KR101264083B1 - Novel asymmetric quinacridone photosensitizer for photovoltaic cell and photovoltaic cell including same - Google Patents

Abstract

The present invention relates to a quinacridone dye for a dye-sensitized solar cell having a novel asymmetric structure. The dye according to the present invention has a high absorption of light and an absorption region between 400 to 550 nm of the largest intensity of sunlight. At the same time, it has excellent heat resistance and light resistance, and can be applied as a dye-sensitizer for dye-sensitized solar cells, thereby greatly improving the photoelectric conversion efficiency and durability of the solar cell.

Description

Novel asymmetric quinacridone dyes and dye-sensitized solar cells using the same {NOVEL ASYMMETRIC QUINACRIDONE PHOTOSENSITIZER FOR PHOTOVOLTAIC CELL AND PHOTOVOLTAIC CELL INCLUDING SAME}

The present invention relates to a dye used in a dye-sensitized solar cell and a dye-sensitized solar cell using the same, and more particularly, to prepare an asymmetric quinacridone dye having high molar extinction coefficient and excellent heat resistance and light resistance, and a light absorbing layer for solar cell The present invention relates to a dye that can be applied to improve photoelectric conversion efficiency and at the same time improve durability.

Recently, various studies have been conducted to replace existing fossil fuels in order to reduce the emission of carbon dioxide which is the main cause of global warming and to solve the energy problem. Extensive research to harness natural energy such as wind, nuclear power, and solar power has been conducted to replace petroleum resources that will be exhausted in the near future. Among these, solar cells using solar energy are the most environmentally friendly, Unlike other energy sources, resources can be infinite if we only develop appropriate methods of use. In addition, it is attracting attention as an alternative renewable energy because self-generation is possible as an energy source of information and communication devices. Since solar cells using selenium (Se) were developed in 1983, silicon solar cells have been in the spotlight in recent years, but they are limited in practical use because they are very expensive in terms of manufacturing cost, and battery efficiency is still quite insufficient. To overcome this problem, the development of low-cost dye-sensitized solar cells has been progressed by various groups.

Dye-sensitized solar cells absorb the visible energy of light and produce electron-hole pairs.The photoelectrochemical system consists mainly of photosensitive dye molecules and transition metal oxides that transfer the generated electrons. It is a solar cell. A dye-sensitized solar cell using nanoparticle titanium oxide, developed in 1991 by Michael Gratzel of the Swiss National Institute of Advanced Technology (EPFL), is a representative example of conventional dye-sensitized solar cells.

The dye-sensitized solar cell developed by them has the advantage that it can be applied to building exterior wall glass windows or glass greenhouses due to the transparent electrode, and it is cheaper to manufacture than the conventional silicon solar cell, but the photoelectric conversion efficiency is low, so the practical application is limited. have.

Photoelectric conversion efficiency is proportional to the amount of electrons generated by the absorption of sunlight. In order to increase the efficiency of solar cells, it is possible to increase the absorption of sunlight or increase the amount of dye adsorbed in order to generate more electrons or to prevent the generated exciton from being dissipated by electron-hole recombination. Can also give In order to increase the absorption of sunlight, it is possible to increase the reflectance of the platinum electrode or to manufacture the particles of the oxide semiconductor to nanometer size to increase the adsorption amount of the dye per unit area. Methods have been developed. However, such a conventional method has a limitation in improving the photoelectric conversion efficiency of the solar cell, and thus, there is an urgent need for the development of a new technology for improving the efficiency, in particular, the development of a new dye having high photoelectric conversion efficiency.

An object of the present invention is to provide a dye-sensitized solar cell dye having a high light absorption and excellent heat resistance and light resistance, to provide a dye-sensitized solar cell having improved photoelectric conversion efficiency and durability including the dye.

In order to solve the above problems, according to a preferred embodiment of the present invention, there is provided a dye for a solar cell dye comprising a compound having a structure of formula (1).

[Formula 1]

In Formula 1, B is a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic group, a vinyl group, or a substituted or unsubstituted polyvinyl group, R is a substituted or unsubstituted aliphatic hydrocarbon Group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic group, and A is an acidic functional group.

According to another suitable embodiment of the present invention, B is a vinyl group, polyvinyl group, benzene, naphthalene, anthracene, fluorene, biphenyl, furan, pyrrole, thiophene, carbazole, thiazole, oxazole, oxazine And it provides a dye for a dye-sensitized solar cell, characterized in that one selected from the group consisting of.

According to another suitable embodiment of the present invention, B is a dye-sensitized embodiment comprising a substituent selected from the group consisting of alkyl, alkoxy, aryl group, alkenyl group, arylene group, alkylene group, amino group and combinations thereof A battery dye is provided.

According to another suitable embodiment of the present invention, R is hydrogen, substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group having 6 to 20 carbon atoms, substituted or unsubstituted aromatic It provides a dye-sensitized solar cell dye, characterized in that selected from the group consisting of a heterocyclic group and combinations thereof.

According to another suitable embodiment of the present invention, A is selected from the group consisting of a carboxyl group, phosphorous acid group, sulfonic acid group, phosphinic acid group, hydroxy group, oxycarboxylic acid, acidamide and combinations thereof A battery dye is provided.

According to another suitable embodiment of the present invention, the dye provides a dye for a solar cell dye characterized in that it comprises a compound selected from the group consisting of a compound having a structure of formula 2 to 4 and combinations thereof.

 [Formula 2]

(3)

[Formula 4]

According to another suitable embodiment of the present invention, there is provided a dye-sensitized solar cell device using the dye.

Dye-sensitized solar cell dye of the present invention has a high molar extinction coefficient and at the same time excellent heat resistance and light resistance, can be applied to the light absorbing layer for solar cells to increase the photoelectric conversion efficiency and durability.

1 is a schematic view showing a dye-sensitized solar cell according to an embodiment of the present invention.
2 is an ultraviolet-visible light absorption wavelength according to the dye of Example 1. FIG.
3 is an IPCE curve of the dye-sensitized solar cell prepared in Example 2. FIG.

Hereinafter, the present invention will be described in more detail.

The first step in driving a solar cell in a dye-sensitized solar cell is the process of generating a photo charge from solar energy. Typically, a dye material is used for generating a photo charge, and the dye material is excited by absorbing light transmitted through the conductive transparent substrate.

As the dye material, metal complexes are widely used, and mono, bis, or tris (substituted 2,2′-bipyridine) complex salts of ruthenium are generally used among the metal complexes. However, they had a problem that the efficiency of the electrons excited by light in the ground state of the metal complex falls back to the ground state is relatively high, which is low efficiency. In order to solve this problem, there have been many reports of introducing various electron transfer materials to metal complexes through covalent bonds. However, the introduction of electron transfer materials through covalent bonds has a problem that the process is very complicated and difficult to introduce various electron transfer materials.

In order to solve the above problems, the present invention can improve the photoelectric conversion efficiency of dye-sensitized solar cells by preparing and using a dye of a compound in which a variety of electron donor groups and bridge groups are introduced asymmetrically in the quinacridone structure. have.

More specifically, the dye-sensitized solar cell dye of the present invention includes a compound having a structure of formula (1).

[Formula 1]

In Formula 1, B is selected from a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted hetero ring group, a vinyl group, a substituted or unsubstituted polyvinyl group. R is a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic group, and A is an acidic functional group.

In Formula 1, B is independently a vinyl group, a polyvinyl group, benzene, naphthalene, anthracene, fluorene, biphenyl, furan, pyrrole, thiophene, carbazole, thiazole, oxazole, oxazine and these It is preferably selected from the group consisting of

In addition, the C and B may include a substituent consisting of alkyl, alkoxy, aryl group, alkenyl group, arylene group, alkylene group, amino group and combinations thereof. The substituent is the same as described above in D.

In Formula 1, R is hydrogen, substituted or unsubstituted aliphatic hydrocarbon group of 1 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group of 6 to 20 carbon atoms, substituted or unsubstituted aromatic heterocyclic group and their It is preferably selected from the group consisting of combinations.

In Formula 1, A is an acidic functional group, preferably selected from a substituent consisting of a carboxyl group, a phosphorous acid group, a sulfonic acid group, a phosphinic acid group, a hydroxy group, an oxycarboxylic acid, an acid amide, and a combination thereof, and more preferably a carboxyl group. to be.

Most preferably, the dye may include a compound having a structure of any one of Formulas 2 to 4 and a combination thereof.

[Formula 2]

(3)

[Formula 4]

1 is a cross-sectional view schematically showing the structure of a dye-sensitized solar cell according to an embodiment of the present invention.

Referring to FIG. 1, the dye-sensitized solar cell 10 has a sandwich structure in which two plate electrodes (working electrode 11 and counter electrode 14) are surface-bonded to each other. The light absorbing layer 12 is formed on one surface of the transparent electrode facing the relative electrode 14, and the light absorbing layer 12 is adsorbed by the semiconductor fine particles and the semiconductor fine particles to form electrons with visible light absorption. Photosensitive dyes are excited. In addition, the space between the two electrodes is filled with the redox electrolyte 13.

Therefore, when sunlight enters into the dye-sensitized solar cell 10, the photons are first absorbed by the dye molecules in the light absorbing layer 12. Accordingly, the dye molecules are electron-transferred from the ground state to the excited state to form electron-hole pairs. The electrons in the state are injected into the conduction band of the metal oxide particle interface, and the injected electrons are transferred to the working electrode 11 through the interface and move to the state electrode 14, which is the counter electrode, through an external circuit. . On the other hand, the dye oxidized as a result of the electron transfer is reduced by the ions of the redox couple in the electrolyte 13, and the oxidized ions reach the interface of the second electrode 14 to achieve charge neutrality. The fuel-sensitized solar cell 10 operates by reducing with electrons.

The working electrode 11 includes a transparent substrate and a conductive layer formed on the transparent substrate.

The transparent substrate is not particularly limited as long as it is a material having transparency to allow incidence of external light. Therefore, the transparent substrate may be made of glass or plastic. Examples of the plastic include polyethylene terephtalate (PET), polyethylene napthalate (PEN), polycarbonate (PC), polypropylene (PP), polyimide (PI), and triacetyl. It may be used as cellulose (triacetyl cellulose, TAC) or a copolymer thereof.

The transparent substrate may be doped with a material selected from the group consisting of Ti, In, Ga, and Al.

A conductive layer is positioned on the transparent substrate. The conductive layer is fluorine tin oxide (FTO), indium tin oxide (ITO), ZnO- (Ga ₂ O ₃ or Al ₂ O ₃ ), tin oxide, antimony tin oxide (antimony tin oxide) oxide, ATO), zinc oxide (zinc oxide) and a conductive metal compound selected from the group consisting of a mixture thereof may be used, more preferably florin tin oxide may be used.

The semiconductor fine particles may be a compound having a compound semiconductor or a perovskite structure in addition to a semiconductor represented by silicon.

The semiconductor is preferably an n-type semiconductor in which conduction band electrons become carriers to provide an anode current under optical excitation, and the compound semiconductor is Ti, Zr, Sr, Zn, In, Yr, La, V, Mo, W Oxides of metals selected from the group consisting of Sn, Nb, Mg, Al, Y, Sc, Sm, Ga, In and TiSr can be used. Preferably, TiO ₂ , SnO ₂ , ZnO, WO ₃ , Nb ₂ O ₅ , TiSrO ₃ or a mixture thereof may be used, and more preferably TiO ₂ may be used. The kind of the semiconductor is not limited to these.

In addition, the semiconductor fine particles preferably have a large surface area in order for the dye adsorbed on the surface to absorb more light. Therefore, the semiconductor fine particles preferably have an average particle diameter of 50 nm or less, and more preferably, may have an average particle diameter of 15 to 20 nm. When the particle diameter exceeds 50 nm, the surface area becomes small, which may lower the catalyst efficiency.

A dye for absorbing external light and generating excitation electrons is adsorbed on the surface of the semiconductor fine particles. The dye is the same as described above.

The light absorbing layer 12 having the above configuration is preferably 8 to 20 micrometers thick, more preferably 12 to 16 micrometers thick.

The counter electrode 14 is positioned to face the working electrode 11 on which the light absorption layer 12 is formed. The counter electrode 14 includes a transparent substrate and a transparent electrode and a catalyst electrode (not shown) formed on the transparent substrate so as to face the working electrode 11.

The transparent substrate may be made of glass or plastic as in the working electrode. Examples of the plastic include polyethylene terephtalate (PET), polyethylene napthalate (PEN), polycarbonate (PC), polypropylene (PP), polyimide (PI), and triacetyl. Cellulose (triacetyl cellulose, TAC) or copolymers thereof may be used.

A transparent electrode is formed on the transparent substrate, and the transparent electrode is made of fluorine tin oxide (FTO), indium tin oxide (ITO), ZnO- (Ga ₂ O ₃ or Al ₂ O ₃ ), A conductive metal compound selected from the group consisting of tin oxide, antimony tin oxide (ATO), zinc oxide, and mixtures thereof may be used, and more preferably florine tin oxide may be used. .

In addition, every electrode is formed on the transparent electrode. The catalyst electrode serves to activate a redox couple, platinum (Pt), gold (Au), ruthenium (Ru), palladium (Pd), rhodium (Rh), iridium (Ir), Osmium (Os), WO ₃ , TiO ₂ And conductive materials such as conductive polymers.

In addition, the catalytic electrode side facing the working electrode for the purpose of improving the catalytic effect of redox is preferable to have a microstructure to increase the surface area. For example, Pt or Au may be in a black state, and carbon may be in a porous state.

The counter electrode 14 includes a hole (not shown) penetrating the counter electrode to inject the electrolyte.

The electrolyte layer is composed of an electrolyte solution, and the electrolyte solution serves to transfer dye by receiving electrons from a counter electrode by oxidation and reduction, wherein the voltage of the open circuit is determined by the energy level of the dye and oxidation and reduction levels of the electrolyte. It is determined by the difference.

As the electrolyte solution, for example, a solution in which iodine is dissolved in acetonitrile can be used, but is not necessarily limited thereto.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited or limited by the following Examples.

Example  1: Preparation of Dye Having Structure of Chemical Formula 2

Compound 1 having the structure of Chemical Formula 2 was prepared by following the steps shown in Scheme 1 below.

[Reaction Scheme 1]

[Formula 2]

(1) Synthesis of Intermediate Compound (1)

In a 250 ml round bottom flask, 1.56 g (0.005 mol) of quinacridone (TCI, Q0057), 1.822 g (0.005 mol) of hexadecyltriammonium bromide and 160 ml of toluene were added and the stomach mixture was stirred. 50 g of 50% aqueous KOH solution is added to the solution. The mixture was heated to reflux to 95 ° C., and when the mixture was completely dissolved, 2.16 ml (0.02 mol) of 1-bromobutane was added and refluxed at 95 ° C. for 12 hours. After the reaction is completed, the reaction mixture is cooled to room temperature, neutralized with 10% aqueous HCl solution, and extracted by adding 500 ml of chloroform. After washing with water and saturated brine, water was removed by passing through MgSO ₄ , and chloroform was removed using a rotary distillation apparatus, and then dried in an oven at 80 ° C. for one day. When drying was completed, column purification was performed using methylene chloride as a developing solution, and 1.7 g of red powder was obtained. (Yield 80%)

¹ H NMR (500 MHz, CDCl ₃ ) δ (ppm) 8.78 (s, 2H), 8.58 (d, 2H), 7.77 (t, 2H), 7.52 (d, 2H), 7.28 (t, 2H), 4.52 ( t, 4H), 2.01 (m, 4H), 1.67 (m, 4H), 1.12 (m, 6H). FAB MS (m / z): 425 [M < + >].

(2) Synthesis of Intermediate Compound (2)

Into a 50 ml round bottom flask, 1.68 g (0.0035 mol) of intermediate compound (1), 1.77 g (0.0045 mol) of benzyltrimethylammonium tribromide and 80 ml of ethanol were added thereto and stirred. The mixture is stirred at room temperature for 24 hours, then heated to 85 ° C. and refluxed for 16 hours. After the reaction is completed, 100 ml of chloroform is added, the solvent is removed using a rotary distillation apparatus, and then dried in an oven at 80 ° C. for one day. When drying was completed, column purification was carried out using methylene chloride as a developing solution, and 0.88 g of red powder was obtained. (Yield: 51%)

¹ H NMR (500 MHz, CDCl ₃ ) δ (ppm) 8.67 (s, 1H), 8.63 (s, 1H), 8.57 (s, 1H), 8.49 (d, 1H), 7.73-7.71 (m, 2H), 7.46 (d, 1H), 7.34 (d, 1H), 7.22 (m, 1H), 4.46 (m, 4H) 1.97-1.93 (m, 4H), 1.3-1.11 (m, 6H). FAB MS (m / z): 503 [M < + >].

(3) Synthesis of Intermediate Compound (3)

Intermediate compounds in 100ml round bottom flask (2) 0.76 g (0.0015mol) , Pd (PPh 3) 4 0.086 g (0.0000753mol), 5- formyl-2-thiophene-boronic acid (5-formyl-2-thiophene boronic acid) 0.26 g (0.00166 mol), 52 ml of toluene, 22 ml of ethanol and 2.9 ml of 2M K ₂ CO ₃ were added thereto, the temperature was raised to 110 ° C. while stirring, and the mixture was refluxed for 12 hours. When the reaction is complete, the reaction is cooled to room temperature and the solvent is removed using a rotary distillation apparatus. Then, extract with 150ml of chloroform and water, wash with water and saturated brine and remove water by passing through MgSO ₄ . And chloroform is removed using a rotary distillation apparatus and dried for one day in an 80 ℃ oven. After drying, the column was purified by using methylene chloride as a developing solution to obtain 0.28 g of red powder. (Yield: 35%)

¹ H NMR (500 MHz, CDCl ₃ ) δ (ppm) 9.92 (s, 1H), 8.91 (s, 1H), 8.83 (d, 2H), 8.61 (d, 1H), 8.06 (d, 1H), 7.80 ( d, 2H), 7.70 (t, 1H), 7.62 (d, 1H), 7.55 (d, 1H), 7.32 (m, 1H), 4.57 (m, 4H), 2.03 (m, 4H), 1.68 (m , 4H), 1.14 (m, 6H). FAB MS (m / z): 535 [M < + >].

(4) Synthesis of Compound 1 Having a Structure of Formula 2

0.27 g (0.0005 mol) of the intermediate compound (3) was added to a 250 ml round bottom flask, and 150 ml of acetonitrile was added to dissolve it, and then 0.11 g (0.00125 mol, 2.5 equivalents) of cyanoacetic acid under nitrogen gas. And piperidine 0.15ml (0.0015mol, 3 equiv) were added and stirred. The mixture was heated up to 92 ° C. and refluxed for 6 hours. After the reaction is completed, the reaction mixture is cooled to room temperature, and then the solvent is removed using a rotary distillation apparatus and dried in an oven at 80 ° C. for one day. When drying was completed, column purification was performed using chloroform: methanol = 1: 5 as a developing solution to obtain 0.162 g of a red powder. (Yield: 54%)

1 H NMR (500 MHz, CDCl 3) δ (ppm) 8.96 (s, 1H), 8.91 (d, 2H), 8.83 (d, 1H), 8.21 (d, 1H), 7.95 (d, 2H), 7.82 (t, 1H), 7.67 (d, 1H), 7.58 (d, 1H), 7.33 (m, 1H), 7.25 (s, 1H), 4.55 (m, 4H), 2.01 (m, 4H), 1.67 (m, 4H ), 1.13 (m, 6 H). FAB MS (m / z): 602 [M < + >].

Example   2: Preparation of Dye Having Structure of Formula 3

Compound 2 having a structure of Chemical Formula 3 was prepared by following the steps shown in Scheme 2.

[Reaction Scheme 2]

(3)

(1) Synthesis of Intermediate Compound (1)

Intermediate compound (1) was prepared in the same manner as the intermediate compound (1) of Example 1.

(2) Synthesis of Intermediate Compound (2)

Intermediate compound (1) was prepared in the same manner as the intermediate compound (2) of Example 1.

(3) Synthesis of Intermediate Compound (4)

0.76 g (0.0015 mol) of intermediate compound (2) in a 100 ml round bottom flask, 0.086 g (0.0000753 mol) of Pd (PPh ₃ ) ₄ , 0.25 g (0.00166 mol) of 4-formylphenyl boronic acid , 52 ml of toluene, 22 ml of ethanol and 2.9 ml of 2M K ₂ CO ₃ were added thereto, the temperature was raised to 110 ° C. while stirring, and the mixture was refluxed for 12 hours. When the reaction is complete, the reaction is cooled to room temperature and the solvent is removed using a rotary distillation apparatus. Then, extract with 150ml of chloroform and water, wash with water and saturated brine and remove water by passing through MgSO ₄ . And chloroform is removed using a rotary distillation apparatus and dried for one day in an 80 ℃ oven. When drying was completed, column purification was performed using methylene chloride as a developing solution, and 0.35 g of red powder was obtained. (Yield 45%)

¹ H NMR (500 MHz, CDCl ₃ ) δ (ppm) 10.08 (s, 1H), 8.87 (s, 1H), 8.79 (d, 2H), 8.57 (d, 1H), 8.05 (d, 1H), 8.01 ( d, 2H), 7.90 (d, 2H), 7.75 (t, 1H), 7.64 (d, 1H), 7.53 (d, 1H), 7.29 (m, 1H), 4.57 (m, 4H), 2.03 (m , 4H), 1.68 (m, 4H), 1.14 (m, 6H). FAB MS (m / z): 529 [M < + >].

(2) Synthesis of Compound 2 Having a Structure of Formula 3

0.26 g (0.0005 mol) of the intermediate compound (4) was added to a 250 ml round bottom flask, and 150 ml of acetonitrile was added to dissolve it, and then 0.11 g (0.00125 mol, 2.5 equivalents) of cyanoacetic acid under nitrogen gas. And piperidine 0.15ml (0.0015mol, 3 equiv) were added and stirred. The mixture was heated up to 92 ° C. and refluxed for 6 hours. After the reaction is completed, the reaction mixture is cooled to room temperature, and then the solvent is removed using a rotary distillation apparatus and dried in an oven at 80 ° C. for one day. When drying was completed, column purification was performed using chloroform: methanol = 1: 5 as a developing solution to obtain 0.19 g of a red powder. (Yield: 65%)

1 H NMR (500 MHz, CDCl 3) δ (ppm) 8.65 (s, 2H), 8.64 (d, 1H), 8.35 (d, 1H), 8.23 (d, 1H), 8.01 (d, 2H), 7.97 (d, 1H), 7.96 (t, 1H), 7.90 (d, 2H), 7.84 (d, 2H), 7.30 (s, 1H), 4.59 (m, 4H), 1.89 (m, 4H), 1.62 (m, 4H ), 1.08 (m, 6 H). FAB MS (m / z): 596 [M < + >].

Example   3: Preparation of Dye Having Structure of Formula 4

Compound 3 having a structure of Chemical Formula 4 was prepared by following the steps shown in Scheme 3 below.

Scheme 3

[Formula 4]

(1) Synthesis of Intermediate Compound (1)

Intermediate compound (1) was prepared in the same manner as the intermediate compound (1) of Example 1.

(2) Synthesis of Intermediate Compound (2)

Intermediate compound (1) was prepared in the same manner as the intermediate compound (2) of Example 1.

(3) Synthesis of Intermediate Compound (5)

Intermediate compound (2) 0.76 g (0.0015mol) , Pd (PPh 3) 4 0.086 g (0.0000753mol), 4- formyl-2-furan in 100ml round bottom flask boronic acid (5-Formyl-2-furanboronic acid) 0.23 g (0.00166 mol), 52 ml of toluene, 22 ml of ethanol and 2.9 ml of 2M K ₂ CO ₃ were added thereto, the temperature was raised to 110 ° C. under stirring, and the mixture was refluxed for 12 hours. When the reaction is complete, the reaction is cooled to room temperature and the solvent is removed using a rotary distillation apparatus. Then, extract with 150ml of chloroform and water, wash with water and saturated brine and remove water by passing through MgSO ₄ . And chloroform is removed using a rotary distillation apparatus and dried for one day in an 80 ℃ oven. When drying was completed, column purification was performed using methylene chloride as a developing solution, and 0.39 g of red powder was obtained. (Yield 50%)

¹ H NMR (500 MHz, CDCl ₃ ) δ (ppm) 9.94 (s, 1H), 8.92 (s, 1H), 8.81 (d, 2H), 8.64 (d, 1H), 8.02 (d, 1H), 7.82 ( d, 2H), 7.71 (t, 1H), 7.61 (d, 1H), 7.54 (d, 1H), 7.33 (m, 1H), 4.56 (m, 4H), 2.02 (m, 4H), 1.68 (m , 4H), 1.14 (m, 6H). FAB MS (m / z): 518 [M < + >].

(2) Synthesis of Compound 3 Having Structure of Formula 4

0.26 g (0.0005 mol) of the intermediate compound (5) was added to a 250 ml round bottom flask, and 150 ml of acetonitrile was added to dissolve it, and then 0.11 g (0.00125 mol, 2.5 equivalents) of cyanoacetic acid under nitrogen gas. And piperidine 0.15ml (0.0015mol, 3 equiv) were added and stirred. The mixture was heated up to 92 ° C. and refluxed for 6 hours. After the reaction is completed, the reaction mixture is cooled to room temperature, and then the solvent is removed using a rotary distillation apparatus and dried in an oven at 80 ° C. for one day. When drying was completed, column purification was performed using chloroform: methanol = 1: 5 as a developing solution, to obtain 0.16 g of a red powder. (Yield: 56%)

1 H NMR (500 MHz, CDCl 3) δ (ppm) 8.64 (s, 2H), 8.62 (d, 1H), 8.31 (d, 1H), 8.22 (d, 1H), 8.01 (d, 2H), 7.95 (d, 1H), 7.93 (t, 1H), 7.90 (d, 2H), 7.81 (d, 2H), 7.28 (s, 1H), 4.57 (m, 4H), 1.88 (m, 4H), 1.62 (m, 4H ), 1.08 (m, 6 H). FAB MS (m / z): 585 [M < + >].

Example  4: Manufacture of Dye-Sensitized Solar Cell

(1) working electrode fabrication

Cut the FTO substrate (Fluorine-doped tin oxide coated conduction glass, Pilkington, TEC-8) into 1.5cm x 1.5cm size, rub it by hand while washing with acetone to remove impurities such as organic matter on the surface. Deposit twice a minute. Thereafter, the ultrasonic washing is repeated twice for 10 minutes using ethanol. After that, it is rinsed thoroughly with anhydrous ethanol and dried in an oven. In order to improve the contact force with TiO ₂ on the thus prepared FTO substrate, 0.2M titanium butoxide (Titanium (IV) butoxide) solution was coated by spin coating, and the solvent was completely dried in an oven.

After that, TiO ₂ (230 (M2331) -2T) was coated on the FTO substrate by the doctor blade technique, dried in an oven at 100 ° C. for 10 minutes, and then heated to 500 ° C. for 30 minutes to sinter for 9 to 10 minutes. A micrometer thick TiO ₂ transparent layer is obtained. TiO ₂ (CCIC-1T) is coated and sintered thereon in the same manner to obtain a TiO ₂ scattering layer having a thickness of 4 to 5 micrometers.

TiO ₂ thus obtained The film was immersed in a 0.5mM chloroform solution made using the dye synthesized in Example 1 for 40 hours to adsorb the dye onto the TiO ₂ surface. (The solvent used to make the dye solution is a solvent that can dissolve the dye well.) After the adsorption is completed, completely wash the dye that has not been adsorbed with the solvent. Scrape off the adsorbed film leaving only 6.5mm x 6.5mm.

(2) counter electrode fabrication

Using a diamond drill, drill two holes for the electrolyte injection into a 1.5 cm-1.5 cm FTO substrate. Thereafter, it is washed and dried in the same manner as the washing method described above. Then, soak for 20 minutes in 0.7mM hydrogen hexachloroplatinate (H ₂ PtCl ₆ ) 2-propanol solution, take out and heat-treated in an oven at 400 ℃ for 30 minutes.

(3) Sandwich cell production

Between the working electrode and the counter electrode, Sullyn (Surlyn, Dupont 1702) was cut into rectangular bands, and the two electrodes were attached to each other using a hot press. Then, the electrolyte was injected through the two small holes. After that, a sandwich cell is produced by sealing with Surlyn strip and cover glass. The electrolyte solution was 0.2 M LiI, 0.005 M I ₂ , 0.5 M 1-methyl-3-propylimidazolium iodide and 0.5 M 4-tert-butyl Pyridine (4-tert-butylpyridine) was prepared by dissolving acetonite in acetonitrile solvent.

(4) Photocurrent-voltage and Incident Photon to Current Efficiency

When irradiated with a Xe lamp (300W Xe arc lamp) equipped with a solar simulating filter of AM 1.5 to the solar cell manufactured above, the current-voltage curve was generated using a Keithly model 2400 source measuring unit. Got it. In addition, IPCE was measured at a rate of 10 Hz in a 300-800 nm wavelength region using a monochromic beam of a 75 W Xe lamp, and a calibration was performed using a silicon photodiode (NIST-calibrated photodiode G425).

The results of testing the performance of the solar cell thus produced are shown in Table 1 below.

Example 5 Fabrication of Dye-Sensitized Solar Cell

A dye-sensitized solar cell was manufactured in the same manner as in Example 4, except that the compound prepared in Example 2 was used as a dye.

The results of testing the performance of the solar cell thus produced are shown in Table 1 below.

Example 6: Preparation of Dye-Sensitized Solar Cell

A dye-sensitized solar cell was manufactured in the same manner as in Example 4, except that the compound prepared in Example 3 was used as a dye.

The results of testing the performance of the solar cell thus produced are shown in Table 1 below.

Absorption
λ _abs / nm
(ε / M ^-1 cm ^-1 ) Emission
λ _em / nm Photovoltaic performance data ^c J _sc
/ mAcm ^-2 V _oc
/ mV FF η (%) Example 4 414 (45,200)
538 (15,100) 571 8.29 685.1 0.640 3.63 Example 5 384 (38,500)
536 (12,600) 563 6.14 660.5 0.645 2.62 Example 6 411 (42,300)
537 (14,500) 568 8.45 684.2 0.652 3.89

As a result of testing the performance of the solar cells prepared in Examples 4 to 6, the short circuit current (J _sc ) is 8.29 mAcm ^-2 , 6.14 mAcm ^-2 and 8.45 mAcm ^-2 , respectively, and the open voltage (V _oc ) is 685.1 mV, 660.5 mV and 684.2 mV, the filling factor (FF) had values of 0.640, 0.645 and 0.652, respectively, and the photoelectric conversion efficiencies (η) were 3.63%, 2.62% and 3.89%, respectively. Figure 2 shows the absorption wavelength of the ultraviolet-visible photoelectric region of Compound 1 prepared in Example 1, the molar extinction coefficient is 40,000 dm ³ mol ^-1 cm ^-1 or more at 414 nm, 15,000 dm ³ mol ^- at 538 nm ¹ cm ⁻¹ or more, it has a significantly higher value than conventional metal complexes. The molar extinction coefficient is an important variable in improving the photoelectric conversion efficiency of the solar cell. 3 shows an IPCE curve of a solar cell manufactured using Compound 1, and has a high conversion efficiency of 61.74% in the 430 nm wavelength region.

Claims (9)

Dye-sensitized solar cell dye comprising a compound having a structure of formula (1).
[Formula 1]

(In Formula 1, A is a carboxy group, B is any one selected from aromatic heterocyclic groups of phenyl, thiazole, furan, pyrrole, R is any one of alkyl groups having 1 to 10 carbon atoms) delete delete delete delete The dye-sensitized solar cell dye according to claim 1, wherein the dye is a compound having a structure of Formula 2 below.
(2)

The dye-sensitized solar cell dye according to claim 1, wherein the dye is a compound having a structure of Formula 3 below.
(3)

The dye-sensitized solar cell dye of claim 1, wherein the dye is a compound having a structure represented by the following Chemical Formula 4.
[Chemical Formula 4]

Dye-sensitized solar cell device using the dye of claim 1.

Images