Methane combustion over B-site partially substituted perovskite-type LaFeO3 prepared by sol-gel method

doi:10.1016/S0926-860X(97)00003-3

Applied Catalysis A: General

Volume 156, Issue 1, 14 August 1997, Pages 29-41

https://doi.org/10.1016/S0926-860X(97)00003-3 Get rights and content

Abstract

Ultrafine perovskite-type complex oxides LaFe_1−yA_yO_3−λ (A = Mn, Al, Co) were prepared by sol-gel method using citric acid as complex agent, and characterized by XRD, TPR, TG and XPS techniques. The catalytic activities for methane combustion were tested and compared with that of the large particle oxides having the same composition. It was shown that the catalytic activities of ultrafine LaFe_1−yA_yO_3−λ complex oxides were much higher than that of LaFeO₃ sample due to the increase of high valence B-site cations and lattice oxygen content by the substitution of B-site elements. Much higher catalytic activities were also observed for the ultrafine perovskite-type complex oxides compared to their large particle counterparts.

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Citation Excerpt :
The peak intensity increases when the calcination temperature increases from 800 °C to 1000 °C. Furthermore, the redox catalyst is calcined for 4 h according to previous publication for LaFeO3 preparation (Zhong et al., 1997). Therefore, the obtained powder is then calcined at 900 °C for 4 h in a 15%CO2-N2 atmosphere to form the perovskite structure.
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ArticleMethane combustion over B-site partially substituted perovskite-type LaFeO3 prepared by sol-gel method

Abstract

Appl. Catal.

Appl. Catal. A

J. Catal.

Catal. Today.

Stud. Surf. Sci. Catal.

Ind. Eng. Chem., Prod. Res. Dev.

Bull. Chem. Soc. Jpn.

J. Chem. Soc., Chem. Commun.

Article
Methane combustion over B-site partially substituted perovskite-type LaFeO₃ prepared by sol-gel method