Low Cost Electrochemical Sensor for Simultaneous Detection and Estimation of Dihydroxybenzene Isomers

Abstract

An ionic liquid (IL) based pencil graphite electrode (PGE) sensor was electrochemically fabricated for hydroquinone (HQ), catechol (CC) and resorcinol (RS) simultaneous detection and estimation in aqueous media. PGE surface was modified by 1-hexylpyridinium hexafluorophosphate (HPHP) using cyclic voltammetry (CV). The modified surface was characterized by scanning electron microscope (SEM) and energy dispersive X-ray microanalysis (EDX). The modified electrode showed an excellent electro-analytical activity towards simultaneously HQ, CC and RS, at pH 6.8 in aqueous media. The scan rate effect was diffusion controlled and the concentration effect was linear with current. The limit of detection (LOD) for HQ, CC and RS was found to be 6.38 μmol L¹, 4.56 μmol L¹ and 19.6 μmol L¹, respectively. The sensitivity for HQ, CC and RS was found to be 448.49 μAmM -1 cm -2 , 627.35 μAmM -1 cm -2 and 146.10 μAmM −1 cm −2 , respectively, in a ternary mixture of dihydroxybenzene isomers (DHBIs). The cost of using PGE was lower than that of the conventional electrodes. isomers, ionic liquid, pencil graphite electrode and differential pulse voltammetry.