Studies on Performances of Copper Oxide Nanoparticles from Catharanthus Roseus Leaf Extract

Copper Oxide Nanoparticles (NPs) have been successfully synthesized through the green synthesis route using Catharanthus roseus leaf extract that acted as an efficient stabilizer and capping agent of the NPs. The as-prepared CuO is then calcined at 400 °C, 500 °C, and 600 °C in order to gain better crystalline CuO NPs. The X-ray Diffraction (XRD) analysis of calcined samples showed that the particles were crystalline with hexagonal and monoclinic structure and the crystallite size was found to be about (30.77–13.25)nm for CuO. The surface morphology of the NPs was investigated by Scanning Electron Microscopy and Field Emission Scanning Electron Microscopy (FESEM) which showed that NPs were spherical in shape with uniform size distribution. Elemental analysis of the NPs was carried out with Energy Dispersive X-ray (EDX) Spectroscopy and it indicated the elemental signature of the presence of Copper, Oxygen, and Carbon in the CuO NPs. The Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that the capping agents of the NPs contained the functional groups alcohol, alkene, ketone, terpenoid, and organic acid. The thermal stability of CuO NPs was investigated using Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA). DSC showed one exothermic peak. The heat enthalpy of CuO NPs is 2326 j/g and 242.7 μVs/mg, respectively. The percentage of weight loss was about 13.33% for CuO as found from TGA. The CuO NPs were paramagnetic in nature with zero coercivity and zero remanence magnetization which was observed using a Vibrating Sample Magnetometer (VSM). The average crystallite size was determined by the Scherer formula which showed that the crystallite size of calcined CuO NPs decreases with an increase in calcination temperature. But the crystallite size increases with calcination temperature, which supported the results of XRD and VSM.