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

Ultrafine perovskite-type complex oxides LaFe1−yAyO3−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 LaFe1−yAyO3−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.