Effect of the Eu³⁺ (x = 0, 1, 2 and 3 mol%) doped Zn_2−xTiO₄ and Zn₂Ti_1−xO₄ obtained by complex polymerization method: photoluminescent and photocatalytic properties

In this work, Zn₂Eu_xTi_1−xO₄ and Zn_2−xEu_xTiO₄ (x = 0, 1, 2 and 3 mol%) powders were synthesized by complex polymerization method (CPM) and calcined at 1000 °C for 4 h. The powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–Vis spectroscopy in the visible region and photoluminescence properties (PL). The photocatalytic properties were estimated by degradation of methylene blue (MB) dye when irradiated by UV lamps. X-ray diffraction results demonstrated the existence of Zn₂TiO₄ as primary phase and ZnO with secondary phase. According to diffractograms, the crystallite size varied between 49 and 67 nm. The Eu³⁺ ions introduction provides increased absorption in visible region, but the band-gap remains practically constant. In samples were observed an increased in photocatalysis with the increase in europium concentration, while in the Zn₂Eu_xTi_1−xO₄ samples, photocatalysis was reduced to europium concentrations greater than 1%. Eu³⁺ doped Zn₂TiO₄ provided a photoluminescent intensity increasing. CIE chromaticity coordinates confirm emission in the red region of the phosphor.