1. Center for Nanochemistry (CNC) Beijing Science and Engineering Center for Nanocarbons Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 P. R. China
2. Beijing Graphene Institute (BGI) Beijing 100095 P. R. China
3. State Key Laboratory of Heavy Oil Processing College of Science China university of Petroleum Beijing 102249 P. R. China
4. Key Laboratory of Opto‐Electronics Technology Ministry of Education College of Electronic Science and Technology Faculty of Information Technology Beijing University of Technology Beijing 100024 P. R. China
5. Information Materials and Intelligent Sensing Laboratory of Anhui Province Institute of Physical Science and Information Technology Anhui University Hefei 230039 P. R. China