Single Metal Atoms Anchored on N-Doped Holey Graphene as Efficient Dual-Active-Component Catalysts for Nitroarene Reduction

Developing efficient catalysts for facilitating organic synthesis processes is a popular but challenging topic in modern chemical industries. A combination of active metals and an active support structure is, in theory, an effective strategy for boosting catalytic activity but such combinations have been rarely explored. Herein, a strategy for fabricating highly efficient dual-active-component catalysts (DACCs) is presented by anchoring single-atom metals (M_1; e.g., Pd₁, Ni₁, Co₁, and Zn₁) or double-atomic metals (e.g., Pd₁-Co₁, Pd₁-Ru₁, and Pd₁-Ni₁) on nitrogen-doped holey graphene (NHG). Among the resultant DACCs, Pd₁/NHG, which combines atomically dispersed metal species and an active NHG carbocatalyst, has been shown to display enhanced catalytic performance toward nitroarene reduction . In particular, its catalytic efficiency in reducing 4-nitrophenol corresponds to a turnover frequency of 2.0 min⁻¹, which is 97 times higher than the benchmark set by commercial Pd/C catalysts (5.0 wt.%), and vastly superior to those of its counterparts (e.g., NHG carbocatalyst and NHG supported Pd clusters. Notably, four intermediates and two active components (i.e., NHG and single-atom Pd) in the nitroarene reduction process have been identified. This study presents an effective and versatile synthetic strategy to prepare DACCs through the combination of metallic catalysts and a carbocatalyst substrate.