Template free synthesis, characterization and application of nano ZnO rods for the photocatalytic decolourization of methyl orange

Zinc oxide (ZnO) nano rods were synthesized by utrasonication assisted chemical precipitation method without any templates. The influence of pH on the growth of ZnO rods was examined by adjusting the pH of the reaction mixture at values 7, 9 and 13. The as-synthesized rods were characterized by XRD, FT-IR, UV-DRS, SEM and Room Temperature Photoluminescence Spectroscopy. The photocatalytic activity of the synthesized ZnO rods was studied by photocatalytic decolourization of Methyl Orange (MO) dye in presence of UV (365 nm) light irradiation in aqueous solution. The effects of operational parameters such as initial concentration of the MO dye, amount of photocatalyst and initial pH of the dye solution were analyzed. The photocatalytic decolourization of MO dye was confirmed from the decrease in intensity of UV–vis absorption peaks at 464 nm due to lowering concentration of MO dye. Photocatalytic decolourization of MO dye followed pseudo-first order kinetics.