Effect of air annealing on properties of maghemite nanoparticles produced by radiation-chemical method\n

0574239 - ÚFM 2024 RIV GB eng J - Článek v odborném periodiku
Ilves, V. G. - Pizúrová, Naděžda - Korusenko, P. M. - Sokovnin, S. Yu. - Balezin, M.E. - Gerasimov, A. S. - Uimin, M. A. - Zuev, M. G. - Vasin, A. A.
Effect of air annealing on properties of maghemite nanoparticles produced by radiation-chemical method
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Ceramics International. Roč. 49, č. 15 (2023), s. 25414-25426. ISSN 0272-8842. E-ISSN 1873-3956
Grant CEP: GA ČR GC21-31852J
Institucionální podpora: RVO:68081723
Klíčová slova: Maghemite and hematite nanoparticles * Radiation-chemical method * Annealing in air
Obor OECD: Nano-materials (production and properties)
Impakt faktor: 5.2, rok: 2022
Způsob publikování: Omezený přístup
https://www.sciencedirect.com/science/article/pii/S0272884223013275?via%3Dihub

Amorphous-crystalline nanoparticles (NPles) of maghemite (gamma-Fe2O3) were successfully prepared by a radiation-chemical method using a precursor-heptahydrate of iron (II) sulfate. Synthesized NPles were quasi-spherical agglomerates 200-300 nm in size with an uneven surface covered with thin, porous, randomly oriented, elongated plates of irregular shape, with sharp vertices. The amorphous component of NPles included ultra-fine NPles maghemite about 2 nm in size. Stepwise annealing of the original nanopowder (NP) in air showed a phase transformation of NPles along the following path: maghemite + amorph (RT-150 degrees C) -> amorph (200-500 degrees C) -> hematite (570-1050 degrees C). The hematite NP produced after annealing at a temperature of 575 degrees C showed good texture characteristics: the specific surface area (SSA) increased from 21 to 36.8 m(2)/g, the pore volume increased from 0.04 to 0.15 cm(3)/g, while maintaining the particle nanosize of not more than 38 nm. X-ray photoelectron spectroscopy (XPS) showed the presence of the following elements on the surface of the synthesized NPles -S, C, O, Fe and N (N only in the original sample S0) and increased O-Fe bond with an increase in annealing temperature. The paramagnetic properties of the studied NPles indicate the prospect of their use as contrast agents in magnetic resonance imaging (MRI).
Trvalý link: https://hdl.handle.net/11104/0344577