| Autor: |
Yu, Ting, Sheng, Haoyang, Chen, Shenghai, Yuan, Jian, Deng, Tingting, Wu, Ming, Guo, Yue, Zeng, Qingguang |
| Předmět: |
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| Zdroj: |
Journal of the American Ceramic Society; May2022, Vol. 105 Issue 5, p3403-3417, 15p, 8 Graphs |
| Abstrakt: |
Broadband near‐infrared (NIR) phosphors converted light‐emitting diodes (pc‐LEDs) have attracted tremendous attention for their great potential in NIR spectroscopy applications. Herein, we report on the photoluminescence (PL) properties of Cr3+‐doped Sc(PO3)3, which exhibits a broadband NIR emission centered at 900 nm with a full width at half‐maximum (FWHM) of 161 nm upon excitation at 480 nm. In terms of the examination of spectroscopic parameters, we find that Cr3+ ions occupy a weak crystal field site (Dq/B = 1.94) in the Sc(PO3)3 host with a stronger electron–phonon coupling (Huang‐Rhys factor, S = 5.5), which results in a serious thermal quenching and a low internal quantum efficiency (IQE). Thermal stability and IQE of phosphors can be substantially enhanced by the introduction of Yb3+ ions. In the light of the analysis of excited‐state dynamics, we demonstrate that the enhancement mechanism is ascribed to the efficient Cr3+→Yb3+ energy transfer from the thermal sensitive Cr3+ centers to the thermal stable Yb3+ emitters. An NIR pc‐LED device has been finally fabricated by the combination of a blue‐emitting chip and a Cr3+/Yb3+ codoped Sc(PO3)3 phosphor whose potential application for broadband NIR pc‐LEDs is also discussed. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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