Effect of europium doping on the microstructural, optical and photocatalytic properties of ZnO nanopowders

Europium (Eu) doped zinc oxide (ZnO) nanopowders were successfully synthesized by the solid-state reaction method for three different weight percentages (3%, 5% and 7%) and investigated by using X-ray Powder Diffraction (XRD), Thermo-gravimetric analysis (TGA), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Fourier Transform Infrared (FTIR) Spectroscopy. Structural investigations showed that the synthesized nanopowders have a high purity of wurtzite structure, characterized by grain size in the range of 20–65 nm. The UV-Vis spectroscopy study shows an increase in the optical absorption from 35 to 70% and a decrease in the band gap from 3.23 to 3.14 eV. The photocatalytic degradation efficiency of the synthesized composite was studied experimentally for the degradation of the MB dye by hydrogen peroxide under UV-Vis irradiation and pH ∼ 6.4. A decolorization of 38% was reached after 30 min of light exposure. The photoluminescence study exhibits a violet, green, and blue emissions whose intensity and wavelength could be controlled by choosing the adequate Eu-doping percentage.