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Fluctuation-induced quantum friction in nanoscale water flows
Nikita Kavokine1,2, Marie-Laure Bocquet3, Lydéric Bocquet4
1Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France. nikita.kavokine@ens.fr.
Nature
|February 3, 2022
Summary
A new quantum theory explains water friction in carbon nanochannels. This quantum friction, driven by charge fluctuations and electronic excitations, differs between graphene and graphite, explaining flow anomalies.
Area of Science:
- Physics
- Materials Science
- Quantum Mechanics
Background:
- Water flow in carbon nanochannels exhibits unexplained phenomena like ultra-low friction and curvature-dependent slippage.
- Existing theories and simulations fail to adequately explain the mechanism of water-carbon friction.
Purpose of the Study:
- To develop a quantum theory for the solid-liquid interface to understand water-carbon friction.
- To identify the dominant friction mechanism in water-carbon systems.
Main Methods:
- Development of a quantum theory for the solid-liquid interface.
- Investigating the coupling of charge fluctuations in water with electronic excitations in carbon materials.
- Comparing quantum friction at water-graphene and water-graphite interfaces.
Main Results:
- A novel quantum friction mechanism is revealed, arising from coupled charge fluctuations and electronic excitations.
- Quantum friction is identified as the dominant mechanism, surpassing classical and ab initio molecular dynamics.
- Significant differences in quantum friction were observed between water-graphene and water-graphite interfaces.
Conclusions:
- The quantum friction theory provides a satisfactory explanation for the unique behavior of water in carbon nanochannels.
- The findings suggest that electronic excitations in nanotubes explain radius-dependent slippage.
- This research enables quantum engineering of hydrodynamic flows by manipulating wall electronic properties.
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