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Page 14 of 57 Zheng et al. Soft Sci. 2026, 6, 32

to incorporate active components. Using the solidification bath as a chemical reactor is one noteworthy
invention. In order to facilitate amidation interactions with carboxyl groups at the margins of GO, Ding et al.
used an amine compound solution as the solidification bath . As seen in Figure 5I, this method
[63]
concurrently created a strong covalent network during shaping, accomplishing integrated
“solidification-crosslinking”. In order to create very uniform composite fibers with a consistent composition,
Guo et al. used a microfluidic spinning technique to instantly combine reactants at the minuscule scale .
[80]
This is the process’s most advanced level of precision. Additionally, post-processing methods are essential for
figuring out the fibers’ final characteristics. By decreasing porosity and greatly increasing the alignment of
GO layers along the fiber axis, the drawing process simultaneously increases mechanical strength and
electrical conductivity. This procedure can be applied either in the gel form or following drying through
“plastic stretching”. By applying intercalation plastic stretching to GO gel fibers, Shi et al. greatly enhanced
the orientation and density of decreased fibers [Figure 5J] .
[78]

Wet-spinning is now a programmable framework for structural modulation, having progressed from
creating individual structures. By using coaxial spinning and flow field design to gain continuous control
over lamellar arrangement, Hao et al. laid the groundwork for functionally configurable smart fibers . As
[81]
seen in Figure 5K, the multi-shear flow field-assisted spinning method created by Li et al. allows for the
programming of different ordered textures such as concentric and helical patterns within the fiber
cross-section, resulting in synergistic advances in mechanical and thermal properties . Zhi et al. used
[52]
substrate-assisted drying techniques to create fibers with distinctive heterogeneous structures in terms of
fiber morphological innovation . Their unique morphologies give devices wide detection ranges and great
[56]
sensitivity [Figure 5L and M].

Wet spinning is a very adjustable method of precision preparation to fabricate GFs. It is possible to precisely
regulate the microstructure, mechanical, electrical, and functional properties of graphene-based fibers by
methodical optimization and creative design of the spinning solution, coagulation bath, spinning process,
and post-treatment techniques. This creates an ideal fabrication platform for the widespread application of
soft graphene-based conductive fibers in high-performance smart fabrics.Several interrelated processing
parameters control the conversion of GO’s inherent characteristics into macroscopic fiber performance.
Throughput and orientation efficiency are directly influenced by spinning speed: Shi et al. used a 100-hole
spinneret to achieve continuous production at 75 m·h -1[78] , while Martinez et al. used a high-speed
dual-diffusion strategy to push the limits of graphene/liquid crystal composite fibers to 4,500 m·h -1[42] .
However, extreme speeds require some trade-off in mechanical properties. A moderate draw ratio of 1.3
times improves electrical conductivity by 56% , while plastic drawing at 2.0 to 3.0 times simultaneously
[12]
increases density, orientation, and elastic modulus . Draw ratio also plays a significant impact. Large flakes
[78]
(> 20 μm) favor high orientation and modulus (reaching 901 GPa when paired with small-flake filling ),
[50]
whereas small flakes (<​ 5 μm) increase processability but decrease mechanical strength. GO flake size
determines liquid crystallinity and defect density. Solvent exchange kinetics are controlled by the
solidification bath’s composition: functional baths, such amine solutions, allow for in situ cross-linking,
whereas retarding agents, like ethanol/water mixes, create denser structures . Post-treatment factors have a
[63]
significant impact on modulus retention and electrical conductivity (up to 1.2 × 10 S·cm ), especially
6
-1
thermal reduction temperature (≥ 3,000 °C for graphitization) . These factors are still closely related, and a
[17]
major obstacle to converting lab discoveries into commercial GF manufacturing is precisely optimizing their
synergistic effects.

Other fabrication methods
In order to meet the specific requirements of various applications for fiber structure, characteristics, and
preparation procedures, a number of alternative spinning techniques have been developed in addition to
conventional wet-spinning techniques. Every technique has its own unique features; some concentrate on