Title :
Treatment of Reticulated Vitreous Carbon by Dielectric Barrier Discharge Plasma for Electrodes Production
Author :
Goncalves da Silva, Leide Lili ; Ferreira, Luiz Gustavo ; Lima Santos, Alberto ; Cocchieri Botelho, Edson ; Toth, Akos ; Kostov, Konstantin Georgiev
Author_Institution :
FATEC, Pindamonhangaba, Brazil
Abstract :
This paper deals with the surface modification of reticulated vitreous carbon (RVC) by dielectric barrier discharge (DBD) for electrodes production. RVC samples were exposed to air-DBD plasma for 5.0 and 10.0 min. Following the treatment, the specimens were characterized by scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), contact angle measurements, and electrochemical analyses [cyclic voltammetry (CV)]. The SEM images show an alteration of the RVC surface morphology because of the surface etching during the DBD processing. This finding is in agreement with the enhanced specific electrochemical surface area of RVC electrodes, which is related to an increase of its surface roughness. In addition, a slight increase of the oxygen content on the surface was confirmed by XPS analysis. Therefore, the RVC surface became more hydrophilic as detected by water contact angle measurements. For corroborating this statement, a solid monolithic vitreous carbon was used for this test. An increase in the anodic charge of the RVC electrodes due to the surface oxidation was also observed. Raman spectra showed insignificant changes in the material crystalline structure.
Keywords :
Raman spectra; X-ray photoelectron spectra; carbon; contact angle; crystal structure; electrochemical electrodes; oxidation; scanning electron microscopy; sputter etching; surface morphology; surface roughness; voltammetry (chemical analysis); C; CV; Raman spectroscopy; SEM; X-ray photoelectron spectroscopy; air-DBD plasma; anodic charge; cyclic voltammetry; dielectric barrier discharge plasma; electrochemical analysis; electrochemical surface area; electrode production; hydrophilicity; material crystalline structure; oxygen content; reticulated vitreous carbon electrodes; scanning electron microscopy; solid monolithic vitreous carbon; surface etching; surface modification; surface morphology; surface oxidation; surface roughness; time 10.0 min; time 5.0 min; water contact angle measurements; Discharges (electric); Electrodes; Plasmas; Rough surfaces; Surface morphology; Surface roughness; Surface treatment; Atmospheric plasma treatment; dielectric barrier discharge (DBD); electrodes; reticulated vitreous carbon (RVC);
Journal_Title :
Plasma Science, IEEE Transactions on
DOI :
10.1109/TPS.2013.2278239