EDTA Modified PANI/GO Composite Based Detection of Hg (II) Ions

Abstract

Electrochemical recognition of Hg (II) ions utilizing EDTA modified polyaniline (PANI)/Graphene Oxide (GO) composite is reported in the present communication. Graphene Oxide (GO) synthesis was carried out by a modified Hummer’s method. Electrochemical characterizations, namely cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), were performed before and after modification of the composite. The topographies of the PANI/GO composite and EDTA_PANI/GO electrodes were studied using AFM. Roughness parameter values were compared for confirmation of surface modification. Fourier transform infrared spectroscopy (FTIR) was utilized for the compositional analysis of PANI/GO and EDTA_PANI/GO electrodes. The EDTA_PANI/GO composite exhibits sensitivity toward Hg (II) ions when probed using the differential pulse stripping voltammetry (DPSV) technique with a lower detection limit of 2 ppb. EDTA modified SS_PANI/GO composite (PANI/GO composite deposited on a stainless-steel substrate) showed superior sensitivity in the detection of Hg (II) ions. The sensitivity was observed to extend to 1 ppb, which is smaller than the maximum contaminant level (MCL) endorsed by the Environment Protection Agency (EPA, United States).