Ni-TiO.sub.2./sub. nanocomposite films and their magnetic properties

0464460 - FZÚ 2017 RIV NL eng J - Journal Article
Vokoun, David - Svatuška, Michal - Olejníček, Jiří - Kohout, Michal - Drahokoupil, Jan - Rameš, Michal - Vejpravová, Jana - Mantlíková, Alice - Fekete, Ladislav - Kopeček, Jaromír - Klimša, Ladislav - Heczko, Oleg
Ni-TiO₂ nanocomposite films and their magnetic properties.
Physica B-Condensed Matter. Roč. 503, Dec (2016), s. 44-50. ISSN 0921-4526. E-ISSN 1873-2135
R&D Projects: GA ČR GC15-13174J; GA MŠMT LO1409; GA MŠMT LM2015088
Grant - others:FUNBIO(XE) CZ.2.16/3.1.00/21568
Institutional support: RVO:68378271
Keywords : Ni nanoparticles * sputtering * NiTi oxidation * heat treatment * magnetic anisotropy * superparamagnetic state
Subject RIV: JI - Composite Materials
Impact factor: 1.405, year: 2016

We have demonstrated a method for preparing nickel nanoparticles in TiO2 matrix films, 500–900nm thick, using magnetron sputtering followed by a heat treatment at temperatures 723–773 K for 1 h in various gas atmospheres. The X-ray diffraction indicated that the size of Ni crystallites was 4–6 nm depending on the heat treatment conditions. Magnetic force and scanning electron microscopy studies show clustering the nanoparticles to size of order hundreds of nm arranged in a shape of nanopillars separated byTiO2. The above mentioned clustering results in a magnetic anisotropy as indicated from the loops of the magnetic moment – magnetic field curves in the perpendicular and parallel directions. Some of the prepared nanocomposite samples exhibit different magnetic behavior within the perpendicular and parallel directions for |μ0H|>0.6 T, presumably due to the presence of antiferromagnetic oxides.
Permanent Link: http://hdl.handle.net/11104/0264071