Covalent organic frameworks with designable periodic skeletons and ordered nanopores have attracted increasing attention as promising cathode materials for rechargeable batteries. However, the reported cathodes are plagued by limited capacity and unsatisfying rate performance. Here we report a honeycomb-like nitrogen-rich covalent organic framework with multiple carbonyls. The sodium storage ability of pyrazines and carbonyls and the up-to twelve sodium-ion redox chemistry mechanism for each repetitive unit have been demonstrated by in/ex-situ Fourier transform infrared spectra and density functional theory calculations. The insoluble electrode exhibits a remarkably high specific capacity of 452.0 mAh g −1 , excellent cycling stability (~96% capacity retention after 1000 cycles) and high rate performance (134.3 mAh g −1 at 10.0 A g −1). Furthermore, a pouch-type battery is assembled, displaying the gravimetric and volumetric energy density of 101.1 Wh kg −1 cell and 78.5 Wh L −1 cell , respectively, indicating potentially practical applications of conjugated polymers in rechargeable batteries.

Organic carbonyl compounds show potential as cathode materials for lithium‐ion batteries (LIBs) but the limited capacities (<600 mA h g−1) and high solubility in electrolyte restrict their further applications. Herein we report the synthesis and application of cyclohexanehexone (C6O6), which exhibits an ultrahigh capacity of 902 mA h g−1 with an average voltage of 1.7 V at 20 mA g−1 in LIBs (corresponding to a high energy density of 1533 Wh kg−1normalC6normalO6 ). A preliminary cycling test shows that C6O6 displays a capacity retention of 82 % after 100 cycles at 50 mA g−1 because of the limited solubility in high‐polarity ionic liquid electrolyte. Furthermore, the combination of DFT calculations and experimental techniques, such as Raman and IR spectroscopy, demonstrates the electrochemical active C=O groups during discharge and charge processes.

Copper nanoparticles dispersed rod-shaped La 2 O 2 CO 3 efficiently catalyzed transfer dehydrogenation of primary aliphatic alcohols with an aldehyde yield of up to 97%. This high efficiency was achieved by creating a catalytically active nanoenvironment for effective reaction coupling between alcohol dehydrogenation and styrene hydrogenation via hydrogen transfer. The {110} planes on the La 2 O 2 CO 3 nanorods not only provided substantial amounts of medium-strength basic sites for the activation of alcohol but also directed the selective dispersion of hemispherical Cu particles of about 4.5 nm on their surfaces, which abstracted and transferred hydrogen atoms for styrene hydrogenation. This finding provides a new strategy for developing highly active alcohol-dehydrogenation catalysts by tuning the shape of the oxide support and consequently the metal-oxide interfacial nanostructure.

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