分别以炭气凝胶(CAG),炭黑(CB)以及石墨(G)为导电剂与KOH活化法高比表面积活性炭(HSAC)制备复合电极,组装成双电层电容器,在(C2H5)4NBF4/丙烯碳酸盐电解液体系中进行交流阻抗测试分析.应用动力学及电子传递控制的等效电路模型对各电极的实验阻抗数据进行拟合得到相应的模型参数,串联溶液电阻Rs、极化电阻Rp、能斯特边界层厚度δ及平均孔内离子扩散系数D.结果表明,炭气凝胶复合电极的孔内离子扩散系数D最高,极化电阻Rp与炭黑复合电极接近.炭气凝胶电极的内阻为各电极中最低并且具有最高的比电容.
Carbon aerogel (CAG), carbon black (CB), and graphite (G) were added to a high surface area activated carbon (HSAC), prepared by KOH activation, to form composites for use as electrodes of electrochemical capacitors(ECs). The performance of the ECs using these electrodes in (C2H5)4NBF4/propylene carbonate electrolyte were ana lyzed and compared by an electrochemical impedance spectrum (EIS). An equivalent circuit model with mixed kinetic and charge transfer control was assumed and a Marquardt fit procedure was applied to the EIS data, from which model parameters, such as, series solution resistance, Rs, polarization resistance, Rp, Nernst diffusion layer thickness, δ, and average value of the diffusion coefficients of electrolyte ions, D, were extracted and compared for CAG-, CB-, and Gbased composites. It was found that the ECs using CAG had the highest D values and a comparable Rp value with CB.The CAG-based composite had the lowest resistance and highest capacitance at the same frequencies among the three types of composites investigated.
参考文献
[1] | R. Kotz;M. Carlen .Principles and applications of electrochemical capacitors[J].Electrochimica Acta,2000(15/16):2483-2498. |
[2] | Burke A .Ultracapacitors:why,how,and where is the technology[J].Journal of Power Sources,2000,91:37-50. |
[3] | Qu Deyang;Shi Hang .Studies of activated carbons used in double-layer capacitors[J].Journal of Power Sources,1998,74:99-107. |
[4] | Toupin M;Bélanger D;Hill I R et al.Performance of experimental carbon blacks in aqueous supercapacitors[J].Journal of Power Sources,2005,140:203-210. |
[5] | D. Lozano-Castello;D. Cazorla-Amoros;A. Linares-Solano .Influence of pore structure and surface chemistry on electric double layer capacitance in non-aqueous electrolyte[J].Carbon: An International Journal Sponsored by the American Carbon Society,2003(9):1765-1775. |
[6] | Songhun Yoon;Jong H. Jang;Bok H. Ka;Seung M. Oh .Complex capacitance analysis on rate capability of electric-double layer capacitor (EDLC) electrodes of different thickness[J].Electrochimica Acta,2005(11):2255-2262. |
[7] | L. Bonnefoip. Simon;J.F. Fauvarque;C. Sarrazin .Electrode optimisation for carbon power supercapacitors[J].Journal of Power Sources,1999(1):37-42. |
[8] | S. Toth;M. Fuele;M. Veres;J.R. Selman;D. Arcon;I. Pocsik;M. Koos .Influence of amorphous carbon nano-clusters on the capacity of carbon black electrodes[J].Thin Solid Films: An International Journal on the Science and Technology of Thin and Thick Films,2005(1/2):207-210. |
[9] | Wu N L;Wang S Y .Conductivity percolation in carbon-carbon supercapacitor electrodes[J].Journal of Power Sources,2002,110:233-236. |
[10] | 刘希邈,詹亮,滕娜,杨登莲,曾小春,张睿,凌立成.超级电容器用沥青焦基活性炭的制备及其电化学性能[J].新型炭材料,2006(01):48-53. |
[11] | RUI ZHANG;YONGGEN LUE;QINGHAN MENG;LIANG ZHAN;GANGPING WU;KAIXI LI;LICHENG LING .On Porosity of Carbon Aerogels from Sol-Gel Polymerization of Phenolic Novolak and Furfural[J].Journal of porous materials,2003(1):57-68. |
[12] | 张睿,梁晓怿,詹亮,李开喜,吕春祥,凌立成.酚醛-糠醛基炭气凝胶的合成和表征[J].新型炭材料,2002(04):23-28. |
[13] | Scully J R;Silverman D C;Kendig M W.Electrochemical Impedance:Analysis and Interpretation[M].ASTM,1993 |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%