Beyond Single‐Atom Catalysis: Engineering Synergistic Atomic Sites for Selective CO ₂ Electroreduction

The electrochemical CO ₂ reduction reaction (CO ₂ RR) powered by intermittent renewable electricity represents a cornerstone technology for achieving global carbon neutrality, enabling the conversion of anthropogenic CO ₂ emissions into value‐added chemicals and fuels while closing the anthropogenic carbon cycle. Downsizing metal catalysts from bulk materials and nanoparticles to isolated single atoms or precisely defined few‐atom clusters supported on functional substrates maximizes atomic utilization efficiency, creates highly unsaturated coordination environments, and induces unique electronic localization effects. These structural features endow atomic‐scale catalysts with unprecedented catalytic properties that cannot be achieved by their conventional counterparts. This review provides a critical and timely overview of the most significant recent advances in single‐atom catalysts (SACs), dual‐atom catalysts (DACs), and multiatom cluster catalysts for CO ₂ RR. We first elucidate the fundamental principles governing the catalytic performance of SACs, with a particular emphasis on advanced coordination environment engineering strategies including vacancy creation, heteroatom doping, and asymmetric ligand design. Subsequently, we highlight the unique synergistic effects of DACs and cluster catalysts that overcome the intrinsic limitations of single‐site catalysis, especially for the kinetically challenging CC coupling reactions leading to high‐value C ₂₊ products. Finally, we identify the critical remaining challenges and propose promising future research directions to accelerate the practical implementation of atomic‐scale catalysts for industrial CO ₂ electrolysis.