The charge transfer resistance in the hydrogen evolution reaction with the Temkin adsorption isotherm

Abstract

The charge transfer resistance R1 versus overpotential  relations were studied for the hydrogen evolution reaction that proceeds through the Volmer–Heyrovsky mechanism with adsorbed hydrogen atoms obeying the Temkin isotherm. In the case k10, k-10>>k20, k-20 (where ki0 are the rate constants of the steps at  = 0), logR1- curve has a mini- mum and a maximum. As the surface heterogeneity factor f increases the minimum shifts to lower electrode potentials and the region of minimum becomes wider. The f value can be estimated from the full width at half minimum. At very low and very high coverage, logR1- curves show the same behavior as that for the Langmuir isotherm