How the fluorographene replaced graphene as nanoadditive for improving tribological performances of GTL-8 based lubricant oil
Xiaojing Ci,
Wenjie Zhao,
Jun Luo,
Yangmin Wu,
Tianhao Ge,
Qunji Xue,
Xiulei Gao,
Zhiwen Fang
Affiliations
Xiaojing Ci
Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences
Wenjie Zhao
Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences
Jun Luo
School of Materials and Engineering, Shanghai University
Yangmin Wu
Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences
Tianhao Ge
Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences
Qunji Xue
Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences
Xiulei Gao
Engineering Technology Research Center of Fluorocarbon Materials, Shandong Zhongshan Photoelectric Materials Co., Ltd.
Zhiwen Fang
Engineering Technology Research Center of Fluorocarbon Materials, Shandong Zhongshan Photoelectric Materials Co., Ltd.
Abstract Fluorographene, a new alternative to graphene, it not only inherits the 2-dimensional (2D) layered structure and outstanding mechanical properties, but also possesses controllable C–F bonds. It is meaningful to reveal the evolution processes of the tribological behaviors from graphene to fluorographene. In this work, fluorinated reduced graphene oxide nanosheets (F–rGO) with different degree of fluorination were prepared using direct gas-fluorination and they were added into gas to liquid-8 (GTL-8) base oil as lubricant additive to improve the tribological performance. According to the results, the coefficient of friction (COF) reduced by 21%, notably, the wear rate reduced by 87% with the addition of highly fluorinated reduced graphene oxide (HF–rGO) compared with rGO. It was confirmed that more covalent C–F bonds which improved the chemical stability of HF–rGO resisted the detachment of fluorine so the HF–rGO nanosheets showed less damage, as demonstrated via X-ray photoelectron spectroscopy (XPS), Raman spectra, and transmission electron microscopy (TEM). Meanwhile, the ionic liquid (IL) adsorbed on HF–rGO successfully improved the dispersibility of F–rGO in GTL-8 base oil. The investigation of tribofilm by TEM and focused ion beam (FIB) illustrated that IL displayed a synergy to participate in the tribochemical reaction and increased the thickness of tribofilm during the friction process.
