水热法制备Sr_(2)LuF_(7):Ln^(3+)(Ln=Yb,Er,Ho)荧光粉及其温敏性能探究

Hydrothermal Preparation and Temperature-Sensitive Properties of Sr_(2)LuF_(7):Ln 3+(Ln=Yb,Er,Ho)Phosphors

利用无模板水热法成功合成出Sr_(2)LuF_(7):Ln^(3+)/Ho^(3+)/Er^(3+)等一系列荧光粉,不断调节掺杂离子的浓度,得到基于Sr_(2)LuF_(7)基质中的最佳掺杂浓度比为20%Yb^(3+),3%Ho^(3+),并出现了浓度猝灭现象,由此可判断Yb^(3+)/Ho^(3+)之间存在能量传递。通过改变泵浦功率的大小,发现在980 nm光源激发下Sr_(2)LuF_(7):Ln^(3+)/Ho^(3+)荧光粉的发光过程为双光子过程,并分析了Yb^(3+)/Ho^(3+)之间可能的能量传递过程。最后研究了在323~523 K温度区间内,Sr_(2)LuF_(7):20%Yb^(3+),3%Er^(3+)荧光粉的温度传感性能,基于2H 11/2和4S 3/2这两个热耦合能级计算出荧光强度比(FIR),FIR对温度的依赖性,随着温度的升高,FIR不断减小。随后利用荧光强度比与温度的依赖关系计算了材料的相对灵敏度,得出在323 K时达到最大灵敏度,为1.016%K-1,可以认为Sr_(2)LuF_(7):20%Yb^(3+),3%Er^(3+)是一种有前途的温度传感材料。

A series of phosphors such as Sr_(2)LuF_(7):Ln^(3+)/Ho^(3+)/Er^(3+)were synthesized by templateless hydrothermal method,by continuously adjusting the concentration of doped ions,and the optimal doping concentration ratio in Sr_(2)LuF_(7)matrix is 20%Yb^(3+)and 3%Ho^(3+),and the concentration quenching phenomenon occurs,thus it can be judged that there is energy transfer between Yb^(3+)/Ho^(3+).By changing the pump power,it is found that the luminescence process of Sr_(2)LuF_(7):Ln^(3+)/Ho^(3+)phosphor is a two-photon process under the excitation of 980 nm light source,and the possible energy transfer process between Yb^(3+)/Ho^(3+)was analyzed.Finally,the temperature sensing performance of Sr_(2)LuF_(7):20%Yb^(3+),3%Er^(3+)phosphors was studied in the temperature range of 323~523 K,based on the two thermal coupling energylevels of 2H 11/2 and 4S 3/2,the FIR was calculated and the dependence of FIR on temperature was analyzed.The dependence of FIR on temperature was analyzed,FIR decreased continuously with the increase of temperature,.Then,the relative sensitivity of the material was calculated by using the dependence of fluorescence intensity ratio and temperature,and the maximum sensitivity was obtained at 323 K,which was 1.016%K-1.It can be considered that Sr_(2)LuF_(7):20%Yb^(3+),3%Er^(3+)are promising temperature sensing materials.