Ambient electrochemical NH₃ synthesis from N₂ and water enabled by ZrO₂ nanoparticles

Industrially, artifical N₂ fixation to NH₃ mainly relies on the Haber-Bosch process which is operated in a harsh environment with large energy consumption and heavy serious greenhouse gas emission. Electrochemical N₂ reduction offers a carbon-neutral and energy-saving method for NH₃ synthesis under ambient conditions. Herein, we demonstrate the first use of ZrO₂ nanoparticles as an earth-abundant electrocatalyst for NH₃ synthesis from N₂ and water under ambient conditions. In 0.1 M HCl, the electrocatalyst presents a large NH₃ yield rate of 24.74 μg h^-1 mg_cat.^-1 with a faradaic efficiency of 5.0% at -0.45 V vs. the reversible hydrogen electrode. It also demonstrates high electrochemical stability and excellent selectivity for NH₃ generation.