A study of redox-active Nafion® modified electrodes for trace metal detection by anodic stripping voltammetry

• Main Author: Guatato, Toni Beth F.
• Format: text
• Language: English
• Published: Animo Repository 2014
• Subjects: Electrodes
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4642
• Institution: De La Salle University

Chemically modified electodes were fabricated by depositing tris (2,2-bipyridyl) ruthenium (II) dichloride hexahydrate doped Nafion® thin films on indium tin oxide coated glass substrates via the dip coating method. The Nafion and ruthenium complex concentrations were varied to optimize the sensitivity of the modified electrodes in detecting cadmium and lead. The surface morphology of the deposited film was characterized by scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX). The presence of the heavy metals in a 0.1 M NaCl supporting electrolyte solution was determined through the marked reduction potentials in the voltammograms obtained from the anodic stripping voltammetry (ASV) runs. The optimum Nafion volume concentration in the film was 0.4% which gave an average film thickness of 217.90 nm. The optimum mediator concentration is 5 mg per 1mL of Nafion. The minimum concentration detected for lead was 0.002 µg/mL and for cadmium was 0.9 µg/mL. The calibration curves obtained for both heavy metals show a linear relationship with an R2 value equal to 0.9514 for lead and 0.9832 for cadmium.