Journal of Applied Electrochemistry, Vol.45, No.4, 365-373, 2015
Electrochemical analysis of parathion-ethyl using zirconium oxide-laponite nanocomposites-modified glassy carbon electrode
A simple, cost-effective electrode surface modified with a mixture of laponite clay and zirconium oxide (laponite-ZrO2) gel nanocomposites has been developed for the detection of parathion-ethyl pesticide. Different composition ratios of laponite-ZrO2 gel were used to modify the surface of glassy carbon (GC) electrode. The fabricated electrode was characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, and attenuated total internal reflectance infrared spectroscopy. Cyclic voltammetry and differential pulse voltammetry were employed to investigate the modified laponite-ZrO2 electrode toward the electrochemical oxidation of several organophosphate compounds. The obtained results showed that the laponite-ZrO2 nanocomposites-modified GC electrodes have improved the sensitivity and selectivity of parathion-ethyl detection with a limit of detection as low as 1.6 ng mL(-1) in the linear range of 0-58.3 ng mL(-1) (R (2) = 0.994). Furthermore, the modified electrodes showed good stability at 71.6 +/- A 3.2 % after 14 days with the relative standard deviation of 4.36 % (n = 20).
Keywords:Laponite clay;Zirconium oxide;Sol-gel;Organophosphate compounds;Differential pulse voltammetry