LaFeO3 perovskite-type oxide prepared by oxide-mixing, co-precipitation and complex synthesis methods

摘要

The perovskite oxide, LaFeO3, was synthesized by three different preparation methods i.e., the calcination of a mixture of La2O3 and Fe2O3 (La-Fe-O), a co-precipitated precursor (La-Fe-OH), La(OH)3 and Fe(OH)3, and a heteronuclear complex (La-Fe-CN), La[Fe(CN)6] · 5H2O. The obtained powders were characterized by thermogravimetric analysis, powder X-ray diffraction, electron microprobe analysis, specific surface area measurement and scanning electron microscopy. The formation of LaFeO3 is clearly recognized for La-Fe-O, La-Fe-OH and La-Fe-CN at calcining temperatures above 1000, 800 and 600°C, respectively. The mean particle diameter of La-Fe-CN calcined at 600°C for 2 hours was 30 nm. The LaFeO3 perovskite oxide powder obtained by the thermal decomposition of La-Fe-CN was most uniform on an atomic level and the nanosized LaFeO3 powder was obtained at low temperatures. Furthermore, the sinterability was good.