Voltammetric and amperometric determination of iodate using a modified glassy carbon electrode based on PW12/MOF/P@ERGO nanohybrid

A nanocomposite of tungstophosphoric acid (PW12), metal-organic framework (MOF), and graphene oxide (GO) (PW12/MOF/GO) was electrodeposited at -1.5 V by amperometry technique from a suspension of PW12/MOF/ GO nanocomposite in 0.01 M H3PO4. The synthesized PW12/MOF/GO was characterized by Fourier-transform infrared spectroscopy, X-ray powder diffraction, Transmission electron microscopy, inductively coupled plasma-optical emission spectrometry, and Brunauer-Emmett-Teller analytical techniques. The morphology of PW12/MOF/P@ERGO/GCE was evaluated by FE-SEM images and energy dispersive spectroscopy. The modified GCE was an electrochemical sensitive surface for IO3- sensing. The PW12/MOF/P@ERGO/GCE had a higher reductive current in the electro-reduction of IO3- than bare GCE. The proposed sensor by amperometric experiments displayed a linear range of 10-2000 & mu;M with a limit of detection (LOD) of 3.86 & mu;\M, a sensitivity of 20.0 & mu;A mM-1, and excellent selectivity for IO3- detection in the presence of other potential interfering species. Moreover, the modified GCE was successfully applied for IO3- detection in mineral water and commercial table salt.