Magnetic nanocomposite thin films prepared by sol-gel process

Abstract

Cobalt ferrite composite thin films, CoFe 2 O 4 /SiO 2 , were prepared by sol-gel process, using tetraethylorthosilicate (TEOS) as a precursor for silica, and metallic nitrates as precursors for ferrite. The obtained dip-coated films thermally treated at 550, 750, and 950˚C were transparent, homogeneous and adherent. Their magnetic properties were measured from 2.5 K to 300 K using a SQUID magnetometer. Superparamagnetic behaviour was observed at room temperature and below a blocking temperature appears with coercivity values increasing with annealing temperature.

Wave Propagation in Nanodoped Films

“…Magnetic nano composite films are used specially to enhance the film coercivity [7][8][9][10][11]. that is their resistance to becoming demagnetized.…”

ELECTRON SPIN RESONANCE RESPONSE OF BaFe12O19 NANOPARTICLE EMBEDDED POLYDIVINYLBENZENE MAGNETIC FILM

“…Barium ferrite (BaFe12O19) nano composite particles have a great interest due to the extraordinary magnetic properties such as large magnetic saturation, high magnetic anisotropy, high coercive field [1][2][3][4][5]. The BaFe12O19, m-type hexagonal crystal structure, is a well-known great performance permanent magnetic material and recently has been studied in electromagnetic absorption, magnetic recording media and microwave devices [6].…”

Synthesis of cobalt ferrite in organic solvents

“…As examples, we can give the classic method of coprecipitation [1,2], in which the magnetic properties of particles are strongly dependent on the conditions of the subsequent heat treatment [3], electrochemical [4] and combustion methods [5], the thermal decomposition of organic complexes of cobalt and iron [6,7], the sol gel synthe sis that makes it possible to obtain the CoFe 2 O 4 nano particles in the bulk matrix (usually organic) or thin film [8], the citrate gel method [9], etc. A very prom ising preparation method for cobalt ferrite is hydro thermal synthesis [10,11], but it requires serious equipment design.…”