Engineering Abundant Edge Sites of Bismuth Nanosheets toward Superior Ambient Electrocatalytic Nitrogen Reduction via Topotactic Transformation

Abstract

Production of efficient and cost-effective metal-based catalysts for electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions is quite challenging. In this work, metal bismuth (Bi) nanosheets with a single-crystalline structure supported on a carbon fiber paper were prepared through the in situ electrocatalytic topotactic transformation of bismuth iodide oxide nanosheets. These Bi nanosheets can be used as efficient non-noble metal catalysts for NRR, achieving an NH3 yield of 12.49 μg h–1 mgcat.–1 and a high faradaic efficiency of 7.09%. Density functional theory calculations reveal that although the basal plane of Bi nanosheets is relatively inert, the exposed edge sites are conductive to the adsorption and activation of N2 molecules. This work presents the significance of using the topotactic transformation strategy for NRR and provides an inspiration for the development of efficient metal-based catalysts.