Recent Advances and Fundamental Challenges in Computational Modeling of Electrocatalytic Ammonia Oxidation
Rachel Perez, Yang Huang, Hemanth Somarajan Pillai, Hongliang Xin
Abstract
Ammonia (NH 3 ) oxidation is central to the global nitrogen cycle, a delicate natural system that is now disrupted by human activities. The electrocatalytic ammonia oxidation reaction (AOR) to dinitrogen (N 2 ) presents a promising avenue not only for the green remediation of wastewater but also as a sustainable energy vector for the future. In this Perspective, we delve into the intricacies of AOR, highlighting the unique properties of platinum (Pt) as the best elemental metal catalyst, albeit with high overpotential and rapid deactivation. Computational chemistry as a powerful tool has provided deep insights into the nature of active sites and the elementary reaction steps of electrochemical NH 3 oxidation. We describe the structure sensitivity of this reaction with (100)-type site motifs favorable for N–N bond formation via dimerization while also touching upon the role of adsorbed hydroxyl species in dehydrogenation pathways. Addressing surface deactivation is emphasized as paramount for designing improved catalytic materials. This Perspective presents a holistic view of the recent advances, challenges, and future opportunities in computational modeling of AOR or interfacial charge transfer reactions in general, providing a roadmap for future research and innovations.