Heteronuclear dual‐site catalysts (HDACs), inspired from single‐atom catalyst, have been proposed as advanced alternatives of noble metal catalyst, especially toward nitrogen reduction reaction (NRR). However, the search for favorable candidates with both promising NH3 yield and noble Faradaic efficiency is still challenging, due to limited experimentally available bi‐metal pairs and lack of thorough understanding of the design criteria. Herein, by theoretical screening of a family of M/Fe combinations (M = Sc, Ti, V, Cr, Mn, Co, and Ni), atomically dispersed binary V/Fe architecture anchored on nitrogen‐doped carbon matrix (VFe/NC) is proposed with a small limiting potential (0.39 V) and high selectivity over the hydrogen evolution reaction (HER). Owing to a perfect matching with N2 antibonding state, V 3dz2 orbitals, “push” electrons into adsorbed N2 antibonding stats and simultaneously Fe 3dyz “pull” extra electrons back. Benefiting from the synergistic effect from the dual‐active sites, an outstanding NH3 yield of 73.44 μg h−1 mgcat−1 (8070.32 μg h−1 mgVFe−1) and an excellent Faradaic efficiency of 43% are achieved, overwhelming literature‐reported atomic‐level catalysts. This study promotes the development of HDACs that are capable of high yield rate accompanied with high Faradaic efficiency.

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Potassium-ion batteries (PIBs) are considered as a promising technology alternative to lithium-ion batteries due to more abundance of potassium than lithium and a lower redox potential of K/K+ than that of Na/Na+. The critical limitation in PIBs is the electrode with poor rate capability and cycling stability induced by the sluggish reaction kinetics and large volume change during potassiation and depotassiation. In this work, we report a turbostratic lattice iodine-doped carbon (TLIC) nanosheet as an advanced innovative anode for PIBs displaying fast charge/discharge and electrode stability. The turbostratic lattice caused by doping of large-sized iodine and the unique charge transfer between iodine/carbon atoms creates more active sites and a shorter transport distance for K ions, improves the electrochemical activity, promotes rapid ion diffusion, and enhances pseudocapacitive behavior. The TLIC exhibits a high capacity of 433.5 mAh g–1 at 50 mA g–1, an ultrahigh rate capability of 162.1 mAh g–1 at 20 A g–1, and an excellent capacity retention of ∼96% (206 mAh g–1) after 4000 cycles. The combination of turbostratic lattice and pseudocapactive storage is an effective approach to designing carbon electrodes with the transformational performance of high capacity, rate performance, and long lifetime for practical applications of PIBs.

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