Deconvolution of Cyclic Voltammograms in the Hydrogen Region of the Platinum-Black Electrodes with the Asymmetric Double Sigmoid Function

Ångström Laboratory, Inorganic Chemistry, Uppsala University, Uppsala, Sweden

*Corresponding Author: Romulus V Bucur, Ångström Laboratory, Inorganic Chemistry, Uppsala University, Uppsala, Sweden; Email: [email protected]

Received Date: March 11, 2024

Publication Date: May 07, 2024

Citation: Bucur RV. (2024). Deconvolution of Cyclic Voltammograms in the Hydrogen Region of the Platinum-Black Electrodes with the Asymmetric Double Sigmoid Function. Material Science. 6(1):26.

Copyright: Bucur RV. © (2024). 

ABSTRACT

The deconvolution of the cyclic voltammograms (CVs) using an asymmetric double sigmoid function was tested in the hydrogen region of a model platinum-black electrode to extract and quantitatively evaluate the peaks’ information. CVs were recorded in 1M HClO₄ solution, at T = 298 K, for three different values of the minimum scanning potential near the electrode equilibrium potential. The fine structure of CVs is determined by the hydrogen evolution reaction (HER/adsorption) and the hydrogen oxidation reaction (HOR/desorption) that take place at the surface's strong(s) and weak(w) adsorption sites. HER occurs mainly on the w-sites, whose equivalent surface area makes up the electrochemical active surface area (EASA), while that corresponding to the s-sites is inactive. The surface area calculated from the charges of CVs curves yields the electrode’s total surface area with overestimated values of about 30% compared with EASA. In principle, the efficiency of the HER/HOR could be improved by diminishing the density of the strong adsorption sites and/or increasing that of the weak adsorption sites

Keywords: Pt-black, H–region, Cyclic voltammograms, Asymmetric double sigmoid function, Deconvolution, HER/HOR