Synthesis and improved dye-sensitized solar cells performance of TiO₂ nanowires/nanospheres composites

TiO₂ nanowires/nanospheres (TiO₂ NWs/NSs) composites photoanode films were successfully synthesized via a direct two-step method, which involves preparation of TiO₂ nanospheres and adding of TiO₂ nanowires, and the dye-sensitized solar cells with improved performance were successfully assembled. The as-prepared samples were carefully characterized by X-ray diffraction, field-emission scanning electron microscopy, UV–visible spectrophotometer, respectively. We investigated the effect of different TiO₂ NWs additions on morphology, adsorption properties of dye and photoelectric conversion properties of DSSC. The experimental results indicate that the composites structural photoanode film with suitable loading amount of TiO₂ NWs present a uniform morphology. As a result, owing to its better absorption properties of N719 dye molecules and superior conductivity of photogenerated electrons, the sample with TiO₂ NWs content of 10 % shows the highest photocurrent, and it exhibits an enhanced conversion efficiency of 6.37 % since it has the appropriate amount of TiO₂ NWs, much higher than that of pure TiO₂ NSs.