Metal–organic frameworks (MOFs) or covalent–organic frameworks (COFs) have gained increasing attentions due to their high surface area, tunable structure, highly ordered pores and functional composition. Besides their applications in gas adsorption and separation, hydrogen storage, optics, magnetism and drug delivery, they have been widely employed as cathodes, anodes and separators for the research and development in lithium‐ion batteries (LIBs) due to the tunable structure, multi‐electron transfer, short pathway, and robust structural stability, etc. This review summarizes the general applied strategies and cases of MOF, COF and their composites as well as derivatives in LIBs. Compared to inorganic materials, the advantages of MOF/COF materials have made it possible to witness various successful cases with enhanced electrochemical performances. Moreover, this review provides some guidance for the controllable preparation and modification of MOF‐ and COF‐derived nanostructures through molecular engineering, rational design, and doping, as well as functional group modifications. In addition, we highlight timely progresses of the application of organic frameworks in LIBs, and also summarize many strategies of MOF/COF materials and their derivatives on enhancing the energy density, diffusion coefficient, rate performance and cycling stability for next‐generation LIBs with attractive features of high energy density, good rate performance, and superior cyclability.

Metal–selenium (M–Se) batteries are considered promising candidates for next‐generation battery technologies owing to their high energy density and high‐rate capability. However, Se cathode suffers from poor cycling performance and low Coulombic efficiency, owing to the shuttle effect of polyselenides. Herein, it is reported the incorporation of Ti3C2Tx MXene onto Se infiltrated porous N‐doped carbon nanofibers (PNCNFs) to construct free‐standing Janus PNCNFs/Se@MXene cathodes for high‐performance Na–Se and Li–Se batteries. The increase of pyrrolic‐N content and the porous structure of the PNCNFs is conducive to enhancing the adsorption of Na2Se and alleviating the shuttle effect. Meanwhile, density functional theory (DFT) calculations have proven that 2D Ti3C2Tx MXene with polar interfaces enables the effective chemical immobilization and physical blocking of polyselenides to suppress the shuttle effect. The unique architecture with Ti3C2Tx MXene built on top of interlinked nanofiber ensures the continuous electron transfer for redox reaction. As a result, the novel Janus PNCNFs/Se@MXene electrodes deliver robust rate capabilities and superior long‐term cycling stability in both Na–Se and Li–Se batteries. The incorporation of 2D MXene to construct Janus electrodes provides a competitive advantage for selenium‐based cathode materials and highlights a new strategy for developing high‐performance batteries.

in situ X-ray diffraction (XRD), ionic codoping, Li 3 V 2 (PO 4 ) 3 , theoretical calculations, wide temperature range

Lithium‐sulfur battery (LSB) is widely regarded as the most promising next‐generation energy storage system owing to its high theoretical capacity and low cost. However, the practical application of LSBs is mainly hampered by the low electronic conductivity of the sulfur cathode and the notorious “shuttle effect”, which lead to high voltage polarization, severe over‐charge behavior, and rapid capacity decay. To address these issues, a novel sulfur reservoir is synthesized by coating polypyrrole (PPy) thin film on hollow layered double hydroxide (LDH) (PPy@LDH). After compositing with sulfur, such PPy@LDH‐S cathode shows a multi‐functional effect to reserve lithium polysulfides (LiPSs). In addition, the unique architecture provides sufficient inner space to encapsulate the volume expansion and enhances the reaction kinetics of sulfur‐based redox chemistry. Theoretical calculations have illustrated that the PPy@LDH has shown stronger chemical adsorption capability for LiPSs than those of porous carbon and LDH, preventing the shuttling of LiPSs and enhancing the nucleation affinity of liquid‐solid conversion. As a result, the PPy@LDH‐S electrode delivers a stable cycling performance and a superior rate capability. Flexible battery has demonstrated this PPy@LDH‐S electrode can work properly with treatments of bending, folding, and even twisting, paving the way for wearable devices and flexible electronics.