Porous nitrogen–doped carbon derived from biomass for electrocatalytic reduction of CO2 to CO

Abstract

Electrochemical reduction of CO2 using electricity from renewable sources is emerging as a promising approach for reducing global CO2 emissions and converting CO2 into useful chemicals. Here, a nitrogen–doped porous carbon material is proposed to electrocatalytically reduce CO2 to CO with high activity, selectivity and superior durability. The material is synthesized by a facile one–step pyrolysis approach using biomass, namely wheat flour, and KOH as starting materials. The resulting materials show high surface area with hierarchical porous structures, and the nitrogen content and functional species can be controlled to some extent via the pyrolysis temperature. The catalyst exhibits a maximum faradaic efficiency of 83.7% and a partial current density of CO of 6.6mAcm−2 at an overpotential of 0.71V in aqueous bicarbonate medium. Moreover, it also demonstrates superior long–term durability with trivial loss of activity and selectivity. Mechanistic study indicates that the pyridinic nitrogen is responsible for the high catalytic activity.