Green Synthesis of Copper Oxide Nanoparticles Using Rauvolfia serpentina Root Extract and its Characterization

The development of sustainable and environmentally benign methods for nanoparticle synthesis is of growing importance in nanotechnology. In this study, copper oxide (CuO) nanoparticles were synthesized using Rauvolfia serpentina root extract, a dark brown coloured solution acts as a natural reducing and stabilizing agent. The color change of the reaction mixture (dark brown to dark maroon red) and the biosynthesized plant extract show a characteristic absorption peak at 334 nm in UV?Vis spectroscopy, confirming nanoparticle formation. The sharp peaks in the FTIR analysis at 1083 cm?? and 1045 cm?? indicated the involvement of phytochemicals such as phenolics, alkaloids, and flavonoids in the reduction and capping processes. X-ray diffraction (XRD) analysis revealed that the nanoparticles exhibited a monoclinic CuO crystal structure (JCPDS 48-1548) with crystallite sizes in the 20?30 nm range, as estimated by the Scherrer equation. Scanning electron microscopy (SEM) revealed predominantly spherical nanoparticles with average particle sizes ranging from 40 to 80 nm, consistent with XRD findings. These findings highlight the potential applications of biogenic CuO nanoparticles in catalysis, antimicrobial activity, sensors, environmental remediation, and energy storage, while aligning with the principles of green chemistry.