방진호
2019-11-06T00:09:02Z
2019-11-06T00:09:02Z
2019-05
ELECTROCHIMICA ACTA, v. 304, Page. 210-220
0013-4686
1873-3859
https://www.sciencedirect.com/science/article/pii/S0013468619303913?via%3Dihub
https://repository.hanyang.ac.kr/handle/20.500.11754/111891
For high performance of electrical double layer capacitors (EDLCs), a high specific surface area (SSA) and N-doping level, and small particle size of carbonaceous materials, have been believed to be crucial factors. However, there have been few reports on simultaneous study of the structure-properties relations of carbons and the electrochemical performances of EDLCs. Herein, we report the relationship between the structural properties of carbons, such as the SSA, N-doping, and particle size, and the electrochemical properties of EDLCs by using a series of well-defined carbons. Monodisperse and sizetunable resorcinol-formaldehyde carbon (RFC) spheres were synthesized and activated by hot CO2 treatment to increase the SSA up to 3958 m(2)/g (RFC_C390 sample). When the specific capacitances of the RFC spheres were plotted in terms of their SSAs, an almost perfect correlation (R-2 = 0.99) was observed, which confirmed the linear relationship between the specific capacitance and the SSA. In addition, N-doped melanin C (MC) spheres were synthesized and subsequently activated for N-doping effect. Activated MC (MC_C130), which exhibited similar SSA (2618 m(2)/g) and size (301 nm) but a different N-doping level (3.1%) compared with those (2793 m(2)/g, 312 nm, and 1.3%, respectively) of the activated RFC spheres (RFC_C120), displayed higher specific capacitance (288 F/g), capacitance retention (64%), and long term stability over 5000 cycles (93%) compared with those (260 F/g, 58%, and 90%, respectively) of the RFC counterparts. To observe the particle size effect, different sizes (98, 280, and 579 nm) of RFC spheres with similar SSAs (3981, 3958, and 3898 m(2)/g, respectively) and pore size distributions were prepared, such that the smallest RFC revealed the best EDLC performance in terms of specific capacitance (360 F/g), capacitance retention (70%), and long term stability over 5000 cycles (98%), all of which could be compared with the values reported in the literature. Furthermore, all of the Carbon samples were analyzed by using electrochemical impedance spectroscopy for confirming the structure-properties relations of carbon spheres with the electrochemical performances of EDLCs. (C) 2019 Elsevier Ltd. All rights reserved.
This work was supported by the Basic Science Research Program of the National Research Foundation of Korea (NRF-2016R1D1A1B03930258 and NRF-2018R1A6A1A03024231).
en
PERGAMON-ELSEVIER SCIENCE LTD
Carbon sphere
Electrical double layer capacitors (EDLCs)
Surface area effect
Size effect
N-doping effect
Study of the structure-properties relations of carbon spheres affecting electrochemical performances of EDLCs
Article
304
10.1016/j.electacta.2019.02.121
210-220
ELECTROCHIMICA ACTA
Kim, Hee Soo
Abbas, Muhammad Awais
Kang, Min Seok
Kyung, Hyuna
Bang, Jin Ho
Yoo, Won Cheol
2019001730
S
GRADUATE SCHOOL[S]
DEPARTMENT OF BIONANOTECHNOLOGY
jbang
A-4850-2016