Plasma Activate Nitrogen for Efficient Ammonia Synthesis

Synthetic ammonia is of great significance to the development of industry and agriculture. At present, its manufacturing production is still dominated by century-old Haber-Bosch process, involving in huge amounts of energy consumptions and carbon dioxide emissions. Hence, it is of great significance to develop green and sustainable alternative technologies, such as photo-, thermo-, and electro-catalytic syntheses of ammonia. Nevertheless, the intrinsic inertness of nitrogen results in low ammonia yield of above candidates, which still cannot meet commercialization expectations. Recent researches have successfully demonstrated that plasma can effectively activate the decomposition of nitrogen and hydrogen under ambient conditions, thereby significantly improving the ammonia yield of these alternative strategies. This review systematically summarizes the classification and reaction mechanism of plasma for this reason, and discusses the synergy between different plasma and catalytic methods along with energy consumptions in detail. In the meantime, the future development trend is also forecasted.