Facile green synthesis of MoO2/BiOCl nanocomposite using Hibiscus rosa-sinensis leaf extract and its application in visible-light-driven oxidative transformations

Abstract

This article describes a green approach for synthesizing MoO₂/BiOCl nanocomposite using a combustion procedure with Hibiscus rosa-sinensis leaf extract as a renewable fuel source, which also acts as a reducing and stabilizing agent. The synthesized material is characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR), confirming the successful formation of the nanocomposite. The photocatalytic performance of MoO₂/BiOCl nanocomposite was evaluated for visible-light-driven oxidative transformations of different aromatic amines to nitroarenes. The unique structure of MoO₂/BiOCl provides better accessibility to the reactant molecules, facilitating faster and more efficient oxidation. The advantages of this oxidative process are high catalytic efficiency, mild reaction conditions, recyclability, environmental sustainability, and producing nitroarenes in good to exceptional yields (67–95 %). The conversion of the compounds was validated using gas chromatography-mass spectrometry (GC–MS), ¹H NMR, and ¹³C NMR. The results demonstrated that the MoO₂/BiOCl nanocomposite exhibited enhanced photocatalytic activity compared to its components, attributed to the synergistic effects between MoO₂ and BiOCl. The use of Hibiscus rosa-sinensis leaf extract in the synthesis is not only environmentally friendly and cost-effective but also contributes to the stability and efficiency of the nanocomposite.