Biological synthesis of nanomaterials using plant leaf extracts

Several plant leaf extracts (Pine, Persimmon, Ginkgo, Magnolia, Platanus, Cherry, etc.) were used and compared for their extracellular synthesis of nanomaterials. Stable gold, silver, copper, and platinum nanoparticles were formed by treating aqueous solution of HAuCl₄, AgNO₃, CuSO₄·5H₂O, and H₂PtCl₆·6H₂O, respectively, with the plant leaf extracts as reducing agent. The biologically synthesized silver and copper nanoparticles showed antibacterial activities when they were coated on the surface of latex foam products. Graphene oxide, which was prepared by oxidation of natural graphite powders, was also reduced using plant leaf extracts. The reduced materials were characterized by elemental analysis, UV-vis spectroscopy, FT-IR, Raman spectroscopy, X-ray diffraction, transmission electron microscopy, thermo-gravimetric analysis, etc.