1. CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, and CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology of China, Beijing 100049, China
2. University of Chinese Academy of Sciences, Beijing 100049, China
3. IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, United States
4. NSF’s ChemMatCARS and Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
5. CAS Key Laboratory of Standardization and Measurement for Nanotechnology and CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology, Beijing 100190, China
6. Department of Chemistry, Columbia University, New York, New York 10027, United States