Advances and perspectives on heteronuclear dual-atomic catalysts for prevailing the linear scaling relationship in electrocatalytic CO reduction

Inspired by nature's construction of the heteronuclear dual-atomic sites, Fe-Mo co-factor, for nitrogen fixation and the carbon cycle, researchers have focused extensively on developing heteronuclear dual-atomic site catalysts (HN-DACs) for electrochemical CO reduction reactions (CORR). The HN-DACs, having different metal sites at a distance limit for the electronic interaction, can be promising models, offering one site for C-affinity and another site for O-affinity, thereby facilitating the breaking of the linear scaling relationship for CORR. Moreover, HN-DACs have excellent stability and selectivity due to the synergistic influence between heteronuclear dual-atomic sites, which affects the electronic structure and charge distribution over the whole DAC's surface. This review highlights the merits of DACs, in particular HN-DACs, and how they can break the linear scaling relationship towards CORR. The logical optimization strategies for HN-DACs and their synthesis, characterization, and stability are also discussed. Further, the recent advances in HN-DACs towards electrocatalytic CORR are extensively documented. Finally, challenges and future prospects with HN-DACs are also highlighted.