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

• A doping-segregation method is developed to enhance the Ni-SiO 2 interaction. • This strategy makes inert silica to be active SiO 2 with chemical functionality. • The enhanced Ni-SiO 2 interaction greatly improves the catalytic stability for DRM. • The interfacial Si-O-Ni sites inhibit the formation of coke and oxidation of Ni. Silica (SiO 2) has been widely used as inert support to better disperse and stabilize active metal nanoparticles. However, enhancing the interaction between the active metal and SiO 2 could make inert silica to be active SiO 2 with chemical functionalities that can be involved in the catalytic process. Here, a Ni doping-segregation SiO 2 with post-annealing strategy was developed to achieve tunable Ni-SiO 2 interaction with abundant interfacial Si-O-Ni sites. The synthesized NiSiO x catalysts with enhanced Ni-SiO 2 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 SiO 2 -based catalysts, changing the traditional perception of inert SiO 2 for the DRM process. The controlled metal-SiO 2 interaction also allows SiO 2 to be used to facilitate the catalytic process in various challenging reactions. [ABSTRACT FROM AUTHOR]