Reducing carbon deposition and enhancing reaction stability by ceria for methane dry reforming over Ni@SiO2@CeO2 catalyst

Abstract

Low temperature methane dry reforming by Ni-based catalysts is an economic way to convert greenhouse gases of CH4 and CO2, but carbon deposition is a great challenge. Taking the advantage of mobile oxygen on CeO2, we synthesized a Ni@SiO2@CeO2 catalyst by coating ceria on surface of Ni@SiO2 to reduce carbon deposition. H2 temperature-programmed reduction, X-ray photoelectron spectra and oxygen temperature-programmed desorption demonstrated the high oxygen mobility from ceria in Ni@SiO2@CeO2 catalyst, which significantly reduced carbon deposition and enhanced stability of methane dry reforming reaction. Experimental results revealed that methane dry reforming performance was one and a half times higher, but carbon deposition was one half lower, over the Ni@SiO2@CeO2 catalyst than over the Ni@SiO2 catalyst. The strategy of ceria coating in reducing carbon deposition and enhancing reaction stability could also be applied to other heterogeneous reactions suffering carbon deposition.