Ag nanosheets for efficient electrocatalytic N2 fixation to NH3 under ambient conditions†
The industrial-scale NH3 production still heavily depends on the Haber–Bosch process which demands not only high energy consumption but emits a large amount of CO2. Electrochemical fixation of N2 to NH3 under ambient conditions is regarded as an eco-friendly and sustainable approach, but stable and efficient electrocatalysts are demanded for the N2 reduction reaction (NRR). In this work, we report our recent finding that an Ag nanosheet acts as a high-performance NRR electrocatalyst at room temperature and pressure. Electrochemical tests in 0.1 M HCl reveal that such a catalyst achieves a high Faradaic efficiency of 4.8% and a NH3 yield rate of 4.62 × 10−11 mol s−1 cm−2 at −0.60 V vs. reversible hydrogen electrode (RHE), rivaling the performances of most of the reported aqueous-based NRR electrocatalysts. Additionally, the Ag nanosheet also shows excellent selectivity, strong long-term electrochemical stability and durability.