Tb3+ 이온이 도핑된 LiGd9(SiO4)6O2 형광체의 합성과 분광학 연구

Abstract

Tb3+-doped and undoped LiGd9(SiO4)6O2 phosphors were synthesized by solid-state reaction at high temperature in the air atmosphere. The formation of single phase LiGd9(SiO4)6O2 was confirmed by X-ray powder diffraction analysis. The emission and excitation spectra of LiGd9(SiO4)6O2:Tb3+ were obtained under the UV excitation. The difference in excitation and emission spectra between Tb3+-doped and undoped samples are discussed in relation with energy transfer between Gd3+ and Tb3+ and cross relaxation between Tb3+ ions. We observe the strong emission lines at 380 and 545 nm are attributed to the 5D3 → 7F6 transition and the 5D4 → 7F6 transition of Tb3+ in LiGd9(SiO4)6O2. We observe different excitation spectra in the UV region with increasing Tb3+-concentration. The excitation lines of Gd3+ are stronger than those of Tb3+ at low Tb3+-concentration in LiGd9(SiO4)6O2. The changes in relative emission intensity between the 5D3 → 7FJ transition and the 5D4 → 7FJ transition are ascribed to the cross relaxation between Tb3+ ions, especially at high Tb3+-concentration in LiGd9(SiO4)6O2.