Powerful CO2 electroreduction performance with N–carbon doped with single Ni atoms

Abstract

The electrocatalytic carbon dioxide reduction reaction (CO₂RR) under ambient conditions provides an intriguing strategy for the conversion of the greenhouse gas CO₂ into valuable chemicals or fuels. However, CO₂RR mainly relies on high-efficiency and low-cost catalysts, and enabling effective CO₂ reduction on N-doped carbon (N–C) catalysts remains a huge challenge. Here, we reported a single dispersed Ni atoms doping strategy to boost the performance of N–C materials for CO₂RR. The N–C nanosheets doped by a Ni single-atom catalyst (Ni–N–C) derived from a novel metal–organic complex precursor exhibited significantly enhanced performances for CO₂ conversion in comparison with a pure N–C sample; furthermore, they presented high CO FE of ∼91.2% and 2.15-fold enhancement in current density at −0.9 V compared to N–C. Density functional theory (DFT) calculations combined with experimental results revealed that the single-atom dispersed Ni could alter the adsorption of intermediates onto the surface of the catalyst, further suppressing HER and boosting the CO₂RR performance. The long-term stability tests demonstrated that the obtained Ni–N–C sample could be used for 22 h without obvious deactivation under ambient conditions. This work provides a guideline for rationally tuning the performance of cost-effective nanostructured N–C catalysts by this atomic scale metal-doping strategy.