Interface engineering of CoS/MoS 2 heterostructure for the electrocatalytic reduction of N 2 to NH 3

As an environmentally friendly and sustainable method for ammonia synthesis, nitrogen reduction reaction (NRR) by electrocatalysis possesses several advantages, including viability under mild conditions, abundant reaction raw materials and low energy consumption, and thus it is supposed to be a promising alternative to the traditional Haber–Bosch process. However, the stable NN bonds in the nitrogen (N 2 ) and the competing hydrogen evolution reaction (HER) put harsh requirements on catalysts. In this study, the CoS/MoS 2 heterojunction catalyst where CoS nanoparticles are anchored on the MoS 2 nanosheets is reported as a high-efficiency NRR catalyst. The catalysts have high NH 3 yield (23.23 μg h −1 mg cat. −1 ), reasonable faradaic efficiency (FE, 12.63%) and long-term electrochemical stability under −0.45 V vs. RHE in 0.1 M Na 2 SO 4 solution, whose performance is better than MoS 2 and CoS. The TPV results show rapid interfacial electron transfer and good conductivity of the material, and the DFT calculation reveals that the CoS attached to the (100) plane effectively enhances N 2 adsorption and catalysis performance.