Electrochemical Synthesis\nof Nitrite and Nitrate via\nCathodic Oxygen Activation in Liquefied Ammonia

The electrochemical oxidation of ammonia (NH<sub>3</sub>) enables\ndecentralized small-scale synthesis of nitrate (NO<sub>3</sub><sup>–</sup>) and nitrite (NO<sub>2</sub><sup>–</sup>) under\nambient conditions by directly utilizing renewable energy. Yet, their\nelectrosynthesis has been restricted to aqueous media and low ammonia\nconcentrations. For the first time, we demonstrate here a strategy\nenabling the direct electrooxidation of liquefied NH<sub>3</sub> to\nNO<sub>3</sub><sup>–</sup> and NO<sub>2</sub><sup>–</sup> by using molecular oxygen, achieving combined Faraday efficiencies\nabove 40%.