Coupling Cu doping and oxygen vacancies in Co3O4for efficient electrochemical nitrate conversion to ammonia

Electrochemical conversion of nitrate to NH3 not only eliminates nitrate pollution in the environment, but also produces highly valuable NH3. Herein, Cu-doped Co3O4 with abundant oxygen vacancies (Cu-Co3O4-x) was prepared on carbon cloth. The as-fabricated Cu-Co3O4-x can selectively reduce nitrate to NH3 with high Faraday efficiencies (around 90%) and a large NH3 yield of 0.83 mmol h-1 cm-2 in a neutral electrolyte.