiation , *THERMAL neutrons , *NEUTRONS , *CHEMICAL reactions - Abstract
In this study, charge compensation was performed by co-doping Na + ions at the Ca2+ sites of Ce-doped LiCaAlF 6 single crystals to prevent the generation of cation vacancies owing to Ce3+-doping at the Ca2+ sites. Consequently, an improved radiation resistance and increased light yield under neutron irradiation was achieved. In contrast, the Al metal of the starting material used as a substitute for AlF 3 significantly increased the effective segregation coefficient k eff of the Eu2+ ions in Eu-doped LiCaAlF 6 and Eu-doped LiSrAlF 6 single crystals. The Al metal and EuF 3 in the starting materials produced EuF 2 via a chemical reaction, and the Eu2+ ions in EuF 2 could be substituted at the Ca2+ and Sr2+ sites. In addition, the Ca/Sr ratio control of the Li(Ca,Sr)AlF 6 :Eu solid-solution scintillator single crystals improved the light yield through band-gap control, and the Li(Ca,Sr)AlF 6 :Eu single crystal with a 25% Sr concentration exhibited the highest light yield. Charge compensation was conducted using Na co-doping to improve the radiation resistance of the LiCAF:Ce single crystals, thereby preventing the generation of cation defects by the Ce3+-doping at the Ca2+ site. It was determined that the improvement in the radiation resistance of the LiCAF:Ce single crystal via Na co-doping can contribute to the improvement in the durability of the production of LiCAF:Ce single crystals. [Display omitted] • Scintillation properties of LiCaAlF 6 and LiSrAlF 6 single crystals were improved by chemical composition control. • Charge compensation by Na co-doping for LiCAF:Ce single crystals prevents generations of cation vacancies by Ce3+-doping. • Al metal greatly increases the segregation coefficient of Eu ion in the LiCAF and LiSAF single crystals. • Effective segregation coefficient of Eu2%,AlM1%:LiSrAlF 6 crystal was improved to 0.986 using the Al metal. • Ca/Sr ratio control in the Eu:Li(Ca,Sr)AlF 6 single crystals improves the light yield under thermal neutron irradiation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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