A series of donor-acceptor copolymers with dicyclopenta[cd,jk]pyrene and dicyclopenta[cd,lm]perylene acceptor units was prepared via palladium catalyzed cyclopenta-annulation reactions. The acceptor units were paired with diethynyl containing donor groups based on benzo[1,2-b:4,5-b']dithiophene, thieno[3,2-b]thiophene, and 4-octyl-4H-dithieno[3,2-b:2',3'-d]pyrrole to create six polymer variants. The cyclopentannulation polymerization resulted in copolymers with molecular weights (Mn) of 6-14 kDa and broad light absorption in the visible region with band gaps of 1.38-1.85 eV. The synthetic methodology, as well as optoelectronic properties, including thin-film absorption and cyclic voltammetry, of the donor-acceptor copolymers are presented.<br> <br><br>
Epsilon-near-zero thin-film metamaterials for wideband near-perfect light absorption