1. Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, California 94720, United States
2. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
3. Department of Mechanical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
4. Department of Physics and Astronomy, University of New Hampshire, Durham, New Hampshire 03824, United States
5. Canadian Centre for Electron Microscopy, McMaster University, Hamilton ,ON L8S 4L8, Canada
6. 2D Crystal Consortium, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
7. Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
8. Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
9. Department of Mining, Metallurgy, and Materials Engineering, University of the Philippines, Diliman, Quezon City 1101, Philippines
10. Queensland Micro- and Nanotechnology Centre, Griffith University, Brisbane, 4111 Australia
11. The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
12. Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
13. Department of Materials Science and Engineering, McMaster University, Hamilton ,ON L8S 4L8, Canada