Tungsten disulfide (WS2), a typical 2D layerd structure, has received much attention as a pseudocapacitive material because of its high theoretical specific capacity and excellent ion diffusion kinetics. However, WS2 has critical limits such as poor long-term cycling stability owing to its large volume expansion during cycling and low electrical conductivity. Therefore, to increase the high-rate performance and cycling stability for pseudocapacitors, well-dispersed WS2 nanoparticles embedded in carbon nanofibers (WS2-CNFs), including mesopores and S-doping, are prepared by hydrothermal synthesis and sulfurizaiton. These unique nanocomposite electrodes exhibit a high specific capacity (159.6 F g−1 at 10 mV s−1), excellent high-rate performance (81.3 F g−1 at 300 mV s−1), and long-term cycling stability (55.9% after 1,000 cycles at 100 mV s−1). The increased specific capacity is attributed to well-dispersed WS2 nanoparticles embedded in CNFs that the enlarge active area; the increased high-rate performance is contributed by reduced ion diffusion pathway due to mesoporous CNFs and improved electrical conductivity due to S-doped CNFs; the long-term cycling stability is attributed to the CNFs matrix including WS2 nanoparticles, which effectively prevent large volume expansion.

Abstract
1.서 론
2. 실험방법
3. 결과 및 고찰
4.결 론
References

• 성기욱(서울과학기술대학교 신소재공학과) | Ki-Wook Sung (Department of Materials Science and Engineering, Seoul National University of Science and Technology)
• 이정수(서울과학기술대학교 신소재공학과) | Jung Soo Lee (Department of Materials Science and Engineering, Seoul National University of Science and Technology)
• 이태근(서울과학기술대학교 신소재공학과) | Tae-Kum Lee (Department of Materials Science and Engineering, Seoul National University of Science and Technology) Corresponding author
• 안효진(서울과학기술대학교 신소재공학과) | Hyo-Jin Ahn (Department of Materials Science and Engineering, Seoul National University of Science and Technology) Corresponding author