Layer-by-Layer Assembly-Based Heterointerfaces for Modulating the Electronic Properties of Ti₃C₂T MXene

Area of Science:

• Materials Science
• Nanotechnology
• Condensed Matter Physics

Background:

• Two-dimensional (2D) transition-metal carbides (MXenes) possess unique electrical, optical, and optoelectronic properties.
• Modulating the electronic properties of metallic Ti3C2Tx MXene is crucial for nanoelectronic device fabrication.

Purpose of the Study:

• To demonstrate a solution-processable method for creating Ti3C2Tx MXene/CuI nanoparticle heterointerfaces.
• To investigate the charge transfer, oxidation stability, and electrical transport mechanisms of these novel heterointerfaces.

Main Methods:

• Layer-by-layer assembly was used to fabricate Ti3C2Tx MXene/CuI nanoparticle heterointerfaces.
• Photoluminescence quenching monitored charge transfer, while Raman spectroscopy and conductivity measurements assessed stability.
• Electrical transport and magnetoresistance were studied across a temperature range.

Main Results:

• The 3-LBL (three sequential stacks of CuI/MXene) assembly showed stable electrical conductivity and Raman spectra after 2 months of ambient exposure, indicating excellent oxidation stability.
• A transition from weak localized transport in Ti3C2Tx MXene to 3D variable-range hopping in the 3-LBL assembly was observed.
• Distinct magnetoresistance behaviors (negative for MXene, positive for 3-LBL assembly) confirmed the altered charge transport mechanisms.

Conclusions:

• The fabricated Ti3C2Tx MXene/CuI nanoparticle heterointerfaces exhibit enhanced oxidation stability and modulated electrical transport properties.
• These findings suggest potential applications in next-generation optoelectronic and memory devices.