Optimization and Application of TiO2 Hollow Microsphere Modified Scattering Layer for the Photovoltaic Conversion Efficiency of Dye-Sensitized Solar Cell

In our study, the dye-sensitized solar cells (DSSCs) with double-layer thin films were fabricated. The active bottom layer of the structure was mainly made of the commercially available titanium dioxide (TiO
₂
) nanoparticles. TiO
₂
hollow microspheres (THS) were doped into the TiO
₂
composite material and used as the scattering top layer. The THS prepared by the one-pot hydrothermal method was composed of irregularly arranged nanoparticles. Meanwhile, we also characterized the synthesized hollow TiO
₂
microspheres by both the scanning electron microscope (FE-SEM) and the X-ray diffractometer (XRD). Besides, we produced DSSCs with different weight percentages (0.5wt%, 1wt%, and 2wt%) of THS photoanodes. The DSSCs based on pure TiO
₂
showed the short-circuit current (J
_SC
) of 8.33 mA/cm
²
and the photovoltaic conversion efficiency (PCE) of 3.75%. The DSSCs manufactured using 1wt%-THS photoanode had J
_SC
of 12.02 mA/cm
²
and a PCE of 5.01%. When compared with the J
_SC
and PCE based on pure TiO
₂
DSSCs, a significant improvement in the structure was observed.