Abstract
The obtainment of a high specific surface area (SSA) without disrupting the conductivity of carbon is very challenging. Herein, an as-synthesized polyamic acid (PAA) derivative dissolved in 1,4-dioxane solvent was freeze dried to prepare a PAA cryogel, which allowed homogenous shrinkage of the texture and a high carbon yield upon carbonization. This work presents the successful template-free preparation of a high-surface area microporous carbon with a unique microcellular structure by simple carbonization treatment of a PAA cryogel. Upon increasing the carbonization temperature, the N content decreased, which was unfavorable for capacitance, but simultaneously, both the surface area and the crystallinity increased, which was beneficial in increasing the capacitance; these results are indicative of an interesting trade-off relationship between surface area, conductivity, and the N content of the carbon. In particular, C-PAA(1000) prepared by carbonization at 1000°C from the PAA cryogel showed a high porosity of approximately 90.8% and a remarkably high SSA of 2038 m2g-1 along with high crystallinity and effective N doping favorable for good conductivity; this material thus illustrates a high specific capacitance of 248 Fg-1 at 0.5 Ag-1 and excellent stability in inorganic electrolyte.
Original language | English |
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Pages (from-to) | 278-287 |
Number of pages | 10 |
Journal | Energy Technology |
Volume | 4 |
Issue number | 2 |
DOIs | |
State | Published - 1 Feb 2016 |
Bibliographical note
Publisher Copyright:© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Keywords
- Carbon
- Cryogels
- Hierarchical structures
- Microporous materials
- Supercapacitance