A Bi-Co Corridor Construction Effectively Improving The Selectivity of Electrocatalytic Nitrate Reduction Towards Ammonia by Nearly 100.

Improving the selective ammonia production capacity of electrocatalytic nitrate reduction reaction (NO 3 RR) at ambient conditions is critical to the future development and industrial application of electrosynthesis of ammonia. However, the reaction involves multi-proton and electron transfer as well as the desorption and underutilization of intermediates, posing a challenge to the selectivity of NO 3 RR. Here we modulated the electrodeposition site of Co by depositing Bi at the bottom of the catalyst, thus obtaining the Co+Bi@Cu NW catalyst with a Bi-Co corridor structure. In 50 mM NO 3 - , Co+Bi@Cu NW exhibits a highest Faraday efficiency of ∼100% (99.51%), an ammonia yield rate of 1858.2 μg·h -1 ·cm -2 and high repeatability at -0.6 V versus the reversible hydrogen electrode. Moreover, the change of NO 2 - concentration on the catalyst surface observed by in situ reflection absorption imaging and the intermediates of the NO 3 RR process detected by electrochemical in situ Raman spectroscopy together verified the NO 2 - trapping effect of the Bi-Co corridor structure. We believe that the measure of modulating the deposition site of Co by loading Bi element is an easy-to-implement general method for improving the selectivity of NH 3 production as well as the corresponding scientific research and applications. This article is protected by copyright. All rights reserved.