Development of a Nitrogen-Selective Electrode Catalyst for Electrochemical Ammonia Synthesis from Water and Nitrogen at Low Temperature and Atmospheric Pressure

Ammonia, synthesized by hydrogenation of nitrogen (i.e. Haber-Bosch process) under high pressure (150-300 bar) and high temperature (350-550 ℃), is currently produced and consumed more than 150 million tons annually and its annual production rate is expected to increase by 2.3%. The industrial Haber-Bosch process consumes 1% of world energy production and emits> 270 billion tons of CO₂ annually. As a promising alternative to the Haber-Bosch process, extensive research on electrochemical synthesis of ammonia from water and nitrogen at low temperature and atmospheric pressure have been actively conducted. However, this method is impeded by poor ammonia formation rate and faradaic efficiency at low temperatures < 100^oC and atmospheric pressure because of low nitrogen selectivity and slow reaction rate of hydrogenation.

In this study, a carbon-metal oxide composite electrocatalyst was synthesized, tested, and analyzed under different applied potentials and temperatures < 100^oC at atmospheric pressure.