Proceedings of 6th International Conference on Hybrid and Organic Photovoltaics (HOPV14)
Publication date: 1st March 2014
Highly conductive poly (bis-EDOT) was mostly used for polymer based HTMs since bis-EDOT has a much lower oxidation potential than EDOT. However, bis-EDOT, as dimer, is difficult to synthesize so that its cost is high for widespread application. Thus, finding alternative monomers is an important issue for the commercial application of sDSCs.
Poly (3, 4-ethylenedioxypyrrole), PEDOP as hole transporting material combined with metal free organic sensitizers were for the first time efficiently used to obtain all solid state dye solar cells. The devices combining PEDOP and sensitizer D35 showed a 10 times higher efficiency of 4.53%, at 46 mWcm-2 irradiance, than the Ru-Z907-based device, due to the effective suppression of electron recombination.
This fact indicates that the PEDOP is a promising alternative HTM for efficient sDSCs and deserves further study. By comparing devices using the Ru-Z907 dye, the 10-times higher η for the D35 dye was attributed to the enhanced electron lifetime and stronger light absorption. Furthermore, the present work indicates that metal-free D-π-Α sensitizers play an important role in polymer based sDSCs.