N-Functionalized MXenes: ultrahigh carrier mobility and multifunctional properties

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) nanomaterials are crucial for advanced applications, including nanodevices and energy technologies.
• MXenes represent a versatile class of 2D materials with tunable properties.

Purpose of the Study:

• To investigate the electronic properties of novel nitrogen-functionalized MXenes (Nb2CN2 and Ta2CN2).
• To explore the potential of these materials for high-performance nanodevices.

Main Methods:

• Density-functional theory (DFT) calculations were employed to model and analyze the material properties.
• The effects of biaxial and uniaxial strain on electronic structures were systematically studied.

Main Results:

• Nb2CN2 and Ta2CN2 monolayers were identified as direct semiconductors with near-linear energy dispersions.
• These materials exhibit exceptionally small effective mass and ultra-high carrier mobility (up to 10^6 cm^2 V^-1 s^-1).
• Electronic properties, including band gap and carrier mobility, are tunable via strain engineering, enabling direct-indirect band gap transitions.

Conclusions:

• Nitrogen-functionalized MXenes possess highly desirable electronic properties for advanced applications.
• The strain-tunable nature of these materials makes them promising candidates for high-speed and low-power nanodevices.