One‐Pot Sequential Coordination–Covalent Construction of Symmetry‐Broken MN2O2 Catalytic Sites in Cobalt–Polyimide Polymers for Nitrate Electroreduction

Abstract The metal‐nitrogen chelated species, MN 4 , have shown promise as efficient electrocatalysts for nitrate reduction, yet the symmetric arrangement of N atoms results in suboptimal adsorption affinity toward reaction substrates and intermediates. The current approaches to breaking the symmetry of MN 4 suffer from inaccuracy and inhomogeneity because of the lack of strategies stemming from molecular design aspects. Herein, we report the construction of symmetry‐broken MN 2 O 2 sites in coordination polymers via sequential coordination–covalent control in a one‐pot reaction. The dehydrogenating coordination preferentially occurs prior to the covalent imide‐formation reaction, allowing the two reactions to be completely separated to afford molecularly precise polymer electrocatalysts that feature near‐unity coordination degree and monodispersed atomic MN 2 O 2 species with lowered symmetry, facilitating efficient nitrate reduction. Our study provides a design rationale to integrate diverse coordination and covalent chemistries into coordination polymers for electrocatalysis.