Crystallographic sites of Eu2+ and Eu2+–Tb3+ energy transfer in Sr2LiSiO4F

Abstract

Eu²⁺ single doped phosphors Sr₂LiSiO₄F:xEu²⁺ and Eu²⁺–Tb³⁺ co-doped phosphors Sr₂LiSiO₄F:0.06Eu²⁺,xTb³⁺ were prepared by a conventional high temperature solid state reaction technique. The photoluminescence spectra of Sr₂LiSiO₄F:xEu²⁺ show that Eu²⁺ ions enter both Sr1 and Sr2 sites in the Sr₂LiSiO₄F host. The PL emission bands of Sr₂LiSiO₄F:xEu²⁺ show a red-shift tendency gradually from 475 to 520 nm with increasing Eu²⁺ content. The photoluminescence spectra as well as the luminescence decays of the co-doped phosphors Sr₂LiSiO₄F:0.06Eu²⁺,xTb³⁺ show that non-radiative energy transfer from Eu²⁺ to Tb³⁺ occurs.