An Electrochemical Sensor Based on an Ionic Liquid Covalently Functionalized Graphene Oxide for Simultaneous Determination of Copper (II) and Antimony (III).

Abstract: Graphene oxide (GO) was chemically grafted by ionic liquid (IL) containing amino groups for preparation of IL covalently functionalized GO (IL–CFGO). SEM, FTIR and XRD results confirmed that IL had been successfully anchored on GO surface, resulting in more active sites and higher conductivity. The IL–CFGO composite was coated on the surface of carbon IL electrode (CILE) to construct electrochemical sensor for simultaneous detection of Cu(II) and Sb(III). The experimental factors including pH, deposition time and potential were optimized. Differential pulse voltammetry was employed for the simultaneous determination of Cu(II) and Sb(III) under the optimal conditions. The IL–CFGO/CILE exhibited the wide linear ranges of 0.1∼28 μM for Cu(II) and 0.1∼20 μM for Sb(III) with detection limits of 0.04 and 0.06 μM, respectively. The proposed sensor displayed good reproducibility, selectivity and acceptable stability owing to the contributions of the more active sites and the enhanced conductivity. [ABSTRACT FROM AUTHOR]