JP2012053983A - Photoelectric converter and photoelectrochemical cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoelectric converter and a photoelectrochemical cell which achieve a high conversion efficiency and excellent durability.SOLUTION: A photoelectric converter 10 comprises a conductive support member 1, a photoreceptor layer 2 including a porous semiconductor layer containing a coloring matter, a charge mobile body layer, and a counter electrode 4. The photoreceptor layer 2 includes a multilayer structure and the porous semiconductor layer is intensified by at least one coloring matter represented as the following general formula and a haze ratio of the porous semiconductor layer at a visible light wavelength is 60% and over. Mz(LL)(LL)(X)×CI (where M represents a metal atom, LLrepresents trans-bidentatable or trans-tridentatable specific ligand coordinates to a metal atom by a nitrogen atom, LLrepresents another trans-bidentatable or trans-tridentatable ligand coordinates by a nitrogen atom, X represents monodentate or bidentate ligand coordinates by a specific group, m1 represents integers 0-3 and m2 represents integers 0-2 but either one of m1 or m2 represents integers equal to or larger than 1, m3 represents integers 0-2 and CI represents a counter ion for electrical charge neutralization).

Description

  The present invention relates to a photoelectric conversion element and a photoelectrochemical cell having high conversion efficiency and excellent durability.

  Photoelectric conversion elements are used in various optical sensors, copying machines, photoelectrochemical cells (for example, solar cells), and the like. Various types of photoelectric conversion elements have been put to practical use, such as those using metals, semiconductors, organic pigments and dyes, or combinations thereof. Above all, a solar cell using non-depleting solar energy does not require fuel, and its full-scale practical use is expected greatly as it uses inexhaustible clean energy. Among these, silicon solar cells have been researched and developed for a long time. It is spreading due to the policy considerations of each country. However, silicon is an inorganic material, and its throughput and molecular modification are naturally limited.

  Therefore, research on dye-sensitized solar cells has been vigorously conducted. In particular, Graetzel et al. Of Lausanne University of Technology in Switzerland developed a dye-sensitized solar cell in which a dye composed of a ruthenium complex was fixed on the surface of a porous titanium oxide thin film, and realized conversion efficiency comparable to amorphous silicon. As a result, dye-sensitized solar cells have attracted a great deal of attention from researchers around the world.

  Patent Document 1 describes a dye-sensitized photoelectric conversion element using semiconductor fine particles sensitized with a ruthenium complex dye by applying this technique. In addition, a photoelectric conversion element using an inexpensive organic dye as a sensitizer has been reported. However, it is not sufficient to obtain a photoelectric conversion element with high conversion efficiency.

  In view of this, a technique has been proposed for improving the photoelectric conversion efficiency by making the photosensitive layer into a multilayer structure and setting the haze ratio at a wavelength in the visible light region of the photosensitive layer to a specific value or more (for example, Patent Documents). 2).

  By the way, the photoelectric conversion element is required to have high initial conversion efficiency, low decrease in conversion efficiency even after use, and excellent durability. However, in terms of durability, the photoelectric conversion element described in Patent Document 2 is not sufficient.

US Pat. No. 5,463,057 JP 2003-217688 A

  An object of the present invention is to provide a photoelectric conversion element and a photoelectrochemical cell having high conversion efficiency and excellent durability.

  As a result of intensive studies, the present inventors have made the photoreceptor layer a multi-layered structure, and increased the use of incident light by setting the haze ratio of the photoreceptor layer containing a dye having a specific structure to a specific value or more. It has been found that a photoelectric conversion element and a photoelectrochemical cell that can greatly improve the rate, have high conversion efficiency, and excellent durability can be provided. The present invention has been made based on this finding.

  The object of the present invention has been achieved by the following means.

<1> A photoelectric conversion element comprising a conductive support, a photosensitive layer composed of a porous semiconductor layer containing a dye, a charge transfer layer, and a counter electrode,
The photoreceptor layer has a multilayer structure, the porous semiconductor layer contains at least one dye represented by the following general formula (1), and the haze ratio at a wavelength in the visible light region of the porous semiconductor layer is A photoelectric conversion element characterized by being 60% or more.

Mz (LL ¹ ) _m1 (LL ² ) _m2 (X) _m3 · CI (1)
[Mz represents a metal atom, LL ¹ is a bidentate or tridentate ligand represented by the following general formula (2), and LL ² has a substituent represented by the following general formula (3). It may be a bidentate or tridentate ligand.

m1 represents an integer of 0 to 3, and when m1 is 2 or more, LL1 may be the same or different. m2 represents an integer of 0 to 2, LL ² when m2 is 2 may be the same or different. However, one of m1 and m2 is an integer of 1 or more. m3 represents an integer of 0 to 3.

  X represents a ligand, an acyloxy group, an acylthio group, a thioacyloxy group, a thioacylthio group, an acylaminooxy group, a thiocarbamate group, a dithiocarbamate group, a thiocarbonate group, a dithiocarbonate group, a trithiocarbonate group, A monodentate or bidentate arrangement coordinated by a group selected from the group consisting of an acyl group, a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group, an alkylthio group, an arylthio group, an alkoxy group, and an aryloxy group. A ligand or a monodentate or bidentate ligand composed of a halogen atom, carbonyl, dialkyl ketone, 1,3-diketone, carbonamide, thiocarbonamide or thiourea. ]

［ 一般式（２）において、Ｒ^１０１及びＲ^１０２はそれぞれ独立に、カルボキシル基、スルホン酸基、ヒドロキシル基、ヒドロキサム酸基、ホスホリル基又はホスホニル基を表す。Ｒ^１０３及びＲ^１０４はそれぞれ独立に置換基を表し、Ｒ^１０５及びＲ^１０６はそれぞれ独立にアルキル基、アリール基及びヘテロ環基のうちの一つ以上の基を表す。

[In General Formula (2), R ¹⁰¹ and R ¹⁰² each independently represent a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group, or a phosphonyl group. R ¹⁰³ and R ¹⁰⁴ each independently represent a substituent, and R ¹⁰⁵ and R ¹⁰⁶ each independently represent one or more groups of an alkyl group, an aryl group, and a heterocyclic group.

L ¹ and L ² each independently represents a conjugated chain composed of an ethenylene group and / or an ethynylene group.

a1 and a2 each independently represent an integer of 0 to 3, R ¹⁰¹ may be the same or different when a1 is 2 or more, and R ¹⁰² may be the same or different when a2 is 2 or more, b1 And b2 each independently represents an integer of 0 to 3. When b1 is 2 or more, R ³ may be the same or different, R ³ may be connected to each other to form a ring, and when b2 is 2 or more, R 4 may be the same or different and are connected to each other. may form a ring Te may be 1 or more when b1 and b2 are both linked and the ^{R 103} and ^{R 104} form a ring, d1 and d2 each independently represent an integer of 0 to 5 , D3 represents 0 or 1. ]

［ 一般式（３）において、Ｚａ、Ｚｂ及びＺｃはそれぞれ独立に、５又は６員環を形成しうる非金属原子群を表し、ｃは０又は１を表す。］
＜２＞ 前記一般式（１）中のＭがＲｕ、Ｆｅ、Ｏｓ又はＣｕであることを特徴とする＜１＞に記載の光電変換素子。
＜３＞ 前記一般式（１）中のＭがＲｕであることを特徴とすることを特徴とする＜２＞に記載の光電変換素子。
＜４＞ 前記一般式（１）中のＬＬ^１が下記一般式（４−１）、（４−２）又は（４−３）により表される２座又は３座の配位子であることを特徴とする＜１＞〜＜３＞のいずれか１項に記載の光電変換素子。

[In General Formula (3), Za, Zb, and Zc each independently represent a nonmetallic atom group that can form a 5- or 6-membered ring, and c represents 0 or 1. ]
<2> The photoelectric conversion element according to <1>, wherein M in the general formula (1) is Ru, Fe, Os, or Cu.
<3> The photoelectric conversion element according to <2>, wherein M in the general formula (1) is Ru.
<4> LL ¹ in the general formula (1) is a bidentate or tridentate ligand represented by the following general formula (4-1), (4-2), or (4-3). <1>-<3> characterized by these. The photoelectric conversion element of any one of <1>.

［ Ｒ^１０１、Ｒ^１０２及びＲ^１０７はそれぞれ独立にカルボキシル基、スルホン酸基、ヒドロキシル基、ヒドロキサム酸基、ホスホリル基又はホスホニル基を表す。Ｒ^１０３、Ｒ^１０４、Ｒ^１０８、Ｒ^１２５、Ｒ^１２６、Ｒ^１２７及びＲ^１２８はそれぞれ独立に置換基を表す。Ｒ^１２１〜Ｒ^１２４はそれぞれ独立に水素、アルキル基、アルケニル基又はアリール基を表す。Ｒ^１２１とＲ^１２２並びにＲ^１２３とＲ^１２４はそれぞれ互いに連結して環を形成してもよい。ａ１、ａ２及びａ３はそれぞれ独立に０〜３の整数を表す。ａ１が２以上のときＲ^１０１は同じでも異なっていてもよい。ａ２が２以上のときＲ^１０２は同じでも異なっていてもよい。ａ３が２以上のときＲ^１０７は同じでも異なっていてもよい。ｂ１及びｂ２はそれぞれ独立に０〜３の整数を表す。ｂ１が２以上のときＲ^１０３は同じでも異なっていてもよく、互いに連結して環を形成してもよい。ｂ２が２以上のときＲ^１０４は同じでも異なっていてもよく、互いに連結して環を形成してもよい。ｂ３は０〜５の整数を表し、ｂ３が２以上のときＲ^１０８は同じでも異なっていてもよく、互いに連結して環を形成してもよい。

[R ¹⁰¹ , R ¹⁰² and R ¹⁰⁷ each independently represent a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group or a phosphonyl group. R ¹⁰³ , R ¹⁰⁴ , R ¹⁰⁸ , R ¹²⁵ , R ¹²⁶ , R ¹²⁷ and R ¹²⁸ each independently represent a substituent. R ^{121 to} R ¹²⁴ each independently represent hydrogen, an alkyl group, an alkenyl group, or an aryl group. R ¹²¹ and R ^{122 and} R ¹²³ and R ¹²⁴ may be connected to each other to form a ring. a1, a2 and a3 each independently represents an integer of 0 to 3; When a1 is 2 or more, R ¹⁰¹ may be the same or different. a2 is ^{R 102} when 2 or more may be the same or different. a3 is the ^{R 107} when two or more may be the same or different. b1 and b2 each independently represents an integer of 0 to 3. When b1 is 2 or more, R ¹⁰³ may be the same or different, and may be linked to each other to form a ring. When b2 is 2 or more, R ¹⁰⁴ may be the same or different and may be connected to each other to form a ring. b3 represents an integer of 0 to 5, and when b3 is 2 or more, R ¹⁰⁸ may be the same or different, and may be connected to each other to form a ring.

When b1 and b2 in the general formula (4-1) are both 1 or more, R ¹⁰³ and R ¹⁰⁴ may be linked to form a ring. When b1 and b3 in the general formula (4-2) are both 1 or more, R ¹⁰³ and R ¹⁰⁸ may be linked to form a ring. d1 and d2 each independently represents an integer of 0 to 4. When d1 is 1 or more, R ¹²⁵ may be linked to one or both of R ¹²¹ and R ¹²² to form a ring, and when d1 is 2 or more, R ¹²⁵ may be the same or different, and They may be linked to form a ring. When d2 is 1 or more, R ¹²⁶ may be linked to one or both of R ¹²³ and R ¹²⁴ to form a ring, and when d2 is 2 or more, R ¹²⁶ may be the same or different, and They may be linked to form a ring. d3 represents 0 or 1. ]
<5> Either one or both of R ¹²¹ and R ^{122 in} the general formulas (4-1) and (4-2) are alkyl groups substituted with an alkoxy group. The photoelectric conversion element of any one of <4>.
<6> LL ² in the general formula (1) is a bidentate or tridentate ligand represented by any one of the following general formulas (5-1) to (5-8): The photoelectric conversion element according to any one of <1> to <5>.

［ Ｒ^１５１〜Ｒ^１５８はそれぞれ独立にカルボキシル基、スルホン酸基、ヒドロキシル基、ヒドロキサム酸基、ホスホリル基又はホスホニル基を表し、Ｒ^１５９〜Ｒ^１６５はそれぞれ独立に置換基を表し、Ｒ^１５１〜Ｒ^１６６は環上のどの位置に結合していてもよく、Ｒ^１６７〜Ｒ^１７１はそれぞれ独立に水素、アルキル基、アルケニル基又はアリール基を表す。ｅ１〜ｅ８、ｅ１３、ｅ１４及びｅ１６はそれぞれ独立に０〜４の整数を表し、ｅ９〜ｅ１２及びｅ１５はそれぞれ独立に０〜６の整数を表し、ｅ１〜ｅ８が２以上のとき、Ｒ^１５１〜Ｒ^１５８はそれぞれ同じでも異なっていてもよく、ｅ９〜ｅ１６が２以上のとき、Ｒ^１５９〜Ｒ^１６６はそれぞれ同じでも異なっていてもよく互いに連結して環を形成してもよい。］
＜７＞ 前記一般式（１）中のｍ１が１であり、ｍ２が１であり、ｍ３が１又は２であり、ＬＬ^２が前記一般式（５−１）により表される２座又は３座の配位子であることを特徴とする＜１＞〜＜６＞のいずれか１項に記載の光電変換素子。
＜８＞ 前記金属錯体色素がカルボキシル基、スルホン酸基、ヒドロキシル基、ヒドロキサム酸基、ホスホリル基及びホスホニル基からなる群から選ばれた少なくとも１種を有することを特徴とする＜１＞〜＜７＞のいずれか１項に記載の光電変換素子。
＜９＞ 前記感光体を構成する半導体微粒子が酸化チタン微粒子であることを特徴とする＜１＞〜＜８＞のいずれか１項に記載の光電変換素子。
＜１０＞ 前記多層構造の感光体層の各層を形成する半導体微粒子が異なる平均粒径を有していることを特徴とする＜１＞〜＜９＞のいずれか１項に記載の光電変換素子。
＜１１＞ 前記多層構造の感光体層の受光面側の半導体微粒子層の平均粒径を該半導体微粒子層の平均粒径よりも小さくすることを特徴とする＜１＞〜＜１０＞のいずれか１項に記載の光電変換素子。
＜１２＞ 前記多層構造の感光体層の多孔質半導体層の受光面側に位置する多孔質半導体層が、粒度分布の変動係数が１０以下の半導体微粒子によって形成されていることを特徴とする＜１＞〜＜１１＞のいずれか１項に記載の光電変換素子。
＜１３＞ 前記多層構造の感光体層の多孔質半導体層が、吸収スペクトルにおける最大感度波長領域を短波長側に有する層から吸収スペクトルにおける最大感度波長領域を長波長側に有する層の順で受光面側から配置されていることを特徴とする＜１＞〜＜１２＞のいずれか１項に記載の光電変換素子。
＜１４＞ ＜１＞〜＜１３＞のいずれか１項に記載の光電変換素子を備えることを特徴とする光電気化学電池。

[R ^{151 to} R ¹⁵⁸ each independently represent a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group or a phosphonyl group, R ^{159 to} R ¹⁶⁵ each independently represent a substituent, and R ¹⁵¹ to R ^{158 166} may be bonded to any position on the ring, and R ^{167 to} R ¹⁷¹ each independently represent hydrogen, an alkyl group, an alkenyl group, or an aryl group. e1 to e8, e13, e14 and e16 each independently represents an integer of 0 to 4, e9 to e12 and e15 each independently represents an integer of 0 to 6, and when e1 to e8 is 2 or more, R ¹⁵¹ to R ¹⁵⁸ may be the same as or different from each other. When e9 to e16 are 2 or more, R ^{159 to} R ¹⁶⁶ may be the same or different from each other and may be linked to each other to form a ring. ]
<7> is m1 is 1 in the general formula (1), m2 is 1, m3 is 1 or 2, LL ² is the formula (5-1) by bidentate or 3 represented The photoelectric conversion element according to any one of <1> to <6>, wherein the photoelectric conversion element is a ligand of a locus.
<8> The metal complex dye has at least one selected from the group consisting of a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group, and a phosphonyl group. <1> to <7 > The photoelectric conversion element of any one of.
<9> The photoelectric conversion element according to any one of <1> to <8>, wherein the semiconductor fine particles constituting the photoconductor are titanium oxide fine particles.
<10> The photoelectric conversion element according to any one of <1> to <9>, wherein the semiconductor fine particles forming each layer of the multi-layered photosensitive layer have different average particle diameters .
<11> Any one of <1> to <10>, wherein an average particle diameter of the semiconductor fine particle layer on the light-receiving surface side of the photosensitive layer having the multilayer structure is made smaller than an average particle diameter of the semiconductor fine particle layer. Item 1. The photoelectric conversion element according to item 1.
<12> The porous semiconductor layer positioned on the light-receiving surface side of the porous semiconductor layer of the multi-layered photosensitive layer is formed of semiconductor fine particles having a variation coefficient of particle size distribution of 10 or less < The photoelectric conversion element according to any one of 1> to <11>.
<13> The porous semiconductor layer of the multilayered photosensitive layer receives light in the order of a layer having the maximum sensitivity wavelength region in the absorption spectrum on the short wavelength side to a layer having the maximum sensitivity wavelength region in the absorption spectrum on the long wavelength side. It is arrange | positioned from the surface side, The photoelectric conversion element of any one of <1>-<12> characterized by the above-mentioned.
<14> A photoelectrochemical cell comprising the photoelectric conversion element according to any one of <1> to <13>.

  According to the present invention, it is possible to provide a photoelectric conversion element and a photoelectrochemical cell having high conversion efficiency and excellent durability.

It is sectional drawing shown typically about one embodiment of the photoelectric conversion element manufactured by this invention.

  As a result of intensive studies, the present inventors have made the photoelectric conversion with high conversion efficiency and excellent durability by setting the haze ratio of the photosensitive layer containing a dye having a specific structure to a specific value or more. It discovered that it could be set as an element and a photoelectrochemical cell. The present invention has been made based on this finding.

  A preferred embodiment of the photoelectric conversion element of the present invention will be described with reference to the schematic cross-sectional view of FIG.

  As shown in FIG. 1, the photoelectric conversion element 10 includes a conductive support 1, a photosensitive layer 2, a charge transfer layer 3, and a counter electrode 4 arranged in that order on the conductive support 1. The conductive support 1 and the photoreceptor layer 2 constitute a light receiving electrode 5. The photoreceptor layer 2 has semiconductor fine particles 22 and a sensitizing dye (hereinafter also simply referred to as a dye) 21. At least a part of the sensitizing dye 21 is adsorbed on the semiconductor fine particles 22 (the sensitizing dye 21 is in an adsorption equilibrium state and may be partially present in the charge transfer layer 3). The charge transfer body layer 3 functions as, for example, a hole transport layer that transports holes. The conductive support 1 on which the photoreceptor layer 2 is formed functions as a working electrode in the photoelectric conversion element 10. The photoelectric conversion element 10 can be operated as the photoelectrochemical cell 100 by causing the external circuit 6 to work.

  The light receiving electrode 5 is an electrode composed of a conductive support 1 and a photosensitive layer 2 (semiconductor film) of semiconductor fine particles 22 adsorbed by a sensitizing dye 21 coated on the conductive support 1. Light incident on the photoreceptor layer 2 (semiconductor film) excites the dye. The excited dye has high energy electrons. Therefore, the electrons are transferred from the sensitizing dye 21 to the conduction band of the semiconductor fine particles 22 and reach the conductive support 1 by diffusion. At this time, the molecule of the sensitizing dye 21 is an oxidant. The electrons on the electrode return to the oxidant while working in the external circuit 6, thereby acting as the photoelectrochemical cell 100. At this time, the light receiving electrode 5 functions as a negative electrode of the battery.

  The photoreceptor layer 2 is composed of a porous semiconductor layer composed of a layer of semiconductor fine particles 22 to which a dye described later is adsorbed. This dye may be partially dissociated in the electrolyte. The photoreceptor layer 2 is designed according to the purpose and has a multilayer structure.

  As described above, since the photosensitive layer 2 includes the semiconductor fine particles 22 on which a specific dye is adsorbed, the light receiving sensitivity is high, and when used as the photoelectrochemical cell 100, high photoelectric conversion efficiency can be obtained. Furthermore, it has high durability.

(A) Dye In the photoreceptor layer 2, the porous semiconductor layer is sensitized with at least one dye 21 represented by the following general formula (1). In the general formula (1), Mz represents a metal atom.
Mz (LL ¹ ) _m1 (LL ² ) _m2 (X) _m3 · CI (1)

(A1) Metal atom Mz
Mz represents a metal atom. Mz is preferably a metal capable of tetracoordinate or hexacoordinate, and more preferably Ru, Fe, Os, Cu, W, Cr, Mo, Ni, Pd, Pt, Co, Ir, Rh, Re, Mn Or it is Zn. Particularly preferred is Ru, Os, Zn or Cu, and most preferred is Ru.

(A2) Ligand LL ¹
The ligand LL ¹ is a bidentate or tridentate ligand represented by the following general formula (2), preferably a bidentate ligand. M1 representing the number of the ligand LL ¹ is an integer of 0 to 3, preferably 1 to 3, and more preferably 1. When m1 is 2 or more, ligands LL ¹ may be the same or different. However, the m1, at least one of m2 representing the number of ligands LL ² below is an integer of 1 or more. Accordingly, either one or both of the ligand LL ¹ and the ligand LL ² are coordinated to the metal atom.

R ¹⁰¹ and R ¹⁰² in the general formula (2) each independently represent an acidic group, for example, a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group (preferably a hydroxamic acid group having 1 to 20 carbon atoms, for example, , —CONHOH, —CONCH ₃ OH, etc.), phosphoryl groups (eg —OP (O) (OH) ₂ etc.) and phosphonyl groups (eg —P (O) (OH) ₂ etc.), preferably carboxyl groups A phosphonyl group, more preferably a carboxyl group. R ¹⁰¹ and R ¹⁰² may be substituted on any carbon atom on the pyridine ring.

In the general formula (2), R ¹⁰³ and R ¹⁰⁴ each independently represent a substituent, preferably an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, such as methyl, ethyl, isopropyl, t-butyl, pentyl. , Heptyl, 1-ethylpentyl, benzyl, 2-ethoxyethyl, 1-carboxymethyl, etc.), an alkenyl group (preferably an alkenyl group having 2 to 20 carbon atoms, such as vinyl, allyl, oleyl, etc.), an alkynyl group ( Preferably an alkynyl group having 2 to 20 carbon atoms such as ethynyl, butadiynyl, phenylethynyl and the like, a cycloalkyl group (preferably a cycloalkyl group having 3 to 20 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, 4 -Methylcyclohexyl, etc.), aryl groups (preferably the number of carbon atoms To 26 aryl groups such as phenyl, 1-naphthyl, 4-methoxyphenyl, 2-chlorophenyl, 3-methylphenyl, etc., heterocyclic groups (preferably having 2 to 20 carbon atoms, such as 2 -Pyridyl, 4-pyridyl, 2-imidazolyl, 2-benzimidazolyl, 2-thiazolyl, 2-oxazolyl, etc.), an alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms such as methoxy, ethoxy, isopropyloxy, benzyl Oxy, etc.), aryloxy groups (preferably aryloxy groups having 6 to 26 carbon atoms, such as phenoxy, 1-naphthyloxy, 3-methylphenoxy, 4-methoxyphenoxy, etc.), alkoxycarbonyl groups (preferably carbon atoms) A number 2 to 20 alkoxycarbonyl group such as ethoxy Rubonyl, 2-ethylhexyloxycarbonyl, etc.), amino group (preferably an amino group having 0-20 carbon atoms, such as amino, N, N-dimethylamino, N, N-diethylamino, N-ethylamino, anilino, etc.) A sulfonamide group (preferably a sulfonamide group having 0 to 20 carbon atoms, such as N, N-dimethylsulfonamide, N-phenylsulfonamide, etc.), an acyloxy group (preferably an acyloxy group having 1 to 20 carbon atoms) For example, acetyloxy, benzoyloxy, etc.), carbamoyl groups (preferably carbamoyl groups having 1 to 20 carbon atoms, such as N, N-dimethylcarbamoyl, N-phenylcarbamoyl etc.), acylamino groups (preferably carbon atoms) 1-20 acylamino groups such as acetylamino, benzoy A cyano group, a cyano group, or a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), more preferably an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group. , Alkoxycarbonyl group, amino group, acylamino group, cyano group or halogen atom, particularly preferably alkyl group, alkenyl group, heterocyclic group, alkoxy group, alkoxycarbonyl group, amino group, acylamino group or cyano group.

When the ligand LL ¹ contains an alkyl group, an alkenyl group or the like, these may be linear or branched, and may be substituted or unsubstituted. Further, when the ligand LL ¹ contains an aryl group, a heterocyclic group or the like, they may be monocyclic or condensed and may be substituted or unsubstituted.

In General Formula (2), R ¹⁰⁵ and R ¹⁰⁶ are each independently an aromatic group (preferably an aromatic group having 6 to 30 carbon atoms, such as phenyl, substituted phenyl, naphthyl, substituted naphthyl, etc.), or hetero A cyclic group (preferably a heterocyclic group having 1 to 30 carbon atoms, such as 2-thienyl, 2-pyrrolyl, 2-imidazolyl, 1-imidazolyl, 4-pyridyl, 3-indolyl), preferably 1 to 3 A heterocyclic group having one electron donating group, more preferably thienyl. The electron donating group is an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an amino group, an acylamino group (preferred examples are the same as those for R ¹⁰¹ and R ¹⁰² ) or a hydroxyl group. And more preferably an alkyl group, an alkoxy group, an amino group or a hydroxyl group, and particularly preferably an alkyl group. R ¹⁰³ and R ¹⁰⁴ may be the same or different, but are preferably the same.

R ¹⁰⁵ and R ¹⁰⁶ may be directly bonded to the benzene ring. R ¹⁰⁵ and R ¹⁰⁶ may be bonded to the benzene ring via one or both of L ¹ and L ² .

Here, L ¹ and L ² each independently represent a conjugated chain composed of an ethenylene group and / or an ethynylene group. When the ethenylene group has a substituent, the substituent is preferably an alkyl group, and more preferably methyl. L ¹ and L ² are each independently preferably a conjugated chain having 2 to 6 carbon atoms, more preferably ethenylene, butadienylene, ethynylene, butadienylene, methylethenylene or dimethylethenylene, particularly ethenylene or butadienylene. Preferably, ethenylene is most preferred. L ¹ and L ² may be the same or different, but are preferably the same. When the conjugated chain contains a carbon-carbon double bond, each double bond may be a trans isomer, a cis isomer, or a mixture thereof.

d3 is 0 or 1, and a1 and a2 each independently represent an integer of 0 to 3. a1 is R ¹⁰¹ when 2 or more may be the same or different, a2 is 2 or more when R ¹⁰² may be the same or different. a1 is preferably 0 or 1, and a2 is preferably an integer of 0 to 2. In particular, when d3 is 0, a2 is preferably 1 or 2, and when d3 is 1, a2 is preferably 0 or 1. The sum of a1 and a2 is preferably an integer of 0-2.

b1 and b2 each independently represent an integer of 0 to 3, preferably an integer of 0 to 2. When b1 is 2 or more, R ¹⁰³ may be the same or different and may be connected to each other to form a ring. When b2 is 2 or more, R ¹⁰⁴ may be the same or different, and may be connected to each other to form a ring. When b1 and b2 are both 1 or more, R ¹⁰³ and R ¹⁰⁴ may be linked to form a ring. Preferable examples of the ring to be formed include a benzene ring, a pyridine ring, a thiophene ring, a pyrrole ring, a cyclohexane ring, a cyclopentane ring and the like.

When the sum of a1 and a2 is 1 or more and the ligand LL ¹ has at least one acidic group, m1 in the general formula (2) is preferably 2 or 3, and preferably 2. Is more preferable.
The ligand LL ¹ in the general formula (2) is preferably a case where R105 or R106 represents a phenyl group, a thienyl group, a furyl group, or a pyryl group, and contains an alkyl group having 2 or more carbon atoms as a substituent. .
More preferably as the ligand LL ¹ in the general formula (2), R105 or R106 represents a phenyl group, a thienyl group, a furyl group, a pyryl group, and contains an alkyl group having 2 or more carbon atoms as a substituent, and This is a case where both a1 and a2 are 0.
More preferably, as the ligand LL ¹ in the general formula (2), R105 or R106 represents a phenyl group, a thienyl group, and an alkyl group having 3 or more carbon atoms as a substituent, and a1, a2, b1 and This is a case where b2 is all zero.

The ligand LL ¹ in the general formula (2) is more preferably represented by the following general formula (4-1), (4-2) or (4-3).

In the general formulas (4-1) to (4-3), R ^{101 to} R ¹⁰⁴ , a1, a2, b1, b2, and d3 have the same meanings as those in the general formula (14).

In General Formula (4-2), R ¹⁰⁷ represents an acidic group, preferably a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group, or a phosphonyl group, more preferably a carboxyl group or a phosphoryl group. Yes, particularly preferably a carboxyl group.

In the general formula (4-2), R ¹⁰⁸ represents a substituent, preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an amino group or an acylamino group (above preferred examples are R ¹⁰³ and R ¹⁰⁴ in the general formula (2)), and more preferably an alkyl group, an alkoxy group, an amino group, or an acylamino group.

In general formulas (4-1) and (4-2), R ^{121 to} R ¹²⁴ each independently represents hydrogen, an alkyl group, an alkenyl group, or an aryl group. Preferred examples of R ^{121 to} R ¹²⁴ are the same as the preferred examples of R ¹⁰³ and R ¹⁰⁴ in formula (2). R ^{121 to} R ¹²⁴ are more preferably an alkyl group or an aryl group, and more preferably an alkyl group. When R ^{121 to} R ¹²⁴ are alkyl groups, they may further have a substituent, and the substituent is preferably an alkoxy group, a cyano group, an alkoxycarbonyl group or a carbonamido group, particularly preferably an alkoxy group. R ¹²¹ and R ¹²² and R ¹²³ and R ¹²⁴ may be connected to each other to form a ring. As the ring to be formed, a pyrrolidine ring, a piperidine ring, a piperazine ring, a morpholine ring or the like is preferable.

In General Formulas (4-1) to (4-3), R ¹²⁵ , R ¹²⁶ , R ¹²⁷ and R ¹²⁸ each independently represent a substituent, preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, An alkoxy group, an aryloxy group, an amino group, an acylamino group (preferred examples are the same as those for R ¹⁰¹ in the general formula (2)) or a hydroxyl group, more preferably an alkyl group, an alkenyl group, and an alkynyl group. Group, an alkoxy group, an amino group or an acylamino group, particularly preferably an alkyl group or an alkynyl group.

In general formula (4-2), a3 represents the integer of 0-3, Preferably the integer of 0-2 is represented. When d3 is 0, a3 is preferably 1 or 2, and when d3 is 1, a3 is preferably 0 or 1. a3 is the ^{R 107} when two or more may be the same or different.

In general formulas (4-1) and (4-2), d1 and d2 each independently represent an integer of 0 to 4. When d1 is 1 or more, R ¹²⁵ may be linked to one or both of R ¹²¹ and R ¹²² to form a ring. The ring formed is preferably a piperidine ring or a pyrrolidine ring. When d1 is 2 or more, R ¹²⁵ may be the same or different, and may be linked to each other to form a ring. When d2 is 1 or more, R ¹²⁶ may be linked to one or both of R ¹²³ and R ¹²⁴ to form a ring. The ring formed is preferably a piperidine ring or a pyrrolidine ring. When d2 is 2 or more, R ¹²⁶ may be the same or different, and may be linked to each other to form a ring.

(A3) Ligand LL ²
In the general formula (1), the ligand LL ² represents a bidentate or tridentate ligand. M2 representing the number of ligands LL ² is an integer of 0 to 2, and is preferably 0 or 1. m2 is the ligand LL ² when the two may be the same or different. However, the m2, at least one of which is an integer of 1 or more of the m1 representing the number of ligands LL ¹ above.

Ligand LL ² is a bidentate or tridentate ligand represented by the following general formula (3).

一般式（３）中、Ｚａ、Ｚｂ及びＺｃはそれぞれ独立に、５員環又は６員環を形成しうる非金属原子群を表す。形成される５員環又は６員環は置換されていても無置換でもよく、単環でも縮環していてもよい。

In General Formula (3), Za, Zb, and Zc each independently represent a nonmetallic atom group that can form a 5-membered ring or a 6-membered ring. The formed 5-membered or 6-membered ring may be substituted or unsubstituted, and may be monocyclic or condensed.

  Za, Zb, and Zc are each preferably a 5-membered or 6-membered ring having a carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom, or a phosphorus atom. It may have a halogen atom. Za, Zb or Zc is preferably an aromatic ring. In the case of a 5-membered ring, an imidazole ring, an oxazole ring, a thiazole ring or a triazole ring is preferably formed. In the case of a 6-membered ring, a pyridine ring, a pyrimidine ring, a pyridazine ring or a pyrazine ring is preferably formed. Of these, an imidazole ring or a pyridine ring is more preferable.

In general formula (15), c represents 0 or 1. c is preferably 0, and the ligand LL ² is preferably a bidentate ligand.

Ligand LL ² is preferably represented by any of the following general formula (5-1) to (5-8), the formula (5-1), (5-2), (5-4 ) Or (5-6), more preferably represented by formula (5-1) or (5-2), and represented by formula (5-1). Is most preferred.

なお、一般式（５−１）〜（５−８）中のＲ^１５１〜Ｒ^１６６は図示の都合上１つの環上に置換したように描写しているが、その環上にあっても、または図示されたものとは異なる環状に置換していてもよい。

In addition, although R ^{151 to} R ¹⁶⁶ in the general formulas (5-1) to (5-8) are depicted as substituted on one ring for the convenience of illustration, Alternatively, it may be substituted with a different ring from that shown.

In general formulas (5-1) to (5-8), R ^{151 to} R ¹⁵⁸ each independently represent an acidic group. R ^{151 to} R ¹⁵⁸ are, for example, a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group (preferably a hydroxamic acid group having 1 to 20 carbon atoms, such as —CONHOH, —CONCH ₃ OH, etc.), a phosphoryl group ( For example, —OP (O) (OH) ₂ etc.) or a phosphonyl group (eg —P (O) (OH) ₂ etc.) is represented. R ^{151 to} R ¹⁵⁸ are preferably a carboxyl group, a phosphoryl group, or a phosphonyl group, more preferably a carboxyl group or a phosphonyl group, and more preferably a carboxyl group.

In general formulas (5-1) to (5-8), R ^{159 to} R ¹⁶⁶ each independently represent a substituent, preferably an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, a heterocyclic group, or an alkoxy group. , An aryloxy group, an alkoxycarbonyl group, an amino group, an acyl group, a sulfonamide group, an acyloxy group, a carbamoyl group, an acylamino group, a cyano group, or a halogen atom (above preferred examples are R ¹⁰³ and R ¹⁰⁴ in the general formula (14)) More preferably an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an alkoxycarbonyl group, an amino group, an acylamino group or a halogen atom, particularly preferably an alkyl group or an alkenyl group. , Alkoxy group, alkoxycarbonyl group, amino group or acylamino group A.

In general formulas (5-1) to (5-8), R ^{167 to} R ¹⁷¹ each independently represent a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group bonded with a carbon atom. Of these, an aliphatic group and an aromatic group are preferable. More preferably, it is an aliphatic group having a carboxyl group. When the ligand LL ² contains an alkyl group, an alkenyl group or the like, they may be linear or branched and may be unsubstituted substituted. Also, when the ligand LL ² contains an aryl group, a heterocyclic group, they may be a condensed ring may be monocyclic or be unsubstituted substituted.

In general formulas (5-1) to (5-8), R ^{151 to} R ¹⁶⁶ may be bonded to any position on the ring. E1 to e6 each independently represents an integer of 0 to 4, preferably an integer of 1 to 2. e7 and e8 each independently represents an integer of 0 to 4, preferably an integer of 1 to 3. e9 to e12 and e15 each independently represents an integer of 0 to 6, and e13, e14 and e16 each independently represents an integer of 0 to 4. e9 to e16 are each independently preferably an integer of 0 to 3.

When e1 to e8 is 2 or more, R ^{151 to} R ¹⁵⁸ may be the same or different. When e9 to e16 is 2 or more, R ^{159 to} R ¹⁶⁶ may be the same or different and are connected to each other. To form a ring.

(A4) Ligand X
In the general formula (1), the ligand X represents a monodentate or bidentate ligand. M3 representing the number of ligands X represents an integer of 0 to 2, and m3 is preferably 1 or 2. When the ligand X is a monodentate ligand, m3 is preferably 2. When the ligand X is a bidentate ligand, m3 is preferably 1. When m3 is 2, the ligands X may be the same or different, and the ligands X may be linked to each other.

The ligand X is an acyloxy group (preferably an acyloxy group having 1 to 20 carbon atoms, such as acetyloxy, benzoyloxy, salicylic acid, glycyloxy, N, N-dimethylglycyloxy, oxalylene (—OC (O) C (O) O-), etc.), an acylthio group (preferably an acylthio group having 1 to 20 carbon atoms, such as acetylthio, benzoylthio, etc.), a thioacyloxy group (preferably a thioacyloxy group having 1 to 20 carbon atoms, For example, a thioacetyloxy group (CH ₃ C (S) O—) and the like)), a thioacylthio group (preferably a thioacylthio group having 1 to 20 carbon atoms, such as thioacetylthio (CH ₃ C (S) S—) , Thiobenzoylthio (PhC (S) S—) and the like)), an acylaminooxy group (preferably an aryl having 1 to 20 carbon atoms) Silaminooxy group, for example, N-methylbenzoylaminooxy (PhC (O) N (CH ₃ ) O—), acetylaminooxy (CH ₃ C (O) NHO—), etc.)), thiocarbamate group (preferably A thiocarbamate group having 1 to 20 carbon atoms, such as N, N-diethylthiocarbamate, etc., a dithiocarbamate group (preferably a dithiocarbamate group having 1 to 20 carbon atoms, such as N-phenyldithiocarbamate, N, N-dimethyldithiocarbamate, N, N-diethyldithiocarbamate, N, N-dibenzyldithiocarbamate, etc.), a thiocarbonate group (preferably a thiocarbonate group having 1 to 20 carbon atoms, such as ethylthiocarbonate) Etc.), dithiocarbonate (preferably dithiocarbonate having 1 to 20 carbon atoms) Such as ethyl dithiocarbonate (C ₂ H ₅ OC (S) S—), etc., trithiocarbonate group (preferably a trithiocarbonate group having 1 to 20 carbon atoms, such as ethyl trithiocarbonate sulphonate _{(C 2 H 5 SC (S} ) S-) and the like), an acyl group (preferably an acyl group having 1 to 20 carbon atoms, e.g., acetyl, benzoyl, etc.), a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate Group, cyano group, alkylthio group (preferably an alkylthio group having 1 to 20 carbon atoms such as methanethio, ethylenedithio, etc.), arylthio group (preferably an arylthio group having 6 to 20 carbon atoms such as benzenethio, 1, 2 -Phenylenedithio etc.), an alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms, such as metho A monodentate or bidentate coordinated with a group selected from the group consisting of an aryloxy group (preferably an aryloxy group having 6 to 20 carbon atoms, such as phenoxy, quinoline-8-hydroxyl, etc.) A ligand, or a halogen atom (preferably a chlorine atom, a bromine atom, an iodine atom, etc.), a carbonyl (... CO), a dialkyl ketone (preferably a dialkyl ketone having 3 to 20 carbon atoms, such as acetone ((CH ₃ ) ₂ ). CO ...), etc.), 1,3-diketone (preferably having 3 to 20 carbon atoms 1,3-diketones, for example, acetylacetone _{(CH 3 C (O ...)} CH = C (O-) CH 3), tri fluoro acetylacetone _{(CF 3 C (O ...)} CH = C (O-) CH 3), dipivaloylmethane _{(tC 4 H 9 C (O} ...) CH = C (O-) tC 4 H ), Dibenzoylmethane (PhC (O ...) CH = C (O-) Ph), 3- chloro-acetylacetone _{(CH 3 C (O ...)} CCl = C (O-) CH 3) , etc.), carbonamido (preferably Is a carbonamide having 1 to 20 carbon atoms, such as CH ₃ N═C (CH ₃ ) O—, —OC (═NH) —C (═NH) O—, etc.), thiocarbonamide (preferably having carbon atoms 1 to 20 thiocarbonamides, such as CH ₃ N═C (CH ₃ ) S—, or thiourea (preferably thioureas having 1 to 20 carbon atoms, such as NH (...) = C (S— ) NH ₂ , CH ₃ N (...) = C (S—) NHCH ₃ , (CH ₃ ) ₂ N—C (S...) N (CH ₃ ) _2, etc.) "..." indicates a coordination bond.

  The ligand X is preferably an acyloxy group, a thioacylthio group, an acylaminooxy group, a dithiocarbamate group, a dithiocarbonate group, a trithiocarbonate group, a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group, A ligand coordinated by a group selected from the group consisting of an alkylthio group, an arylthio group, an alkoxy group and an aryloxy group, or a ligand consisting of a halogen atom, carbonyl, 1,3-diketone or thiourea, More preferably, a ligand coordinated with a group selected from the group consisting of acyloxy group, acylaminooxy group, dithiocarbamate group, thiocyanate group, isothiocyanate group, cyanate group, isocyanate group, cyano group or arylthio group, or Halogen atom, 1,3-dike Or a thiourea ligand, particularly preferably a ligand coordinated by a group selected from the group consisting of a dithiocarbamate group, a thiocyanate group, an isothiocyanate group, a cyanate group and an isocyanate group, or a halogen atom Or a ligand consisting of a 1,3-diketone, most preferably a ligand coordinated with a group selected from the group consisting of a dithiocarbamate group, a thiocyanate group and an isothiocyanate group, or a 1,3-diketone A ligand consisting of In addition, when the ligand X contains an alkyl group, an alkenyl group, an alkynyl group, an alkylene group or the like, these may be linear or branched, and may be substituted or unsubstituted. Moreover, when an aryl group, a heterocyclic group, a cycloalkyl group, etc. are included, they may be substituted or unsubstituted, and may be monocyclic or condensed.

  When the ligand X is a bidentate ligand, the ligand X is an acyloxy group, acylthio group, thioacyloxy group, thioacylthio group, acylaminooxy group, thiocarbamate group, dithiocarbamate group, thiocarbonate group, dithio group. A ligand coordinated by a group selected from the group consisting of carbonate group, trithiocarbonate group, acyl group, alkylthio group, arylthio group, alkoxy group and aryloxy group, or 1,3-diketone, carbonamide , A thiocarbonamide, or a thiourea ligand is preferred. When the ligand X is a monodentate ligand, the ligand X is coordinated with a group selected from the group consisting of a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group, an alkylthio group, and an arylthio group. Or a ligand comprising a halogen atom, carbonyl, dialkyl ketone, or thiourea.

(A5) Counter ion CI
CI in the general formula (2) represents a counter ion when a counter ion is required to neutralize the charge. In general, whether a dye is a cation or an anion, or has a net ionic charge, depends on the metal, ligand and substituent in the dye.

  The dye of the general formula (2) may be dissociated and have a negative charge because the substituent has a dissociable group. In this case, the entire charge of the dye of the general formula (2) is electrically neutralized by the counter ion CI.

  When the counter ion CI is a positive counter ion, for example, the counter ion CI is an inorganic or organic ammonium ion (for example, tetraalkylammonium ion, pyridinium ion, etc.), an alkali metal ion, or a proton.

  When the counter ion CI is a negative counter ion, for example, the counter ion CI may be an inorganic anion or an organic anion. For example, halogen anions (eg, fluoride ions, chloride ions, bromide ions, iodide ions, etc.), substituted aryl sulfonate ions (eg, p-toluene sulfonate ions, p-chlorobenzene sulfonate ions, etc.), aryl disulfones Acid ion (for example, 1,3-benzenedisulfonic acid ion, 1,5-naphthalenedisulfonic acid ion, 2,6-naphthalenedisulfonic acid ion, etc.), alkyl sulfate ion (for example, methyl sulfate ion, etc.), sulfate ion, thiocyanate ion Perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, picrate ion, acetate ion, trifluoromethanesulfonate ion and the like. Further, as the charge balance counter ion, an ionic polymer or another dye having a charge opposite to that of the dye may be used, and a metal complex ion (for example, bisbenzene-1,2-dithiolatonickel (III)) can also be used. is there.

(A6) Bonding Group The dye having the structure represented by the general formula (1) preferably has at least one suitable bonding group (interlocking group) for the surface of the semiconductor fine particles. It is more preferable to have 1 to 6 bonding groups in the dye, and it is particularly preferable to have 1 to 4 bonding groups. Carboxyl group, sulfonic acid group, hydroxyl group, hydroxamic acid group (for example, —CONHOH), phosphoryl group (for example, —OP (O) (OH) _2, etc.), phosphonyl group (for example, —P (O) (OH) _2, etc.) It is preferable that the dye has an acidic group (substituent having a dissociable proton).

  The dye represented by the general formula (1) has a maximum absorption wavelength in the solution in the range of 500 to 700 nm, and more preferably in the range of 500 to 650 nm.

  The dye represented by the general formula (1) can be prepared by a conventional method with reference to JP-A No. 2001-291534.

  Specific examples of the dye having the structure represented by the general formula (1) used in the present invention are shown below, but the present invention is not limited thereto. In addition, when the pigment | dye in the following specific example contains the ligand which has a proton dissociable group, this ligand may dissociate as needed and may discharge | release a proton.

(B) Charge transfer body In the electrolyte composition used for the photoelectric conversion element 10 of the present invention, as an oxidation-reduction pair, for example, iodine and iodide (for example, lithium iodide, tetrabutylammonium iodide, tetrapropylammonium iodide, etc.) ), Combinations of alkyl viologens (eg methyl viologen chloride, hexyl viologen bromide, benzyl viologen tetrafluoroborate) and their reduced forms, combinations of polyhydroxybenzenes (eg hydroquinone, naphthohydroquinone, etc.) and their oxidants Examples thereof include combinations of divalent and trivalent iron complexes (for example, red blood salt and yellow blood salt). Of these, a combination of iodine and iodide is preferred.

  The cation of the iodine salt is preferably a 5-membered or 6-membered nitrogen-containing aromatic cation. In particular, when the compound represented by the general formula (1) is not an iodine salt, republished WO95 / 18456, JP-A-8-259543, Electrochemistry, Vol.65, No.11, p.923 (1997) It is preferable to use iodine salts such as pyridinium salts, imidazolium salts, and triazolium salts described in the above.

  The electrolyte composition used for the photoelectric conversion element 10 of the present invention preferably contains iodine together with the heterocyclic quaternary salt compound. The iodine content is preferably 0.1 to 20% by mass, and more preferably 0.5 to 5% by mass with respect to the entire electrolyte composition.

  The electrolyte composition used for the photoelectric conversion element 10 of the present invention may contain a solvent. The content of the solvent in the electrolyte composition is preferably 50% by mass or less, more preferably 30% by mass or less, and particularly preferably 10% by mass or less based on the entire composition.

  As the solvent, those having a low viscosity and high ion mobility, a high dielectric constant and capable of increasing the effective carrier concentration, or both are preferable because they can exhibit excellent ion conductivity. As such a solvent, carbonate compounds (ethylene carbonate, propylene carbonate, etc.), heterocyclic compounds (3-methyl-2-oxazolidinone, etc.), ether compounds (dioxane, diethyl ether, etc.), chain ethers (ethylene glycol dialkyl ether, Propylene glycol dialkyl ether, polyethylene glycol dialkyl ether, polypropylene glycol dialkyl ether, etc.), alcohols (methanol, ethanol, ethylene glycol monoalkyl ether, propylene glycol monoalkyl ether, polyethylene glycol monoalkyl ether, polypropylene glycol monoalkyl ether, etc.), Polyhydric alcohols (ethylene glycol, propylene glycol, polyethylene glycol Nitrile compounds (acetonitrile, glutarodinitrile, methoxyacetonitrile, propionitrile, benzonitrile, biscyanoethyl ether, etc.), esters (carboxylic esters, phosphate esters, phosphonates, etc.) ), Aprotic polar solvent (dimethyl sulfoxide (DMSO), sulfolane, etc.), water, hydrous electrolyte described in JP-A No. 2002-110262, JP-A No. 2000-36332, JP-A No. 2000-243134, and republication Examples include electrolyte solvents described in WO / 00-54361. These solvents may be used as a mixture of two or more.

  Further, as the electrolyte solvent, an electrochemically inert salt which is in a liquid state at room temperature and has a melting point lower than room temperature may be used. For example, 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, etc., nitrogen-containing heterocyclic quaternary salt compounds such as imidazolium salts and pyridinium salts, or tetraalkylammonium salts Is mentioned.

  The electrolyte composition used in the photoelectric conversion element of the present invention may be added with a polymer or an oil gelling agent, or may be gelled (solidified) by a technique such as polymerization of polyfunctional monomers or polymer crosslinking reaction. .

  When the electrolyte composition is gelled by adding a polymer, a compound described in Polymer Electrolyte Reviews-1 and 2 (J.R. MacCallum and CA Vincent, co-edited by ELSEVIER APPLIED SCIENCE) is added. be able to. In this case, it is preferable to use polyacrylonitrile or polyvinylidene fluoride.

  When the electrolyte composition is gelled by adding an oil gelling agent, J.I. Chem. Soc. Japan, Ind. Chem. Soc. , 46779 (1943); Am. Chem. Soc. 111, 5542 (1989); Chem. Soc. Chem. Commun. , 390 (1993), Angew. Chem. Int. Ed. Engl. , 35, 1949 (1996), Chem. Lett. , 885 (1996), J. Am. Chem. Soc. Chem. Commun. , 545, (1997) and the like, and a compound having an amide structure is preferably used.

  When gelling the electrolyte composition by polymerization of polyfunctional monomers, prepare a solution from the polyfunctional monomers, polymerization initiator, electrolyte and solvent, and use methods such as casting, coating, dipping, and impregnation. A method in which a sol-like electrolyte layer is formed on an electrode carrying a dye and then gelled by radical polymerization of a polyfunctional monomer is preferred. The polyfunctional monomers are preferably compounds having two or more ethylenically unsaturated groups, such as divinylbenzene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol Ethylene glycol dimethacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate and the like are preferable.

  The gel electrolyte may be formed by polymerization of a mixture containing a monofunctional monomer in addition to the above polyfunctional monomers. Monofunctional monomers include acrylic acid or α-alkyl acrylic acid (acrylic acid, methacrylic acid, itaconic acid, etc.) or their esters or amides or vinyl esters (vinyl acetate, etc.), maleic acid or fumaric acid or their derivatives. Esters (dimethyl maleate, dibutyl maleate, diethyl fumarate, etc.), sodium salt of p-styrenesulfonic acid, acrylonitrile, methacrylonitrile, dienes (butadiene, cyclopentadiene, isoprene, etc.), aromatic vinyl compounds (Styrene, p-chlorostyrene, t-butylstyrene, α-methylstyrene, sodium styrenesulfonate, etc.), N-vinylformamide, N-vinyl-N-methylformamide, N-vinylacetamide, N-vinyl-N- Methylacetamide, Vinyl sulfonic acid, sodium vinyl sulfonate, sodium allyl sulfonate, sodium methacryl sulfonate, vinylidene fluoride, vinylidene chloride, vinyl alkyl ethers (such as methyl vinyl ether), ethylene, propylene, butene, isobutene, N-phenylmaleimide, etc. It can be used.

  The blending amount of the polyfunctional monomer is preferably 0.5 to 70% by mass and more preferably 1.0 to 50% by mass with respect to the whole monomer. The above-mentioned monomers are the same as those described in Takayuki Otsu and Masaaki Kinoshita "Experimental Methods for Polymer Synthesis" (Chemical Doujin) and Takatsu Otsu "Lecture Polymerization Reaction Theory 1 Radical Polymerization (I)" (Chemical Doujin). Polymerization can be performed by radical polymerization which is a polymer synthesis method. The monomer for gel electrolyte used in the present invention can be radically polymerized by heating, light or electron beam, or electrochemically, and is particularly preferably radically polymerized by heating. In this case, preferably used polymerization initiators are 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), dimethyl 2,2′-azobis (2-methylpropyl). Pionate), azo initiators such as dimethyl 2,2′-azobisisobutyrate, peroxide initiators such as lauryl peroxide, benzoyl peroxide, and t-butyl peroctoate. The preferable addition amount of a polymerization initiator is 0.01-20 mass% with respect to the monomer total amount, More preferably, it is 0.1-10 mass%.

The weight composition range of the monomer in the gel electrolyte is preferably 0.5 to 70% by mass. More preferably, it is 1.0-50 mass%. When the electrolyte composition is gelled by a polymer crosslinking reaction, it is preferable to add a polymer having a reactive group capable of crosslinking to the composition and a crosslinking agent. Preferred reactive groups are nitrogen-containing heterocycles such as pyridine ring, imidazole ring, thiazole ring, oxazole ring, triazole ring, morpholine ring, piperidine ring, piperazine ring, and the preferred crosslinking agent is a functional group capable of nucleophilic attack by the nitrogen atom. Is a compound (electrophile) having two or more of, for example, a bifunctional or higher functional alkyl halide, halogenated aralkyl, sulfonic acid ester, acid anhydride, acid chloride, isocyanate and the like.

The electrolyte composition of the present invention, metal iodides (LiI, NaI, KI, CsI , CaI 2 , etc.), a metal bromide (LiBr, NaBr, KBr, CsBr , CaBr 2 , etc.), quaternary ammonium bromine salt (tetraalkylammonium Ammonium bromide, pyridinium bromide, etc.), metal complexes (ferrocyanate-ferricyanate, ferrocene-ferricinium ion, etc.), sulfur compounds (sodium polysulfide, alkylthiol-alkyldisulfides, etc.), viologen dye, hydroquinone-quinone Etc. may be added. These may be used as a mixture.

  Further, in the present invention, J.P. Am. Ceram. Soc. 80, (12), 3157-3171 (1997), and basic compounds such as 2-picoline and 2,6-lutidine may be added. A preferable concentration range in the case of adding a basic compound is 0.05 to 2M.

  Further, as the electrolyte of the present invention, a charge transport layer containing a hole conductor material may be used. As the hole conductor material, a 9,9'-spirobifluorene derivative or the like can be used.

  In addition, an electrode layer, a photoreceptor layer (photoelectric conversion layer), a charge transfer layer (hole transport layer), a conductive layer, and a counter electrode layer can be sequentially stacked. A hole transport material that functions as a p-type semiconductor can be used as the hole transport layer. As a preferred hole transport layer, for example, an inorganic or organic hole transport material can be used. Examples of the inorganic hole transport material include CuI, CuO, and NiO. Examples of the organic hole transport material include high molecular weight materials and low molecular weight materials, and examples of the high molecular weight materials include polyvinyl carbazole, polyamine, and organic polysilane. Moreover, as a low molecular weight thing, a triphenylamine derivative, a stilbene derivative, a hydrazone derivative, a phenamine derivative etc. are mentioned, for example. Among these, organic polysilanes are preferable because, unlike conventional carbon-based polymers, σ electrons delocalized along the main chain Si contribute to photoconductivity and have high hole mobility (Phys. Rev.). B, 35, 2818 (1987)).

The conductive layer is not particularly limited as long as it has good conductivity, and examples thereof include inorganic conductive materials, organic conductive materials, conductive polymers, and intermolecular charge transfer complexes. Among them, an intermolecular charge transfer complex formed from a donor material and an acceptor material is preferable. Among these, what was formed from the organic donor and the organic acceptor can be used preferably.
The thickness of this conductive layer is not particularly limited, but is preferably such that the porous layer can be completely filled.

  The donor material is preferably a material rich in electrons in the molecular structure. For example, organic donor materials include those having an amine group, hydroxyl group, ether group, selenium or sulfur atom in the π-electron system of the molecule, specifically, phenylamine-based, triphenylmethane-based, carbazole-based , Phenol-based materials, and tetrathiafulvalene-based materials. As the acceptor material, those lacking electrons in the molecular structure are preferable. For example, organic acceptor materials include fullerenes, those having a substituent such as a nitro group, a cyano group, a carboxyl group or a halogen group in the π-electron system of the molecule, specifically, PCBM, benzoquinone, naphthoquinone, etc. Quinone, fluoroenone, chloranil, bromanyl, tetracyanoquinodimethane, tetracyanoethylene and the like.

(C) Conductive Support As shown in FIG. 1, in the photoelectric conversion element of the present invention, a photosensitive layer 2 in which a sensitizing dye 21 is adsorbed on porous semiconductor fine particles 22 on a conductive support 1. Is formed. As will be described later, for example, the photoreceptor layer 2 can be produced by immersing the dispersion of semiconductor fine particles in the dye solution of the present invention after coating and drying on a conductive support.

As the conductive support 1, glass or a polymer material having a conductive film on the surface can be used as the support itself, such as metal. The conductive support 1 is preferably substantially transparent. Substantially transparent means that the light transmittance is 10% or more, preferably 50% or more, particularly preferably 80% or more. As the conductive support 1, a glass or polymer material coated with a conductive metal oxide can be used. The coating amount of the conductive metal oxide at this time is preferably 0.1 to 100 g per 1 m ² of the support of glass or polymer material. When a transparent conductive support is used, light is preferably incident from the support side. Examples of polymer materials that are preferably used include tetraacetyl cellulose (TAC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), syndiotactic polystyrene (SPS), polyphenylene sulfide (PPS), polycarbonate (PC), Examples include polyarylate (PAR), polysulfone (PSF), polyester sulfone (PES), polyetherimide (PEI), cyclic polyolefin, and brominated phenoxy. On the conductive support 1, the surface may be provided with a light management function. For example, an antireflection film in which high refractive films and low refractive index oxide films described in JP-A-2003-123859 are alternately laminated, The light guide function described in JP-A-2002-260746 is improved.

  In addition to this, a metal support can also be preferably used. Examples thereof include titanium, aluminum, copper, nickel, iron, stainless steel, and copper. These metals may be alloys. More preferably, titanium, aluminum, and copper are preferable, and titanium and aluminum are particularly preferable.

  It is preferable that the conductive support 1 has a function of blocking ultraviolet light. For example, a method in which a fluorescent material capable of changing ultraviolet light into visible light is present in the transparent support or on the surface of the transparent support, or a method using an ultraviolet absorber is also included.

  On the conductive support 1, a function described in JP-A-11-250944 may be further provided.

  Preferred conductive films include metals (eg, platinum, gold, silver, copper, aluminum, rhodium, indium, etc.), carbon, or conductive metal oxides (indium-tin composite oxide, tin oxide doped with fluorine, etc.) ).

  The thickness of the conductive film is preferably 0.01 to 30 μm, more preferably 0.03 to 25 μm, and particularly preferably 0.05 to 20 μm.

The conductive support 1 preferably has a lower surface resistance. The range of the surface resistance is preferably 50 Ω / cm ² or less, more preferably 10 Ω / cm ² or less. This lower limit is not particularly limited, but is usually about 0.1 Ω / cm ² .

  Since the resistance value of the conductive film increases as the cell area increases, a collecting electrode may be disposed. One or both of a gas barrier film and an ion diffusion preventing film may be disposed between the conductive support 1 and the transparent conductive film. As the gas barrier layer, a resin film or an inorganic film can be used.

  Moreover, you may provide a transparent electrode and a porous semiconductor electrode photocatalyst content layer. The transparent conductive film may have a laminated structure, and as a preferable method, for example, FTO can be laminated on ITO.

(D) Semiconductor Fine Particle As shown in FIG. 1, the photoelectric conversion element 10 of the present invention has a photosensitive layer 2 in which a sensitizing dye 21 is adsorbed on a porous semiconductor fine particle 22 on a conductive support 1. Is formed. As will be described later, for example, the photoreceptor layer 2 can be produced by immersing the dispersion of the semiconductor fine particles 22 on the conductive support 1 and then immersing it in the above dye solution.

  As the semiconductor fine particles 22, metal chalcogenides (for example, oxides, sulfides, selenides, etc.) or perovskite fine particles are preferably used. Preferred examples of the metal chalcogenide include titanium, tin, zinc, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium, tantalum oxide, cadmium sulfide, cadmium selenide, and the like. . Preferred perovskites include strontium titanate and calcium titanate. Of these, titanium oxide, zinc oxide, tin oxide, and tungsten oxide are particularly preferable.

In semiconductors, there are an n-type in which carriers involved in conduction are electrons and a p-type in which carriers are holes. In the element of the present invention, n-type is preferable in terms of conversion efficiency. In n-type semiconductors, in addition to intrinsic semiconductors (for example, intrinsic semiconductors) having no impurity level and equal carrier concentration due to conduction band electrons and valence band holes, the electron carrier concentration is reduced by structural defects derived from impurities. There are high n-type semiconductors. The n-type inorganic semiconductor preferably used in the present invention is TiO ₂ , TiSrO ₃ , ZnO, Nb ₂ O ₃ , SnO ₂ , WO ₃ , Si, CdS, CdSe, V ₂ O ₅ , ZnS, ZnSe, SnSe, KTaO. ₃ , FeS ₂ , PbS, InP, GaAs, CuInS ₂ , CuInSe ₂ and the like. Of these, the most preferred n-type semiconductors are TiO ₂ , ZnO, SnO ₂ , WO ₃ , and Nb ₂ O ₃ . A semiconductor material in which a plurality of these semiconductors are combined is also preferably used.

  The particle size of the semiconductor fine particles 22 is preferably such that the average particle size of the primary particles is 2 nm or more and 50 nm or less for the purpose of keeping the viscosity of the semiconductor fine particle dispersion high, and the average particle size of the primary particles is 2 nm or more and 30 nm or less. More preferably, it is an ultrafine particle. Two or more kinds of fine particles having different particle size distributions may be mixed. In this case, the average size of the small particles is preferably 5 nm or less. In addition, for the purpose of scattering incident light and improving the light capture rate, large particles having an average particle size exceeding 50 nm can be added to the ultrafine particles at a low content, or another layer can be applied. In this case, the content of the large particles is preferably 50% or less, more preferably 20% or less of the mass of particles having an average particle size of 50 nm or less. The average particle size of the large particles added and mixed for the above purpose is preferably 100 nm or more, and more preferably 250 nm or more. The upper limit value of the average particle size of the large particles is preferably 500 nm from the viewpoint of effectively utilizing the light scattering effect. By controlling the average particle size as described above, the haze ratio can be 60% or more.

  In the present invention, it was surprisingly found that conversion efficiency and durability were improved by using the dye represented by the general formula (1) of the present invention for a semiconductor film having a haze ratio of 60% or more.

The photoreceptor layer preferably has a multilayer structure in which the porous photoelectric conversion layer has two or more layers. The semiconductor fine particles 22 forming the porous semiconductor layer of the photoreceptor layer 2 have different average particle sizes in the respective layers. Furthermore, the porous semiconductor layer of the photoreceptor layer 2 having a multilayer structure is arranged from the light receiving surface side in the order of the layer formed by the semiconductor fine particles 22 having a small average particle diameter to the layer formed by the semiconductor fine particles 22 having a large average particle diameter. It is preferable that
Furthermore, the porous semiconductor layer located on the light-receiving surface side of the porous semiconductor layer in the multilayered photosensitive layer 2 is preferably formed of semiconductor fine particles 22 having a variation coefficient of particle size distribution of 10 or less. The coefficient of variation is preferably 0.1 to 10, more preferably 0.2 to 8, and further preferably 0.3 to 7.
In addition, the porous semiconductor layer of the photoreceptor layer 2 having a multilayer structure receives light in the order of the layer having the maximum sensitivity wavelength region in the absorption spectrum on the short wavelength side to the layer having the maximum sensitivity wavelength region in the absorption spectrum on the long wavelength side. It is preferable to arrange from the surface side. For example, the photosensitive layer 2 having a multilayer structure has, from the light receiving portion side, a first semiconductor fine particle layer having a maximum sensitivity wavelength of 400 nm to 500 nm adsorbed with a merocyanine dye S-2 described later, and a maximum sensitivity wavelength of 500 nm. Represented by the above general formula (1) which is ˜700 nm, for example, a second one in which any one of the dyes A-1 to A-7, A-9, A-11, A-13 to A-17 is adsorbed The semiconductor fine particle layers are stacked in this order.
In the present invention, the average particle diameter of the semiconductor fine particles refers to a value measured using a laser diffraction particle size distribution analyzer SALD-3100 manufactured by Shimadzu Corporation. The variation coefficient of the particle size distribution was obtained from the following equation using the obtained average value and standard deviation data.
Coefficient of variation = (standard deviation) ÷ (average value)

  It is preferable to use a haze ratio of 60% or more by using particles having a large average particle diameter for light scattering. The haze ratio is expressed by (diffuse transmittance) / (total light transmittance). In order to control the haze ratio, there are a method of changing the dispersion time of the semiconductor fine particles, a method of mixing particles having the same or different material as the porous semiconductor layer and having a large particle diameter.

The photoreceptor layer having a multilayer structure is preferably prepared by a method including the following steps (a) to (d).
(A) a step of preparing a dispersion A (including a colloidal liquid) containing semiconductor fine particles having an average particle diameter of 5 nm to 50 nm;
(B) creating a dispersion B (including colloidal liquid) containing semiconductor fine particles having an average particle diameter of 100 nm to 500 nm;
(C) forming a first photoreceptor layer from the dispersion A,
(D) and a step of forming a second photosensitive layer from the dispersion B.

In the step (b), the prepared dispersion B may contain 5% by mass to 90% by mass of semiconductor fine particles having an average particle size of 5 nm to 50 nm in addition to the semiconductor fine particles having an average particle size of 100 nm to 500 nm. A preferable content of the semiconductor fine particles having an average particle diameter of 5 nm to 50 nm in the dispersion B is 5% by mass to 50% by mass of the total content of the semiconductor fine particles.
The size of the semiconductor fine particles affects the size of the scattering. If the particle size is large, the diffraction angle of light is large, the amount of light transmitted through the porous photoelectric conversion layer is reduced, and more light is used. Compared to the dyes used so far, the dye represented by the general formula (1) is considered to have increased the efficiency of use of scattered light because of its large extinction coefficient on the long wavelength side where it is easily scattered.

  The method for producing the semiconductor fine particles 22 is preferably the gel-sol method described in Sakuo Sakuo's “Science of Sol-Gel Method”, Agne Jofu Co., Ltd. (1998). Also preferred is a method of producing an oxide by high-temperature hydrolysis of chloride developed by Degussa in an oxyhydrogen salt. When the semiconductor fine particles 22 are titanium oxide, the sol-gel method, the gel-sol method, and the high-temperature hydrolysis method in oxyhydrogen salt of chloride are all preferable. It is also possible to use the sulfuric acid method and the chlorine method described in Gihodo Publishing (1997). Further, as the sol-gel method, the method described in Journal of American Ceramic Society, Vol. 80, No. 12, 3157-3171 (1997), or the chemistry of Burnside et al. The method described in Materials, Vol. 10, No. 9, pages 2419-2425 is also preferable.

  In addition to this, as a method for producing semiconductor fine particles, for example, as a method for producing titania nanoparticles, preferably, a method by flame hydrolysis of titanium tetrachloride, a combustion method of titanium tetrachloride, hydrolysis of a stable chalcogenide complex, orthotitanic acid Hydrolysis of the soluble part, formation of fine semiconductor particles from soluble and insoluble parts, dissolution and removal of soluble part, hydrothermal synthesis of peroxide aqueous solution, or production of core / shell structured titanium oxide fine particles by sol-gel method A method is mentioned.

  Examples of the crystal structure of titania include anatase type, brookite type, and rutile type, and anatase type and brookite type are preferable.

  Titania nanotubes, nanowires, and nanorods may be mixed with titania fine particles.

  Titania may be doped with a nonmetallic element or the like. In addition to the dopant as an additive to titania, an additive may be used on the surface to improve the necking or to prevent reverse electron transfer. Examples of preferred additives include ITO, SnO particles, whiskers, fibrous graphite / carbon nanotubes, zinc oxide necking binders, fibrous materials such as cellulose, metals, organic silicon, dodecylbenzenesulfonic acid, silane compounds, etc. Examples thereof include a mobile binding molecule and a potential gradient dendrimer.

  For the purpose of removing surface defects on titania, titania may be acid-base or redox treated before dye adsorption. Etching, oxidation treatment, hydrogen peroxide treatment, dehydrogenation treatment, UV-ozone, oxygen plasma, or the like may be used.

(E) Semiconductor fine particle dispersion In the present invention, a semiconductor fine particle dispersion in which the solid content other than the semiconductor fine particles is 10% by mass or less of the entire semiconductor fine particle dispersion is applied to the conductive support 1, A porous semiconductor fine particle coating layer can be obtained by heating to a high temperature.

  In addition to the sol-gel method described above, a method of preparing a semiconductor fine particle dispersion is a method of depositing fine particles in a solvent and using them as they are when synthesizing a semiconductor. Ultrafine particles are irradiated with ultrasonic waves. Or a method of mechanically pulverizing and grinding using a mill or a mortar. As the dispersion solvent, one or more of water and various organic solvents can be used. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropyl alcohol, citronellol and terpineol, ketones such as acetone, esters such as ethyl acetate, dichloromethane, acetonitrile and the like.

  At the time of dispersion, a small amount of, for example, a polymer such as polyethylene glycol, hydroxyethyl cellulose, carboxymethyl cellulose, a surfactant, an acid, or a chelating agent may be used as a dispersion aid. However, most of these dispersing aids are preferably removed by a filtration method, a method using a separation membrane, a centrifugal method or the like before the step of forming a film on a conductive support. In the semiconductor fine particle dispersion, the solid content other than the semiconductor fine particles can be 10% by mass or less of the total dispersion. This concentration is preferably 5% or less, more preferably 3% or less, and particularly preferably 1% or less. More preferably, it is 0.5% or less, and particularly preferably 0.2%. That is, in the semiconductor fine particle dispersion, the solid content other than the solvent and the semiconductor fine particles can be 10% by mass or less of the entire semiconductor fine dispersion. It is preferable to consist essentially of semiconductor fine particles and a dispersion solvent.

If the viscosity of the semiconductor fine particle dispersion is too high, the dispersion will aggregate and cannot be formed into a film. Conversely, if the viscosity of the semiconductor fine particle dispersion is too low, the liquid will flow and cannot be formed into a film. is there. Therefore, the viscosity of the dispersion is preferably 10 to 300 N · s / m ² at 25 ° C. More preferably, it is 50 to 200 N · s / m ² at 25 ° C.

  As a method for applying the semiconductor fine particle dispersion, a roller method, a dip method, or the like can be used as an application method. Moreover, an air knife method, a blade method, etc. can be used as a metering method. Further, the application system method and the metering system method can be made the same part. The wire bar method disclosed in Japanese Patent Publication No. 58-4589, the slide hopper method described in US Pat. No. 2,681,294, etc., the extrusion The method and the curtain method are preferable. It is also preferable to apply by a spin method or a spray method using a general-purpose machine. As the wet printing method, intaglio, rubber plate, screen printing and the like are preferred, including the three major printing methods of letterpress, offset and gravure. From these, a preferred film forming method is selected according to the liquid viscosity and the wet thickness. Further, since the semiconductor fine particle dispersion of the present invention has a high viscosity and has a viscous property, it may have a strong cohesive force and may not be well adapted to the support during coating. In such a case, by performing cleaning and hydrophilization of the surface by UV ozone treatment, the binding force between the applied semiconductor fine particle dispersion and the surface of the conductive support 1 is increased, and it becomes easy to apply the semiconductor fine particle dispersion. .

The preferred thickness of the entire semiconductor fine particle layer is 0.1 μm to 100 μm. The thickness of the semiconductor fine particle layer is further preferably 1 μm to 30 μm, and more preferably 2 μm to 25 μm. The amount of the semiconductor fine particles supported per 1 m ² of the support is preferably 0.5 g to 400 g, and more preferably 5 g to 100 g.

  The applied semiconductor fine particle layer is subjected to heat treatment in order to enhance the electronic contact between the semiconductor fine particles and to improve the adhesion to the support and to dry the applied semiconductor fine particle dispersion. . By this heat treatment, a porous semiconductor fine particle layer can be formed.

  In addition to heat treatment, light energy can also be used. For example, when titanium oxide is used as the semiconductor fine particles 22, the surface may be activated by applying light absorbed by the semiconductor fine particles 22 such as ultraviolet light, or only the surface of the semiconductor fine particles 22 is activated by laser light or the like. Can be By irradiating the semiconductor fine particles 22 with light absorbed by the fine particles, the impurities adsorbed on the particle surfaces are decomposed by the activation of the particle surfaces, and can be brought into a preferable state for the above purpose. When the heat treatment and ultraviolet light are combined, the heating is preferably performed at 100 ° C. or higher and 250 ° C. or lower, or preferably 100 ° C. or higher and 150 ° C. or lower, while irradiating the semiconductor fine particles 22 with light absorbed by the fine particles. . Thus, by photoexciting the semiconductor fine particles 22, impurities mixed in the fine particle layer can be washed by photolysis, and physical bonding between the fine particles can be strengthened.

  In addition, the semiconductor fine particle dispersion may be applied to the conductive support 1, and other treatments may be performed in addition to heating and light irradiation. Examples of preferred methods include energization and chemical treatment.

  A pressure may be applied after application, and examples of a method for applying pressure include Japanese Patent Application Publication No. 2003-500857. Examples of light irradiation include JP-A No. 2001-357896. Examples of plasma, microwave, and energization include JP-A-2002-353453. Examples of the chemical treatment include JP-A-2001-357896.

  As the method for coating the semiconductor fine particles 22 on the conductive support 1, the semiconductor fine particles 22 described in Japanese Patent No. 2664194 can be used in addition to the method of applying the semiconductor fine particle dispersion on the conductive support 1. It is possible to use a method such as a method in which the precursor is applied on the conductive support 1 and hydrolyzed with moisture in the air to obtain a semiconductor fine particle film.

Examples of the precursor include (NH ₄ ) ₂ TiF ₆ , titanium peroxide, metal alkoxide / metal complex / metal organic acid salt, and the like.

  Also, a method of forming a semiconductor film by applying a slurry in which a metal organic oxide (such as an alkoxide) coexists, and heat treatment, light treatment, etc., a slurry in which an inorganic precursor coexists, titania dispersed in the pH of the slurry The method which specified the property of particle | grains is mentioned. A binder may be added to these slurries in a small amount, and examples of the binder include cellulose, fluoropolymer, crosslinked rubber, polybutyl titanate, carboxymethyl cellulose and the like.

  Examples of the technology relating to the formation of the semiconductor fine particles 22 or the precursor layer thereof include a method of hydrophilizing by a physical method such as corona discharge, plasma, and UV, a chemical treatment with alkali, polyethylenedioxythiophene and polystyrenesulfonic acid, polyaniline, etc. Forming an intermediate film for bonding.

  As a method of coating the semiconductor fine particles 22 on the conductive support 1, (2) dry method and (3) other methods may be used in combination with the above (1) wet method. (2) As a dry method, JP 2000-231943 A is preferable. (3) As other methods, JP-A-2002-134435 is preferable.

  Examples of the dry method include vapor deposition, sputtering, and aerosol deposition method. Further, electrophoresis or electrodeposition may be used.

  Moreover, after producing a coating film once on a heat-resistant board | substrate, you may use the method of transferring to films, such as a plastics. Preferably, a method for transferring via EVA described in JP-A No. 2002-184475, a semiconductor layer / conductive layer on a sacrificial substrate containing an inorganic salt that can be removed with ultraviolet rays and an aqueous solvent described in JP-A No. 2003-98977 And a method of removing the sacrificial substrate after transfer to an organic substrate.

  The semiconductor fine particles 22 preferably have a large surface area so that many sensitizing dyes 21 can be adsorbed. For example, in a state where the semiconductor fine particles 22 are coated on the conductive support 1, the surface area thereof is preferably 10 times or more, more preferably 100 times or more the projected area. Although there is no restriction | limiting in particular in this upper limit, Usually, it is about 5000 times. As a preferable structure of the semiconductor fine particles 22, JP 2001-93591 A and the like can be mentioned.

  In general, as the thickness of the semiconductor fine particle layer increases, the amount of the sensitizing dye 21 that can be carried per unit area increases, so that the light absorption efficiency increases. However, the loss due to charge recombination increases because the diffusion distance of the generated electrons increases. Become. The preferred thickness of the semiconductor fine particle layer varies depending on the use of the device, but is typically 0.1 μm to 100 μm. When used as a photoelectrochemical cell, the thickness is preferably 1 μm to 50 μm, more preferably 3 μm to 30 μm. The semiconductor fine particles may be heated at a temperature of 100 ° C. to 800 ° C. for 10 minutes to 10 hours in order to bring the particles into close contact after being applied to the support. When glass is used as the support, the film forming temperature is preferably 400 ° C to 600 ° C.

  When a polymer material is used as the support, it is preferable to heat after film formation at 250 ° C. or lower. In this case, the film forming method may be any one of (1) a wet method, (2) a dry method, and (3) an electrophoresis method (including an electrodeposition method), preferably (1) a wet method, or ( 2) A dry method, more preferably (1) a wet method.

The coating amount of the semiconductor fine particles 22 per 1 m ² of the support is preferably 0.5 g to 500 g, more preferably 5 g to 100 g.

  In order to adsorb the sensitizing dye 21 to the semiconductor fine particles 22, it is preferable to immerse the well-dried semiconductor fine particles 22 in a dye adsorbing dye solution comprising the solution and the dye according to the present invention for a long time. The solution used for the dye solution for dye adsorption can be used without particular limitation as long as it can dissolve the sensitizing dye 21 according to the present invention. For example, ethanol, methanol, isopropanol, toluene, t-butanol, acetonitrile, acetone, n-butanol and the like can be used. Among these, ethanol and toluene can be preferably used.

  The dye solution for dye adsorption comprising the solution and the dye of the present invention may be heated to 50 ° C. to 100 ° C. as necessary. Adsorption of the sensitizing dye 21 may be performed before or after the application of the semiconductor fine particles 22. Alternatively, the semiconductor fine particles 22 and the sensitizing dye 21 may be applied and adsorbed simultaneously. Unadsorbed sensitizing dye 21 is removed by washing. When baking a coating film, it is preferable to adsorb | suck the sensitizing dye 21 after baking. It is particularly preferable that the sensitizing dye 21 is quickly adsorbed after baking and before water is adsorbed on the coating film surface. The sensitizing dye 21 to be adsorbed may be one kind of the dye A1 described above, or may be mixed with another dye. The dye to be mixed is selected so as to make the wavelength range of photoelectric conversion as wide as possible. When mixing the dyes, it is preferable to prepare a dye solution for dye adsorption by dissolving all the dyes.

The total amount of the sensitizing dye 21 used is preferably from 0.01 mmol to 100 mmol, more preferably from 0.1 mmol to 50 mmol, and particularly preferably from 0.1 mmol to 10 mmol, per 1 m ² of the support. . In this case, the amount of the sensitizing dye 21 according to the present invention is preferably 5 mol% or more.

  Further, the adsorption amount of the sensitizing dye 21 to the semiconductor fine particles 22 is preferably 0.001 mmol to 1 mmol, more preferably 0.1 to 0.5 mmol, with respect to 1 g of the semiconductor fine particles.

  By using such a dye amount, a sensitizing effect in a semiconductor can be sufficiently obtained. On the other hand, when the amount of the dye is small, the sensitizing effect is insufficient, and when the amount of the dye is too large, the dye not attached to the semiconductor floats and causes the sensitizing effect to be reduced.

  Further, a colorless compound may be co-adsorbed for the purpose of reducing the interaction between dyes such as association. Examples of the hydrophobic compound to be co-adsorbed include steroid compounds having a carboxyl group (for example, cholic acid and pivaloyl acid).

  After adsorbing the sensitizing dye 21, the surface of the semiconductor fine particles 22 may be treated with amines. Preferred amines include 4-tert-butyl pyridine, polyvinyl pyridine and the like. These may be used as they are in the case of a liquid, or may be used by dissolving in an organic solvent.

  The counter electrode 4 functions as a positive electrode of the photoelectrochemical cell. The counter electrode 4 is usually synonymous with the conductive support 1 described above, but a support for the counter electrode is not necessarily required in a configuration in which the strength is sufficiently maintained. However, having a support is advantageous in terms of hermeticity. Examples of the material for the counter electrode 4 include platinum, carbon, and conductive polymer. Preferable examples include platinum, carbon, and conductive polymer.

  The structure of the counter electrode 4 is preferably a structure having a high current collecting effect. Preferable examples include JP-A-10-505192.

A composite electrode such as titanium oxide and tin oxide (TiO ₂ / SnO ₂ ) may be used as the light receiving electrode 5, and as a mixed electrode of titania, for example, Japanese Patent Application Laid-Open No. 2000-119393 may be cited. Examples of mixed electrodes other than titania include JP-A Nos. 2001-185243 and 2003-282164.

  The photoelectric conversion element may have a structure in which a first electrode layer, a first photoelectric conversion layer, a conductive layer, a second photoelectric conversion layer, and a second electrode layer are sequentially stacked. In this case, the dyes used for the first photoelectric conversion layer and the second photoelectric conversion layer may be the same or different, and if they are different, it is preferable that the absorption spectra are different.

  The light receiving electrode 5 may be a tandem type in order to increase the utilization rate of incident light. Preferred examples of the tandem type configuration include those described in JP-A Nos. 2000-90989 and 2002-90989.

  A light management function for efficiently performing light scattering and reflection inside the layer of the light receiving electrode 5 may be provided. Preferably, the thing of Unexamined-Japanese-Patent No. 2002-93476 is mentioned.

  It is preferable to form a short-circuit prevention layer between the conductive support 1 and the porous semiconductor fine particle layer in order to prevent a reverse current due to direct contact between the electrolyte and the electrode. Preferable examples include Japanese Patent Application Laid-Open No. 06-507999.

  In order to prevent contact between the light receiving electrode 5 and the counter electrode 4, it is preferable to use a spacer or a separator. A preferable example is JP-A No. 2001-283941.

  Cell and module sealing methods include polyisobutylene thermosetting resin, novolak resin, photo-curing (meth) acrylate resin, epoxy resin, ionomer resin, glass frit, method using aluminum alkoxide for alumina, low melting point glass paste It is preferable to use a laser melting method. When glass frit is used, powder glass mixed with acrylic resin as a binder may be used.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these.

(Preparation of dye)
The dyes A-1 to A-7 of the general formula (1) shown in the specific examples were prepared by the method described in JP-A No. 2001-291534.

(Measurement of maximum absorption wavelength of dye)
The maximum absorption wavelengths of the dyes A-1 to A-7 were measured. The results are shown in Table 1. The measurement was performed with a spectrophotometer (U-4100 (trade name), manufactured by Hitachi High-Tech), and the solution was adjusted to a concentration of 2 μM using THF: ethanol = 1: 1.

[Experiment 1]
(1) Formation of semiconductor fine particle layer (first semiconductor fine particle layer) on the light receiving surface side 125 ml of titanium isopropoxide was dropped into 750 ml of 0.1M nitric acid aqueous solution (manufactured by Kishida Chemical Co., Ltd.) and heated at 80 ° C. for 8 hours. Then, a sol solution was prepared by a hydrolysis reaction. The obtained sol solution is kept at 250 ° C. for 15 hours in a titanium autoclave for particle growth, and then subjected to ultrasonic dispersion for 30 minutes to obtain a colloidal solution containing titanium oxide particles having an average primary particle size of 20 nm. It was.

  The obtained colloidal solution containing titanium oxide particles is slowly concentrated with an evaporator until the titanium oxide has a concentration of 10 wt%, and then polyethylene glycol (manufactured by Kishida Chemical Co., Ltd., weight average molecular weight: 200000) is added to the titanium oxide. Suspension A in which titanium oxide particles were dispersed was obtained by adding 40% by weight to the mixture and stirring.

The prepared titanium oxide suspension is applied to the transparent conductive film side of the glass substrate (conductive support 1) on which the SnO ₂ film is formed as the transparent conductive film by a doctor blade method, and a coating film having an area of about 10 mm × 10 mm is formed. Obtained. This coating film was preliminarily dried at 120 ° C. for 30 minutes and further baked at 500 ° C. for 30 minutes in an oxygen atmosphere to form a semiconductor fine particle layer on the light receiving surface side having a thickness of about 10 μm.

(2) Formation of Second Semiconductor Fine Particle Layer Next, commercially available titanium oxide fine particles (manufactured by Teika, product name: TITANIX JA-1, particle size of about 180 nm) and magnesium oxide powder (manufactured by Kishida Chemical Co., Ltd.) ) 0.4 g was added to 20 ml of distilled water and adjusted to pH = 1 with hydrochloric acid. Further, zirconia beads were added, and this mixed solution was subjected to a dispersion treatment with a paint shaker for 8 hours. Then, 40% of polyethylene glycol (manufactured by Kishida Chemical Co., Ltd., weight average molecular weight: 200000) was added in a weight ratio with respect to titanium oxide and stirred to obtain suspension B in which titanium oxide particles were dispersed.

  The titanium oxide suspension B was applied on the light-receiving surface side semiconductor fine particle layer formed on the glass substrate prepared in (1) by the doctor blade method to obtain a coating film. This coating film was preliminarily dried at 80 ° C. for 20 minutes and further baked at about 500 ° C. for 60 minutes in an oxygen atmosphere to form a second semiconductor fine particle layer having a thickness of about 22 μm. When the haze ratio of the layer (referred to as T1) in which the second semiconductor fine particle layer was formed on the first semiconductor fine particle layer was measured, it was 84%. The haze ratio was measured according to JIS K7105 using a haze / transmittance / reflectometer HR-100 manufactured by Murakami Color Research Laboratory. The haze ratio was measured by the same method for other samples.

  Also, the suspension AB2 (A: B = 2) in which the suspension A and the suspension B are mixed at a specific ratio on the light-receiving surface side semiconductor fine particle layer formed on the glass substrate prepared in (1). : Suspension AB3 (A: B = 4: 6), Suspension AB4 (A: B = 6: 4), and Suspension AB5 (A: B = 8: 2) are the same as T1 Samples of the titanium oxide bilayer film on which the second semiconductor fine particle layer was formed by the method described above were designated as T2 to T5.

(3) Production of photoelectrochemical cell As a dye (first dye) having a maximum sensitivity absorption wavelength region in the absorption spectrum on the short wavelength side, the following merocyanine dye S-2 is dissolved in ethanol to a concentration of 3 × 10 ^A dye solution for adsorption of ^-4 mol / liter of the first dye was prepared.

  A glass substrate (referred to as G1 to G5) provided with a transparent conductive film and a semiconductor fine particle layer (in which a second semiconductor fine particle layer is formed on the first semiconductor fine particle layer; T1 to T5) is about 50 ° C. The first dye was adsorbed on the porous semiconductor layer by immersing in a dye solution for adsorbing the first dye heated to 10 minutes. Thereafter, the glass substrate was washed several times with absolute ethanol and dried at about 60 ° C. for about 20 minutes. Next, the glass substrate was immersed in 0.5N hydrochloric acid for about 10 minutes, and the first dye was adsorbed on the second porous semiconductor layer. Thereafter, the excess was washed with ethanol to remove excess first dye. Furthermore, the glass substrate was dried at about 60 ° C. for about 20 minutes.

Next, as the dye having the maximum sensitivity absorption wavelength region in the absorption spectrum (second dye) on the long wavelength side, the dye A-1 of the present invention is dissolved in ethanol, and the concentration is 3 × 10 ⁻⁴ mol / liter. A dye solution for adsorption of two dyes was prepared.

  The glass substrate (G1) provided with the transparent conductive film and the porous semiconductor layer was immersed in the dye solution for adsorbing the second dye at room temperature and normal pressure for 15 minutes to adsorb the second dye on the porous semiconductor layer. . Thereafter, the glass substrate was washed several times with absolute ethanol and dried at about 60 ° C. for about 20 minutes. Here, the haze ratio of the porous semiconductor layer was measured and found to be 85%. The same operation was performed for G2 to G5, and the results of measuring the haze ratio are shown in Table 2.

  Next, in 3-methoxypropionitrile solvent, dimethylpropylimidazolium iodide has a concentration of 0.5 mol / liter, lithium iodide has a concentration of 0.1 mol / liter, and iodine has a concentration of 0.05 mol / liter. Thus, a redox electrolyte solution was prepared. The porous semiconductor layer side of the glass substrate provided with the porous semiconductor layer on which the first dye and the second dye are adsorbed is opposed to the platinum side of the counter electrode support made of ITO glass having platinum as a counter electrode. The redox electrolyte prepared in the meantime was injected, and the periphery was sealed with an epoxy resin sealing material to prepare a photoelectrochemical cell of Sample 1-1.

  Photoelectrochemical cells of sample numbers 1-2 to 1-18 were prepared in the same manner except that G1 was changed to G2 to G5 and the second dye was changed to the dye described in Table 2. The results of measuring the haze ratio of the semiconductor fine particle layer used in these photoelectrochemical cells are shown in Table 2.

  Further, a semiconductor fine particle layer was formed using the same second semiconductor fine particle layer and first semiconductor fine particle layer. That is, the first semiconductor fine particle layer and the second semiconductor fine particle layer were formed using the titanium oxide suspension A used for forming the first semiconductor fine particle layer in the sample number 1-1 (this A semiconductor fine particle layer having a multilayer structure is designated as T6). Except for using T2, the second dye was changed in the same manner as shown in Table 2 to prepare photoelectrochemical cells of sample numbers 1-21 to 1-22.

  The results of evaluating the obtained solar cell under measurement conditions: AM-1.5 (100 mW / cm 2) are shown in Table 2 in terms of conversion efficiency. Table 2 shows the reduction rate of the conversion efficiency examined after aging for 200 hours at 80 ° C. and 85% RH in a dark place. As a result, the conversion efficiency decrease rate of less than 3% was indicated as ◎, 3% or more and less than 5% as 、 ５, 5% or more and less than 10% as Δ, or 10% or more as x.

  In the photoelectric conversion element and the photoelectrochemical cell of the present invention, the porous photoelectric conversion layer has a multilayer structure, and the haze ratio at a wavelength in the visible light region of the porous semiconductor layer is 60% or more. By the improvement, a photoelectric conversion element and a photoelectrochemical cell having high conversion efficiency and excellent durability can be obtained.

  Further, by using the semiconductor fine particles 22 having a small average particle diameter to form the first porous semiconductor layer located on the light receiving surface side, and reducing the scattering of long wavelength light, the porous semiconductor layers after the second layer are formed. As a photoelectric conversion element, high photoelectric conversion efficiency can be obtained. Further, since the porous semiconductor layer located on the light receiving surface side is formed of semiconductor fine particles having a variation coefficient of the particle size distribution of 10 or less, an effect that the photoelectric conversion efficiency is further improved can be obtained.

  Furthermore, the photoelectric conversion efficiency excellent as a photoelectric conversion element can be obtained by scattering light in the porous semiconductor layer after the second layer. And the porous semiconductor layer having a multilayer structure is arranged from the light receiving surface side in the order of the layer having the maximum sensitivity wavelength region in the absorption spectrum on the short wavelength side and the layer having the maximum sensitivity wavelength region in the absorption spectrum on the long wavelength side. Therefore, it is possible to photoelectrically convert short-wavelength light that is easily absorbed on the light-receiving surface side, and to convert long-wavelength light that can reach the inside of the multilayer structure on the inner side. It can spread and use sunlight effectively, and high photoelectric conversion efficiency can be obtained as a photoelectric conversion element by improving current density.

DESCRIPTION OF SYMBOLS 1 Conductive support body 2 Photosensitive layer 21 Sensitizing dye 22 Semiconductor fine particle 3 Charge transfer body layer 4 Counter electrode 5 Photosensitive electrode 6 External circuit 10 Photoelectric conversion element 100 Photoelectrochemical cell

Claims (14)

A photoelectric conversion element comprising a conductive support, a photosensitive layer composed of a porous semiconductor layer containing a dye, a charge transfer layer, and a counter electrode,
The photoreceptor layer has a multilayer structure, the porous semiconductor layer contains at least one dye represented by the following general formula (1), and the haze ratio at a wavelength in the visible light region of the porous semiconductor layer is A photoelectric conversion element characterized by being 60% or more.
Mz (LL ¹ ) _m1 (LL ² ) _m2 (X) _m3 · CI (1)
[Mz represents a metal atom, LL ¹ is a bidentate or tridentate ligand represented by the following general formula (2), and LL ² has a substituent represented by the following general formula (3). It may be a bidentate or tridentate ligand.
m1 represents an integer of 0 to 3, and when m1 is 2 or more, LL1 may be the same or different. m2 represents an integer of 0 to 2, LL ² when m2 is 2 may be the same or different. However, one of m1 and m2 is an integer of 1 or more. m3 represents an integer of 0 to 3.
X represents a ligand, an acyloxy group, an acylthio group, a thioacyloxy group, a thioacylthio group, an acylaminooxy group, a thiocarbamate group, a dithiocarbamate group, a thiocarbonate group, a dithiocarbonate group, a trithiocarbonate group, A monodentate or bidentate arrangement coordinated by a group selected from the group consisting of an acyl group, a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group, an alkylthio group, an arylthio group, an alkoxy group, and an aryloxy group. A ligand or a monodentate or bidentate ligand composed of a halogen atom, carbonyl, dialkyl ketone, 1,3-diketone, carbonamide, thiocarbonamide or thiourea. ]

[In General Formula (2), R ¹⁰¹ and R ¹⁰² each independently represent a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group, or a phosphonyl group. R ¹⁰³ and R ¹⁰⁴ each independently represent a substituent, and R ¹⁰⁵ and R ¹⁰⁶ each independently represent one or more of an alkyl group, an aryl group, and a heterocyclic group.
L ¹ and L ² each independently represent a conjugated chain composed of an ethenylene group and an ethynylene group.
a1 and a2 each independently represent an integer of 0 to 3, R ¹⁰¹ may be the same or different when a1 is 2 or more, and R ¹⁰² may be the same or different when a2 is 2 or more, b1 And b2 each independently represents an integer of 0 to 3. When b1 is 2 or more, R ³ may be the same or different, R ³ may be connected to each other to form a ring, and when b2 is 2 or more, R 4 may be the same or different and are connected to each other. may form a ring Te may be 1 or more when b1 and b2 are both linked and the ^{R 103} and ^{R 104} form a ring, d1 and d2 each independently represent an integer of 0 to 5 , D3 represents 0 or 1. ]

[In General Formula (3), Za, Zb, and Zc each independently represent a nonmetallic atom group that can form a 5- or 6-membered ring, and c represents 0 or 1. ]   The photoelectric conversion element according to claim 1, wherein M in the general formula (1) is Ru, Fe, Os, or Cu.   3. The photoelectric conversion element according to claim 2, wherein M in the general formula (1) is Ru. LL ¹ in the general formula (1) is a bidentate or tridentate ligand represented by the following general formula (4-1), (4-2) or (4-3), The photoelectric conversion element according to any one of claims 1 to 3.

[R ¹⁰¹ , R ¹⁰² and R ¹⁰⁷ each independently represent a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group or a phosphonyl group. R ¹⁰³ , R ¹⁰⁴ , R ¹⁰⁸ , R ¹²⁵ , R ¹²⁶ , R ¹²⁷ and R ¹²⁸ each independently represent a substituent. R ^{121 to} R ¹²⁴ each independently represent hydrogen, an alkyl group, an alkenyl group, or an aryl group. R ¹²¹ and R ^{122 and} R ¹²³ and R ¹²⁴ may be connected to each other to form a ring. a1, a2 and a3 each independently represents an integer of 0 to 3; When a1 is 2 or more, R ¹⁰¹ may be the same or different. a2 is ^{R 102} when 2 or more may be the same or different. a3 is the ^{R 107} when two or more may be the same or different. b1 and b2 each independently represents an integer of 0 to 3. When b1 is 2 or more, R ¹⁰³ may be the same or different, and may be linked to each other to form a ring. When b2 is 2 or more, R ¹⁰⁴ may be the same or different and may be connected to each other to form a ring. b3 represents an integer of 0 to 5, and when b3 is 2 or more, R ¹⁰⁸ may be the same or different, and may be connected to each other to form a ring.
When b1 and b2 in the general formula (4-1) are both 1 or more, R ¹⁰³ and R ¹⁰⁴ may be linked to form a ring. When b1 and b3 in the general formula (4-2) are both 1 or more, R ¹⁰³ and R ¹⁰⁸ may be linked to form a ring. d1 and d2 each independently represents an integer of 0 to 4. When d1 is 1 or more, R ¹²⁵ may be linked to one or both of R ¹²¹ and R ¹²² to form a ring, and when d1 is 2 or more, R ¹²⁵ may be the same or different, and They may be linked to form a ring. When d2 is 1 or more, R ¹²⁶ may be linked to one or both of R ¹²³ and R ¹²⁴ to form a ring, and when d2 is 2 or more, R ¹²⁶ may be the same or different, and They may be linked to form a ring. d3 represents 0 or 1. ] Either one or both of R ¹²¹ and R ^{122 in} the general formulas (4-1) and (4-2) is an alkyl group substituted with an alkoxy group. The photoelectric conversion element of Claim 1. The LL ² in the general formula (1) is a bidentate or tridentate ligand represented by any one of the following general formulas (5-1) to (5-8). The photoelectric conversion element of any one of 1-5.

[R ^{151 to} R ¹⁵⁸ each independently represent a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group or a phosphonyl group, R ^{159 to} R ¹⁶⁵ each independently represent a substituent, and R ¹⁵¹ to R ^{158 166} may be bonded to any position on the ring, and R ^{167 to} R ¹⁷¹ each independently represent hydrogen, an alkyl group, an alkenyl group, or an aryl group. e1 to e8, e13, e14 and e16 each independently represents an integer of 0 to 4, e9 to e12 and e15 each independently represents an integer of 0 to 6, and when e1 to e8 is 2 or more, R ¹⁵¹ to R ¹⁵⁸ may be the same as or different from each other. When e9 to e16 are 2 or more, R ^{159 to} R ¹⁶⁶ may be the same or different from each other and may be linked to each other to form a ring. ] In the general formula (1), m1 is 1, m2 is 1, m3 is 1 or 2, and LL ² is a bidentate or tridentate arrangement represented by the general formula (5-1). It is a ligand, The photoelectric conversion element of any one of Claims 1-6 characterized by the above-mentioned.   The said pigment | dye has at least 1 sort (s) chosen from the group which consists of a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group, and a phosphonyl group, In any one of Claims 1-7 characterized by the above-mentioned. The photoelectric conversion element as described.   The photoelectric conversion element according to claim 1, wherein the semiconductor fine particles constituting the photoconductor are titanium oxide fine particles.   10. The photoelectric conversion device according to claim 1, wherein the semiconductor fine particles forming each layer of the multi-layered photosensitive layer have different average particle sizes.   11. The average particle diameter of the semiconductor fine particle layer on the light receiving surface side of the photosensitive layer having the multilayer structure is made smaller than the average particle diameter of the semiconductor fine particle layer. Photoelectric conversion element.   The porous semiconductor layer located on the light-receiving surface side of the porous semiconductor layer of the multilayered photosensitive layer is formed of semiconductor fine particles having a variation coefficient of particle size distribution of 10 or less. 11. The photoelectric conversion element according to any one of 11 above.   The porous semiconductor layer of the multi-layered photosensitive layer is formed from the light receiving surface side in the order of the layer having the maximum sensitivity wavelength region in the absorption spectrum on the short wavelength side and the layer having the maximum sensitivity wavelength region in the absorption spectrum on the long wavelength side. It is arrange | positioned, The photoelectric conversion element of any one of Claims 1-12 characterized by the above-mentioned.   A photoelectrochemical cell comprising the photoelectric conversion device according to claim 1.

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