Abstract:

Significance Carbon nanotube fibers (CNTFs), as macroscopic materials assembled from aligned individual carbon nanotubes (CNTs), have garnered significant attention by virtue of their exceptional physical and chemical properties, such as high strength, high thermal conductivity, flexibility, and electrical conductivity. These characteristics make CNTFs highly promising for applications in fiber sensors, energy storage devices, and flexible electronics. However, challenges in the controlled fabrication and functionalization of CNTFs hinder their broader application. This review systematically explores the preparation methods and performance regulation strategies of CNTFs, summarizes recent advancements across multiple fields, and outlines future directions and challenges in this area.
Progress CNTFs retain the remarkable properties of individual CNTs on a macroscopic scale, making them suitable for a wide range of advanced applications. Various fabrication techniques, such as wet spinning, array drawing, and floating catalytic chemical vapor deposition, have been developed to assemble CNTs into fibers. However, these methods face challenges, including insufficient CNT length, poor alignment and the presence of defects and impurities, limiting the full realization of their intrinsic properties. Post-treatment techniques, such as pressing, stretching, and twisting, have been employed to enhance the alignment and mechanical properties of CNTFs, achieving tensile strengths up to 9.6 GPa and electrical conductivities of 1.06×10⁷ S/m. Compared to conventional metal and polymer fibers, CNTFs exhibit superior performance in terms of tensile strength, Young's modulus, conductivity, thermal conductivity, surface area, and flexibility. These advantages make CNTFs highly promising for applications in flexible electronics, sensors, and wearable devices.
Conclusion and Prospect Significant progress has been made in the synthesis techniques and performance optimization of CNTFs in recent years. However, critical challenges, such as defect control, efficient large-scale production, and the development of novel functionalization strategies, remain to be addressed. Future research should focus on scalable production while maintaining high material quality and performance. Additionally, more advanced methods for performance tuning will further promote the development of CNTFs in flexible electronics, energy storage devices, and other applications. As a novel type of functional material, CNTFs hold great promise for future advancements.

Key words: carbon nanotube fiber, controlled synthesis method, performance regulation, multi level structure design, sensor, energy storage device