Impedance of Two-Stage Adsorptive Oxidation with Quadratic Dependence of Activation Energy on Potential on a Boron-Doped Diamond Anode

摘要

Experimental impedance data on the benzene oxidation on a diamond anode highly doped with boron are considered. The frequency-polarization analysis of impedance of the anodic charge-transfer reaction involving two adsorption stages with partial charge transfer (disregarding the diffusion stage) is accomplished. The considered case corresponds to the linear dependence of reaction stage rates on the surface coverage, the linear dependence of the effective number of electrons transferred in each stage on the potential and, hence, the quadratic dependence of the activation energy of adsorption on the potential. The Grafov-Pekar method of equivalent multipole is used for explaining the interrelation between model parameters and the shape of experimental curves. The use of a boron-doped diamond electrode makes it possible to experimentally confirm the very fine effects of adsorptive oxidation of the organic substance.