1. Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
2. Department of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
3. Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
4. Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
5. Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States