Electrochemical reduction of N2 in mild conditions using redox or chemical catalysis: towards alternatives to the Haber-Bosch process?

Decarbonized Ammonia (NH 3 ) production from N 2 reduction under mild conditions (temperature and pressure) is highly desirable. The overall process requires a six electrons-six protons addition to N 2 . Activation of the very inert dinitrogen molecule (N 2 ) is nevertheless challenging. In this review, we present works focusing on two alternative strategies for N 2 fixation using electrochemical means. The first one relies on activation of N 2 at Li/Ca, followed by proton transfers to form NH 3 , while the second relies on the use of transition metal complexes to achieve proton-coupled electron transfers. • Electrochemical reduction of N 2 . • Lithium N 2 reduction. • Homogeneous electrocatalysis. • Electrochemical N 2 splitting. • Mechanism of N 2 functionalization.