Dependency of CO2 methanation on the strong metal-support interaction for supported Ni/CeO2 catalysts

The strong metal-support interaction (SMSI) for supported Ni/CeO2 catalysts with different CeO2 nanomorphologies was systematically explored. The degree of encapsulation of Ni particles originating from the SMSI effect was found to follow the trend of Ni/CeO2-(1 1 1) > Ni/CeO2-(1 0 0) > Ni/CeO2- (110 + 100), which parallels the CO2 hydrogenation activity. Quasi in situ XPS reveals the presence of Ce3+ sites in accordance with the formation of an amorphous surface CeOx layer encapsulating the Ni nanoparticles. In situ DRIFTS indicates the reaction pathway and rate-determining step are dependent on the degree of the SMSI effect, leading to distinct selectivities towards CH4, especially at a high weight hourly space velocity (WHSV). These findings present a fundamental strategy about tailoring catalytic performance through support facet dependent susceptibility of SMSI phenomena. (C) 2022 Published by Elsevier Inc.