SrFe1−xSnxO3−δ nanoparticles with enhanced redox properties for catalytic combustion of benzene

Abstract

A series of Sn-substituted strontium ferrates SrFe_1−xSn_xO_3−δ (x = 0, 0.25, 0.50, 0.75 and 1.0) were prepared by the polymerized complex method. The influence of the substitution of Fe in SrFeO_3−δ with Sn on structural, redox, and catalytic properties was investigated. X-ray diffraction and ⁵⁷Fe Mössbauer analyses revealed that the partial substitution of Fe with Sn expanded the lattice of the perovskite-type structure, leading to elongation of Fe–O bonds. The partial substitution resulted in the decline of the particle size and the increase of the specific surface area. H₂-TPR and TG measurements in a H₂ or O₂ flow indicated that the partial substitution significantly accelerated the redox rates of Fe at 500 °C. Due to the increased surface area and enhanced redox properties, the partially substituted SrFe_1−xSn_xO_3−δ showed higher catalytic activity than SrFeO_3−δ for the combustion of benzene.