A novel hole transport material for iodine-free solid state dye-sensitized solar cells

A novel bis-EDOT-based monomer with ethylene glycol oligomers was synthesized and shown to exhibit strong ion solvation, good transport properties, and effective charge screening. These properties greatly improved J(SC) (4.2 to 7.0 mA cm(-2)) and eta (1.6 to 2.9%) in an iodine-free solid state dye-sensitized solar cell (DSSC) employing a Z-907 sensitizer, compared with the corresponding values of DSSCs fabricated using the standard bis-EDOT.