Redox-active organic cathode materials have drawn growing attention because of the broad availability of raw materials, eco-friendliness, scalable production, and diverse structural flexibility. However, organic materials commonly suffer from fragile stability in organic solvents, poor electrochemical stability in charge/discharge processes, and insufficient electrical conductivity. To address these issues, using Cu(II) salt and benzenehexathiolate (BHT) as the precursors, we synthesized a robust and redox-active 2D metal−organic framework (MOF), [Cu 3 (C 6 S 6 )] n , namely, Cu-BHT. The Cu-BHT MOFs have a highly conjugated structure, affording a high electronic conductivity of 231 S cm −1 , which could further be increased upon lithiation in lithium-ion battery (LIB) applications. A reversible four-electron reaction reveals the Li storage mechanism of the Cu-BHT for a theoretical capacity of 236 mAh g −1 . The as-prepared Cu-BHT cathode delivers an excellent reversible capacity of 175 mAh g −1 with ultralow capacity deterioration (0.048% per cycle) upon 500 cycles at a high current density of 300 mA g −1 . Therefore, we believe this work would provide a practical strategy for the development of highpower energy storage materials.

Searching new organic cathode materials to address the issues of poor cycle stability and low capacity in lithium ion batteries (LIBs) is very important and highly desirable. In this research, a 2D boroxine‐linked chemically‐active pyrene‐4,5,9,10‐tetraone (PTO) covalent organic framework (2D PPTODB COFs) was synthesized as an organic cathode material with remarkable electrochemical properties, including high electrochemical activity (four redox electrons), safe oxidation potential window (between 2.3 and 3.08 V vs. Li/Li+), superb structural/chemical stability, and strong adhesiveness. A binder‐free cathode was obtained by mixing 70 wt % PPTODB and 30 wt % carbon nanotubes (CNTs) as a conductive additive. Promoted by the fast kinetics of electrons/ions, high electrochemical activity, and effective π–π interaction between PPTODB and CNTs, LIBs with the as‐prepared cathode exhibited excellent electrochemical performance: a high specific capacity of 198 mAh g−1, a superb rate ability (the capacity at 1000 mA g−1 can reach 76 % of the corresponding value at 100 mA g−1), and a stable coulombic efficiency (≈99.6 % at the 150th cycle). This work suggests that the concept of binder‐free 2D electroactive materials could be a promising strategy to approach energy storage with high energy density.

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Recent progress in the usage of metal organic polymers (coordination polymers (CPs), metal–organic frameworks (MOFs), Prussian blue and Prussian blue analogues (PBAs)) as electrodes in Li/Na rechargeable batteries has been reviewed.

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Polybenzimidazoles are engineering plastics with superb thermal stability and this specificity has sparked awideranging research to explore proton-conducting materials. Nevertheless,s uch materials encounter challenging issues owingt op hosphoric acid proton carrier leakage and slow proton transport. We report as trategy for designing porous polybenzimidazole frameworks to address these key fundamental issues.T he built-in channels are designed to be onedimensionally extended, unidirectionally aligned, and fully occupied by neat phosphoric acid, while the benzimidazole walls trigger multipoint, multichain, and multitype interactions to spatially confine ap hosphoric acid network in pores and facilitate proton conduction via deprotonation. The materials exhibit ultrafast and stable proton conduction for lowp roton carrier content and activation energy-a set of features highly desired for proton transport. Our results offer adesign strategy for the fabrication of porous polybenzimidazoles for use in energy conversion applications.