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Strategies to approach high performance in Cr³⁺-doped phosphors for high-power NIR-LED light sources.

ABSTRACT: Broadband near-infrared (NIR)-emitting phosphors are key for next-generation smart NIR light sources based on blue LEDs. To achieve excellent NIR phosphors, we propose a strategy of enhancing the crystallinity, modifying the micromorphology, and maintaining the valence state of Cr³⁺ in Ca₃Sc₂Si₃O₁₂ garnet (CSSG). By adding fluxes and sintering in a reducing atmosphere, the internal quantum efficiency (IQE) is greatly enhanced to 92.3%. The optimized CSSG:6%Cr³⁺ exhibits excellent thermal stability. At 150 °C, 97.4% of the NIR emission at room temperature can be maintained. The fabricated NIR-LED device emits a high optical power of 109.9 mW at 520 mA. The performances of both the achieved phosphor and the NIR-LED are almost the best results until now. The mechanism for the optimization is investigated. An application of the NIR-LED light source is demonstrated.

SUBMITTER: Jia Z

PROVIDER: S-EPMC7229223 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Strategies to approach high performance in Cr3+-doped phosphors for high-power NIR-LED light sources.

Jia Zhenwei Z Yuan Chenxu C Liu Yongfu Y Wang Xiao-Jun XJ Sun Peng P Wang Lei L Jiang Haochuan H Jiang Jun J

Light, science & applications 20200515

Broadband near-infrared (NIR)-emitting phosphors are key for next-generation smart NIR light sources based on blue LEDs. To achieve excellent NIR phosphors, we propose a strategy of enhancing the crystallinity, modifying the micromorphology, and maintaining the valence state of Cr3+ in Ca3Sc2Si3O12 garnet (CSSG). By adding fluxes and sintering in a reducing atmosphere, the internal quantum efficiency (IQE) is greatly enhanced to 92.3%. The o ...[more]

PMID: 32435469

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