Liquid-Free Ion-Conducting Elastomer with Environmental Stability for Soft Sensing and Thermoelectric Generating

Area of Science:

• Materials Science
• Polymer Chemistry
• Soft Electronics

Background:

• Ionic conductors are crucial for soft electronics but face challenges with liquid leakage and evaporation in hydrogels and organogels.
• Developing stable, free-liquid ionic conductors is essential for reliable soft electronic devices.

Purpose of the Study:

• To fabricate a novel free-liquid ionic conducting elastomer (LFICE) with enhanced stability and performance.
• To investigate the material properties and application potential of the developed LFICE.

Main Methods:

• Fabrication of LFICE using dry lithium bis(trifluoromethane sulfonimide) and elastomeric waterborne polyurethane.
• Characterization of mechanical properties (tensile strength, stretchability), ionic conductivity, and response to strain and temperature.
• Assembly and testing of LFICE-based sensors and thermoelectric generators (TEGs).

Main Results:

• The LFICE demonstrated superior tensile strength (~4.5 MPa), stretchability (>900%), and ionic conductivity (8.32 × 10⁻⁴ S m⁻¹).
• The material exhibited sensitive strain (3.21) and temperature (2.22% °C⁻¹) response with durable environmental stability.
• LFICE sensors accurately detected human motion and temperature, while LFICE TEGs generated a high ionic thermovoltage (4.41 mV K⁻¹).

Conclusions:

• The developed LFICE offers a promising solution for stable, stretchable ionic conductors in next-generation soft electronics.
• LFICE holds significant potential for self-powered soft electronics, digital medical diagnosis, and environmental monitoring applications.
• This work advances the fabrication of robust ionic conductors with integrated sensing and energy harvesting capabilities.