Understanding the electro-catalytic effect of benzene ring substitution on the electrochemical oxidation of aniline and its derivatives using BDD anode: Cyclic voltammetry, bulk electrolysis and theoretical calculations

Abstract

The use of boron doped diamond (BDD) films in environmental applications has been extensively proved. This electrocatalytic material produces higher concentrations of free‑hydroxyl radicals on its surface, favoring a complete mineralization of many organic pollutants. Although efficient degradation levels are achieved using BDD films, effects such as the chemical structure of the contaminant, waste by-products, oxidants produced, weak/strong surface interactions and bulk reactions influence the electro/chemical catalytic reactions as well as on the effectiveness of the process. In this frame, this study aims to investigate the effect of benzene ring substitution on the electrochemical oxidation of aniline and its derivatives using BDD anode. To do that, the electrochemical behavior of aniline, nitro and chloro‑aniline derivatives in aqueous solution on BDD anode using cyclic voltammetry and bulk electrolysis was examined as well as their environmental elimination was explained by quantum mechanics (QM) calculations. The results clearly allowed associating the experimental measurements to theoretical estimations to comprehend the catalytic relationship between the molecular electronic properties of aniline and its derivatives and their elimination from water.