Tyrosine-assisted preparation of Ag/ZnO nanocomposites with enhanced photocatalytic performance and synergistic antibacterial activities

Abstract
In this paper, Ag/ZnO metal-semiconductor nanocomposites were prepared through a facile one-pot hydrothermal method with the assistance of tyrosine. The synthesized samples were structurally characterized by x-ray diffraction, scanning electron microscope, transmission electron microscope and x-ray photoelectron spectroscopy. It was shown that the added tyrosine served both as a shape conductor for the formation of ZnO faceted nanorods and as a reducing agent of Ag(+) ions. In the reaction process, the complexation of Ag(+) with NH(3) and OH(-) decreased the redox potential of Ag(+)/Ag, which prevented the formation of isolated Ag nanoparticles in solution. The prepared Ag/ZnO nanocomposites showed potential applications in photodegradation of organic dye pollutants and destruction of bacteria.