Electrochemical Reduction of N2 to NH3 at Low Potential by a Molecular Aluminum Complex

Electrochemical generation of ammonia (NH3) from nitrogen (N-2) using renewable electricity is a desirable alternative to current NH3 production methods, which consume roughly 1 % of the world's total energy use. The use of catalysts to manipulate the required electron and proton transfer reactions with low energy input is also a chemical challenge that requires development of fundamental reaction pathways. This work presents an approach to the electrochemical reduction of N-2 into NH3 using a coordination complex of aluminum(III), which facilitates NH3 production at -1.16 V vs. SCE. Reactions performed under N-15(2) liberate (NH3)-N-15. Electron paramagnetic resonance spectroscopic characterization of a reduced intermediate and investigations of product inhibition, which limit the reaction to sub-stoichiometric, are also presented.