Plasma-Activated Electrolysis for Cogeneration of Nitric Oxide and Hydrogen from Water and Nitrogen

Abstract

With increasing global interest in renewable energy technology given the backdrop of climate change, storage of electrical energy has become particularly relevant. Most sustainable technologies (e.g., wind and solar) produce electricity intermittently. Thus, converting electrical energy and base molecules (i.e., H2O, N2) into energy-rich ones (e.g., H2, NH3) or chemical feedstock (e.g., NO) is of paramount importance. While H2O splitting is compatible with renewable electricity, N2 fixation is currently dominated by thermally activated processes. In this work, we demonstrate an all-electric route for simultaneous NO and H2 production. In our approach, H2O is reduced to H2 in the cathode of a solid oxide electrolyzer while NO is produced in the anode by the reaction of O2– species (transported via the electrolyte) and plasma-activated N2 species. High faradaic efficiencies up to 93% are achieved for NO production at 650 °C, and NO concentration is >1000 times greater than the equilibrium concentration at the same temperature and pressure.