1. Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, United States
2. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
3. Department of Chemistry, University of California, Berkeley, California 94720, United States
4. Kavli Energy Nanoscience Institute at Berkeley, Berkeley, California 94720, United States
5. Department of Energy Science and Centre for Artificial Atoms, Sungkyunkwan University, Natural Sciences Campus, Seobu-ro 2066, Jangan-gu, Suwon 16419, Gyeonggi-do, Republic of Korea
6. Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
7. Materials Science and Engineering, University of California, Berkeley, California 94720, United States