1. School of Materials Science and EngineeringNorthwestern Polytechnical University Xi'an 710072 China
2. Department of Materials Science and NanoEngineeringRice University 6100 Main Street Houston TX 77005 USA
3. School of Materials Science and EngineeringBeihang University Beijing 100191 China
4. Smalley‐Curl InstituteRice University 6100 Main Street Houston TX 77005 USA
5. Department of Physics, Key Laboratory for Computational Science (MOE), State Key Laboratory of Surface PhysicsFudan University Shanghai 200433 China
6. Institute of Nano‐Science and TechnologyHabitat Centre Phase‐10, Sector‐64 Mohali 160062 India
7. Department of ChemistryRice University 6100 Main Street Houston TX 77005 USA