Stretchable PEDOT:PSS/Li-TFSI/XSB Composite Films for Electromagnetic Interference Shielding

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Stretchable electromagnetic interference (EMI) shielding materials are crucial for advanced wearable and flexible electronic devices.
• Existing materials often lack sufficient conductivity, stretchability, or cost-effectiveness for widespread adoption.

Purpose of the Study:

• To develop highly stretchable and efficient EMI shielding composite films.
• To investigate the effect of lithium bis(trifloromethanesulfonyl)imide (Li-TFSI) doping on PEDOT:PSS within a rubber matrix for EMI shielding applications.

Main Methods:

• Preparation of composite films using Li-TFSI-doped PEDOT:PSS and carboxylated styrene-butadiene rubber (XSB) latex.
• Characterization of film morphology, conductivity, and EMI shielding performance at various strain levels.
• Comparison with films using traditional dopants like ethylene glycol.

Main Results:

• The Li-TFSI-doped PEDOT:PSS/XSB films exhibited tenuous conductive pathways, enhancing EMI shielding efficiency (EMI SE).
• Films with 6 wt % PEDOT:PSS and 6 wt % Li-TFSI achieved EMI SE of 50 dB (0% strain) and 30 dB (100% strain) at 12.4 GHz.
• These results represent some of the highest EMI SE values reported for stretchable composites, excluding liquid metal-based materials.

Conclusions:

• The developed composite films offer a promising solution for lightweight, stretchable EMI shielding.
• The simple and environmentally friendly preparation method facilitates future development of materials for flexible electronics.
• The Li-TFSI-doped PEDOT:PSS/XSB system demonstrates superior performance compared to traditional doping methods.