Abstract: | Confined catalysis in a 2D system is of particular interest owing to the facet control of the catalysts and the anisotropic kinetics of reactants, which suppress side reactions and improve selectivity. Here, a 2D‐confined system consisting of intercalated Pt nanosheets within few‐layered graphene is demonstrated. The strong metal–substrate interaction between the Pt nanosheets and the graphene leads to the quasi‐2D growth of Pt with a unique (100)/(111)/(100) faceted structure, thus providing excellent catalytic activity and selectivity toward one‐carbon (C1) products for the glycerol oxidation reaction. A hierarchically porous graphene architecture, grown on carbon cloth, is used to fabricate the confined catalyst bed in order to enhance the mass‐diffusion limitation in interface‐confined reactions. Owing to its unique 3D porous structure, this graphene‐confined Pt catalyst exhibits an extraordinary mass activity of 2910 mA mgPt ?1 together with a formate selectivity of 79% at 60 °C. This paves the way toward rational designs of heterogeneous catalysts for energy‐related applications. |