Synthesis and characterization of copper oxide nanoparticles by Aloe Barbadensis leaves via green method

Introduction: Green approach becomes the most pronounced and effective method for synthesizing nanoparticles due to its non-toxic features, environment friendly behavior, recyclability and cost-effective methods as compared to other physical and chemical methods (1). The Green route involves different biological agents like bacteria, fungi, algae but plant extract method proved himself more effective than other biological agent by various studies. In green approach plant extract serves as reducing and capping agent for synthesization of nanoparticles of desired shape and morphology (2). The concentration of phytochemicals present in the plant extract, pH of solution, reaction temperature are the different parameters which affect the synthesis process of metal or metal oxide nanoparticles. The phytochemicals works as reducing and stabilizing agent. In this paper plant extract mediated synthesized CuO nanoparticles were reported and characterized by different techniques. Methods: For synthesis of CuO nanoparticles Cu(So4)2.5H2O (2.5 gm) mixed in 100 ml D.I. (Solution A).and 4 gm NaOH Pallets dissolved in 50 ml DI (Solution B) then mixed solution A and Solution B with 20 ml aloevera leaf extract. .The whole mixture was stirred at 50 oC for 3 hours in Glove box to avoid the environment contamination. The solution becomes blackish in Colour after 3 Hours which shows the formation of nanoparticles .leave it for 10 days. After thoroughly washing with DI water, Filtering and drying in oven overnight we found CuO nanoparticles in powder form. The CuO nanoparticles thereby obtained were characterized by different analytical techniques. XRD revealed the average crystalline size, FESEM revealed the morphology of nanoparticles, detection of elemental composition by EDS, Optical properties by UV-Visible spectroscopy , and the presence of different functional groups revealed by FTIR. Results & Discussions: The XRD pattern shows the different intense peaks in good agreement with data files. The crystalline size determined with respect to two intense peaks found between 300 to 400 which provides the crystalline size 5-6 nm. The SEM images revealed that the synthesized nanoparticles are of spherical shape with aggregation due to large surface area and high surface energy. The EDS pattern revealed the existence of Cu and O in our sample with atomic weight percent of 75.73 % and 24.27% respectively. UV-Visible spectra revealed the absorbance peaks in absorbance spectra at 220 nm and 388 nm which explains the newly formed nanoparticles of different size and shape. FTIR spectra revealed the functional groups which are attached with the surface of nanoparticles. The peaks found at 701.48 cm-1,594.92 cm-1,515.12 cm-1,483 cm-1 found in FTIR spectra shows the presence of Cu-O vibrations and also verifies the purity of CuO nanoparticles. Conclusions: In this paper, CuO nanoparticles were successfully synthesized by an ecofriendly and cost effective approach (Green synthesis) by using Copper sulphate penta hydrate (Cu(So4)2.5H2O) as precursor salt and aloevera leaf extract as reducing and capping agent. Therefore, the Green route for synthesization has a remarkable potential in the field of nanotechnology. Keywords: Copper Oxide, Nanoparticles, Green synthesis, Plant extract. Acknowledgment: The authors are thankful to Department of Physics and Centre of Nonconventional energy Resources, University of Rajasthan, Jaipur, India for providing research facilities. References: 1. Gour A, Jain N K et al. Advances in Green synthesis of nanoparticles, Nanomedicine and Biotechnology, 2019; 47(1): 844–851. 2. Augustine R, Hasan A. Emerging applications of biocompatible phytosynthesized metal/metal oxide nanoparticles in healthcare, Journal of Drug Delivery Science and Technology, 2020; 56(Part A), 101516