Hydrothermal preparation of a protective Fe3O4 film on Fe foil

Abstract A ‘green’ hydrothermal process was used to prepare Fe 3 O 4 film on bare Fe foil. X-ray diffraction and scanning electron microscopy (SEM) were employed to characterize the film. The results showed that the film was composed of fine particles with regularly truncated cubic morphology. Electrochemical properties of the coating were investigated by anodic polarization test and electrochemical impedance spectroscopy (EIS). Anodic polarization results indicated that compared with bare Fe foil, the corrosion potential of coated foil increased by 104.4 mV while its current density reduced by 0.11 mA cm −2 . EIS analysis showed that the corrosion resistance of Fe foil increased significantly after coating with Fe 3 O 4 film.