Electrochemical Synthesis of Nitrite and Nitrate via Cathodic Oxygen Activation in Liquefied Ammonia

The electrochemical oxidation of ammonia (NH(3)) enables decentralized small-scale synthesis of nitrate (NO(3)(-)) and nitrite (NO(2)(-)) under ambient conditions by directly utilizing renewable energy. Yet, their electrosynthesis has been restricted to aqueous media and low ammonia concentrations. For the first time, we demonstrate here a strategy enabling the direct electrooxidation of liquefied NH(3) to NO(3)(-) and NO(2)(-) by using molecular oxygen, achieving combined Faraday efficiencies above 40%.