The luminescent properties of a ZnGa₂O₄spinel doped with Eu³⁺and Er³⁺ions

Abstract

Nanophosphor of ZnGa2O4:Eu3+ and Er3+ were synthesized by the hydrothermal method. ZnGa2O4 is an intrinsic blue light emitter with a wavelength peak of approximately 608 nm depending on the gallium ratio. A luminescent analysis of the materials shows that the rare earth ions are localized in the defect sites at the crystallite boundaries. The emission spectra of the europium-doped samples are characterized by an intense emission in the red region due to the 5D0–7F1, 2 transitions of Eu3+ ions, whereas in the case of erbium doping the highest intensity corresponds to the green light emission due to the 4I13/2–4I15/2 transitions of the Er3+ ions. These powders were analyzed by x-ray diffraction (XDR) and characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDAX) and atomic force microscopy (AFM). Photoluminescence (PL) and photoluminescence excitation (PLE) measurements were made with a conventional lamp as an excitation source.