Resumo (PT):
Abstract (EN):
A new electrochemical cell design suitable for the electrochemical impedance spectroscopy (EIS)
studies of chlorine evolution on Dimensionally Stable Anodes (DSA®) has been developed. Despite
being considered a powerful tool, EIS has rarely been used to study the kinetics of chlorine evolution
at DSA anodes. Cell designs in the open literature are unsuitable for the EIS analysis at high DSA
anode current densities for chlorine evolution because they allow gas accumulation at the electrode
surface. Using the new cell, the impedance spectra of the DSA anode during chlorine evolution at high
sodium chloride concentration (5 mol dm−3 NaCl) and high current densities (up to 140 mA cm−2
)
were recorded. Additionally, polarization curves and voltammograms were obtained showing little or
no noise. EIS and polarization curves evidence the role of the adsorption step in the chlorine evolution
reaction, compatible with the Volmer-Heyrovsky and Volmer-Tafel mechanisms.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
8