Highly Boosted Reaction Kinetics in Carbon Dioxide Electroreduction by Surface‐Introduced Electronegative Dopants

Abstract

Abstract Effectively improving the selectivity while reducing the overpotential over the electroreduction of CO 2 (CO 2 ER) has been challenging. Herein, electronegative N atoms and coordinatively unsaturated NiN 3 moieties co‐anchored carbon nanofiber (NiN 3 NCNFs) catalyst via an integrated electrospinning and carbonization strategy are reported. The catalyst exhibits a maximum CO Faradaic efficiency (F.E.) of 96.6%, an onset potential of −0.3 V, and a low Tafel slope of 71 mV dec −1 along with high stability over 100 h. Aberration corrected scanning transmission electron microscopy, X‐ray absorption spectroscopy, and X‐ray photoelectron spectroscopy identify the atomically dispersed NiN 3 sites with Ni atom bonded by three pyridinic N atoms. The existence of abundant electronegative N dopants adjoin the NiN 3 centers in NiN 3 NCNFs. Theoretical calculations reveal that both, the undercoordinated NiN 3 centers and their first neighboring C atoms modified by extra N dopants, display the positive effect on boosting CO 2 adsorption and water dissociation processes, thus accelerating the CO 2 ER kinetics process. Furthermore, a designed ZnCO 2 battery with the cathode of NiN 3 NCNFs delivers a maximum power density of 1.05 mW cm −2 and CO F.E. of 96% during the discharge process, thus providing a promising approach to electric energy output and chemical conversion.

Topics & Concepts