Use of Thienylenevinylene and Ethynyl Molecular Bridges in Organic Dyes for Dye-Sensitized Solar Cells: Implications for Device Performance

The synthesis, full characterization, and use of a series of organic dyes with thienylenevinylene and ethynyl bridges as light-harvesting chromophores in TiO₂-based photoelectrochemical dye-sensitized solar cells are described. A maximum light-to-energy conversion efficiency of η=5.47 % under standard conditions is obtained for the organic dye denoted as FL16, which consists of an N,N-bis(4-hexyloxyphenyl)aniline donor moiety, an ethynylthieno[3,2-b]thiophene π bridge, and a 2-cyanoacrylic acid acceptor group. The device properties are investigated by charge extraction and transient photovoltage measurements.