An emergent electrochemical sensor based on spinel zinc manganese oxide decorated on amine-functionalized boron nitride for enhanced electrochemical determination of herbicide mesotrione

Abstract

Mesotrione (MTO) is a herbicide that is commonly used in agriculture; unfortunately, this chemical often makes its way into aqueous environments. In this study, an MTO sensor was fabricated based on spinel zinc manganese oxide (ZnMn2O4, ZMO) nanoparticles (NPs) and an amine-functionalized boron nitride (NH2-BN) composite. ZMO was synthesized using a coprecipitation technique, and NH2-BN was prepared by a urea-assisted ultrasonication/stirring method. The nanocomposite of ZMO NPs/NH2-BN was prepared using the sonication method. The crystallinity, oxidation states, and functionality of the catalysts were investigated using physiochemical characterization techniques: powder X-ray diffraction analysis, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. In addition, the surface morphology and topology of the ZMO NPs/NH2-BN composite were analyzed by field-emission scanning electron microscopy and high-resolution transmission electron microscopy. The ZMO NPs/NH2-BN/glassy carbon electrode (GCE) exhibited a well-resolved MTO reduction peak in cyclic voltammetry experiments due to the synergetic effect between the aggregated ZMO NPs and NH2-BN. In addition, ZMO NPs/NH2-BN/GCE exhibited a low limit of detection of 1.5 nM, high sensitivity (1.791 µA µM−1 cm−2), and broad linear ranges (0.01–12.51 µM and 18.51–1777.51 µM). A ZMO NPs/NH2-BN/GCE sensor prototype was used to effectively detect MTO in environmental water samples with good recovery.