Magnetically modified TiO2 powders – microstructure and magnetic properties

0453864 - ÚFM 2016 RIV NL eng C - Konferenční příspěvek (zahraniční konf.)
Žitovský, O. - Seidlerová, J. - Šafařík, Ivo - Luňáček, J. - Šafaříková, Miroslava - Kutláková Mamulová, K. - Jirásková, Yvonna
Magnetically modified TiO2 powders – microstructure and magnetic properties.
Physics Procedia. Vol.75. Amsterdam: Elsevier, 2015, s. 1450-1457. ISSN 1875-3892.
[International Conference on Magnetism /20./. Barcelona (ES), 05.07.2015-10.07.2015]
Institucionální podpora: RVO:68081723 ; RVO:67179843
Klíčová slova: Magnetically modified TiO2 * X-ray powder diffraction * microstructure * magnetic properties * vibrating sample magnetometer
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus; EI - Biotechnologie a bionika (UEK-B)

The anatase (TiO2) particles magnetically modified by iron oxides and prepared by an innovating technological procedure are studied from the viewpoint of microstructure and a complex analysis of magnetic behaviour at room and elevated temperatures. Scanning electron microscopy observations have yielded variable shapes of particles in the composite powder whereas the iron oxide particles of diameter bellow 1 μm were detected on the surface of the TiO2. The dominant magnetite (Fe3O4) accompanied by a small amount of maghemite (γ-Fe2O3) and/or hematite (α- Fe2O3) were analysed by X-ray powder diffraction. A relatively high saturation magnetization (3.38 Am2/kg), negative dipolar interactions, and the low values of reversible and irreversible part of magnetic susceptibility were found out from magnetic measurements at room temperature. During a thermomagnetic treatment the composite sample has been going through a few magnetic phase transitions and transforms into a fully paramagnetic state around 850 K. After its cooling to the room temperature an undesirable magnetic hardening of the sample has occurred.
Trvalý link: http://hdl.handle.net/11104/0255893