Standardization of photoelectrode area of dye-sensitized solar cells

This study is aimed to provide new insights on the scalability of dye-sensitized solar cells (DSCs). The DSCs of electrode area up to similar to 2 cm(2) were fabricated using commercially available P25 TiO2 particles, N3 dye, and iodide/triiodide electrolyte. The photovoltaic conversion efficiency follows a biexponential decay, the main contributor to which is the short circuit current density (J(SC)). Interesting features were observed in the electrochemical impedance spectra and charge transport parameters in the devices as the photoelectrode areas were increased. Results show that electrons from an area above a threshold are not collected due to varied choice of diffusion pathways. Furthermore, this study identifies that the area of the photoelectrode for reporting the efficiency needs to be fixed at similar to 0.5 cm(2) for 25 nm TiO2 particles because below this value it strongly varies. On the other hand, the study provides opportunities to build high efficiency dye-sensitized solar cells using the current choice of materials.