Surface Self-Assembly of Functional Electroactive Nanofibers on Textile Yarns as a Facile Approach toward Super Flexible Energy Storage

Textile yarns undergo modifications for use in various smart applications such as energy storage, sensing, and others. For energy storage applications in yarn supercapacitors and batteries, one of the most commonly used yarn modification techniques is the coating of conductive active materials onto textile yarns. The coating process can be via vapor phase polymerization, dip coating, thin film coating using layer by layer assembly, atomic layer depositions, and electrochemical depositions. However, these methods are hectic, uncontrollable, and hardly scalable. Beyond these, they also give brittle coatings which tend to crack easily if coated yarns are incorporated into traditional textiles during use or even during postmanufacturing in weaving/knitting and sewing. Herein, a facile concept for the nanofibers coated on yarn via a modified electrospinning process is proposed to address the challenges. The method is capable of giving all-textile super flexible nanofiber coated yarns with excellent electrochemical performance, exceptional durability, and excellent flexibility, all courtesy of the electroactive and porous nature of the nanofibers coated around textile yarn current collector aiding faster ion diffusion. The method opens up a new scalable strategy to fabricate smart yarns with single nozzle productivity of up to 1.2 m h –1 .