Gas-Phase Synthesis of Ni-CeOx Hybrid Nanoparticles and Their Synergistic Catalysis for Simultaneous Reforming of Methane and Carbon Dioxide to Syngas

摘要

We develop a new Ni-CeOx hybrid nano particle as a high-performance catalyst for dry reforming of methane with carbon dioxide (DRM) using a facile gas-phase synthetic approach. The crystallites of Ni and CeO2 were homogeneously self-assembled as a hybrid nanostructure, creating a large amount of Ni-Ce-O interface for a strong metal-support interfacial interaction. Chemical composition and oxidation state of the hybrid nanostructure were tunable directly in the aerosol state. The results show that the starting temperature of catalysis by Ni-based catalysts reduced by similar to 150 degrees C through the hybridization with CeO2 followed by a direct H-2 reduction in the aerosol state. In comparison to Ni-only nanoparticle, the Ni-CeOx hybrid nanoparticle showed stable and high conversion for CH4 and CO2 with a remarkably turnover frequency at low temperature (0.1 s(-1) at 450 degrees C). The amount of coke formation greatly reduced by 18X, whereas the H-2/CO ratio was constant at similar to 0.8 by a 1.5x of the increase of CO2/CH4 ratio. The work demonstrated a facile route for controlled synthesis of Ni-CeOx hybrid nanoparticles with a very high catalytic activity and stability of DRM. The findings of this study can shed light on the mechanism of Ni-Ce-O synergistic catalysis, which can be especially useful for methane-based energy applications.