Strain-Insensitive Stretchable Fiber Conductors Based on Highly Conductive Buckled Shells for Wearable Electronics

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Fiber-based stretchable electronics are crucial for wearable applications.
• Degradation of electrical conductivity upon stretching limits current fiber electrodes.
• Existing conductive buckled structures struggle to balance high conductivity and stretchability.

Purpose of the Study:

• To fabricate a strain-insensitive stretchable fiber conductor with high conductivity and stretchability.
• To address the limitations of current fiber electrodes in wearable electronics.
• To demonstrate the applicability of the developed fibers in strain-tolerant sensors.

Main Methods:

• Exploiting a dense network of silver nanoparticles (AgNPs) within a polyurethane (PU) matrix.
• Utilizing a facile chemical process to create highly conductive buckled shells.
• Characterizing electrical conductivity, strain insensitivity, and durability under cyclic stretching.

Main Results:

• Achieved a high electrical conductivity of 26,128 S/m and a quality factor (Q) of 2.29.
• Demonstrated stable electrical responses up to ~200% tensile strain with negligible hysteresis.
• Exhibited excellent durability exceeding 10,000 stretching-releasing cycles.
• Developed functional buckled fiber-based pH sensors with stable and repeatable responses under 100% strain.

Conclusions:

• The developed buckled AgNP/PU fibers offer a facile strategy for strain-insensitive stretchable conductors.
• These fibers maintain stable electrical performance across the strain range of human motion.
• The technology shows high applicability for advanced wearable electronics and sensors.