Ar-plasma enhanced copper-nickel alloy catalysis for ammonia synthesis

Ammonia (NH₃) synthesis via electrocatalytic nitrogen reduction generally suffers from low NH₃ yield and faradaic efficiency. Compared with activating stable, low-solubility N₂, the electrochemical conversion of nitrates to ammonia provides a more reasonable route for NH₃ production. Herein, we introduce Ar-plasma to enhance the interaction between copper-nickel alloys and carbon substrate to improve the performance of NH₃ production. The NH₃ faradaic efficiency from nitrate is nearly 100% and the yield rate is over 6000 \({\mathrm{\mu g}}_{{\mathrm{NH}}_{3}}{\mathrm{cm}}^{-2}{\mathrm{h}}^{-1}\). DFT (density functional theory) calculation reveals the high performance of Cu₅₀Ni₅₀ originates from the lower energy barrier on the reaction path and the closer position to the Fermi level of the d-band center. This work offers a promising strategy for plasma-modified electrocatalyst to promote ammonia synthesis via nitrate reduction.