为探寻解决微/纳机电系统中摩擦和磨损等界面效应问题的理想新方法,研究了石墨接触界面对石墨超润滑的影响及阻力来源.首先,利用电子束曝光、反应离子束刻蚀等微加工方法制备了微米级石墨平台,并使用微纳机械手推动石墨平台获得了具有超润滑特性的石墨表面.然后使用拉曼光谱、纳米级红外光谱和原子力显微镜对获得的超润滑石墨表面进行表征.最后使用了能谱仪对石墨平台进行了微区元素分析.结果表明,超润滑石墨表面具有原子级光滑的平整度,并具有极高的有序度,而石墨表面的边缘具有多种缺陷并在加工过程中及大气环境中吸附了多种分子,边缘的氧原子含量比面内氧原子含量高出了24.2%.推动石墨平台的过程中,边缘吸附分子会阻碍超润滑石墨接触界面发生相对滑动,克服这些分子的吸附需要能量,这成为摩擦阻力的来源.%In order to seek for a new ideal method to solve friction,abrasion and other interfacial effect problems in micro/nano electro mechanical system,the influence of graphite contact interfaces on graphite superlubricity and the sources of resistance were researched.First,the electron beam lithography,ion beam etching and other micro-processing methods were used to prepare microscale graphite mesa,and graphite surface with superlubricity was obtained by using micro-nano manipulator to shear the graphite mesa.Then,the Raman spectrum,nanoscale infrared spectrum and atomic force microscope were used to characterize the surface of the obtained superlubricity graphite.Finally,energy dispersive spectrometer was taken to analyze micro-area elements in graphite platform.The result shows that the surface of superlubricity graphite has atomically smooth flatness and has high order degree,but there are multiple defects on the edge of the graphite surface;and multiple molecules are absorbed on the surface of the graphite in the process of machining and in the atmospheric environment.The content of marginal oxygen atom is 24.2% higher than the content of in-plane oxygen atom.In the process of pushing graphite platform,the marginally absorbed molecule will hinder the relative sliding of contact interface of superlubricity graphite.Moreover,energy is needed to overcome the absorption of these molecules,which becomes the source of frictional resistance.
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