Manganese-based materials are essential for developing safe, cost-effective, and environmentally sustainable rechargeable batteries, which are critical for advancing clean energy technologies. However, the high spin state of the Mn cation triggers a pronounced Jahn-Teller effect and phase transformations during cycling, leading to structural instability and reduced electrochemical performance of the Mn-based cathodes. This review provides a fundamental understanding of the Jahn-Teller effect, highlights recent strategies to mitigate the high spin state of Mn, and offers insights into future research directions aimed at overcoming the Jahn-Teller effect to enhance the performance of next-generation Mn-based cathodes for rechargeable batteries.

Manganese-based materials are essential for developing safe, cost-effective, and environmentally sustainable rechargeable batteries, which are critical for advancing clean energy technologies. However, the high spin state of the Mn cation triggers a pronounced Jahn-Teller effect and phase transformations during cycling, leading to structural instability and reduced electrochemical performance of the Mn-based cathodes. This review provides a fundamental understanding of the Jahn-Teller effect, highlights recent strategies to mitigate the high spin state of Mn, and offers insights into future research directions aimed at overcoming the Jahn-Teller effect to enhance the performance of next-generation Mn-based cathodes for rechargeable batteries.

Polymer nanofibers have become highly adaptable and versatile one-dimensional nanomaterials due to their large surface area, tunable porosity, mechanical flexibility, and ease of functionalization. Researchers discover a wide range of applications of polymer nanofiber in biomedical, environmental, and energy fields. This review highlights developments to the synthesis, properties, and multifunctional uses of polymer nanofibers and focuses on various fabrication approaches along with their pros and cons. The review also discusses a variety of key polymers, such as polyaniline, polyacrylonitrile, nylon, polycarbonate, polyethylene terephthalate, polystyrene, polyvinyl alcohol, polyurethane, and cellulose acetate, and their performance and structural properties for a number of applications. The characteristics of functionalized polymer nanofibers, including increased conductivity, adsorption efficiency, biocompatibility, and mechanical stability, make them excellent candidates for use as air and water filtration media, antimicrobial coatings, biosensing applications, tissue engineering, wound healing, drug delivery, smart textiles, and electrochemical energy storage devices. The use of nanofillers, bioactive agents, and hybrid structures is critically reviewed as a means of enhancing the performance and durability of these materials. The review concludes with a discussion on the challenges of scaling up production, reproducibility, sustainability, and long-term functionality and outlines the future opportunities in the area of multifunctional, biodegradable, and commercially viable nanofiber systems.

Mesoporous materials, vital in energy, environmental, and medical applications, require resource-intensive production. Mesoporous vinyl polymers, p-alkyl-N-phenyl-acrylamide (APAA) polymers is introduced, which offer unprecedented advantages in mass production. APAA monomers swiftly form syndiotactic chains through Monomer Aggregation-mediated Rapid, Radical Stereocontrolled (MARRS) polymerization, spontaneously creating mesoporous structures. Structural analyses (X-ray, NMR, DSC, FTIR, TEM, and Brunauer-Emmett-Teller measurements) and molecular mechanics simulations suggest the formation of Y-shaped clusters via intermolecular hydrogen bonding between the syndiotactic chains, which then form either a lamellar or hexagonal cylindrical structure containing mesopores. APAA polymers are highly processable, enabling the straightforward production of microfibers, films, and microparticles. They exhibit significant blue light emission (Quantum Yield: 7-18%) while maintaining exceptional transparency in the visible range. UV-crosslinked APAA polymer fibers, which have both superhydrophobicity and strong water adhesion (petal effect), along with crosslinked APAA polymer microparticles, are highly effective at absorbing liquid-phase volatile organic compounds (VOCs) such as chloroform, tetrahydrofuran, benzene, and toluene. They achieve both rapid absorption (<10 s) and high absorption capacity. Their remarkably simple and economical synthesis, together with their unique physicochemical properties, position APAA polymers as promising, commercially sustainable mesoporous materials with diverse applications such as UV absorbers, transparent blue-emitting films, anti-counterfeiting materials, and water remediation.