A composite photoanode based on P25/TiO2 nanotube arrays/flower-like TiO2 for high-efficiency dye-sensitized solar cells

Abstract

In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 (Flo-TiO2) as overlayer, TiO2 nanotube arrays as interlayer and TiO2 nanoparticle (P25) as underlayer was fabricated as the photoelectrode of dyesensitized solar cells (DSSCs). Due to the introduction of Flo-TiO2, the three-layer composite film has strong light-scattering ability. Then, we have investigated and compared the photoelectric conversion properties of DSSCs based on three-layer structure (P25/TNT arrays/Flo-TiO2) photoelectrode and double-layer film (P25/TNT arrays) photoelectrode. It is found that DSSCs based on three-layer structure exhibit a high power conversion efficiency of 6.48% compared with the DSSCs composed of double-layer film (5.11%).