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

Abstract

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.