Asymmetric Electronic Distribution at Mn–Cu Dual Atomic Sites Promoting Electrochemical Conversion of N 2 to NH 3

Electrochemical synthesis of ammonia (NH₃) is a promising green alternative to the conventional Haber-Bosch process. Here, we report the synthesis of a heteroatomic metal-metal bonded dual atomic (DA) Mn-Cu catalytic site embedded within nitrogen-doped carbon (NC) matrix for high-performance electrochemical reduction of N₂ to NH₃. The asymmetric electronic distribution localized at the dual atomic sites synergistically enhances the adsorption and activation of N₂, facilitating the complex proton-coupled electron transfer process. Compared to single atomic (SA)-Mn/NC, DA-MnCu/NC exhibits a fourfold increase in nitrogen reduction reaction (NRR) performance, achieving a higher Faradaic efficiency of 67.76 ± 0.7% and 88.34 ± 3.6 µg mg_cat ^-1 h^-1 at -0.15 V (versus RHE) in 0.5 M NaBF₄ medium. Furthermore, the catalyst demonstrates long-term stability, retaining its performance over extended operation. This work presents valuable insights into the design of dual atomic catalysts and highlights the critical role of the localized electronic distribution at the catalytic sites in enabling sustainable NH₃ synthesis.