Gupta Tarisha, Saraswat Shivani, Mondal Anirban, Mondal Biswajit
Department of Chemistry, IIT Gandhinagar Palaj Gujarat-382055 India
Chem Sci. 2025 Jul 2. doi: 10.1039/d5sc00730e.
Ammonia (NH) is a promising carbon-free energy carrier due to its high energy density and hydrogen storage capacity. Its utilization in energy systems relies on the ammonia oxidation reaction (AOR), which is critical for direct ammonia fuel cells (DAFCs) and hydrogen production. Herein, we explore a robust and inexpensive ferrocene-based molecular electrochemical mediator, -pyridylferrocenecarboxamide (Fcpy), for AOR. The Fcpy-mediated AOR exhibits the N faradaic efficiency (FE) of 94.7%, along with the concomitant production of H (FE = 87.3%). Mechanistic studies reveal the crucial role of H-bonding through the pyridyl moiety of Fcpy in facilitating N-H bond activation. Computational analysis further corroborates the observed reaction pathways, providing deeper insights. This work highlights the potential of molecular catalysts to advance ammonia oxidation and underscores their role in sustainable energy systems.
氨（NH₃）因其高能量密度和储氢能力而成为一种很有前景的无碳能源载体。它在能源系统中的应用依赖于氨氧化反应（AOR），这对于直接氨燃料电池（DAFCs）和制氢至关重要。在此，我们探索了一种用于AOR的稳健且廉价的基于二茂铁的分子电化学介质，即β-吡啶基二茂铁甲酰胺（Fcpy）。Fcpy介导的AOR表现出94.7%的N法拉第效率（FE），同时伴有H₂的产生（FE = 87.3%）。机理研究揭示了通过Fcpy的吡啶基部分形成的氢键在促进N - H键活化中的关键作用。计算分析进一步证实了观察到的反应途径，提供了更深入的见解。这项工作突出了分子催化剂在推进氨氧化方面的潜力，并强调了它们在可持续能源系统中的作用。
