Detail publikace

Syntéza nanokrystalického oxidu ceričitého dopovaného Sm,Gd a Y v přítomnosti ultrazvuku a za hydrotermálních podmínek

ČÁSTKOVÁ, K. CIHLÁŘ, J.

Český název

Syntéza nanokrystalického oxidu ceričitého dopovaného Sm,Gd a Y v přítomnosti ultrazvuku a za hydrotermálních podmínek

Anglický název

Synthesis of nanocrystalline ceria doped by Sm, Gd and Y in presence of ultrasound and under hydrothermal conditions

Typ

článek ve sborníku ve WoS nebo Scopus

Jazyk

cs

Originální abstrakt

In the present study, the hydrothermal conditions and ultrasound fields were used for synthesis of nanocrystalline ceria doped by Sm, Gd and Y. The aim of this work was study of the effect of reaction conditions on phase composition, microstructure, particle size distribution, surface area and agglomeration of the product particles. Doped ceria (molar ratio CeO2/Re2O3=9) was precipitated from an isopropanol solution of nitrates in the presence of the mixture of ammonium hydroxide and hydroperoxide. In the first type of experiment made in/without presence of ultrasound field (60-70C/1h) the recieved precipitates were hydrothermal treated at 150C for 4 hours (marked UN-untreated, US-ultrasound, HT-hydrothermal treated, US+HT-ultrasound+hydrothermal treated). In the second type of exepriment the precipitations were performed under hydrothermal conditions at 150C for 4 hours (marked HTP-hydrothermal precipitation). The final products were repeatly washed by isopropanol. The alcohol suspensions were used for determination of particle size distribution and microstructure of the product. Dried product (100C/2h) was analysed by RTG diffraction (phase composition and crystallinity size) and BET (surface area). In all synthesized products the only crystalline monophase doped ceria – Ce0,8ReO,2O1,9 (corresponding to molar ratio of reactants) was found. Phase composition was not affected by reaction conditions (by reaction temperature respectively) and crystallite size of the products was comparable (about 2,0-5,0 nm). It was found that ultrasound had an effect on the agglomeration of particles. Whereas the agglomerate size of UN and HT products was 2,2-2,5 ěm, the agglomerate size of US and US+HT synthesed products was 0,7-1,6 ěm. This effect was confirmed by the HTP products, which agglomerate size was to 3,9 ěm. Hydrothermal conditions had no effect on the agglomeration of the particles. Surface area of ceria particles (US and US+HT) was 49,5-86,0 m2/g. These results agree with determined crystallite size of these products.

Český abstrakt

In the present study, the hydrothermal conditions and ultrasound fields were used for synthesis of nanocrystalline ceria doped by Sm, Gd and Y. The aim of this work was study of the effect of reaction conditions on phase composition, microstructure, particle size distribution, surface area and agglomeration of the product particles. Doped ceria (molar ratio CeO2/Re2O3=9) was precipitated from an isopropanol solution of nitrates in the presence of the mixture of ammonium hydroxide and hydroperoxide. In the first type of experiment made in/without presence of ultrasound field (60-70C/1h) the recieved precipitates were hydrothermal treated at 150C for 4 hours (marked UN-untreated, US-ultrasound, HT-hydrothermal treated, US+HT-ultrasound+hydrothermal treated). In the second type of exepriment the precipitations were performed under hydrothermal conditions at 150C for 4 hours (marked HTP-hydrothermal precipitation). The final products were repeatly washed by isopropanol. The alcohol suspensions were used for determination of particle size distribution and microstructure of the product. Dried product (100C/2h) was analysed by RTG diffraction (phase composition and crystallinity size) and BET (surface area). In all synthesized products the only crystalline monophase doped ceria – Ce0,8ReO,2O1,9 (corresponding to molar ratio of reactants) was found. Phase composition was not affected by reaction conditions (by reaction temperature respectively) and crystallite size of the products was comparable (about 2,0-5,0 nm). It was found that ultrasound had an effect on the agglomeration of particles. Whereas the agglomerate size of UN and HT products was 2,2-2,5 ěm, the agglomerate size of US and US+HT synthesed products was 0,7-1,6 ěm. This effect was confirmed by the HTP products, which agglomerate size was to 3,9 ěm. Hydrothermal conditions had no effect on the agglomeration of the particles. Surface area of ceria particles (US and US+HT) was 49,5-86,0 m2/g. These results agree with determined crystallite size of these products.

Anglický abstrakt

In the present study, the hydrothermal conditions and ultrasound fields were used for synthesis of nanocrystalline ceria doped by Sm, Gd and Y. The aim of this work was study of the effect of reaction conditions on phase composition, microstructure, particle size distribution, surface area and agglomeration of the product particles. Doped ceria (molar ratio CeO2/Re2O3=9) was precipitated from an isopropanol solution of nitrates in the presence of the mixture of ammonium hydroxide and hydroperoxide. In the first type of experiment made in/without presence of ultrasound field (60-70C/1h) the recieved precipitates were hydrothermal treated at 150C for 4 hours (marked UN-untreated, US-ultrasound, HT-hydrothermal treated, US+HT-ultrasound+hydrothermal treated). In the second type of exepriment the precipitations were performed under hydrothermal conditions at 150C for 4 hours (marked HTP-hydrothermal precipitation). The final products were repeatly washed by isopropanol. The alcohol suspensions were used for determination of particle size distribution and microstructure of the product. Dried product (100C/2h) was analysed by RTG diffraction (phase composition and crystallinity size) and BET (surface area). In all synthesized products the only crystalline monophase doped ceria – Ce0,8ReO,2O1,9 (corresponding to molar ratio of reactants) was found. Phase composition was not affected by reaction conditions (by reaction temperature respectively) and crystallite size of the products was comparable (about 2,0-5,0 nm). It was found that ultrasound had an effect on the agglomeration of particles. Whereas the agglomerate size of UN and HT products was 2,2-2,5 ěm, the agglomerate size of US and US+HT synthesed products was 0,7-1,6 ěm. This effect was confirmed by the HTP products, which agglomerate size was to 3,9 ěm. Hydrothermal conditions had no effect on the agglomeration of the particles. Surface area of ceria particles (US and US+HT) was 49,5-86,0 m2/g. These results agree with determined crystallite size of these products.

Klíčová slova anglicky

hydrothermal synthesis, ultrasound synthesis, doped ceria

Rok RIV

2003

Vydáno

01.01.2002

Nakladatel

VUT v Brně, FSI

Místo

Ostrava

ISBN

80-7329-027-8

Kniha

Proceedings of the National Conference Nano 02

Číslo edice

první

Počet stran

4

BIBTEX


@inproceedings{BUT7258,
  author="Klára {Částková} and Jaroslav {Cihlář},
  title="Syntéza nanokrystalického oxidu ceričitého dopovaného Sm,Gd a Y v přítomnosti ultrazvuku a za hydrotermálních podmínek",
  booktitle="Proceedings of the National Conference Nano 02",
  year="2002",
  month="January",
  publisher="VUT v Brně, FSI",
  address="Ostrava",
  isbn="80-7329-027-8"
}