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Ultrathin two‐dimensional (2D) metal‐organic nanosheets (MONs) have attracted continued attention in the field of advanced functional materials. Their nanoscale thickness, high surface‐to‐volume ratio, and abundant accessible active sites, are superior advantages compared with their 3D bulk counterparts. Bioinspired molecular scalpel strategy is a promising method for the creation of 2D MONs, and may solve the current shortcomings of MONs synthesis. This review aims to provide a state‐of‐the‐art overview of molecular scalpel strategies and share the results of current development to provide a better solution for MONs synthesis. Different types of molecular scalpel strategies have been systematically summarized. Both mechanisms, advantages and limitations of multiform molecular scalpel strategies have been discussed. Besides, the challenges to be overcome and the question to be solved are also introduced. [ABSTRACT FROM AUTHOR]

The production of metal–organic framework (MOF) nanoplates with well‐defined geometric morphology is remarkable for expanding their applications. Herein, the cobalt‐based MOF nanoplates with hexagonal channels from a layer‐pillared MOF are accomplished, via a molecular scalpel strategy, utilizing monodentate pyridine to replace the bidentate 4,4′‐bipyridine. The morphology can be modified from nanorods to nanoplates with controllable thickness tuned by the amounts of pyridine. Succeeding carbonization treatment transforms the MOF nanoplates into Co particles homogeneously encapsulated in the nitrogen‐doped carbon layers. The prepared catalyst with a unique platelike morphology displays a high half‐wave potential of 0.88 V in oxygen reduction reaction. When used in primary Zn−air batteries, it delivers a high peak power density of 280 mW cm−2. This work clarifies the structure‐morphology‐reactivity connection of MOF nanoplates. [ABSTRACT FROM AUTHOR]

For rechargeable Zn–air batteries, it is still a great challenge to design a safe and efficient bifunctional oxygen catalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this paper, an ultrasmall Ni3Fe alloy electrocatalyst embedded in nitrogen-doped carbon (denoted as Ni3Fe-NCNTs-800) was obtained by pyrolysis of Ni-MOF hybridized with ferrocene and assisted by melamine in an argon atmosphere at 800 °C. Metal–organic framework (MOF) precursors serve as cages to exert synergistic effects with melamine to limit the aggregation of metal particles, which is a promising strategy for the preparation of advanced oxygen catalysts. Ni3Fe-NCNTs-800 exhibits excellent electrochemical catalytic performance with an ORR (half-wave potential: 0.862 V) and OER (overpotential: 353 mV@10 mA cm−2) potential gap of 0.72 V. Density functional theory (DFT) calculations validate that the strong synergistic coupling of Ni3Fe bimetal plays a key role in lowering the reaction barrier and promoting the reversible oxygen reaction. In addition, liquid Zn–air batteries assembled with Ni3Fe-NCNTs-800 as the air cathode catalyst have ultra-high peak power density (211 mW cm−2 at 240 mA cm−2), specific battery capacity (806 mA h gZn−1), and robust cycle stability (no obvious decay after more than 1350 charge–discharge cycles), which are superior to commercial Pt/C + RuO2 based Zn–air batteries. And three all-solid-state ZABs connected in series can successfully light a LED (∼2.2 V), demonstrating their great potential in portable devices. [ABSTRACT FROM AUTHOR]

The rational design of advanced oxygen reduction reaction (ORR) catalysts is essential to improve the performance of energy conversion devices. However, it remains a huge challenge to construct hierarchical micro-/meso-/macroporous nanostructures, especially mesoporous transport channels in catalysts, to enhance catalytic capability. Herein, motivated by the characteristics of energetic metal-organic frameworks (EMOFs) that produce an abundance of gases during high-temperature pyrolysis, we prepared a unique tetrazine-based EMOF-derived electrocatalyst (denoted as Fe 3 C@NSC-900) consisting of highly dispersed Fe 3 C nanoparticles and N,S-codoped mesoporous carbon nanotubes. The mesopore-dominated core-shell structure endows Fe 3 C@NSC-900 with excellent catalytic activity and efficient mass transfer. Thus, optimal Fe 3 C@NSC-900 demonstrates a high half-wave potential of 0.922 V and great stability in 0.1 M KOH, outperforming commercial Pt/C and most of the reported ORR catalysts. As far as we know, this work is the first application of a tetrazine-based EMOF derivative for the electrocatalytic ORR and is expected to offer some constructive insights into potential of EMOFs for new-generation catalyst design.