落雷からヒントを得たエコフレンドリーな反応器が空気と水をアンモニアに変換（Taking a cue from lightning, eco-friendly reactor converts air and water into ammonia）

2024-12-19 バッファロー大学（UB）

＜関連情報＞

• https://www.buffalo.edu/news/releases/2024/12/eco-friendly-reactor-converts-air-and-water-into-ammonia.html
• https://pubs.acs.org/doi/10.1021/jacs.4c12858

プラズマ電気化学アンモニア合成におけるNOxHy混合反応物質の反応経路制御 Controlling the Reaction Pathways of Mixed NOxHy Reactants in Plasma-Electrochemical Ammonia Synthesis

Xiaoli Ge,Chengyi Zhang,Mayuresh Janpandit,Shwetha Prakash,Pratahdeep Gogoi,Daoyang Zhang,Timothy R. Cook,Geoffrey I.N. Waterhouse,Longwei Yin,Ziyun Wang,and Yuguang C. Li
Journal of the American Chemical Society  Published: December 12, 2024
DOI:https://doi.org/10.1021/jacs.4c12858

Abstract

Electrochemical activation of dinitrogen (N₂) is notoriously challenging, typically yielding very low ammonia (NH₃) production rates. In this study, we present a continuous flow plasma-electrochemical reactor system for the direct conversion of nitrogen from air into ammonia. In our system, nitrogen molecules are first converted into a mixture of NO_x species in the plasma reactor, which are then fed into an electrochemical reactor. To selectively convert the generated NO_x species into NH₃, we employed a graph theory approach combined with first-principles calculations to comprehensively enumerate all possible pathways from N₂-to-NH₃, pinpointing key intermediates (NH₂* and NO*). A series of bimetallic catalysts was then designed to target the optimal adsorption and conversion of the limiting intermediate in the NO_x-to-NH₃ pathway. Using an optimized CuPd foam catalyst, we demonstrated an ammonia production rate of 81.2 mg h^–1 cm^–2 with stability over 1000 h at an applied current of 2 A.