a 2009

NANOSCOPIC COBALT FERRITE PARTICLES BY SONOLYSIS OF METAL ACETYLACETONATE COMPLEXES

OSTŘÍŽEK, Petr, Petr BEZDIČKA, Zdeněk MORAVEC and Jiří PINKAS

Basic information

Original name

NANOSCOPIC COBALT FERRITE PARTICLES BY SONOLYSIS OF METAL ACETYLACETONATE COMPLEXES

Name in Czech

Příprava nanoskopických částic kobaltových ferritů sonolýzou acetylacetonátových komplexů kovů

Name (in English)

NANOSCOPIC COBALT FERRITE PARTICLES BY SONOLYSIS OF METAL ACETYLACETONATE COMPLEXES

Authors

OSTŘÍŽEK, Petr (203 Czech Republic, belonging to the institution), Petr BEZDIČKA (203 Czech Republic), Zdeněk MORAVEC (203 Czech Republic, belonging to the institution) and Jiří PINKAS (203 Czech Republic, guarantor, belonging to the institution)

Edition

ChemZi, 2009

Other information

Language

Czech

Type of outcome

Konferenční abstrakt

Field of Study

10402 Inorganic and nuclear chemistry

Country of publisher

Slovakia

Confidentiality degree

není předmětem státního či obchodního tajemství

RIV identification code

RIV/00216224:14310/09:00051212

Organization unit

Faculty of Science

ISSN

Keywords (in Czech)

nanočástice; kobalt; ferrity; sonolýza; acetylacetonáty

Keywords in English

nanoparticles; cobalt; ferrites; sonolysis; acetylacetonates

Tags

Tags

International impact
Změněno: 5/4/2012 10:21, Iva Klímová

Abstract

V originále

Previously we studied the preparation of Fe2O3 and Co3O4 nanoparticles by sonolysis of 2,4-pentanedionato complexes, M(acac)n, M = Fe, Co. Now we continue this research with the preparation of mixed metal oxide CoFe2O4. Sonochemical decompositon of mixtures of M(acac)n by high intensity ultrasound lead to amorphous Co ferrite nanoparticles containing organic matrix. The sonochemical reactivity of precursors was: Co(acac)2 > Fe(acac)3 > Co(acac)3. The XRD data showed that phase-pure CoFe2O4 were obtained for Co:Fe ratios of 1:1.3 to 1:2.0. Variable amounts of added water allowed control of the organics content and the BET surface area (up to 218 m2 g-1). SEM was used to examine the particle shape, size, and size distribution. The organic groups present in the powders were identified by IR and MS as acetate groups. TEM study showed the amorphous state of the sonochemical oxide product and its crystallization above 300 oC in agreement with the results of TG/DSC. The HT-XRD also revealed the spinel crystallization on heating. A small particle size below 20 nm of the crystalline CoFe2O4 is retained up to 600 oC. The delayed crystal growth is ascribed to the protective action of a thin surface layer of pyrolyzed organics.

In English

Previously we studied the preparation of Fe2O3 and Co3O4 nanoparticles by sonolysis of 2,4/pentanedionato complexes, M(acac)n, M = Fe, Co. Now we continue this research with the preparation of mixed metal oxide CoFe2O4. Sonochemical decompositon of mixtures of M(acac)n by high intensity ultrasound lead to amorphous Co ferrite nanoparticles containing organic matrix. The sonochemical reactivity of precursors was: Co(acac)2 > Fe(acac)3 > Co(acac)3. The XRD data showed that phase-pure CoFe2O4 were obtained for Co:Fe ratios of 1:1.3 to 1:2.0. Variable amounts of added water allowed control of the organics content and the BET surface area (up to 218 m2 g-1). SEM was used to examine the particle shape, size, and size distribution. The organic groups present in the powders were identified by IR and MS as acetate groups. TEM study showed the amorphous state of the sonochemical oxide product and its crystallization above 300 oC in agreement with the results of TG/DSC. The HT-XRD also revealed the spinel crystallization on heating. A small particle size below 20 nm of the crystalline CoFe2O4 is retained up to 600 oC. The delayed crystal growth is ascribed to the protective action of a thin surface layer of pyrolyzed organics.

Links

MSM0021622410, plan (intention)
Name: Fyzikální a chemické vlastnosti pokročilých materiálů a struktur
Investor: Ministry of Education, Youth and Sports of the CR, Physical and chemical properties of advanced materials and structures