Synthesis and luminescent properties of Eu³⁺-doped ZnO phosphors

Abstract

Eu³⁺-doped ZnO phosphors were prepared with different concentrations of Eu³⁺ ions by using a solid-state reaction method. The synthesized samples were systematically characterized by using X-ray diffraction (XRD), scanning electron microscopy, and photoluminescence spectroscopy. The XRD patterns indicate that the intensity of the ZnO (101) peak gradually increases with increasing concentration of Eu³⁺ ions, with an additional Eu₂O₃ (222) diffraction peak appearing in samples with Eu³⁺ concentrations above 2 wt%. All of the phosphor samples, irrespective of the concentration of Eu³⁺ ion, show a dominant red emission centered at 612 nm, which originates from the ⁵D0 → ⁷F₂ electric dipole transition of the Eu³⁺ ion. This suggests that the Eu³⁺ ions are mainly situated in the asymmetry centers of the host lattice.