Co-precipitation synthesis, photoluminescence properties and theoretical calculations of MgWO4:Eu3+ phosphors

Abstract

A novel red light emitting phosphorescent material MgWO₄:Eu³⁺ is successfully synthesized by the co-precipitation method. The structure, luminescent properties and fluorescence lifetime of the prepared phosphors are characterized using X-ray diffraction (XRD), photoluminescence and luminescence decay spectra. The results indicate that an effective electric dipole transition ⁵D₀–⁷F₂ of Eu³⁺ red emission with maxima at 615 nm can be achieved in the MgWO₄ host while being excited by near-UV light (393 nm) or blue light (464 nm). The CIE chromaticity coordinates of MgWO₄:Eu³⁺ phosphors exhibit emission in the red-light region. Moreover, to explain the fluorescence spectra of MgWO₄:Eu³⁺ phosphors, a complete energy matrix is successfully built by an effective operator Hamiltonian including free ion and crystal field interactions. The fluorescence spectra for the Eu³⁺ ion at the monoclinic (C_2v) Mg²⁺ site of the MgWO₄ crystal are calculated from this matrix. The fitting values are in agreement with the observed results.