Ding Xin, Wang Yuhua
Key Laboratory of Special Function Materials and Structure Design, School of Physical Science and Technology, Lanzhou University, Tianshui South Road No. 222, Lanzhou, Gansu 730000, P. R. China.
Phys Chem Chem Phys. 2017 Jan 18;19(3):2449-2458. doi: 10.1039/c6cp08300e.
A novel apatite mineral of Ba(PO)SiO was synthesized successfully using a traditional high temperature solid-state reaction. Its structure was determined by high-resolution transmission electron microscopy, fast Fourier transform, energy dispersive X-ray spectroscopy, and X-ray powder diffraction Rietveld refinement, and this was found to be a hexagonal crystal system with the space group attributed to P63/m (176). Moreover, a series of Eu doped Ba(PO)SiO phosphors were investigated. The photoluminescence (PL) properties of Ba(PO)SiO:Eu were investigated in detail by density functional theory calculations, diffuse reflection spectra, emission-excitation spectra, decay curves, and temperature dependence spectra. It can emit green light peaking at ∼515 nm under 405 nm NUV excitation with quantum efficiency 31.89%. According to structure and photoluminescence (PL) property analysis, Eu can occupy two kinds of Ba site. The concentration quenching mechanism of Eu could be a d-d interaction luminescence center. It has poor temperature stability properties because of too much temperature-dependent electron-phonon interaction at high temperature. Fabricated white-LEDs using a 405 nm GaN NUV chip combined with a blend of RGB phosphors: CaAlSiN:Eu, Ba(PO)SiO:1%Eu and BAM:Eu, driven by 30 mA current can get warm-white light with chromaticity coordinates (0.355, 0.342) and correlated color temperature (CCT) 4561 K. This demonstrates that Ba(PO)SiO:Eu is a potential green phosphor matching NUV LED chips to get white light.
采用传统高温固态反应成功合成了一种新型的Ba(PO)SiO磷灰石矿物。通过高分辨率透射电子显微镜、快速傅里叶变换、能量色散X射线光谱和X射线粉末衍射Rietveld精修确定了其结构，发现这是一种六方晶系，空间群为P63/m(176)。此外，还研究了一系列Eu掺杂的Ba(PO)SiO荧光粉。通过密度泛函理论计算、漫反射光谱、发射-激发光谱、衰减曲线和温度依赖性光谱详细研究了Ba(PO)SiO:Eu的光致发光(PL)特性。在405 nm近紫外光激发下，它能发射出峰值约为515 nm的绿光，量子效率为31.89%。根据结构和光致发光(PL)特性分析，Eu可以占据两种Ba位。Eu的浓度猝灭机制可能是d-d相互作用发光中心。由于在高温下存在过多的温度依赖性电子-声子相互作用，其温度稳定性较差。使用405 nm GaN近紫外芯片与RGB荧光粉混合物（CaAlSiN:Eu、Ba(PO)SiO:1%Eu和BAM:Eu）制成的白光发光二极管，在30 mA电流驱动下可获得色坐标为(0.355, 0.342)、相关色温(CCT)为4561 K的暖白光。这表明Ba(PO)SiO:Eu是一种与近紫外发光二极管芯片匹配以获得白光的潜在绿色荧光粉。
