1. Key Laboratory of Cluster ScienceMinistry of Education of ChinaBeijingKey Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of Technology Beijing 100081 P. R. China
2. College of Chemical EngineeringQingdao University of Science & Technology Qingdao City Shandong Province 266042 P. R. China
3. Key Laboratory for Advanced Materials Processing TechnologyMinistry of Education of ChinaState Key Laboratory of TribologyDepartment of Mechanical EngineeringDepartment of ChemistryTsinghua University Beijing 100084 P. R. China