Physical adsorption of N,N′-diphenyl-p-phenylenediamine onto carbon particles: Application to the detection of sulfide

The derivatisation of carbon powder by physical adsorption of N,N'-diphenyl-p-phenylenediamine (DPPD) onto the surface of graphite particles (1-2 microm diameter) results in usefully functionalised carbon. The derivatised carbon powders have been studied using cyclic voltammetry by (i) abrasive immobilisation of the powder onto a basal plane pyrolytic graphite electrode (bppg) and (ii) by the manufacture of carbon-epoxy electrodes containing the derivatised carbon. The electrochemical response of the DPPD modified carbon has been examined in the presence of sulfide and possible reactions identified for the behaviour of each electrode substrate. The analytical application of the carbon-epoxy electrode for the sensing of sulfide is reported.