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Although graphene nanomesh is an attractive 2D carbon material, general synthetic routes to produce functional graphene nanomesh in large‐scale are complex and tedious. Herein, we elaborately design a simple two‐step dimensional reduction strategy for exploring nitrogen‐doped graphene nanomesh by thermal exfoliation of crystal‐ and shape‐modified metal‐organic frameworks (MOFs). MOF nanoleaves with 2D rather than 3D crystal structure are used as the precursor, which are further thermally unraveled into nitrogen‐doped graphene nanomesh by using metal chlorides as the exfoliators and etching agent. The nitrogen‐doped graphene nanomesh has a unique ultrathin two‐dimensional morphology, high porosity, rich and accessible nitrogen‐doped active sites, and defective graphene edges, contributing to an unprecedented catalytic activity for the oxygen reduction reaction (ORR) in acid electrolytes. This approach is suitable for scalable production.

Half reactions of CO 2 RRElectrode potentials E 0 (V vs SHE, pH 7) CO 2 + e − →*CO 2 δˉ− 1.9 CO 2 + 2H + + 2e − →CO −0.52 CO 2 + 2H + +2e − →HCOOH −0.61 CO 2 + 4H + + 4e − →HCHO −0.51 CO 2 + 6H + + 6e − →CH 3 OH −0.38 CO 2 + 6H + + 8e − →CH 4 −0.24 CO 2 + 12H + + 12e − →C 2 H 4 −0.34 2H + + 2e − →H 2 O −0.42

Mesoporous metal sulfide hybrid (meso-MoS2/CoMo2S4) materials via a soft-templating approach using diblock copolymer polystyrene-block-poly­(acrylic acid) micelles are reported. The formation of the meso-MoS2/CoMo2S4 heterostructures is based on the sophisticated coassembly of dithiooxamide and metal precursors (i.e., Co2+, PMo12), which are subsequently annealed in nitrogen atmosphere to generate the mesoporous material. Decomposing the polymer leaves behind mesopores throughout the spherical MoS2/CoMo2S4 hybrid particles, generating numerous electrochemical active sites in a network of pores that enable faster charge transfer and mass/gas diffusion that enhance the electrocatalytic performance of MoS2/CoMo2S4. Doping the spherical meso-MoS2/CoMo2S4 heterostructures with iron improves the electronic properties of the hybrid meso-Fe-MoS2/CoMo2S4 material and consequently results in its superior electrochemical activities for both hydrogen evolution reaction and oxygen evolution reaction.

This work reports two-dimensional nanoporous Co–Nx/C electrocatalysts with high performance for oxygen reduction reaction and zinc–air battery.

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This study demonstrates a special ultrathin N-doped graphene nanomesh (NGM) as a robust scaffold for highly exposed Fe−N 4 active sites. Significantly, the pore sizes of the NGM can be elaborately regulated by adjusting the thermal exfoliation conditions to simultaneously disperse and anchor Fe−N 4 moieties, ultimately leading to highly loaded Fe single-atom catalysts (SA-Fe-NGM) and a highly exposed morphology. The SA-Fe-NGM is found to deliver a superior oxygen reduction reaction (ORR) activity in acidic media (half-wave potential = 0.83 V vs RHE) and a high power density of 634 mW cm −2 in the H 2 /O 2 fuel cell test. First-principles calculations further elucidate the possible catalytic mechanism for ORR based on the identified Fe− N 4 active sites and the pore size distribution analysis. This work provides a novel strategy for constructing highly exposed transition metals and nitrogen co-doped carbon materials (M−N−C) catalysts for extended electrocatalytic and energy storage applications.

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