Facile Synthesis of Multi-Ni-Core@Ni Phyllosilicate@CeO2 Shell Hollow Spheres with High Oxygen Vacancy Concentration for Dry Reforming of CH4

A great challenge for cheap and active Ni-based catalysts to be utilized for CO2 (dry) reforming of methane (DRM) reaction is their high-carbon-deposition problem. Herein, we designed multi-Ni-core@Ni phyllosilicate@CeO2 (Ni@NiPhy@CeO2) shell hollow sphere catalysts using a facile precipitation method. Compared with Ni@NiPhy without CeO2 shell, Ni@NiPhy@CeO2 exhibits high carbon resistance for the DRM reaction at both high GHSV value of 1880Lg(-1)cath(-1) at 700 degrees C and a low reaction temperature of 600 degrees C. In addition, they show high and stable CH4 and CO2 conversions of 72.8% and 79.1% respectively at 700 degrees C under normal GHSV value of 36Lg(-1)cath(-1). The good catalytic performance of Ni@NiPhy@CeO2 can be attributed to their high sintering resistance of both Ni and CeO2 which yields a high concentration of oxygen vacancies thereby a high catalytic performance and carbon resistance for DRM reaction. The facile synthesis method in this work can easily be applied to design other core-shell hollow catalysts such as Ni-M (M=Mg, Co, Cu, and Fe) silicate@CeO2 according to specific applications.