Entropy-modulated atomic ripple texturing in two-dimensional transition metal carbonitrides

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) ripple texturing enables modulation of local potential for advanced electronics.
• Controlling atomic ripples in 2D transition metal carbonitrides (MXenes) is challenging due to difficulties in homogeneous deformation.

Purpose of the Study:

• To propose a strategy for controllable modulation of atomic ripple structures in Nb2CTex-based MXenes.
• To establish the relationship between atomic ripple structure, strain, polarization relaxation, and dielectric properties.

Main Methods:

• Leveraging configurational entropy and surface termination to control atomic ripple formation.
• Analyzing the release of in-plane strain by termination atoms to regulate out-of-plane atomic displacement.
• Investigating the regulation of dielectric relaxation time through ripple structure design.

Main Results:

• Achieved controllable atomic ripple structures in Nb2CTex-based MXenes.
• Demonstrated that chemical disorder and termination atoms influence atomic displacement.
• High-entropy MXenes exhibited strong microwave absorption (-41.12 dB) with a 10 GHz bandwidth across S-, C-, and X-bands.

Conclusions:

• The study establishes a link between atomic ripple structure, strain, polarization relaxation, and dielectric properties.
• This work provides a pathway for designing advanced MXenes with tailored electronic properties.
• The findings offer guidance for developing high-performance microwave absorption materials.