Hydrophobic porous cobalt catalysts with decoupled active sites for industrial-level CO₂ electroreduction to syngas

The electrochemical production of syngas (CO/H₂) with a tunable and stable ratio over a wide potential range is critical for coupling with intermittent renewable energy, yet remains challenging due to the intrinsic kinetic mismatch between CO₂ reduction (CO₂RR) and hydrogen evolution (HER). Here, we rationally designed hydrophobic porous cobalt-based electrocatalyst (Hole@CoNC/CoPC) incorporating spatially segregated active sites, where CoNC domains drive HER while molecularly dispersed Co-phthalocyanine (CoPC) centers facilitate CO₂RR. Mechanistic investigations reveal that this innovative design addresses three fundamental challenges: (1) spatial site isolation to mitigate cross-interference between competing HER and CO₂RR processes, (2) pore structure engineering to facilitate CO₂ mass transport and enhance reaction kinetics, and (3) hydrophobic pore structure stabilization of triple-phase boundaries via electrowetting suppression. The optimized catalyst achieves unprecedented potential-adaptive syngas regulation, maintaining stable CO/H₂ ratios of 0.5 and 1.7 for Hole@CoNC/CoPC with 10 % and 20 % CoPC, respectively, across an ultra-wide operating window (−0.4 to −1.2 V_RHE), and simultaneously delivers a record current density of −895 mA cm⁻². This work establishes a paradigm for designing multifunctional electrocatalytic systems through architectural control spanning molecular coordination, nanoscale assembly, and hydrophobic mesoporous networks, which effectively decouples competing reactions and provides generalized strategies to address kinetic mismatches in coupled electrochemical processes.