Multichromophoric sensitizers based on calix[4]arene scaffold and 4H-pyranylidene moiety for DSSCs application

We have synthesized lower rim 1,3-derivatives of 4-tert-butylcalix[4]arene-appended dyes in order to test their physical and photovoltaic properties. These dyes consist in a donor group based on triphenylamine and/or 4H-pyranylidene moieties, a heteroaromatic π-conjugated spacer such a thiophene ring and an acceptor group like cyanoacetic acid. The molar extinction coefficient of these systems increases with the introduction of the second dye in the same molecule and it is observed an extended band along the visible spectrum. The use of calix[4]arene platform with other dyes could lead to a new strategy to the achievement of novel panchromatic dyes.