Multi-Atom Sub-Nanometer Assemblies on Interpenetrating Multi-Chambered N/C Nanospheres

The atomically dispersed catalysts have received much attention due to maximum atom utilization and enhanced catalytic performance. Compared with the widely studied single-atom catalysts and dual-atom catalysts, the multi-atom catalysts (MACs) have unique features of collective effect of multiple metal atoms and more designable and tunable coordination environments that are desirable for catalytic reactions. Up to now, the research on MACs remains quite scarce, mainly restricted by the synthetic difficulty in precisely controlling the composition and arrangement of multiple metal atoms in MACs. Herein, we report a versatile soft-hard dual template route for the synthesis of both mononuclear MACs and heteronuclear MACs, which are stabilized on interpenetrating multi-chambered N/C nanospheres. The as-synthesized Ni/Cu-MAC exhibits high performance for electrocatalytic CO₂ reduction reaction, delivering a CO Faraday efficiency of >99% at low required potentials (-0.26 V to -0.56 V). A cathode energy efficiency >75% is achieved at an industrial current density of 0.60 A cm^-2, representing highly competitive performance among the reported CO₂-to-CO electrocatalysts. The experimental and computational results demonstrate the synergistic effect between the atomically dispersed Ni and Cu for promoting the catalytic conversion of CO₂ to CO.