Molecular Electrochemical Reductive Splitting of Dinitrogen with a Molybdenum Complex**
Résumé
Abstract Nitrogen reduction under mild conditions (room T and atmospheric P ), using a non‐fossil source of hydrogen remains a challenge. Molecular metal complexes, notably Mo based, have recently been shown to be active for such nitrogen fixation. We report electrochemical N 2 splitting with a Mo III triphosphino complex [(PPP)MoI 3 ], at room temperature and a moderately negative potential. A Mo IV nitride species was generated, which is confirmed by electrochemistry and NMR studies. The reaction goes through two successive one electron reductions of the starting Mo species, coordination of a N 2 molecule, and further splitting to a Mo IV nitride complex. Preliminary DFT studies support the formation of a bridging Mo I N 2 Mo I dinitrogen dimer evolving to the Mo nitride via a low energy transition state. This example joins a short list of molecular complexes for N 2 electrochemical reductive cleavage. It opens a door to electrochemical proton‐coupled electron transfer (PCET) conversion studies of N 2 to NH 3 .