EDTA-modified PANI/SWNTs nanocomposite for differential pulse voltammetry based determination of Cu(II) ions

Abstract

Differential pulse voltammetry (DPV) based electrochemical sensor dedicated for the determination of Cu(II) ion concentration is reported in this research. Sensor was based on electrochemically synthesized polyaniline (PANI) and single walled carbon nanotubes (SWNTs) nanocomposite (PANI/SWNTs), which was additionally functionalized by ethylenediaminetetraacetic acid (EDTA) in order to get structure (EDTA-PANI/SWNTs) with advanced selectivity towards Cu(II) ion. Synthesis of PANI/SWNTs nanocomposite was performed by potential cycling, dodecyl benzene sulphonic acid sodium salt (DBSA) was used as a surfactant during the synthesis of PANI/SWNTs nanocomposite to get a uniform suspension of SWNTs at room temperature. In the next step, PANI/SWNTs nanocomposite was further modified by the EDTA solution containing 1-ethyl-3(3-(dimethylamino)propyl)-carbodiimide (EDC) as activating agent, which is activating carboxyl groups, utilizing dip coating technique at room temperature. Differential pulse voltammetry (DPV) technique was applied for the electrochemical detection of Cu(II) ion. DPV based response of EDTA-PANI/SWNTs structure towards Cu(II) ion was investigated. Analytical signals reveal that EDTA-PANI/SWNTs structure is suitable for selective determination of Cu(II) ion in the presence of interfering Pb(II), Cd(II), Ni(II) and Co(II) ions.