Synthesis of nanocomposite γ-Fe2O3@SiO2@TiO2 doped with copper and nickel and investigation of its antibacterial properties in aquatic ecosystems

In this study, γ-Fe2O3 magnetic nanoparticles were synthesized via solvothermal method and after coating a silica layer (SiO2), TiO2 nanoparticles were used as a core to grow on the outer surface to get γ-Fe2O3@SiO2@TiO2 nanocomposite. In order to increase the photocatalytic efficiency, the obtained nanocomposite was doped with different metals such as copper and nickel. Different techniques such as XRD, SEM and FTIR were used to characterize and determine the properties of the produced nanoparticles. Antibacterial activities of the doped magnetic nanocomposites on the gram-positive S. aureus and gram-negative E.coli strains were investigated by disc diffusion and minimum inhibitory concentration methods. The results obtained from the inhibition amount of the bacterial growth showed that the γ-Fe2O3@SiO2@TiO2 nanocomposite has high antibacterial properties which could be increased by doping with copper and nickel metals. The amounts of 15 mg were selected as the minimum inhibition amount of the growth of the bacteria for the two photocatalysts consisting of copper and nickel. It can be concluded that the synthesized nanocomposites with photocatalytic properties have a suitable potential to remove harmful bacteria from the aquatic environments.