A novel sensitive electrochemical sensor for lead ion based on three-dimensional graphene/sodium dodecyl benzene sulfonate hemimicelle nanocomposites

For the first time, a novel lead ion electrochemical sensor based on three-dimensional grapheme foam/sodium dodecyl benzene sulfonate hemimicelle (3D GF/SDBS HM) nanocomposite has been developed. This nanocomposite was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform-infrared (FTIR) spectroscopy and contact angle measurements, which demonstrated that SDBS hemimicelles were attached on the surface of the 3D graphene foam. Electrochemical properties of the nanocomposite modified electrode were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. This electrochemical sensing interface exhibited excellent stripping performance for the analysis of Pb 2+ with the detection limit of 0.0145   nM, combining the advantageous of 3D graphene foam (well-defined macroporous structure, high electrical conductivity and specific area) together with the unique accumulating and depositing features of hemimicelle. The sensor was further applied to the determination of lead ion in real water samples with satisfactory results.