Role of cerium (Ce) dopant on structural, optical and photocatalytic properties of MgO nanoparticles by wet chemical route

Ce doped MgO nanoparticles with various doping concentrations of cerium ion were prepared by the sol-gel method. Both pure and Ce doped MgO nanoparticles were characterized by powder X-ray diffraction (XRD), Scanning electron microscope (SEM), Field emission scanning electron microscope, Energy-dispersive X-ray spectroscopy, UV-Vis diffuse reflectance spectroscopy, and Photoluminescence spectra analysis. XRD and SEM results suggest that both pristine and Ce doped MgO nanoparticles were in face centered cubic structure with individual spherical shaped nanoparticles with average particles sizes in the range of 20-30 nm. The band gap energy of pure MgO was significantly reduced from 3.81 eV to 3.22 eV. The Ce doped MgO catalyst showed outstanding photocatalytic degradation activity such as high efficiency (95%) and high stability (only loss 3.5%) towards phenol dye under visible light irradiation. The improved photocatalytic mechanism of MgO by Ce doping is also discussed.