The electrochemical synthesis of ammonia from nitrogen under mild conditions using renewable electricity is an attractive alternative to the energy-intensive Haber–Bosch process, which dominates industrial ammonia production.
Explanation:
However, there are considerable scientific and technical challenges facing the electrochemical alternative, and most experimental studies reported so far have achieved only low selectivities and conversions. The amount of ammonia produced is usually so small that it cannot be firmly attributed to electrochemical nitrogen fixation rather than contamination from ammonia that is either present in air, human breath or ion-conducting membranes, or generated from labile nitrogen-containing compounds (for example, nitrates, amines, nitrites and nitrogen oxides) that are typically present in the nitrogen gas stream, in the atmosphere or even in the catalyst itself. Although these sources of experimental artefacts are beginning to be recognized and managed, concerted efforts to develop effective electrochemical nitrogen reduction processes would benefit from benchmarking protocols for the reaction and from a standardized set of control experiments designed to identify and then eliminate or quantify the sources of contamination.
