Structure and luminescence of HfO2-codoped Gd2O3:Eu phosphors

This work presents the effects of Hf doping on structure and spectroscopic properties of Gd2O3:Eu phosphors. It was found that the lattice of Gd2O3:Eu phosphors transforms from monoclinic to cubic when the Hf4+ ions are doped, and cell sizes decrease with the increase of Hf-doping level. The phosphors showed decreased photoluminescence intensity after Hf4+ doping. Competitive absorption of interstitial oxygen and local symmetry of Eu3+ sites are proposed for such a decrease.