A novel nickel-doped photoactive nanocomposite materials for the application of wastewater treatment

Abstract

We have reported an efficient and novel nanocomposite structure of nickel (0.5 %, 1.0 %, 1.5 %, 2.0 % and 2.5 %) doped Fe3O4@rGO which is prepared by a simple chemical co-precipitation technique for degradation of methylene blue. In the current study, reduced graphene oxide (rGO) is chosen as the electron mediator for NiFe3O4/rGO nanocomposite catalyst to construct a binary photocatalytic system. The analysis of structural and optical properties supports their nano size, formation of nanocomposite material, doping of nickel ions into the characteristic inverse spinel cubic structure of Fe3O4 and the existence of synergistic effect between NiFe3O4 and rGO. Methylene blue was considered as a model dye during the investigation of the Photocatalytic activity of NiFe3O4/rGO. From the kinetic measurements, the reaction rate was predicted to play a key role in the process of degradation. This discussion also highlights the absorption peak extension towards the visible region and the energy band gap value decreases with increasing the nickel dopant concentration in novel NiFe3O4/rGO nanocomposite material. Transition metal doping significantly enhances the degradation efficiency and reduces the recombination rate of charge carriers which makes the NiFe3O4/rGO nanocomposite material a potential candidate for the degradation of methylene blue from wastewater. As indicated by all the nanocomposites, photocatalytic activity was higher than the pure Fe3O4 photocatalyst, and the highest photodegradation of 96.3 % MB within 30 min irradiation under visible light was shown by the 2.0 % of nickel-doped Fe3O4@rGO. In addition, the study examined the photodegradation process and photocatalytic reaction kinetics of MB.