Robust, flexible, and high-performance electromagnetic interference shielding films with long-lasting service.

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Long-lasting electromagnetic interference (EMI) shielding materials are crucial for electronic devices.
• Existing materials often degrade over time, reducing their effectiveness.
• Improving the durability of hybrid shielding materials is an ongoing challenge.

Purpose of the Study:

• To enhance the durability of silver nanowire (AgNW) and nickel nanoparticle (NiNP) hybrid papers for EMI shielding applications.
• To investigate the effect of waterborne polyurethane (WPU) coating on the performance and longevity of these hybrid papers.
• To confirm the suitability of the modified hybrid papers for practical, long-term use.

Main Methods:

• Fabrication of hybrid papers by dip-coating WPU onto AgNW networks with sputter-deposited NiNPs.
• Characterization of the WPU coating coverage and the hybrid papers' properties (electrical conductivity, magnetic properties, EMI shielding effectiveness).
• Durability testing, including tape peeling resistance and long-term air exposure (5 months).

Main Results:

• A WPU layer effectively coated the hybrid paper surface after five dip-coating cycles.
• The WPU coating did not negatively impact the shielding effectiveness (SE) (∼80 dB).
• The coated hybrid papers showed improved tape peeling resistance and maintained SE after 5 months of air exposure.
• Achieved electrical conductivity of ∼3500 S m⁻¹, remnant magnetization of 0.03 emu g⁻¹, saturation magnetization of 0.10 emu g⁻¹, and coercivity of 256 Oe.

Conclusions:

• WPU coating significantly enhances the durability of AgNW/NiNP hybrid papers without compromising EMI shielding performance.
• The isolation effect of the WPU coating protects the hybrid material from environmental degradation, ensuring long-lasting effectiveness.
• The developed hybrid papers meet the stringent requirements for practical, durable EMI shielding applications.