Ye Tong, Yu Huijuan, Su Shuai, Liang Huiling, Chen Yan, Zhang Qiuhong, Zhou Jianbang
School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China.
Guangdong Province Key Laboratory of Rare Earth Development and Application, Institute of Resources Utilization and Rare Earth Development, Guangdong Academy of Sciences, Guangzhou 510651, P. R. China.
Inorg Chem. 2025 Sep 8;64(35):18017-18026. doi: 10.1021/acs.inorgchem.5c03361. Epub 2025 Aug 22.
The development of near-infrared (NIR) phosphors with augmented luminous efficiency and robust thermal stability holds pivotal importance for high-performance NIR lighting sources. Herein, LnCaGaGeO:Cr (Ln = Lu, Y, and Gd) compounds are successfully synthesized, and the one with Ln = Lu shows the most intense emission. Subsequently, the luminescence properties of LuCaGaGeO:Cr, which are contingent upon the Cr concentration, are meticulously examined. It is found that replacing Ga with Al can remarkably boost the emission intensity of LuCaGaGeO:Cr. Specifically, the emission intensity of LuCaAlGeO:Cr is 3.69-fold that of LuCaGaGeO:Cr. Nevertheless, despite the high emission intensity of LuCaAlGeO:Cr, its thermal stability is rather poor ( = 21.18%). To address this thermal stability issue, a series of LuCaAlGeO:Cr solid solutions are ingeniously designed through the cosubstitution of Ca-Ge by Lu-Al. This innovative design effectively optimizes the electron population and endows the material with thermal quenching characteristics. Significantly, the sample with = 0.3 maintains nearly 100% of its emission intensity at 423 K when compared with that at room temperature, manifesting a rare zero-thermal quenching performance. Finally, NIR LEDs fabricated by using these optimized phosphors display substantial potential for applications in fields such as nondestructive detection and night vision.
开发具有更高发光效率和强大热稳定性的近红外（NIR）磷光体对于高性能近红外光源至关重要。在此，成功合成了LnCaGaGeO:Cr（Ln = Lu、Y和Gd）化合物，其中Ln = Lu的化合物发射最强。随后，详细研究了LuCaGaGeO:Cr的发光特性，其取决于Cr浓度。发现用Al替代Ga可显著提高LuCaGaGeO:Cr的发射强度。具体而言，LuCaAlGeO:Cr的发射强度是LuCaGaGeO:Cr的3.69倍。然而，尽管LuCaAlGeO:Cr发射强度高，但其热稳定性相当差（= 21.18%）。为了解决热稳定性问题，通过用Lu-Al共取代Ca-Ge巧妙设计了一系列LuCaAlGeO:Cr固溶体。这种创新设计有效优化了电子分布并赋予材料热猝灭特性。值得注意的是，= 0.3的样品在423 K时与室温相比保持近100%的发射强度，表现出罕见的零热猝灭性能。最后，使用这些优化磷光体制备的近红外发光二极管在无损检测和夜视等领域显示出巨大的应用潜力。
