Interfacing with silica boosts the catalysis of copper

Metal-support interaction is one of the most important parameters in controlling the catalysis of supported metal catalysts. Silica, a widely used oxide support, has been rarely reported as an effective support to create active metal-support interfaces for promoting catalysis. In this work, by coating Cu microparticles with mesoporous SiO₂, we discover that Cu/SiO₂ interface creates an exceptional effect to promote catalytic hydrogenation of esters. Both computational and experimental studies reveal that Cu-H^δ- and SiO-H^δ+ species would be formed at the Cu-O-SiO_x interface upon H₂ dissociation, thus promoting the ester hydrogenation by stablizing the transition states. Based on the proposed catalytic mechanism, encapsulting copper phyllosilicate nanotubes with mesoporous silica followed by hydrogen reduction is developed as an effective method to create a practical Cu nanocatalyst with abundant Cu-O-SiO_x interfaces. The catalyst exhibits the best performance in the hydrogenation of dimethyl oxalate to ethylene glycol among all reported Cu catalysts.