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. Engineering catalyst interfaces plays a key role in designing supported metal systems. Here, the authors report that Ni nanoparticles redisperse from SiO₂ to molybdenum carbide, forming dual interfaces that enhance tandem CO₂ hydrogenation.