High surface density of Mn-N sites in atomically dispersed Mn catalyst for effective CO2 electroreduction

An atomically dispersed Mn catalyst is prepared by combining carbon protection and pyrolysis strategies, which exhibits a maximum of 90% CO faradaic efficiency and a low overpotential of 80 mV to produce CO due to the high surface density of Mn-N4 sites, abundant defects, and high electrochemical active surface area. [Display omitted] •Atomically dispersed Mn catalyst is synthesized via carbon protection and pyrolysis strategies.•The Mn-N-C catalyst possesses a high surface density of Mn-N4 sites.•The Mn-N-C catalyst shows 90 % CO faradaic efficiency and a low overpotential of 80 mV to produce CO.•The introduction of Mn single atoms leads to abundant surface defects. Electrocatalytic CO2 reduction to chemical fuels driven by renewable energy provides a highly promising route to fabricate the circular economy. However, the high overpotential and competitive side reactions severely hinder the industrial application of this process. Here we prepare the atomically dispersed Mn catalyst with high surface density of Mn-N sites via carbon protection and pyrolysis strategies, which exhibits a maximum of 90 % CO faradaic efficiency and the low overpotential of 80 mV to produce CO. The enhanced catalytic performance is mainly attributed to the high surface density of Mn-N4 sites, abundant defects, and high electrochemical active surface area. This work provides the possibility to improve the CO2 electroreduction performance of inert catalysts through surface structure design.