Electron coupled FeS2/MoS2 heterostructure for efficient electrocatalytic ammonia synthesis under ambient conditions

Abstract

Developing efficient ammonia synthesis technology under ambient conditions is of vital importance. In this work, an FeS₂ coupled MoS₂ heterostructure with ultrathin features was designed by a one-step hydrothermal process for the electrochemical nitrogen reduction reaction. Density functional theory calculations reveal that the electronic structure of MoS₂ greatly changes with the introduction of FeS₂. The modulated electronic structure of MoS₂ not only exhibits enhanced conductivity but also facilitates the activation of N₂ molecules due to its abundant electronic region. The optimized FeS₂/MoS₂ nanosheet heterostructure achieves a high NH₃ yield rate of 2.59 μmol h⁻¹ mg⁻¹ and a FE of 4.63% at −0.3 V vs. RHE. Besides, the well-designed nanocomposite also shows excellent selectivity without N₂H₄ by-products and exhibits good stability after electrocatalysis for 48 hours.