Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 20 3 2024 09 01 Efficient Single-Step Biosynthesis of Copper Nanoparticles using Essential Oil Extracted from Curry Leaves (Murraya koenigii) for Supercapacitor Electrodes in Energy Storage Applications 197 207 721800 10.22034/ijnn.2025.2025479.2499 EN Byrapogu Purna Chandra Rao Department of Chemistry, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Guntur - 522302, A.P., India 0009-0004-4603-4983 Uppu Naga Babu Department of Engineering Chemistry, S.R.K.R. Engineering College, Chinna Amiram, Bhimavaram - 534204, A.P., India 0000-0002-3328-9280 Bhagya Kumar Tatavarti Department of Chemistry, K.B.N. College (Autonomous), Kothapeta, Vijayawada - 520001, A.P., India 0000-0003-1589-2497 Kandula Rekha Department of Biotechnology, Dr.V.S Krishna Govt. Degree College, Visakhapatnam - 530022, A.P., India 0009-0008-3233-3578 Venkateswara Rao Anna Department of Chemistry, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Guntur - 522302, A.P., India 0000-0002-1705-2822 Journal Article 2024 03 26 <em>    Nanobiotechnology is an innovative branch of modern science that has brought significantly changed in material research. The present highlights the use of essential oil collected from curry leaves (Murraya koenigii) as a simple, affordable, and efficient reducing agent for the fabrication of copper oxide (CuO) nanoparticles (NPs). These NPs were evaluated for their potential as electrodes in supercapacitors. During the synthesis, the solution changed from pale blue to green and finally to reddish-brown. This indicates the reduction of Cu²⁺ ions in copper sulfate to CuO NPs, which showed a characteristic UV-visible absorption peak at 292 nm. GCMS analysis reveals that compounds such as α-Terpinene, Linalool, Myrcene, Geranyl acetate, Elemol, and Allo-Ocimene in the essential oil played a role in NPs formation. The NPs were primarily spherical in shape with 24 nm average particle size. These particles exhibit a monoclinic crystal structure with 81.26% of elemental copper. Cyclic voltammetry results showed specific capacitances of 369, 324, 305, 265, and 210 F/g respectively at scan rates of 10, 20, 40, 60, and 100 mV/s. The maximum specific capacitance was noticed to be 369 F/g, with a retention capacity of 97.6% even after 6000 charge-discharge cycles demonstrating that these NPs have suitability for supercapacitor applications. These results suggest that biologically synthesized CuO NPs have great potential for utilization as energy storage devices, particularly as supercapacitor electrodes.</em> https://www.ijnnonline.net/article_721800_0c78ce26c6525c898690ddea4e9835bf.pdf