Electrooxidation of thiourea and its square-wave voltammetric determination using pencil graphite electrode

Abstract

The electrochemical properties of thiourea (TU) were investigated in pH range 2.0–12.0 by cyclic and square-wave voltammetry. The compound was irreversibly oxidized at a pencil graphite electrode in one or two oxidation steps which are pH-dependent. Based on the voltammetric peak for the second oxidation process of TU in phosphate buffer at pH 12.0, a square-wave voltammetric method was proposed for the determination of the compound in the range 6.3–30μm, with a detection limit of 1.29μm. The applicability to direct assays of wastewaters was also tested.

Keywords

• cyclic voltammetry
• pencil graphite electrode
• square-wave voltammetry
• thiourea
• wastewater