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Page 12 of 57 Zheng et al. Soft Sci. 2026, 6, 32

Alongside fibers like cotton and polyester, GFs can be integrated with traditional textile processes (like
knitting and weaving) due to their exceptional flexibility and weavability. This offers a material basis for the
functional realization and structural design of smart textiles. However, because to structural flaws, improper
orientation, and insufficient density during the manufacturing process, their macroscopic mechanical and
electrical properties typically stay below theoretical values and those of some commercial carbon-based
fibers. Thus, by optimizing graphene building blocks, controlling the fiber’s “tertiary structure” (layer
orientation, pore distribution, and interfacial bonding), enhancing spinning methods, and perfecting
post-treatment techniques, current research aims to improve the overall performance of GFs. The goal of this
strategy is to effectively convert graphene’s microscopic nanosheet benefits into macroscopic fiber assembly
performance.

Fabrication strategies
Since graphene’s intrinsic insolubility prevents it from being used directly in spinning techniques, its
oxidized counterpart, GO, is now used as a precursor in the manufacturing of GFs. Because GO surfaces are
abundant in oxygen-containing functional groups like hydroxyl, epoxy, and carboxyl groups, they have
exceptional dispersibility in polar solvents (such water and N,N-dimethylformamide) and can form a
nematic liquid crystal phase at specific concentrations. This property provides the basis for using
solution-based techniques to achieve the ordered macroscopic assembly of graphene units. Wet spinning,
dry spinning, dry-to-wet spinning, electrospinning, restricted hydrothermal assembly, film winding, and
template-assisted CVD are the main fiber production techniques that researchers have developed based on
the solution processability of GO. Due to its excellent compatibility with conventional textile systems and
simplicity of scaling, wet spinning has emerged as the most used fabrication method.

Wet spinning
The most scalable method for creating continuous, high-performance graphene-based fibers is wet spinning.
By extruding a GO dispersion with nematic liquid crystal behavior into a coagulation bath, phase separation
solidification, drawing, and reduction post-treatment enable continuous fiber manufacturing . Figure 5A
[11]
shows a constant wet spinning configuration. The dual diffusion and phase separation processes are essential
to the core quality of fiber production. Solvent outward diffusion and coagulant inward diffusion happen at
the same time when a fine stream of GO solution is injected into the coagulation bath. The microstructure
and compactness of the fiber are directly determined by the kinetic rate of this process. Studies show that the
development of fibers with more homogeneous architectures and fewer flaws is facilitated by relatively slow
diffusion processes. Effective fiber solidification is only possible in certain thermodynamic zones, and this
process adheres to the phase diagram principles of a ternary system (GO, solvent, coagulant). By enhancing
the dual-diffusion mechanism, Martinez et al. showed that this method is scalable, allowing for flexible
control over fiber diameter and high-speed spinning [Figure 5B] . GF filament bundles with a significant
[42]
length and consistent structure were successfully produced by Shi et al. using a 100-hole spinneret for
continuous spinning at speeds up to 75 m/h . As seen in Figure 5C-E, their morphology creates a process
[78]
foundation for practical smart textile applications.

The spinnability and ultimate performance of the fibers are significantly influenced by the characteristics of
the spinning solution, specifically the size and concentration of GO sheets. Nematic liquid crystals, which are
essential for obtaining highly ordered macroscopic layer assembly and creating high-performance fibers, can
be formed by GO dispersions over the critical concentration. Researchers frequently use GO’s liquid crystal
characteristics to direct wet spinning in real-world applications. Ma et al. established the groundwork for
creating high-performance fiber electrodes by using rheological tests to confirm the exceptional spinnability
of liquid crystal mother liquors . With the structural history shown in Figure 5F-H, Li et al. further mapped
[79]
the structural phase diagram of GO liquid crystals at various concentrations and shear forces, offering