1T-MoS₂ Nanosheets Coupled with CoS₂ Nanoparticles: Electronic Modulation for Efficient Electrochemical Nitrogen...

Electrocatalytic nitrogen reduction reaction (eNRR), a substitute process for the conventional Haber-Bosch for NH₃ production, has drawn tremendous attention due to its merits in mild conditions, abundant reactant sources, low energy consumption, and environmental protection. However, electrocatalysts for eNRR are still subjected to low catalytic activity and selectivity. Herein, we constructed a CoS₂/1T-MoS₂ heterostructure with CoS₂ nanoparticles uniformly loaded on 1T-MoS₂ nanosheets and applied it as an eNRR electrocatalyst for the first time. Theoretical calculation suggests that electron transfer from CoS₂ to 1T-MoS₂ across their contact interface optimizes the local electronic structure of 1T-MoS₂, where the electron-depletion region near CoS₂ is in favor of accepting lone-pair electrons from N₂ to enable N₂ absorption, and the electron-accumulation region near 1T-MoS₂ is conductive to break inert N≡N triple bonds. Unlike pure 1T-MoS₂, the potential-determining step (PDS) demonstrates a significantly lower energy barrier. In addition, the weak interaction between CoS₂/1T-MoS₂ and hydrogen discourages competitive hydrogen evolution reaction. As a result, CoS₂/1T-MoS₂ exhibited noticeably improved eNRR activity and selectivity, with an NH₃ yield of 59.3 μg h^-1 mg^-1 and a high Faradaic efficiency of 26.6%.