A novel enzyme-less amperometric sensor for hydrogen peroxide based on nickel molybdate nanoparticles

Abstract In the present study, nickel molybdate (NiMoO4) nanoparticles were prepared via a facile citrate sol-gel method. The characterization of NiMoO4 was thoroughly researched by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). Because of the outstanding electron-transfer ability of monoclinic NiMoO4 and the large surface area of nanoparticles, the prepared NiMoO4 was utilized as electrocatalyst for the oxidation of hydrogen peroxide (H2O2). A glassy carbon electrode (GCE) coated with NiMoO4 was employed for the electrochemical detection of H2O2. Under optimum conditions, the amperometric sensor showed remarkable sensing ability toward H2O2 oxidation, offering wide linearity in the concentration range of 0.1–1550 μM with an excellent coefficient of determination (>0.999). A low detection limit (based S/N = 3) of 0.01 μM was also achieved. The proposed assay depicted high sensitivity, good reproducibility and anti-interference performance in the determination of H2O2 concentrations. The applicability of the sensor was examined with analysis of H2O2 in real water samples.