The preparation of CuO nanoparticles using leaf extract of walnut and persimmon plants and investigation of their antibacterial properties

In this work, CuO nanoparticles were synthesized using leaf extract of walnut and persimmon plants as chelating and capping agents. The prepared CuO NPs were investigated by FT-IR, XRD, FESEM, EDS, TEM and TGA. Reaction of the phenolic compounds in the aqueous leaf extracts with CuCl2 solution form insoluble Cu2 nanocomplexes which then transform into CuO NPs by heat treatment at 300 °C. It will be expected, the metal ions are connected to constituents of extract from nearby carbonyl and hydroxyl groups on phenyl ring or alone OH groups. Decreasing of mass in thermal analysis of Cu2 nanocomplexes show that these materials are decomposed and transformed into CuO NPs. According to the TEM images, the mean particles size of spherical CuO NPs prepared from the leaf extract of walnut was in the range of 20 nm. The Cu2 nanocomplexes or CuO NPs exhibit antibacterial activity against some pathogenic bacterial strains such as Escherichia coli and Staphylococcus aureus.