Mechanism of inhibition of electrode reactions at high surface coverages - II

Abstract

The inhibition of Cu²⁺, Cd²⁺ and Zn²⁺ discharge reactions was studied in the presence of C₄-C₆ alcohols, phenol, benzyl alcohol and cyclohexanol (SAS) in 0.5 M Na₂SO₄ + 1 mM H₂SO₄ supporting electrolyte. It is found from the results that at high surface coverages by SAS, the inhibition is due to "sieve effect" which is different from that at low coverages. The true standard rate constant is proportional to exp[(- N ΔγA_i)/(RT)] where ΔγA_i) is the extra energy (in the form of work) that must be done in order to create a free area required for a discharge reaction.