MAl_2B_2O_7:Re(M=Ca，Sr，Ba；Re=Eu^(3+)，Tb^(3+))在VUV激发下的发光性能

VUV Luminescence Property of MAl_2B_2O_7;Re(M=Sr,Ba,Ca;Re=Eu^(3+),Tb^(3+))

采用高温固相法合成了MAl_2B_2O_7:Re(M=St,Ba,Ca;Re=Eu^(3+),Tb^(3+))系列样品。BaAl_2B_2O_7:Eu^(3+)在130～170 nm和200～250nm区域有两个很强的吸收带;130～170nm的宽带是硼氧和铝氧基团的吸收,位于200～250nm附近的吸收带主要是Eu^(3+)-O^(2-)电荷转移态的吸收;MAl_2B_2O_7:Eu^(3+)(M=Sr,Ba)中Eu^(3+)占据更多的是非对称格位,以~5D_0→~7F_2跃迁为主,对应613nm处的发射强度最大。MAl_2B_2O_7:Re(M=Sr,Ba;Re=Tb^(3+))在120～200nm和200～300nm光谱区有两个较强的吸收带。位于120～200nm的宽谱带对应于基质吸收。这包括硼氧和铝氧基团在真空紫外的吸收,基质吸收主要是硼酸根的吸收;而位于160～270nm左右的一组谱峰对应于Tb^(3+)的4f^8-4f^75d跃迁;在172nm的激发下,发射峰由492 nm,546nm,592nm和624nm组成,分别对应Tb^(3+)的~5D_4→~7F_J(J=6,5,4,3)跃迁发射,其中546nm是主发峰。

A series of phosphor samples of MAl2B2O7：Re（M= Sr, Ba, Ca; Re=Eu^3＋, Tb^3＋） were prepared by the conventional solid state reaction method. VUV excitation properties and Luminescence properties under VUV excitation were studied. The excitation spectra of MAl2B2O7：Re （M=Sr, Ba, Ca; Re= Eu^3＋） consist of two broad bands： one in the range is from 130 to 170 nm and the other is from 200 to 250 nm. The emission spectral of MAl2B2O7：Re（M= Sr, Ba; Re= Eu^3＋） have revealed that the strong emission line at 613 nm is due to the hypersensitive electric dipole transition of 5D0→^7F2. Hence, the red emission color purity is improved. It was expected that MAl2B2O7：Re（M= Sr, Ba; Re= Eu^3＋） phosphor would be a promising candidate for PDP application. As for MAl2B2O7：Tb^3＋ （M= Sr, Ba, Ca） the VUV excited spectra consists of one broad band in the range from 120 nm to 200 nm and the band peaking around 226 nm, and 270 nm respectively. The band （120-200nm） is also assigned to absorption of the borate groups. The bands which cover the spectral range from 160 to 270nm are due to the transitions of Tb3＋（4f^8→4f^75d ）. The emissions from Tb^3＋ doped MAl2B2O7：Re （M=Sr, Ba, Ca） are mainly attributed to the transitions of ^5D4 to ^7Fj （J=6, 5, 4, 3）.