Selective electroreduction of nitrate to ammonia via NbWO6 perovskite nanosheets with oxygen vacancy

Electrocatalytic nitrate reduction to ammonia (NRA) under ambient conditions is significant for carbon -neutral synthetic fuels. Nevertheless, the lack of efficient electrocatalysts with tunable nanostructure for NRA remains a grand challenge. Herein, NbWO6 nanosheets with oxygen vacancy (NbWO6-x) was demon-strated via thermal treatment and exfoliation with NH3 selectivity of 86.8% and Faradaic efficiency of 85.7% toward NRA. 1 H nuclear magnetic resonance spectra coupled with 15 N isotope labeling experiments proved that NH3 originated from NO3 -. The function of oxygen vacancy was revealed by computational studies in NRA. Moreover, the reaction mechanism and pathway of NRA could be deduced based on the results of online differential electrochemical mass spectrometry (DEMS). This work provides a selective NH3 generation strategy to decarbonize the energy-chemical sector, bridging the gap between batteries and biofuels.(c) 2023 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.