Stripping Voltammetry with Nanomaterials-based Electrode in the Environmental Analysis of Trace Concentrations of Tin

Abstract

A method for the voltammetric determination of tin using a multiwall carbon nanotubes/spherical glassy carbon (CNTs/SGC) electrode is described. The new procedure is based on the adsorptive accumulation of the Sn(II)-cupferron complex on a CNTs/SGC electrode modified with a lead film, followed by electrochemical reduction of the adsorbed species. The optimal experimental conditions include the use of 0.10 mol L−1 acetate buffer (pH 5.7), 4.0×10−4 M cupferron and 1.0×10−4 M Pb(II). The peak current is proportional to the concentration of Sn(II) over the range of 1.0×10−9–1.0×10−7 M and the detection limit is 3.1×10−10 M for a 95 s accumulation time. The proposed method was used to determine tin in real samples and certified reference materials.