Yang Ye, Lu Zuizhi, Fan Hua, Chen Mianhong, Shen Linawa, Zhang Xinguo, Pang Qi, Chen Jianhua, Chen Peican, Zhou Liya
School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China.
Inorg Chem. 2023 Feb 27;62(8):3601-3608. doi: 10.1021/acs.inorgchem.2c04347. Epub 2023 Feb 15.
Near-infrared (NIR) phosphor-converted light-emitting diodes with broadband emission have received considerable interest. However, there remains a challenge in the construction of ultra-broadband NIR phosphors, hindering their further application. In this work, a heterovalent substitution strategy is proposed to construct a novel ultra-broadband NIR-emitting LaTiTaO:Cr phosphor with a full width at half maximum of ∼300 nm. Crystal structure, time-resolved emission spectroscopy, and electron paramagnetic resonance analyses confirm that only one crystallographic site of Cr with separated ions exists. Electron and phonon coupling (EPC) evaluated by the Huang-Rhys factor () reveals that the heterovalent substitution strategy contributes to strong EPC with = 9.185, resulting in ultra-broadband emission. Interestingly, a remarkable blue shift of emission from 1050 to 922 nm with increasing temperature is observed. Moreover, the application of LaTiTaO:Cr phosphor is demonstrated in the qualitative analysis of ethanol/water mixtures. The work will enrich the toolbox for designing broadband NIR-emitting materials.
具有宽带发射的近红外（NIR）磷光体转换发光二极管已引起了广泛关注。然而，在构建超宽带近红外磷光体方面仍然存在挑战，这阻碍了它们的进一步应用。在这项工作中，提出了一种异价取代策略，以构建一种新型的超宽带近红外发射LaTiTaO:Cr磷光体，其半高宽约为300 nm。晶体结构、时间分辨发射光谱和电子顺磁共振分析证实，仅存在具有分离离子的Cr的一个晶体学位置。通过黄昆因子（）评估的电子与声子耦合（EPC）表明，异价取代策略有助于产生强EPC， = 9.185，从而导致超宽带发射。有趣的是，随着温度升高，观察到发射从1050 nm显著蓝移至922 nm。此外，还展示了LaTiTaO:Cr磷光体在乙醇/水混合物定性分析中的应用。这项工作将丰富用于设计宽带近红外发光材料的工具箱。
