Demethylated Lignin@Liquid Metal Nanospheres Enabling Versatile Conductive Hydrogel for Self-Powered Soft Electronics

Area of Science:

• Materials Science
• Polymer Chemistry
• Biotechnology

Background:

• Conductive hydrogels are crucial for smart electronics but face challenges in low-cost, rapid fabrication with integrated properties.
• Achieving superior mechanical robustness, conductivity, adhesion, and self-healing simultaneously remains a significant hurdle.

Purpose of the Study:

• To develop a versatile, biomass-based conductive hydrogel with enhanced properties using a novel synthesis approach.
• To integrate functional components for improved gelation, mechanical strength, and conductivity for soft electronics.

Main Methods:

• Synthesis of a hydrogel (DLLMH) incorporating demethylated lignin (DL) coated liquid metal (LM) nanospheres (DL@LM).
• Utilizing DL@LM to accelerate free-radical polymerization, acting as a stabilizing agent and enhancing energy dissipation.
• Characterization of mechanical properties, conductivity, adhesion, and self-healing capabilities.

Main Results:

• The synthesized DLLMH hydrogel exhibited excellent mechanical properties (3.77 MJ/m³), conductivity (2.14 mS/cm), and adhesion (36.47 MPa).
• Liquid metal significantly accelerated polymerization (280 s) without external heating or UV, while lignin prevented overpolymerization and precipitation.
• The hydrogel demonstrated effective self-healing and was used in strain/temperature sensors and a self-powered triboelectric nanogenerator (TENG).

Conclusions:

• The developed biomass-based hydrogel offers a sustainable and efficient route for creating advanced conductive materials.
• This approach provides a valuable method for the value-added utilization of lignin in soft electronics and energy harvesting.
• The DLLMH hydrogel shows significant potential for applications in human-computer interaction and flexible electronic devices.