• 文献标题:   In Situ Synthesis of Graphene Nitride Nanolayers on Glycerol-Lubricated Si3N4 for Superlubricity Applications
  • 文献类型:   Article
  • 作  者:   LONG Y, KUWAHARA T, BOUCHET MID, RISTIC A, DORR N, LUBRECHT T, DUPUY L, MORAS G, MARTIN JM, MOSELER M
  • 作者关键词:   silicon nitride, graphene nitride layer, tribochemistry, boundary lubrication, superlubricity
  • 出版物名称:   ACS APPLIED NANO MATERIALS
  • ISSN:  
  • 通讯作者地址:  
  • 被引频次:   12
  • DOI:   10.1021/acsanm.0c03362 EA FEB 2021
  • 出版年:   2021

▎ 摘  要

The increasing demand for sustainable tribology has accelerated the development of environmentally friendly lubrication solutions such as water or water-related lubricants. Earlier works have reported on water-lubricated sliding of silicon nitride (Si3N4) at high speeds, which can result in a superlow friction (mu < 0.01) owing to the formation of hydrodynamic water films on hydrophilic surface layers. Here, combined boundary-lubrication experiments at low sliding speeds and atomistic simulations reveal an alternative superlubricity mechanism for glycerol-lubricated Si3N4. X-ray photoelectron and time-of-flight secondary ion mass spectrometry performed inside and outside the wear track as well as high-resolution mass spectroscopy of the used lubricant strongly suggest that sub-nanometer-thick graphene nitride layers form at the very top of Si3N4. In the accompanying atomistic simulations, glycerol molecules undergo tribochemical decomposition and react with surface-bound nitrogen atoms to form carbon nitrides. Further shearing promotes the formation of 2D graphene nitrides that passivate the ceramic surfaces and induce a superlow friction under boundary lubrication. Thus, glycerol-lubricated Si3N4 has a high potential for use in green superlubricity enabled by in situ synthesis of disordered graphene nitride species.