Improved photocatalytic activity of self-assemble TiO2 nanobelts with Au nanoparticles

•The composition of Au nanoparticles promoted the transfer of charge carriers.•The band gap of s-TiO2 is enlarged because of quantum confinement effect.•The Au/s-TiO2 with large specific surface area exhibited enhanced photocatalytic activity. Self-assemble TiO2 nanobelts composited with Au nanoparticles were prepared by hydrothermal method and followed by the deposition of Au nanoparticle on the surface of spheres. It is found that the Au/s-TiO2 sample exhibits a much better photocatalytic activity under UV light irradiation, compared with s-TiO2 and TiO2 nanoparticles. The band gap is enlarged because of the quantum confinement effect, accompanying stronger redox ability; the specific surface area is also increased due to unique self-assemble one-dimensional nanobelts; the composition of Au nanoparticles would promote the separation of charge carriers. All these factors contribute to the enhanced photocatalytic activity of Au/s-TiO2, indicating the potential application of the self-assemble low-dimensional nanostructure as new improved functional nano-materials.