凯发

Graphene fiber (GF) is of practical importance because it integrates the remarkable properties of individual graphene sheets such as high strength, electrical and thermal conductivities into the useful, macroscopic ensembles. GFs possess the common characteristics of fibers like the mechanical flexibility for textiles, while maintaining the uniqueness with advantages over conventional carbon fibers such as low cost, light weight, shapeability and ease of functionalization in an in-situ or post-synthesis fashion. In this regard, we have successfully fabricated the GFs by directly assembling graphene oxide (GO) through a dimension-confined hydrothermal strategy and a large-scale spinning method for functional and shape-controllable perparation of GFs. On the other hand, GFs with in-line assembled graphene sheets present the great potential for development of unconventional fiber-based devices. As demonstrated in our work, GFs can act as the flexible, conductive electrodes for construction of spring-like fiber supercapacitor with highly compressible and stretchable properties, which can also be conveniently woven into the textile for wearable electronics. The hollow GFs with site-specifically modified Pt nanoparticles could behave as a self-powered micromotor agilely moving in aqueous medium. Further, asymmetric G/GO fiber obtained by laser positioning reduction enables the complex, well-controlled motion and deformation in a pre-established manner. Impressively, it can also actuate at one's pleasure and walk as a fiber robot along the channel. Further, we reconstructed the intrinsic configuration of graphenes within the fiber body and achieved a new type of moisture-driven rotational motor by rationally designing the rotary processing of the freshly spun GO fiber hydrogel. Remarkably, the twisted GO fiber (TGF) with rearranged graphene sheets within the fibers presents superb performance as a reversible rotary motor with a rotary speed of up to 5190 revolutions per minute and a tensile expansion of 4.7% under humidity alternation. This moisture-responsive actuation behavior of TGF also builds the basis for development of humidity switches and the promising moisture-triggered electric generators.