MS-12-P-3406 Characterization of BaTiO3/CoFe2O4 thin films prepared by sol-gel process

Nanocomposites formed by ferrimagnetic and ferroelectric materials are a multiferroic material in which magnetoelectric coupling occurs via piezoelectricity and magnetostriction phenomena. These nanocomposites have a variety of applications in tunable microwave devices using electric control of spin wave propagation or new magnetic memories in which the magnetic response is controlled by electric field. Sol-gel process has been an efficient method to produce this kind of thin films due to the good control of the sample morphology, texture, structure, and composition, which can be attained by monitoring in the physical-chemistry parameters of the precursor solution and of the deposition process

In this work, transparent and homogeneous thin films of barium titanate interleaved with cobalt ferrite were prepared by sol–gel method using dip-coating process. The BaTiO3 solution was prepared using tetraisopropyl orthotitanate, alcohol, and barium acetate. The CoFe2O4 solution was obtained by diluting cobalt nitrate and iron (III)-acetyl-acetonat in acidified aqueous solution. The nanocomposite films were dried in air after each dipping and heated at 700 oC for 10 min to convert the amorphous films into crystalline oxides. The samples were characterized by low angle X-ray diffraction (XRD), UV-vis spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and scanning force microscopy (AFM/MFM/PFM).

The nanocomposite films were formed by tetragonal barium titanate particles measuring between 10 and 25 nm, interfacing cubic ferrite cobalt particles measuring between 3 and 10 nm, providing a magnetoelectric coupling. The films showed magnetic and piezoelectric properties measured by magnetic and piezoresponse force microscopy.