Heteroatomic regioregular poly(3-substitutedthiophenes) for photovoltaic cells
View Patent ↗Regioregular polythiophene polymers can be used in photovoltaic applications including copolymers and blends. The polymer can comprise heteroatoms in the side groups. Better efficiencies can be achieved.
1. A photovoltaic device comprising:
a first electrode,
a second electrode,
an active layer disposed between the first and second electrodes, wherein the active layer comprises at least one p-type component and at least one n-type component, wherein the p-type component comprises at least one copolymer comprising regio-regular poly(3-substitutedthiophene) in which the 3-substituent is an alkyl moiety with an oxygen heteroatom substitution in the α-position of the 3-substituent.
2. The device according to claim 1 , wherein the copolymer further comprises a comonomer comprising an alkyl 3-substituent.
3. The device according to claim 1 , wherein the copolymer further comprises a comonomer comprising an alkyl 3-substituent present in about 5 to about 25 mole percent.
4. The device according to claim 1 , wherein the active layer further comprises a different polythiophene.
5. The device according to claim 1 , wherein the weight ratio of p-type to n-type material is about 1:1 to about 3:1, and the active layer comprises a polymer-fullerene heterojunction.
6. The device according to claim 1 , wherein the weight ratio of p-type to n-type material is about 1.5:1 to about 2.5:1.