Unlocking exceptional EMI shielding in Ti₃C₂T _x MXenes through controlled microstructure and surface chemistry

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Highly integrated electronics require advanced electromagnetic interference (EMI) shielding materials.
• Existing materials often lack the combination of lightweight, flexibility, and high shielding effectiveness.
• Titanium carbide (Ti3C2Tx) MXene shows promise for EMI shielding applications.

Purpose of the Study:

• To fabricate high-performance EMI shields using additive-free Ti3C2Tx MXene dispersions.
• To engineer freestanding thin films and functionalized cotton fabrics with tunable shielding properties.
• To establish structure-property relationships for optimizing EMI shielding performance.

Main Methods:

• Synthesis of Ti3C2Tx MXene dispersions under varying etching conditions.
• Fabrication of freestanding films and functionalized cotton fabrics via vacuum-assisted filtration.
• Characterization of material properties and EMI shielding effectiveness (SE).

Main Results:

• A 13 μm thick film achieved an EMI shielding of 60 dB.
• A freestanding, heat-treated 5 μm thick Ti3C2Tx film demonstrated 71 dB SE (99.99999% attenuation) and an ultrahigh absolute shielding effectiveness (SSE_T) of 72,300 dB cm² g⁻¹.
• Coated cotton fabric achieved an unprecedented SE of 82 dB with excellent environmental stability, retaining performance after six months.

Conclusions:

• Optimized Ti3C2Tx MXene films and fabrics offer superior EMI shielding performance.
• Key factors for enhanced shielding include induced porosity, meta-structure effects, large flake size, and optimized surface terminations.
• This work provides a framework for developing advanced, scalable EMI shielding solutions for flexible and wearable electronics.