A series of (Y,Tb)3Al5O12:Ce3+, Sm3+ phosphors were prepared by a sol-gel combustion method. The crystal structure and photoluminescent property under different Sm3+ concentrations were investigated. The results by Rietveld method of whole pattern fitting indicate that the structure of all the samples is a cubic garnet. With increasing in Sm3+ concentration, the lattice constants increase monotonously. The red light emitting centered at 617 nm is the result of the one-way energy transition from Ce3+ ions to Sm3+ ions. Tb3+ ions substitution would go against the energy transition from Ce3+to Sm3+. The yellow light emitting from Ce3+ ions shifts to a longer wavelength followed the complex effects of the stronger crystal field around Ce3+ ions and its stronger covalence of chemical bond with O2-ions. Within Sm3+ codoped TAG:Ce system, the path for the activation energy transfer from the sensitizer Ce3* ions to the activator Sm3+ ions involves transferring from the 5d→4f2F5/2,7/2 and 7F6-→5D(Tb3+) to 4G5/2→6H7/2(Sm3+).%采用柠檬酸溶胶凝胶燃烧合成法制备了一系列组成的(Y,Tb)3Al5O12:Ce3+,Sm3+荧光粉.通过X射线衍射、荧光光谱研究了不同Sm3+离子共掺杂浓度下(Y,Tb)AG:Ce3+荧光粉的晶体结构及光致发光性能.Rietveld全图拟合(Rietveld method of whole pattern fitting)结果表明:掺杂后样品仍为纯立方石榴石相,随着Sm3+离子共掺杂浓度的增加,样品的晶胞参数增大.在467 nm激发下,激发能由Ce3+离子向Sm3+离子单向传递,从而在617nm处出现红光发射.Tb3+离子取代不利于Ce3+离子与Sm3+离子的能量传递,同时Ce3+离子受更强的晶体场作用及与O2-离子间增强的共价性使发射主峰红移,Sm3+掺杂的TAG:Ce体系中,激发能由敏化剂Ce3+离子向激活剂Sm3+离子的传递路径包括5d→4ffF5/2,7/2(Ce3+)和7F6→5D4(Tb3+)到4G52→6H7/2(Sm3+)两部分.
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