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Zheng et al. Soft Sci. 2026, 6, 32 Page 15 of 57

increasing production efficiency, others on creating distinctive morphologies, and yet others on optimizing
process flows. However, they typically struggle to achieve balanced overall performance, cost management,
or continuous manufacturing. Their development can be seen as a useful extension and potent supplement
to the conventional wet-spinning method.

Dry and dry-to-wet spinning
In dry spinning, a high-concentration spinning solution is extruded straight from the spinneret, where the
solvent evaporates in the air to solidify and produce the fiber. Figure 6A depicts a schematic of the dry
spinning procedure. This process permits solvent recovery, does not require a coagulation bath, and is
comparatively eco-friendly. However, mechanical strength is usually low and porous fibers may result from
solvent evaporation. By twisting and stretching GO films into fibers made of graphene nanorolls, Zheng et al.
used a twist-spinning assembly technique . Figure 6B and C show the fiber structure, while Figure 6D
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shows how layered entanglement improves mechanical properties. Organic-inorganic composite fibers can
also be prepared by dry spinning. For example, Zhang et al. used covalent crosslinking to create
photothermal-responsive smart actuator fibers by combining surface-modified GO with liquid crystal
elastomers . Figure 6E and F illustrates the connection between driving strain and time under light/heat
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stimulation.

The orienting benefits of dry spinning and the solidification features of wet spinning are combined in
dry-wet spinning. In order to prepare structurally thick, highly orientated fibers, the spinning solution is
subjected to air-gap stretching prior to entering the solidification bath. This technique was used by Xiang
et al. to create GFs with high orientation and smooth surfaces . However, the procedure’s complicated
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process control restricts its widespread use, and it frequently depends on extremely corrosive solvents like
chlorosulfonic acid to create the liquid crystal spinning solution.

Electrospinning
As seen in Figure 6G, electrospinning is a popular method for creating nanofibers by applying ultrafine
stretching via high-voltage electrostatic forces to polymer solutions or melts. This method has been
effectively expanded to produce graphene-based nanofibers in recent years. By adding transient polymer
additives, Han et al. invented the electrospinning of continuous, pure graphene nanofibers and achieved
noticeably improved electrical conductivity following graphitization . This technique makes it easier to
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build three-dimensional networks of porous fibers, which makes it appropriate for uses like flexible
electrodes. Park et al. created porous graphene nanofibers in a single step by combining electrospinning and
laser photothermal treatment to further enhance the structure . Figure 6H displays SEM images at various
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solution concentrations, showing noticeably improved electrochemical performance. However, controlling
the macroscopic mechanical characteristics of the fibers is difficult since electrospinning usually necessitates
the use of polymer spinning aids and entails several following processing steps.

Method of confined hydrothermal assembly
Constrained hydrothermal assembly operates on the basis of thermally induced self-assembly under spatial
confinement instead of shear flow orientation, which is a major difference from wet spinning. Typically, a
glass or polytetrafluoroethylene capillary with an inner diameter of tens to hundreds of micrometers is
injected with a high-concentration GO aqueous solution (2-10 mg·mL at pH ≈ 6-7) . Under self-generated
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-1
pressure, the sealed capillary is heated to 80-230 °C, which sets off a sequence of interconnected
physicochemical changes. Three synergistic processes take place simultaneously under hydrothermal
conditions: capillary-induced confinement, where the cylindrical geometry of the capillary imposes
one-dimensional spatial constraints, guiding randomly oriented layers into highly aligned fibrillar
morphologies during hydrogel curing; π-π stacking drives self-assembly, where restored conjugated domains