V. S. Saji, K. Zong, M. Pyo
May 20, 2010
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0
Influential Citations
29
Citations
Journal
Journal of Photochemistry and Photobiology A-chemistry
Abstract
Abstract Thieno[3,4- b ]thiophene-2-carboxylic acid (TTHC) was newly synthesized and poly(thieno[3,4- b ]thiophene-2-carboxylic acid) (PTTHC), showing NIR absorption with a low band gap of 1.0 eV, was prepared by chemical or electrochemical polymerization. Vis–NIR spectroscopic studies on PTTHC adsorption revealed that the presence of pendant carboxylic groups on a polymer chain is important to obtain highly sensitized TiO 2 . The extent of PTTHC adsorption showed proportional increases as raising the adsorption temperatures, reaching saturation at the amount equivalent to a monolayer formation (this does not mean PTTHC monolayer coverage on TiO 2 ). Sequential treatments of TiO 2 revealed that the polymer can be adsorbed on N3-adsorbed TiO 2 without desorbing N3. The amounts of PTTHC adsorbed on N3-adsorbed TiO 2 with increasing adsorption temperatures implied that only a small fraction of polymer chains is involved in anchoring with most chain segments remaining unbound to TiO 2 . The dye adsorption behaviors were further studied by FTIR, EDX, and TGA. Finally, PTTHC was applied for the preparation of panchromatic dye-sensitized solar cells. The power conversion efficiency ( η ) of 1.2% for PTTHC-adsorbed TiO 2 was increased to 4.3% after N3 adsorption on PTTHC-adsorbed TiO 2 . Similar enhancement of η was observed after PTTHC treatment on N3-adsorbed TiO 2 .