Sensitive detection of heavy metal ions: An electrochemical approach

Polyaniline (PANI) is one of conducting polymers (CPs) which has been used widely in various fields of applications. The low cost monomer, red/ox reversibility, existence of various oxidation states, electrical & optical activity, environmental stability, etc. are the characteristic reasons for it. Herein, we report the electrochemically synthesized PANI and its composite with single-walled carbon nanotube (SWNTs) — PANI/SWNTs. The effects of inculcation of SWNTs were studied using the electrochemical properties of PANI and PANI/SWNTs composites, using the electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) for the electro active natures of both. For the study of optical absorption UV–visible (UV–Vis) spectroscopy was used and for morphology the field effect scanning electron mictroscopy (FESEM) was used. The composite PANI/SWNTs exhibited a good electroactive nature and therefore was opted as a sensing platform for the detection of nickel ions. For the selectivity inculcation of the nickel ions, the chelating ligand viz. dimethylglyoxime (DMG) was used for the modification of the composite.