Charge Transfer Resistance in the Hydrogen Evolution Reaction under the Conditions of Temkin Isotherm

The charge-transfer resistance R₁ as a function of the electrode potential Е for the hydrogen evolution reaction passing by the Volmer–Heyrovsky mechanism involving atomic hydrogen adsorbed according to Temkin isotherm is studied. For a quasiequilibrium Volmer reaction, logR₁,E-curves have a minimum and a maximum. With the increasing of the surface nonuniformity factor f the minimum has been shifted toward lower electrode potentials, the minimum region in the voltammogram is widened. The half-width of the minimum region allowed determining the f value. At the lowest and highest values of the surface coverage, the logR₁,E-dependence demonstrated the same regularities as the Langmuir isotherm.