P1.7 Elaboration of reduced graphene oxide electrodes functionalized with RGO-iron oxide composite for nitrite detection in water

Abstract

In this paper, we propose a novel nitrite sensor based on reduced graphene oxide electrodes elaborated by light scribing. .First, graphene oxide was deposited on flexible substrate, which was previously plasma treated and wetted by a Poly(diallyldimethylammonium chloride) polymer solution.Then, in order to tune and enhance the sensitivity, the working electrode has been modified by layer-by-layer deposition of iron oxide-reduced graphene oxide nanocomposite (ION-rGO).The working electrode has been characterized at different levels of modification by scanning electron microscopy (SEM) and dispersive X-ray spectroscopy (EDX) showing a successful deposition and functionalization.Furthermore, electrochemical characterizations have been carried out by impedance spectroscopy and cyclic voltammetry (CV) and quantitative measurements for nitrite detection by differential pulse voltammetry (DPV).The experimental results demonstrate a good electrochemical response for nitrite with a sensitivity of 0.314 µA/mM.Several successive scans by CV at 50 mV/s in 1 mM nitrite solution show that the electrode remains stable and the sensitivity slightly reduces due to surface contaminations.The proposed fabrication procedure has a significantly better performance in comparison with some reported state-of-the art electrodes [12].