Judd-Ofelt analysis and luminescent characterization of Eu3+ activated Li2Zr(PO4)2 phosphor

Abstract

The europium ion (Eu3+) activated lithium zirconium phosphate (Li2Zr(PO4)2) phosphor samples have been synthesized by conventional solid state reaction (SSR) method at high temperature. The obtained phosphor samples crystallize in the hexagonal phase with space group R3C. Photoluminescence (PL) excitation and emission spectra have been recorded and optimum concentration was found to be 2 mol%. In the PL spectra of the synthesized phosphors, a characteristic emission peak observed at 594 nm which is ascribed to the magnetic dipole (MD) dominant transition 5D0→7F1. The colorimetric parameters CCT and CIE Ra values are estimated by CIE chromaticity co-ordinates. Judd-Ofelt (J-O) intensity parameters obtained from emission spectra have been used to evaluate the local site symmetry around Eu3+ ions. The J-O parameters have also been used to calculate the radiative transition probability, branching ratio and radiative lifetime. The gain bandwidth, optical gain parameter and stimulated emission cross-section are also investigated. Thermoluminescence (TL) properties of prepared phosphor have been explained in terms of glow curve and kinetic parameters. The synthesized phosphors are expected to be promising candidates for applications as solid state lighting and optical displays.