Fabrication of La1−Ca FeO3 perovskite-type oxides with macro-mesoporous structure via a dual-template method for highly efficient soot combustion

Abstract A series of three-dimensionally ordered macro-mesoporous (3DOMM) La1−xCaxFeO3 (x=0−0.3) perovskite-type oxides were designed and successfully fabricated for the first time via a dual-template method. In which, PMMA and Brij-56 were employed as the hard template and soft template, respectively. It is found that 3DOMM La1−xCaxFeO3 exhibit abundant wormlike mesoporous channels about 3 nm in diameter on macroporous skeleton walls. The excellent catalytic activity of soot combustion is not only benefited from the well-designed hierarchical porous structure of catalyst, but also the redox electron pair of Fe3+/Fe4+ induced by the doping of low-valent alkaline earth metal Ca to A-site of LaFeO3. 3DOMM La0.8Ca0.2FeO3 exhibits superior catalytic performance for soot combustion, which shows T50 of 396 oC. It is 189 oC lower than that without catalyst. A combination of structure and composition in the design of catalyst can be widely extended to other catalytic systems.