Photoelectric conversion element and image sensor using same

Patent metadata

Field	Value
Publication number	US-10199589-B2
Application number	US-201515534768-A
Country	US
Kind code	B2
Filing date	Dec 18, 2015
Priority date	Jan 9, 2015
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

A photoelectric conversion element, including a first electrode, a second electrode, and at least one organic layer being present between the first electrode and the second electrode, in which the organic layer contains at least two kinds of compounds having the same skeletons and different substituents in combination.

First claim

The invention claimed is:

1. A photoelectric conversion element, comprising:
a first electrode,
a second electrode, and
at least one organic layer being present between the first electrode and the second electrode,
wherein the organic layer contains a compound represented by general formula (1), and a compound represented by general formula (2):

wherein
A is a group represented by general formula (3),
B is a group selected from the group consisting of an alkoxy group, an alkylthio group, an aryl ether group, an aryl thioether group, an amino group, a furanyl group, a thiophenyl group, a pyrrolyl group, a benzofuranyl group, a benzothiophenyl group, an indolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, and a carbazolyl group,
C is an aromatic heterocyclic group containing an electron-accepting nitrogen, or a group selected from the group consisting of an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an aryl group, and a heteroaryl group, and substituted with a halogen or a cyano group, and
each of m and n represents an integer of 1 to 4, and

wherein R 1 to R 8 may be the same as or different from one another, and are each a group selected from the group consisting of a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, and an aryl group, R 1 to R 8 may form a monocyclic or condensed ring by bonding adjacent groups among R 1 to R 8 to each other,
provided that in general formula (1), B is linked at any m positions of R 1 to R 8 and a condensed ring formed by bonding any adjacent groups among R 1 to R 8 to each other, and in general formula (2), C is linked at any n positions of R 1 to R 8 and a condensed ring formed by bonding any adjacent groups among R 1 to R 8 to each other, and
further provided that in the organic layer A is the same group in the compound of general formula (1) and in the compound of general formula (2).

2. The photoelectric conversion element according to claim 1 , wherein adjacent groups among R 1 to R 8 are bonded to each other in general formula (3), and form a condensed ring including 3 to 6 rings in total.

3. The photoelectric conversion element according to claim 2 , wherein general formula (3) has a ring structure selected from among anthracene, phenanthrene, naphthacene, pyrene, chrysene, triphenylene, fluoranthene, benzofluoranthene, perylene, pentacene, and hexacene.

4. The photoelectric conversion element according to claim 2 , wherein general formula (3) has a ring structure selected from among anthracene, phenanthrene, naphthacene, pyrene, chrysene, triphenylene, fluoranthene, benzofluoranthene, perylene, and hexacene.

5. The photoelectric conversion element according to claim 2 , wherein general formula (3) has a pyrene structure.

6. The photoelectric conversion element according to claim 1 , wherein ionization potential (Ip 1 ) and electron affinity (Ea 1 ) of the compound represented by general formula (1), and ionization potential (Ip 2 ) and electron affinity (Ea 2 ) of the compound represented by general formula (2) are Ip 1 <Ip 2 and Ea 1 <Ea 2 .

7. The photoelectric conversion element according to claim 1 , wherein difference between the maximum value of an absorption spectrum of the compound represented by general formula (1) and the maximum value of an absorption spectrum of the compound represented by general formula (2) is 50 nm or less.

8. The photoelectric conversion element according to claim 1 , wherein a full width at half maximum of an absorption spectrum of the compound represented by general formula (1) and a full width at half maximum of an absorption spectrum of the compound represented by general formula (2) are both 25 nm or more to 100 nm or less.

9. The photoelectric conversion element according to claim 1 , wherein the organic layer includes a plurality of layers, and one layer among the layers contains both the compound represented by general formula (1) and the compound represented by general formula (2).

10. The photoelectric conversion element according to claim 9 , wherein the layer containing both the compound represented by general formula (1) and the compound represented by general formula (2) among the organic layers is a bulk heterojunction layer by the compounds.

11. The photoelectric conversion element according to claim 9 , wherein a mixture ratio of the compound represented by general formula (1) and the compound represented by general formula (2) is 1:3 to 3:1.

12. The photoelectric conversion element according to any claim 1 , wherein the organic layer has a film thickness of 20 nm or more to 200 nm or less.

13. The photoelectric conversion element according to claim 1 , wherein a voltage application part for applying an electric field to the organic layer is further provided.

14. The photoelectric conversion element according to claim 1 , wherein the voltage application part applies an electric field of 10 5 V/m or more to 10 9 V/m or less to the organic layer.

15. An image sensor, comprising the photoelectric conversion element according to claim 1 .

16. The image sensor according to claim 15 , wherein the image sensor includes two or more kinds of photoelectric conversion elements.

17. The image sensor according to claim 16 , wherein the two or more kinds of photoelectric conversion elements have a laminated structure.

Assignees

• Toray Industries

Inventors

• Umehara Masaaki
• Tominaga Tsuyoshi
• Kwon Jinwoo

Classifications

• C07D407/14

  containing three or more hetero rings · CPC title

• C07C255/51

  containing at least two cyano groups bound to the carbon skeleton · CPC title

• C07C255/34

  with cyano groups linked to the six-membered aromatic ring, or to the condensed ring system containing that ring, by unsaturated carbon chains · CPC title

• Y02E10/549

  Organic PV cells · CPC title

• C07D333/56

  Radicals substituted by oxygen atoms · CPC title