Au nanoparticles decorated reduced graphene oxide/layered double hydroxide modified glassy carbon as a sensitive sensor for electrocatalytic determination of phenazopyridine

Abstract

Abstract A novel and sensitive phenazopyridine sensor has been fabricated by electrodepositing of Au nanoparticles on layered double hydroxide/reduced graphene oxide modified glassy carbon. Study of layer formation on the electrode surface was followed by electrochemical impedance spectroscopy and cyclic voltammetry using redox couples Fe(CN)63−/4− species. The nanocomposite was characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared and energy dispersive X-ray spectroscopy. The fabricated sensor exhibits excellent electrochemical catalytic activities toward the oxidation of phenazopyridine due to the synergistic effects between layered double hydroxide, reduced graphene oxide and Au nanoparticles. The oxidation peak current was proportional to the concentration of phenazopyridine from 0.08 to 405.0 μmol L−1 with a detection limit of 0.009 μmol L−1 at signal to noise ratio of 3. The capability of the proposed sensor for determination of phenazopyridine was examined by the standard addition method in real samples.