JP5344432B2 - Photoelectric conversion element - Google Patents

Description

  The present invention relates to a photoelectric conversion element. Specifically, for example, the present invention relates to a photoelectric conversion element used for a solar cell element or an optical sensor element.

  A solar cell element is mentioned as a typical example of a device using a photoelectric conversion element. A photoelectric conversion element is called a photoelectric conversion layer in a solar cell element, and when classified roughly on the basis of a photoelectric conversion layer, an inorganic solar cell using an inorganic material such as Si or GaAs and an organic material such as a conductive polymer are used. Classified as organic solar cells.

  Examples of inorganic solar cell elements include silicon solar cell elements, etc., but they have a large number of problems such as lack of diversity and high cost because they are inorganic and have a large environmental load in the manufacturing process. Yes. In comparison, organic solar cell elements are attracting attention because they can solve the problems of inorganic solar cell elements such as low environmental load, diversity, and low cost.

Examples of organic solar cell elements include Schottky barrier solar cell elements that use a Schottky barrier generated between an organic semiconductor and a metal thin film, and dyes such as Ru supported on TiO ₂ , and dye increases with an electrolyte. Examples thereof include an organic thin-film solar cell element using an electron acceptor (hereinafter referred to as an electron transport layer) and a hole acceptor (hereinafter referred to as a hole transport layer) as a photovoltaic cell element and a photoelectric conversion layer.

  With a Schottky barrier solar cell element, an organic semiconductor and a metal thin film are joined together, and the difference between the work function of the metal and the electron affinity of the semiconductor appears in the semiconductor portion as a barrier (Schottky barrier). An element that undergoes electrification and separation when irradiated with light. However, the Schottky barrier solar cell element has a very low photoelectric conversion efficiency of 0.1% or less and is not practical.

  The dye-sensitized solar cell element is an element that undergoes electrification separation when the dye is excited by light irradiation and emits electrons. The dye-sensitized solar cell element achieves a high photoelectric conversion efficiency of 10%. However, in order to obtain high efficiency, an expensive material such as a Ru dye or a Pt electrode is necessary, and a liquid electrolyte is used. Therefore, it cannot be said that its long-term stability is excellent.

  On the other hand, organic thin-film solar cell elements are attracting attention because they are particularly easy to manufacture and low-cost compared to other solar cell elements. For example, a bilayer organic thin-film solar cell element in which a conductive polymer that also serves as an electron transporting layer and a hole transporting layer is laminated, and a conductive polymer compound that also serves as an electron transporting layer and a hole transporting layer are applied. Examples include bulk heterojunction type organic thin film solar cell elements.

  A bilayer organic thin film solar cell element is one in which a pn junction is formed at the interface between two layers by bonding a conductive polymer that also serves as an electron transport layer and a hole transport layer, thereby causing photoelectric conversion. . For example, the thing using a perylene derivative as an electron carrying layer and using copper phthalocyanine as a hole carrying layer is mentioned (patent document 1). However, in order to prevent the recombination of carriers and observe the current, the film thickness needs to be about 20 nm. At this film thickness, light absorption is insufficient and the photoelectric conversion efficiency is 1% or less.

  On the other hand, the bulk heterojunction organic thin-film solar cell element has a single-layer structure of an electron-hole transport layer in which a conductive polymer serving as both an electron transport layer and a hole transport layer is mixed. In this case, the pn junction at the molecular level can increase the volume involved in photoelectric conversion. For example, a polythiophene-based conjugated polymer is used, and a fullerene derivative [6,6] -phenyl-C61 butyric acid methyl ester (PCBM) is used as an electron transport layer (Patent Document 2). This greatly improved the photoelectric conversion efficiency, but if the film thickness was increased to increase the amount of light absorption, the probability of disappearance due to carrier recombination increased, and the conversion efficiency was still insufficient. .

  In addition, as the electron transport layer of the photoelectric conversion element, as the one in which a fulleropyrrolidine derivative is used, for example, N-alkyl-2-phenyl [60] fulleropyrrolidine (Patent Documents 3, 4, and 5), N -Phenyl-2-alkyl [60] fulleropyrrolidine (Patent Documents 6 and 7), N-alkyl-2- (Substituent capable of electrolytic polymerization such as thiophenyl, pyrrolinyl, furanyl) [60] Fulleropyrrolidine (Patent Document 8) 9), N-polyethylene oxide-2-phenyl [60] fulleropyrrolidine (Patent Document 10), etc., but none of them has sufficient photoelectric conversion efficiency.

  As described above, various studies have been made as organic thin-film solar cell elements. However, since no electron transport layer having good characteristics has been found since PCBM, and a solar cell having insufficient electron transport capability, I can't expect conversion efficiency. That is, development of an electron acceptor having a high electron transport capability is indispensable for improving the photoelectric conversion efficiency of the organic thin film solar cell element.

JP 2006-302925 A JP 2006-245073 A JP 2008-135479 A JP 2007-251086 A JP 2009-067708 A JP 2008-247934 A JP 2007-202029 A JP 2007-258079 A JP 2007-0671115 A JP 2009-084264 A

  This invention is providing the photoelectric conversion element which the photoelectric conversion efficiency improved by having an electron acceptor which has high electron transport ability.

［Ｒ^１は下記一般式（７）〜（１４）に示される基からなる群より選ばれる基であって、Ｒ^２は芳香環を１つ含んでなる炭素数６〜１６の有機基である。また、フラーレン部位はＣ_６０、Ｃ_７０、Ｃ_７６およびＣ_８４からなる群より選ばれるフラーレン類である。］

［式中、Ｒ^８は炭素数１〜１６の直鎖もしくは分枝鎖の２価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基、及び炭素数６〜１６の２価の芳香族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された芳香族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基であり、Ｒ^１０は炭素数１〜１６の直鎖もしくは分枝鎖の１価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基、及び炭素数６〜１６の１価の芳香族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された芳香族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基であり、Ｒ^９は水素原子、及び炭素数１〜１６の直鎖もしくは分枝鎖の１価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基、及び炭素数６〜１６の１価の芳香族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された芳香族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基であり、Ｒ^１１及びＲ^１２は炭素数２〜４の直鎖もしくは分枝鎖の２価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基であり、Ｒ^１３は水素原子、及び炭素数２〜４の直鎖もしくは分枝鎖の１価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基である。ｍおよびａは１〜３の整数を示し、ｎおよびｂは０〜３の整数を示す。］
また、本発明は、基板（Ｔ）上に形成された２つの電極（Ｙ）間に、導電性高分子（ｄ）と電子受容体（ａ）を含有する光電変換層（Ｅ）を有する光電変換素子（Ｐ）であって、該電子受容体（ａ）が、下記一般式（３）または下記一般式（４）で示されるフラーロピロリジン誘導体（Ｆ２）を含有することを特徴とする、光電変換素子（Ｐ）である。

［式中、Ｒ^１は一般式（２５）で示される基であって、Ｒ^３〜Ｒ^７はそれらのうち少なくとも一つが一般式（１５）〜（２６）で示される基からなる群より選ばれる基であり、それ以外は水素原子である。また、フラーレン部位はＣ_６０、Ｃ_７０、Ｃ_７６及びＣ_８４からなる群より選ばれるフラーレン類である。］

［式中、Ｒ^１４〜Ｒ^１８は炭素数１〜１６の直鎖もしくは分枝鎖の２価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基、及び炭素数６〜１６の2価の芳香族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された芳香族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基であり、Ｒ^１９〜Ｒ^２２は炭素数２〜４の直鎖もしくは分枝鎖の２価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基であり、Ｒ^２３〜Ｒ^３６は水素原子、または炭素数１〜１６の直鎖もしくは分枝鎖の１価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基、及び１価の炭素数６〜１６の芳香族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された芳香族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基である。ｍ’およびａ’は１〜３の整数を示し、ｎ’およびｂ’は０〜３の整数を示す。］
また、本発明は、基板（Ｔ）上に形成された２つの電極（Ｙ）間に、導電性高分子（ｄ）と電子受容体（ａ）を含有する光電変換層（Ｅ）を有する光電変換素子（Ｐ）であって、該電子受容体（ａ）が、下記一般式（５）または下記一般式（６）で示されるフラーロピロリジン誘導体（Ｆ３）を含有することを特徴とする、光電変換素子（Ｐ）である。

［Ｒ^１は下記一般式（２７）に示される基からなる群より選ばれる基であって、Ｒ^２は芳香環を１つ含んでなる炭素数６〜１６の有機基である。また、フラーレン部位はＣ_６０である。］

［Ｒ^３７は炭素数２〜１６の直鎖もしくは分枝鎖の１価の脂肪族炭化水素基、及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基、及び炭素数６〜１６の１価の芳香族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された芳香族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基である。］ The inventors of the present invention have reached the present invention as a result of studies to achieve the above object.
That is, the present invention provides a photoelectric conversion layer having a photoelectric conversion layer (E) containing a conductive polymer (d) and an electron acceptor (a) between two electrodes (Y) formed on a substrate (T). A conversion element (P), wherein the electron acceptor (a) contains a fulleropyrrolidine derivative (F1) represented by the following general formula (1) or the following general formula (2): It is a photoelectric conversion element (P).

[R ¹ is a group selected from the group consisting of groups represented by the following general formulas (7) to (14), and R ² is an organic group having 6 to 16 carbon atoms including one aromatic ring. . The fullerene moiety is a fullerene selected from the group consisting of C ₆₀ , C ₇₀ , C ₇₆ and C ₈₄ . ]

[In the formula, R ⁸ represents an aliphatic (semi) par in which a linear or branched divalent aliphatic hydrocarbon group having 1 to 16 carbon atoms and a part or all of its hydrogen atoms are substituted with fluorine atoms. A group consisting of a fluorohydrocarbon group, a divalent aromatic hydrocarbon group having 6 to 16 carbon atoms, and an aromatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms R ¹⁰ is a linear or branched monovalent aliphatic hydrocarbon group having 1 to 16 carbon atoms and an aliphatic group in which part or all of the hydrogen atoms are substituted with fluorine atoms (semi ) A perfluorohydrocarbon group, a monovalent aromatic hydrocarbon group having 6 to 16 carbon atoms, and an aromatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms a group selected from the group, R ⁹ is A C1-C16 linear or branched monovalent aliphatic hydrocarbon group and an aliphatic (semi) perfluorohydrocarbon in which part or all of the hydrogen atoms are substituted with fluorine atoms And a group selected from the group consisting of a monovalent aromatic hydrocarbon group having 6 to 16 carbon atoms and an aromatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms R ¹¹ and R ¹² are each an aliphatic (semi-carbon) having a linear or branched divalent aliphatic hydrocarbon group having 2 to 4 carbon atoms and part or all of the hydrogen atoms substituted with fluorine atoms. ) R ¹³ is a group selected from the group consisting of perfluorohydrocarbon groups, and R ¹³ is a hydrogen atom, a linear or branched monovalent aliphatic hydrocarbon group having 2 to 4 carbon atoms, and part or all thereof. Hydrogen atom was replaced by fluorine atom Aliphatic (semi) a group selected from the group consisting of perfluoro hydrocarbon group. m and a show the integer of 1-3, n and b show the integer of 0-3. ]
The present invention also provides a photoelectric conversion layer (E) having a conductive polymer (d) and an electron acceptor (a) between two electrodes (Y) formed on a substrate (T). A conversion element (P), wherein the electron acceptor (a) contains a fulleropyrrolidine derivative (F2) represented by the following general formula (3) or the following general formula (4): It is a photoelectric conversion element (P).

[Wherein, R ¹ is a group represented by the general formula (25), and R ^{3 to} R ⁷ are selected from the group consisting of at least one of the groups represented by the general formulas (15) to (26). The other group is a hydrogen atom. The fullerene moiety is a fullerene selected from the group consisting of C ₆₀ , C ₇₀ , C ₇₆ and C ₈₄ . ]

[Wherein, R ^{14 to} R ¹⁸ represent a linear or branched divalent aliphatic hydrocarbon group having 1 to 16 carbon atoms and an aliphatic group in which part or all of the hydrogen atoms are substituted with fluorine atoms ( From a semi) perfluorohydrocarbon group, a divalent aromatic hydrocarbon group having 6 to 16 carbon atoms and an aromatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms. R ^{19 to} R ²² are groups selected from the group consisting of C 2-4 linear or branched divalent aliphatic hydrocarbon groups and part or all of the hydrogen atoms are substituted with fluorine atoms Is a group selected from the group consisting of an aliphatic (semi) perfluorohydrocarbon group, and R ^{23 to} R ³⁶ are a hydrogen atom, or a linear or branched monovalent aliphatic group having 1 to 16 carbon atoms. A hydrocarbon group and some or all of its hydrogen atoms Aliphatic (semi) perfluorohydrocarbon groups substituted with fluorine atoms, monovalent aromatic hydrocarbon groups having 6 to 16 carbon atoms, and aromatics in which part or all of the hydrogen atoms are substituted with fluorine atoms It is a group selected from the group consisting of (semi) perfluorohydrocarbon groups. m ′ and a ′ represent an integer of 1 to 3, and n ′ and b ′ represent an integer of 0 to 3. ]
The present invention also provides a photoelectric conversion layer (E) having a conductive polymer (d) and an electron acceptor (a) between two electrodes (Y) formed on a substrate (T). In the conversion element (P), the electron acceptor (a) contains a fulleropyrrolidine derivative (F3) represented by the following general formula (5) or the following general formula (6): It is a photoelectric conversion element (P).

[R ¹ is a group selected from the group consisting of groups represented by the following general formula (27), and R ² is an organic group having 6 to 16 carbon atoms containing one aromatic ring. Furthermore, the fullerene part is _{C 60.} ]

[R ³⁷ is a linear or branched monovalent aliphatic hydrocarbon group having 2 to 16 carbon atoms, and an aliphatic (semi) perfluorocarbonized carbon in which part or all of the hydrogen atoms are substituted with fluorine atoms. Selected from the group consisting of a hydrogen group, a monovalent aromatic hydrocarbon group having 6 to 16 carbon atoms, and an aromatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms. It is a group. ]

  In the present invention, by using a fulleropyrrolidine derivative as the electron acceptor (electron transport layer), the electron transport property is improved and high photoelectric conversion efficiency can be achieved.

It is a schematic sectional drawing which shows an example of the photoelectric conversion element of this invention.

(T) Substrate (Y) Electrode (i-1) Hole extraction layer (E) Photoelectric conversion layer (i-2) Electron extraction layer

  The photoelectric conversion element of the present invention is a photoelectric conversion in which a photoelectric conversion layer containing a conductive polymer and an electron acceptor containing a fulleropyrrolidine derivative (F) is provided between two electrodes formed on a substrate. It is an element. The fulleropyrrolidine derivative (F) includes (F1), (F2), and (F3) described below.

  The fulleropyrrolidine derivative (F1) is represented by the above general formula (1) or general formula (2).

In (F1), R ¹ is a group represented by the above general formulas (7) to (14). Among these, general formulas (7) to (9) are preferable, and among these, general formula (7) is preferable. Particularly preferred. In General Formula (7), R ⁸ is preferably an aliphatic group having 1 to 8 carbon atoms, and R ⁹ is preferably an aliphatic group having 1 to 8 carbon atoms.

R ² is an organic group having 6 to 16 carbon atoms containing one aromatic ring. When the number of carbon atoms is 17 or more, the electron transport ability of the fullerene derivative is lowered, which is not preferable.

The fullerene moiety in the phenylfulleropyrrolidine derivative (F1) is a fullerene selected from the group consisting of C ₆₀ , C ₇₀ , C ₇₆ and C _84. From the viewpoint of the frontier orbital and the viewpoint of the electron transport ability, ₆₀ is more preferable.

  The fulleropyrrolidine derivative (F2) is represented by the above general formula (3) and general formula (4).

In (F2), R ¹ is a group represented by the general formula (25). m ′ represents an integer of 1 to 3, preferably 1, and n ′ represents an integer of 0 to 3, preferably 1. When m ′ is 4 or more, the electron transport ability is lowered, which is not preferable. When n ′ is 4 or more, the electron transport ability is lowered, which is not preferable.
R ^{3 to} R ⁷ are groups in which at least one of them is selected from the group consisting of the groups represented by the general formulas (15) to (26), and among these, (24) is preferable from the viewpoint of electron transport ability. The rest are hydrogen atoms.
The fullerene moiety in the phenylfulleropyrrolidine derivative (F2) is a fullerene selected from the group consisting of C ₆₀ , C ₇₀ , C ₇₆ and C _84. From the viewpoint of frontier orbital and from the viewpoint of electron transport ability, C ₆₀ is more preferable.

  The fulleropyrrolidine derivative (F3) is represented by the above general formula (5) and general formula (6).

In (F3), R ¹ is a group represented by the general formula (27). In the general formula (27), R ³⁷ is a monovalent aliphatic hydrocarbon group, and aliphatic its some or all hydrogen atoms are substituted with fluorine atoms, straight-chain or branched-chain having 2 to 16 carbon atoms (Semi) perfluorohydrocarbon group, monovalent aromatic hydrocarbon group having 6 to 16 carbon atoms, and aromatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms Among them, an aliphatic hydrocarbon group having 4 to 8 carbon atoms is preferable from the viewpoint of solubility in a solvent.
R ² is an organic group having 6 to 16 carbon atoms containing one aromatic ring, and is preferably a group represented by the following general formula (28). In the general formula (28), R ^{3 to} R ⁷ are hydrogen atoms, groups selected from the group consisting of groups represented by the above general formulas (15) to (26), general formula (27) or the following general formula (29). Is preferred.
Further, the fullerene part of the (F3) is _{C 60.}

［式中、Ｒ^３〜Ｒ^７は水素原子、上記一般式（１５）〜（２６）、一般式（２７）または下記一般式（２９）で示される基からなる群より選ばれる基である。］

[Wherein, R ^{3 to} R ⁷ are a hydrogen atom, a group selected from the group consisting of groups represented by the general formulas (15) to (26), the general formula (27), or the following general formula (29). ]

［式中、Ｒ^３８は水素原子、または炭素数１〜１６の直鎖もしくは分枝鎖の１価の脂肪族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された脂肪族（セミ）パーフルオロ炭化水素基、及び１価の炭素数６〜１６の芳香族炭化水素基及びその一部または全部の水素原子がフッ素原子で置換された芳香族（セミ）パーフルオロ炭化水素基からなる群より選ばれる基である。］

[In the formula, R ³⁸ represents a hydrogen atom, or a linear or branched monovalent aliphatic hydrocarbon group having 1 to 16 carbon atoms and an aliphatic group in which part or all of the hydrogen atoms are substituted with fluorine atoms. (Semi) perfluorohydrocarbon group, monovalent aromatic hydrocarbon group having 6 to 16 carbon atoms, and aromatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms A group selected from the group consisting of ]

Among the above-mentioned fulleropyrrolidine derivatives (F), one that is preferably used is (F1), and among them, the fulleropyrrolidine derivative (F11) in which R ² is represented by the general formula (28) is more preferable.

Of the substituents of the fulleropyrrolidine derivative (F11), those preferably used as R1 are groups selected from the group consisting of groups represented by the general formulas (7) to (9), and R ^{3 to} R ⁷ A group selected from a hydrogen atom, general formulas (25) to (26), and general formula (29) is preferred, and at least two of R ^{3 to} R ⁷ are preferably hydrogen atoms.

The fullerene part of the fulleropyrrolidine derivative (F11) is more preferably C ₆₀ from the viewpoint of frontier orbitals.

Method for Producing Fulleropyrrolidine Derivative (F) A solution (for example, a toluene solution) in which, for example, 2-3 equivalents of substituted benzaldehyde and 1-2 equivalents of fullerene are added to 1 equivalent of N-substituted glycine. For example, the phenyl fulleropyrrolidine derivative (F) can be obtained by refluxing for 16 to 35 hours.
The specific production method is performed by the method described in Journal of Organic Chemistry, 2001, 66, 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100. Can do.

  The photoelectric conversion element of the present invention comprises a photoelectric conversion layer (E) containing a conductive polymer (d) and an electron acceptor (a) between two electrodes (Y) formed on a substrate (T). A photoelectric conversion element (P). As an example, FIG. 1 shows a schematic sectional view of a typical structure thereof. Details of each component will be described below.

(1) Substrate (T)
The substrate in the present invention will be described. The substrate may be either transparent or opaque, but a transparent substrate is desirable when the substrate surface is a photoreceptor. As this transparent substrate, a substrate excellent in moisture and gas barrier properties, solvent resistance, weather resistance and the like entering from the outside of the photoelectric conversion element is desirable. For example, a rigid plate such as quartz glass, a flexible resin such as a transparent resin film, etc. A substrate is mentioned. Furthermore, in the present invention, a flexible substrate is desirable from the viewpoint of excellent workability, low cost, and light weight. Examples of the transparent resin film include polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, polyethylene, polyvinylidene fluoride, polyimide, and polymethyl methacrylate.

(2) Electrode (Y)
Then, the electrode in this invention is demonstrated.
The electrode may or may not be layered on the substrate (T), but is preferably layered. The electrode does not necessarily have translucency, but when the electrode is layered on the substrate (T), it is preferable that at least one of the electrodes has translucency. It is preferable that the electrode is composed of two layers and has two layers. Any electrode may be used as long as it has conductivity, and it is formed by sputtering, ion plating, or the like. As the light transmissive electrode, a metal thin film made of a conductive transparent material such as indium-tin composite oxide (ITO), fluorine-doped SnO ₂ (FTO), SnO ₂ is preferable, and as the light shielding electrode, an alkali metal, Metal thin films such as alkaline earth metals are preferred. Although the thickness of this electrode is not specifically limited, For example, it is about 80-100 nm.

(3) Photoelectric conversion layer (E)
Then, the photoelectric converting layer used for this invention is demonstrated. The photoelectric conversion layer in the present invention contains a conductive polymer (d) and an electron transport layer (electron acceptor) (a), and preferably also serves as a hole transport layer (hole acceptor) (s). A conductive polymer (d) and an electron transport layer (electron acceptor) (a).
The form of the conductive polymer and the electron transport layer (electron acceptor) contained is not particularly limited, but is preferably a single layer structure of an electron hole transport layer in which both are mixed, that is, a bulk heterojunction. It is. By adopting this structure, a pn junction at the molecular level becomes possible, and thus an effect of increasing the volume involved in photoelectric conversion can be obtained.
The photoelectric conversion layer (E) as described above can be obtained by removing the solvent from the mixed solution of the conductive polymer (d) and the electron acceptor (a).

In the present invention, the electron transport layer (electron acceptor) contains at least the fulleropyrrolidine derivative (F). By using this, electron transport property improves and high photoelectric conversion efficiency is obtained.
The reason is estimated as follows.
(I) The electron acceptor (electron transport layer) of the present invention has a small LUMO gap with a conductive polymer and a sufficiently high electron movement speed from the viewpoint of frontier orbitals.
(Ii) The electron acceptor (electron transport layer) of the present invention has good compatibility with the conductive polymer and sufficient bulk heterojunction density.

  As described above, the conductive polymer (d) preferably functions as a hole transport layer (hole acceptor) (s), and examples thereof include polythiophene and polyfluorene. On the other hand, the electron transport layer (electron acceptor) is preferably a fulleropyrrolidine derivative, or a mixture of two or more of a fulleropyrrolidine derivative and an arbitrary electron transport layer (electron acceptor). As a fullerene derivative.

  In the present invention, as the weight ratio of the conductive polymer (d) and the electron transport layer (electron acceptor) (a) used in the above-described photoelectric conversion layer, an electron hole transport layer having good electron transport ability is formed. Although not particularly limited, for example, (d) / (a) = 1/10 to 1 / 0.4 is preferable, and the mixing ratio is appropriately changed depending on the combination of other constituent material types. Things are preferable.

  The electron acceptor (a) may further contain a fullerene derivative (G) other than the fulleropyrrolidine derivative (F). The fullerene derivative (G) includes fullerene, PCBM, etc. The weight ratio of the fulleropyrrolidine derivative (F) and the fullerene derivative (G) is to form an electron hole transport layer having a good electron transport ability. Although it is not particularly limited, for example, (F) / (G) = 5/0 to 4/1 is preferable, and it is preferable to appropriately change to an optimal mixing ratio depending on the combination of other constituent material types. .

  In the present invention, the film thickness of the above-described photoelectric conversion layer is not particularly limited, and any film thickness may be used. However, if the film thickness is too thin, the film is short-circuited, and if it is too thick, the film resistance becomes high. Therefore, the film thickness used for a general photoelectric conversion element is preferable, for example, 20 to 800 nm.

  In the present invention, the method for forming the photoelectric conversion layer described above is not particularly limited as long as it can be uniformly formed in a predetermined film thickness, and any method may be used. For example, a spin coating method or a die coating method can be used.

  In the present invention, the number of the photoelectric conversion layers described above may be one layer or a plurality of layers, and is not particularly limited. For example, 1 to 5 layers are preferable.

(5) Other structure The other structure used for this invention is demonstrated. A charge extraction layer (i) may be formed in the photoelectric conversion element of the present invention for the purpose of promoting the movement of charges.
The compound and the number of layers are not particularly limited. For example, as the hole extraction layer (i-1), poly (styrene sulfonate) / poly (2,3-dihydrothieno [3,4- b] -1,4-dioxin) (hereinafter referred to as “PEDOT / PSS”) and the electron extraction layer (i-2) include titanium dioxide (hereinafter referred to as TiO _x ).

  When the photoelectric conversion element (P) of the present invention is used as a solar cell element (S), a conductive polymer (d) and an electron acceptor are interposed between two electrodes (Y) formed on the substrate (T). It is a solar cell element (S) which has the photoelectric converting layer (E) containing a body (a), The structure etc. which were demonstrated by the said photoelectric converting element (P) are preferable.

  When the solar cell element (S) of the present invention is used as a tandem solar cell element (S1), those described for the solar cell element (S) are preferable. In addition, the number of stacked layers is not particularly limited. For example, the number of stacked layers is about 1 to 5, and the connection state of each solar cell element (S) may be either parallel or series. Are preferably in parallel, and in order to increase the voltage to be extracted, series is preferable.

  When the photoelectric conversion element (P) of the present invention is used as an optical sensor element (U), a conductive polymer (d) and an electron acceptor are disposed between two electrodes (Y) formed on a substrate (T). It is an optical sensor element (U) having a photoelectric conversion layer (E) containing (a), and those described in the above-mentioned photoelectric conversion element (P) are preferable.

EXAMPLES Hereinafter, although an Example demonstrates this invention in more detail, this invention is not limited to this.
Hereinafter, unless otherwise specified, “parts” and “wt” mean “parts by weight” and% means% by weight.

(Production Example 1)
As a fulleropyrrolidine derivative, N- (hexyl) -2- (para (dimethylamino)) phenyl [60] fulleropyrrolidine (hereinafter referred to as HPmaPFP; compound represented by the general formula (30)) (F3-1) Was synthesized.

Synthesis of HPmaPFP (general formula (30)) 1.50 g of glycine (manufactured by Wako Pure Chemical Industries, Ltd.), 1.21 g of sodium hydroxide, di-t-butyl dicarbonate (hereinafter referred to as Boc ₂ O) 6.55 g (Wako Pure Chemical Industries, Ltd.) was dissolved in 60 ml of a dioxane / water = 1/1 (volume ratio) solution, and the solution was stirred at 25 ° C. for 24 hours, and dioxane was distilled off under reduced pressure. A 1M aqueous potassium hydrogen sulfate solution was added to the residue to adjust the pH to 3, and the aqueous layer was extracted with ethyl acetate to obtain 3.32 g of Boc-glycine (hereinafter referred to as Boc-Gly). This synthesis method was based on the method described in Journal of Organic Chemistry, 2006, No. 71, pages 2014-2020.
Boc-Gly 3.32 g, Boc ₂ O 8.53 g, 4-dimethylaminopyridine (hereinafter referred to as DMAP) 0.695 g (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 70 ml of t-butyl alcohol, The solution was stirred at 25 ° C. for 5 hours. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; ethyl acetate) to obtain 4.21 g of ^t -butyl ester of Boc-glycine (hereinafter referred to as Boc-Gly-O ^t Bu). . This synthesis method was based on the method described in Synthesis, 1994, pp. 1063-1066.

2.50 g of Boc-Gly-O ^t Bu, 0.389 g of sodium hydride (manufactured by Wako Pure Chemical Industries, Ltd.), 2.68 g of 1-bromohexane (manufactured by Wako Pure Chemical Industries, Ltd.) are added to 27 ml of dimethylformamide. After that, the solution was stirred at 55 ° C. for 1.5 hours. After adding 50 ml of saturated aqueous ammonium chloride solution, the aqueous layer was extracted with ethyl acetate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent; ethyl acetate), and N- (hexyl) Boc glycine. 2.22 g of t-butyl ester (hereinafter referred to as H-Boc-Gly-O ^t Bu) was obtained. This synthesis method was based on the method described in Bioorganic & medicinal chemistry, 2007, No. 15, pp. 2092-2105.

After dissolving 2.22 g of H-Boc-Gly-O ^t Bu in 100 ml of trifluoroacetic acid / chloroform = 1/1 (volume ratio), the solution was stirred at 25 ° C. for 20 hours. The solvent was distilled off under reduced pressure to obtain 1.90 g of N- (hexyl) glycine-trifluoroacetate (hereinafter referred to as H-Gly · TFA). This synthesis method was based on the method described in Journal of Organic Chemistry, 1990, No. 55, pages 5017-5025.
153 mg of H-Gly.TFA, 64 mg of triethylamine (manufactured by Wako Pure Chemical Industries, Ltd.), 209 mg of 4-dimethylaminobenzaldehyde (manufactured by Wako Pure Chemical Industries, Ltd.), 500 mg of fullerene [C60] (manufactured by Wako Pure Chemical Industries, Ltd.) After dissolving in 200 ml of toluene, the solution was stirred at 120 ° C. for 16 hours. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent: chloroform) to obtain 102 mg of phenylfulleropyrrolidine derivative HPmaPFP. This synthesis method was based on the method described in Journal of Organic Chemistry, 2001, 66, pages 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100.

(Production Example 2)
As a fulleropyrrolidine derivative, N- (2- (2-methoxyethoxy) ethyl) -2- (para-N-acetamido) phenyl [60] fulleropyrrolidine (hereinafter referred to as MeeAaPFP, represented by the general formula (31) Compound) (F2-1) was synthesized.

Synthesis of MeeAaPFP (general formula (31)) The same applies until the synthesis of Boc-Gly-O ^t Bu in Production Example 1.
2.50 g of Boc-Gly-O ^t Bu, 0.389 g of sodium hydride (manufactured by Wako Pure Chemical Industries, Ltd.), 2.97 g of 1-bromo-2- (2-methoxyethoxy) ethane (Sigma Aldrich Japan Co., Ltd.) ) Was dissolved in 27 ml of dimethylformamide, and the solution was stirred at 55 ° C. for 1.5 hours. After adding 50 ml of saturated aqueous ammonium chloride solution, the aqueous layer was extracted with ethyl acetate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent; ethyl acetate), and N- (2- (2- 2.81 g of methoxyethoxy) ethyl) Bocated glycine-t-butyl ester (hereinafter referred to as Mee-Boc-Gly-O ^t Bu) was obtained. This synthesis method was based on the method described in Bioorganic & medicinal chemistry, 2007, No. 15, pp. 2092-2105.

After dissolving 2.81 g of Mee-Boc-Gly-O ^t Bu in 100 ml of trifluoroacetic acid / chloroform = 1/1 (volume ratio), the solution was stirred at 25 ° C. for 20 hours. The solvent was distilled off under reduced pressure to obtain 2.02 g of N- (2- (2-methoxyethoxy) ethyl) glycine-trifluoroacetate (hereinafter referred to as Mee-Gly · TFA). This synthesis method was based on the method described in Journal of Organic Chemistry, 1990, No. 55, pages 5017-5025.
Mee-Gly.TFA 163 mg and triethylamine 64 mg (manufactured by Wako Pure Chemical Industries, Ltd.), 4- (acetamido) benzaldehyde 229 mg (manufactured by Wako Pure Chemical Industries, Ltd.), fullerene [C60] 500 mg (manufactured by Wako Pure Chemical Industries, Ltd.) Was dissolved in 200 ml of toluene, and the solution was stirred at 120 ° C. for 16 hours. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent: chloroform) to obtain 130 mg of phenylfulleropyrrolidine derivative MeeAaPFP. This synthesis method was based on the method described in Journal of Organic Chemistry, 2001, 66, pages 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100.

(Production Example 3)
As a fulleropyrrolidine derivative, N-benzyl-2- (paramethoxycarbonyl) phenyl [60] fulleropyrrolidine (hereinafter referred to as BPmcPFP, a compound represented by the general formula (32)) (F3-2) was synthesized.

Synthesis of BPmcPFP (general formula (32)) The same applies until synthesis of Boc-Gly-O ^t Bu in Production Example 1.
2.50 g of Boc-Gly-O ^t Bu, 0.389 g of sodium hydride (manufactured by Wako Pure Chemical Industries, Ltd.) and 2.78 g of benzyl bromide (manufactured by Wako Pure Chemical Industries, Ltd.) were dissolved in 27 ml of dimethylformamide. Thereafter, the solution was stirred at 55 ° C. for 1.5 hours. After adding 50 ml of a saturated aqueous ammonium chloride solution, the aqueous layer was extracted with ethyl acetate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent; ethyl acetate), and N-benzyl Boc-glycine-t. -2.26 g of butyl ester (hereinafter referred to as B-Boc-Gly-O ^t Bu) was obtained. This synthesis method was based on the method described in Bioorganic & medicinal chemistry, 2007, No. 15, pp. 2092-2105.

After dissolving 2.26 g of B-Boc-Gly-O ^t Bu in 100 ml of trifluoroacetic acid / chloroform = 1/1 (volume ratio), the solution was stirred at 25 ° C. for 20 hours. The solvent was distilled off under reduced pressure to obtain 1.94 g of N-benzylglycine-trifluoroacetate (hereinafter referred to as B-Gly · TFA). This synthesis method was based on the method described in Journal of Organic Chemistry, 1990, No. 55, pages 5017-5025.
B-Gly.TFA 156 mg, triethylamine 64 mg (manufactured by Wako Pure Chemical Industries, Ltd.), methyl 4-formylbenzoate 230 mg (manufactured by Wako Pure Chemical Industries, Ltd.), fullerene [C60] 500 mg (manufactured by Wako Pure Chemical Industries, Ltd.) Was dissolved in 200 ml of toluene, and the solution was stirred at 120 ° C. for 16 hours. After distilling off the solvent under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent: chloroform) to obtain 101 mg of phenylfulleropyrrolidine derivative BPmcPFP. This synthesis method was based on the method described in Journal of Organic Chemistry, 2001, 66, pages 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100.

(Comparative Production Example 4)
As a fulleropyrrolidine derivative, N-methyl-2- (paramethyl) phenyl [60] fulleropyrrolidine (hereinafter referred to as MPmPFP, a compound represented by the general formula (33)) was synthesized.

Synthesis of MPmPFP (general formula (33)) N-methyl-Gly 185 mg (manufactured by Wako Pure Chemical Industries, Ltd.) and 4-methylbenzaldehyde 169 mg (manufactured by Wako Pure Chemical Industries, Ltd.), fullerene [C60] 500 mg (Wako Pure Chemical Industries, Ltd.) Was added to 200 ml of toluene, and the solution was stirred at 120 ° C. for 16 hours. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; chloroform) to obtain 95 mg of phenylfulleropyrrolidine derivative MPmPFP. This synthesis method was based on the method described in Journal of Organic Chemistry, 2001, 66, pages 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100.

(Production Example 5)
As a fulleropyrrolidine derivative, N- (n-2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluorononyloxy Carbonyl) methyl-2-phenyl [60] fulleropyrrolidine (hereinafter referred to as FnNcmPFP; compound represented by general formula (34)) (F1-1) was synthesized.

Synthesis of FnNcmPFP (general formula (34)) 2.50 g of glycine (manufactured by Wako Pure Chemical Industries, Ltd.) and 7.60 g of p-toluenesulfonic acid monohydrate (manufactured by Wako Pure Chemical Industries, Ltd.) , 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 9-heptadecafluoro-1-noninol 14.99 g (manufactured by Wako Pure Chemical Industries, Ltd.) After being dissolved in a mixed solution of 80 ml and toluene, the solution was heated to 130 ° C. and stirred for 14 hours while removing generated water by an azeotropic method using a Dean-Stark apparatus. Glycine-2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluoro-1-nonyl ester p-toluenesulfone 23.70 g of acid salt (hereinafter referred to as Gly-OF ⁿ Nonyl · TSA) Obtained. This synthesis method was based on the method described in Tetrahedron, 1926, No. 71, pages 79-80.
Gly-OF ⁿ Nonyl / TSA 16.03 g, N-ethyldiisopropylamine 7.67 g (manufactured by Wako Pure Chemical Industries, Ltd.) and benzyl bromoacetate 4.35 g (manufactured by Wako Pure Chemical Industries, Ltd.) were dissolved in 28 ml of tetrahydrofuran. The solution was then stirred at 70 ° C. for 18 hours. 71 ml of ethyl acetate was added, and the organic layer was washed 3 times with 24 ml of 1M aqueous potassium hydrogen sulfate solution and twice with saturated brine, then anhydrous magnesium sulfate was added, and the mixture was allowed to stand at 25 ° C. for 3 hours. After anhydrous magnesium sulfate was filtered off and the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; ethyl acetate: hexane = 1: 1), and N-aspartic acid ^α 2,2,3,3 4,4,5,5,6,6,7,7,8,8,9,9,9- heptadecafluoro-1-nonyl ester ^beta-benzyl ester ^{(hereinafter, Nasp (α OF n nonyl)} - β OBzl This gave 6.22 g. This synthesis method was based on the method described in Journal of peptide science, 2004, No. 10, pages 578-587.

^{Nasp (α OF n Nonyl) -} β OBzl 3.00g and palladium - activated carbon (PD10%) (hereinafter, referred to as Pd / C) 2.29 g (manufactured by Wako Pure Chemical Co.) was added to methanol 33ml This solution was stirred at 25 ° C. for 3 and a half hours in a hydrogen atmosphere. The solvent was distilled off under reduced pressure, and N-aspartic acid ^α 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluoro- 4.88 g of a mixture of 1-nonyl ester (hereinafter referred to as Nasp ( ^α OF ⁿ Nonyl) -OH) and Pd / C was obtained. This synthesis method was based on the method described in Journal of peptide science, 2004, No. 10, pages 578-587.

620 mg of a mixture of Nasp ( ^α OF ⁿ Nonyl) -OH) and Pd / C, 92 mg of benzaldehyde (manufactured by Wako Pure Chemical Industries, Ltd.), 501 mg of fullerene [C60] (manufactured by Wako Pure Chemical Industries, Ltd.) into 200 ml of toluene. After dissolution, the solution was stirred at 120 ° C. for 16 hours. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; toluene: hexane = 1: 7) to obtain 180 mg of phenylfulleropyrrolidine derivative FnNcmPFP. This synthesis method was based on the method described in Journal of Organic Chemistry, 2001, 66, pages 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100.

(Production Example 6)
As a fulleropyrrolidine derivative, N- (n-butyroxycarbonyl) methyl-2-phenyl [60] fulleropyrrolidine (hereinafter referred to as nBcmPFP; compound represented by the general formula (35)) (F1-2), and The diadduct (hereinafter referred to as Bis-nBcmPFP, a compound represented by the general formula (36)) (F1-3) was synthesized.

Synthesis of nBcmPFP (general formula (35)) and Bis-nBcmPFP (general formula (36)) 2.50 g of glycine (manufactured by Wako Pure Chemical Industries, Ltd.) and 7.60 g of p-toluenesulfonic acid monohydrate (sum) After dissolving the pure water (manufactured by Kojun Pharmaceutical Co., Ltd.) in a mixed solution of 46 ml of n-butyl alcohol (manufactured by Wako Pure Chemical Industries, Ltd.) and 80 ml of toluene, the Dean-Stark apparatus is used while heating the solution to 130 ° C. After stirring for 14 hours while removing generated water by an azeotropic method, toluene and n-butyl alcohol were distilled off under reduced pressure. The residue was added hexane, By filtration, glycine -n- butyl ester p- toluenesulfonic acid salt (hereinafter referred to as ^Gly-O n Bu · TSA) was obtained 7.16 g. This synthesis method was based on the method described in Tetrahedron, 1926, No. 71, pages 79-80.
^Gly-O n Bu · TSA 7.16g and N- ethyldiisopropylamine 7.67 g (Wako Pure Chemical Co.), benzyl bromoacetate 4.35g (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in tetrahydrofuran 28ml The solution was then stirred at 70 ° C. for 18 hours. 71 ml of ethyl acetate was added, and the organic layer was washed 3 times with 24 ml of 1M aqueous potassium hydrogen sulfate solution and twice with saturated brine, then anhydrous magnesium sulfate was added, and the mixture was allowed to stand at 25 ° C. for 3 hours. After anhydrous magnesium sulfate was removed by filtration and the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; ethyl acetate: hexane = 1: 1), and N-aspartic acid ^α n-butyl ester ^β benzyl ester ( ^{later, Nasp (α O n Bu)} - to obtain a ^beta OBzl called a) 4.20 g. This synthesis method was based on the method described in Journal of peptide science, 2004, No. 10, pages 578-587.

^{Nasp (α O n Bu) -} β OBzl 3.00g and palladium - activated carbon (PD10%) (hereinafter, referred to as Pd / C) 2.29 g (manufactured by Wako Pure Chemical Co.) was added to methanol 33ml This solution was stirred at 25 ° C. for 3 and a half hours in a hydrogen atmosphere. Pd / C was filtered off using Celite (No. 545) (manufactured by Wako Pure Chemical Industries, Ltd.), and then the solvent was distilled off under reduced pressure. The residue was washed with hexane, N- aspartic acid ^alpha n-butyl ester (hereinafter referred to as ^{Nasp (α O n Bu) -OH} ) was obtained 2.03 g. This synthesis method was based on the method described in Journal of peptide science, 2004, No. 10, pages 578-587.

^{Nasp (α O n Bu) -OH} 110mg benzaldehyde 92 mg (manufactured by Wako Pure Chemical Co.), after fullerene [C60] 501 mg of the (manufactured by Wako Pure Chemical Co.) was dissolved in toluene 200 ml, and this solution 120 Stir at 16 ° C. for 16 hours. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; toluene: hexane = 1: 7) to obtain 120 mg of phenylfulleropyrrolidine derivative nBcmPFP and 10 mg of its diadduct Bis-nBcmPFP. This synthesis method was based on the method described in Journal of Organic Chemistry, 2001, 66, pages 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100.

(Production Example 7)
Synthesis of McmPFP (General Formula (37)) As a fulleropyrrolidine derivative, N- (n-butyoxycarbonyl) methyl-2-phenyl [60] fulleropyrrolidine (hereinafter referred to as McmPFP, which is represented by General Formula (37)) Compound (F1-4) was synthesized.

2.5 g of glycine was dispersed in 50 ml of methanol and cooled to 5 ° C. Thionyl chloride 10g was dripped there over 20 minutes, and it heated on recirculation | reflux conditions for 5 hr after completion | finish of dripping. Unreacted substances and the like were distilled off under reduced pressure to obtain 4.5 g of a white solid. The entire amount of this white solid was put into a reaction vessel, and 30 ml of THF, 30 ml of DMF, 7.7 g of diisopropylmethylamine and 4.5 g of benzyl bromoacetate were added, and the reaction was performed for 72 hours under reflux conditions. 71 ml of ethyl acetate was added, and the organic layer was washed 3 times with 24 ml of 1M aqueous potassium hydrogen sulfate solution and twice with saturated brine, then anhydrous magnesium sulfate was added, and the mixture was allowed to stand at 25 ° C. for 3 hours. After anhydrous magnesium sulfate was removed by filtration and the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; ethyl acetate: hexane = 1: 1), and N-aspartic acid ^α n-methyl ester ^β benzyl ester ( ^{later, Nasp (α O n Me)} - to give the ^β OBzl called a) 4.20g. This synthesis method was based on the method described in Journal of peptide science, 2004, No. 10, pages 578-587.

^{Nasp (α O n Bu) -} β OBzl 2.68g and palladium - activated carbon (PD10%) (hereinafter, referred to as Pd / C) 2.29 g (manufactured by Wako Pure Chemical Co.) was added to methanol 33ml This solution was stirred at 25 ° C. for 3 and a half hours in a hydrogen atmosphere. Pd / C was filtered off using Celite (No. 545) (manufactured by Wako Pure Chemical Industries, Ltd.), and then the solvent was distilled off under reduced pressure. The residue was washed with hexane, N- aspartic acid ^alpha n-methyl ester (hereinafter referred to as ^{Nasp (α O n Me) -OH} ) was obtained 2.03 g. This synthesis method was based on the method described in Journal of peptide science, 2004, No. 10, pages 578-587.

^{Nasp (α O n Me) -OH} 98mg benzaldehyde 92 mg (manufactured by Wako Pure Chemical Co.), after fullerene [C60] 501 mg of the (manufactured by Wako Pure Chemical Co.) was dissolved in toluene 200 ml, and this solution 120 Stir at 16 ° C. for 16 hours. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (developing solvent; toluene: hexane = 1: 7) to obtain 105 mg of phenylfulleropyrrolidine derivative McmPFP. This synthesis method was based on the method described in Journal of Organic Chemistry, 2001, 66, pages 5033-5041, or Journal of the American Chemical Society, 2003, 125, 15093-15100.

(Production Example 8)
Synthesis of EcmPFP (General Formula (38)) The same procedure as in Production Example 8 was carried out except that 50 ml of ethanol was used instead of 50 ml of methanol in Production Example 7, and the phenylfullerpyrrolidine derivative N- (n-ethyloxycarbonyl) methyl was used. 97 mg of 2-phenyl [60] fulleropyrrolidine (hereinafter referred to as EcmPFP; compound represented by the general formula (38)) (F1-5) was obtained.

(Production Example 9)
Synthesis of nPcmPFP (General Formula (39)) In Production Example 6, the same procedure as in Production Example 7 was carried out except that 46 ml of n-propyl alcohol was used instead of 46 ml of n-butyl alcohol. -Propyloxycarbonyl) methyl-2-phenyl [60] fulleropyrrolidine (hereinafter referred to as nPcmPFP. Compound represented by the general formula (39)) (F1-6) (101 mg) was obtained.

(Production Example 10)
Synthesis of nOcmPFP (general formula (40)) In Production Example 6, except that 46 ml of n-octyl alcohol was used instead of 46 ml of n-butyl alcohol, the same was carried out as in Production Example 7 to obtain phenylfulleropyrrolidine derivative N- (n -Octyloxycarbonyl) methyl-2-phenyl [60] fulleropyrrolidine (hereinafter referred to as nOcmPFP; compound represented by general formula (40)) (F1-7) (95 mg) was obtained.

Example 1
(Creation of transparent electrode (Y))
As the transparent substrate and the transparent conductive film, a polyethylene terephthalate (hereinafter referred to as PET) film with an ITO film having a size of 25 mm square and a sheet resistance of 10 Ω / cm ⁻² was used. And after forming the mask of a predetermined shape on the ITO film | membrane, the ITO film | membrane was patterned by immersing this in 1N hydrochloric acid for 1 hour, and the transparent electrode was formed.

[Preparation of hole extraction layer (i-1)]
1.3% by weight of poly (styrene sulfonate) / poly (2,3-dihydrothieno [3,4-b] -1, on a PET film on which a transparent electrode made of an ITO film is formed as described above. 4-dioxin) (hereinafter referred to as “PEDOT / PSS”) (product name: BaytronP, manufactured by Bayer), spin-coated at 120 ° C. for 30 minutes to form a PEDOT / PSS film having a thickness of about 100 nm. This was designated as a hole extraction layer (i-1).

(Creation of photoelectric conversion layer (E))
Furthermore, poly-3-hexylthiophene-2,5-diyl (hereinafter referred to as P3HT) (manufactured by Wako Pure Chemical Industries, Ltd., product name 044746) / HPmaPFP [synthesized in Production Example 1] in a slightly larger range than the PEDOT / PSS film. Of the fulleropyrrolidine derivative (F3-1)] (weight ratio is 1/4) (P3HT: HPmaPFP = 15 mg: 60 mg dissolved in 5.0 mL of chlorobenzene). After spin-coating on (i-1), it dried at 25 degreeC under nitrogen stream for 1 hour, and also dried under reduced pressure at 25 degreeC for 3 hours, and formed the photoelectric converting layer (E).

(Create counter electrode)
Finally, an Al film having a thickness of 125 nm was formed as a counter electrode on the photoelectric conversion layer by vacuum deposition. The photoelectric conversion element (P-1) was manufactured as described above.

(Example 2)
A photoelectric conversion element in the same manner as in Example 1 except that the P3HT / HPmaPFP mixed solution in Example 1 was replaced with a P3HT / MeaAaPFP [fulleropyrrolidine derivative (F2-1) synthesized in Production Example 2] mixed solution. (P-2) was formed. As a specific mixed solution, a solution containing P3HT: MeeAaPFP = 15 mg: 60 mg in 5.0 mL of chlorobenzene was used.

(Example 3)
A photoelectric conversion element was obtained in the same manner as in Example 1 except that the P3HT / HPmaPFP mixed solution in Example 1 was replaced with a P3HT / BPmcPFP [fulleropyrrolidine derivative (F3-2) synthesized in Production Example 3] mixed solution. (P-3) was formed. As a specific mixed solution, a solution containing P3HT: BPmcPFP = 15 mg: 60 mg in 5.0 mL of chlorobenzene was used.

Example 4
Photoelectric conversion element (P-4) containing a plurality of fullerene derivatives as electron acceptors
Except that the P3HT / HPmaPFP mixed solution in Example 1 was replaced with a mixed solution of P3HT / HPmaPFP [fulleropyrrolidine derivative (F3-1) synthesized in Production Example 1] / PCBM (manufactured by Frontier Carbon Co., Ltd.), In the same manner as in Example 1, a photoelectric conversion element (P-4) was formed. As a specific mixed solution, a solution containing P3HT: HPmaPFP: PCBM = 15 mg: 48 mg: 12 mg in 5.0 mL of chlorobenzene was used.

(Example 5)
A photoelectric conversion element in the same manner as in Example 1 except that the P3HT / HPmaPFP mixed solution in Example 1 was replaced with a P3HT / FnNcmPFP [fulleropyrrolidine derivative (F1-1) synthesized in Production Example 5] mixed solution. (P-5) was formed. As a specific mixed solution, a solution containing P3HT: FnNcmPFP = 15 mg: 60 mg in 5.0 mL of chlorobenzene was used.

(Example 6)
Photoelectric conversion element (P-6) containing a plurality of fullerene derivatives as electron acceptors
The mixed solution of P3HT / HPmaPFP in Example 1 was converted into P3HT / FnNcmPFP [fulleropyrrolidine derivative (F1-1) synthesized in Production Example 5] / nBcmPFP [fulleropyrrolidine derivative (F1-2) synthesized in Production Example 6]. A photoelectric conversion element (P-6) was formed in the same manner as in Example 1 except that the mixed solution was replaced. As a specific mixed solution, a solution containing P3HT: FnNcmPFP: nBcmPFP = 15 mg: 48 mg: 12 mg in 5.0 mL of chlorobenzene was used.

(Example 7)
In the same manner as in Example 1, except that the P3HT / HPmaPFP mixed solution in Example 1 was replaced with the P3HT / Bis-nBcmPFP [fulleropyrrolidine derivative (F1-3) synthesized in Production Example 6] mixed solution. A conversion element (P-7) was formed. As a specific mixed solution, a solution containing P3HT: FnNcmPFP = 15 mg: 60 mg in 5.0 mL of chlorobenzene was used.

(Example 8)
(Preparation of hole extraction layer (i-1))
A hole extraction layer (i-1) was formed in the same manner as in Example 1 except that the drying condition “120 ° C., 30 minutes” was changed to “200 ° C., 10 minutes” in Example 1.

(Creation of photoelectric conversion layer (E))
In Example 1, a mixed solution of P3HT / HPmaPFP (weight ratio 1/4) was mixed with P3HT / nBcmPFP [fulleropyrrolidine derivative (F1-2) synthesized in Production Example 6] (weight ratio 1 / 0.475). Replaced with a mixed solution (P3HT: nBcmPFP = 75 mg: 35.625 mg dissolved in 5.0 mL of chlorobenzene) and dried under the condition of “drying at 25 ° C. for 1 hour under a nitrogen stream and further reducing the pressure at 25 ° C. for 3 hours. Was changed to “Dry at 140 ° C. for 9 minutes under a nitrogen stream” to form a photoelectric conversion layer (E) in the same manner as in Example 1.

(Creation of electron extraction layer (i-2))
Furthermore, after spin-coating what melt | dissolved 10 microliters of titanium tetraisopropoxide (made by Wako Pure Chemical Industries, Ltd.) in 3 mL of ethanol as an electronic taking-out layer (i-2) on the photoelectric converting layer (E), Was allowed to stand for 30 minutes to cause hydrolysis to form a titanium dioxide (TiO _x ) layer.

(Create counter electrode)
A counter electrode was produced on the electron extraction layer (i-2) in the same manner as in Example 1 to form a photoelectric conversion element (P-8).

Example 9
A photoelectric conversion element was obtained in the same manner as in Example 8, except that the P3HT / nBcmPFP mixed solution in Example 8 was replaced with the P3HT / McmPFP [fulleropyrrolidine derivative (F1-4) synthesized in Production Example 7] mixed solution. (P-9) was formed. As a specific mixed solution, a solution containing P3HT: McmPFP = 75 mg: 37.5 mg in 5.0 mL of chlorobenzene was used.

(Example 10)
A photoelectric conversion element was obtained in the same manner as in Example 8, except that the P3HT / nBcmPFP mixed solution in Example 8 was replaced with a P3HT / EcmPFP [fulleropyrrolidine derivative (F1-5) synthesized in Production Example 8] mixed solution. (P-10) was formed. As a specific mixed solution, a solution containing P3HT: EcmPFP = 75 mg: 37.5 mg in 5.0 mL of chlorobenzene was used.

(Example 11)
A photoelectric conversion element in the same manner as in Example 8, except that the P3HT / nBcmPFP mixed solution in Example 8 was replaced with a P3HT / nPcmPFP [fulleropyrrolidine derivative (F1-6) synthesized in Production Example 9] mixed solution. (P-11) was formed. As a specific mixed solution, a solution containing P3HT: EcmPFP = 75 mg: 37.5 mg in 5.0 mL of chlorobenzene was used.

(Example 12)
A photoelectric conversion element in the same manner as in Example 8, except that the P3HT / nBcmPFP mixed solution in Example 8 was replaced with a P3HT / nOcmPFP [fulleropyrrolidine derivative (F1-7) synthesized in Production Example 10] mixed solution. (P-12) was formed. As a specific mixed solution, a solution containing P3HT: nOcmPFP = 75 mg: 37.5 mg in 5.0 mL of chlorobenzene was used.

(Comparative Example 1)
A photoelectric conversion element (P′-1) was formed in the same manner as in Example 1 except that the P3HT / HPmaPFP mixed solution in Example 1 was replaced with a P3HT / PCBM mixed solution. As a specific mixed solution, a solution containing P3HT: PCBM = 15 mg: 60 mg in 5.0 mL of chlorobenzene was used.

(Comparative Example 2)
A photoelectric conversion element (P′-2) was obtained in the same manner as in Example 1 except that the P3HT / HPmaPFP mixed solution in Example 1 was replaced with a P3HT / MPmPFP (fulleropyrrolidine derivative synthesized in Production Example 4) mixed solution. ) Was formed. As a specific mixed solution, a solution containing P3HT: MPmPFP = 15 mg: 60 mg in 5.0 mL of chlorobenzene was used.

(Comparative Example 3)
The mixed solution of P3HT / nBcmPFP in Example 8 was mixed with P3HT / PCBM (weight ratio 1 / 0.5) (P3HT: PCBM = 75 mg: 37.5 mg dissolved in 5.0 mL of chlorobenzene). In the same manner as in Example 9, except that the drying condition “drying at 140 ° C. for 9 minutes under a nitrogen stream” was changed to “drying at 150 ° C. for 6 minutes under a nitrogen stream”. -3) was formed.

The photoelectric conversion elements of Examples 1 to 7 and Comparative Examples 1 and 2 were evaluated by the following methods, and the measurement results are shown in Table 1.
(Evaluation method of photoelectric conversion element)
The photoelectric conversion element was measured by irradiating the photoelectric conversion element with simulated light (air passage amount AM1.5G, incident energy 100 mW / cm ² ) of a solar simulator (manufactured by Kansai Scientific Machinery Co., Ltd .: XES-502S). Irradiation conditions: Temperature 25 ° C

Using a KEITHLEY MODEL 2400 source meter, an I (current) -V (voltage) curve was measured, and I _sc (short circuit current), V _oc (open voltage), I _MAX (current at the maximum output point), V _MAX ( Voltage at the maximum output point).
Generally, the photoelectric conversion efficiency of a photoelectric conversion element is represented by the following formula.
Photoelectric conversion efficiency η = J _sc (short circuit current density) × V _oc (open circuit voltage) × ff (form factor) / incident energy Here, J _sc (short circuit current density) and ff (form factor) are obtained by the following equations. It was.
Form factor ff = (I _MAX × V _MAX ) / (I _sc × V _oc )
Short-circuit current density J _sc = I _sc / S (effective light receiving area)
However, S = 2.5 cm × 2.5 cm = 6.25 cm ²

<Solubility in toluene>
The fulleropyrrolidine derivative (F) was added to 100 g of toluene at 25 ° C. for saturation, and the mass x (unit: g) of the saturated solution was measured. The solubility S (unit: wt%) in toluene is represented by the following formula.
Solubility in toluene S = 100 × (x−100) / x (%)

  In Examples 8 to 12 and Comparative Example 3, different types of photoelectric conversion elements with an electron extraction layer (i-2) added to Examples 1 to 7 and Comparative Examples 1 to 2 were evaluated and evaluated. Went. The evaluation results of this type of photoelectric conversion element are shown in Table 2.

  From the above evaluation results, it was proved that the fulleropyrrolidine derivative as an electron acceptor in the present invention exhibits excellent photoelectric conversion efficiency as compared with a conventional electron acceptor. Furthermore, the fulleropyrrolidine derivative of the present invention is excellent in solubility in an organic solvent, and in the device manufacturing process, simple operation and low cost are realized.

  The present invention is not limited to use as a solar cell, a color sensor, and the like, but can be widely applied to electronic devices and electronic components that include photoelectric conversion elements.

Claims (10)

A photoelectric conversion element (P) having a photoelectric conversion layer (E) containing a conductive polymer (d) and an electron acceptor (a) between two electrodes (Y) formed on a substrate (T). The photoelectric acceptor (a) contains the fulleropyrrolidine derivative (F1) represented by the following general formula (1) or the following general formula (2): .

[R ¹ is the following general formula (7) Group shown in R ² is a phenyl group . The fullerene moiety is a fullerene selected from the group consisting of C ₆₀ , C ₇₀ , C ₇₆ and C ₈₄ . ]

[Wherein R ⁸ is a methylene group ; R ⁹ is C1-C16 linear or branched monovalent aliphatic hydrocarbon group and aliphatic (semi) perfluorohydrocarbon group in which part or all of the hydrogen atoms are substituted with fluorine atoms Der Ru. ] The photoelectric conversion layer (E) is provided between two electrode layers formed on a substrate and at least one of which is transparent. The photoelectric conversion element (P) described in 1. The photoelectric conversion layer according to claim 1 or 2 , wherein the photoelectric conversion layer (E) forms a bulk heterojunction by removing the solvent from the mixed solution of the conductive polymer (d) and the electron acceptor (a). Conversion element (P). The photoelectric conversion element (P) according to any one of claims 1 to 3 , wherein the conductive polymer (d) functions as a hole acceptor (s). In general formula (1) or general formula (2), R ¹ is a general formula (7), wherein R ⁸ is a methylene group, R ⁹ is an n-butyl group, that is, an acetic acid butyl ester group, Fullerene site is _{C 60,} the photoelectric conversion device according to any one of claims 1 ~ 4 (P). The photoelectric conversion element (P) according to any one of claims 1 to 5, further comprising a charge extraction layer (i) for the purpose of promoting charge movement inside the photoelectric conversion element. The photoelectric conversion element (P) according to any one of claims 1 to 6 , wherein the electron acceptor (A) further contains a fullerene derivative other than the fulleropyrrolidine derivative (F). The photoelectric conversion device according to any one of claims 1 to 7, which is a solar cell element (S) (P). The photoelectric conversion element (P) according to claim 8 , wherein the solar cell element (S) is a tandem solar cell element (S1). The photoelectric conversion element (P) according to any one of claims 1 to 7 , wherein the photoelectric conversion element (P) is an optical sensor element (U).

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