Magnetic properties and morphology of ultra-small iron oxide nanoparticles

0561970 - ÚFM 2025 RIV GB eng C - Konferenční příspěvek (zahraniční konf.)
Pizúrová, Naděžda - Buršík, Jiří - Sojková, T. - Roupcová, Pavla - Schneeweiss, Oldřich
Magnetic properties and morphology of ultra-small iron oxide nanoparticles.
Journal of Physics: Conference Series. Vol. 2315. Bristol: IOP Publishing, 2022, č. článku 012023. ISSN 1742-6588.
[IC-CMTP6 International Conference on Competitive Materials and Technology Processes and 2nd European Conference on Silicon and Silica Based Materials /6./. Miskolc-Lillafüred (HU), 04.10.2021-08.10.2021]
Grant CEP: GA ČR GC21-31852J
Institucionální podpora: RVO:68081723
Klíčová slova: Iron oxides * Nanomagnetics * Nanoparticles * Synthesis (chemical)
Obor OECD: Nano-materials (production and properties)

Maghemite nanoparticles prepared with the modified synthesis method published by Sun et al. 2004 and followed by filtering to extract a sample of the smallest nanoparticle size were investigated. The 2-5 nm nanoparticles of monocrystalline and multi-twinned morphology without surface shells were observed. Superparamagnetic behavior was detected above the temperature of 40 K. An exchange bias loop shift of ~ 2 mT at 3 K after cooling with an external field of 3 T suggested a low influence of the surface spin disorder effect. Mössbauer spectroscopy confirmed the two phases with different blocking temperatures, the maghemite phase as well as a second one likely originating from the disordered surface component. © 2022 Institute of Physics Publishing. All rights reserved.
Trvalý link: https://hdl.handle.net/11104/0334404