Highly efficient, iodine-free dye-sensitized solar cells with solid-state synthesis of conducting polymers

A solid-state polymerizable conductive monomer with good conductivity and penetration to the photoelectrode is introduced to iodine-free, solid-state dye-sensitized solar cells (DSSCs) using an easily accessible and widely applicable fabrication method. A conducting polymer as a hole transporting material effectively penetrates into the TiO₂ pores and polymerizes with heating to mild temperatures. The fabricated DSSCs exhibited the highest energy conversion efficiency of 5.4% in N719 dye.