Graphene enhances the loading capacity and lubrication performance of ionic liquids: a molecular dynamics study

• Main Authors: Jiang, Haodong, Wang, Yaoze, Xiong, Zhipeng, Zhou, Runhua, Yang, Linyan, Bai, Lichun
• Other Authors: Energy Research Institute @ NTU (ERI@N)
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Materials; Graphene; Ionic Liquid Lubricants
• Online Access: https://hdl.handle.net/10356/171731
• Institution: Nanyang Technological University

Ionic liquid (IL) combined with graphene additives have garnered extensive attention in the field of high-performance lubricating materials. However, the ambiguous mechanism of graphene influencing the load-carrying and anti-wear capacity of ILs needs further study. In this work, friction simulation shows that adding graphene causes friction coefficient to reduce by up to 88% compared with pure ILs, but lubrication performance is lost due to the destruction of graphene under high stress. Meanwhile, multilayer graphene has better friction-reducing performance and friction durability as compared to the monolayer structure, which is attributed to the easy-shear property and the reduction in the percentage of high tensile stress sites in multilayer graphene structure. In addition, it was found that excessively thick ILs film would form a three-body abrasive wear structure with graphene, which accelerated the structural destruction of graphene and caused a decline in its tribological properties. It is believed these findings can be valuable for designing of high-performance lubricating oil for practical engineering.