Highly efficient N2 electroreduction to NH3 on Cu7·2S4/C with sulfur vacancies synthesized using a continuous microchannel reactor.

The electrochemical nitrogen reduction reaction (NRR) has emerged as a sustainable and environmental–friendly alternative for ammonia synthesis compared with conventional Haber–Bosch process. However, considerable challenges persist in developing cost-effective catalysts for NRR. Herein, Cu 7 · 2 S 4 /C was synthesized using a continuous microchannel reactor followed by carbonization sulfurization at 600 °C. The as-prepared Cu 7 · 2 S 4 /C catalyst, featuring abundant sulfur vacancies, exhibited outstanding electrochemical performance for NRR, achieving an ammonia yield of 52 μg h − 1 mg cat. − 1 and Faraday efficiency of 32.2%. In addition, density functional theory calculations suggest that sulfur vacancies contribute to a decrease in Gibbs free energy during N 2 -activated hydrogenation, thereby facilitating adsorption of N 2 and formation of Cu–N bonds at catalytic active centers. This study introduces a novel strategy for synthesizing economical and efficient NRR electrocatalysts based on transition metal-based metal–organic frameworks. [Display omitted] • Cu-BTC was successfully synthesized using a continuous microchannel reactor. • BTC-derived Cu 7 · 2 S 4 /C with sulfur vacancy exhibited enhanced nitrogen reduction reaction performance for ammonia synthesis. • Cu 7.2 S 4 /C facilitated N 2 chemisorption and reduced Gibbs free energy for N 2 -activated hydrogenation. [ABSTRACT FROM AUTHOR]