Dramatically Enhanced Ambient Ammonia Electrosynthesis Performance by In‐Operando Created Li–S Interactions on MoS2 Electrocatalyst

The Haber‐Bosch process can be replaced by the ambient electrocatalytic N₂ reduction reaction (NRR) to produce NH₃ if suitable electrocatalysts can be developed. However, to develop high performance N₂ fixation electrocatalysts, a key issue to be resolved is to achieve efficient hydrogenation of N₂ without interference by the thermodynamically favored hydrogen evolution reaction (HER). Herein, in‐operando created strong Li–S interactions are reported to empower the S‐rich MoS₂ nanosheets with superior NRR catalytic activity and HER suppression ability. The Li⁺ interactions with S‐edge sites of MoS₂ can effectively suppress hydrogen evolution reaction by reducing H* adsorption free energy from 0.03 to 0.47 eV, facilitate N₂ adsorption by increasing N₂ adsorption free energy from –0.32 to –0.70 eV and enhance electrocatalytic N₂ reduction activity by decreasing the activation energy barrier of the reaction control step (*N₂ → *N₂H) from 0.84 to 0.42 eV. A NH₃ yield rate of 43.4 μg h^?1 mg^?1 MoS₂ with a faradaic efficiency (FE) of 9.81% can be achieved in presence of strong Li–S interactions, more than 8 and 18 times by the same electrocatalyst in the absence of Li–S interactions. This report opens a new way to design and develop catalysts and catalysis systems.