Stimuli-Responsive MXene/PNIPAM Hydrogel WITH High-Performance and Tunable Electromagnetic Interference Shielding...

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Smart electromagnetic interference (EMI) shielding materials with reversible responses are crucial for flexible electronic devices.
• Existing materials often lack dynamic control over shielding capabilities.

Purpose of the Study:

• To fabricate novel, stimuli-responsive hydrogels for switchable EMI shielding.
• To investigate the relationship between hydrogel structure, water content, and EMI shielding performance.
• To demonstrate real-time electrical switching of EMI shielding in a broad frequency range.

Main Methods:

• Fabrication of poly (N-isopropylacrylamide) (PNIPAM) and MXene/PEDOT: PSS hybrid filler PPM hydrogels using ice-templated freeze-in-situ polymerization.
• Anisotropic structural design for enhanced mechanical and conductive properties.
• Utilizing thermal and light stimuli to dynamically alter internal water content and modulate EMI shielding.

Main Results:

• PPM hydrogels exhibited tunable EMI shielding, transitioning from >50 dB (on) to ≈2 dB (off) in the X-band.
• Quantitative adjustment of EMI shielding effectiveness (SE) from ≈59.3 dB to 15.5 dB with excellent repeatability.
• Achieved real-time electrical switching of EMI shielding across a broad GHz frequency range (8.2-40 GHz) via dual stimuli-responsive modulation.

Conclusions:

• The developed PPM hydrogels offer a new model for dynamically switchable EMI shielding.
• These smart hydrogels demonstrate significant potential for next-generation multifunctional electronics requiring on/off EMI shielding capabilities.