Electrochemical N2 reduction at ambient condition – Overcoming the selectivity issue via control of reactants’ availabilities

Ammonia production via the electrochemical N2 reduction reaction (NRR) at ambient conditions is highly desired as an alternative to Haber-Bosch process, but remains a great challenge due low efficiency and selectivity caused by competing hydrogen evolution (HER). Herein we investigate effect of availabilities reactants (protons, electrons N2) on NRR using FeOx-coated carbon fiber paper cathode in various configurations. found viable only under proton- high availabilities, which are achieved 0.12 vol% water LiClO4-ethyl acetate electrolyte gaseous supplied membrane-electrode assembly cathode. This results rate 29 ± 19 pmolNH3 s?1 cm?2 Faradaic 70 24% applied potential ?0.1 V vs. NHE. Other (high proton-, or N2-availability, both) yield lower negligible amount ammonia HER. Our work shows that promoting suppressing HER requires optimization operational variables, serves complementary strategy development catalysts.