Amorphous CoMoO₄ with Nanoporous Structures for Electrochemical Ammonia Synthesis under Ambient Conditions

The nonpollution electrochemical synthesis of NH₃ under ambient conditions is a hopeful candidate to the industrial Haber–Bosch process in harsh conditions. Potential catalyst exploration is very important to improve NH₃ production and Faraday efficiency. Herein, we synthesized amorphous CoMoO₄ catalysts with nanoporous structures by chemical dealloying for the N₂ reduction reaction (NRR). At −0.50 V versus reversible hydrogen electrode, the CoMoO₄ catalyst exhibits a high NH₃ yield of 30.2 μg h^–1 mg_cat^–1 and a Faraday efficiency of 3.8% in 0.1 M phosphate buffer saline. The enhanced NRR property is ascribed to modified structures by a binary metal synergistic effect and more active site exposure because of the amorphous structure. Compared with MoO₂, mixed oxide (MoO₂ and Co₃O₄), and crystal CoMoO₄, binary metallic oxide of amorphous CoMoO₄ is more favorable in N₂ activation and protonation.