Selective electrosynthesis of ammonia via nitric oxide electroreduction catalyzed by copper nanowires infused in nitrogen-doped carbon nanorods

Abstract

The electrochemical nitric oxide reduction reaction (eNORR) is meticulously investigated as an alternative to the energy intensive Haber-Bosch process to produce Ammonia (NH). However, the eNORR is hindered by NH selectivity due to side reactions and mass-transfer limitations. In this work, we rationally designed copper nanowires (Cu NWs) infused in the lotus-root-like multi-nano-channels of the porous N-doped carbon nanorods (Cu-mNCNR) for a high selective eNORR to synthesize NH at ambient conditions. The optimized catalyst, Cu-mNCNR2, has achieved the highest NH Faradaic efficiency of 79% with NH yield rate of 34.5 μmol cm h at −0.4 V. Moreover, the Cu-mNCNR2 has demonstrated a vigorous performance in the 24 h continuous NO electrolysis to produce NH. Additionally, a prototype device, the Zn-NO battery, was demonstrated. This study shows that the rational design of a catalyst considering mass-transfer limitations is crucial to achieving high selective NH electrosynthesis in eNORR.