Construction of Au@TiO_2/graphene nanocomposites with plasmonic effect and super adsorption ability for enhanced visible-light-driven photocatalytic organic pollutant degradation

摘要

Au@TiO_2/graphene (Gr) composite with visible-light response was fabricated. The prepared samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscope, and diffuse reflection spectroscopy, respectively. The results indicated that metallic Au nanoparticles with round shape and about 10 nm in size were loaded on TiO_2 particles uniformly, and Au@TiO_2 was grafted on Gr shaped in thin and big sheets. Photocatalytic degradation of 2,4-dichlorophenol (2,4-DCP) was conducted under the visible-light irradiation (420 nm) in order to evaluate the activity of photocatalysts. The light absorption spectrum of TiO_2 was extended to visible-light region by loading Au nanoparticles with plasmonic effect and 2,4-DCP could be degraded with Au@TiO_2 and Au@TiO_2/Gr by photocatalysis under visible light. Compared to that with Au@TiO_2, the elimination rate of 2,4-DCP was increased with Au@TiO_2/Gr. This enhanced photocatalytic performance was attributed to the concentration effect due to the improved adsorption performance introduced by Gr.