Functionalization of inert silica to construct Si-O-Ni interfacial sites for stable dry reforming of methane

Silica (SiO2) has been widely used as inert support to better disperse and stabilize active metal nanoparticles. However, enhancing the interaction between the active metal and SiO2 could make inert silica to be active SiO2 with chemical functionalities that can be involved in the catalytic process. Here, a Ni doping-segregation SiO2 with post-annealing strategy was developed to achieve tunable Ni-SiO2 interaction with abundant interfacial SiO-Ni sites. The synthesized NiSiOx catalysts with enhanced Ni-SiO2 interaction facilitate the formation of interfacial Si-O-Ni sites, which could inhibit the oxidation of Ni species and promote the removal of surface carbon species, leading to superior catalytic stability for dry reforming of methane (DRM). This work provides insights into the interfacial effect of SiO2-based catalysts, changing the traditional perception of inert SiO2 for the DRM process. The controlled metal-SiO2 interaction also allows SiO2 to be used to facilitate the catalytic process in various challenging reactions.