Electrochemical detection of sulphide in water/seawater using nanostructured carbon-epoxy composite electrodes

In this study, the performance of a carbon nanofibre-epoxy composite (CNF) electrode was compared with that of a boron-doped diamond (BDD) electrode for the voltammetric/amperometric direct detection of sulphide in water and seawater by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square-wave voltammetry (SWV). Both electrodes allowed direct detection of sulphides in aqueous solutions, and carbon nanofibres exhibited a catalytic effect towards sulphide oxidation, which led to the best sensitivity. The best electroanalytical parameters were achieved using pulsed voltammetric techniques, with optimized square-wave voltammetry achieving the best sensitivity of 347.899 mu A mM(-1) for sulphide detection. However, the chronoamperometry (CA) results achieved with real water without any supporting electrolyte were also very promising for the practical use of CNF electrodes for the infield direct detection of sulphide in water and seawater.