In this study, N/S co-doped carbon felt (N/S-CF) was prepared and characterized as an electrode material for electric double-layer capacitors (EDLCs). A commercial carbon felt (CF) was immersed in an aqueous solution of thiourea and then thermally treated at 800 oC under an inert atmosphere. The prepared N/S-CF showed a large specific surface area with hierarchical pore structures. The electrochemical performance of the N/S-CF-based electrode was evaluated using both 3- electrode and 2-electrode systems. In the 3-electrode system, the N/S-CF-based electrode showed a good specific capacitance of 177 F/g at 1 A/g and a good rate capability of 41% at 20 A/g. In the 2-electrode system (symmetric capacitor), the freestanding N/S-CF-based electrode showed a specific capacitance of 275 mF/cm2 at 2 mA/cm2, a rate capability of 62.5 % at 100 mA/cm2, a specific power density of ~ 25,000 mW/cm2 at an energy density of 23.9 mWh/cm2, and a cycling stability of ~ 100 % at 100 mA/cm2 after 20,000 cycles. These results indicate the N/S co-doped carbon felts can be a promising candidate as a new electrode material in a symmetric capacitor.

Abstract
1. 서 론
2. 실험 및 분석 방법
3. 결과 및 고찰
4. 결 론
Acknowledgement
References

• 이병민(충남대학교 고분자공학과) | Byoung-Min Lee (Department of Polymer Science and Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of Korea)
• 윤제문(동의대학교 신소재공학부) | Je Moon Yun (Division of Advanced Materials Engineering, Dong-Eui University, 178 Eomgwang-ro, Busanjin-gu, Busan 47340, Republic of Korea) Corresponding author
• 최재학(충남대학교 고분자공학과) | Jae-Hak Choi (Department of Polymer Science and Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of Korea) Corresponding author