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Updated: Aug 4, 2025
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Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
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Twisting Dynamics of Large Lattice-Mismatch van der Waals Heterostructures
Mengzhou Liao1,2, Andrea Silva3,4, Luojun Du1,5
1Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
ACS Applied Materials & Interfaces
|April 6, 2023
Summary
Rotational friction in 2D heterostructures like MoS2/graphite is angle-dependent, unlike translational friction. Twisting induces potential energy changes, creating rotational resistance even with negligible sliding friction.
Area of Science:
- Tribology
- Materials Science
- Condensed Matter Physics
Background:
- Van der Waals (vdW) heterostructures are key for studying interfacial tribology, including superlubricity.
- Research has focused on translational motion, with rotational dynamics largely unexplored.
Purpose of the Study:
- To investigate the twisting dynamics and rotational friction mechanisms in MoS2/graphite heterostructures.
- To understand the relationship between twist angle, structural potential energy, and rotational resistance.
Main Methods:
- Combined experimental techniques and computational simulations.
- Analyzed the twisting dynamics of MoS2/graphite heterostructures.
Main Results:
- Rotational resistance is highly dependent on twist angles, unlike angle-independent translational friction.
- Periodic rotational resistance arises from structural potential energy changes during twisting.
- Moiré superstructure formation in graphene controls potential energy and rotational resistance.
Conclusions:
- Potential energy changes during twisting provide a non-negligible rotational resistance force in 2D heterostructures.
- Structural changes offer an additional energy dissipation pathway, enhancing rotational friction.
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