Electrochemical Preparation of Ni and Fe Hydroxide/Oxide Films Using Polyethylenimine

Composite films consisting of Fe hydroxide, Ni hydroxide and polyethylenimine (PEI) were obtained by the combined electrolytic-electrophoretic deposition method. The proposed method for PEI charging and deposition is based on the use of cationic polymer-metal ion complexes. Cathodic deposits were obtained on Pt and Ag substrates. By varying both the concentration of PEI in solutions and the deposition time, the amount of material deposited and its composition can be varied. The method was used to fabricate NiFe 2 O 4 films. The deposits were studied by thermogravimetric analysis, X-ray diffraction analysis and SEM. The mechanism of electrochemical intercalation of PEI into hydroxide deposits is discussed.