Synthesis and properties of anthrylene-substituted phenyleneethynylene dyes having amino/cyano group(s) and their application to dye-sensitized solar cells

A series of anthrylene-substituted phenyleneethynylene dyes having amino/cyano group(s) were prepared by repeating Sonogashira coupling between aryl halides and terminal acetylenes. In UVvis absorption spectra, the 9,10-anthrylene-substituted dyes showed a strong absorption band of which λmax was located from 502 to 521 nm and ε was more than 5.2 × 10 ⁴L mol- ¹ cm- ¹ indicating a highly expanded π-system in comparison with 1,5-anthrylene dye (λmax = 431 nm, ε= 2.6 × 10 ⁴L mol- ¹ cm- ¹). LippertMataga plots demonstrated that the amino- and cyano-substituted dyes underwent larger charge separation in the excited states. These acetylenic dyes served as sensitizers of dye-sensitized solar cell to achieve 5.0% of photo-to-current energy conversion efficiency.