Detail publikace

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.

Anglický název

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

Typ

Článek recenzovaný mimo WoS a Scopus

Jazyk

en

Originální abstrakt

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.

Vydáno

2006-01-01

Nakladatel

Elsevier Science

ISSN

0955-2219

Ročník

26

Číslo

14

Strany od–do

2999–3004

Počet stran

6

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"
}