Sensor de pasta de nanotubos de carbono modificado com filme de bismuto para determinação de íons metálicos em etanol combustível

Abstract

In the present study an anodic stripping voltammetric method using a bismuth film modified carbon nanotubes paste electrode for simultaneous determination of metals Zn 2+ , Cd 2+ and Pb 2+ in ethanol fuel is described. The metallic ions were preconcentrated on the bismuth film in the time and deposition potential of 500 s and -1.2 V and the stripping step was carried out by square wave voltammetry (frequency of 15 Hz, pulse amplitude of 25 mV and potential step of 5 mV). Acetate buffer at 0.1 mol L -1 concentration and pH 4.5 was used as support electrolyte.