Ambient electrochemical nitrogen fixation with aqueous V2O5 nanodots in a fluidized electrocatalysis system

We report a fluidized electrocatalysis system using V2O5 nanodots (V2O5 NDs) electrocatalyst dispersed in aqueous electrolyte for efficiently ambient electrocatalytic nitrogen reduction reaction (NRR) and nitrogen oxidation reaction (NOR). Compared to the conventional catalyst-immobilized approach, the V2O5 NDs catalyst with such fluidized approach exhibits superior bifunctional activities toward NRR and NOR, affording a high NH3 yield of 575.3 mu g h-1 mg- 1 and a faradaic efficiency (FE) of 28.7 % for NRR and a high NO3- yield of 1388.0 mu g h-1 mg -1 and a FE of 12.6 % for NOR, respectively. The high bifunctional activities of V2O5 NDs are originated from the abundant oxygen vacancies as the active sites for the adsorption and activation of N2, affirmed by the DFT calculations. Furthermore, a theoretical model is built by the Monte Carlo simulation to confirm the important role of nanodots-incorporated fluidized approach in enhancement of mass transport and regeneration of active sites.

Automated summary

A fluidized electrocatalysis system using V2O5 nanodots dispersed in aqueous electrolyte is reported for efficient ambient electrocatalytic nitrogen reduction reaction and nitrogen oxidation reaction. The fluidized approach with V2O5 nanodots catalyst exhibits superior bifunctional activities, yielding high ammonia and nitrate production with good faradaic efficiency. The abundant oxygen vacancies in V2O5 nanodots are identified as the source of its high activity, which is confirmed by DFT calculations.