New D-D-π-A triphenylamine-coumarin sensitizers for dye-sensitized solar cells.

Three D-D-π-A triphenylamine-coumarin sensitizers were designed and synthesized with a triphenylamine and coumarin double donor and a cyanoacrylic acid acceptor. Thiophene, bithiophene and phenylthiophene were used as π-bridges, respectively, and the effects of different π-bridges on the photophysical properties and photovoltaic performance were investigated. With the incorporation of an additional thiophene unit, the bithiophene π-bridge contributes to better light absorption and hence superior J