High Loading and Morphology Transformation in Boron Dispersed Copper Electrocatalyst Enables Efficient Nitrate to Ammonia Conversion

ABSTRACT Electrochemical nitrate reduction to ammonia provides a promising route to alleviate nitrate pollution into value‐added chemicals. However, ammonia production is currently suffered low production yield due to inefficient catalyst and less loading (usually less than 11 mg cm −2 ). Here, we fabricated a novel and high‐performance boron nanosheet dispersed copper nanorod (BS‐CuNR) electrocatalyst that displayed remarkable performance at record loading (35 mg cm −2 ). The novel structure of BS‐CuNR produced abundant active sites, and enhances the catalyst‐electrolyte interaction that facilitates the transfer of ions and electrons at high loading. That delivered an industrial‐relevant ammonia production current density (−450 mA cm −2 ) and 91.9% Faraday efficiency with 43.5 mg h −1 cm −2 ammonia production rate at −0.4 V vs. RHE. In‐situ infrared spectroscopy and density functional theory demonstrated that the higher catalytic activity of BS‐CuNR originates from the intrinsic and synergistic catalytic cooperation of B and Cu. Boron incorporation modulates copper's electronic structure to enhance its catalytic activity. The high loading with high production helps to meet the requirements of practical applications.