In-plane molecular cord bridging as a method for boosting MXene fiber strength and toughness

Huihui Wang; Jianfeng Gu; Chao Li; Donghui Li; Weiqing Zhan; Xinmin Zhang; Xinyi Ji; Yongsheng Chen; Jiajie Liang

doi:10.1038/s41467-026-76585-2

. 2026 Aug 11;17:9637. doi: 10.1038/s41467-026-76585-2

In-plane molecular cord bridging as a method for boosting MXene fiber strength and toughness

Huihui Wang ^1,^#, Jianfeng Gu ^2,^#, Chao Li ¹, Donghui Li ¹, Weiqing Zhan ¹, Xinmin Zhang ¹, Xinyi Ji ¹, Yongsheng Chen ³, Jiajie Liang ^1,^3,^4,^✉

PMCID: PMC13554133 PMID: 42711304

Abstract

MXenes enable high-performance fibers with strength, toughness, and conductivity, yet weak edge-to-edge interactions between nanosheets remain a critical challenge. Inspired by the cord-bound architecture of lamellar armor, we use molecular cords of carboxymethyl cellulose-wrapped single-walled carbon nanotubes to bridge adjacent MXene nanosheets via ionic coordination. Through mild and continuous wet-spinning, crosslinking, and hot-pressing, we fabricate MXene fibers containing only 0.12 wt% of the molecular cords that deliver enhanced mechanical properties: a tensile strength of 1.48 ± 0.06 GPa (peak: 1.55 GPa), ductility of 17.7 ± 0.8%, and toughness of 131.0 ± 8.7 MJ m⁻³ (peak: 140 MJ m⁻³), representing enhancements of 480%, 300%, and 1620% over pristine MXene fibers, while retaining electrical conductivity above 10,400 S cm⁻¹ and a volumetric capacitance of 1645 F cm⁻³. These molecular cords reinforce interlayer bonding and in-plane bridges, enabling efficient stress transfer and crack inhibition in 2D nanosheet fibers. This molecular cord strategy could potentially be applied to maximize the mechanical performance of fibers derived from other two-dimensional nanosheets.

Subject terms: Materials science, Nanoscience and technology

Inspired by laced lamellar armor, a molecular cord strategy was developed to strengthen edge-to-edge coupling between MXene nanosheets, producing fibers that combine high strength and toughness with high tensile strength and electrical conductivity.

Introduction

The concurrent integration of high strength, toughness, and electrical conductivity into a single synthetic fiber represents a foundational breakthrough in materials science^1–4. Realizing such a fibrous material would unlock transformative technologies, from next-generation wearable electronics and smart textiles to lightweight aerospace cabling and multifunctional composites for advanced robotics and energy storage^5–8. While carbon nanomaterial-based fibers (CNFs, e.g., graphene and carbon nanotube (CNT) fibers) exhibit exceptional tensile strength—often in the gigapascal range—their widespread application is hindered by intrinsic brittleness (typically <5% fracture strain), limited electrical conductivity (often below 3000 S cm⁻¹), and reliance on harsh fabrication conditions (i.e., ultrahigh-temperature process) (Supplementary Table 2)^9–11. As an emerging two-dimensional nanomaterial, titanium carbide (Ti₃C₂T_x) MXene possesses a compelling combination of properties—including high mechanical strength, exceptional electrical conductivity, and innate hydrophilicity—that enables the scalable fabrication of highly conductive MXene fibers (>8000 S cm⁻¹) through ambient wet-spinning^1,2,12. Nevertheless, current MXene fibers suffer from inadequate mechanical performance, with brittle feature and tensile strengths generally below 300 MPa (Supplementary Table 1)^13–15. To date, the creation of a macroscopic fiber that simultaneously delivers high strength, toughness, and electrical conductivity remains a central challenge in advanced fiber science.

Beyond universal structural challenges in one-and two-dimensional nanomaterial fibers, such as alignment and compactness^1,16,17, the mechanical inferiority of MXene fibers relative to CNFs stems from two fundamental issues: weak interlayer interactions^12,18 and, more critically, insufficient in-plane edge-to-edge coupling between MXene nanosheets (Fig. 1a)^19,20. While graphene layers develop strong π–π stacking^21,22, MXene nanosheets rely solely on weak van der Waals forces and hydrogen bonding in their stacks^1,2. Significant efforts thus have focused on enhancing interlayer interactions through interfacial modification in MXene fibers^2,12,23–25. For instance, our group achieved a mechanical strength of 1 GPa in MXene fibers via strategic interface design and internal micropore regulation²⁶. However, even with optimized interlayer bonding, MXene fibers still trail far behind CNFs in mechanical strength. This persistent gap reveals an overlooked yet decisive factor: poor in-plane edge-to-edge connectivity between MXene nanosheets. The greater thickness of MXene (~1.8 nm compared to graphene’s ~0.34 nm) results in significantly enhanced stress concentration at in-plane inter-sheet junctions^19,20,27,28. Under tension, weak edge-to-edge interactions promote inter-sheet slippage and separation, leading to crack initiation and ultimate MXene fiber breakage (Fig. 1a, b). Consequently, the weak in-plane interactions between MXene nanosheets impose a critical constraint on mechanical performance improvement of MXene fibers. However, few works focused on directly resolving the intrinsic weakness of in-plane edge-to-edge junctions in MXene assemblies.

Employing large-sized MXenes could be a viable way to improve the issue of in-plane inter-sheet connectivity^13,29. However, large-sized MXenes would inevitably induce more voids in MXene fibers during the fiber fabrication process, which reduced fibers’ compactness and impaired their mechanical performance^17,29. An alternative approach involves chemical crosslinking MXenes through their edges to establish strong inter-sheet bridges^1,20. While this chemical bridging strategy enhances structural integrity, it concurrently constrains inter-sheet sliding capability, resulting in diminished fracture strain and ultimately compromising the fibers’ toughness²⁰. Moreover, inherent charge dichotomy of MXene nanosheets (negatively charged surface and positively charged edge) creates fundamental design constraints for interfacial modifiers, as few molecular systems can enhance interactions with both charge domains^30,31. Thus, establishing robust in-plane inter-sheet bridges in MXene nanosheets persists as a critical challenge.

Ancient laced lamellar armor systems employed cord linkages to interconnect individual armor plates (Fig. 1c)³². This design offers two key mechanical advantages over solid plate armor: (i) the strong, tough cord bridges enable effective impact energy transfer and dissipation, and (ii) the compliant cord knots allow controlled plate rotation, improving overall flexibility and toughness. This historical engineering paradigm provides valuable inspiration for addressing the current challenge of bridging in-plane MXene nanosheets in their fibers.

Here, we propose a continuous, long-range in-plane bridging strategy to directly resolve the weak edge-to-edge connectivity between MXene nanosheets. We introduce a molecular cord—carboxymethyl cellulose (CMC)-wrapped single-walled carbon nanotubes (SWCNTs, CMC-SWCNTs abbreviated as CS)—in conjunction with metal ions to bridge MXene nanosheets, both in-plane and across stacked layers, within the fiber architecture. This strategy produces a CS-bridged MXene (CS-MXene) fiber that simultaneously exhibits superior mechanical strength, ductility, and toughness, while retaining high electrical conductivity. The CS works as molecular cord within CS-MXene fiber through three synergistic mechanisms (Fig. 1d, e): (i) CMC can function not only as a dispersant and interfacial regulation unit for SWCNTs, but also enables the formation of strong ionic bonding interactions between SWCNTs and MXene, (ii) micrometer-long CS bridges multiple in-plane MXene nanosheets, forming a load-bearing armor lamellae-like architecture that prevents crack formation and propagation, and (iii) the slidable yet robust MXene/CS interfaces facilitate energy-dissipative interlayer slippage, simultaneously enabling efficient three-dimensional stress transfer—both vertically across MXene stacks and horizontally between in-plane nanosheets—to the strong SWCNTs. Remarkably, incorporating just 0.12 wt% CS yields CS-MXene fibers with exceptional mechanical properties that set new benchmarks for MXene-based fibers (Supplementary Fig. 11). The wet-spun CS-MXene fibers achieve a tensile strength of 1.55 GPa and unprecedented toughness of 140 MJ m⁻³, values that far surpass all previously reported MXene-based fibers (Fig. 1f and Supplementary Table 1)^2,33,34. With tensile strength exceeding 1.5 GPa, our CS-MXene fibers outperform most graphene- and CNT-based fibers in combined mechanical toughness and electrical conductivity (Fig. 1g and Supplementary Table 2)^10,35–37. This unusual combination of high strength and high toughness makes them particularly attractive for advanced applications in wearable fiber-shaped electronics, structural composites, and energy-storage devices. For example, the CS-MXene fibers demonstrate exceptional electrochemical characteristics, including an ultrahigh volumetric capacitance of 1645 F cm⁻³ at 5 mV s⁻¹, while maintaining mechanical strength significantly superior to that of previously reported MXene-based fiber electrodes (Fig. 1h and Supplementary Table 3)^38–40.

Results and discussion

Design and fabrication of CS-MXene fibers

The laced lamellar armor relies critically on the mechanical properties of its bridging cords, which fulfill three essential criteria: (i) high strength and modulus to prevent failure under dynamic loading, (ii) high toughness and durability to bear and dissipate impact energy, and (iii) strong knot strength to ensure armor’s structural integrity under tension (Fig. 1c). Inspired by these, we selected SWCNTs as molecular cords for MXene bridging (Fig. 1c, d), owing to their exceptional mechanical strength, Young’s modulus, toughness, durability, and electrical conductivity^9,41,42. However, SWCNTs present two intrinsic limitations: (i) strong van der Waals-driven aggregation into bundles, and (ii) poor interfacial interaction with hydrophilic MXene surface due to their hydrophobic nature⁴³. To address these issues, we utilized CS (obtained from OCSiAl) composed of CMC-wrapped SWCNTs as the molecular cords. CMC can debundle and stabilize SWCNTs in aqueous dispersion via associative interactions (Supplementary Fig. 1)^44–46, while simultaneously forming strong interfacial bonds with the terminal groups of MXene nanosheets^18,47. This results in strong yet dynamic molecular knots that mimic the interlocking cord knots in lamellar armor (Fig. 1c–e). High-resolution transmission electron microscope (HRTEM) images demonstrate that flexible CS molecular cords can be uniformly dispersed in water, with diameter of ~10 nm and length ~5 μm (Supplementary Fig. 2).

To fabricate the CS-MXene fibers, we first mixed MXene nanosheets (lateral size ~1.9 μm, thickness ~1.8 nm with a Zeta potential of 30.84 mV, Supplementary Fig. 3) with CS to prepare a liquid crystal colloidal dispersion at a solid concentration over 220 mg mL⁻¹ (Supplementary Fig. 4). Notably, the incorporation of merely 0.12 wt% CS increased the dispersion viscosity by 40% versus MXene-only controls (Supplementary Fig. 5), evidencing strong interfacial interactions between CS and MXene. The highly concentrated colloidal dispersion was then continuously and stably wet-spun into macroscopic fibers (Supplementary Fig. 6 and Supplementary Movie 1), followed by soaking in a MgSO₄/methanol bath to form ionic coordination bonds between MXene and CMC to bridge in-plane and stacked MXene nanosheets (Fig. 1d)^12,18. The wet-spun and CS-MXene fiber was subsequently passed through a hot-press setup under pressure of 11 kPa and 70 °C to regulate its compactness and porosity (“Methods”, Supplementary Fig. 7 and Fig. 13)²⁶, followed by drying to yield the final CS-MXene fibers. According to our previous study, the synergistic effect of optimized porosity and interfacial interactions can enhance the strength and toughness of MXene fibers²⁶. Through systematic optimization, the CS loading was determined to be optimal at 0.12 wt% (discussed below). Control samples, including neat MXene fibers and MXene fibers intercalated by CMC (C-MXene fiber, 0.12 wt% CMC), were fabricated under identical conditions to isolate the bridging effect from SWCNTs. The neat MXene, C-MXene, and CS-MXene fibers have similar diameters (~60 μm). The porosity of C-MXene fibers (21%) is marginally lower than that of neat MXene fibers (22%), and CS-MXene fibers exhibit a further slight reduction in porosity (20%; Supplementary Fig. 8). This may be due to CMC acting as a flexible polymer binder that fills the interlayer voids of MXene nanosheets, resulting in a denser fiber structure; while the intercalation and bridging effects of SWCNTs further compact the internal packing, leading to a slight reduction in porosity (Supplementary Note 4)^25,48. Moreover, the degree of nanosheet alignment (orientation factor) of C-MXene fibers decreases slightly, which may be attributed to the steric hindrance and chain entanglement effects of the CMC macromolecular chains, disrupting the orientational order of the MXene sheets (Supplementary Fig. 4 and Figs. 9 and 10)⁴⁹. In contrast, leveraging the alignment-guiding and spatial-confinement capabilities of one-dimensional SWCNTs, the CS-MXene fibers recover a high degree of orientation comparable to that of neat MXene fibers (Supplementary Fig. 9)^50,51. This enhanced orientation, in turn, could contribute to the improved mechanical strength of the MXene-based fibers⁴⁸.

Characterization of CS-bridged MXene nanosheets

The CS-MXene nanosheets were initially characterized by HRTEM, atomic force microscope (AFM), and scanning electron microscopy (SEM). As shown in Fig. 2a–c, micrometer-long, flexible CS acted as molecular cords, bridging both in-plane and stacked MXene nanosheets. SEM images of the liquid nitrogen-fractured cross-sections revealed an ordered layered and microporous structure in neat MXene, C-MXene, and CS-MXene fibers (Fig. 2d and Supplementary Fig. 11). Notably, different from neat MXene and C-MXene fibers, the CS-MXene fibers exhibited uniformly distributed CS intercalated between MXene interlayers, with partial pull-out clearly observed (Fig. 2e). CMC segments wrapping around SWCNTs were visible within the pulled-out CS regions (Fig. 2f). Additionally, CS molecular cords can be found spanning across the surfaces of MXene nanosheets, forming in-plane connections (Fig. 2f).

Fig. 2 — a HRTEM and b AFM images showing CS-bridged multiple MXene nanosheets. c Height profiles for CS-bridged MXene nanosheets in (b) along blue line and green line. d–f SEM images of the liquid nitrogen-fractured cross-section for CS-MXene fibers. g XPS spectrum of CS-MXene fibers before and after crosslinking in MgSO₄/methanol bath in C 1s region. h Comparisons of FT-IR spectra for pure MXene fiber and CS-MXene fiber before and after crosslinking in MgSO₄/methanol bath. i 2D-COS synchronous spectrum of MXene-based fibers, obtained from the corresponding one-dimensional FT-IR spectra in (h). The color scale represents two-dimensional infrared signal intensity in arbitrary units. Source data are provided as a Source Data file. Each experiment in (a, b, and d–f) was repeated three times independently with similar results.

The carboxyl (–COOH) groups of CMC in CS and the terminal (Ti-OH) groups of MXene exhibit strong coordination bonding with Mg²⁺, with calculated binding energies of −2.79 eV (COOH→Mg²⁺) and −3.83 eV (Ti-OH→Mg²⁺), respectively (Supplementary Fig. 12). X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared (FTIR) spectroscopy confirm the formation of these coordination bonds. The survey spectra before and after Mg²⁺ crosslinking and high-resolution Mg 1s spectra of the fibers confirm the successful incorporation of Mg²⁺ (Supplementary Fig. 13). In the C 1s XPS spectra, the C-Ti-Tₓ peak of MXene shifted from 283.05 eV in pristine MXene fibers to higher binding energies by 0.33 and 0.78 eV in CS-MXene fibers before and after Mg²⁺ crosslinking, respectively (Fig. 2g)^12,52. The C-Ti-O peak exhibits the same trend in the XPS O 1s and Ti 2p spectra (Supplementary Fig. 14). Similarly, as shown in Fig. 2h, FTIR spectra revealed a progressive redshift in the Ti-OH stretching vibration from 3434.6 cm⁻¹ (neat MXene fibers) to 3432.2 and 3425.4 cm⁻¹ in CS-MXene fibers before and after crosslinking^12,53. The –COO⁻ peak of CMC also shifted from 1620.4 to 1618.4 cm⁻¹ upon Mg²⁺ coordination⁵⁴. Further evidence came from 2D synchronous FTIR spectra in the range of 1500–3600 cm⁻¹ (Fig. 2i), which displayed strong autopeaks at 3425 cm⁻¹ (Ti-OH) and 1618 cm⁻¹ (–COO⁻), highlighting the pronounced sensitivity of these groups to Mg²⁺ binding⁵⁵. Collectively, these results demonstrate the critical role of Mg²⁺-mediated coordination in forming robust links between CS and MXene nanosheets. These strong but dynamic crosslinks work as cord knots of laced lamellar armor to bridge MXene nanosheets in their fibers.

Mechanical properties of CS-MXene fibers

Fig. 3a, Supplementary Figs. 15–17, and Supplementary Tables 4–6 exhibited the tensile stress-strain curves of neat MXene fibers, C-MXene fibers, and CS-MXene fibers with different CS contents. Tensile testing demonstrated remarkable mechanical enhancement in CS-MXene fibers compared to both neat MXene and C-MXene fibers. At a minimal CS loading of 0.08 wt%, the CS-MXene fibers achieved simultaneous gigapascal-scale strength and exceptional toughness (>100 MJ m⁻³). Optimal performance emerged at 0.12 wt% CS, with the fibers exhibiting a tensile strength of 1.48 ± 0.06 GPa (peak: 1.55 GPa), an extensibility reaching 17.7 ± 0.8% strain, and a toughness of 131.0 ± 8.7 MJ m⁻³ (peak: 140 MJ m⁻³). These values represented substantial improvements over reference fibers: 4.8×, 3.0×, and 16.2× enhancements versus neat MXene fibers, and 1.2×, 0.8×, and 2.2× increases relative to C-MXene fibers, respectively (Fig. 3b). While higher CS loading (0.16 wt%) induced marginal property reduction in CS-MXene fibers—potentially due to CS aggregation creating stress concentrators—the mechanical performance remains superior to both control groups (Supplementary Fig. 4 and Fig. 18). Moreover, the high toughness and flexibility allowed the CS-MXene fibers to be folded and tightly knotted without breaking or cracking (Supplementary Fig. 19), making them suitable for weaving into electronic textiles (Supplementary Fig. 20).

Notably, the CS-MXene fibers maintained outstanding electrical conductivity (>10,000 S cm⁻¹) at both 0.08 and 0.12 wt% CS loadings, benefiting from SWCNTs’ intrinsic conductivity and bridging effects (Fig. 3c). The CS-MXene fibers with 0.12 wt% CS achieved peak conductivity of 10,400 ± 870 S cm⁻¹, matching neat MXene fibers while surpassing C-MXene analogs (Fig. 3b and Supplementary Fig. 21). What distinguished the advance of our CS-MXene fibers is their mild, solution-processable fabrication process, combined with low-temperature (~70 °C) hot-pressing post-treatment to achieve structural optimization and stabilization (Supplementary Figs. 22 and 23), which enables superior mechanical and electrical performance without the extreme processing conditions—such as treatments exceeding 1000 °C—typically required for high-performance graphene- or CNT-based fibers^27,56,57. This breakthrough establishes a practical and scalable pathway to producing fibers that simultaneously excel in strength, toughness, and conductivity—a critical step toward real-world applications.

Moreover, the CS-MXene fibers exhibit dramatically improved resistance to stress relaxation compared to control analogs (Fig. 3d). Specifically, while neat MXene and C-MXene fibers retained only 55.7 and 60.4% of their initial stress at 0–3% strain after 7200 s and 11,000 s, respectively, CS-MXene fibers maintained over 78% stress retention even after 25,000 s. Notably, under high strain of 12–15%, CS-MXene fibers still preserved 63% of their stress after 30,000 s (Supplementary Fig. 24). In addition, CS-MXene fibers exhibit excellent thermal stability, maintaining consistent tensile strength, toughness and stress-strain behavior under varying temperatures (Supplementary Fig. 25). The increase in conductivity with rising temperature can be attributed to the negative temperature coefficient behavior of the multilayered MXene composite⁵⁸. This exceptional stability originated from the robust coordination bonds between CS and MXene nanosheets, which effectively suppress in-plane nanosheet slippage and separation during prolonged dynamic loading.

The CS-MXene fibers also demonstrate unprecedented fatigue resistance, outperforming both neat MXene and C-MXene fibers by a substantial margin (Fig. 3e). The CS bridges between adjacent MXene nanosheets not only enhanced load transfer but also impeded crack propagation under cyclic deformation. At a stress ratio of 0.92, neat MXene and C-MXene fibers sustained only ~4,000 cycles within 174–194 MPa and ~7000 cycles within 480–515 MPa, respectively (Fig. 3e). In contrast, CS-MXene fibers could withstand over 20,000 cycles within an ultrahigh stress range of 1120–1195 MPa, highlighting the efficient bridging effect from CS for deconcentrating stress. Our CS-MXene fibers also maintain exceptional electrical stability under repetitive strain. After 50,000 stretching cycles at strain of 12–15%, their electrical resistance exhibited a slight decrease rather than the expected increase (Fig. 3f), suggesting structural reconfiguration or better MXene alignment that enhances charge transport pathways^12,18. This is evidenced by the higher orientation factor of the fibers after stretching cycles (Supplementary Fig. 26). This combination of mechanical durability and electrical reliability under dynamic loading is rarely seen in existing MXene fibers or other CNFs^2,4,59.

Strengthening and toughening mechanism

We explore the mechanisms for the increase in the tensile strength and toughness of the CS-MXene fibers. In neat MXene fibers, stress concentration at in-plane nanosheet edges induces interlayer slippage and microcrack propagation along weak inter-sheet interfaces, resulting in characteristic brittle fracture (Fig. 1a). C-MXene fibers demonstrate transitional behavior where strong ionic coordination bonds enhance interfacial load transfer while maintaining controlled interlayer slippage through CMC polymer chain stretching. Nevertheless, C-MXene fibers remain fundamentally constrained by insufficient in-plane coupling strength, as localized stress-induced CMC rupture ultimately triggers crack initiation and propagation (Fig. 4a). In comparison, the CS-bridged system achieves multiscale reinforcement through three synergistic mechanisms: (i) strong coordination bonding at interfaces creates robust stress transfer pathways; (ii) high-aspect-ratio SWCNTs bridge and mechanically interlock adjacent MXene layers, suppressing crack initiation; and (iii) the compliant yet durable CS facilitates additional energy dissipation. Most critically, when localized stresses exceed critical levels, the highly strong SWCNTs actively bridge developing microcracks, transforming what would be catastrophic fracture in neat MXene fibers into distributed, energy-absorbing modes.

Fig. 4 — a Structural models illustrating the fracturing process of C-MXene fibers and CS-MXene fibers under tension. b MD simulation snapshots and shear strain distribution of C-MXene fibers and CS-MXene fibers. SEM images of the tensile-fractured cross-sections for c neat MXene fibers, d C-MXene fibers, and (e–g) CS-MXene fibers. Source data are provided as a Source Data file. Each experiment in (c–g) was repeated three times independently with similar results.

To further verify the bridging effect of CS on the mechanical behavior of CS-MXene fibers, we conduct molecular dynamics (MD) simulations to analyze representative snapshots and atomic strain distributions, which elucidate the shear strain dissipation mechanisms of neat MXene, C-MXene, and CS-MXene fibers at the molecular level (Supplementary Figs. 27–29)^60,61. The MD simulations demonstrate that in CS-MXene fibers, CS plays a crucial role in dissipating shear strains while SWCNTs primarily bear the shear stress under large tension, facilitating efficient load transfer between adjacent MXene nanosheets both in-plane and interlayer (Fig. 4b and Supplementary Fig. 27). This thereby suppresses crack initiation and propagation. In contrast, highly localized shear strain is concentrated on MXene nanosheets in C-MXene and neat MXene fibers under tensile deformation (Fig. 4b and Supplementary Figs. 28 and 29). This strain localization ultimately leads to in-plane MXene nanosheet slippage, separation, and crack formation due to the weak in-plane connection between MXenes (Supplementary Movies 2–4).

The SEM images of the tensile-fractured fiber cross-sections further reveal that the CS-bridging effect acting as a strengthening and toughening mechanism. As shown in Fig. 4c, d, the C-MXene fibers exhibit slight curling of nanosheet edges at the fracture surface, a feature absent in neat MXene fibers, which indicates stronger interfacial interactions in the C-MXene fibers than in neat MXene fibers. Remarkably, in contrast to the brittle fracture behavior observed in neat MXene and C-MXene fibers, CS-MXene fibers display distinct ductile fracture characteristics featuring highly rugged fracture surfaces with significant roughness, pronounced curvature and irregularity of MXene nanosheet edges, torn MXene nanosheets and fractured CS, along with pull-out of long CS cords (Fig. 4e–g). These morphological features reveal multiscale energy dissipation mechanisms enabled by robust interlayer bonding and in-plane bridging via CS, which collectively account for the exceptional mechanical performance of CS-MXene fibers. The combined MD simulations and SEM characterizations provide compelling evidence that CS acts as both a molecular-scale strain redistributor and toughening agent through its unique bridging effect.

Robust multifunctional performance

We further demonstrate the exceptional mechanical and electrical properties of the CS-MXene fibers by suspending and wiring a 10 W light-emitting diode (LED). As demonstrated in Fig. 5a, two 3 cm-long CS-MXene fibers (diameter ~60 μm) supported a custom 106 g LED—over 402,100 times fibers’ own mass—while enduring tensile stresses exceeding 1 GPa and simultaneously carrying an ultrahigh current density of 125.7 A cm⁻² to illuminate the LED. Beyond electromechanical resilience, the CS-MXene fibers exhibit outstanding electrochemical performance. They achieve a volumetric capacitance of 1645 F cm⁻³ at 5 mV s⁻¹ (Fig. 5b and Supplementary Fig. 30), retaining 45% capacity even at high scan rate of 300 mV s⁻¹ (Fig. 5c), which surpass the neat MXene fibers and most reported MXene-based fiber electrodes (Supplementary Table 3)^36–38. Cycling stability for CS-MXene fiber electrodes is also remarkable, with 92% capacitance retention after 10,000 cycles at 20 A cm⁻³ (Fig. 5d).

Fig. 5 — a A 106 g LED lit and suspended by two CS-MXene fibers. b Cyclic voltammetry curves of neat MXene fibers and CS-MXene fibers at 5 mV s⁻¹ in a three-electrode system using a 1.0 M H₂SO₄ electrolyte. c The volumetric capacity of neat MXene fibers and CS-MXene fibers at various scan rates. d The stability of CS-MXene fibers during 10,000 cycles at 20 A cm⁻³, and the inset shows the galvanostatic charge-discharge curves for the fiber electrode at specific charge-discharge cycle. Source data are provided as a Source Data file.

We overcome a persistent challenge in harnessing the mechanical potential of MXenes to create synthetic fibers that integrate ultrahigh strength, toughness, and electrical conductivity. In contrast to conventional methods that focus primarily on interfacial reinforcement or enhanced alignment, we introduce a molecular cord strategy employing CS to form robust crosslinks between MXene nanosheets, effectively bridging in–plane and interlayer gaps. This design facilitates efficient stress transfer—both vertically across MXene stacks and horizontally along the basal planes—effectively converting CS molecular cords into a dynamic strain–redistributing and energy–dissipating components that impedes crack initiation and propagation while under load. The resulting wet-spun CS-MXene fibers exhibit unprecedented mechanical properties, including a tensile strength of 1.48 ± 0.06 GPa, ductility of 17.7 ± 0.8%, and toughness of 131.0 ± 8.7 MJ m⁻³. Furthermore, they exhibit outstanding fatigue resistance, enduring >20,000 cycles at ultrahigh stresses of 1120–1195 MPa, and retain high electrical conductivity (>10,400 S cm⁻¹) even after 50,000 stretching cycles at 12–15% strain, in addition to achieving high volumetric capacitance. Our work establishes the in-plane molecular cord bridging mechanism as a versatile and scalable platform for transforming a broad range of two-dimensional nanomaterials into high-performance, multifunctional fibers suited for advanced applications in wearable electronics, structural composites, and energy storage devices.

Methods

Raw materials

Ti₃AlC₂ powders (particle size ~400 mesh) were obtained from Laizhou Kai Kai Ceramic Materials Co., Ltd. CS dispersions were obtained from OCSiAl (TUBALL™, SWCNTs, Batch 01RW02.N1, the mass ratio of SWCNT to CMC is approximately 1:1.5). According to the supplier’s information, the SWCNTs had a length of approximately 5 μm, a diameter of 1–2 nm, and a purity of 88.3 wt%. Sodium Carboxymethyl Cellulose (CMC) was purchased from Shanghai Titan Scientific Co., Ltd. (Shanghai, China). Lithium fluoride (LiF) was purchased from Aladdin Reagent. Acetic acid was purchased from Acros Organics. Methanol was purchased from Tianjin Kangkede Technology Co., Ltd. (Tianjin, China). Magnesium sulfate anhydrous was purchased from Shanghai Macklin Biochemical Co., Ltd.

Synthesis of Ti₃C₂T_x MXene nanosheets

A solution of 3.2 g LiF in 40 mL of 9 M HCl was stirred for 15 min. Then, 2 g of Ti₃AlC₂ powder (400 mesh) was gradually added and the reaction was maintained at 35 °C under continuous stirring for 24 h. The product was repeatedly centrifuged at 5000 rpm for 1 min per cycle until the supernatant reached pH > 5. The resulting sediment was redispersed in ethanol and ultrasonicated for 20 min. This dispersion was centrifuged at 8000 rpm for 40 min. The collected precipitate was then mixed with distilled water, ultrasonicated again for 20 min, and centrifuged at 3500 rpm to obtain a homogeneous MXene suspension. The yield of the prepared single-layer MXene was approximately 30–35%.

Synthesis of CS-MXene, C-MXene, and neat MXene fibers

The CS aqueous dispersion was first vortexed for 20 min and then mixed with the MXene aqueous dispersion, followed by an additional 20 min of vortex treatment (optimized MXene-to-CS mass ratio = 1:0.0012). The mixture was centrifuged at 18,000 rpm for 30 min to obtain a high-concentration MXene/CS spinning dope (MXene concentration = 220 mg mL⁻¹). A 1 mL aliquot of the dope was loaded into a 3 mL syringe (Becton Dickinson) equipped with a 26 G needle bent at 45°. The dope was extruded at a rate of 5 mL·h⁻¹ into an acetic acid coagulation bath to form an initial fiber. The as-spun fiber was then immersed in a MgSO₄/methanol solution (2.7 wt% MgSO₄) for 20 min. The fibers were subsequently subjected to hot-pressing at a pressure of 11 kPa, following a procedure reported in our previous work²⁶. Finally, the fiber was vacuum-dried at 120 °C for 2 h to yield the CS-MXene fiber. Neat MXene fibers and C-MXene fibers (containing 0.12 wt% of CMC) were prepared using an identical procedure.

Material characterization

The morphology of the synthesized fibers was examined using SEM (JSM-7800, Japan). Chemical composition analysis was performed via XPS using an ESCALAB 250XI system (Thermo Fisher Scientific, USA). X-ray diffraction measurements were conducted using a 3 kW Rigaku Smart Lab diffractometer (Rigaku, Japan) in the 2θ range of 3°–80° at a scan rate of 8° min⁻¹. The topography of the MXene and CNT were observed using transmission electron microscopy (JEM-2800, Japan) and AFM using a MultiMode system from Bruker. FT-IR spectroscopy was performed using the Thermo Scientific Nicolet IS50 spectrometer with a 4000–500 cm⁻¹ wavenumber range. Two-dimensional correlation spectroscopy (2D-COS) was combined with FT-IR to monitor the strong ionic interactions within MXene fibers. The 2D-COS calculations were performed following Noda’s method¹. Differential scanning calorimeter (DSC) measurements were carried out using a TA DSC25 instrument at heating/cooling rates of 10 °C/min.

Reporting summary

Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.

Supplementary information

Supplementary information^{(4.7MB, pdf)}

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Description of Additional Supplementary File

Supplementary Movie 1^{(23.7MB, mp4)}

Supplementary Movie 2^{(8.7MB, mp4)}

Supplementary Movie 3^{(10MB, mp4)}

Supplementary Movie 4^{(14.1MB, mp4)}

Reporting Summary^{(2MB, pdf)}

Transparent Peer Review file^{(951KB, pdf)}

Source data

Source Data^{(99MB, xlsx)}

Acknowledgements

We would also like to thank Wei Zhang (College of Electronic Information and Optical Engineering, Nankai University) and Qiuping Zhang (State Key Laboratory of Medicinal Chemical Biology, Nankai University) for their technical support in the structural characterization of the materials.

Author contributions

H.W. and J.G. contributed equally to this work. J.L., H.W., and J.G. conceived the idea and designed the experiments. J.L. supervised the research project. H.W., J.G., C.L., D.L., W.Z., X.Z., and X.J. conducted the experiments. All authors contributed to experiments and data analysis. J.L., H.W., J.G., and Y.C. wrote the manuscript.

Peer review

Peer review information

Nature Communications thanks Ken Aldren Usman, Han Gi Chae, and Bhagya Dharmasiri for their contribution to the peer review of this work. A peer review file is available.

Funding

This work was supported by the National Key R&D Program of China (2022YFA1203304), the National Natural Science Foundation of China (52473214, 52173238, and 52503093).

Data availability

All data are available in the main text or the Supplementary Materials. Source data are provided with this paper.

Competing interests

The authors declare no competing interests.

Footnotes

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

These authors contributed equally: Huihui Wang, Jianfeng Gu.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1038/s41467-026-76585-2.

References

1.Zhou, T. et al. Ultra-compact MXene fibers by continuous and controllable synergy of interfacial interactions and thermal drawing-induced stresses. Nat. Commun.13, 4564 (2022). [DOI] [PMC free article] [PubMed] [Google Scholar]
2.Zhou, T. et al. Interlocking-governed ultra-strong and highly conductive MXene fibers through fluidics-assisted thermal drawing. Adv. Mater.35, 2305807 (2023). [DOI] [PubMed] [Google Scholar]
3.Chang, D. et al. Reversible fusion and fission of graphene oxide-based fibers. Science372, 614–617 (2021). [DOI] [PubMed] [Google Scholar]
4.Eom, W. et al. Large-scale wet-spinning of highly electroconductive MXene fibers. Nat. Commun.11, 2825 (2020). [DOI] [PMC free article] [PubMed] [Google Scholar]
5.Xiong, J. Q., Chen, J. & Lee, P. S. Functional fibers and fabrics for soft robotics, wearables, and human-robot interface. Adv. Mater.33, 2002640 (2021). [DOI] [PMC free article] [PubMed] [Google Scholar]
6.Weng, W., Chen, P., He, S., Sun, X. & Peng, H. Smart electronic textiles. Angew. Chem., Int. Ed.55, 6140–6169 (2016). [DOI] [PubMed] [Google Scholar]
7.Li, X. et al. MXene chemistry, electrochemistry and energy storage applications. Nat. Rev. Chem.6, 389–404 (2022). [DOI] [PubMed] [Google Scholar]
8.Zhu, Y. et al. Joule heating synthesis of carbon fiber/graphene 3D crosslinked structure for lightning strike protection and electromagnetic interference in aerospace composites. Chem. Eng. J.474, 145583 (2023). [Google Scholar]
9.Koziol, K. et al. High-performance carbon nanotube fiber. Science318, 1892–1895 (2007). [DOI] [PubMed] [Google Scholar]
10.Zhu, H. et al. Direct synthesis of long single-walled carbon nanotube strands. Science296, 884–886 (2002). [DOI] [PubMed] [Google Scholar]
11.Tran, T. Q., Fan, Z., Liu, P., Myint, S. M. & Duong, H. M. Super-strong and highly conductive carbon nanotube ribbons from post-treatment methods. Carbon99, 407–415 (2016). [Google Scholar]
12.Gu, J. et al. Extremely robust and multifunctional nanocomposite fibers for strain-unperturbed textile electronics. Adv. Mater.35, 2209527 (2023). [DOI] [PubMed] [Google Scholar]
13.Zhang, J. et al. Additive-free MXene liquid crystals and fibers. ACS Cent. Sci.6, 254–265 (2020). [DOI] [PMC free article] [PubMed] [Google Scholar]
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17.Xu, Z. et al. Ultrastiff and strong graphene fibers via full-scale synergetic defect engineering. Adv. Mater.28, 6449–6456 (2016). [DOI] [PubMed] [Google Scholar]
18.Li, S. et al. Assembly of nanofluidic MXene fibers with enhanced ionic transport and capacitive charge storage by flake orientation. ACS Nano15, 7821–7832 (2021). [DOI] [PubMed] [Google Scholar]
19.Yang, J. et al. Water-induced strong isotropic MXene-bridged graphene sheets for electrochemical energy storage. Science383, 771–777 (2024). [DOI] [PubMed] [Google Scholar]
20.Ding, L. et al. Covalently bridging graphene edges for improving mechanical and electrical properties of fibers. Nat. Commun.15, 4880 (2024). [DOI] [PMC free article] [PubMed] [Google Scholar]
21.Aierken, Y., Sevik, C., Gülseren, O., Peeters, F. M. & Çakır, D. MXenes/graphene heterostructures for Li battery applications: a first principles study. J. Mater. Chem. A6, 2337–2345 (2018). [Google Scholar]
22.Li, P. et al. Highly crystalline graphene fibers with superior strength and conductivities by plasticization spinning. Adv. Funct. Mater.30, 2006584 (2020). [Google Scholar]
23.Zhang, J. et al. Highly conductive Ti₃C₂T_x MXene hybrid fibers for flexible and elastic fiber-shaped supercapacitors. Small15, 1804732 (2019). [DOI] [PubMed] [Google Scholar]
24.Usman, K. A. S. et al. Tension-induced toughening and conductivity enhancement in sequentially bridged MXene fibers. 2D Mater.9, 044003 (2022). [Google Scholar]
25.Wan, S. et al. High-strength scalable MXene films through bridging-induced densification. Science374, 96–99 (2021). [DOI] [PubMed] [Google Scholar]
26.Gu, J. et al. Biomimetic strong and tough MXene fibers with synergy between micropores and dual interfaces. Nat. Commun.16, 9645 (2025). [DOI] [PMC free article] [PubMed] [Google Scholar]
27.He, Y. et al. Oriented assembly and bridging of 2D nanosheets enabled high-performance MXene composite fiber via dual-spatially confined spinning. Adv. Funct. Mater.35, 2419923 (2025). [Google Scholar]
28.Li, Y. & Zhang, X. Electrically conductive, optically responsive, and highly orientated Ti₃C₂T_x MXene aerogel fibers. Adv. Funct. Mater.32, 2107767 (2022). [Google Scholar]
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32.Zhang, W. A Study of Discovered Armors and Helmets from Pre-Qin to Han Dynasties (Zhengzhou University, 2005).
33.Du, J. et al. Design of flexible MXene/graphene-based fiber fabrics for broadband electromagnetic wave absorption. Adv. Fiber Mater.7, 811–826 (2025). [Google Scholar]
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35.Eom, W. et al. Carbon nanotube-reduced graphene oxide fiber with high torsional strength from rheological hierarchy control. Nat. Commun.12, 396 (2021). [DOI] [PMC free article] [PubMed] [Google Scholar]
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37.Zhang, X. et al. Carbon nanotube fibers with dynamic strength up to 14 GPa. Science384, 1318–1323 (2024). [DOI] [PubMed] [Google Scholar]
38.Wang, H. et al. Synergizing electron and ion transports of Ti₃C₂T_X MXene fiber via dot-sheet heterostructure and covalent Ti-C-Ti cross-linking for efficient charge storage and thermal management. Adv. Funct. Mater.34, 2408508 (2024). [Google Scholar]
39.Pan, L. et al. Spinning dope modulation via pH-triggered multiscale sheet-wire linkages for constructing strong Ti₃C₂T_X MXene fibers with high volumetric capacitance. Adv. Funct. Mater.1, 2505247 (2025). [Google Scholar]
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51.Gao, E. et al. Microstructural ordering of nanofibers in flow-directed assembly. Sci. China Technol. Sci.62, 1545–1554 (2019). [Google Scholar]
52.Shi, X. et al. Bioinspired ultrasensitive and stretchable MXene-based strain sensor via nacre-mimetic microscale “brick-and-mortar” architecture. ACS Nano13, 649–659 (2019). [DOI] [PubMed] [Google Scholar]
53.Xu, L. et al. Preparation of sodium carboxymethyl cellulose/two-dimensional metal carbide composite xerogel by phytic acid crosslinking for uranium recovery. Chem. Eng. J.502, 157935 (2024). [Google Scholar]
54.Yang, R., Wang, H., Hua, J. & Li, J. Intercalation of sodium carboxymethyl cellulose with MXene membrane layer spacing regulation and monovalent/divalent ion separation. Sep. Purif. Technol.354, 128812 (2025). [Google Scholar]
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57.Zhang, X. et al. Ultrastrong, stiff, and lightweight carbon-nanotube fibers. Adv. Mater.19, 4198–4201 (2007). [Google Scholar]
58.Cheng, B. & Wu, P. Scalable fabrication of Kevlar/Ti₃C₂T_x MXene intelligent wearable fabrics with multiple sensory capabilities. ACS Nano15, 8676–8685 (2021). [DOI] [PubMed] [Google Scholar]
59.Shin, H. et al. Highly electroconductive and mechanically strong Ti₃C₂T_x MXene fibers using a deformable MXene gel. ACS Nano15, 3320–3329 (2021). [DOI] [PubMed] [Google Scholar]
60.van Duin, A. C. T., Dasgupta, S., Lorant, F. & Goddard, W. A. ReaxFF: a reactive force field for hydrocarbons. J. Phys. Chem. A105, 9396–9409 (2001). [Google Scholar]
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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supplementary information^{(4.7MB, pdf)}

41467_2026_76585_MOESM2_ESM.pdf^{(169.5KB, pdf)}

Description of Additional Supplementary File

Supplementary Movie 1^{(23.7MB, mp4)}

Supplementary Movie 2^{(8.7MB, mp4)}

Supplementary Movie 3^{(10MB, mp4)}

Supplementary Movie 4^{(14.1MB, mp4)}

Reporting Summary^{(2MB, pdf)}

Transparent Peer Review file^{(951KB, pdf)}

Source Data^{(99MB, xlsx)}

Data Availability Statement

All data are available in the main text or the Supplementary Materials. Source data are provided with this paper.

[CR1] 1.Zhou, T. et al. Ultra-compact MXene fibers by continuous and controllable synergy of interfacial interactions and thermal drawing-induced stresses. Nat. Commun.13, 4564 (2022). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR2] 2.Zhou, T. et al. Interlocking-governed ultra-strong and highly conductive MXene fibers through fluidics-assisted thermal drawing. Adv. Mater.35, 2305807 (2023). [DOI] [PubMed] [Google Scholar]

[CR3] 3.Chang, D. et al. Reversible fusion and fission of graphene oxide-based fibers. Science372, 614–617 (2021). [DOI] [PubMed] [Google Scholar]

[CR4] 4.Eom, W. et al. Large-scale wet-spinning of highly electroconductive MXene fibers. Nat. Commun.11, 2825 (2020). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR5] 5.Xiong, J. Q., Chen, J. & Lee, P. S. Functional fibers and fabrics for soft robotics, wearables, and human-robot interface. Adv. Mater.33, 2002640 (2021). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR6] 6.Weng, W., Chen, P., He, S., Sun, X. & Peng, H. Smart electronic textiles. Angew. Chem., Int. Ed.55, 6140–6169 (2016). [DOI] [PubMed] [Google Scholar]

[CR7] 7.Li, X. et al. MXene chemistry, electrochemistry and energy storage applications. Nat. Rev. Chem.6, 389–404 (2022). [DOI] [PubMed] [Google Scholar]

[CR8] 8.Zhu, Y. et al. Joule heating synthesis of carbon fiber/graphene 3D crosslinked structure for lightning strike protection and electromagnetic interference in aerospace composites. Chem. Eng. J.474, 145583 (2023). [Google Scholar]

[CR9] 9.Koziol, K. et al. High-performance carbon nanotube fiber. Science318, 1892–1895 (2007). [DOI] [PubMed] [Google Scholar]

[CR10] 10.Zhu, H. et al. Direct synthesis of long single-walled carbon nanotube strands. Science296, 884–886 (2002). [DOI] [PubMed] [Google Scholar]

[CR11] 11.Tran, T. Q., Fan, Z., Liu, P., Myint, S. M. & Duong, H. M. Super-strong and highly conductive carbon nanotube ribbons from post-treatment methods. Carbon99, 407–415 (2016). [Google Scholar]

[CR12] 12.Gu, J. et al. Extremely robust and multifunctional nanocomposite fibers for strain-unperturbed textile electronics. Adv. Mater.35, 2209527 (2023). [DOI] [PubMed] [Google Scholar]

[CR13] 13.Zhang, J. et al. Additive-free MXene liquid crystals and fibers. ACS Cent. Sci.6, 254–265 (2020). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR14] 14.Yu, C. et al. A solid-state fibriform supercapacitor boosted by host–guest hybridization between the carbon nanotube scaffold and MXene nanosheets. Small14, 1801203 (2018). [DOI] [PubMed] [Google Scholar]

[CR15] 15.Cao, X. et al. High-performance Zn²⁺-crosslinked MXene fibers for versatile flexible electronics. Adv. Funct. Mater.34, 2407975 (2024). [Google Scholar]

[CR16] 16.Wan, S. et al. High-strength scalable graphene sheets by freezing stretch-induced alignment. Nat. Mater.20, 624–631 (2021). [DOI] [PubMed] [Google Scholar]

[CR17] 17.Xu, Z. et al. Ultrastiff and strong graphene fibers via full-scale synergetic defect engineering. Adv. Mater.28, 6449–6456 (2016). [DOI] [PubMed] [Google Scholar]

[CR18] 18.Li, S. et al. Assembly of nanofluidic MXene fibers with enhanced ionic transport and capacitive charge storage by flake orientation. ACS Nano15, 7821–7832 (2021). [DOI] [PubMed] [Google Scholar]

[CR19] 19.Yang, J. et al. Water-induced strong isotropic MXene-bridged graphene sheets for electrochemical energy storage. Science383, 771–777 (2024). [DOI] [PubMed] [Google Scholar]

[CR20] 20.Ding, L. et al. Covalently bridging graphene edges for improving mechanical and electrical properties of fibers. Nat. Commun.15, 4880 (2024). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR21] 21.Aierken, Y., Sevik, C., Gülseren, O., Peeters, F. M. & Çakır, D. MXenes/graphene heterostructures for Li battery applications: a first principles study. J. Mater. Chem. A6, 2337–2345 (2018). [Google Scholar]

[CR22] 22.Li, P. et al. Highly crystalline graphene fibers with superior strength and conductivities by plasticization spinning. Adv. Funct. Mater.30, 2006584 (2020). [Google Scholar]

[CR23] 23.Zhang, J. et al. Highly conductive Ti₃C₂T_x MXene hybrid fibers for flexible and elastic fiber-shaped supercapacitors. Small15, 1804732 (2019). [DOI] [PubMed] [Google Scholar]

[CR24] 24.Usman, K. A. S. et al. Tension-induced toughening and conductivity enhancement in sequentially bridged MXene fibers. 2D Mater.9, 044003 (2022). [Google Scholar]

[CR25] 25.Wan, S. et al. High-strength scalable MXene films through bridging-induced densification. Science374, 96–99 (2021). [DOI] [PubMed] [Google Scholar]

[CR26] 26.Gu, J. et al. Biomimetic strong and tough MXene fibers with synergy between micropores and dual interfaces. Nat. Commun.16, 9645 (2025). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR27] 27.He, Y. et al. Oriented assembly and bridging of 2D nanosheets enabled high-performance MXene composite fiber via dual-spatially confined spinning. Adv. Funct. Mater.35, 2419923 (2025). [Google Scholar]

[CR28] 28.Li, Y. & Zhang, X. Electrically conductive, optically responsive, and highly orientated Ti₃C₂T_x MXene aerogel fibers. Adv. Funct. Mater.32, 2107767 (2022). [Google Scholar]

[CR29] 29.Xin, G. et al. Highly thermally conductive and mechanically strong graphene fibers. Science349, 1083–1087 (2015). [DOI] [PubMed] [Google Scholar]

[CR30] 30.Natu, V., Sokol, M., Verger, L. & Barsoum, M. W. Effect of edge charges on stability and aggregation of Ti₃C₂T_z MXene colloidal suspensions. J. Phys. Chem. C122, 27745–27753 (2018). [Google Scholar]

[CR31] 31.Natu, V. et al. Edge capping of 2D-MXene sheets with polyanionic salts to mitigate oxidation in aqueous colloidal suspensions. Angew. Chem., Int. Ed.58, 12655–12660 (2019). [DOI] [PubMed] [Google Scholar]

[CR32] 32.Zhang, W. A Study of Discovered Armors and Helmets from Pre-Qin to Han Dynasties (Zhengzhou University, 2005).

[CR33] 33.Du, J. et al. Design of flexible MXene/graphene-based fiber fabrics for broadband electromagnetic wave absorption. Adv. Fiber Mater.7, 811–826 (2025). [Google Scholar]

[CR34] 34.Dai, H. et al. Bio-inspired interfacial engineering of MXene fibers toward synergistic improvement in mechanical strength and electrochemical performance. Adv. Funct. Mater.34, 2312654 (2024). [Google Scholar]

[CR35] 35.Eom, W. et al. Carbon nanotube-reduced graphene oxide fiber with high torsional strength from rheological hierarchy control. Nat. Commun.12, 396 (2021). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR36] 36.Zhang, M., Atkinson, K. R. & Baughman, R. H. Multifunctional carbon nanotube yarns by downsizing an ancient technology. Science306, 1358–1361 (2004). [DOI] [PubMed] [Google Scholar]

[CR37] 37.Zhang, X. et al. Carbon nanotube fibers with dynamic strength up to 14 GPa. Science384, 1318–1323 (2024). [DOI] [PubMed] [Google Scholar]

[CR38] 38.Wang, H. et al. Synergizing electron and ion transports of Ti₃C₂T_X MXene fiber via dot-sheet heterostructure and covalent Ti-C-Ti cross-linking for efficient charge storage and thermal management. Adv. Funct. Mater.34, 2408508 (2024). [Google Scholar]

[CR39] 39.Pan, L. et al. Spinning dope modulation via pH-triggered multiscale sheet-wire linkages for constructing strong Ti₃C₂T_X MXene fibers with high volumetric capacitance. Adv. Funct. Mater.1, 2505247 (2025). [Google Scholar]

[CR40] 40.Wang, H. et al. Interlayer manipulation for accelerating ion diffusion kinetics in Ti₃C₂T_X MXene fiber toward enhanced supercapacitance with high rate capability. Nano Lett.25, 6405–6413 (2025). [DOI] [PubMed] [Google Scholar]

[CR41] 41.Lee, D. et al. Ultrahigh strength, modulus, and conductivity of graphitic fibers by macromolecular coalescence. Sci. Adv.8, eabn0939 (2022). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR42] 42.Liu, K. et al. Scratch-resistant, highly conductive, and high-strength carbon nanotube-based composite yarns. ACS Nano4, 5827–5834 (2010). [DOI] [PubMed] [Google Scholar]

[CR43] 43.Bandyopadhyaya, R., Nativ-Roth, E., Regev, O. & Yerushalmi-Rozen, R. Stabilization of individual carbon nanotubes in aqueous solutions. Nano Lett.2, 25–28 (2002). [Google Scholar]

[CR44] 44.Hajian, A., Lindström, S. B., Pettersson, T., Hamedi, M. M. & Wågberg, L. Understanding the dispersive action of nanocellulose for carbon nanomaterials. Nano Lett.17, 1439–1447 (2017). [DOI] [PubMed] [Google Scholar]

[CR45] 45.Feng, X. et al. Highly conductive and multifunctional nanocomposites based on sulfated nanocellulose-assisted high dispersion limit of single-walled carbon nanotubes. Carbon183, 187–195 (2021). [Google Scholar]

[CR46] 46.Olivier, C. et al. Cellulose nanocrystal-assisted dispersion of luminescent single-walled carbon nanotubes for layer-by-layer assembled hybrid thin films. Langmuir28, 12463–12471 (2012). [DOI] [PubMed] [Google Scholar]

[CR47] 47.Zhang, Y. et al. Ultrastrong bioinspired graphene-based fibers via synergistic toughening. Adv. Mater.28, 2834–2839 (2016). [DOI] [PubMed] [Google Scholar]

[CR48] 48.Zhou, T. et al. Ultrastrong MXene composite fibers through static-dynamic densification for wireless electronic textiles. Nat. Commun.16, 10968 (2025). [DOI] [PMC free article] [PubMed] [Google Scholar]

[CR49] 49.Flory, P. J. Statistical thermodynamics of mixtures of rodlike particles. 5. Mixtures with random coils. Macromolecules11, 1138–1141 (1978). [Google Scholar]

[CR50] 50.Yan, D. et al. Carbon nanotube-directed 7 GPa heterocyclic aramid fiber and its application in artificial muscles. Adv. Mater.36, 2306129 (2024). [DOI] [PubMed] [Google Scholar]

[CR51] 51.Gao, E. et al. Microstructural ordering of nanofibers in flow-directed assembly. Sci. China Technol. Sci.62, 1545–1554 (2019). [Google Scholar]

[CR52] 52.Shi, X. et al. Bioinspired ultrasensitive and stretchable MXene-based strain sensor via nacre-mimetic microscale “brick-and-mortar” architecture. ACS Nano13, 649–659 (2019). [DOI] [PubMed] [Google Scholar]

[CR53] 53.Xu, L. et al. Preparation of sodium carboxymethyl cellulose/two-dimensional metal carbide composite xerogel by phytic acid crosslinking for uranium recovery. Chem. Eng. J.502, 157935 (2024). [Google Scholar]

[CR54] 54.Yang, R., Wang, H., Hua, J. & Li, J. Intercalation of sodium carboxymethyl cellulose with MXene membrane layer spacing regulation and monovalent/divalent ion separation. Sep. Purif. Technol.354, 128812 (2025). [Google Scholar]

[CR55] 55.Li, W., Sun, B. & Wu, P. Study on hydrogen bonds of carboxymethyl cellulose sodium film with two-dimensional correlation infrared spectroscopy. Carbohydr. Polym.78, 454–461 (2009). [Google Scholar]

[CR56] 56.Tang, P. et al. Tough, strong, and conductive graphene fibers by optimizing surface chemistry of graphene oxide precursor. Adv. Funct. Mater.32, 2112156 (2022). [Google Scholar]

[CR57] 57.Zhang, X. et al. Ultrastrong, stiff, and lightweight carbon-nanotube fibers. Adv. Mater.19, 4198–4201 (2007). [Google Scholar]

[CR58] 58.Cheng, B. & Wu, P. Scalable fabrication of Kevlar/Ti₃C₂T_x MXene intelligent wearable fabrics with multiple sensory capabilities. ACS Nano15, 8676–8685 (2021). [DOI] [PubMed] [Google Scholar]

[CR59] 59.Shin, H. et al. Highly electroconductive and mechanically strong Ti₃C₂T_x MXene fibers using a deformable MXene gel. ACS Nano15, 3320–3329 (2021). [DOI] [PubMed] [Google Scholar]

[CR60] 60.van Duin, A. C. T., Dasgupta, S., Lorant, F. & Goddard, W. A. ReaxFF: a reactive force field for hydrocarbons. J. Phys. Chem. A105, 9396–9409 (2001). [Google Scholar]

[CR61] 61.Plimpton, S. Fast parallel algorithms for short-range molecular dynamics. J. Comput. Phys.117, 1–19 (1995). [Google Scholar]

PERMALINK

In-plane molecular cord bridging as a method for boosting MXene fiber strength and toughness

Huihui Wang

Jianfeng Gu

Chao Li

Donghui Li

Weiqing Zhan

Xinmin Zhang

Xinyi Ji

Yongsheng Chen

Jiajie Liang

Abstract

Introduction

Fig. 1. Design and fabrication of CS-MXene fibers.

Results and discussion

Design and fabrication of CS-MXene fibers

Characterization of CS-bridged MXene nanosheets

Fig. 2. Structural characterizations.

Mechanical properties of CS-MXene fibers

Fig. 3. Mechanical and electrical properties for MXene, C-MXene, and CS-MXene fibers.

Strengthening and toughening mechanism

Fig. 4. Analyses of strengthening and toughening mechanism for CS-MXene fibers.

Robust multifunctional performance

Fig. 5. Multifunctional performance of CS-MXene fibers.

Methods

Raw materials

Synthesis of Ti3C2Tx MXene nanosheets

Synthesis of CS-MXene, C-MXene, and neat MXene fibers

Material characterization

Reporting summary

Supplementary information

Source data

Acknowledgements

Author contributions

Peer review

Peer review information

Funding

Data availability

Competing interests

Footnotes

Supplementary information

References

Associated Data

Supplementary Materials

Data Availability Statement

ACTIONS

PERMALINK

RESOURCES

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Synthesis of Ti₃C₂T_x MXene nanosheets