1. Division of Energy and Environment
2. Graduate School at Shenzhen
3. Tsinghua University
4. Shenzhen 518055
5. China
6. State Key Laboratory of Electronic Thin Films and Integrated Devices
7. University of Electronic Science and Technology of China
8. Chengdu 610054
9. School of Materials Science and Engineering
10. Georgia Institute of Technology
11. Atlanta
12. USA
13. School of Physical & Mathematical Sciences
14. Nanyang Technological University
15. Singapore