Hierarchical Ni/N/C Single‐Site Catalyst Achieving Industrial‐Level Current Density and Ultra‐Wide Potential Plateau of High CO Faradic Efficiency for CO₂ Electroreduction

Abstract The practical applications of CO₂ electroreduction to CO driven by renewable electricity should simultaneously meet the requests of industrial‐level CO partial current density (J_CO) at least 100 mA cm⁻², wide potential window of high CO faradic efficiency (FE_CO), and low cost. Herein, a new strategy is reported to construct porous hierarchical Ni/N/C single‐site catalyst with excellent catalytic activity via coating Ni‐containing ZIF‐8 on mesostructured basic magnesium carbonate template followed by pyrolysis. The abundant micropores facilitate the formation of numerous edge‐hosted Ni‐N₄ sites with high intrinsic activity, and the interconnected macro/mesopores much promote CO₂ delivery and CO release for the full expression of intrinsic activity. Consequently, the catalyst exhibits the industrial‐level J_CO of 105–462 mA cm⁻² at the potential range of −0.6∼−1.3 V with ultra‐wide high FE_CO plateau (>90%@−0.4∼−1.3 V), showing great promise for practical application. This study provides a general synthetic strategy to explore high‐performance hierarchical M/N/C electrocatalysts.