Received: 13 September 2019 Accepted: 8 January 2020
The green method for preparing metal and metal oxide nanoparticles is increasingly becoming popular as a result of its eco-friendliness compared with physical and chemical methods. The biomolecules inherent in plant extracts are known to serve as reductants and capping agents to form metal/metal oxide nanoparticles. This study, therefore, aimed to synthesize magnesium oxide nanoparticles (MgONPs) using the aqueous extract of Chromolaena odorata leaf. The type of phytochemicals present in the leaf extract was initially examined in a gas chromatograph–mass spectrometer (GC–MS). UV–visible (UV–Vis) spectrophotometric assessment indicated the formation of MgONPs by developing a peak at 270 nm, scanning electron microscopy (SEM) showed good surface properties, energy-dispersive X-ray analysis (EDX) confirmed the presence of MgO in the sample, transmission electron microscopy (TEM) revealed cubic-shaped MgONPs with average size 12.3 nm, X-ray diffractometry (XRD) confirmed the formation of MgO phase and Fourier transform infrared (FTIR) spectroscopy supported the capping role of the phytochemicals identified by GC–MS. Thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA) was further employed to study weight differentials during treatment and to corroborate the results of the GCMS and FTIR. The obtained MgONPs showed potential for application in catalysis and as antimicrobial agent. Since the plant used is a weed and is ubiquitous, the reported synthesis process could be upscaled for commercial production of MgONPS.