Wenxin Cao,Lei Yang,Xiaodong Qi,Ying Hou,Jiaqi Zhu,Ming Yang
Coaxial fibers are the key elements in many optical, electrical, and biomedical applications. Recent success in materials synthesis has provided versatile choices for the core part, but the search of high-performance sheath materials remains much less productive. These surface coatings are however as important as the core for their role as protection layers and interaction medium with the externals, thereby critically affecting the real performance of coaxial fibers. Here it is shown that aramid nanofibers (ANFs) with exceptional environmental stability and mechanical properties can be advanced coating materials for both wet- and dry-spun carbon nanotube (CNT) wires. Co-wet-spinning ANFs with CNT aqueous dispersion can produce coaxial fibers with a compact sheath comprised of aligned ANFs, showing much enhanced mechanical properties by transferring stress to the sheath without sacrificing the conductivity. On the other hand, an immersion-precipitation process is used to prepare a porous sheath made from randomly distributed nanofibers on dry-spun CNT wires, which can be combined with ionic conductive gel electrolyte as a strong packaging layer for flexible solid-state supercapacitors. The excellent intrinsic characteristics as well as variable ways of structural organizations make ANF-based coatings an attractive tool for the design of multifunctional high-performance hybrid materials.
Light-responsive liquid crystal elastomer (LCE) fibers hold considerable promise for use in the development of soft robotics and smart devices due to their flexibility and controllability. However, most of the inorganic materials with photothermal effects are incompatible with the liquid crystal elastomer matrix, which can result in unstable interfacial bonding between the inorganic materials and the organic liquid crystal system. Meanwhile, the multidimensional space deformation of liquid crystal elastomer fibers remains challenging. Here, numerous polymerizable graphene oxide (GO) monomers are employed as a photothermite, and the GO@LCE fiber actuators with stable organic-inorganic interfacial bonding are constructed by dry spinning and two-step crosslinking method. The actuators demonstrate remarkable photothermal conversion capability, and they also exhibit exceptional breaking strength, reusability and work capacity (400.7 kJ m −3 ), benefiting from the covalent bonding between the interfaces. As a proof-of-concept, light-controlled artificial muscle and micro crawler based on the one-dimensional linear motion of GO@LCE fiber actuators are successfully constructed. Importantly, GO@LCE knitted fabrics, which are capable of three-dimensional bending deformations in different degrees and forms, are skillfully woven through the design of knitted structures. This work can enhance new possibilities for the advancement of soft robotics and smart textiles.
危险品化学品经营许可证（带存储）