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Lithium–sulfur batteries are recognized as one of the most promising next‐generation energy‐storage technologies owing to their high energy density and low cost. Nevertheless, the shuttle effect of polysulfide intermediates and the formation of lithium dendrites are the principal reasons that restrict the practical adoption of current Li–S batteries. Adjustable frameworks, structural variety, and functional adaptability of covalent organic frameworks (COFs) have the potential to overcome the issues associated with Li–S battery technology. Herein, a summary is presented of emerging COF materials in addressing the challenging problems in terms of sulfur hosts, modified separators, artificial solid electrolyte interphase layers, and solid‐state electrolytes. This comprehensive overview focuses on the design and chemistry of COFs used to upgrade Li–S batteries. Furthermore, existing difficulties, prospective remedies, and prospective research directions for COFs for Li–S batteries are discussed, laying the groundwork for future advancements in this class of fascinating materials.

Novel magnetorheological fluids-supramolecular magnetorheological polymer gels (SMRPGs)-were investigated. Supramolecular polymer deposited on the surface of iron particles was suspended in the carrier fluids. The supramolecular network was obtained by metal coordination between terpyridine monomers and zinc ion. These SMRPGs had such advantages as controllable off-state viscosity, a reduced iron particle settling rate, and stability. The viscoelastic behavior of SMRPGs with small-and largeamplitude oscillatory shear was investigated using the amplitude and frequency sweep mode. The effects of strain amplitude, frequency, and magnetic field strength on the viscoelastic moduli were measured. The linear viscoelastic (LVE) strain range was obtained by the oscillation and static stress strain methods. The maximum LVE value was equal to the preyield strain point, 0.3%. Microstructural variation of SMRPG is proposed as an explanation of the rheological changes in the oscillation tests. The results of this research indicate that off-state viscosity and particle settling can be controlled by adjusting the concentration of supramolecular polymer gel. Dynamic yield stress significantly increased with an external magnetic field up to ϳ23,500 Pa under a magnetic flux density of 500 mT.

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