Pan Zai-Fa, Liu Shuang, Zhu Cheng-Jing, Xu Juan, Liu Wen-Han, Wang Li-Li
College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2011 Nov;31(11):2910-3.
A single-host white-light-emitting phosphor BaSrMg(PO4)2 : EU2+ was prepared by high temperature solid-state reaction method, and the luminescence characteristics and XRD pattern were investigated. The results showthat BaSrMg(PO4)2 phase was obtained by sintering at 1 200 degrees C for 3 hours. BaSrMg(PO4)2 = Eu2+ phosphor exhibits two main emission bands peaking at 424 and 585 nm, respectively. The emission band peaking at 424 nm is attributed to the 4f 6 5d1 --> 4f7 transition of Eu2+ substituting Sr2+, while the emission band peaking at 585 nm originates from the 4f 6 5d1 --> 4f7 transition of Eu2+ replacing Ba2+ in host lattice. The excitation spectra of the two emission peaks are range from 250 to 400 nm and both peaking at 360 nm. The effect of the proportion of Ba and Sr, and the Eu2+ doping concentration on the emission intensity were discussed in detail. Different chromaticity coordinates were obtained for each phosphor, that is, the chromaticity coordinates of the designed phosphor is tunable for the white-emitting LED or for special purpose. Quantum efficiency was also examined for the phosphors with different Eu2+ doping concentration, and concentration quenching took place obviously when Eu2+ doping concentration was lager than 6% in mole ratio. The obtained phosphor BaSrMg(PO4)2 : Eu2+ can be excited by near ultraviolet radiation effectively and emit full color lighting, which is a promising single-host white-light-emitting phosphor for white LED.
采用高温固相反应法制备了单基质白光发射荧光粉BaSrMg(PO4)2:Eu2+，并对其发光特性和XRD图谱进行了研究。结果表明，在1200℃烧结3小时可得到BaSrMg(PO4)2相。BaSrMg(PO4)2:Eu2+荧光粉呈现出两个主要发射带，分别在424和585nm处达到峰值。在424nm处达到峰值的发射带归因于Eu2+取代Sr2+时的4f65d1→4f7跃迁，而在585nm处达到峰值的发射带则源于Eu2+在基质晶格中取代Ba2+时的4f65d1→4f7跃迁。两个发射峰的激发光谱范围为250至400nm，且均在360nm处达到峰值。详细讨论了Ba和Sr的比例以及Eu2+掺杂浓度对发射强度的影响。每种荧光粉都获得了不同的色度坐标，即所设计荧光粉的色度坐标可针对白光发光二极管或特殊用途进行调节。还对不同Eu2+掺杂浓度的荧光粉的量子效率进行了检测，当Eu+掺杂浓度在摩尔比大于6%时，明显发生浓度猝灭。所制备的荧光粉BaSrMg(PO4)2:Eu2+能被近紫外辐射有效激发并发出全色光，是一种有前途的用于白光发光二极管的单基质白光发射荧光粉。
