Solution-Blown Aligned Nanofiber Yarn and Its Application in Yarn-Shaped Supercapacitor

Area of Science:

• Materials Science
• Energy Storage
• Nanotechnology

Background:

• Flexible yarn-shaped supercapacitors are crucial for the advancement of smart wearable devices.
• Existing methods for producing nanofiber yarn electrodes face challenges in mass production and performance optimization.

Purpose of the Study:

• To develop a continuous production method for oriented nanofiber yarn electrodes.
• To fabricate and characterize flexible yarn-shaped supercapacitors with enhanced electrochemical performance and mechanical properties.

Main Methods:

• A solution blowing technique was employed for continuous production of oriented nanofiber yarn.
• Yarn electrodes were constructed using aligned carbon fiber bundles coated with polypyrrole (PPy) grown on polyacrylonitrile (PAN) nanofibers (CFs@PAN NFs).
• The assembled yarn-shaped supercapacitors utilized a PVA/LiCl/H3PO4 gel electrolyte.

Main Results:

• The yarn electrodes demonstrated improved electrical conductivity and mechanical strength due to carbon fiber bundles.
• Polypyrrole (PPy) significantly increased the specific surface area of the yarn electrodes.
• Supercapacitors achieved a high areal specific capacitance of 353 mF cm⁻² at 0.1 A g⁻¹, with an energy density of 48 μWh cm⁻² at a power density of 247 μW cm⁻².
• Excellent cycle stability was observed, retaining 82% capacity after 20,000 cycles.
• The supercapacitors successfully powered a light-emitting diode.

Conclusions:

• The developed solution blowing method enables mass production of oriented nanofiber yarn electrodes for flexible supercapacitors.
• The fabricated yarn-shaped supercapacitors exhibit promising electrochemical performance, mechanical flexibility, and cycle stability.
• These findings hold significant implications for the integration of energy storage into smart wearable devices and textiles.