Ultrasound-assisted green biosynthesis of ZnO nanoparticles and their photocatalytic application

Abstract

Abstract Employing plant extracts to obtain nanomaterials is an ecofriendly and highly appreciated synthetic approach. In this work a simple, green chemistry method, based on sol–gel, was used for ZnO nanoparticles synthesis by using two Sudanese medicinal plant extracts: Adanosia digitata (ZnO-A) and Balanites aegyptiaca (ZnO-B) under ultrasonic energy. The X-ray diffraction (XRD) revealed the formation of wurtzite hexagonal ZnO nanostructures, while the scanning electron microscopy (SEM) analysis displayed their diverse morphologies. The X-ray photoelectron spectroscopy (XPS) data showed the impact of extract via the variation in of the O1s and Zn2p3/2 and Zn2p1/2 orbitals binding energy of Zn–O. The UV-visible investigation indicated a variation of bandgap energy (Eg), where the ZnO nanoparticles displayed the lowest Eg. The synthesized nanomaterials have exhibited high photocatalytic efficiency towards the methylene blue (MB) dye. The findings revealed the possibility of obtaining nanoparticles with tailored properties by using plants extracts.