An electrical double-layer capacitor (EDLC) is based on the physical adsorption/desorption of electrolyte ions onto the surface of electrodes. Due to its high surface area and other properties, such as electrochemical stability and high electrical conductivity, carbon materials are the most widely used materials for EDLC electrodes. In this work, we study an activated carbon felt obtained from sheep wool felt (ACF'f) as a supercapacitor electrode. The ACF'f was characterized by elemental analysis, scanning electron microscopy (SEM), textural analysis, and X-ray photoelectron spectroscopy (XPS). The electrochemical behaviour of the ACF'f was tested in a two-electrode Swagelok ®-type, using acidic and basic aqueous electrolytes. At low current densities, the maximum specific capacitance determined from the charge-discharge curves were 163 F•g −1 and 152 F•g −1 , in acidic and basic electrolytes, respectively. The capacitance retention at higher current densities was better in acidic electrolyte while, for both electrolytes, the voltammogram of the sample presents a typical capacitive behaviour, being in accordance with the electrochemical results.

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Carbon fibers and activated carbon fibers are materials of high industrial interest. When presented as a felt, its use becomes easier and more practical. This work aims to study the conditions for obtaining and characterizing an activated carbon felt, using sheep wool as a precursor. The wool felt was oxidized, carbonized in nitrogen atmosphere and activated in water vapor. The working temperatures were selected through thermogravimetric analysis. The products and intermediates were characterized through thermogravimetric analysis, infrared spectroscopy, scanning electron microscopy, Raman spectroscopy and nitrogen adsorption-desorption. The products were assessed as potential sorbents for methane-carbon dioxide separation by adsorption kinetics measurements at different pressures. Results revealed a high influence of the carbonization temperature on the physicochemical and textural properties of the products. The adsorption kinetics and capacities of the gases showed that selectivities in separation were related to both felt carbonization temperature and gas pressure. This work revealed that activated carbon wool felts are a good alternative to synthetic fibers felt and they can be used for methane/carbon dioxide separation.

Carbon material is the largest material used as electrode on advanced energy storage devices. The modern lifestyle requires more energy, consequently, more smart energy use and efficient devices are needed. The constant evolution of materials technologies looking for green material and renewable raw material, that have minimal impact on the environment, is one of the most important subjects studied in recent years. The scientific and industry community are paying more attention to new forms of carbon such as nanotubes, graphene, and activated carbon fiber. The purpose of this work is to convert human hair into a hollow carbon filament to be used as a supercapacitor electrode. The human hair needs 3 stages to be converted into carbon filament: textile manufacture, oxidation, and carbonization. The electrochemical behavior was analyzed in a threeelectrode electrochemical cell system with 2 M of H 2 SO 4 electrolyte medium. The behavior of the electrode was characterized electrochemically by galvanostatic charge/discharge curves, cyclic voltammetry, and electrochemical impedance spectroscopy, showing 163 F g -1 of a maximum value of specific capacitance.