Fig. 5: Reaction mechanisms at about -1.5 V vs SHE.

a Kinetic barriers of *NO reduction toward ammonia (NH3) formation at ~ -1.5 V vs SHE on the Cu(100) surface. b Probability of distribution of hydrogen height along direction normal to the Cu(100) surface. Snapshots of the interface at about c −0.75 V and d −1.5 V vs SHE (intermediates are removed for clarity). e Schematic diagrams for two different routes of C-N coupling: surface-mediated coupling of *NH with *CO or *NH direct coupling with CO(aq).