Encapsulation of Iron Nitride by Fe-N-C Shell Enabling Highly Efficient Electroreduction of CO2 to CO

The conversion of CO2 into valuable chemicals has captured extensive attention for its significance in energy storage and greenhouse gas alleviation, but the development of cost-effective electrocatalysts with high activity and selectivity remains the bottleneck. Herein, we designed a Fe-N-C nanofiber catalyst featuring a core-shell structure consisting of iron nitride nanoparticles encapsulated within Fe and N codoped carbon layers that can efficiently catalyze CO2 to CO with nearly 100% selectivity, high faradic efficiency (similar to 95%), and remarkable durability at -0.53 V versus reversible hydrogen electrode. Theoretical calculations reveal that the introduction of an iron nitride core can facilitate the CO intermediate desorption from the Fe and N codoped shell, thus enhancing the catalytic performance of CO2 reduction. This work presents an ideal approach to rationally design and develop transition-metal and N codoped carbon materials for efficient CO2 reduction.