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Updated: Sep 11, 2025
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Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions
Published on: June 6, 2017
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Superlubricity Between Alkane Molecules and Graphite: Effect of Alkane Chain Length
Zhuolin Wu1, Yutong Xiong2,3, Yongfeng Yang1
1State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing, 100084, China.
Small (Weinheim an Der Bergstrasse, Germany)
|August 13, 2025
Summary
Longer alkane molecules, like hexadecane, enhance graphite’s lubrication by aligning on the surface. This study reveals optimal molecular structures for superior friction reduction in advanced lubrication systems.
Area of Science:
- Tribology
- Materials Science
- Nanotechnology
Background:
- Graphite is a known lubricant additive with excellent friction-reducing properties.
- The ideal molecular structure of oil for optimal graphite lubrication is not fully understood.
Purpose of the Study:
- To investigate the synergistic lubrication between graphite and alkane molecules of varying chain lengths.
- To determine how alkane chain length influences the lubrication performance with graphite.
Main Methods:
- Atomic Force Microscopy (AFM)
- Scanning Tunneling Microscopy (STM)
- Molecular Dynamics (MD) simulations
Main Results:
- Superlubricity was achieved in a hexadecane environment, yielding a friction coefficient of 0.001.
- This represents an over 80% friction reduction compared to dodecane and nonane.
- Ordered alignment of long-chain alkanes on graphite surfaces facilitated stable confined layers and low-energy boundary slip.
Conclusions:
- Alkane chain length is critical in modulating the synergistic lubrication mechanism between alkanes and graphite.
- Ordered molecular alignment and boundary slip are key to achieving ultralow friction.
- Findings provide guidance for designing high-performance lubrication systems using graphite nanoflakes.
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