Hydrogen diffusion effects on the kinetics of the hydrogen electrode reaction Part II. Evaluation of kinetic parameters

Abstract

The present work proposes a methodology for the evaluation of the kinetic parameters of the hydrogen electrode reaction for the Tafel–Heyrovsky–Volmer mechanism from experimental results corresponding to the study of the hydrogen oxidation on a rotating disc electrode. It is based on the correlation of the experimental dependence j(η,ω) with a theoretical expression together with some constraints that involve the use of the equilibrium polarisation resistance, which reduces the number of adjustable parameters. This methodology was applied to the hydrogen oxidation reaction on a platinum electrode, which was studied in the range 900 ≤ ω/rpm ≤ 8100 and −0.05 ≤ η/V ≤ 0.40 in 0.5 M H₂SO₄. The results obtained have been discussed in the light of the theoretical treatment described in Part I of this work.