Photocatalytic activity of anatase–nickel ferrite heterostructures

The simple co-precipitation route was used to couple commercial TiO2 anatase nanopowder with nickel ferrite (NiFe2O4). The morphology and the crystalline structure of composite nanoparticles were characterised by TEM, N2 adsorption-desorption, XRD and Rietveld refinement, XPS and XAS. The optical and magnetic properties were investigated. After co-precipitation NiFe2O4 nanoparticles, composed of spinel ferrite crystal phase, were formed on the surface of TiO2 anatase nanopowder. The TiO2/NiFe2O4 composite oxide demonstrated large specific surface area, high visible light absorption efficiency and efficient charge carrier separation, compared to pristine anatase TiO2 or pristine NiFe2O4, representatively. The obtained TiO2/NiFe2O4 composite oxides, with different nickel ferrite contents (5, 10, 25, 50 and 75 wt%) showed decent visible light photocatalytic efficiency, up to three times higher than pure anatase or pure NiFe2O4. However, TiO2/NiFe2O4 composite oxides did not demonstrate high magnetic properties.