Title Tb 3+ and Ce 3+ as a functional couple for enhanced luminescence in YAG ceramics for X-ray imaging and high-power white LEDs and laser diodes
Authors Markovskyi, Anton ; Chewpraditkul, Warut ; Gołębiewski, Przemysław ; Socha, Paweł ; Węglarz, Helena ; Szysiak, Agnieszka ; Jary, Vitezslav ; Kučerková, R ; Tomala, Robert Andrzej ; Yoshikawa, Akira ; Kurosawa, Shunshuke ; Buczyński, Ryszard ; Chewpraditkul, Weerapong ; Bartosiewicz, Karol
DOI 10.1039/D5MA00464K
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Is Part of Materials advances.. Cambridge : Royal Society of Chemistry (RSC). 2025, vol. 6, iss. 22, p. 8464-8478.. eISSN 2633-5409
Abstract [eng] The exposure of luminescent materials to X-ray radiation and high-power laser excitation results in significant heating, leading to thermal quenching and a corresponding reduction in phosphor efficiency. This study aimed to address this limitation by enhancing material efficiency while maintaining high thermal stability. YAG:Ce,Tb transparent ceramics were successfully fabricated via vacuum reactive sintering method, with moderate concentrations of Tb 3+ ions (1, 5 and 10 at%) codopants. These ceramics exhibited a dense microstructure without micropores, achieving high transparency of 77–80% at 900 nm. The incorporation of Tb 3+ ions, is evidenced by the systematic increase in lattice constants from 12.608 Å (YAG:Ce) to 12.615 Å (YAG:Ce,Tb10%) in accordance with Vegard's law. The phonon-assisted Ce 3+ ↔ Tb 3+ bidirectional resonance mechanism, which facilitated energy transfer between Ce 3+ and Tb 3+ ions, was observed. The optimal transfer rate was observed at approximately 480 K. Beyond this temperature, the rate progressively accelerated, leading to accelerated decay times. Notably, YAG:Ce,Tb10% ceramics demonstrated a two-fold increase in radioluminescence intensity compared to uncodoped YAG:Ce ceramics. This substantial improvement in luminescence performance highlights the potential of YAG:Ce,Tb ceramics as highly efficient phosphors for X-ray imaging applications, offering enhanced brightness and energy transfer efficiency under high-temperature operating conditions. The Tb 3+ codoping also enhanced Ce 3+ emission, allowing for tuning of the correlated color temperature to a maximum of 6013 K, while maintaining a stable color rendering index of 69–73 and luminous efficacy of ∼123 lm W −1 . It was shown that the luminous efficacy was not a constant parameter, but depended on the excitation laser power, initially increasing with power up to 0.5 W and then saturating. These results establish YAG:Ce,Tb transparent ceramics as highly promising materials for white LEDs due to their good thermal stability, tunable optical properties, and enhanced luminescence performance.
Published Cambridge : Royal Society of Chemistry (RSC)
Type Journal article
Language English
Publication date 2025
CC license CC license description