Amperometric determination of thiourea in alkaline media on a copper oxide–copper electrode

A copper oxide–copper electrode was tested in alkaline media for the anodic electrochemical detection of thiourea (TU). The correlation between the history of the electrode and potential range for optimum sensing of the particular susceptible species was analysed by electrochemical and surface layer techniques. The chemical composition and morphology of surface layers were examined using the SEM/EDX technique. Electrochemical data were obtained by cyclic voltammetry (CV) and chronoamperometry (CA). The linear calibration plots for an amperometric detection of TU in a delimited potential range, using CV and CA, were obtained for the 1–8 mM concentration range. Some considerations on the correlation between TU, electrode formation and polarization conditions are proposed. A copper oxide–copper electrode can be used as an inexpensive alternative for amperometric determination of TU in alkaline media without fouling the electrode surface.