Large-Scale and Highly Selective CO ₂ Electrocatalytic Reduction on Nickel Single-Atom Catalyst

The scaling up of electrocatalytic CO ₂ reduction for practical applications is still hindered by a few challenges: low selectivity, small current density to maintain a reasonable selectivity, and the cost of the catalytic materials. Here we report a facile synthesis of earth-abundant Ni single-atom catalysts on commercial carbon black, which were further employed in a gas-phase electrocatalytic reactor under ambient conditions. As a result, those single-atomic sites exhibit an extraordinary performance in reducing CO ₂ to CO, yielding a current density above 100 mA cm ⁻² , with nearly 100% selectivity for CO and around 1% toward the hydrogen evolution side reaction. By further scaling up the electrode into a 10 × 10-cm ² modular cell, the overall current in one unit cell can easily ramp up to more than 8 A while maintaining an exclusive CO evolution with a generation rate of 3.34 L hr ⁻¹ per unit cell.