Environmentally stable and stretchable polymer electronics enabled by surface-tethered nanostructured molecular-level...

Area of Science:

• Materials Science
• Polymer Chemistry
• Organic Electronics

Background:

• Stretchable polymer semiconductors (PSCs) are crucial for developing soft electronics.
• Environmental instability, particularly in the presence of moisture and biofluids, hinders the practical application of PSCs.
• Existing encapsulation methods are often bulky and less effective.

Purpose of the Study:

• To develop a robust and thin protective layer for stretchable polymer semiconductors.
• To enhance the operational stability of PSCs in challenging environmental conditions.
• To enable the use of stretchable electronics in direct contact with physiological fluids.

Main Methods:

• Covalent functionalization of fluoroalkyl chains onto PSC surfaces.
• Formation of densely packed, nanostructured fluorinated molecular protection layers (FMPLs).
• Characterization of FMPL properties including hydrophobicity, thickness, and protective capabilities.

Main Results:

• The FMPL (~6 nm) demonstrated superior protection compared to thicker polymer encapsulants.
• PSCs with FMPL maintained stable charge carrier mobility (~1 cm^2 V^-1 s^-1) for extended periods (up to 82 days) in humid air, water, and artificial sweat.
• The FMPL effectively blocked water absorption and diffusion, and improved resistance to photo-oxidative degradation.

Conclusions:

• Surface-tethered nanostructured FMPLs offer a highly effective strategy for achieving environmentally stable stretchable polymer electronics.
• This approach significantly enhances the durability and reliability of PSCs for applications involving physiological fluids.
• The developed FMPL technology paves the way for advanced, long-lasting soft electronic devices.