INVESTIGATION OF THE EFFECT OF PH VALUES ON THE PHYSICAL CHARACTERISTICS OF COPPER OXIDE NANOSTRUCTURES BY GREEN ASSISTED METHOD USING Origanum vulgar PLANT EXTRACTS

Copper oxide (CuO) nanoparticles were synthesized using the green method. The extract of the Origanum vulgare (O. vulgare) leaves has been used as a capping and reducing agent of CuO nanoparticles. The influence of pH values in the green growth solution (7.5–10.5) on nanoparticle properties was investigated using various characterization techniques. The obtained results from both optical properties and FTIR analysis confirmed that the O. vulgare plant extract is a highly efficient reducing and stabilizing agent. The UV-Visible spectrum of the O. Vulgare plant extract shows two distinct absorption peaks at 287.439 nm and 324.15 nm at ambient temperature. The FESEM results revealed that the pH of the growth solution significantly affects the morphology, shape, dimensions, and orientation of CuO nanoparticles. The sphere and rod-like nanoparticles were produced as the pH value changed from 7.5 to 10.5, with an average diameter in the range of (16.89-28.50) nm. The obtained results of XRD analysis confirmed that the fabricated CuO nanoparticles have a monoclinic crystal structure with crystalline size in the range of (10.7-17.81) nm. UV–Visible spectra of CuO nanoparticles at different pH values show strong UV absorbance < 300 nm and have band-gap energies in the range of (1.82-1.98) eV. The FTIR analysis of nanoparticles confirmed their purity and suggested that nanoparticles synthesized at pH 10 had improved quality and properties.