Improvement of the performance of purple carrot sensitized solar cells by acidic treatment of FTO glass substrate and TiO₂ film

In this paper, dye sensitized solar cells were prepared using titanium dioxide (TiO₂) and natural dye extracted from purple carrot. The performance of dye sensitized solar cells was significantly improved through the pre- and post-treatments of the fluorinated tin oxide (FTO) glass substrate and the TiO₂ film using hydrochloric (HCl), phosphoric (H₃PO₄), and nitric (HNO₃) acids. The results showed that the pre-treatment of the FTO with H₃PO₄ and the post-treatment of TiO₂ with HNO₃ resulted in improved efficiencies of 130% and 250%, respectively.