Industrial‐Level CO₂ Electroreduction Using Solid‐Electrolyte Devices Enabled by High‐Loading Nickel Atomic Site Catalysts

Abstract Transition‐metal atomic site catalysts (ASCs) are a new class of catalytic system for CO₂ electroreduction, however, their practical application is greatly hindered by the challenge that it's still difficult for them to simultaneously achieve industrial‐level current density and high selectivity. Herein a new strategy is reported for hundreds of gram‐scale and low‐cost production of Ni‐ASCs on 3D porous nanocarbon with high‐loading NiN₃ sites for greatly boosting the electroreduction of CO₂ to CO with both industrial‐level current density and high selectivity. It is discovered that although Ni‐ASCs with high‐loading (Ni‐ASCs/4.3 wt.%) and low‐loading (Ni‐ASCs/0.8 wt.%) both show above 95% Faradic efficiency for CO (FE_CO) under a wide potential range in H‐cell, in flow cell, Ni‐ASCs/0.8 wt.% can only achieve FE_CO of 43.6% at a current density of 343.9 mA cm⁻², significantly lower than those (95.1%, 533.3 mA cm⁻²) of Ni‐ASCs/4.3 wt.% under same potential, first revealing the important role of high‐loadings of single atom sites in promoting the high‐selectivity electrolysis at industrial‐level current density. Most importantly, it is demonstrated that Ni‐ASCs/4.3 wt.%‐based membrane electrode assembly (MEA) exhibits outstanding durability at industrial‐level current density of 360.0 mA cm⁻², which is one of the best performances for the realistic electroreduction of CO₂ to CO in the reported ASCs‐based MEA systems.