1. State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, P.R. China
2. Key Laboratory of Science and Technology on Wear and protection of Materials, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, P.R. China
3. Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering, Yantai, P.R. China