Electrooxidative Behavior of Arylazo Pyridone Dyes and Their Inclusion Complexes on Gold Electrode in 0.1 M NaOH

Abstract

The electrochemical behavior of six arylazo pyridone dyes classified to the substituents present at the phenylazo and 2-pyridone moiety and their 1:1 inclusion complexes with (2-hydroxypropyl)-beta-cyclodextrin was studied using cyclic and square wave voltammetry in 0.1 M NaOH on a gold electrode. The formation of the inclusion complexes of the dyes was confirmed using UV-Vis and FTIR spectroscopy measurements. Among the studied dyes, according to potentiodynamic measurements, the most active is the dye 1. The inclusion complexes of the dyes exhibited improved electrochemical activity in comparison to the pure dyes. The results obtained by square wave voltammetry show the apparent activity of the dyes with a methoxy group as a substituent at the phenylazo moiety and ethyl and hydroxyethyl groups in the 2-pyridone moiety, and their inclusion complexes. The electrooxidation mechanism of the investigated arylazo pyridone dyes was also proposed.