Coupling Cu doping and oxygen vacancies in Co 3 O 4 for efficient electrochemical nitrate conversion to ammonia.

Electrochemical conversion of nitrate to NH 3 not only eliminates nitrate pollution in the environment, but also produces highly valuable NH 3 . Herein, Cu-doped Co 3 O 4 with abundant oxygen vacancies (Cu-Co 3 O 4- x ) was prepared on carbon cloth. The as-fabricated Cu-Co 3 O 4- x can selectively reduce nitrate to NH 3 with high Faraday efficiencies (around 90%) and a large NH 3 yield of 0.83 mmol h -1 cm -2 in a neutral electrolyte.