Zn,Cd对CaTiO3：Pr3+的发光性质的影响

采用高温固相反应合成CaTiO₃:Pr³⁺、Zn₂TiO₄、Ca_0.7Zn_0.3-xCd_xTiO₃:Pr³⁺(x=0.01,0.03,0.05,0.07,0.09,0.1)红色系列粉末状发光材料。经X射线衍射检测其结构,CaTiO₃结构为正交晶系,其结果与JCPDS标准卡(42-423)相符。Zn₂TiO₄结构属立方晶系,结果与JCPDS标准卡(25-1164)一致。Ca_0.7Zn_0.3-xCd_xTiO₃:Pr³⁺(x=0.01,0.03,0.05,0.07,0.09,0.1)由两种物相组成,一种为CaTiO₃,另一种为Zn₂TiO₄。检测了材料的激发光谱和发射光谱。发现,在CaTiO₃:Pr³⁺中加入适量Zn可形成Zn₂TiO₄相,使材料的激发光谱在324nm附近的吸收增强。少量Cd可进入Zn₂TiO₄晶格,增强激发光谱在324nm附近的吸收,同时提高发射光谱的强度;但过量的Cd的加入会导致发射光谱强度下降。

Effect of Zn,Cd on the Luminescent Properties of CaTiO3∶Pr3+

The samples of CaTiO₃:Pr³⁺,Zn₂TiO₄:Pr³⁺,Ca_0.7Zn_0.3-xCd_xTiO₃:Pr³⁺(x=0.01,0.03,0.05,0.07,0.09,0.1)were synthesized by the conventional solid state reaction.XRD measurements confirmed that the prepared CaTiO₃:Pr³⁺ and the Zn₂TiO₄:Pr³⁺ belonged to orthorhombic structure according with JCPDS Card(42-423)and cubic structure according with JCPDS Card(25-1164),respectively.The XRD profile of the Ca_0.7Zn_0.3-xCd_xTiO₃:Pr³⁺(x=0.01,0.03,0.05,0.07,0.09,0.1)showed the two phases which were CaTiO₃:Pr³⁺ and Zn₂TiO₄:Pr³⁺ respectively.The excitation spectra of CaTiO₃:Pr³⁺ were located at 150~350 nm,and composed of two continuous zone:the first one originated about 230 nm,the second one originated around 321 nm.Both hailed from the absorption of the transition O(2p)→Ti(3d).The excitation spectra of Zn₂TiO₄:Pr³⁺ around 324 nm differed from that of CaTiO₃:Pr³⁺,and the excitation spectra of Ca_0.7Zn_0.3TiO₃:Pr³⁺ showed the characteristics of both the CaTiO₃:Pr³⁺ and the Zn₂TiO₄:Pr³⁺,which indicated the effect of substitution or partial substitution of Zn for Ca on the luminescent properties of CaTiO₃:Pr³⁺.In contrast with the Ca_0.7Zn_0.3TiO₃:Pr³⁺,the excitation spectra of Ca_0.7Zn_0.3-xCd_xTiO₃:Pr³⁺(x=0.01,0.03,0.05,0.07,0.09,0.1)were intensified at the narrow peak about 324 nm,which indicated the effect of partial substitution Cd for Zn on the luminescent properties of Ca_0.7Zn_0.3TiO₃:Pr³⁺.The all emission spectra have a sharp peak of Pr³⁺ at about 612 nm characterizing the transition of ¹D₂→³H₄ of Pr³⁺.The intensity of emission peaks of Ca_0.7Zn_0.3-xCd_xTiO₃:Pr³⁺(x=0.01,0.03,0.05,0.07,0.09,0.1)was increased with increasing of x value when the x was in the range of 0.01～0.07.