Impact of silica environment on hyperfine interactions in ε-Fe2O3 nanoparticles
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F16%3A10332324" target="_blank" >RIV/00216208:11320/16:10332324 - isvavai.cz</a>
Alternative codes found
RIV/68378271:_____/16:00469997 RIV/61388980:_____/16:00469997
Result on the web
<a href="http://dx.doi.org/10.1007/s10751-016-1356-8" target="_blank" >http://dx.doi.org/10.1007/s10751-016-1356-8</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1007/s10751-016-1356-8" target="_blank" >10.1007/s10751-016-1356-8</a>
Alternative languages
Result language
angličtina
Original language name
Impact of silica environment on hyperfine interactions in ε-Fe2O3 nanoparticles
Original language description
Magnetic nanoparticles have found broad applications in medicine, especially for cell targeting and transport, and as contrast agents in MRI. Our samples of ε-Fe2O3 nanoparticles were prepared by annealing in silica matrix, which was leached off and the bare particles were then coated with amorphous silica layers of various thicknesses. The distribution of particle sizes was determined from the TEM pictures giving the average size 20 nm and the thickness of silica coating ~5; 8; 12; 19 nm. The particles were further characterized by the XRPD and DC magnetic measurements. The nanoparticles consisted mainly of ε-Fe2O3 with admixtures of ~1%of the α-phase and less than 1% of the γ-phase. The hysteresis loops displayed coercivities of ~2 T at room temperature. The parameters of hyperfine interactions were derived from transmission Mossbauer spectra. Observed differences of hyperfine fields for nanoparticles in the matrix and the bare ones are ascribed to strains produced during cooling of the composite. This interpretation is supported by slight changes of their lattice parameters and increase of the elementary cell volume deduced from XRD. The temperature dependence of the magnetization indicated a two-step magnetic transition of the ε-Fe2O3 nanoparticles spread between ~85 K and ~150 K, which is slightly modified by remanent tensile stresses in the case of nanoparticles in the matrix. The subsequent coating of the bare particles by silica produced no further change in hyperfine parameters, which indicates that this procedure does not modify magnetic properties of nanoparticles.
Czech name
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Czech description
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Classification
Type
J<sub>x</sub> - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)
CEP classification
BM - Solid-state physics and magnetism
OECD FORD branch
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Result continuities
Project
<a href="/en/project/GA16-04340S" target="_blank" >GA16-04340S: Oxide nanomagnets, their properties and interactions with biological systems</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2016
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Hyperfine Interaction
ISSN
0304-3843
e-ISSN
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Volume of the periodical
2016
Issue of the periodical within the volume
237
Country of publishing house
NL - THE KINGDOM OF THE NETHERLANDS
Number of pages
10
Pages from-to
1-10
UT code for WoS article
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EID of the result in the Scopus database
2-s2.0-84995543338