CuCo2S4 integrated multiwalled carbon nanotube as high-performance electrocatalyst for electroreduction of nitrogen to ammonia.

Ammonia synthesis based on electrocatalytic nitrogen reduction reaction (NRR) by using renewable sources of energy under ambient conditions has attracted wide research attentions. Herein, we report that the noble-metal-free CuCo 2 S 4 /multiwalled carbon nanotube nanocomposite, which is synthesized via a facile one-step hydrothermal and sulfuration approach, can work as the high active and durable catalyst for electrocatalytic NRR. This nanocomposite achieves a high NH 3 yield of 137.5 μg h−1 mg cat −1 and a high Faradaic efficiency of 8.7% at −0.5 V vs reversible hydrogen electrode (RHE) in 0.1 M Na 2 SO 4 solution, which outperforms CuCo 2 S 4 counterpart and most reported NRR catalysts. These results reveal that the MWCNT in nanocomposite not only suppresses the aggregation of CuCo 2 S 4 nanoparticles and maximizes the exposure of active sites, but also contributes to the synergistic effect between CuCo 2 S 4 nanoparticles and MWCNT, and facilitates the interfacial reaction kinetics. CuCo 2 S 4 /multiwalled carbon nanotube nanocomposite has been facilely prepared and experimentally proven to act as the high-active and stable catalyst for electrochemical N 2 reduction to NH 3 with high selectivity in neutral aqueous solution. Image 1 • CuCo 2 S 4 /MWCNT is synthesized via a facile one-step approach. • CuCo 2 S 4 /MWCNT works as a high active and durable catalyst for NRR. • The synergistic effect can facilitate the interfacial reaction kinetics. [ABSTRACT FROM AUTHOR]