Microwave-assisted synthesis, photocatalysis and antibacterial activity of Ag nanoparticles supported on ZnO flowers

ZnO flowers with different Ag contents were successfully synthesized by a simple microwave method. Phase and morphologies of heterostructure Ag/ZnO composites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The results showed that heterostructure Ag/ZnO composites were composed of face centered cubic Ag supported on hexagonal ZnO flowers of hexagonal prism nanorods with 100 nm wide and about 2-3 mu m long, including the detection of Ag 3d(5/2) and Ag 3d(3/)(2) for metallic Ag of 10 wt% Ag/ZnO composites. The photocatalytic activity of heterostructure Ag/ZnO composites was evaluated through photodegradation of methylene blue under UV light. Escherichia coli DH5 alpha (gram-negative bacteria) and Stapphylococcus aureus ATCC 25923 (gram-positive bacteria) were used to test for antibacterial activity. The 10 wt% Ag/ZnO composites showed the best performance for photocatalysis and had the antibacterial activity.