Observation of surface effects in La-doped CoFe2O 4/SiO2 nanocomposites

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388980%3A_____%2F11%3A00440078" target="_blank" >RIV/61388980:_____/11:00440078 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1088/1757-899X/18/2/022015" target="_blank" >http://dx.doi.org/10.1088/1757-899X/18/2/022015</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1757-899X/18/2/022015" target="_blank" >10.1088/1757-899X/18/2/022015</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Observation of surface effects in La-doped CoFe2O 4/SiO2 nanocomposites

Popis výsledku v původním jazyce

In magnetism of nanoparticles, surface spin effects play a key role. The so-called spin canting at the surface leads either to lowering of saturation magnetization, or even to lack of saturation in high magnetic fields. The value of the saturation magnetization depends on cation distribution within the spinel network and on the spin canting angles. We have investigated structure and magnetic behavior of CoFe2O4 nanoparticles doped with La (Co1-xLaxFe2O4, x 0.05 - 0.5 and CoLaxFe2-xO4, x 0.05 - 0.2) embedded in amorphous silica matrix prepared by a sol-gel method. The samples were characterized using X-ray diffraction and TEM. The zero-field cooled and field cooled measurements of magnetization showed that the blocking temperature is well above the roomtemperature. The high coercivity was observed (up to 2 T at 10 K) and no saturation of the magnetization even in applied field of 7 T was obtained, suggesting considerable spin canting effects. Finally, the Mossbauer spectroscopy under m

Název v anglickém jazyce

Observation of surface effects in La-doped CoFe2O 4/SiO2 nanocomposites

Popis výsledku anglicky

In magnetism of nanoparticles, surface spin effects play a key role. The so-called spin canting at the surface leads either to lowering of saturation magnetization, or even to lack of saturation in high magnetic fields. The value of the saturation magnetization depends on cation distribution within the spinel network and on the spin canting angles. We have investigated structure and magnetic behavior of CoFe2O4 nanoparticles doped with La (Co1-xLaxFe2O4, x 0.05 - 0.5 and CoLaxFe2-xO4, x 0.05 - 0.2) embedded in amorphous silica matrix prepared by a sol-gel method. The samples were characterized using X-ray diffraction and TEM. The zero-field cooled and field cooled measurements of magnetization showed that the blocking temperature is well above the roomtemperature. The high coercivity was observed (up to 2 T at 10 K) and no saturation of the magnetization even in applied field of 7 T was obtained, suggesting considerable spin canting effects. Finally, the Mossbauer spectroscopy under m

Druh

D - Stať ve sborníku

CEP obor

CA - Anorganická chemie

OECD FORD obor

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Projekt

<a href="/cs/project/GAP108%2F10%2F1250" target="_blank" >GAP108/10/1250: Multifunkční nanočástice: pokročilé metody přípravy a studium jejich fyzikálních vlastností</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2011

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

IOP conference series: Materials science and engineering

ISBN

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ISSN

1757-8981

e-ISSN

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Počet stran výsledku

4

Strana od-do

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Název nakladatele

IOP Publishing

Místo vydání

Bristol

Místo konání akce

Osaka

Datum konání akce

14. 11. 2010

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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