Electronic structure and photoluminescence of Dy3+ single-doped and Dy3+/Tm3+ co-doped NaBi(WO4)2 phosphors
Electronic structure and photoluminescence of Dy3+ single-doped and Dy3+/Tm3+ co-doped NaBi(WO4)2 phosphors
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DOI：
10.1016/j.optmat.2018.12.029
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发表时间：
2019-02-01
影响因子：
3.9
通讯作者：
Wang, Bo
中科院分区：
文献类型：
--
作者：
Huang, Jianhui;You, Weixiong;Wang, Bo
采用高温固相法制备了单相白色发光材料NaBi（WO 4）（2）：Dy 3+，Tm 3+。采用第一性原理计算方法研究了NaBi（WO 4）（2）的电子结构。计算结果表明，NaBi（WO 4）（2）的间接带隙为3.02 eV。用扫描电镜、X射线粉末衍射和光致发光谱分别表征了荧光粉的晶体结构和发光性能。结果表明，所制备的荧光粉均为四方晶系，空间群为Id。PL测试结果表明，所制备的荧光粉可被365 nm有效激发，产生白色光发射。然后研究了基质NaBi（WO 4）（2）中Dy ~（3+）和Tm ~（3+）之间的能量传递。最后，优选的NaBi 0.91-x（WO 4）（2）：0.09 Dy（3+），0.11 Tm 3+的色坐标（0.3319，0.3395）接近标准白色光点（0.333，0.333）。所有这些结果表明，NaBi（WO 4）（2）：Dy 3 +/Tm 3+是一种很有潜力的用于UV基w-LED的单相白色发光材料。
A single-phase white light emitting NaBi(WO4)(2):Dy3+, Tm3+ phosphor has been successfully prepared by conventional high-temperature solid-state method. First-principles calculations were used to investigate the electronic structures of NaBi(WO4)(2). The calculation results show that NaBi(WO4)(2) has an indirect band gap with 3.02 eV. The crystal structure and PL properties of the obtained phosphor are characterized by SEM, powder X-ray and photoluminescence spectra, respectively. The results demonstrate that all as-prepared crystalline in a tetragonal crystal system with a space group of Id. PL results confirmed that the obtained phosphors can be efficiently excited by 365 nm and generated white light emission. Then the energy transfer between Dy3+ and Tm3+ in the host NaBi(WO4)(2) was investigated. Finally, the chromaticity coordinates of preferred NaBi0.91-x(WO4)(2):0.09Dy(3+), 0.11 Tm3+ (0.3319, 0.3395) were close to the standard white light point (0.333, 0.333). All these results reveal that NaBi(WO4)(2):Dy3+/Tm3+ was a potential single phase white light-emitting phosphor candidate for NUV-based w-LEDs.