Ag nanosheets for efficient electrocatalytic N2 fixation to NH3 under ambient conditions

Abstract

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.