Novel Na3Sc2(PO4)3:Ce3+,Tb3+ phosphors for white LEDs: Tunable blue-green color emission, high quantum efficiency and excellent thermal stability
Novel Na3Sc2(PO4)3:Ce3+,Tb3+ phosphors for white LEDs: Tunable blue-green color emission, high quantum efficiency and excellent thermal stability
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DOI：
10.1016/j.dyepig.2017.12.051
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发表时间：
2018-04-01
影响因子：
4.5
通讯作者：
Huang, Xiaoyong
中科院分区：
文献类型：
--
作者：
Guo, Heng;Devakumar, Balaji;Huang, Xiaoyong
本文采用传统的固相法合成了Ce3+和Tb3+单掺以及Ce3+/Tb3+共掺的Na3Sc2(PO4)(3)荧光粉，并对其晶体结构、形貌、发光性能、随温度变化的发射光谱和量子效率进行了详细的研究。Ce3+单掺杂样品在320 nm激发下表现出强烈的蓝光发射。Na3Sc2(PO4)(3)：Tb3+荧光粉在450-650 nm范围内有四个发射带，最大发射波长在542 nm左右。此外，Ce3+和Tb3+共掺的Na3Sc2(PO4)(3)荧光粉中Ce3+到Tb3+离子之间发生了有效的能量转移，能量转移机制是电偶极-偶极相互作用的结果。通过调节Na3Sc2(PO4)(3)：Ce3+，Tb3+荧光粉中Tb3+的掺杂浓度，其发光颜色可以从深蓝(0.171，0.050)调到绿色(0.299，0.593)，当Tb3+的摩尔分数为10mol%时，绿色发光强度达到最大。Na3Sc2(PO4)(3)：0.03Ce(3+)，0.1Tb(3+)样品具有较高的内量子效率(65%)和良好的热稳定性(激活能为0.245 eV)。在423K下，Na3Sc2(PO4)(3)：0.03Ce(3+)，0.1Tb(3+)的相对发射强度约为303K时的85.6%，这表明Na3Sc2(PO4)(3)：Ce3+，Tb3+化合物有可能成为荧光粉转换白色发光二极管的变色器。
In this paper, Ce3+ and Tb3+ singly doped as well as Ce3+/Tb3+ co-doped Na3Sc2(PO4)(3) phosphors were synthesized by the traditional solid-state method and their crystal structure, morphology, luminescence properties, temperature-dependent emission spectra and quantum efficiency were investigated in detail. The Ce3+ singly doped sample exhibited intense blue emission under 320 nm excitation. The Na3Sc2(PO4)(3):Tb3+ phosphors showed four emission bands in the wavelength range of 450-650 nm with a maximum at about 542 run. Furthermore, efficient energy transfer from Ce3+ to Tb3+ ions occurred in Ce3+ and Tb3+ co-doped Na3Sc2(PO4)(3) phosphors, and the electric dipole-dipole interactions was responsible for the energy transfer mechanism. By adjusting Tb3+ doping concentration in Na3Sc2(PO4)(3):Ce3+,Tb3+ phosphors, their emission colours can be tuned appropriately from deep blue (0.171, 0.050) to green (0.299, 0.593), and the intensity of green emission reached the maximum at 10 mol% Tb3+. The Na3Sc2(PO4)(3):0.03Ce(3+),0.1Tb(3+) sample possessed high internal quantum efficiency of 65% and also excellent thermal stability with an activation energy of 0,245 eV. The relative emission intensity of Na3Sc2(PO4)(3):0.03Ce(3+),0.1Tb(3+) at 423 K was found to be about 85.6% of its initial value at 303 K. These results indicate the potential of Na3Sc2(PO4)(3):Ce3+,Tb3+ compounds as candidates for color converters in phosphor-converted white light-emitting diodes.