A New Blue-Emitting Oxohalide Phosphor Sr4OCl6:Eu2+ for Thermally Stable, Efficient White-Light-Emitting Devices under Near-UV
A New Blue-Emitting Oxohalide Phosphor Sr4OCl6:Eu2+ for Thermally Stable, Efficient White-Light-Emitting Devices under Near-UV
复制标题
DOI：
10.1021/jp408901c
复制
发表时间：
2014-02-06
影响因子：
3.7
通讯作者：
Im, Won Bin
中科院分区：
文献类型：
--
作者：
Gwak, Sun Joong;Arunkumar, P.;Im, Won Bin
采用固相反应法制备了Sr4OCl6：Eu2+（SOC：Eu2+）蓝色荧光粉。通过Rietveld分析，使用X射线粉末衍射分析包括相纯度的结构性质。为了成功应用于白色发光器件（WLED）产业，研究了SOC：Eu 2+荧光粉的光致发光（PL）特性。在λ（ex）= 370 nm时，SOC：Eu 2+荧光粉具有250~425 nm的宽激发光谱和中心位于446 nm的强蓝色发射带。Eu~（2+）在Sr_（4-x）Eu_xOCl_6中的最佳掺杂浓度为x = 0.02（0.5mol%）。研究了该荧光粉的温度依赖性，结果表明该荧光粉具有很强的抗热猝灭性，在200 ℃时保持了接近91%的亮度。WLED器件是通过将发蓝光的Sr3.98Eu0.02OCl6与商业发红光和绿光的磷光体集成而制造的，用近紫外LED芯片（λ（ex）= 395 nm）激发，并且显示出优异的CIE色坐标（x = 0.32，y = 0.33）。由于基质的结构稳定性、良好的热稳定性和优异的CIE坐标，表明SOC：Eu 2+是一种很有应用前景的白色LED蓝光器件。
New blue-emitting Sr4OCl6:Eu2+ (SOC:Eu2+) phosphor was prepared by solid-state reaction. Structural properties including phase purity were analyzed through Rietveld analysis, using X-ray powder diffraction. The photoluminescence (PL) property of the SOC:Eu2+ phosphor was explored, for its successful application in the white light-emitting devices (WLED) industry. The SOC:Eu2+ phosphor exhibits broad excitation spectra ranging from 250 to 425 nm, and an intense broad blue emission band centered at 446 nm under lambda(ex) = 370 nm. The optimum concentration of Eu2+ in Sr4-xEuxOCl6 was found with x = 0.02 (0.5 mol %). The temperature-dependent PL studies have been investigated, and the phosphor exhibits strong thermal quenching resistance, retaining the luminance of similar to 91% at 200 degrees C. The WLED device was fabricated by integrating the blue-emitting Sr3.98Eu0.02OCl6 with commercial red- and green-emitting phosphor, excited with near UV LED chip (lambda(ex) = 395 nm), and shows excellent CIE chromaticity coordinates (x = 0.32, y = 0.33). The structural stability of the host, good thermal stability, and excellent CIE coordinates suggest that SOC:Eu2+ is a promising blue component for application in the white LED industry.