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Updated: Aug 6, 2026
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Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
Published on: July 11, 2025
Tunable Friction with Nonmonotonic Enhancement via Interlayer Rotation-Induced Moiré Superlattices
Yun Dong1, Yifeng Zhang1, Chunjie Zhang1
1School of Mechanical and Electrical Engineering, Lanzhou University of Technology, Lanzhou730050, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 20, 2026
Summary
Researchers explored friction control using molybdenum disulfide (MoS2) models. Friction peaks were observed at specific tip sizes related to moiré superlattices, offering new ways to regulate friction.
Area of Science:
- Materials Science
- Tribology
- Condensed Matter Physics
Background:
- Friction plays a dual role in technological systems, necessitating advanced regulation strategies beyond simple lubrication.
- Understanding friction at the atomic scale is crucial for developing novel control methods.
Purpose of the Study:
- To investigate the relationship between interlayer rotation, moiré superlattices, and friction in a MoS2-based model.
- To identify mechanisms governing friction variation and explore novel friction regulation techniques.
Main Methods:
- Construction of a friction model using a monolayer MoS2 tip and a rotating bilayer MoS2 substrate.
- Analysis of friction behavior as a function of rotation angle and tip size.
- Examination of atomic contact, phonon coupling, and surface topography changes induced by moiré superlattices.
Main Results:
- Friction showed nonmonotonic behavior with increasing rotation angle.
- Friction peaks occurred when tip size matched the moiré superlattice period or its half.
- Atomic contact, phonon coupling, and topography were identified as key factors influencing friction variation.
Conclusions:
- Interlayer interactions and tip-substrate coupling are intrinsic mechanisms for friction regulation.
- Tip size and interlayer rotation mode offer a novel approach to control friction in MoS2 systems.
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