CeO 2 -Promoted Ni/SiO 2 Catalysts for Carbon Dioxide Reforming of Methane: The Effect of Introduction Methodologies

Three typical methods, subsequent coating, co-impregnation and sequential impregnation, were employed to investigate the effect of introduction methodologies for CeO2-promoted Ni/SiO2 catalysts. The CeO2@Ni/SiO2 catalyst prepared with the subsequent coating method was found to exhibit the best initial activity and superior long-term stability in CO2 reforming of methane. Comparative characterizations documented that small Ni size and intimate Ni–CeO2 contact were generated on the CeO2@Ni/SiO2 catalyst, leading to excellent reforming activity. In addition, pronounced redox property and strong surface basicity were created on the CeO2@Ni/SiO2 catalyst, resulting in exceptional coke resistance and thus superior long-term stability. This work unravels the impact of various introduction methods on the catalyst structure, which would help design robust nanocomposite catalysts with outstanding catalytic performance.