Fundamentals, rational catalyst design, and remaining challenges in electrochemical NO reduction reaction

Nitrogen oxides (NO) emissions carry pernicious consequences on air quality and human health, prompting an upsurge of interest in eliminating them from the atmosphere. The electrochemical NO reduction reaction (NORR) is among the promising techniques for NO removal and potential conversion into valuable chemical feedstock with high conversion efficiency while benefiting energy conservation. However, developing efficient and stable electrocatalysts for NORR remains an arduous challenge. This review provides a comprehensive survey of recent advancements in NORR, encompassing the underlying fundamentals of the reaction mechanism and rationale behind the design of electrocatalysts using computational modeling and experimental efforts. The potential utilization of NORR in a Zn-NO battery is also explored as a proof of concept for concurrent NO abatement, NH₃ synthesis, and decarbonizing energy generation. Despite significant strides in this domain, several hurdles still need to be resolved in developing efficient and long-lasting electrocatalysts for NO reduction. These possible means are necessary to augment the catalytic activity and electrocatalyst selectivity and surmount the challenges of catalyst deactivation and corrosion. Furthermore, sustained research and development of NORR could offer a promising solution to the urgent issue of NO pollution, culminating in a cleaner and healthier environment.