Scalable synthesis of MoS2 nanosheets electrocatalyst towards high-efficiency nitrite reduction to ammonia

Abstract

Ammonia is a vital chemical raw material for both industry and agriculture, the current ammonia synthesis process is based on the Haber-Bosch process yet faces issues of high-energy consumption and high CO2 emission. Electrochemical nitrite reduction reaction (NO2−RR) has been considered as one of the alternative paths for ammonia synthesis. Here, we develop a large-scale viable route for synthesis of 2H–MoS2 nanosheets (MoS2 NSs), which show high activity as electrocatalyst for high-efficiency conversion of NO2−RR to ammonia, the yields of NH3 production rate reaches as high as 8.99 mg cm−2 h−1 with a faradaic efficiency of 93.52%. A hybrid electrolytic cell is constructed by coupling MoS2 NSs as NO2−RR cathode in neutral electrolyte with oxygen evolution reaction (OER) in alkaline solution, which can operate stably for more than 120 h with the capability of continuously producing ammonia at the production rate of 38.79 mg cm−2 h−1.