TWI565700B - Perylene-3,4-dicarboxylic anhydride skeleton-containing photosensitive dye, dye mixture comprising the same and dye-sensitized solar cell - Google Patents

Description

Photosensitive dye having an phthalic anhydride skeleton, photosensitive dye mixture containing the same, and dye-sensitized solar cell

The present invention relates to a photosensitizing dye, and more particularly to a photosensitive dye having a perylene-3,4-dicarboxylic anhydride skeleton, a photosensitive dye mixture comprising the same, and a dye-sensitized solar cell.

"Electronically coupled porphyrin-arene dyads for dye-sensitized solar cells" published by Cheng-Wei Lee et al. in 2011 [ Dyes and Pigments 91 (2011) 317-323] discloses a compound P1 for dye-sensitized solar cells. , its chemical structure is: The LUMO of the compound P1 is too close to the energy level of TiO ₂ , so that there is not enough driving force to allow electrons to be injected onto the TiO ₂ , resulting in poor photoelectric conversion efficiency of the dye-sensitized solar cell.

Accordingly, a first object of the present invention is to provide a photosensitive dye having a phthalic anhydride skeleton.

Thus, the photosensitive dye having the phthalic anhydride skeleton of the present invention has the structure of the formula (I):

In the formula (I), R ¹ and R ² each independently represent a C ₁ to C ₁₆ linear alkyl group or a C ₃ to C ₁₆ branched alkyl group.

Therefore, the second object of the present invention is to provide a light-sensitive Dye mixture.

The photosensitive dye mixture comprises a photosensitive dye having a purple structure and the above photosensitive dye having an anhydride structure.

Accordingly, a third object of the present invention is to provide a dye-sensitized solar cell.

Thus, the dye-sensitized solar cell of the present invention comprises a photosensitive dye mixture as described above.

The effect of the invention: the photosensitive dye having the phthalic anhydride skeleton of the invention can be used together with a photosensitive dye having a purple structure, and the dye sensitized solar cell prepared subsequently has high photoelectric conversion efficiency.

The contents of the present invention will be described in detail below:

Preferably, R ¹ and R ² each independently represent a C ₃ to C ₁₆ branched alkyl group.

Preferably, R ¹ and R ² each independently represent a C ₁ to C ₁₆ linear alkyl group.

Preferably, the formula (I) represents the following compounds:

More preferably, the formula (I) represents the following compounds:

More preferably, the formula (I) represents the following compounds:

The photosensitive dye having the phthalic anhydride skeleton of the present invention can be prepared by selecting appropriate reactants and reaction conditions according to the changes of R ¹ and R ² , and the reaction preparation method can be changed according to a technique well known in the art. A method for preparing the photosensitive dye compound, comprising the steps of: (1). a compound having the structure of formula (II) and N-(2,6-diisopropyl) in the presence of a strong base, a solvent and a catalyst. Amination of (N-(2,6-diisopropyl phenyl)-9-bromo-3,4-perylenedicarboximide] to amination a compound having the structure of the formula (III); and the step (2). subjecting the compound having the structure of the formula (III) to a hydrolysis reaction using a strong base in the presence of a solvent to obtain the skeleton having an anhydride Photosensitive dyes:

In the formulae (II) and (III), R ¹ and R ² each independently represent a C ₁ to C ₁₆ linear alkyl group or a C ₃ to C ₁₆ branched alkyl group. Wherein, the preparation method of the compound having the structure of the formula (II) can be prepared according to the change of R ¹ and R ² by using appropriate reactants and reaction conditions, and the reaction preparation method can be changed according to a technique well known in the art.

The strong base, solvent and catalyst in the step (1), the strong base and the solvent in the step (2) are not particularly limited in the invention, and can be selected according to techniques well known in the art. In a specific embodiment of the present invention, the strong base in the step (1) is, for example but not limited to, sodium butoxide (NaO t Bu); the catalyst in the step (1) is, for example but not limited to, tris(dibenzylidene). Acetone) dipalladium [Pd ₂ (dba) ₃ ], tri- t- butylphosphine; solvent in step (1) such as, but not limited to, toluene; strong base in step (2) For example, but not limited to, potassium hydroxide (KOH); the solvent in step (2) is for example but not limited to isopropanol.

The photosensitive dye mixture of the present invention mainly comprises a photosensitive dye having a purple structure and the aforementioned photosensitive dye having an anhydride structure.

The structure and manufacturing method of the dye-sensitized solar cell of the present invention are well known in the art, and therefore, only the structure of the dye-sensitized solar cell of the present invention will be briefly described below. The following statements are merely illustrative and are not to be construed as limiting the invention.

The dye-sensitized solar cell comprises an electrolyte, a photo electrode, and a counter electrode. The photoelectrode and the pair of electrodes are arranged at intervals and are disposed in the electrolyte.

The electrolyte contains a redox pair of iodine.

The photoelectrode comprises a transparent conductive substrate, a porous film disposed on the surface of the transparent conductive substrate, and the porous film adsorbs the photosensitive dye having the phthalic anhydride skeleton of the present invention.

The pair of electrodes includes a transparent conductive substrate and a platinum film formed on the surface of the transparent conductive substrate.

The transparent electrode of the photoelectrode and the pair of electrodes is a transparent substrate coated with a transparent conductive film such as indium tin oxide (ITO) or fluorine tin oxide (FTO). The material of the transparent substrate is, for example but not limited to, polyethylene, polypropylene, polyimine, polymethyl methacrylate, polycarbonate, polyethylene terephthalate, glass, or the like.

The material of the porous film is, for example but not limited to, titanium dioxide.

The present invention will be further illustrated by the following examples, but it should be understood that this embodiment is intended to be illustrative only and not to be construed as limiting.

[Example 1] Photosensitive dye having an phthalic anhydride skeleton (hereinafter referred to as Compound A)

Preparation of Compound A-1: 0.0376 mol of 4-nitrophenol, 0.06 mol of 1-bromo-2-butyl-octane, 0.1 mol of Potassium carbonate (K ₂ CO ₃ ) was dissolved in 125 mL of acetone to obtain a reaction liquid. The reaction solution was refluxed under nitrogen for 36 hours. After completion of the reaction, the reaction mixture was filtered, concentrated, and extracted with ethyl acetate and water. The crude product was subjected to column chromatography (the mixture was a mixture of ethyl acetate and n-hexane, ethyl acetate: n-hexane = 1: 20) to afford compound A-1 as a pale yellow liquid (yield 55%) ). Spectroscopic analysis of compound A-1: ¹ H NMR (CDCl ₃ , 400 MHz), δ (ppm): 8.19 (d, 2H, J = 9.2 Hz), 6.94 (d, 2H, J = 9.2 Hz), 3.92 (d) , 2H, J = 5.6 Hz), 1.89 to 1.71 (m, 1H), 1.51 to 1.19 (m, 16H), 0.98 to 0.80 (m, 6H). Preparation of Compound A-2: 20.3 mmol of Compound A-1 was dissolved in 108 mL of tetrahydrofuran (THF), and then 1.7 mmol of a palladium carbon catalyst (Pd/C) was added to obtain a reaction liquid. The reaction solution was purged with hydrogen at a pressure of 4 atm and reacted for 40 hours. After completion of the reaction, the reaction mixture was suction filtered with n-hexane and concentrated to give a crude product. The crude product was subjected to column chromatography (chromic acid ethyl acetate, mixture of n-hexane and triethylamine, ethyl acetate: n-hexane: triethylamine = 1:10:0.01) to give a slightly yellow liquid. Compound A-2 (yield 68%). Spectroscopic analysis of compound A-2: ¹ H NMR (CDCl ₃ , 400 MHz), δ (ppm): 6.74 (d, 2H, J = 8.8 Hz), 6.64 (d, 2H, J = 8.8 Hz), 3.75 (d) , 2H, J = 5.8 Hz), 3.25 (s, 2H), 1.72 (m, 1H), 1.47 to 1.21 (m, 16H), 0.89 (m, 6H).

Preparation of Compound A-3: 0.038 mol of 4-bromophenol, 0.06 mol of 1-bromo-2-butyl-octane, 0.19 mol of carbonic acid Potassium was dissolved in 200 mL of acetone to obtain a reaction solution. The reaction solution was refluxed under nitrogen for 36 hours. After completion of the reaction, the reaction mixture was filtered, concentrated, and extracted with ethyl acetate and water. The crude product was subjected to column chromatography (yield: n-hexane) to afford Compound A-3 (yield: 58%). Spectroscopic analysis of compound A-3: ¹ H NMR (CDCl ₃ , 400 MHz), δ (ppm): 7.36 (d, 2H, J = 9.0 Hz), 6.77 (d, 2H, J = 9.0 Hz), 3.79 (d) , 2H, J = 5.6 Hz), 1.84~1.69 (m, 1H), 1.49~1.23 (m, 18H), 0.89 (m, 6H).

Preparation of Compound A-4: 4.1 mmol of Compound A-3 was dissolved in 3.3 mL of toluene under nitrogen, followed by addition of 0.127 mmol of tris(dibenzylideneacetone)dipalladium [Pd ₂ (dba) ₃ ], 0.127 mmol of 1,1'-bis(diphenylphosphino)ferrocene (dppf) and 13 mmol of sodium tributoxide (NaO t Bu), after reacting for 10 minutes, 5.1 mmol of compound A-2 was further After 3.3 mL of toluene was dissolved, it was added to obtain a reaction liquid. The reaction solution was refluxed at an oil bath temperature of about 100 ° C for 16 hours. After completion of the reaction, the reaction solution was subjected to suction filtration using celite, and concentrated to give a crude product. The crude product was subjected to column chromatography (chromatographic mixture of dichloromethane and n-hexane, methylene chloride: n-hexane = 1:2) to afford compound A-4 as a yellow liquid (yield 54.8%) . Spectroscopic analysis of the compound A-4: ¹ H NMR (CDCl ₃ , 400 MHz), δ (ppm): 6.93 (s, 4H), 6.83 (d, 4H, J = 8.8 Hz), 5.28 (s, 1H), 3.81 (d, 4H, J = 5.6 Hz), 1.77 (m, 2H), 1.52 to 1.27 (m, 32H), 0.94 to 0.89 (m, 12H).

Preparation of Compound A-5: 0.18 mmol of N-(2,6-diisopropylphenyl)-9-bromo-3,4-decyldimethylimine [N-(2,6-diisopropyl-) Phenyl)-9-bromo-3,4-perylenedicarboximide], 0.009 mmol of Pd ₂ (dba) ₃ , 0.54 mmol of NaO t Bu were mixed and vacuumed for 10 minutes, and then 0.045 mmol of tris(t-butyl) was added. phosphorus (tri- t -butylphosphine, P (t -Bu) 3), 0.36mmol of the compound a-4, and 35mL of toluene, to obtain a reaction solution. The reaction solution was placed in an oil bath and reacted for 12 hours under nitrogen and an oil bath temperature of 90 °C. After completion of the reaction, the reaction mixture was concentrated to give a crude material. The crude product was subjected to column chromatography (chromatographic mixture of dichloromethane and n-hexane, methylene chloride: n-hexane = 2:1) to afford compound A-5 (yield: 75%) . Spectroscopic analysis of compound A-5: ¹ H NMR (CDCl ₃ , 400 MHz), δ (ppm): 8.61 (t, 2H, J = 7.6 Hz), 8.40 (t, 2H, J = 7.2 Hz), 8.32 (d) , 1H, J = 8.4 Hz), 8.29 (d, 1H, J = 8.0 Hz), 8.09 (d, 1H, J = 8.4 Hz), 7.46 (q, 2H, J = 7.8 Hz), 7.33 (d, 2H) , J = 8.0 Hz), 7.25 (d, 1H, J = 7.6 Hz), 6.99 (d, 4H, J = 8.4 Hz), 6.81 (d, 4H, J = 8.4 Hz), 3.80 (d, 4H, J =5.4Hz), 2.81~2.74(m,2H), 1.75(m,2H), 1.50~1.25(m,32H), 1.18(d,12H, J =6.8Hz), 0.91~0.83(m,12H) .

Preparation of Compound A: 0.15 mmol of Compound A-5 and 150 mmol of KOH were dissolved in isopropanol to obtain a reaction liquid. After the reaction solution was refluxed under nitrogen for 12 hours, it was reduced to 25 ° C, and then acetic acid was added to become weakly basic, and the reaction was carried out for 5 hours. After the reaction was completed, water was added to the reaction mixture, and filtered to give a crude product. The crude product was subjected to column chromatography (the chromatography liquid was a mixture of dichloromethane and n-hexane, methylene chloride: n-hexane = 2:1), and then recrystallized from dichloromethane and methanol to give blue crystals. Compound A (yield 66%). Spectroscopic analysis of Compound A: ¹ H NMR (CDCl ₃ , 400 MHz), δ (ppm): 8.48 (t, 2H, J = 7.6 Hz), 8.38 (d, 1H, J = 7.5 Hz), 8.32 (d, 2H) , J = 8.2 Hz), 8.22 (d, 1H, J = 8.2 Hz), 8.11 (d, 1H, J = 8.4 Hz), 7.45 (t, 1H, J = 8.0 Hz), 7.23 (d, 1H, J = 8.4 Hz), 6.99 (d, 4H, J = 8.8 Hz), 6.81 (d, 4H, J = 8.8 Hz), 3.79 (d, 4H, J = 5.6 Hz), 1.80 to 1.68 (m, 2H), 1.50~1.23 (m, 32H), 0.89 (q, 12H, J = 6.8 Hz).

[Example 2] Photosensitive dye having an phthalic anhydride skeleton (hereinafter referred to as Compound B)

Preparation of Compound B-1: 6.2 mmol of 1-bromo-4-(hexyloxy)benzene] was dissolved in 5 mL of toluene under nitrogen, and 0.19 mmol of Pd was further added. ₂ (dba) ₃ , 0.19 mmol of dppf and 19.4 mmol of NaO t Bu were added. After 10 minutes of reaction, 7.7 mmol of 4-(hexyloxy)benzenamine was dissolved in 5 mL of toluene. After the addition, the reaction liquid was obtained. The reaction solution was refluxed at an oil bath temperature of about 100 ° C for 16 hours. After completion of the reaction, the reaction solution was subjected to suction filtration using celite, and concentrated to give a crude product. The crude product was subjected to column chromatography (the chromatograph was a mixture of dichloromethane and n-hexane, methylene chloride: n-hexane = 1:2) to give a yellow liquid, which was recrystallized from n-hexane to give a white solid. Compound B-1 (yield 57%). Spectroscopic analysis of compound B-1: ¹ H NMR (400 MHz, DMSO), δ (ppm): 7.46 (s, 1H), 6.88 (d, 4H, J = 8.8 Hz), 6.77 (d, 4H, J = 8.8 Hz), 3.85 (t, 4H, J = 6.6 Hz), 1.64 (dd, 4H, J = 14.6, 6.8 Hz), 1.38 (dd, 4H, J = 12.2, 4.6 Hz), 1.31 to 1.22 (m, 8H) ), 0.86 (t, 6H, J = 6.8 Hz).

Preparation of Compound B-2: 0.35 mmol of N-(2,6-diisopropylphenyl)-9-bromo-3,4-decyldimethylimine, 0.017 mmol of Pd ₂ (dba) ₃ After evacuation of 1.05 mmol of NaO t Bu for 10 minutes, 0.087 mmol of tris(t-butyl)phosphine, 0.7 mmol of compound B-1 and 50 to 100 mL of toluene were added to obtain a reaction liquid. The reaction solution was reacted for 12 hours under a nitrogen gas and oil bath temperature of 90 °C. After the reaction was completed, the reaction mixture was concentrated to give a crude product. This crude product was subjected to column chromatography (chromic chromatography mixture of dichloromethane and n-hexane, methylene chloride: n-hexane = 2:1) to give a dark blue compound B-2 (yield 59%) . Spectroscopic analysis of compound B-2: ¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 8.63 (t, 2H, J = 7.8 Hz), 8.42 (dd, 2H, J = 7.8, 4.1 Hz), 8.36 (d, 1H, J = 8.0 Hz), 8.32 (d, 1H, J = 8.0 Hz), 8.09 (d, 1H, J = 8.4 Hz), 7.52 to 7.42 (m, 2H), 7.34 (d, 2H, J = 8.0 Hz), 7.26 (d, 1H, J = 8.4 Hz), 6.99 (d, 4H, J = 8.8 Hz), 6.81 (d, 4H, J = 8.8 Hz), 3.93 (t, 4H, J = 6.6 Hz), 2.86~2.72 (m, 2H), 1.84~1.71 (m, 4H), 1.48~1.42 (m, 4H), 1.39~1.30 (m, 8H), 1.19 (d, 12H, J = 6.8Hz) ), 0.91 (t, 6H, J = 6.8 Hz).

Preparation of Compound B: 0.14 mmol of Compound B-2 and 30.3 mmol of KOH were dissolved in isopropanol to obtain a reaction liquid. The reaction solution was refluxed under nitrogen for 12 hours, and then lowered to 25 ° C, and then acetic acid was added thereto to make the reaction mixture weakly alkaline and reacted for 5 hours. After the reaction was completed, water was added to the reaction mixture, and the obtained crude product was filtered. This crude product was subjected to column chromatography (the chromatographic solution was a mixture of dichloromethane and n-hexane, dichloromethane: n-hexane = 2:1), and then recrystallized from dichloromethane and methanol to give blue crystals. Compound B (yield 53%). Spectroscopic analysis of Compound B: ¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 8.38 (dd, 2H, J = 8.2, 3.6 Hz), 8.31 (d, 1H, J = 7.4 Hz), 8.26 (d) , 1H, J = 8.4 Hz), 8.21 (d, 1H, J = 8.2 Hz), 8.11 (t, 2H, J = 8.6 Hz), 7.43 (t, 1H, J = 8.0 Hz), 7.22 (d, 1H) , J = 8.0 Hz), 7.00 (d, 4H, J = 8.8 Hz), 6.82 (d, 4H, J = 8.8 Hz), 3.93 (t, 4H, J = 6.6 Hz), 1.82 to 1.72 (m, 4H) ), 1.45 (d, 4H, J = 6.9 Hz), 1.38 to 1.30 (m, 8H), 0.91 (t, 6H, J = 6.8 Hz).

[Comparative Example 1]

Refer to the article "Electronically coupled porphyrin-arene dyads for dye-sensitized solar cells" to reveal the compound P1{9-(bis(4-tert-butylphenyl)amino)perylene-3,4-dicarboxylic anhydride}, which has the chemical structural formula:

[Quality evaluation]

1. Ultraviolet/visible absorption spectroscopy: The maximum absorption wavelength (λ _{max )} of the photosensitive dyes having the phthalic anhydride skeleton of Examples 1 to 2 was measured by an ultraviolet/visible spectrometer (label: Varian, model: Cary 50 CONC). Nm), and the molar extinction coefficient (ε, unit: 10 ^-3 M ^-1 cm ^-1 ). Wherein Examples 1 to 2 was dissolved in tetrahydrofuran (THF) at a temperature of 258K and under measurement; measurement conditions: a concentration of 3 × 10 ^-6 M, the measurement range of 300nm to 800 nm, scan rate of 600nm / min. .

2. Fluorescence emission spectrum: The maximum light-emitting wavelength (λ _max , unit: nm) of the photosensitizing dyes having the phthalic anhydride skeletons of Examples 1 to 2 was measured by a fluorescence spectrometer (brand: JASCO, model: FP-6000). Among them, Examples 1 to 2 were dissolved in tetrahydrofuran (THF) and measured at a temperature of 258 K; the measurement conditions were as follows: a concentration of 3 × 10 ^-6 M, a measurement range of 300 nm to 800 nm, and a scanning rate of 600 nm/min.

3. Electrochemical properties (HOMO, LUMO, energy level difference E _0-0 ): The oxidation potentials of the photosensitive dyes having the phthalic anhydride skeleton of Examples 1 to 2 were measured by cyclic voltammetry (CV) and oxidized. The potential is calculated to obtain the HOMO energy level. And by normalizing the ultraviolet/visible absorption spectrum and the fluorescence emission spectrum, an intersection is obtained to calculate the energy level difference E _0-0 . Finally, the LUMO energy level is calculated by the HOMO energy level and the energy level difference E _0-0 . Among them, the measurement method of cyclic voltammetry is as follows: Cyclic voltammetry is performed using a three-electrode potentiometer (manufacturer: CH Instrument, model: Model 750A). The three-electrode potentiometer includes: (1) a working electrode: a glassy carbon electrode having an area of 0.07 cm ² (manufacturer: BAS Instruments, USA), (2) an auxiliary electrode: a platinum wire having a diameter of 0.25 mm, (3) Reference electrode: self-made Ag/AgCl (saturated KCl), corrected to a saturated calomel electrode with an error of ±5 mV before use, and (4) electrolyte: tetrabutylammonium hexafluorophosphate , TBAPF ₆ ). The oxidation potential of the compound to be tested was measured at a scanning speed of 0.1 V/s, and the measured oxidation potential was calculated by using ferrocene (oxidation potential: -4.8 eV) as a reference potential, and the HOMO energy level was calculated.

4. Performance of dye-sensitized solar cells (open circuit voltage, short-circuit current, fill factor, and photoelectric conversion efficiency): Clean a fluorine-doped tin oxide (FTO) conductive glass with a neutral detergent and clean it with ultrasonic shock for 30 minutes. The excess detergent was washed with water; the FTO conductive glass was then washed with ethanol and acetone, and ultrasonically washed for 30 minutes, and finally with ethanol to obtain a cleaned FTO conductive glass. The washed FTO conductive glass was treated with a 40 mM aqueous solution of titanium tetrachloride, and then placed in an oven at 72 ° C for 1 hour, and then washed with deionized water and ethanol to obtain a treated FTO conductive glass. A porous titanium dioxide layer (about 20 nm) is formed on the treated FTO conductive glass by screen printing, and each layer is placed on a 125 ° C hot plate for 5 minutes until the desired thickness is 20 nm, and finally A titanium dioxide scattering layer (about 400 nm) was printed on the porous titania layer to prepare a titania electrode. The titania electrode was heated and sintered at a heating rate of 10 ° C / min, and maintained at 500 ° C for 30 minutes, and then naturally cooled to 80 ° C, and then the sintered titanium dioxide electrode was immersed in a dichloromethane solution containing a photosensitizing dye ( A dye concentration of 0.5 mM was used to prepare a photoelectrode. A platinum electrode was cleaned with a neutral detergent and ultrasonically shaken for 30 minutes, then rinsed with deionized water and ethanol, and then immersed in a poly(N-vinyl-2-pyrrolidone)-protected Ptna at 45 °C. Aqueous solution of rice particles [0.5 g of PVP (weight average molecular weight of 8000) was dissolved in 44 mL of deionized water, and then 0.2 g of chloroplatinic acid and 0.5 M of NaBH ₄ aqueous solution were added, followed by stirring for 30 minutes to prepare] After a minute, the platinum electrode was taken out, washed with deionized water, and then heated at a temperature increase rate of 10 ° C / min, and heat-treated at 325 ° C for 30 minutes to obtain a pair of electrodes. The photoelectrode, the hot melt pad (thickness 25 μm) and the pair of electrodes were sequentially stacked to obtain a laminate. The laminate was then placed in a heating apparatus at a temperature of 125 ° C for encapsulation. In the hole of the counter electrode of the laminate, a syringe needle was used to inject 0.2 ml of a Z959 standard volatile electrolyte [Z959 standard volatile electrolyte, which is 1.0 M 1,3-dimethylimidazolium iodide (1,3-dimethylimidazolium iodide, DMII), 0.03 M iodine, 0.5 M tert-butylpyridine and 0.1 M guanidinium thiocyanate (GuCN) were mixed to obtain a mixture, and the mixture was acetonitrile and valeronitrile ( The volume ratio is 85:15) dissolved]. Finally, the holes were covered with a hot melt adhesive film, and a cover glass was attached, and the surface was heat-sealed (105 ° C). All packaging processes were carried out in a glove box with a relative humidity of less than 20% to obtain a dye-sensitized solar cell.

The dye-sensitized solar cell was irradiated with a solar simulator (Solar Simulator System, manufacturer: Yamashita Denso, model: YSS-50S_80A), with a power meter (Keithley 2400) and photoelectric conversion efficiency measurement The system (Peccell PEC-S20) measures the open circuit voltage, short circuit current, fill factor, and photoelectric conversion efficiency of the dye-sensitized solar cell.

As is apparent from Table 1, the dye-sensitized solar cells prepared by the photosensitive dyes having the phthalic anhydride skeletons of Examples 1 and 2 have better photoelectric conversion efficiency than Comparative Example 1.

As described above, by using the photosensitive dye having the phthalic anhydride skeleton of the present invention, the dye-sensitized solar cell produced has high photoelectric conversion efficiency, and thus the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

Claims (5)

a photosensitive dye having a phthalic anhydride skeleton selected from The photosensitive dye having an phthalic anhydride skeleton as described in claim 1 is selected from . The photosensitive dye having an phthalic anhydride skeleton as described in claim 1 is selected from . A photosensitive dye mixture comprising a photosensitizing dye having a succulent structure and a photosensitive dye having an phthalic anhydride skeleton according to any one of claims 1 to 3. A dye-sensitized solar cell comprising the photosensitive dye mixture of claim 4.