MXene Composite and Coaxial Fibers with High Stretchability and Conductivity for Wearable Strain Sensing Textiles

Abstract

The integration of nanomaterials with high conductivity into stretchable polymer fibers can achieve novel functionalities such as sensing physical deformations. With a metallic conductivity that exceeds other solution‐processed nanomaterials, 2D titanium carbide MXene is an attractive material to produce conducting and stretchable fibers. Here, a scalable wet‐spinning technique is used to produce Ti3C2Tx MXene/polyurethane (PU) composite fibers that show both conductivity and high stretchability. The conductivity at a very low percolation threshold of ≈1 wt% is demonstrated, which is lower than the previously reported values for MXene‐based polymer composites. When used as a strain sensor, the MXene/PU composite fibers show a high gauge factor of ≈12900 (≈238 at 50% strain) and a large sensing strain of ≈152%. The cyclic strain sensing performance is further improved by producing fibers with MXene/PU sheath and pure PU core using a coaxial wet‐spinning process. Using a commercial‐scale knitting machine, MXene/PU fibers are knitted into a one‐piece elbow sleeve, which can track various movements of the wearer's elbow. This study establishes fundamental insights into the behavior of MXene in elastomeric composites and presents strategies to achieve MXene‐based fibers and textiles with strain sensing properties suitable for applications in health, sports, and entertainment.

MXene‐Based Fibers, Yarns, and Fabrics for Wearable Energy Storage Devices

“…[35,48] However, in terms of electrical conductivity, it has been shown that MXene films prepared from aqueous dispersions have significantly higher conductivity than those prepared from DMF and DMSO. [41] Depending on the application, the solvent should be carefully selected with stability and electronic properties in mind. From the results of these works, we have a "library" of polar organic solvents to choose from that can disperse MXene, opening new avenues to develop a wide range of MXene composite dispersions for fiber spinning and other processing methods.…”

“…Due to the good dispersibility of MXene in polar solvents, a large range of materials, e.g., PCL, [36] polyurethane (PU), [41] PEDOT:PSS ( Figure 3c-ii,iii), [99] and GO, [111,112] have been added as components to the spinning dope to produce MXene-based composite fibers. These spinnable materials significantly improved the processability of MXene flakes into fibers.…”

“…Prompted by these properties, several studies have been dedicated to developing MXene-based fibers since their first demonstration in 2017, [37] spanning applications from wearable energy storage [37,38] to heated textiles, [39] pressure sensors, [40] and strain sensors. [41] For energy storage applications, TSCs made from MXene-based fibers, yarns, and fabrics have demon strated record capacitances compared to devices made from other materials, including graphene, carbon nanotubes (CNTs), and conducting polymers. [42][43][44] These fibers and Ariana Levitt is a PhD candidate and NSF-GRFP fellow pursuing a degree in Materials Science and Engineering at Drexel University, under the mentorship of Prof. Yury Gogotsi and Prof. Genevieve Dion.…”

MXene-based Sensors for Detecting Human Physiological Information

“…MXenes were discovered in 2011 by Gogotsi and coworkers. (2,3,(6)(7)(8)(9)(10) MXenes are typically synthesized from the parent MAX phases (M n+1 AX n with early transition metals (group 13-16 elements), carbon, and nitrogen, with n = 1-4) by strong acid etching the layer obtained by intercalation-assisted delamination. MXene (M n+1 X n T x ) flakes with a high aspect ratio (up to ≈106) and abundant terminating functional groups (T x ) are desirable for producing polymer composites with novel functionalities.…”

“…MXene (M n+1 X n T x ) flakes with a high aspect ratio (up to ≈106) and abundant terminating functional groups (T x ) are desirable for producing polymer composites with novel functionalities. (9) More than 60 distinct types of pure MAX phases and 20 types of MXenes have been discovered. (11) MXenes have been employed in energy storage, (1,(10)(11)(12)(13)(14)(15)(16)(17) catalysis, (3,(10)(11)(12)16) supercapacitors, (10,13,17,18) Li-ion batteries, (10,13,14,19) electronic devices, (1,20) sensing, (2,(11)(12)(13)(15)(16)(17)(20)(21)(22) biomedical applications, (10,14,15,19,(23)(24)(25) and environmental remediation.…”