Magnetic binary nanofillers

MORALES, NOE; GOYANES SILVIA; CHILIOTTE, CLAUDIO; BEKERIS, VICTORIA; RUBIOLO,GERARDO; CANDAL, ROBERTO

PHYSICA B - CONDENSED MATTER

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2012 vol. 407 p. 3203 - 3205

0921-4526

Magnetic binary nanofillers containing multiwall carbon nanotubes (MWCNT) and hercynite weresynthesized by Chemical Vapor Deposition (CVD) on Fe/AlOOH prepared by the sol-gel method. The catalyst precursor was fired at 450 1C, ground and sifted through different meshes. Two powders were obtained with different particle sizes: sample A (50 - 75 mm) and sample B (smaller than 50 mm). These powders are composed of iron oxide particles widely dispersed in the non-crystalline matrix of aluminum oxide and they are not ferromagnetic. After reduction process the powders are composed of a-Fe nanoparticles inside hercynite matrix. These nanofillers are composed of hercynite containing a-Fe nanoparticles and MWCNT. The binary magnetic nanofillers were slightly ferromagnetic. The saturation magnetization of the nanofillers depended on the powder particle size. The nanofiller obtained from powder particles in the range 50-75 mm showed a saturation magnetization 36% higher than the one formed from powder particles smaller than 50 mm. The phenomenon is explained in terms of changes in the magnetic environment of the particles as consequence of the presence of MWCNT.