Exploring high-efficiency and earth-abundant bifunctional electrocatalysts for overall water splitting is of great significance to meet the requirement of the hydrogen economy, but still faces many challenges. In this work, we propose the chemical etching, successive carbonization, and phosphorization treatment strategy of solid ZIF-67 (ZIF = zeolitic imidazole framework), constructing a hybrid nanostructure with CoP nanoparticles embedded in a hollow N-doped carbon nanocage (h-CoP@NC). The elaborate hollow porous structure is conducive to effectively exposing more active sites and shortening mass-transportation pathways. The nitrogen-doped carbon layer would protect the active CoP units from agglomeration and enhance the conductivity. These structural factors synergistically contribute to the enhanced electrocatalytic performance. As a result, the carbonization-temperature-optimized

Electrochemical N 2 reduction reaction (NRR) emerges as a highly attractive alternative to the Haber-Bosch process for producing ammonia (NH 3 ) under ambient circumstances. Currently, this technology still faces tremendous challenges due to the low ammonia production rate and low Faradaic efficiency, urgently prompting researchers to explore highly efficient electrocatalysts. Inspired by the Fe−Mo cofactor in nitrogenase, we report Mo-doped hematite (Fe 2 O 3 ) porous nanospheres containing Fe-O-Mo subunits for enhanced activity and selectivity in the electrochemical reduction from N 2 to NH 3 . Mo-doping induces the morphology change from a solid sphere to a porous sphere and enriches lattice defects, creating more active sites. It also regulates the electronic structures of Fe 2 O 3 to accelerate charge transfer and enhance the intrinsic activity. As a consequence, Mo-doped Fe 2 O 3 achieves effective N 2 fixation with a high ammonia production rate of 21.3 ± 1.1 μg h −1 mg cat.−1 as well as a prominent Faradaic efficiency (FE) of 11.2 ± 0.6%, superior to the undoped Fe 2 O 3 and other iron oxide catalysts. Density functional theory (DFT) calculations further unravel that the Mo-doping in Fe 2 O 3 (110) narrows the band gap, promotes the N 2 activation on the Mo site with an elongated N�N bond length of 1.132 Å in the end-on configuration, and optimizes an associative distal pathway with a decreased energy barrier. Our results may pave the way toward enhancing the electrocatalytic NRR performance of iron-based materials by atomic-scale heteroatom doping.

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Lithium metal is regarded as “holy grail” in the secondary rechargeable batteries. However, irregular Li deposition and dead lithium during the plating/striping process lead to serious safety issues and rapid capacity decay. The low conductivity of matrix and inhomogeneous ion transfer result in the growth of lithium dendrite and thus the low coulombic efficiency. Here, the authors propose to solve this issue by constructing highly conductive matrix with regulated charge transfer. A low surface tension (LST) strategy is adopted to construct ultrathin reduced graphene oxide (UrGO) to storage Li. The ultrathin and loose structure promise UrGO with high conductivity and the uniformly distributed residue oxygen‐containing groups helps to induce the uniform deposition of lithium due to the improved affinity to Li. The obtained UrGO with high conductivity shows a low lithium nucleation overpotential. The UrGO@Li electrode reveals an outstanding electrochemical stability with a high coulombic efficiency of 98.5% for over 300 cycles. The good performances of full cell also indicate the successful design of the UrGO matrix and the LST strategy provides a new vision for designing highly conductive graphene‐based porous materials.