Electrocatalytic nitrogen reduction to ammonia by atomically precise Cu 6 nanoclusters supported on graphene oxide.

The electrocatalytic nitrogen reduction reaction (NRR) enables the production of ammonia by the use of renewable energy, providing a direct method for nitrogen fixation. Nevertheless, the NRR process under ambient conditions is often impeded by inertness of N 2 and the occurrence of hydrogen evolution as a byproduct in aqueous electrolytes, resulting in a diminished reaction rate and reduced efficiency. In this study, we synthesized Cu 6 (SMPP) 6 nanoclusters (Cu 6 NCs for short) and immobilized them on graphene oxide (GO) to investigate their electrocatalytic nitrogen reduction reaction (ENRR) using an H-cell setup. The GO-supported Cu 6 NCs exhibit enhanced catalysis with a high NH 3 yield rate of 4.8 μg h -1 cm -2 and a high faradaic efficiency up to 30.39% at -1.1 V. Quantum chemistry calculations reveal that the Cu 6 S 6 cluster on GO support facilitates the N 2 adsorption and NN bond activation with a surmountable energy barrier for the potential-determining step (N 2 * → NNH*).