Facile synthesis of highly dispersed Ir/LaFeO3 catalysts for propene total oxidation

Abstract

A series of Ir/LaFeO3 catalysts calcined at 300–600 °C were synthesized by a solvent-free method and tested for propene total oxidation. Various characterizations depicted that iridium was well-dispersed on LaFeO3 with no detectable iridium-related particles or aggregates. The loading of iridium hardly changed the structural and textural properties of LaFeO3, but greatly enhanced the low-temperature reducibility and oxygen mobility, leading to superior propene oxidation activity. For Ir/LaFeO3 series, the catalytic activity decreased as the calcination temperature increased, due to the declined reducibility and active oxygen species content. Ir/LaFeO3-300 was demonstrated to be the optimal catalyst with the best propene oxidation performance (T90 = 246 °C), excellent long-term stability, and decent water-resistance. Treating Ir/LaFeO3-300 in a reducing atmosphere further improved its catalytic performance by enhancing low-temperature reducibility and increasing surface-active oxygen species. Overall, this study provides insights into the synthesis of highly efficient and stable iridium-based catalysts for VOCs oxidation.