Fabrication of La_1-xCa_xFeO₃ perovskite-type oxides with macro-mesoporous structure via a dual-template method for highly efficient soot combustion

Minjie Zhao，Jixing Liu，Jian Liu，Junfeng Xu，Zhen Zhao，Yuechang Wei，Weiyu Song

State Key Laboratory of Heavy Oil Processing,China University of Petroleum

摘 要：A series of three-dimensionally ordered macro-mesoporous（3DOMM） La_1-xCa_xFeO₃（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 3 DOMM La_1-xCa_xFeO₃ exhibits abundant wormlike mesoporous channels about 3 nm in diameter on macroporous skeleton walls.The excellent catalytic activity of soot combustion benefits from not only 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 La_0.8Ca_0.2FeO₃ exhibits superior catalytic performance for soot combustion,which shows T₅₀ of396℃.It is 189℃lower than that without catalyst.A combination of structure and composition in the design of catalyst can be widely extended to other catalytic systems.

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