JP2015013928A - Dye and dye-sensitized solar cell using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal complex dye having new structure and sensitivity in a wide range of light and excellent in stability, and a dye-sensitized solar cell and the like using the dye.SOLUTION: There is provided the metal complex dye expressed by the general formula (1)ML1L2. [In the formula, M is a chemical element of 8-10 group on a periodic table, Lis a ligand of a 4,4',4"-trimethoxy-carbonyl-2,2':6',2"-terpyridine and the like, Lis a ligand expressed by following formula (3).(In the formula, Zis an atomic group forming a nitrogen-containing aromatic ring, and Zis an atomic group forming an aromatic ring.)]

Description

  The present invention relates to a dye that efficiently absorbs solar energy and a solar cell using the same.

  Solar cells that can efficiently convert sunlight into electricity are attracting attention from the viewpoint of energy and environmental issues. Solar cells that are put into practical use mainly use silicon, but these solar cells are expensive to manufacture and have a great problem in their future spread. Therefore, research on a new type of solar cell that replaces a silicon-based solar cell has been advanced, and one of them is a dye-sensitized solar cell (Patent Document 1). Dye-sensitized solar cells have advantages such as less resource constraints and relatively low manufacturing costs, and are expected to be widely used. However, it is inferior to silicon-based solar cells in terms of energy conversion efficiency and durability, and improvements in these performances for practical use are being studied.

  In dye-sensitized solar cells, a ruthenium-polypyridine complex is often used as a dye, and it is known that power generation efficiency and durability greatly depend on the dye. Ruthenium-isothiocyanato complexes having a 2,2′-bipyridine derivative or a 2,2 ′: 6 ′, 2 ″ -terpyridine derivative as a ligand are well known as those having particularly high energy conversion efficiency (non-patent literature). 1, and non-patent document 2).

  For practical application of dye-sensitized solar cells, further improvement in conversion efficiency, durability and the like becomes an important research subject. For this purpose, a compound such as a ruthenium complex used as a sensitizing dye is also required to have improved performance and stability to light and heat. In order to improve the energy conversion efficiency, it can be said that it is necessary to develop a sensitizing dye capable of efficiently photoelectrically converting light in a wide range from the visible light region to the infrared light region. In terms of stability, the ruthenium-isothiocyanato complex having the polypyridine ligand mentioned above pointed out the possibility of dissociation or isomerization of the monodentate ligand isothiocyanate by stimulation of heat or light. Yes. These dissociation and isomerization reactions not only reduce the stability of metal complex dyes, but also reduce battery performance. Therefore, the development of metal complex dyes that do not contain monodentate ligands for the purpose of improving stability is necessary.

As such a metal complex dye not containing a monodentate ligand, for example, Non-Patent Documents 3 and 4 report ruthenium complexes represented by the following formulas (4) and (5). This compound is referred to as “compound 1” and “compound 2”. Although the dye-sensitized solar cell incorporating the compounds 1 and 2 has a relatively high conversion efficiency, the region where photoelectric conversion is possible is up to 800 nm, and near infrared light cannot be effectively used. Therefore, even in this type of sensitizing dye, in order to greatly improve the energy conversion efficiency, the region where photoelectric conversion is possible is extended to the long wavelength side, and light in the near infrared region as well as the visible light region is expanded. It is expected to be used effectively.

Japanese Patent No. 2664194

J. Am. Chem. Soc. 1993, 115,6382-6390 J. Am. Chem. Soc. 2001, 123, 1613-1624 J. Am. Chem. Soc. 2009, 131,5930-5934 Angew. Chem. Int. Ed. 2011,50, 2054-2058

  The present invention has been made in view of the above-described situation in the prior art, and its object is to provide a metal complex dye having a novel structure that is sensitive to a wide range of light and excellent in stability, Furthermore, it aims at providing the favorable dye-sensitized oxide semiconductor electrode and dye-sensitized solar cell using this metal complex dye.

［式中、Mは周期律表上の８から１０族の元素であって、L¹は下記一般式（２）で表される配位子であり、L²は下記一般式（３）で表される配位子であり、一般式（２）は、

（式中、A¹〜A³はそれぞれ独立にカルボキシ基、スルホン酸基、リン酸基、若しくはホウ酸基、又はこれらの塩に相当する基であり、R¹〜R³はそれぞれ独立に置換基であり、m1〜m3はそれぞれ独立に0〜3の整数であり（ただしm1〜m3はすべて同時に0になることはない。）、n1〜n3はそれぞれ独立に0〜3の整数である。ただしm1+n1≦4であり、m2+n2≦3であり、m3+n3≦4である。）で表記され、 一般式（３）は、

（式中、Z¹は含窒素芳香環を形成する原子群であり、Z²は芳香環を形成する原子群である。）で表記される。］で表される金属錯体色素である。
また、本発明では、Mをルテニウムとすることができる。
さらに、本発明は、金属錯体色素が酸化物半導体に吸着されてなる色素増感金属酸化物半導体電極である。
さらにまた、本発明は、導電性支持体上に形成された色素増感金属酸化物半導体電極と、その対極、及びそれらの電極に接触するレドックス電解質とを備える色素増感太陽電池である。 The present invention relates to a general formula (1)

[Wherein M is a group 8 to 10 element on the periodic table, L ¹ is a ligand represented by the following general formula (2), and L ² is a general formula (3) A ligand represented by the general formula (2):

(In the formula, A ^{1 to} A ³ are each independently a carboxy group, a sulfonic acid group, a phosphoric acid group, a boric acid group, or a group corresponding to a salt thereof, and R ^{1 to} R ³ are each independently substituted. M1 to m3 are each independently an integer of 0 to 3 (however, m1 to m3 are not all 0 at the same time), and n1 to n3 are each independently an integer of 0 to 3. However, m1 + n1 ≦ 4, m2 + n2 ≦ 3, and m3 + n3 ≦ 4.) General formula (3) is

(Wherein Z ¹ is an atomic group forming a nitrogen-containing aromatic ring, and Z ² is an atomic group forming an aromatic ring). ] The metal complex dye represented by this.
In the present invention, M can be ruthenium.
Furthermore, the present invention is a dye-sensitized metal oxide semiconductor electrode in which a metal complex dye is adsorbed on an oxide semiconductor.
Furthermore, this invention is a dye-sensitized solar cell provided with the dye-sensitized metal oxide semiconductor electrode formed on the electroconductive support body, its counter electrode, and the redox electrolyte which contacts these electrodes.

  According to the metal complex dye of the present invention, the metal complex dye has sensitivity to a wide range of light including near infrared light having a wavelength of up to about 1000 nm, can efficiently extract current, and has excellent stability. Can be obtained. Moreover, the dye-sensitized metal oxide semiconductor electrode and dye-sensitized solar cell using this can achieve favorable conversion efficiency.

［式中、Mは周期律表上の８から１０族の元素であって、L¹は下記一般式（２）で表される配位子であり、L²は下記一般式（３）で表される配位子であり、一般式（２）は、

（式中、A¹〜A³はそれぞれ独立にカルボキシ基、スルホン酸基、リン酸基、若しくはホウ酸基、又はこれらの塩に相当する基であり、R¹〜R³はそれぞれ独立に置換基であり、m1〜m3はそれぞれ独立に0〜3の整数であり（ただしm1〜m3はすべて同時に0になることはない。）、n1〜n3はそれぞれ独立に0〜3の整数である。ただしm1+n1≦4であり、m2+n2≦3であり、m3+n3≦4である。）で表記され、 一般式（３）は、

（式中、Z¹は含窒素芳香環を形成する原子群であり、Z²は芳香環を形成する原子群である。）で表記される。］で表される金属錯体色素であって、種々の錯体となることができる。 The dye of the present invention can be used as a sensitizer for modifying a metal oxide semiconductor of a dye-sensitized solar cell. In the dye-sensitized solar cell of the present invention, a well-known electrode such as a platinum electrode is used as the counter electrode. A well-known redox electrolyte in contact with these electrodes can also be used.
The metal complex dye of the present invention is
General formula (1)

[Wherein M is a group 8 to 10 element on the periodic table, L ¹ is a ligand represented by the following general formula (2), and L ² is a general formula (3) A ligand represented by the general formula (2):

(In the formula, A ^{1 to} A ³ are each independently a carboxy group, a sulfonic acid group, a phosphoric acid group, a boric acid group, or a group corresponding to a salt thereof, and R ^{1 to} R ³ are each independently substituted. M1 to m3 are each independently an integer of 0 to 3 (however, m1 to m3 are not all 0 at the same time), and n1 to n3 are each independently an integer of 0 to 3. However, m1 + n1 ≦ 4, m2 + n2 ≦ 3, and m3 + n3 ≦ 4.) General formula (3) is

(Wherein Z ¹ is an atomic group forming a nitrogen-containing aromatic ring, and Z ² is an atomic group forming an aromatic ring). It is a metal complex pigment | dye represented by this, Comprising: It can become a various complex.

Examples of M in the above formula (1) include iron, cobalt, nickel, ruthenium, osmium, iridium, and platinum. Of these, ruthenium is particularly preferable.
A ¹ , A ² and A ³ in the above formula (2) are each independently a carboxy group, a sulfonic acid group, a phosphoric acid group, a boric acid group, or a group corresponding to a salt thereof. It is preferably a carboxy group or a salt thereof.
When A ¹ , A ² , or A ³ is a salt, the counter cation is ammonium ion, dimethyl ammonium ion, diethyl ammonium ion, tetramethyl ammonium ion, tetraethyl ammonium ion, tetrapropyl ammonium ion, tetrabutyl ammonium ion, sodium An ion, a potassium ion, etc. can be mentioned, Preferably it is a tetrabutyl ammonium ion.
R ¹ , R ² , and R ³ in the above formula (2) are substituents, and the substituent is preferably an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, Acyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyloxy group, acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, alkylthio group, arylthio group, sulfonyl group, halogen atom , A cyano group, a heterocyclic group, and the like.

Specific examples of the structure of L ^{1 in} the present invention include ligands represented by the following formulas (6) to (8).

In the above formula (3), Z ¹ represents an atomic group forming a nitrogen-containing aromatic ring, and the nitrogen-containing aromatic ring formed by Z ¹ is preferably a 4- to 10-membered ring, more preferably a 5- to 6-membered ring. . The nitrogen-containing aromatic ring preferably has 2 to 30 carbon atoms, more preferably 4 to 10 carbon atoms. Z ¹ and Z ² may be bonded to form a condensed ring structure. Examples of the nitrogen-containing aromatic ring formed by Z ¹ include pyridine, pyrazine, pyrimidine, pyridazine, quinoline, isoquinoline, quinoxaline, imidazole, pyrazole, thiazole, isothiazole, oxazole, isoxazole, benzimidazole, benzothiazole, and benzoxazole. , Triazole, oxadiazole, thiadiazole and the like.
The ring formed by Z ¹ may have a substituent, and the substituent is preferably an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an acyl group, an alkoxy group. Carbonyl group, aryloxycarbonyl group, acyloxy group, acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, alkylthio group, arylthio group, sulfonyl group, halogen atom, cyano group, And heterocyclic groups.
Z ² represents an atomic group forming an aromatic ring. The aromatic ring formed by Z ² is preferably a 4-10 membered ring, more preferably a 5-6 membered ring. The aromatic ring formed by Z ² may be either an aromatic hydrocarbon or an aromatic heterocycle, such as benzene, naphthalene, pyridine, pyrazine, pyrimidine, pyridazine, pyrrole, thiophene, furan, imidazole, pyrazole, thiazole, iso Examples include thiazole, oxazole, isoxazole and the like.
Z ² may have a substituent, and examples of the substituent include the groups described above for Z ¹ .

Preferable examples of L ^{2 in} the present invention include, for example, ligands represented by the following formulas (9) to (22).

Specific examples of the dye of the present invention include those represented by the following formulas (23) to (26).

The method for producing a metal complex dye of the present invention includes, for example, reacting 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine (L ³ ) with ruthenium trichloride in advance. Then, a [RuL ³ Cl ₃ ] complex to be a skeleton is synthesized, and L ² is introduced into the complex. The [RuL ³ Cl ₃ ] complex is a known substance and can be synthesized with reference to, for example, J. Am. Chem. Soc. 123 (2001) 1613.

The target metal complex dye is a [RuL ³ Cl ₃ ] complex, L ² , lithium chloride, and triethylamine dissolved in dimethylformamide and pure water, and heated to reflux using a microwave synthesizer. The target metal complex dye can be obtained by cooling the reaction mixture and purifying the solid product from which the solvent has been removed by column chromatography.

The dye-sensitized solar cell of the present invention using the metal complex dye of the present invention comprises a dye-sensitized metal oxide semiconductor electrode formed on a conductive support, an electrolyte, and a counter electrode, which are sequentially laminated. The metal complex dye of the present invention is chemisorbed on the sensitized metal oxide semiconductor electrode.
As the conductive support, a metal or glass or plastic having a conductive layer on the surface can be suitably used. Examples of the conductive layer include metals such as gold, platinum, silver, copper, and indium, conductive carbon, indium tin composite compounds, tin oxide doped with fluorine, and the like. Using these conductive materials, a conductive layer can be formed on the support surface by a conventional method. Further, when the conductive support is a light receiving surface, it is preferably transparent.

  Examples of the material constituting the oxide semiconductor electrode include titanium oxide, niobium oxide, zinc oxide, tin oxide, tungsten oxide, and indium oxide. Of these, titanium oxide, niobium oxide and tin oxide are preferable, and titanium oxide is particularly preferable. There is no limitation on the method of forming the oxide semiconductor electrode. For example, fine particles of oxide to be an oxide semiconductor electrode are formed, suspended in a suitable solvent, and applied onto transparent conductive glass. It can manufacture by the method of heating, after removing.

The method for chemically adsorbing the dye of the present invention to the oxide thin film electrode is not particularly limited, and a known method can be employed. For example, the oxide semiconductor electrode obtained by the above method can be immersed in a solution containing the metal complex dye of the present invention. The solvent used here is not particularly limited as long as it dissolves the metal complex dye, and is preferably methanol, ethanol, butanol, acetonitrile, acetone, diethyl ether, or a mixed solvent in which they are combined. The concentration of the metal complex dye solution is preferably 1 × 10 ^{−4 to} 1 × 10 ⁻² mol / liter. The immersion time can be appropriately adjusted according to the metal complex dye used, the type of solvent, the concentration of the solution, and the like. The immersion time is preferably 0.5 to 50 hours, more preferably 2 to 25 hours. As temperature at the time of immersion, it is preferable that it is 0-100 degreeC, and 10-50 degreeC is still more preferable.

The electrolyte is composed of a conductive material that can transport electrons, holes, and ions. Among the conductive materials, an ionic conductor is preferable, and a solution, solid, or ionic liquid containing a redox system can be used. Specifically, redox systems include I ⁻ / I ₃ ⁻ system, Br ⁻ / Br ₃ ⁻ system, Co ²⁺ / Co ³⁺ system, Fe ²⁺ / Fe ³⁺ system, etc. Nitrile compounds such as acetonitrile, and carbonate compounds such as propylene carbonate. Liquid electrolyte additives include conventionally used nitrogen-containing aromatic compounds such as 4-tert-butylpyridine or imidazole salts such as (1,2-dimethyl-3-propyl) imidazolium iodide. These additives may be added to the liquid electrolyte at a concentration of about 0.1 to 1.5 mol / liter.

  The counter electrode is not particularly limited as long as it has conductivity. For example, a material obtained by depositing platinum on the surface of a conductive support or a material obtained by attaching conductive carbon can be preferably used.

  In order to prevent contact between the dye-sensitized semiconductor electrode and the counter electrode, a spacer may be used. Examples of the spacer include a polymer film such as polyethylene.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1
[RuL ³ Cl ₃ ] complex (200 mg) (L ³ is 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine), 6-phenylpyridine-2-carboxylic acid ( 65 mg), lithium chloride (138 mg), and triethylamine (0.2 mL) are dissolved in dimethylformamide and pure water, and then heated to reflux. The residue after evaporation of the solvent was purified by column chromatography to give 40 mg of product. Analysis by ¹ H-NMR and ESI-MS revealed that this product was represented by the following formula (27). This product is referred to as “Compound 3”.

Example 2
[RuL ³ Cl ₃ ] complex (200 mg) (L ³ is 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine), 6- (4-trifluoromethylphenyl) Pyridine-2-carboxylic acid (87 mg), lithium chloride (138 mg) and triethylamine (0.2 mL) are dissolved in dimethylformamide and pure water, and then heated to reflux. The residue after evaporation of the solvent was purified by column chromatography to give 19 mg of product. Analysis by ¹ H-NMR and ESI-MS revealed that this product was represented by the following formula (28). This product is referred to as “Compound 4”.

Example 3
[RuL ³ Cl ₃ ] complex (200 mg) (L ³ is 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine), 6- (2,4-bistrifluoromethyl Phenyl) pyridine-2-carboxylic acid (110 mg), lithium chloride (138 mg), and triethylamine (0.6 mL) are dissolved in dimethylformamide and pure water, and then heated to reflux. The residue after evaporation of the solvent was purified by column chromatography to give 36 mg of product. Analysis by ¹ H-NMR and ESI-MS revealed that this product was represented by the following formula (29). This product is referred to as “Compound 5”.

Example 4
[RuL ³ Cl ₃ ] complex (200 mg) (L ³ is 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine), 6- (4-fluoro-3-tri Fluoromethylphenyl) pyridine-2-carboxylic acid (93 mg), lithium chloride (138 mg) and triethylamine (0.6 mL) are dissolved in dimethylformamide and pure water, and then heated to reflux. The residue after evaporation of the solvent was purified by column chromatography to give 152 mg of product. Analysis by ¹ H-NMR and ESI-MS revealed that this product was represented by the following formula (30). This product is referred to as “Compound 6”.

Example 5
[RuL ³ Cl ₃ ] complex (200 mg) (L ³ is 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine), 6- (3-fluorobiphenyl) pyridine- 2-Carboxylic acid (95 mg), lithium chloride (138 mg) and triethylamine (0.6 mL) are dissolved in dimethylformamide and pure water, and then heated to reflux. The residue after evaporation of the solvent was purified by column chromatography to give 96 mg of product. Analysis by ¹ H-NMR and ESI-MS revealed that this product was represented by the following formula (31). This product is referred to as “Compound 7”.

Example 6
[RuL ³ Cl ₃ ] complex (100 mg) (L ³ is 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine), 6- (4-acetylphenyl) pyridine- 2-Carboxylic acid (39 mg), lithium chloride (69 mg) and triethylamine (0.3 mL) are dissolved in dimethylformamide and pure water, and then heated to reflux. The residue after evaporation of the solvent was purified by column chromatography to give 115 mg of product. Analysis by ¹ H-NMR and ESI-MS revealed that this product was represented by the following formula (32). This product is referred to as “Compound 8”.

Example 7
[RuL ³ Cl ₃ ] complex (200 mg) (L ³ is 4,4 ′, 4 ″ -trimethoxycarbonyl-2,2 ′: 6 ′, 2 ″ -terpyridine), 6- (5-acetylthiophene-2- Yl) Pyridine-2-carboxylic acid (40 mg), lithium chloride (69 mg) and triethylamine (0.3 mL) are dissolved in dimethylformamide and pure water, and then heated to reflux. The residue after evaporation of the solvent was purified by column chromatography to give 56 mg of product. Analysis by ¹ H-NMR and ESI-MS revealed that this product was represented by the following formula (33). This product is referred to as “Compound 9”.

Example 8
Preparation of dye-sensitized metal oxide semiconductor electrode for photostability evaluation Metal oxide semiconductor electrode is manufactured by Coord. Chem. Rev. 2004, 248,
It was produced according to the method described in 1381-1389. Specifically, a titanium oxide porous film (film thickness: 6 μm, area: 6.25) is formed as a semiconductor layer on the surface of transparent conductive glass in which fluorine oxide doped tin oxide as a transparent conductive support is deposited on the glass surface. What formed cm < ² >) was used.

By immersing the metal oxide semiconductor electrode produced by the above method in a mixed solution of ethanol and dimethylformamide (7: 3 v / v) of the compound obtained above (2 × 10 ⁻⁴ mol / liter) for 22 hours, dye enhancement A metal oxide semiconductor electrode was formed. The light stability of the ruthenium complex dye was evaluated by performing a 6-hour light irradiation test using a solar simulator (AM1.5, 100 mWcm ^-2 ) and an ultraviolet cut filter. In Table 1 below, A indicates that the absorption spectrum did not change before and after the light irradiation, B indicates that the absorption maximum shift on the longest wavelength side was observed, and C indicates that the absorption spectrum was changed in shape. In this evaluation rank, D is a shift of the absorption maximum on the longest wavelength side and a change in spectral shape.

Example 9
Preparation of dye-sensitized solar cell A metal oxide semiconductor electrode is formed on the surface of transparent conductive glass in which tin oxide doped with fluorine, which is a transparent conductive support, is deposited on the glass surface according to the same method as described above. A layer in which a porous titanium oxide film (thickness of 31 μm, area of 0.25 cm ² ) was used as a layer was used.

By immersing the metal oxide semiconductor electrode produced by the above method in a mixed solution of ethanol and dimethylformamide (7: 3 v / v) of the compound obtained above (2 × 10 ⁻⁴ mol / liter) for 22 hours, dye enhancement A metal oxide semiconductor electrode was formed. A polyethylene film spacer and an electrolyte solution were sandwiched between the semiconductor electrode and a counter electrode obtained by depositing platinum on the surface of the conductive glass to obtain a dye-sensitized solar cell. Electrolyte solutions include lithium iodide (0.1 mol / liter), iodine (0.05 mol / liter), (1,2-dimethyl-3-propyl) imidazolium iodide (0.6 mol / liter), 4-tert-butyl An acetonitrile solution containing pyridine (0.1 mol / liter) was used. Solar cell performance was evaluated using a solar simulator (AM1.5, 100 mWcm ^-2 ).

  Using the compounds shown in Table 1 as sensitizing dyes, the short-circuit current density (Jsc), open-circuit voltage (Voc), fill factor (ff), and photoelectric conversion efficiency (η) were measured using the battery prepared by the above method. . The obtained results are shown in Table 1. In Table 1, as a comparative example, the results of the same evaluation for the N719 dye and the black dye, which are ruthenium complex dyes reported in Non-Patent Document 1 and Non-Patent Document 2, are also shown. For N719 dye and black dye, lithium iodide (0.1 mol / liter), iodine (0.05 mol / liter), (1,2-dimethyl-3- A solution of acetonitrile containing propyl) imidazolium iodide (0.6 mol / liter) and 4-tert-butylpyridine (0.5 mol / liter) was used.

  As can be seen from Table 1, the compounds of the present invention showed excellent light stability. It was also found that when the compound of the present invention is used as a sensitizing dye, not only visible light but also near infrared light having a wavelength of up to about 1000 nm can be used in any case.

  According to the present invention, it is possible to use solar energy not only in the visible light region but also in a wide wavelength region up to the near-infrared region, and by using a pigment having excellent stability, the pigment has both high conversion efficiency and durability. A sensitized solar cell can be provided.

Claims (4)

General formula (1)

[Wherein M is a group 8 to 10 element on the periodic table, L ¹ is a ligand represented by the following general formula (2), and L ² is a general formula (3) A ligand represented by the general formula (2):

(In the formula, A ^{1 to} A ³ are each independently a carboxy group, a sulfonic acid group, a phosphoric acid group, a boric acid group, or a group corresponding to a salt thereof, and R ^{1 to} R ³ are each independently substituted. M1 to m3 are each independently an integer of 0 to 3 (however, m1 to m3 are not all 0 at the same time), and n1 to n3 are each independently an integer of 0 to 3. However, m1 + n1 ≦ 4, m2 + n2 ≦ 3, and m3 + n3 ≦ 4.) General formula (3) is

(Wherein Z ¹ is an atomic group forming a nitrogen-containing aromatic ring, and Z ² is an atomic group forming an aromatic ring). ] The metal complex dye represented by this.   The metal complex dye according to claim 1, wherein M is ruthenium.   A dye-sensitized metal oxide semiconductor electrode, wherein the metal complex dye according to claim 1 or 2 is adsorbed on an oxide semiconductor.   A dye-sensitized solar cell comprising: the dye-sensitized metal oxide semiconductor electrode according to claim 3 formed on a conductive support; a counter electrode; and a redox electrolyte in contact with the electrode.