Design, synthesis of uniform Au nanoparticles modified Fe2O3–TiO2 coaxial nanotubes and their enhanced thermal stability and photocatalytic activity

Abstract

Iron-coated TiO₂ coaxial nanotubes (Fe₂O₃/TiO₂ nanotubes) synthesized by treating TiO₂ nanotubes with Fe(OH)₃ sol are used as a support, and gold nanoparticles are loaded on the support by a simple one-pot strategy using lysine as both the linker and the capping agent. The obtained Au/Fe₂O₃/TiO₂ hybrid nanotube materials are characterized by TEM, XRD, XPS, UV-vis, AAS and nitrogen adsorption. The photocatalytic performance is evaluated by the photocatalytic degradation rates of methyl orange under UV light irradiation. The effects of Au content, the absence/presence of lysine and Fe₂O₃, the pH value of solution and the addition amount of H₂O₂ to solution on the photocatalytic performance of Au/Fe₂O₃/TiO₂ nanotubes are investigated. The results reveal that gold nanoparticles capped by lysine can be highly dispersed on the supports against aggregation, and the products exhibit higher thermal stability and photocatalytic activity in comparison to pristine TiO₂ nanotubes.