Low temperature superparamagnetic nanocomposites obtained by Fe(acac)(3)-SiO2-PVA hybrid xerogel thermolysis

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F16%3A10337494" target="_blank" >RIV/00216208:11310/16:10337494 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.2298/PAC1604265I" target="_blank" >http://dx.doi.org/10.2298/PAC1604265I</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.2298/PAC1604265I" target="_blank" >10.2298/PAC1604265I</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Low temperature superparamagnetic nanocomposites obtained by Fe(acac)(3)-SiO2-PVA hybrid xerogel thermolysis

Popis výsledku v původním jazyce

Fe(acac)(3)/silica/PVA hybrid xerogel nanocomposite was obtained by one pot acid catalysed sol-gel synthesis using the homogeneous mixture of iron(III) acetylacetonate (Fe(acac)(3)), tetraethylorthosilicate (TEOS), and polyvinyl alcohol (PVA). Nominal composition ratio of iron oxide/silica was 15/85 (weight percent). Nitric acid was used as catalyst. Another sample of Fe(acac)(3)/silica xerogel without PVA addition was prepared in the similar processing conditions. Based on thermal analysis studies, the thermal behaviour of both xerogel samples was unveiled and it allowed choosing the optimal calcination temperatures in order to obtain iron oxide silica magnetic nanocomposite samples. The two xerogel (with and without PVA) samples were thermally treated, in air, at 220, 260 and 300 degrees C and characterized by different techniques. XRD investigations revealed phase composition evolution with calcination temperature, from cubic spinel phase (maghemite) to hexagonal stable hematite containing nanocomposite of 10-20 nm average crystallite size. These findings were confirmed by Mossbauer spectroscopy. Up to 300 degrees C, the surface area and total pores volume increased with temperature for all samples. By calcination at the same temperature, the hybrid xerogel containing PVA resulted in significantly higher magnetization and free volume values in comparison with the sample without PVA.

Název v anglickém jazyce

Low temperature superparamagnetic nanocomposites obtained by Fe(acac)(3)-SiO2-PVA hybrid xerogel thermolysis

Popis výsledku anglicky

Fe(acac)(3)/silica/PVA hybrid xerogel nanocomposite was obtained by one pot acid catalysed sol-gel synthesis using the homogeneous mixture of iron(III) acetylacetonate (Fe(acac)(3)), tetraethylorthosilicate (TEOS), and polyvinyl alcohol (PVA). Nominal composition ratio of iron oxide/silica was 15/85 (weight percent). Nitric acid was used as catalyst. Another sample of Fe(acac)(3)/silica xerogel without PVA addition was prepared in the similar processing conditions. Based on thermal analysis studies, the thermal behaviour of both xerogel samples was unveiled and it allowed choosing the optimal calcination temperatures in order to obtain iron oxide silica magnetic nanocomposite samples. The two xerogel (with and without PVA) samples were thermally treated, in air, at 220, 260 and 300 degrees C and characterized by different techniques. XRD investigations revealed phase composition evolution with calcination temperature, from cubic spinel phase (maghemite) to hexagonal stable hematite containing nanocomposite of 10-20 nm average crystallite size. These findings were confirmed by Mossbauer spectroscopy. Up to 300 degrees C, the surface area and total pores volume increased with temperature for all samples. By calcination at the same temperature, the hybrid xerogel containing PVA resulted in significantly higher magnetization and free volume values in comparison with the sample without PVA.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

JH - Keramika, žáruvzdorné materiály a skla

OECD FORD obor

—

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

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

Název periodika

Processing and Application of Ceramics

ISSN

1820-6131

e-ISSN

—

Svazek periodika

10

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

CS - Srbsko a Černá Hora

Počet stran výsledku

11

Strana od-do

265-275

Kód UT WoS článku

000393209100009

EID výsledku v databázi Scopus

2-s2.0-85007504636