A novel 3D structure composed of strings of hierarchical TiO2 spheres formed on TiO2 nanobelts with high photocatalytic properties

•The novel TiO2 nanostructure (HSN) is fabricated for the first time.•HSN is composed of strings of anatase hierarchical spheres and rutile nanobelt.•HSN presents a larger SBET of 191 m2/g, 3 times larger than the Degussa P25 (59 m2/g).•HSN owns three kinds of dimensional TiO2 (1D, 2D and 3D) simultaneously.•HSN exhibits better photocatalytic performance compared with Degussa P25.

A novel hierarchical titanium dioxide (TiO2) composite nanostructure with strings of anatase TiO2 hierarchical micro-spheres and rutile nanobelts framework (TiO2 HSN) is successfully synthesized via a one-step hydrothermal method. Particularly, the strings of hierarchical spheres are assembled by very thin TiO2 nanosheets, which are composed of highly crystallized anatase nanocrystals. Meanwhile, the HSN has a large surface area of 191 m2/g, which is about 3 times larger than Degussa P25. More importantly, the photocatalytic activity of HSN and P25 were evaluated by the photocatalytic oxidation decomposition of methyl orange (MO) under UV light illumination, and the TiO2 HSN shows enhanced photocatalytic activity compared with Degussa P25, as result of its continuous hierarchical structures, special conductive channel and large specific surface area. With these features, the hierarchical TiO2 may have more potential applications in the fields of dye-sensitized solar cells and lithium ion batteries.

Graphical abstractNovel TiO2 with anatase micro-spheres and rutile nanobelts is synthesized. Enhanced photocatalysis is attributed to hierarchical structures (3D spheres), conductive channel (1D nanobelts) and large specific surface area (2D nanosheet).Figure optionsDownload full-size imageDownload as PowerPoint slide