Synthesis, characterization and photocatalytic activities of Ag-N-codoped ZnO nanoparticles for degradation of methyl red

Abstract

Ag-N-codoped zinc oxide nanoparticles were synthesized by a one-step impregnation of Ag in  N-doped ZnO nanoparticles. The morphologies and structures of the as-synthesized nanomaterials were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-Vis spectrophotometric techniques. Photocatalytic degradation of methyl red dye using synthesized photocatalysts was studied under solar as well as UV irradiations. Modified zinc oxide photocatalysts showed higher photocatalytic activity compared to pure zinc oxide both under solar as well as UV irradiations.  Calcined zinc oxide shows better photocatalytic activity than commercial zinc oxide under both solar and UV irradiations. Highest catalytic activity of Ag-N co-doped zinc oxide (ANZ) among the undoped, Ag-doped and N-doped photocatalysts was attributed to the lower rate of recombination of the photogenerated electrons and holes as well as its lower band gap energy. Photocatalytic degradation of methyl red dye follows pseudo first order kinetics for all the nanoparticles so-obtained.

KEY WORDS: Nanoparticles, Photocatalysis, Zinc oxide, Impregnation, Methyl red

Bull. Chem. Soc. Ethiop. 2013, 27(2), 221-232

DOI: http://dx.doi.org/10.4314/bcse.v27i2.7