Polymers with low band gaps and high charge mobility
View Patent ↗This disclosure relates to a polymer containing a first comonomer repeat unit and a second comonomer repeat unit. The first comonomer repeat unit includes a cyclopentadithiophene moiety. The second comonomer repeat unit includes a thienothiophene moiety, a thienothiophene tetraoxide moiety, a dithienothiophene moiety, a dithienothiophene dioxide moiety, a dithienothiophene tetraoxide moiety, or a tetrahydroisoindole moiety. The polymer can be used as a photoactive material in a photovoltaic cell. This disclosure also relates to such photovoltaic cells, as well as modules containing such photovoltaic cells.
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, wherein the first comonomer repeat unit comprises a cyclopentadithiophene moiety, and the second comonomer repeat unit comprises a thienothiophene moiety of formula (XI):
wherein
each of R 5 and R 6 , independently, is H, 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 or SO 2 R, in which R is C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 3 -C 20 heterocycloalkyl.
2. The photovoltaic cell of claim 1 , wherein the cyclopentadithiophene moiety is 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 2 , wherein the cyclopentadithiophene moiety is substituted with hexyl, 2-ethylhexyl, or 3,7-dimethyloctyl.
4. The photovoltaic cell of claim 2 , wherein the cyclopentadithiophene moiety is substituted at 4-position.
5. The photovoltaic cell of claim 1 , wherein the first comonomer repeat unit comprises a cyclopentadithiophene moiety of formula (I):
wherein each of R 1 , R 2 , R 3 , and R 4 , independently, is H, 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 , or 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.
6. The photovoltaic cell of claim 5 , wherein each of R 1 and R 2 , independently, is hexyl, 2-ethylhexyl, or 3,7-dimethyloctyl.
7. The photovoltaic cell of claim 1 , wherein the photovoltaic cell is a tandem photovoltaic cell.
8. A polymer, comprising:
a first comonomer repeat unit comprising a cyclopentadithiophene moiety, and
a second comonomer repeat unit comprising a thienothiophene moiety of formula (XI):
wherein
each of R 5 and R 6 , independently, is H, 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 or SO 2 R, in which R is C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 3 -C 20 heterocycloalkyl.
9. The polymer of claim 8 , wherein the cyclopentadithiophene moiety is 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.
10. The polymer of claim 9 , wherein the cyclopentadithiophene moiety is substituted with hexyl, 2-ethylhexyl, or 3,7-dimethyloctyl.
11. The polymer of claim 9 , wherein the cyclopentadithiophene moiety is substituted at 4-position.
12. The polymer of claim 8 , wherein the first comonomer repeat unit comprises a cyclopentadithiophene moiety of formula (I):
wherein each of R 1 , R 2 , R 3 , and R 4 , independently, is H, 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 , or 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.
13. The polymer of claim 12 , wherein each of R 1 and R 2 , independently, is hexyl, 2-ethylhexyl, or 3,7-dimethyloctyl.
14. 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, the first comonomer repeat unit comprising a cyclopentadithiophene moiety of formula (I):
and the second comonomer repeat unit comprising a thienothiophene moiety of formula (XI):
wherein
each of R 1 , R 2 , R 3 , and R 4 , independently, is H, 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 , or 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; and
each of R 5 and R 6 , independently, is H, 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 , or SO 2 R, in which R is C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 3 -C 20 heterocycloalkyl.
15. A polymer, comprising:
a first comonomer repeat unit comprising a cyclopentadithiophene moiety of formula (I):
a second comonomer repeat unit comprising a thienothiophene moiety of formula (XI):
wherein
each of R 1 , R 2 , R 3 , and R 4 , independently, is H, 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 , or 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; and
each of R 5 and R 6 , independently, is H, 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 , or SO 2 R, in which R is C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 3 -C 20 heterocycloalkyl.