Preparation and characterization of NiFe2O4/NiO composite film via a single-source precursor route

NiFe2O4/NiO nanocomposite thin films have been successfully prepared through a facile route using nickel iron layered double hydroxide (NiFe–LDH) as a single-source precursor. This synthetic approach mainly involves the formation of NiFe–LDH film by casting the slurry of NiFe–LDH precursor on the α-Al2O3 substrate, followed by high-temperature calcination. The composition, microstructure and properties of the films were characterized in detail by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and vibrating sample magnetometer (VSM). The results indicate that NiFe2O4/NiO composite film was composed of granules with diameter less than 100 nm, and the thickness of the film was in the range 1–2 μm. The magnetization of the film can be tuned by alternating the Ni/Fe molar ratio of LDH precursor. In addition, the method developed should be easily extended to fabricate other MFe2O4/MO composite film systems with specific applications just by an appropriate combination of divalent/trivalent composition in the precursor of LDHs.