Eu3+이온이 첨가 된 Na3Gd(PO4)2와 LiGd9(SiO4)6O2의 VUV-UV 분광학 연구

Abstract

VUV-UV Spectroscopy of Eu3+ Ions doped in Na3Gd(PO4)3 and LiGd9(SiO4)6O2

Byeong Cheon Jeon

Department of Physics Pukyong National University

Abstract

Eu3+ - doped and un-doped Na3Gd(PO4)3, LiGd9(SiO4)6O2 phosphors were synthesized by solid-state reaction at high temperature in the air atmosphere. The formation of single phase Na3Gd(PO4)3 and LiGd9(SiO4)6O2 were confirmed by X-ray powder diffraction analysis. The emission and excitation spectra of Na3Gd(PO4)3:Eu3+ were obtained under the (vacuum ultraviolet) VUV excitation. The difference in excitation and emission spectra between Eu3+ doped and un- doped samples are discussed. We observe the strong emission line at 313 nm due to the 6P7/2 ∪ 8S7/2 transition of Gd3+ under the VUV excitation in the region of 170 - 185nm. In the spectra under the both VUV and UV excitations, the strong red emission at around 610 nm due to the 5D0 ∪ 7F2 transition of Eu3+ indicating small amount of unwanted Eu3+ ions are present even in un-doped Na3Gd(PO4)3 and LiGd9(SiO4)6O2 Obtained by monitoring at 313 and 610 nm emissions, we observe different excitation spectra in the VUV ？C UV region indicating that the energy transfer occurs from exciton band of host lattice to Gd3+ and then to Eu3+. The strong charge transfer band of Eu3+ - O2- in Na3Gd(PO4)3 appears in the excitation spectra in the wavelength region 240 ？C 270 nm. In the present, we discuss the difference in luminescence properties by changing the doping concentration of Eu3+ in Na3Gd(PO4)3 and LiGd9(SiO4)6O2