A new strategy for mass production of single-atom catalysts for high performance of CO₂ electrochemical reduction

Single-atom catalysts (SACs) are the smallest entities for catalytic reactions with projected high atomic efficiency, superior activity, and selectivity; however, the poor yield for SACs production seriously limits the industry-relevant application. In this work, a simple but robust method was developed for the mass production of single-atom Ni[sbnd]N[sbnd]C catalysts by using hydrogen-bonded organic frameworks (HOFs) as the precursors, exploiting the efficient and low-cost guar gum. Benefiting from its coordinatively unsaturated Ni-N₃ configuration to afford a high catalytic activity, the as-fabricated SA-Ni/NC-900 catalyst shows excellent selectivity and activity for the electrochemical reduction of CO₂ to CO with Faradaic efficiency (FE) of 95.6 %, achieving a turnover frequency (TOF) of ∼34000 h⁻¹ at −0.8 V (vs. RHE) and highly stable performance for more than 24 h. Mass-producing a highly potent single-atom electrocatalyst paves the way for fulfilling the carbon–neutral goal through the carbon-negative CO₂RR process.