Intercalation-Induced Interlayer and Defect Engineering in Ti₃C₂T MXene for Ultralow-Reflection Electromagnetic...

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Electrical conductivity and electromagnetic interference (EMI) shielding of Ti₃C₂T MXene are significantly influenced by interlayer and defect engineering.
• Prior research has focused on intercalant size, neglecting chemical affinity, which hinders understanding of intercalation mechanisms and precise control over interlayer spacing (d-spacing).

Purpose of the Study:

• To synthesize MXene aerogels with tunable d-spacing and defect density.
• To investigate the impact of amine intercalants with varying sizes and chemical affinities on MXene properties.
• To develop advanced materials for efficient EMI shielding.

Main Methods:

• Synthesis of MXene aerogels using a series of amine molecules as intercalants and cross-linkers.
• Tuning of d-spacing and defect density through controlled intercalation.
• Characterization of structural and electrical properties.
• Evaluation of EMI shielding performance, focusing on absorptivity and shielding effectiveness.

Main Results:

• Intercalation with p-phenylenediamine (PPD) increased MXene d-spacing from 0.960 to 1.642 nm.
• Increased d-spacing led to higher defect density within the Ti-Ti layer.
• PPD@MXene aerogel demonstrated absorption-dominated EMI shielding with absorptivity of 0.92 and shielding effectiveness of 50.4 dB.
• Reduced surface electric field intensity and increased internal polarization loss were observed.

Conclusions:

• The study successfully engineered MXene aerogels with controlled d-spacing and defect density using amine intercalants.
• The PPD@MXene aerogel exhibits exceptional EMI shielding performance, primarily through absorption.
• This work provides a foundation for developing advanced, interlayer-engineered MXene shielding materials.