Electrochemical nitrate reduction to ammonia is a promising alternative strategy to the traditional Haber-Bosch process but suffers from a low Faradaic efficiency and limited ammonia yield due to the sluggish multi-electron/proton-involved steps. Herein, we report a typical hollow cobalt phosphide nanosphere electrocatalyst assembled on a self-supported carbon nanosheet array synthesized with a confinement strategy that exhibits an extremely high ammonia yield rate of 8.47 mmol h−1 cm−2 through nitrate reduction reaction, which is highly superior to previously reported values to our knowledge. In situ experiments and theoretical investigations reveal that the dynamic equilibrium between the generation of active hydrogen on cobalt phosphide and its timely consumption by nitrogen intermediates leads to a superior ammonia yield with a high Faradaic efficiency. This unique insight based on active hydrogen equilibrium provides new opportunities for large-scale ammonia production through electrochemical techniques and can be further used for carbon dioxide capture.

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Highly efficient and low‐cost electrodes have a key role in the development of advanced energy devices such as fuel cells and metal–air batteries. However, electrode performance is typically limited by low utilization of active sites, which causes a considerable drop in energy density. To overcome this issue, a single‐atom‐containing integrated electrode is developed through a confinement synthesis strategy by using organic molecule‐intercalated layered double hydroxides (LDHs) as precursors. The as‐prepared integrated electrode has a well‐defined nanosheet array structure with a homogeneous anchored single atomic Co catalyst and many exposed hierarchical pores. Moreover, the coordination environment of single atoms (CoN or CoS) is precisely controlled by regulating the type of interlayer molecules in the LDHs. Consequently, the optimized electrode exhibits high bifunctional activity toward both the oxygen reduction and oxygen evolution reactions. This electrode is directly assembled into an all‐solid‐state zinc–air battery that showed outstanding flexibility and long‐term charge/discharge stability. Because of the versatility of LDH materials, it is expected that the proposed strategy can be extended to the construction of other integrated electrodes for high‐performance energy storage and conversion devices.

The development of safe lithium‐metal anodes is crucial for the next‐generation rechargeable batteries. To stabilize Li metal anodes, pre‐planting Li nucleation seeds on lithiophilic substrates is an efficient strategy to regulate initial nucleation process of Li metal. Now, activated ultrathin layered double hydroxide (U‐LDHs) are reported as a promising lithiophilic 2D material to realize the uniform deposition of Li metal. The experimental studies and DFT calculations reveal that the active oxygen on U‐LDHs provides abundant atomic‐scale active sites for Li homogeneous nucleation and plating. Moreover, the lithiophilic properties of active oxygen is also related to its coordination environments. This work opens up an opportunity to more accurate regulation and understanding of Li nucleation from atomic‐scale based on 2D ultrathin materials.

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