采用水热法制备了可用于白光LED的红色发光材料BaSrMg(PO4)2∶Eu3+。 通过X射线衍射(XRD)和场发射扫描电子显微镜(FESEM)对其结构和形貌进行测试表征, 研究了不同pH值(5, 6, 7和8)和不同反应温度(120, 140, 160, 180和 200 ℃)对荧光粉的晶体结构和形貌的影响。 从XRD的结果可以看到, 当pH 6时合成的样品的衍射峰为较高强度的锐锋, FESEM扫描图像也显示该制备条件下获得了立方体形状的规则晶体。 在pH值分别为5, 7, 8时所制备的样品XRD图谱中大多是强度很弱的宽峰叠加了极少的锐锋, 表明样品为固熔体或者含有混合相, 这与FESEM扫描图像所显示的无定形态颗粒的结果相一致。 荧光光谱测试结果表明, 该荧光粉在394 nm波长光的激发下产生的发射谱包含了以下6组发射峰536 nm（5D1→7F1）, 578 nm（5D0→7F0）, 590 nm（5D0→7F1）, 613 nm（5D0→7F2）, 646 nm(5D0→7F3)和696 nm(5D0→7F4）。 荧光粉的激发光谱分别由361 nm(7F0→5D4), 380 nm(7F0→5L8),　394 nm(7F0→5L6)和464 nm(7F0→5D2)四组激发峰组成。 经过条件优化后制备的荧光粉的主要激发峰在394 nm(7F0 →5L6), 该荧光粉在394 nm波长光激发下产生的发射峰主峰在613 nm(5D0 →7F2)。 发射峰的劈裂随着pH值和温度的变化而改变, 这一现象说明了荧光粉的发光性质与它的晶体结构和颗粒形貌存在着密切的联系。

Eu3+ doped BaSrMg(PO4)2 were prepared by a hydrothermal method. The crystal structure and morphology of BaSrMg(PO4)2∶Eu3+ phosphor were characterized by X-ray powder diffraction(XRD) and field emission scanning electron microscopy(FESEM). The effects of different pH values (5, 6, 7 and 8) and different reaction temperatures (120, 140, 160, 180　and 200 ℃) on the crystal structure and morphology of BaSrMg(PO4)2∶Eu3+ phosphor were studied in this paper. The results of XRD indicate that diffraction peaks are sharp and strong only when pH value is 6, meanwhile the FESEM shows the morphology is regular-shaped. The XRD patterns show amorphous halos superimposed with several weak sharp peaks for the samples preparing under the pH values of 5, 7 and 8. It indicates that these three samples are solid solution or mixed phases, which are in accord with the results of FESEM. From the fluorescence spectra, the peaks in the excitation spectra were assigned to the transition from 7F0 to 5D4, 5L8, 5L6 and 5D2, while the peaks of emission spectra corresponding to the transition of 5D1→7F1 and 5D0→7FJ (J= 0, 1, 2, 3 and 4). The strongest emission peak of the optimized phosphor located at 613 nm (5D0→7F2), excited by the main excitation peak with wavelength of 394 nm. The splitting of the emission peaks changes depends on pH values and temperatures, which indicating that luminescence properties is closely related to the crystal structure and morphology of particles.