Fabrication and Characterization of CoFe2O4-Polymer Nanocomposite Thin-Films

Magnetic cobalt ferrite nanoparticles provide a pathway towards nanocomposites, due to the ability to fabricate particle-matrix thin films in the submicron range. In this work flexible particulate 0-3 type thin-films, composed of magnetic CoFe2O4 particles (8-18 nm) and ferroelectric poly(vinylidene fluoride-co-hexafluoropropene) (P(VDF-HFP)) polymer, have been fabricated via multiple spin-coating. The thickness of the thin-films was controlled in the range of 500 nm to 1.2 μm, with magnetic particles dispersively embedded in the polymer matrix. Structural information was analyzed by TEM, XRD, HRTEM and SEM. The dielectric and magnetic properties of the cobalt ferrite/copolymer thin films are systematically investigated. The nanocomposite thin films exhibit composition-dependent effective permittivity and loss tangent, as well as temperature and composition-dependent specific saturation magnetization (Ms). The coercivity (Hc) was not affected by the composite’s composition. These films have great potential in smart magnetic devices and biomagnetic applications.