Synthesis, characterization and application of Nb2O5-doped zinc oxide for solar-based photodegradation of 4-chlorophenol

Abstract This project studied the development of niobium oxide-doped zinc oxide photocatalysts, aiming to increase the photocatalytic efficiency of zinc oxide (ZnO). Characterization results prove the existence of zinc oxide and niobium oxide (Nb2O5) in the developed material. The addition of niobium oxide caused an increase in specific surface area and a decrease in the gap energy of the material. The results of 4-chlorophenol photodegradation show that the modified material displayed higher photocatalytic activity than pure ZnO. The superior photocatalytic activity is derived from the morphological and structural properties of the modified material, as well as from the heterojunctions formed between the semiconductors. The greater efficiency of charge transfer in the Nb2O5-doped material is demonstrated by the electrochemical impedance spectroscopy.