4,9-Dihydro-4,4,9,9-tetrahexyl-s-indaceno[1,2-b:5,6-b ']dithiophene as a pi-Spacer of Donor-pi-Acceptor Dye and Its Photovoltaic Performance with Liquid and Solid-State Dye-Sensitized Solar Cells

A new D-pi-A organic dye, LC-5, containing 4,9-dihydro-4,4,9,9-tetrahexyl-s-indaceno[1,2-b:5,6-b']-dithiophene as a novel pi-conjugated spacer has been synthesized and tested as a sensitizer in dye-sensitized solar cells (DSC). Volatile and ionic liquid electrolytes have been used in conjunction with the synthesized dye, and the electrolyte influence on the photovoltaic performance of DSCs was investigated. A detailed investigation, including transient photocurrent/photovoltage decay measurements and electrochemical impedance spectroscopy data, provide important conclusions about the influence of electrolytes on the photovoltaic parameters.