Lignin Crosslinked Ultrastable ANF-CNT Films for Photo-Thermal-Electric Conversion and Joule Heating

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Aramid nanofibers (ANF) are promising for wearable devices due to toughness and stability.
• Surface activation remains a challenge for ANF applications.
• Lignin's structural similarity to ANF offers potential for surface modification.

Purpose of the Study:

• To activate ANF using lignin for improved composite properties.
• To create ANF-CNT composites with enhanced mechanical, stability, and conductivity.
• To explore the photo-thermal-electric and Joule heating capabilities of the composite films.

Main Methods:

• Lignin was used to activate ANF.
• Composites of ANF and carbon nanotubes (CNT) were fabricated via vacuum filtration.
• Thermal-crosslinking processes were applied to the composites.
• Interfacial binding mechanisms (hydrogen bonding, π-π stacking, covalent bonds) were analyzed.

Main Results:

• The ALxCy (TC) films exhibited enhanced tensile strength (∼88.6 MPa) and toughness (∼77.2 MJ m⁻³).
• Improved stability in solvents, temperature (-20°C-100°C), and under deformation was observed.
• Enhanced conductivity (∼148.2 S m⁻¹) and superior photo-thermal-electric conversion (∼62°C, 150 mV) were achieved.
• Favorable Joule heating properties (∼105°C) were demonstrated.

Conclusions:

• Lignin effectively activates ANF, improving interfacial compatibility with CNT.
• The resulting composite films possess excellent mechanical, stability, conductivity, and energy conversion properties.
• This work presents a green and efficient method for developing advanced composite films for energy management.