NiO–Co ₃ O ₄ –rGO as a Multicomponent Transition Metal Oxide Nanocatalyst for Ultra‐level Detection of Nitrite in Beef and Tap Water Samples

Abstract The detection of nitrite as a challenging compound in food industries has always been necessity. To this purpose, herein, two transition metal oxide‐based nanocatalysts, NiO–Co 3 O 4 (NC) and its reduced graphene hybridized form, –rGO (NCR), are synthesized by hydrothermal method characterized X‐ray diffraction, Raman spectroscopy, scanning electron microscope (SEM) images, energy dispersive analysis (EDAX) mapping. materials exploited to modify glassy carbon electrode fabricate an effective sensor for real samples through differential pulse voltammetry (DPV). NCR shows excellent sensitivity (40.44 µA per dec), very low limit (20 × 10 ‐9 m ), significant accuracy, good stability at the wide range ions (100–500 ) samples.