Influence of cations on nitrate-to-ammonia synthesis over NiO:SnO2: insights from differential electrochemical mass spectrometry

Abstract

The electrochemical conversion of nitrate to ammonia is crucial for nitrogen upcycling. This study investigates the effect of electrolyte cations (K⁺, Na⁺, and Li⁺) on nitrate electroreduction using NiO:SnO₂ nanofibers. Among other products, in situ differential electrochemical mass spectrometry (DEMS) confirms that NH₃ formation strongly depends on cation identity, inducing a shift in product selectivity from NH₃ to H₂. These results highlight the importance of cation-mediated pathways in aqueous systems and provide insight into ammonia synthesis.