Strong efficiency improvement in dye-sensitized solar cells by novel multi-dimensional TiO2 photoelectrode

Highlights: • TSC was synthesized by hydrothermal approach for the first time. • TSC was composed of 0D nanoparticle, 1D nanobelt, 2D nanosheet and 3D hierachical micro-sphere. • TCS featured better dye-adsorption capacity, higher electronic-transport and stronger light scattering ability. • TCS-DSSC showed a strong efficiency enhancement by 58% compared with P25-DSSC (4.33%). Titanium dioxide (TiO₂) based dye-sensitized solar cells (DSSCs) often exhibit superior power conversion performance. Here we report a DSSC with novel hierarchical TiO₂ composite structure (TCS) composed of anatase TiO₂ micro-spheres and rutile TiO₂ nanobelt framework by hydrothermal approach for high-performance. As photoanode, the TCS based DSSC shows a strong efficiency enhancement by 58% compared with Degussa TiO₂ (P25)-DSSC (4.33%). The excellent performance is mainly attribute to its special multi-dimensional structures of TiO₂: much active sites of 0D nanoparticle with exposed excellent {001} facet, special electronic transmission channel of 1D nanobelt, good dye adsorption capacity of 2D nanosheet and high light scattering ability of 3D micro-spheres. The novel multi-dimensional TCS materials will open up a new avenue to the electronic devices fields.