Photovoltaic cell with silole-containing polymer

1. An article, 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; wherein

the first comonomer repeat unit comprises a silacyclopentadithiophene moiety of formula (1)

in which each of R 1 , R 2 , R 3 , and R 4 , independently, is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, C 3 -C 20 cycloalkyl, C 1 -C 20 heterocycloalkyl, aryl, heteroaryl, halo, CN, OR, C(O)R, C(O)OR, or SO 2 R; R being H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 1 -C 20 heterocycloalkyl;

the second comonomer repeat unit comprises a silacyclopentadithiophene moiety of formula (1), a benzothiadiazole moiety, a thiadiazoloquinoxaline moiety, a cyclopentadithiophene moiety, a cyclopentadithiophene oxide moiety, a benzoisothiazole moiety, a benzothiazole moiety, a thiophene oxide moiety, a thienothiophene moiety, a thienothiophene oxide moiety, a dithienothiophene moiety, a dithienothiophene oxide moiety, a tetrahydroisoindole moiety, a fluorene moiety, a fluorenone moiety, a thiazole moiety, a selenophene moiety, a silole moiety, a thiazolothiazole moiety, a cyclopentadithiazole moiety, a naphthothiadiazole moiety, a thienopyrazine moiety, an oxazole moiety, an imidazole moiety, a pyrimidine moiety, a benzoxazole moiety, or a benzimidazole moiety; and

the article is configured as a photovoltaic cell.

2. The article of claim 1 , wherein each of R 1 and R 2 , independently, is C 1 -C 20 alkyl.

3. The article of claim 1 , wherein each of R 1 and R 2 is hexyl.

4. The article of claim 1 , wherein the second comonomer repeat unit comprises a benzothiadiazole moiety of formula (2), a thiadiazoloquinoxaline moiety of formula (3), a cyclopentadithiophene dioxide moiety of formula (4), a cyclopentadithiophene monoxide moiety of formula (5), a benzoisothiazole moiety of formula (6), a benzothiazole moiety of formula (7), a thiophene dioxide moiety of formula (8), a cyclopentadithiophene dioxide moiety of formula (9), a cyclopentadithiophene tetraoxide moiety of formula (10), a thienothiophene moiety of formula (11), a thienothiophene tetraoxide moiety of formula (12), a dithienothiophene moiety of formula (13), a dithienothiophene dioxide moiety of formula (14), a dithienothiophene tetraoxide moiety of formula (15), a tetrahydroisoindole moiety of formula (16), a thienothiophene dioxide moiety of formula (17), a dithienothiophene dioxide moiety of formula (18), a fluorene moiety of formula (19), a silole moiety of formula (20), a cyclopentadithiophene moiety of formula (21), a fluorenone moiety of formula (22), a thiazole moiety of formula (23), a selenophene moiety of formula (24), a thiazolothiazole moiety of formula (25), a cyclopentadithiazole moiety of formula (26), a naphthothiadiazole moiety of formula (27), a thienopyrazine moiety of formula (28), an oxazole moiety of formula (29), an imidazole moiety of formula (30), a pyrimidine moiety of formula (31), a benzoxazole moiety of formula (32), or a benzimidazole moiety of formula (33):

wherein

each of X and Y, independently, is CH 2 , O, or S;

each of R 5 and R 6 , independently, is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, C 3 -C 20 cycloalkyl, C 1 -C 20 heterocycloalkyl, aryl, heteroaryl, halo, CN, OR, C(O)R, C(O)OR, 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 1 -C 20 heterocycloalkyl; and

each of R 7 and R 8 , independently, 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.

5. The article of claim 4 , wherein the second comonomer repeat unit comprises a benzothiadiazole moiety of formula (2), in which each of R 5 and R 6 is H.

6. The article of claim 4 , wherein the second comonomer repeat unit comprises a thiazole moiety of formula (23), in which R 5 is hexyl.

7. The article of claim 1 , wherein the polymer further comprises a third comonomer repeat unit different from the first and second comonomer repeat units.

8. The article of claim 7 , wherein the third comonomer repeat unit comprises a thiophene moiety.

9. The article of claim 8 , wherein the thiophene moiety is unsubstituted or substituted with hexyl.

10. A polymer, comprising:

a first comonomer repeat unit comprising a silacyclopentadithiophene moiety of formula (1)

in which each of R 1 , R 2 , R 3 , and R 4 , independently, is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, C 3 -C 20 cycloalkyl, C 1 -C 20 heterocycloalkyl, aryl, heteroaryl, halo, CN, OR, C(O)R, C(O)OR, or SO 2 R; R being H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 1 -C 20 heterocycloalkyl; and

a second comonomer repeat unit different from the first comonomer repeat unit, the second comonomer repeat unit comprising a silacyclopentadithiophene moiety of formula (1), a benzothiadiazole moiety, a thiadiazoloquinoxaline moiety, a cyclopentadithiophene moiety, a cyclopentadithiophene oxide moiety, a benzoisothiazole moiety, a benzothiazole moiety, a thiophene oxide moiety, a thienothiophene moiety, a thienothiophene oxide moiety, a dithienothiophene moiety, a dithienothiophene oxide moiety, a tetrahydroisoindole moiety,a fluorenone moiety, a thiazole moiety, a selenophene moiety, a silole moiety, a thiazolothiazole moiety, a cyclopentadithiazole moiety, a naphthothiadiazole moiety, a thienopyrazine moiety, an oxazole moiety, an imidazole moiety, a pyrimidine moiety, a benzoxazole moiety, or a benzimidazole moiety.

11. The polymer of claim 10 , wherein each of R 1 and R 2 , independently, is C 1 -C 20 alkyl.

12. The polymer of claim 10 , wherein each of R 1 and R 2 is hexyl.

13. The polymer of claim 10 , wherein the second comonomer repeat unit comprises a benzothiadiazole moiety of formula (2), a thiadiazoloquinoxaline moiety of formula (3), a cyclopentadithiophene dioxide moiety of formula (4), a cyclopentadithiophene monoxide moiety of formula (5), a benzoisothiazole moiety of formula (6), a benzothiazole moiety of formula (7), a thiophene dioxide moiety of formula (8), a cyclopentadithiophene dioxide moiety of formula (9), a cyclopentadithiophene tetraoxide moiety of formula (10), a thienothiophene moiety of formula (11), a thienothiophene tetraoxide moiety of formula (12), a dithienothiophene moiety of formula (13), a dithienothiophene dioxide moiety of formula (14), a dithienothiophene tetraoxide moiety of formula (15), a tetrahydroisoindole moiety of formula (16), a thienothiophene dioxide moiety of formula (17), a dithienothiophene dioxide moiety of formula (18), a silole moiety of formula (20), a cyclopentadithiophene moiety of formula (21), a fluorenone moiety of formula (22), a thiazole moiety of formula (23), a selenophene moiety of formula (24), a thiazolothiazole moiety of formula (25), a cyclopentadithiazole moiety of formula (26), a naphthothiadiazole moiety of formula (27), a thienopyrazine moiety of formula (28), an oxazole moiety of formula (29), an imidazole moiety of formula (30), a pyrimidine moiety of formula (31), a benzoxazole moiety of formula (32), or a benzimidazole moiety of formula (33):

wherein

each of X and Y, independently, is CH 2 , O, or S;

each of R 5 and R 6 , independently, is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, C 3 -C 20 cycloalkyl, C 1 -C 20 heterocycloalkyl, aryl, heteroaryl, halo, CN, OR, C(O)R, C(O)OR, 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 1 -C 20 heterocycloalkyl; and

each of R 7 and R 8 , independently, 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.

14. The polymer of claim 13 , wherein the second comonomer repeat unit comprises a benzothiadiazole moiety of formula (2), in which each of R 5 and R 6 is H.

15. The polymer of claim 13 , wherein the second comonomer repeat unit comprises a thiazole moiety of formula (23), in which R 5 is hexyl.

16. The polymer of claim 10 , wherein the polymer further comprises a third comonomer repeat unit different from the first and second comonomer repeat units.

17. The polymer of claim 16 , wherein the third comonomer repeat unit comprises a thiophene moiety.

18. The polymer of claim 17 , wherein the thiophene moiety is unsubstituted or substituted with hexyl.