Ni redispersion from SiO₂ to molybdenum carbide creates dual interfaces to boost tandem CO₂ hydrogenation

Interface engineering is crucial in the design of supported metal catalysts, as it significantly influences the catalytic process, particularly in terms of selectivity. Herein, we discover the redispersion of Ni nanoparticles from SiO₂ to molybdenum carbide (Mo₂C) being induced by the strong interaction between metal and Mo₂C. Parameters affect such migration are thoroughly investigated from carbon source, proximity between Ni and Mo₂C to activation atmosphere and temperature. The established dual interface on Mo₂C-Ni/SiO₂ catalyst exhibits excellent catalytic performance for CO₂ hydrogenation, readily shifting the selectivity from 91% CO on Ni/Mo₂C to near 100% CH₄ on Mo₂C-Ni/SiO₂. Density functional theory calculations further verify the interfacial synergy between Ni/Mo₂C and Ni/SiO₂ sites with low barrier for CO₂ activation and a subsequent successive hydrogenation of CO. These findings highlight the important role of strong metal-support interaction (SMSI) induced metal redispersion for the rational fabrication of dual interfaces, leading to a highly active catalyst for target products.