화학공학소재연구정보센터
Journal of Electroanalytical Chemistry, Vol.748, 61-69, 2015
Criteria for the selection of the scan rate in the evaluation of the kinetic parameters of the hydrogen oxidation reaction by a potentiodynamic sweep
The use of the current density values obtained from a voltammetric sweep at a slow scan rate j(vs)(eta) in place of those of a steady state polarization j(ss)(eta) for the determination of the kinetic parameters of the hydrogen oxidation reaction (hor) on a rotating disk electrode was analyzed. Three sets of kinetic parameters similar to those evaluated previously for the noble metals Pt, Jr and Rh, used as electrocatalysts for this reaction, at three different rotation rates omega (100, 3600 and 10,000 rpm) and four different scan rates v(s) (10(-4), 10(-3), 10(-2) and 5 x 10(-2) V s(-1)) were selected for this study. The determination of the hydrogen electrode reaction (HER) polarization resistance, around the equilibrium condition, was also investigated. Finally, the conditions in which the approximation j(vs)(eta) congruent to j(ss)(eta) can be considered valid were established for both, the polarization plot and the polarization resistance and practical criteria were established. (C) 2015 Elsevier B.V. All rights reserved.