1. Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
2. Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
3. Division of Nanomaterials and Energy Conversion, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China