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.

What is claimed is: 
     
         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 a polymer including a first comonomer repeat unit and a second comonomer repeat unit different from the first comonomer repeat unit, the first comonomer repeat unit comprising 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 photoactive material comprises an electron donor material and an electron acceptor material. 
     
     
         6 . The photovoltaic cell of  claim 5 , wherein the electron acceptor material comprises a fullerene. 
     
     
         7 . The photovoltaic cell of  claim 5 , wherein the electron acceptor material comprises a substituted fullerene. 
     
     
         8 . The photovoltaic cell of  claim 5 , wherein the electron acceptor material comprises a PCBM.