Enhancing the Role of Adsorbed Hydrogen on NiCoP for Electrocatalytic Reduction of Air Plasma‐Derived NO2− to Ammonia

Abstract A transformative NH 3 synthesis technology that utilizes air and H 2 O as raw materials is essential for sustainable development. However, current electrocatalytic NH 3 synthesis technologies relying on N 2 or NO x as feedstock encounter significant challenges, including poor activation of N 2 and unsustainable sourcing of NO x , respectively. Herein, a complete NH 3 synthesis technology is developed by integrating spark discharge plasma for the conversion of air‐to‐NO 2 − , electrocatalytic reduction of NO 2 − ‐to‐NH 3 (pAO‐eNO 2 − RR) using a NiCoP catalyst, and real‐time NH 3 separation process. During this system, the NiCoP catalyst achieves exceptional NH 3 yield of 158.2 mg cm −2 h −1 (9.3 mmol cm −2 h −1 ) and an extremely high Faradaic efficiency of 99.7% for electrocatalytic NO 2 − ‐to‐NH 3 . The pAO‐eNO 2 − RR system demonstrates a highly stable operation at a current density exceeding 1.27 A cm −2 for 100 h. The increased NH 3 yield rate is attributed to the NiCo sites, which enhance the production of essential adsorbed hydrogen acting as carriers for both electrons and protons, thereby enabling the efficient and rapid transfers of multiple electrons and protons. This study enhances the current state of continuous NH 3 synthesis, thus paving the way for the advancement of pAO‐eNO x RR technology toward pilot‐scale research.