Heat treatment of iron/carbon composites for energy storage: effect on
physicochemical and electrochemical properties

J. R. F. Gonçalves, C.F. Malfatti, E. Leal da Silva, G.R. Gonçalves, Miguel A. Schettino Jr., Jair C. C. Freitas and A. Cuña




Carbon materials are widely used as supercapacitor electrodes while iron oxides and other iron compounds are promising electrode materials due to its pseudocapacitive contribution. This work deals with the preparation and electrochemical characterization of iron/carbon composites for
supercapacitor electrode applications. The carbon precursor samples were prepared from a carbonization of babassu coconut endocarp, and the iron/carbon nanocomposites were obtained by
precipitation synthesis using iron salt, followed by a heat treatment at different temperatures. The electrochemical characterization of the samples show that, at low current density, the sample without iron compounds shows the higher electrical capacitance, up to 98 F g-1 in 2 M H2SO4. This good performance can be associated to a pseudocapacitive contribution of the oxygenated functional groups present in this sample. However, at higher current densities, the best electrochemical behaviour was achieved for the sample treated at 1000 °C. This good performance is may be associated to the Feº and Fe3C nanoparticles present in the sample which can enhance its
electrical conductivity. On the other hand, is no there clearly evidence of pseudocapacitive contribution of the iron particles. Future works will seek to improve the surface area of the materials with the aim to increase the double layer capacitance, and also to perform electrochemical studies using other electrolytes.

Published in: Renewable Energy & Power Quality Journal (RE&PQJ, Nº. 17)
Pages: 506-510 Date of Publication: 2019/07/15
ISSN: 2172-038X Date of Current Version:2019/04/10
REF: 359-19 Issue Date: July 2019
DOI:10.24084/repqj17.359 Publisher: EA4EPQ


Authors and affiliations

J. R. F. Gonçalves1, C.F. Malfatti1, E. Leal da Silva1,2, G.R. Gonçalves3, Miguel A. Schettino Jr.3, Jair
C. C. Freitas3, and A. Cuña2
1. LAPEC/PPGE3M, Universidade Federal do Rio Grande do Sul, Porto Alegre/RS (Brazil)
2. Area Fisicoquímica, DETEMA, Facultad de Química, Universidad de la República, Montevideo. (Uruguay)
3. Laboratory of Carbon and Ceramic Materials, Department of Physics, Federal University of Espírito Santo, Vitória, ES, Brazil

Key words

Energy storage, Supercapacitors, Pseudocapacitance, iron compounds, Biomass carbon materials


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