Nuclear magnetic resonance in hexaferrite/maghemite composite nanoparticles

0450138 - FZÚ 2016 RIV PL eng C - Conference Paper (international conference)
Kříšťan, P. - Hondlík, O. - Štěpánková, H. - Chlan, V. - Kouřil, K. - Řezníček, R. - Pollert, Emil - Veverka, Pavel
Nuclear magnetic resonance in hexaferrite/maghemite composite nanoparticles.
Acta Physica Polonica A, vo. 127, č. 2. Warszawa: Polish Academy of Sciences, 2015, s. 514-516. ISSN 0587-4246. E-ISSN 1898-794X.
[The European Conference PHYSICS OF MAGNETISM 2014/PM'14/. Poznań (PL), 23.06.2014-27.06.2014]
Institutional support: RVO:68378271
Keywords : nuclear magnetic resonance and relaxation * ferrimagnetics * fine-particle systems * nanocrystalline materials * magnetic oxides * inorganic compounds
Subject RIV: BM - Solid Matter Physics ; Magnetism

Due to their bio-compatibility and non-toxicity, iron oxides are suitable for magnetic drug delivery or as materials for hyperthermia. Compounds of spinel structure (mag-netite/maghemite) are most frequently used, however, the desired magnetic properties can be reached by combining more phases (e.g., maghemite and hexaferrite) into a composite material. We employed NMR to investigate strongly inhomogeneous nanoparticle composites. Frequency-swept 57Fe NMR spectra of nanoparticle samples containing maghemite, hematite and M-phase of strontium hexaferrite were measured in zero external magnetic field at 4.2 K. Utilizing differences in optimal excitation field strengths and in relaxation times, we were able to resolve NMR signal assigned to hexagonal phase from signal which showed features attributed to maghemite.
Permanent Link: http://hdl.handle.net/11104/0251527