LAUSR

Covalent organic frameworks (COFs) have been applied as potential electrocatalysts for CO2 reduction reaction (CO2RR) due to their adjustable architecture and porous feature. Herein, tetraanhydrides of 2,3,9,10,16,17,23,24‐octacarboxyphthalocyanine cobalt(II) (CoTAPc) are used as nodes to couple with 5,15‐di(4‐aminophenyl)‐10,20‐diphenylporphyrin (DAPor) or 5,15,10,20‐tetrayl(4‐aminophenyl)porphyrin (TAPor) via imidization reaction to fabricate novel coupled phthalocyanine–porphyrin Type 1:2 (CoPc‐2H2Por) or Type 1:1 (CoPc‐H2Por) COFs. Electrocatalytic CO2RR experiments show that both Type 1:2 and Type 1:1 COFs exhibit the maximum Faraday efficiency over 90% with high stability, while the Type 1:2 COF (CoPc‐2H2Por) delivers lower overpotential, higher current density, and CO selectivity than Type 1:1 COF (CoPc‐H2Por) and CoPc monomer. Theoretical and experimental results reveal that the better CO2RR activity of CoPc‐2H2Por than CoPc‐H2Por can be attributed to its larger pore size and conjugate structure, which then cause more efficient electron transfer, adsorption/activation of CO2, faster mass transfer, and reaction kinetics. This work provides a new idea in the structural design of COF‐based electrocatalyst for efficient CO2RR.