Tuning the dye aerosol impaction and TiO2 nanoparticle stacking structures for High-Efficiency Dye-Sensitized solar cells

Abstract

The rapid manufacturing of high-efficiency dye-sensitized solar cells (DSSCs) is limited by the slow dye adsorption on TiO2 nanoparticles (NPs)-accumulated photoelectrode using conventional dip-coating process. Therefore, we aim to accelerate the adsorption of dyes that are attached on TiO2 NPs by employing an aerosol impactor. Herein the aerosolized dyes are designed to get deposited rapidly on the TiO2 NPs-accumulated photoelectrode. In addition, to effectively trap the irradiated sunlight in DSSCs, we assemble the photoelectrodes incorporated with bilayered TiO2 thin films comprising small TiO2 NPs-based underlayer and large TiO2 NPs-based overlayer as dye-supporting and light-scattering mediums, respectively. Furthermore, the effects of dye aerosol impaction and TiO2 stacking structures on the efficiency of DSSCs are examined. The power conversion efficiency (PCE) of DSSCs comprising a N719 dye-supporting layer treated with dip-coating process was determined as ∼ 5.67%; however, when the bilayered TiO2 thin films with an optimized thickness ratio of light-scattering overlayer and dye-supporting underlayer were coated with N719 dyes using dye aerosol impactor, the resulting PCE increased to ∼ 7.46%. This suggests that the photovoltaic characteristics of DSSCs can be enhanced considerably using the effective TiO2 NP stacking structures coated with rapid, uniform, and strong aerosol dye adsorption throughout the TiO2-based photoelectrodes.