Mechanically and Functionally Resilient Piezoelectric Fiber Coils and Knots for Reliable Self-Powered Sensing

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Electrospun poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) nanofibers offer piezoelectric properties for self-powered sensing.
• Integrating electrodes into flexible piezoelectric sensors while maintaining high stretchability and reliability is challenging.

Purpose of the Study:

• To develop a mechanically and functionally resilient piezoelectric coil sensor with high stretchability and long-term reliability.
• To create a fiber-based self-powered sensing platform for multimodal mechanical sensing.

Main Methods:

• Hierarchical design combining a styrene-ethylene-butylene-styrene (SEBS)-assisted interlocked fiber-particle network.
• Multicomponent-doped poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/P(VDF-TrFE) electrode with a gradient interfacial layer.
• Testing stretchability, electromechanical performance under strain and repetitive loading, and multimodal mechanical sensing capabilities.

Main Results:

• Achieved a fully integrated coil sensor with stretchability up to 668%.
• Demonstrated stable electromechanical performance under large strains and repetitive loading.
• Exhibited linear and stable piezoelectric responses to stretching, bending, and compression, enabling quantitative sensing validated by machine learning.
• Showcased adaptive knot configurations maintaining consistent self-powered output under high loads.

Conclusions:

• The hierarchical resilient design enables simultaneous mechanical recoverability and electrical robustness in fiber-based self-powered sensors.
• The developed platform is versatile for wearable healthcare, soft robotics, and surgical assistance.
• This work provides a new route for advanced self-powered sensing applications.