Tough yet low-hysteresis conductive hydrogels for energy-efficient wearable electronics

Area of Science:

• Materials Science
• Polymer Chemistry
• Soft Electronics

Background:

• Conductive hydrogels are vital for soft electronics but struggle with balancing toughness and low hysteresis.
• The inherent conflict between energy dissipation and elastic recovery in polymer networks poses a significant challenge.

Purpose of the Study:

• To engineer a novel conductive hydrogel with enhanced toughness and reduced hysteresis.
• To overcome the limitations of existing materials for applications in soft electronics.

Main Methods:

• Synthesized a copolymer network of acrylamide (AM) and N-acryloyl tris(hydroxymethyl)aminomethane (THMA).
• Incorporated MXene nanosheets and a hydrophobic ionic liquid (1-hexadecyl-3-methylimidazolium bromide) for reinforcement and property modulation.
• Investigated synergistic interactions between components to enhance mechanical and electrical properties.

Main Results:

• Achieved ultrahigh stretchability (3548%) and high toughness (15.3 MJ/m³).
• Demonstrated exceptionally low hysteresis (4% at 100% tensile strain), mitigating the toughness-hysteresis trade-off.
• Developed flexible strain sensors with fast and stable electromechanical responses.

Conclusions:

• The developed hydrogel offers a generalizable strategy for coordinating energy dissipation and elastic recovery in conductive materials.
• This work provides insights for designing mechanically robust and energy-efficient soft materials for advanced applications.