荧光粉
离子
分析化学(期刊)
材料科学
兴奋剂
发光二极管
发光
发射强度
热稳定性
发射光谱
半最大全宽
光电子学
化学
谱线
物理
色谱法
有机化学
天文
作者
Yuqing Yan,Fei Huang,Guanyu Zhu,Yi Zhang,Zhexuan Gao,Huanping Wang,Degang Deng,Hua Yu,Shiqing Xu
标识
DOI:10.1002/lpor.202401588
摘要
Abstract Broadband near‐infrared (NIR) phosphors activated by Cr 3+ ions are critical for developing NIR phosphor‐converted light‐emitting diodes (pc‐LEDs). The temperature‐dependent behaviors of the narrowband 2 E → 4 A 2 and broadband 4 T 2 → 4 A 2 transitions of Cr 3+ ions differ, which makes Cr 3+ ‐activated phosphors highly promising for ratio optical thermometers. How to obtain Cr 3+ ‐activated phosphors with both high luminescence efficiency and thermal stability is a challenge. Herein, a strategy of adjusting the doping levels is adopted to precisely control the exchange coupling between Cr 3+ ions in LiAl 5 O 8 : Cr 3+ phosphors. As Cr 3+ ions doping concentration increases, the NIR emission shifts from narrowband to broadband. Under heavy doping concentrations, the sample exhibits an unusual broadband emission in a strong crystal field, covering 645 to 1300 nm, with a peak emission wavelength of 950 nm and a FWHM of 295 nm. Simultaneously, a high internal quantum efficiency ( IQE = 85%) and excellent thermal stability ( I 423K / I 293K = 86%) are achieved, highlighting the broad application potential of the developed NIR pc‐LEDs. Interestingly, under low‐concentration doping, the sample exhibits dual emission characteristics, and the temperature dependence of its two emission peaks shows opposite trends. Utilizing fluorescence intensity ratio (FIR) technology, the sample achieves a relative sensitivity of 0.30% K⁻¹, highlighting its promising potential for temperature sensing applications.
科研通智能强力驱动
Strongly Powered by AbleSci AI