Vinoth Kumar Ponnusamy
Kaohsiung Medical University, Taiwan
Title: Facile one-step synthesis of porous graphitic carbon nitride nanosheets/oxidized multi-wall carbon nanotubes composite for simultaneous anodic stripping voltammetric detection of heavy metals in food samples
Biography
Biography: Vinoth Kumar Ponnusamy
Abstract
We demonstrate a facile one-step synthesis of three-dimensional (3D) porous graphitic carbon nitride nanosheets (P-g-C3N4-NSs)/oxidized multi-wall carbon nanotubes (O-MWCNTs) composite by simultaneous chemical oxidation of bulk g-C3N4-NSs and bulk MWCNTs. This one-step chemical oxidation method results in the simultaneous formation of acid functional groups on the basal surfaces of both g-C3N4 and MWCNTs, and also the formation of the porous structure of P-g-C3N4/oxidized MWCNTs composite at the same time. The acid functionalization and surface morphology of the prepared P-g-C3N4-NSs/O-MWCNTs composite were examined using attenuated total reflectance infrared spectroscopy (ATR-IR), X-ray diffraction methods (XRD), and high-resolution transmittance electron microscopy (HR-TEM). The electrochemical properties of the P-g-C3N4/O-MWCNTs composite modified screen-printed electrode (SPE) was studied using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry techniques (DPV). P-g-C3N4/O-MWCNTs/SPE exhibits excellent sensitivity and selectivity towards the simultaneous detection of heavy metals (Cd, Hg, Pb & Zn) in food samples with the detection limits (S/N=3) ranging between 8 to 60ngL-1 under stripping analysis. The practical feasibility of the developed sensor was examined for simultaneous detection of heavy metals in various food samples, and the obtained results exhibit good accuracy and good reproducibility. These results imply that the developed composite might be an alternative sensor material for practical applications in electrochemical detection of heavy metals in foods.