Author(s):
Valente Nabais, J.M.
; Teixeira, Jorge Ginja
; Almeida, I.
Date: 2011
Persistent ID: http://hdl.handle.net/10174/3320
Origin: Repositório Científico da Universidade de Évora
Description
The aim of the work now reported is the development of low cost electrodes in the monolithic shape
without the need for a pos-production step with potential to be used in supercapacitors. The tested materials
were activated carbon fibres prepared and activated carbons made from coffee endocarp. The main
functional groups identified were quinone, lactone, Si–H, phenol, hydroxyl, carbonyl and ether for activated
carbon samples and amine, amide, pyrone, lactone, carbonyl and hydroxyl for activated carbon
fibres samples. The nanostructure of the materials is predominantly microporous but with a significant
variety of porosity development with BET surface area and pore volume given by as method range from
89 to 1050 m2 g 1 and 0.04 to 0.50 cm3 g 1, respectively. The electrochemical properties of the materials
were investigated using classic cyclic voltammetry, chronopotentiometry and electrochemical impedance
spectroscopy. The higher specific capacitance achieved was 176 F g 1.