Anodic stripping voltammetric detection of mercury(ii) using Au-PEDOT modified carbon paste electrode

Abstract

Gold-poly(3,4-)ethylenedioxythiophene (Au-PEDOT) was synthesized using a novel interfacial synthetic route. Using Au-PEDOT, carbon paste electrodes were fabricated and mercury detection was attempted exploiting gold–mercury interaction chemistry. Anodic stripping voltammetric analysis shows excellent sensitivity for micromolar level detection of mercury (LOD = 5 μM). In the amperometric detection of mercury, electrode fouling is a major problem since the memory effect cannot easily be removed. Hence, colorimetric/fluorescence techniques mostly dominate the field, using gold nanoparticle probes for the detection of mercury. Au-PEDOT carbon composite film electrodes showed excellent repeatable measurements avoiding the memory effect while detecting the mercury using anodic stripping voltammetry. As a preliminary investigation, the present carbon composite has been successfully demonstrated for mercury detection in tap water.