Superlubricity achieved with two-dimensional nano-additives to liquid lubricants

Hongdong WANG; Yuhong LIU

doi:10.1007/s40544-020-0410-3

Friction 2020, 8(6): 1007-1024 https://doi.org/10.1007/s40544-020-0410-3

Review Article |

Open Access | Issue | Published: 23 July 2020

Superlubricity achieved with two-dimensional nano-additives to liquid lubricants

Show Author's Information Hide Author's Information Hongdong WANG, Yuhong LIU(

)

State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China

Keywords:

tribological property, superlubricity, two-dimensional (2D) nanomaterial, lubricant additive, water-based

Cite this article:

WANG H, LIU Y. Superlubricity achieved with two-dimensional nano-additives to liquid lubricants. Friction, 2020, 8(6): 1007-1024. https://doi.org/10.1007/s40544-020-0410-3

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Abstract

The topic of superlubricity is attracting considerable interest around the world while humanity is facing an energy crisis. Since various liquid superlubricity systems can be commonly achieved on the macroscale in ambient conditions, it is considered an effective solution to reduce unnecessary energy and material losses. However, certain practical problems such as low load-bearing pressure, dependence on hydrogen ions, and relatively long running-in processes still limit its widespread application. Two- dimensional (2D) nano-additives with ultrathin longitudinal dimensions can lower the shear resistance between sliding solid surfaces, and thus further optimize the applied conditions. In this review, the latest studies on 2D nano-additives with a combination of various water-based lubricants in the state of superlubricity are reported, typically including black phosphorus (BP), graphene oxide (GO), and layered double hydroxide. During the sliding process, composite lubricants effectively improved the load capacity (up to 600 MPa), reduced wear, and accelerated the running-in period (within 1,000 s) of the liquid superlubricity system. Both macromechanical experiments and microscopic tests are conducted to precisely analyze various interactions at the interfaces of the nano-additives and solid surfaces. These interactions can be described as tribochemical reactions, physical protection, and adsorption enhancement, and improved wear resistance. This review provides better guidance for applying 2D nanomaterials in liquid superlubricity systems.

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Superlubricity achieved with two-dimensional nano-additives to liquid lubricants

Show Author's information Hide Author's Information Hongdong WANG, Yuhong LIU(

)

State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China

Abstract

Keywords: tribological property, superlubricity, two-dimensional (2D) nanomaterial, lubricant additive, water-based

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Publication history

Received: 15 January 2020

Revised: 19 April 2020

Accepted: 26 May 2020

Published: 23 July 2020

Issue date: December 2020

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Acknowledgements

This study was financially supported by the National Natural Science Foundation of China (51905294, 51527901, and 51875303), the China Postdoc Innovation Talent Support Program (BX20180168), and the China Postdoctoral Science Foundation (2019M650654). The authors thank Dr. Jinjin LI for his valuable suggestions.

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