Flexoelectricity in Monolayer Transition Metal Dichalcogenides
Wenhao Shi1, Yufeng Guo1, Zhuhua Zhang1
1State Key Laboratory of Mechanics and Control of Mechanical Structures and MOE Key Laboratory for Intelligent Nano Materials and Devices, College of Aerospace Engineering , Nanjing University of Aeronautics and Astronautics , Nanjing 210016 , China.
The Journal of Physical Chemistry Letters
|November 20, 2018
Summary
Structural wrinkling in transition metal dichalcogenide (TMD) monolayers induces significant flexoelectricity. This strain-gradient effect, tunable by wrinkle wavelength, shows promise for energy conversion devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Flexoelectricity couples strain gradients to electric polarization.
- Low-dimensional materials offer tunable electronic properties.
- Transition metal dichalcogenide (TMD) monolayers are promising nanomaterials.
Purpose of the Study:
- To investigate flexoelectricity in wrinkled transition metal dichalcogenide (TMD) monolayers.
- To understand the relationship between structural corrugation and flexoelectric effects.
- To develop a theoretical model for flexoelectricity in these systems.
Main Methods:
- Extensive first-principles calculations.
- Analysis of structural wrinkling and corrugation effects.
- Development of a theoretical model based on symmetry and calculations.
Main Results:
- Wrinkling and corrugation induce significant flexoelectricity in TMD monolayers.
- Flexoelectricity is driven by strain gradients across the monolayer thickness.
- The effect becomes more pronounced with shorter wrinkle wavelengths.
- A theoretical model accurately describes the out-of-plane polarization.
Conclusions:
- Flexoelectricity is an inherent property of wrinkled TMD monolayers.
- The tunability of flexoelectricity offers new avenues for electronic property control.
- Wrinkled TMD monolayers show potential for advanced energy conversion devices.
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