Opportunities and Challenges of the Electrosynthesis of Nitrites and Nitrates From Ammonia

Abstract

Electrochemical ammonia oxidation can enable sustainable, distributed synthesis of nitrite and nitrate powered by renewable energy, as an alternative to the centralized Ostwald process. However, the catalyst-centered research struggles to produce ammonia electrooxidation systems delivering faradaic efficiency, yield rates, selectivity, and stability required for industrial implementation. This perspective aims to explore why current strategies fall short, revealing fundamental constraints that could not be resolved by the catalyst design alone so far. Practical nitrite/nitrate yield rates require potentials where oxygen evolution dominates, while harsh operational conditions inevitably cause corrosion of most materials. We suggest that further progress requires an integrated approach at the overall system level, rather than catalyst design under model conditions, and translating studies of the catalytic and degradation mechanisms into a practical operational environment. In turn, this requires electrolyser architectures suitable for robust high-current operation. This article aims to propose future research directions that might address these limitations.