Optimization of dye-sensitized solar cells prepared by compression method

Nanostructured TiO 2 films have been deposited onto conducting glass and on flexible conducting plastic substrates using a compression technique. Dye-sensitized solar cells prepared from Degussa P25 TiO 2 powder, red dye (Ru(dcbpy) 2(SCN) 2) or black dye (Ru(tcterpy)(SCN) 3) and an electrolyte containing LiI and I 2 in 3-methoxypropionitrile were tested using standard photoelectrochemical techniques. The average overall efficiency of small open cells sensitized with the red dye on plastic substrates was 4.5% (100 W m −2). In a direct comparison, red and black dye gave about the same efficiencies. For both dyes, addition of 4- tert-butylpyridine to the electrolyte resulted in a decreased IPCE response in the whole spectral range, with a specific decrease in the red region, which is attributed to a shift in the conduction band edge of the nanostructured TiO 2.