Tension-induced toughening and conductivity enhancement in sequentially bridged MXene fibers

Abstract

Ti3C2Tx MXene is a promising active material for developing fiber-based devices due to its exceptional electrical conductivity and electrochemical capacitance. However, fabricating robust fibers with high MXene content remains challenging due to shortcomings such as low interfacial adhesion between sheets and shrinkage-induced sheet disorientation during processing, leading to diminished physical and electrochemical properties. Here, we demonstrate the fabrication of tough, conductive, and electrochemically active fibers through a sequential bridging (SB) strategy involving calcium cation (Ca2+) infiltration of cellulose nanocrystal (CNC)-bridged MXene, cross-linked and dried under tension. The resulting fibers exhibited a record toughness of ~2.05 MJ m-3 and retained high volumetric capacitance (~985 F cm-3), attributed to the synergistic CNC bridging, Ca2+ cross-linking, and tension application during fiber drying. These fibers also surpass the conductivity of their unaligned pristine MXene counterpart (~8,347 S cm–1 vs. ~5,078 S cm-1), ascribed to the tension-induced improvement in MXene alignment within these fibers, mitigating the undesirable effects of inserting an insulating CNC bridge. We anticipate that improving the toughness and conductivity of sequentially bridged MXene (SBM) fibres will pave the way for the production of robust multifunctional MXene fibres, allowing their use in practical high-performance applications like wearable electronics and energy storage devices.

Robust Biocompatible Fibers from Silk Fibroin Coated MXene Sheets

“…[14] This approach, as well as the optimization of other spinning parameters such as shear rate, coagulation bath composition, and drying conditions to further improve fiber morphology may be explored in future studies. [28,35,46]…”

Recent Advances in MXene-Based Fibers, Yarns, and Fabrics for Wearable Energy Storage Devices Applications

“…The tensile strength of wet-spun CNTs/MXene-TPU fibers is only 12 MPa, while that of MXene (95 wt %)/CNC fibers is as high as 156 MPa. The high tensile strength of MXene/CNC fiber is attributed to the combined effect of synergistic CNC bridging, calcium ion, Ca 2+ , cross-linking, and tension applied during drying . MXene and rGO are also widely studied composite materials in wet spinning.…”

“…The high tensile strength of MXene/CNC fiber is attributed to the combined effect of synergistic CNC bridging, calcium ion, Ca 2+ , crosslinking, and tension applied during drying. 117 MXene and rGO are also widely studied composite materials in wet spinning. MXene/rGO-based fibers are prepared by wet spinning using the synergistic effect between MXene and rGO.…”

“…Compared with pure MXene material, the mixture of MXene and other materials is easier to be spun into fibers by wet spinning, and the miscibility of solvent to MXene and other materials should be considered. , Wet spinning of other materials mixed with MXene can improve the wet-spinning processing performance of MXene flakes, including graphene oxide, poly­(vinyl alcohol) (PVA), PEDOT:PSS, , PAN, reduced graphene oxide (rGO), − cellulose nanocrystals (CNC), carbon nanotubes (CNT), , thermoplastic polyurethane (TPU), etc. The advantage of wet spinning with other materials is that it can reduce the accumulation of MXene sheets in the wet spinning process and improve the arrangement and morphological accumulation of MXene sheets and polymers along the fiber axis .…”

Applications of X‐Ray‐Based Characterization in MXene Research

“…[41][42][43] In this review, we provide an overview of different stateof-art X-ray methods and how these have advanced MXene research. We introduce the fundamental principles and approaches developed for qualitative and quantitative characterization of MXenes using widely utilized X-ray-based techniques, including XRD, [19,22,44] SAXS/WAXS, [15,30,31,33,45] X-ray photoelectron spectroscopy (XPS), [42,46,47] X-ray absorption spectroscopy (XAS), [48][49][50] and X-ray imaging (micro-computed tomography or micro-CT). [51] Our discussions focus on the key information provided via each technique, with emphasis on how they contribute to the fundamental understanding and development of MXenes toward an array of applications.…”