Ni and nitrogen-codoped ultrathin carbon nanosheets with strong bonding sites for efficient CO₂ electrochemical...

Single-atom catalysts have attracted wide attention recently because of their unique size quantum effect and superior atom utilization in CO₂ reduction reaction (CO₂RR). Here, ultrathin Ni and nitrogen-codoped carbon nanosheets (Ni-N-CNSs) were proposed by a facile in-situ pyrolytic strategy. The ultrathin porous structure of Ni-N-CNSs affords large surface area, rich mesoporous volume and vast uniformly dispersed Ni atoms. The optimized catalyst exhibits a high CO Faradaic efficiency of nearly 100%, partial current density of 121.4 mA mg^-1, CO production rate of 37.7 μmol mg^-1 min^-1, and super durability. In addition, the first principles calculations and the Mulliken charge analyses reveal the Ni sites show high bonding force towards the CO₂ molecules, which gives rise to the high activity and selectivity of Ni-N-CNSs in CO₂RR.