Porous Nickel Oxide Nanostructures Grown on Carbon Paper for Electrochemical Hydrogen Peroxide Detection in Green Tea

Abstract Hydrogen peroxide (H 2 O 2 ) shows an essential role in several biological processes and is frequently used as a preservative in food additive due to its inherent anti‐bacterial properties. In this report, an electrochemical H 2 O 2 sensor was made up of porous NiO nanostructures grown on carbon paper (CP) electrodes. The growth of porous NiO nanostructures was confirmed by scanning electron microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy studies. The sensor response was characterized by cyclic voltammetry and amperometric i – t study. The developed porous NiO‐deposited CP electrode demonstrated high sensitivity (∼40.35 mA mM −1 cm −2 ) in the linear detection range of 10 µM–1 mM. Such a paper‐based sensing electrode also exhibited an ultra‐low detection limit (∼3.87 nM), excellent stability, and selectivity. Real‐time H 2 O 2 detection in green tea samples was investigated using the developed sensor for practical application.