Publication detail

Synthesis, structure and oxygen thermally programmed desorption spectra of La1-xCaxAlyFe1-yO3-d perovskites

CIHLÁŘ, J. DEL FAVERO, D. CIHLÁŘ, J. BUCHAL, A. VAN HERLE, J.

Original Title

Synthesis, structure and oxygen thermally programmed desorption spectra of La1-xCaxAlyFe1-yO3-d perovskites

Type

journal article - other

Language

English

Original Abstract

Perovskites La1-xCaxAlyFe1-yO3-d (x, y = 0 to 1) were prepared by high-temperature solid-state synthesis based on mixtures of oxides produced by colloidal milling. The XRD analysis showed that perovskites La0.5Ca0.5AlyFe1-yO3-d with a high Fe content (1 - y = 0.8-1.0) were of orthorhombic structure, perovskites with a medium Fe content (1 - y = 0.8-0.5) were of rhombohedral structure, and perovskite with the lowest Fe content (1 - y = 0.2) were of cubic structure. Thermally programmed desorption (TPD) of oxygen revealed that chemical desorption of oxygen in the temperature range from 200 to 1000 degC had proceeded in the two desorption peaks. The low-temperature alfa-peak (in the 200-550 degC temperature range) was brought about by oxygen liberated from oxygen vacancies; the high-temperature beta-peak (in the 550-1000 degC temperature range) corresponded to the reduction of Fe4+ to Fe3+. The chemidesorption oxygen capacity increased with increasing Ca content and decreased with increasing Al content in the perovskites. The Al3+ ions restricted, probably for kinetic reasons, the reduction of Fe4+ and the high-temperature oxygen desorption associated with it.

Key words in English

Perovskites; membranes; X-ray methods; powders-solid state reaction; chemisorption

Authors

CIHLÁŘ, J.; DEL FAVERO, D.; CIHLÁŘ, J.; BUCHAL, A.; VAN HERLE, J.

RIV year

2006

Released

1. 1. 2006

Publisher

Elsevier Science

ISBN

0955-2219

Periodical

Journal of the European Ceramic Society

Year of study

26

Number

14

State

United Kingdom of Great Britain and Northern Ireland

Pages from

2999

Pages to

3004

Pages count

6

URL

http://www.sciencedirect.com

BibTex

@article{BUT43557,
  author="Jaroslav {Cihlář} and David {Del Favero} and Jaroslav {Cihlář} and Antonín {Buchal} and Jan {Van herle}",
  title="Synthesis, structure and oxygen thermally programmed desorption spectra of La1-xCaxAlyFe1-yO3-d perovskites",
  journal="Journal of the European Ceramic Society",
  year="2006",
  volume="26",
  number="14",
  pages="2999--3004",
  issn="0955-2219",
  url="http://www.sciencedirect.com"
}