1. School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
2. Department of Mechanical Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
3. Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
4. Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Republic of Korea
5. Center for Human-Oriented Triboelectric Energy Harvesting, Yonsei University, Seoul 03722, Republic of Korea