Preparation of mixed-valent manganese-vanadium oxide and Au nanoparticle modified graphene oxide nanosheets electrodes for the simultaneous determination of hydrazine and nitrite

Abstract

• Mixed valent metal–metal oxides were performed by SEM-EDX, XPS, CV, EIS techniques. • Simultaneous and individual determination of hydrazine and nitrite. • LOD for LSV 3.0 and 10.0 µM for hydrazine and nitrite, respectively. • AuNP/MnOx-VOx/ERGO was tested in river water and food samples. In this study, for the first time in the literature, simultaneous and individual determination of hydrazine and nitrite have performed by combining the triple electrocatalytic properties of electrochemically reduced graphene oxide (ERGO), multivalent metal oxide (MnOx-VOx) films and gold nanoparticles (AuNPs). Characterization studies of AuNP/MnOx-VOx/ERGO electrode were performed using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) methods. The determinations of hydrazine and nitrite in pH 8 BR buffer solution were studied using linear sweep voltammetry (LSV) and amperometry methods. The limit of detection (LOD) for simultaneous detection was 3.0 and 10.0 µM for hydrazine and nitrite, respectively, and the LOD for amperometric detection was 0.1 and 0.33 µM, respectively. AuNP/MnOx-VOx/ERGO electrode was tested for the determination of hydrazine and nitrite in river water and food samples, and this electrode provides a recovery of 91.0% to 113.0%. Also, the electrode has practical preparation, good repeatability, selectivity, accuracy.