1. Nano-Device Laboratory and Phonon Optimized Engineered Materials Center, Department of Electrical and Computer Engineering, University of California, Riverside, California 92521, United States
2. Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
3. Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588, United States
4. Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588, United States