Photocatalytic activity of Eu3+-doped ZnO nanorods synthesized via microwave assisted technique

The doped ZnO nanorods as a photocatalyst with different Eu contents were prepared by microwave assisted method and they were characterized by means of X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), UV-Vis spectroscopy, surface area Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The average crystallite size and band gap energy of Eu-doped ZnO were varied with the Eu content. The XRD pattern of Eu-doped ZnO indicated hexagonal crystal structure with an average crystallite size of 25 nm. The presence of europium with trivalent state and its doping successfully into the crystal lattice of ZnO matrix were confirmed by XPS technique. The photocatalytic activity of Eu-doped ZnO nanorods was evaluated for methyl orange degradation. The photocatalytic experiments showed ∼91% degradation of methyl orange over 0.2 mol.% Eu doped ZnO sample within 3 h under UV light (365 nm).

The band gap values of the photocatalyst decreased from 3.34 to 3.0 eV as doping of Eu contents were increased. The Eu doping in ZnO matrix acted as an electron scavenger, which prevented the recombination of electron-hole pairs on the surface of the photocatalyst. A 91% degradation of Methyl Orange was obtained over 0.2 mol.% Eudoped ZnO nanorods within three hours under UV light (365 nm)Figure optionsDownload as PowerPoint slide