Polymers with low band gaps and high charge mobility

Abstract

Polymers with low band gaps and high charge mobility, as well as related systems, methods and components are disclosed.

1 . A photovoltaic cell, comprising:
 a first electrode,   a second electrode, and   a photoactive material disposed between the first and second electrodes, the photoactive material comprising an electron donor material and an electron acceptor material, the electron donor material comprises a copolymer including a first monomer repeat unit, and the first monomer repeat unit comprises a thienothiophene moiety.   
   
   
       2 . The photovoltaic cell of  claim 1 , wherein the thienothiophene moiety is optionally substituted with at least one substituent selected from the group consisting of C 1 -C 20  alkyl, C 1 -C 20  alkoxy, aryl, heteroaryl, C 3 -C 20  cycloalkyl, C 3 -C 20  heterocycloalkyl, halo, CN, NO 2 , and SO 2 R, in which R is H, C 1 -C 20  alkyl, C 1 -C 20  alkoxy, aryl, heteroaryl, C 3 -C 20  cycloalkyl, or C 3 -C 20  heterocycloalkyl. 
   
   
       3 . The photovoltaic cell of  claim 1 , wherein the thienothiophene moiety is optionally substituted with halo. 
   
   
       4 . The photovoltaic cell of  claim 1 , wherein the thienothiophene moiety is optionally substituted with fluoro. 
   
   
       5 . The photovoltaic cell of  claim 1 , wherein the electron acceptor material comprises a fullerene. 
   
   
       6 . The photovoltaic cell of  claim 1 , wherein the electron acceptor material comprises a substituted fullerene. 
   
   
       7 . The photovoltaic cell of  claim 1 , wherein the electron acceptor material comprises a PCBM.