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Advances in Materials Science and Engineering
Volume 2017, Article ID 3625414, 8 pages
https://doi.org/10.1155/2017/3625414
Research Article

Activated Carbon Fiber Monoliths as Supercapacitor Electrodes

1Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas (CSIC), Sor Juana Inés de la Cruz 3, Cantoblanco, 28049 Madrid, Spain
2Centro Nacional de Investigaciones Metalúrgicas (CENIM), CSIC, Avda. Gregorio del Amo 8, 28040 Madrid, Spain
3Inorganic Chemistry Department, University of Alicante, San Vicente del Raspeig S/N, 03080 Alicante, Spain

Correspondence should be addressed to Mirko Kunowsky; se.au@ykswonuk

Received 31 March 2017; Accepted 30 May 2017; Published 28 June 2017

Academic Editor: Germà Garcia-Belmonte

Copyright © 2017 Gelines Moreno-Fernandez et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Activated carbon fibers (ACF) are interesting candidates for electrodes in electrochemical energy storage devices; however, one major drawback for practical application is their low density. In the present work, monoliths were synthesized from two different ACFs, reaching 3 times higher densities than the original ACFs’ apparent densities. The porosity of the monoliths was only slightly decreased with respect to the pristine ACFs, the employed PVDC binder developing additional porosity upon carbonization. The ACF monoliths are essentially microporous and reach BET surface areas of up to 1838 m2 g−1. SEM analysis reveals that the ACFs are well embedded into the monolith structure and that their length was significantly reduced due to the monolith preparation process. The carbonized monoliths were studied as supercapacitor electrodes in two- and three-electrode cells having 2 M H2SO4 as electrolyte. Maximum capacitances of around 200 F g−1 were reached. The results confirm that the capacitance of the bisulfate anions essentially originates from the double layer, while hydronium cations contribute with a mixture of both, double layer capacitance and pseudocapacitance.