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.

中文翻译：

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用于高功率 NIR-LED 光源的 Cr3+ 掺杂荧光粉实现高性能的策略。


宽带近红外 (NIR) 发射荧光粉是基于蓝色 LED 的下一代智能 NIR 光源的关键。为了获得优异的近红外荧光粉，我们提出了提高结晶度、改变微形貌并保持 Ca3Sc2Si3O12 石榴石 (CSSG) 中 Cr3+ 价态的策略。通过添加助熔剂并在还原气氛中烧结，内量子效率（IQE）大大提高至92.3%。优化后的CSSG:6%Cr3+表现出优异的热稳定性。在150℃时，可以保持室温下97.4%的NIR发射。所制造的 NIR-LED 器件在 520 mA 电流下发出 109.9 mW 的高光功率。所获得的荧光粉和NIR-LED的性能几乎是迄今为止最好的结果。研究了优化的机制。演示了 NIR-LED 光源的应用。