Photoelectric conversion element, imaging device, optical sensor, and method of using photoelectric conversion element
The present invention provides a photoelectric conversion element having a photoelectric conversion film which exhibits excellent photoelectric conversion efficiency and responsiveness, an imaging device, an optical sensor, and a method of using a photoelectric conversion element. In the photoelectric conversion element of the invention, a photoelectric conversion material contains at least one selected from the group consisting of a compound represented by General formula (1), a compound represented by General formula (2), and a compound represented by General formula (3).
1. A photoelectric conversion element in which a conductive film, a photoelectric conversion film containing a photoelectric conversion material, and a transparent conductive film are laminated in this order,
wherein the photoelectric conversion material contains at least one compound selected from the group consisting of a compound represented by General formula (1), a compound represented by General formula (2), and a compound represented by General formula (3),
(in General formula (1), each of X 1 and X 2 independently represents an oxygen atom, a sulfur atom, ═CR 1a R 1b or ═NR 1c ; each of Y 1 and Y 2 independently represents an oxygen atom, a sulfur atom, >CR 1d R 1e , or >SiR 1f R 1g ; each of R 1a to R 1g independently represents a hydrogen atom or a substituent; Q represents a group selected from the group consisting of groups represented by General formulae (4) to (8); each of R 1 and R 2 independently represents a substituent; each of R 3 to R 24 independently represents a hydrogen atom or a substituent; n represents 1; and
in General formulae (2) to (3), each of X 1 and X 2 independently represents an oxygen atom, a sulfur atom, =CR 1a R 1b or ═NR 1c ; each of Y 1 and Y 2 independently represents an oxygen atom, a sulfur atom, >CR 1d R 1e or >SiR 1f R 1g ; each of R 1a to R 1g independently represents a hydrogen atom or a substituent; Q represents a group selected from the group consisting of groups represented by General formulae (4) to (8); each of R 1 and R 2 independently represents a substituent; each of R 3 to R 24 independently represents a hydrogen atom or a substituent; n represents 0 or 1; and
when n=1, carbon atoms represented by *1 to *4 in General formulae (4) to (8) correspond to carbon atoms represented by *1 to *4 in General formulae (1) to (3), respectively; and when n=0, the compounds represented by General formulae (2) to (3) are compounds represented by General formulae (10) to (11), respectively), and
wherein in General formulae (1) to (3), at least one of R 1 and R 2 is a group represented by General formula (15),
(in General formula (15), each of R 33 to R 42 independently represents a hydrogen atom or a substituent; R 32 represents an arylene group which may have a substituent or a heteroarylene group which may have a substituent; R 37 and R 38 , R 32 and R 33 , and R 32 and R 42 may form a ring by being linked to each other; and *5 represents a bonding position).
2. The photoelectric conversion element according to claim 1 ,
wherein the photoelectric conversion material contains at least one compound selected from the group consisting of a compound represented by General formula (12) and a compound represented by General formula (13),
(in General formula (12), Q represents a group selected from the group consisting of groups represented by General formulae (4) to (8); each of R 1 and R 2 independently represents a substituent; each of R 3 to R 24 independently represents a hydrogen atom or a substituent; n represents 1, and
in General formula (13), Q represents a group selected from the group consisting of groups represented by General formulae (4) to (8); each of R 1 and R 2 independently represents a substituent; each of R 3 to R 24 independently represents a hydrogen atom or a substituent; n represents 0 or 1).
3. The photoelectric conversion element according to claim 1 ,
wherein each of R 1 and R 2 in General formulae (1) to (3) represents an aryl group which may have a substituent or a heteroaryl group which may have a substituent.
4. The photoelectric conversion element according to claim 1 ,
wherein in General formulae (1) to (3), R 1 and R 2 represent a same substituent.
5. The photoelectric conversion element according to claim 1 ,
wherein the photoelectric conversion film further contains an n-type organic compound.
6. The photoelectric conversion element according to claim 5 ,
wherein the n-type organic compound contains a fullerene-based compound selected from the group consisting of fullerenes and derivatives thereof.
7. The photoelectric conversion element according to claim 6 ,
wherein a content ratio of the fullerene-based compound to a sum of the fullerene-based compound and one or more of the compounds represented by General formulae (1) to (3) (film thickness of the fullerene-based compound expressed in terms of a single layer/(film thickness of one or more of the compounds represented by General formulae (1) to (3) expressed in terms of a single layer+film thickness of the fullerene-based compound expressed in terms of a single layer)) is equal to or greater than 50% by volume.
8. The photoelectric conversion element according to claim 1 ,
wherein a charge blocking film is disposed between the conductive film and the transparent conductive film.
9. The photoelectric conversion element according to claim 8 , comprising the conductive film, the charge blocking film, the photoelectric conversion film, and the transparent conductive film in this order, or the conductive film, the photoelectric conversion film, the charge blocking film, and the transparent conductive film in this order.
10. An imaging device comprising the photoelectric conversion element according to claim 1 .
11. An optical sensor comprising the photoelectric conversion element according to claim 1 .
12. A method of using the photoelectric conversion element according to claim 1 ,
wherein the conductive film and the transparent conductive film constitute a pair of electrodes, and an electric field of 1×10 −5 V/cm to 1×10 7 V/cm is applied between the pair of electrodes.