n-type Molecules and Polymers based on Perylene bisimide and thiophene moieties for photovoltaic applications.

The synthesis and characterization of a series of n-type conjugated molecules and polymers is reported along with their application as electron acceptor materials for bulk heterojunction organic solar cells. The synthesis of a series of conjugated donor-acceptor systems based on N,N'-bis(10-nonadecyl)perylene-3,4,9,10-tetracarboxylic diimide moiety substituted in bay position with dithienothiophene, bithiophene or terthiophene moieties is described. These materials are highly processable from solution, show good sunlight-harvesting and electrochemical ambipolar properties. Upon photoinduced absorption, these new materials act as acceptor respect to poly-3-hexylthiophene (P3HT). A preliminary PV characterization of these materials in bulk heterojunction solar cells with P3HT is presented. The results clearly demonstrate the potentialities of these new materials as photoactive components in organic solar cells.