KR101184189B1 - Dye-sensitized solar cell and photoanode thereof - Google Patents

Abstract

상기의 식에서, D₁, D₂, R₁, R₂, R₃, R₄, B, 및 n 는 본 명세서 내에서 정의된 바와 같다.
이러한 두 종류의 유기감응염료는 비교되는 흡수 피크를 가지므로, 본 발명의 광양극은 더 큰 파장 길이 범위를 갖는 태양 스펙트럼을 흡수할 수 있다. 따라서, 본 발명의 광양극을 사용하는 염료감응 태양전지는 뛰어난 광전변환 효율을 가진다. Dye-sensitized solar cells, photoanodes thereof, and methods of making the same are disclosed. The photoanode of the dye-sensitized solar cell of the present invention is made of a porous semiconducting layer that absorbs two types of organosensitive dyes, which are represented by the following general formula (I):
<Formula (I)>

In the above formula, D ₁ , D ₂ , R ₁ , R ₂ , R ₃ , R ₄ , B, and n are as defined herein.
Since these two types of organic sensitizers have comparable absorption peaks, the photoanode of the present invention can absorb the solar spectrum with a larger wavelength length range. Therefore, the dye-sensitized solar cell using the photoanode of the present invention has excellent photoelectric conversion efficiency.

Description

DYE-SENSITIZED SOLAR CELL AND PHOTOANODE THEREOF

The present invention relates to a novel photoanode for dye-sensitized solar cells (DSCs) made of porous semiconducting layers that continuously absorb various sensitive dyes, and more particularly various organic sensitive dyes. A photoanode for a DSC made of a porous semiconducting layer that absorbs continuously.

With the development of industrial technology, humans all over the world today faced two very serious problems: energy crisis and environmental pollution. One of the effective means to solve the global energy crisis and reduce environmental pollution is solar cells that can convert solar energy into electrical energy. Among these solar cells, dye-sensitized solar cells have become increasingly promising due to their excellent properties such as low production cost, mass production, large fluidity, light transmittance and applicability to buildings.

In recent years, Gratzel et al. Published a series of papers on dye-sensitized solar cells that demonstrate the practicality of dye-sensitized solar cells (eg, O'Regan, B .; Gratzel, M. Nature 1991, 353, 737). . The general structure of a dye-sensitized solar cell is composed of an anode, a cathode, nano-sized TiO2, a dye and an electrolyte, among which dye plays a very important role in the conversion efficiency of the dye-sensitized solar cell. The dyes suitable for dye-sensitized solar cells should have a broad range of absorption spectra, high molar absorption coefficients, thermal stability and light stability.

Currently ruthenium complexes are sensitizing dyes with the highest conversion efficiencies. However, the manufacturing cost of the ruthenium complex is high, and when the ruthenium complex is widely used, there may be a problem that the supply is insufficient. Organic sensitizing dyes have the advantage of high molar absorption coefficients. In addition, it is possible to produce a variety of organic sensitizing dyes through molecular design. Therefore, dye-sensitized solar cells with different colors can be produced by the use of other organic-sensitive dyes to improve the application flexibility of the dye-sensitized solar cells. In addition, it is also possible to change the color of the dye-sensitized solar cell to match the color of the article. Currently, dye derivatives are described, for example, in Coumarin (Hara, K .; Sayama, K .; Arakawa, H .; Ohga, Y .; Shinpo, A .; Sug, S. Chem. Commun., 2001, 569), Indoline (Horiuchi, T .; Miura, H .; Sumioka, K .; Uchida, SJ Am. Chem. Soc., 2004, 126 (39), 12218) and Merocyanine (Otaka, H .; Kira, M .; Yano, K .; Ito, S .; Mitekura, H .; Kawata, T .; Matsui, FJ Photochem. Photobiol.A: Chem .; 2004, 164, 67), It is already applied in the manufacture of dye-sensitized solar cells.

However, only a small amount of energy in the solar spectrum can be used because the wavelength range that the organodyes can absorb is narrow. Therefore, the photoelectric conversion efficiency of the dye-sensitized solar cell made of an organic sensitizer is limited and difficult to improve. Recently, Gratzel et al. Have improved the photoelectric conversion efficiency of dye-sensitized solar cells through a co-absorption process in which two types of organic dyes are absorbed together as compared to dye-sensitized solar cells made of one organic dye. Announced that it could be. (Kung D .; Walter P .; Nuesch F .; Kim S .; Ko J .; Comte P .; Zakeeruddin S. M .; Zakeeruddin M. K .; Gratzel, M. Langmuir 2007, 10906-10909). Additionally, Toshiba Corporation announced that dye-sensitized solar cells manufactured through co-absorption processes using organic and inorganic dyes improve photoelectric conversion efficiency (JP 2000-195569). .

The co-absorption process using suitable sensitizing dyes has a great impact on the photoelectric conversion efficiency of dye sensitized solar cells. Therefore, it is desirable to provide a combination of sensitizing dyes that are jointly absorbed in order to improve the photoelectric conversion efficiency of dye-sensitized solar cells.

It is an object of the present invention to provide a novel photoanode for dye-sensitized solar cells, which produces a porous semiconducting layer that continuously absorbs two or more kinds of sensitizing dyes.

Another object of the present invention is to provide a novel photoanode for dye-sensitized solar cells, which manufactures a porous semiconducting layer that continuously absorbs two or more types of organosensitive dyes.

Another object of the present invention is to provide a novel dye-sensitized solar cell for producing a porous semiconducting layer that continuously absorbs two or more kinds of sensitizing dyes.

Furthermore, another object of the present invention is to provide a novel dye-sensitized solar cell, which manufactures a porous semiconducting layer that continuously absorbs two or more types of organosensitive dyes.

The maximum absorption wavelengths of the dye compounds used in the dye-sensitized solar cells of the present invention are complementary to each other, so that the dye compounds can be absorbed in a larger wavelength range of the solar spectrum. Therefore, the dye-sensitized solar cell of the present invention exhibits excellent photoelectric properties.

The present invention also provides a method of manufacturing a dye-sensitized solar cell, wherein the prepared dye-sensitized solar cell exhibits better photoelectric conversion efficiency.

The photoanode of the present invention consists of a transparent substrate, a transparent conductive layer, a porous semiconducting layer and dye compounds.

The photoanode of the present invention is not particularly limited as long as the material of the substrate is a transparent material. Preferably, the material of the transparent substrate is a transparent material having good moisture resistance, solvent resistance and weather resistance. Therefore, the dye-sensitized solar cell can resist moisture or gas from the outside by the transparent substrate. Specific examples of transparent substrates include transparent inorganic substrates such as quartz and glass; Transparent plastic substrates such as polyethylene terephthalate (PET), polyethylene 2,6-naphthalate (PEN), polycarbonate (PC), polyethylene (PE), polypropylene (PP) and polyimide (PI) It is not limited. In addition, the thickness of the transparent substrate is not particularly limited and may vary depending on the requirements regarding the transmittance and the characteristics of the dye-sensitized solar cell. Preferably, the material of the transparent substrate is glass.

Furthermore, in the photoanode of the present invention, the material of the transparent conductive layer may be indium tin oxide (ITO), fluorinated tin oxide (FTO), ZnO-Ga ₂ O ₃ , ZnO-Al ₂ O ₃ or tin oxide. .

In addition, in the photoanode of the present invention, the porous semiconducting layer may be composed of semiconductor particles. Suitable semiconductor materials may include Si, TiO ₂ , SnO ₂ , ZnO, WO ₃ , Nb ₂ O ₅ , TiSrO ₃ , or mixtures thereof. Preferably, the semiconductor material is a TiO ₂ material. The average diameter of the semiconductor material may be 5 to 500 nm. Preferably, the average diameter of the semiconductor material may be 10 to 50 nm. Furthermore, the thickness of the porous semiconducting layer is 5-25 μm.

According to the photoanode of the invention, the dye consists of:

(a) the first organic sensitizer represented by the following general formula (I) or salts thereof,
<Formula (I)>

delete

In <Formula (I)>,

R ₁ , R ₂ , R ₃ and R ₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or halogen, n is an integer of 1, 2 or 3;

,

,

또는

이거나, D₁, D₂ 및 N의 결합은 모여서

,

또는

을 형성하고, 상기의 식에서, R₅, R₆, R₇, R₈, R₁₀, R₁₁, R₁₃ 및 R₁₄는 각각 독립적으로 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 아미노 또는 할로겐이며, R₉, R₁₂ 및 R₁₅는 각각 독립적으로 H 또는 C₁~C₁₂ 알킬임;D ₁ and D ₂ are each independently C ₁ -C ₁₂ alkyl,

,

,

or

Or a combination of D ₁ , D ₂ and N

,

or

Wherein R ₅ , R ₆ , R ₇ , R ₈ , R ₁₀ , R ₁₁ , R ₁₃ and R ₁₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy , Amino or halogen, R ₉ , R ₁₂ and R ₁₅ are each independently H or C ₁ to C ₁₂ Alkyl;

,

,

,

,

,

또는

이고, 상기 R₁₆, R₁₇ 및 R₁₈는 각각 독립적으로 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 또는 할로겐이며, R₁₉, R₂₀, R₂₁ 및 R₂₂ 는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬이고, Z는 O, S, 또는 Se임; 및B is

,

,

,

,

,

or

R ₁₆ , R _17, and R ₁₈ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, and R ₁₉ , R ₂₀ , R _21, and R ₂₂ are each independently H, or C ₁ -C ₁₂ alkyl, Z is O, S, or Se; And

(b) The second organic sensitizing dye having a difference in maximum absorption wavelength from the first organic sensitizing dye (a) of 50 nm or more.

In formula (I), R ₁ , R ₂ , R ₃ and R ₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, n is 1, 2, or 3 to be. Preferably, R ₁ , R ₂ , R ₃ and R ₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or halogen and n is 1 or 2. More preferably, R ₁ , R ₂ , R ₃ and R ₄ are each independently H, C ₁ -C ₁₂ alkyl or C ₁ -C ₁₂ alkoxy, n is 1 or 2. Further preferably, R ₁ , R ₂ , R ₃ and R ₄ are each independently H, C ₁ -C ₁₂ alkyl or C ₁ -C ₁₂ alkoxy, n is 1. Most preferably, R ₁ , R ₂ , R ₃ and R ₄ are each independently H or C ₁ to C ₁₂ alkyl, and n is 1.

,

,

또는

이거나, D₁, D₂ 및 N의 결합은 모여서

,

, 또는

을 형성하고(예를 들어, C4~C6 사이클로헤테로 알킬렌), 상기 R₅, R₆, R₇, R₈, R₁₀, R₁₁, R₁₃, 및 R₁₄는 각각 독립적으로 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 아미노, 또는 할로겐이고, R₉, R₁₂, 및 R₁₅ 는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬이다. 바람직하게도, D₁ 및 D₂는 각각 독립적으로 C₁~C₁₂ 알킬,

, 또는

이며, 상기 R₅, R₆, R₇, 및 R₈는 각각 독립적으로 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 아미노, 또는 할로겐이고, R₉ 는 H이며, 또는 C₁~C₁₂ 알킬이다. 더 바람직하게도, D₁ 및 D₂는 각각 독립적으로 C₁~C₁₂ 알킬,

또는

이며, 상기 R₅, R₆, R₇, 및 R₈는 각각 독립적으로 H, C₁~C₁₂ 알킬, 또는 C₁~C₁₂ 알콕시이고, R₉는 H 또는 C₁~C₁₂ 알킬이다. 가장 바람직하게도, D₁ 및 D₂는 각각 독립적으로 C₁~C₁₂ 알킬,

또는

이고, 상기 R₅, R₆, R₇, R₈ 및 R₉는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬이다.In Formula (I), D ₁ and D ₂ are each independently C ₁ ~ C ₁₂ alkyl,

,

,

or

Or a combination of D ₁ , D ₂ and N

,

, or

(E.g., C4-C6 cycloheteroalkylene), wherein R ₅ , R ₆ , R ₇ , R ₈ , R ₁₀ , R ₁₁ , R ₁₃ , and R ₁₄ are each independently H, C ₁ ˜C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, amino, or halogen, and R ₉ , R ₁₂ , and R ₁₅ are each independently H, or C ₁ -C ₁₂ alkyl. Preferably, D ₁ And D ₂ are each independently C ₁ -C ₁₂ alkyl,

, or

R ₅ , R ₆ , R ₇ , and R ₈ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, amino, or halogen, R ₉ is H, or C ₁ ˜C ₁₂ alkyl. More preferably, D ₁ And D ₂ are each independently C ₁ -C ₁₂ alkyl,

or

R ₅ , R ₆ , R ₇ , and R ₈ are each independently H, C ₁ -C ₁₂ alkyl, or C ₁ -C ₁₂ alkoxy, and R ₉ is H or C ₁ -C ₁₂ alkyl. Most preferably, D ₁ And D ₂ are each independently C ₁ -C ₁₂ alkyl,

or

R ₅ , R ₆ , R ₇ , R ₈ and R ₉ are each independently H or C ₁ to C ₁₂ alkyl.

일 수 있고, 상기 R₅, R₆ 및 R₇는 각각 독립적으로 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 아미노, 또는 할로겐이다. 바람직하게도 D₁ 및 D₂에서 R₅, R₆ 및 R₇는 각각 독립적으로 H, C₁~C₁₂ 알킬, 또는 C₁~C₁₂ 알콕시이다. 더 바람직하게는, D₁ 및 D₂에서 R₅, R₆ 및 R₇는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬이다. 가장 바람직하게도, D₁ 및 D₂에서 R₅는 H이며, R₆ 및 R₇는 각각 독립적으로 C₁~C₁₂ 알킬이다. 가장 바람직하게도, D₁ 및 D₂에서 R₅는 H이고, R₆, 및 R₇는 각각 독립적으로 C₁~C₁₂ 알킬이다.In addition, according to one aspect of the present invention, in formula (I), D ₁ , and D ₂ are each independently C ₁ -C ₁₂ alkyl or

And R ₅ , R ₆ and R ₇ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, amino, or halogen. Preferably R ₅ , R ₆ and R ₇ in D ₁ and D ₂ are each independently H, C ₁ -C ₁₂ alkyl, or C ₁ -C ₁₂ alkoxy. More preferably, R ₅ , R ₆ and R ₇ in D ₁ and D ₂ are each independently H, or C ₁ -C ₁₂ alkyl. Most preferably, in D ₁ and D ₂ R ₅ is H and R ₆ and R ₇ are each independently C ₁ -C ₁₂ alkyl. Most preferably, in D ₁ and D ₂ R ₅ is H and R ₆ , and R ₇ are each independently C ₁ -C ₁₂ alkyl.

,

,

,

,

,

, 또는

일 수 있으며, 상기 R₁₆, R₁₇, 및 R₁₈는 각각 독립적으로 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 또는 할로겐이고, R₁₉, R₂₀, R₂₁ 및 R₂₂는 각각 독립적으로 H 또는 C₁~C₁₂ 알킬이며, Z는 O, S, 또는 Se이다. 바람직하게도, B는

,

또는

이고, 상기 R₁₆는 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 또는 할로겐이고, R₁₉, 및 R₂₂ 는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬이고, Z는 O, S, 또는 Se이다. In the formula (I), B is

,

,

,

,

,

, or

Wherein R ₁₆ , R ₁₇ , and R ₁₈ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, and R ₁₉ , R ₂₀ , R _21, and R ₂₂ are Each independently is H or C ₁ -C ₁₂ alkyl, and Z is O, S, or Se. Preferably, B is

,

or

R ₁₆ is H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, R ₁₉ , and R ₂₂ are each independently H, or C ₁ -C ₁₂ alkyl, and Z is O , S, or Se.

,

또는

이고, 상기 R₁₆는 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 또는 할로겐이며, R₁₉, 및 R₂₂는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬이고, Z는 S이다. 가장 바람직하게도, B는

,

또는

이고, 상기 R₁₆, R₁₉, 및 R₂₂ 는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬이며, Z는 S이다.More preferably, B is

,

or

R ₁₆ is H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, R ₁₉ , and R ₂₂ are each independently H, or C ₁ -C ₁₂ alkyl, and Z is S to be. Most preferably, B is

,

or

R ₁₆ , R ₁₉ , and R ₂₂ are each independently H, or C ₁ -C ₁₂ alkyl, and Z is S.

또는

이고, 상기 R₁₆는 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 또는 할로겐이고, R₁₉ 는 H, 또는 C₁~C₁₂ 알킬이며, Z는 O, S, 또는 Se이다. 바람직하게도 B는

, 또는

이고, 상기 R₁₆ 는 H, C₁~C₁₂ 알킬, C₁~C₁₂ 알콕시, 또는 할로겐이고, R₁₉는 H, 또는 C₁~C₁₂ 알킬이며, Z는 S이다. 더 바람직하게, B는

또는

이고, 상기 R₁₆ 는 H, C₁~C₁₂ 알킬, 또는 C₁~C₁₂ 알콕시이고, R₁₉는 H, 또는 C₁~C₁₂ 알킬, Z는 S이다. 더 나아가 더 바람직하게도, B는

, 또는

이고, 상기 R₁₆, 및 R₁₉는 각각 독립적으로 H, 또는 C₁~C₁₂ 알킬, Z는 S이다. 가장 바람직하게도, B는

또는

이고, 상기 R₁₆ 및 R₁₉ 는 H이고, Z는 S이다.Furthermore, according to another aspect of the invention, in the formula (I), B is

or

R ₁₆ is H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, R ₁₉ is H, or C ₁ -C ₁₂ alkyl, and Z is O, S, or Se. Preferably B is

, or

R ₁₆ is H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, R ₁₉ is H, or C ₁ -C ₁₂ alkyl, and Z is S. More preferably, B is

or

R ₁₆ is H, C ₁ -C ₁₂ alkyl, or C ₁ -C ₁₂ alkoxy, R ₁₉ is H, or C ₁ -C ₁₂ alkyl, Z is S. Furthermore, more preferably, B is

, or

R ₁₆ and R ₁₉ are each independently H, or C ₁ to C ₁₂ alkyl, and Z is S. Most preferably, B is

or

Wherein R ₁₆ and R ₁₉ are H and Z is S.

Particular examples of the first organodye represented by the formula (I) are as follows:

(I-1)

(I-2)

(I-3)

(I-4)

(I-5)

(I-6)

Specific examples of the second organic sensitizer (b) are as follows:

(II-1)

(II-2)

In the present invention, the molecules of the sensitizing dye are in the form of the free acid. However, the actual form of the sensitizing dye may be a salt, perhaps an alkali metal salt or a quaternary ammonium salt.

The dye-sensitized solar cell of the present invention is composed of a photoanode, a cathode, and an electrolyte layer disposed between the photoanode and the cathode.

In the dye-sensitized solar cell of the present invention, the photoanode is the photoanode described above.

In addition, the negative electrode material for the dye-sensitized solar cell is not particularly limited and may include any conductive material. On the other hand, as long as there is a conductive layer formed on the surface of the cathode facing the photoanode, the negative electrode material may be a heat resistant material. Any material with electrochemical stability can be used as the negative electrode material. Suitable examples of the negative electrode material include, but are not limited to, Pt, Au, C, and the like.

Furthermore, the material used in the electrolyte layer of the dye-sensitized solar cell is not particularly limited, and any material may be used as long as the material can transfer electrons and / or holes.

On the other hand, the present invention also provides a method for producing a dye-sensitized solar cell consisting of the following steps:

(1) providing the aforementioned photoanode; (2) providing a second substrate; (3) forming a metal layer on the second substrate; (4) configuring the photoanode and the second substrate such that a semiconductive layer faces the metal layer and a space portion is formed between the photoanode and the second substrate; (5) filling an electrolyte in the space part; And (6) sealing the space part.

The dye-sensitized solar cell of the present invention has excellent photoelectric properties and photoelectric conversion efficiency.

The organic sensitizer represented by the following general formula (I) of the present invention may be synthesized according to Scheme 1 below.

[Scheme 1]

(i) KOtBu Of K ₂ CO ₃ , 1,4-dioxane) / DMF .

( ii ) PdCl ₂ ( dppf ), 5- Formyl 2-thiophenboronic acid (5- formyl -2- thiopheneboronic  acid) or 4- Formylphenylboronic acid (4- formylphenylboronic acid ), K ₂ CO ₃ , CH ₃ OH Toluene.

( iii ) Cyanoacetic acid ( cyanoacetic acid ), Piperidine ( piperidine ), CH ₃ CN .

As shown in Scheme 1, 7-bromo -9 H - fluoren-2-ylamine (7-bromo-9 H -fluoren -2-ylamine) is reacted with 1-butane iodide (1-iodobutane) (7-bromo-9,9-dibutyl -9 H-fluoren-2-yl) dibutylamine ((7-bromo-9,9- dibutyl-9 H -fluoren-2-yl) -dibutylamine (21). Then, the Suzuki coupling reaction (7-bromo-9,9-dibutyl -9 H-fluoren-2-yl) dibutylamine 21 and the 5-formyl-2-thiophene boronic acid the reaction is carried out with the reaction of 5- (9,9-dibutyl-7-dibutyl-amino -9 H-fluoren-2-yl) thiophene-2-carbaldehyde (5- (9,9-dibutyl -7-dibutylamino-9 H -fluoren-2-yl) -thiophene-2-carbaldehyde) (22a). Finally, in acetonitrile, 5- (9,9-dibutyl-7-dibutylamino-9 H -fluoren-2-yl) -thiophene-2-carbaldehyde (22a) is combined with cyanoacetic acid. Reacted with piperidine as a catalyst, and 2-cyano-3- [5- (9,9-dibutyl-7-dibutylamino-9 H -fluoren-2-yl) -cy 2-yl] -acrylic acid (2-cyano-3- [5- (9,9-dibutyl-7-dibutylamino-9 H -fluoren-2-yl) -thiophen-2-yl] -acrylic acid) ( To produce I-1).

Organic dyes represented by the formulas (II-1) and (II-2) are commercially available.

The method for producing the dye-sensitized solar cell of the present invention is not particularly limited, and the dye-sensitized solar cell of the present invention may be manufactured by a typical method well known in the art.

The material of the transparent substrate is not particularly limited as long as the material of the substrate is a transparent material. Preferably, the material of the transparent substrate is a transparent material having good moisture resistance, solvent resistance and weather resistance. Therefore, dye-sensitized solar cells can withstand external moisture or gases due to the transparent substrate. Specific examples of transparent substrates include transparent inorganic substrates such as quartz and glass; Transparent plastic substrates such as polyethylene terephthalate (PET), polyethylene 2,6-naphthalate (PEN), polycarbonate (PC), polyethylene (PE), polypropylene (PP), and polyimide (PI), It is not limited to this.

In addition, the thickness of the transparent substrate is not particularly limited and may vary depending on the requirements regarding the transmittance and the characteristics of the dye-sensitized solar cell. In a particular embodiment of the invention, the material of the transparent substrate is a glass substrate.

Furthermore, the material of the transparent conductive layer may be indium tin oxide (ITO), fluorinated tin oxide (FTO), ZnO-Ga ₂ O ₃ , ZnO-Al ₂ O ₃ or tin oxide.

In certain embodiments of the invention, fluorinated tin oxide (FTO) is used in the transparent conductive layer.

In addition, the porous semiconducting layer can be composed of semiconductor particles. Suitable semiconductor materials may include Si, TiO ₂ , SnO ₂ , ZnO, WO ₃ , Nb ₂ O ₅ , TiSrO _3, or mixtures thereof. First, the semiconductor particles are made in paste form, and then the transparent conductive substrate is coated with the paste. The coding process used in the present invention is blade coating, screen printing, spin coating, spray coating, or wet coating. In addition, the coating can be carried out once or several times to yield a porous semiconducting layer with an appropriate thickness. The semiconducting layer may consist of a single layer or multiple layers, in which case each layer is formed of semiconductor particles having a different diameter. For example, semiconductor particles having a diameter of 5 to 50 nm are coated to a thickness of 5 to 20 μm, and then semiconductor particles having a diameter of 200 to 400 nm are coated to a thickness of 3 to 5 μm. After the coated substrate is dried at 50-100 ° C., the coated substrate is sintered at 400-500 ° C. for 30 minutes to produce a multilayer semiconducting layer.

The organodyes can be dissolved in a suitable solvent to prepare a dye solution. Suitable solvents include, but are not limited to, acetonitrile, methanol, ethanol, propanol, butanol, dimethyl formamide, N-methyl-2-pyrrolidinone or mixtures thereof. In this specification, the transparent substrate coated with the semiconducting layer absorbs the dye such that the semiconducting layer absorbs the dye completely on the dye solution. After dye absorption is completed, the transparent substrate coated with the semiconducting layer is taken out and dried to form a photoanode for a dye-sensitized solar cell.

In addition, the negative electrode material for dye-sensitized solar cells is not particularly limited and may include any conductive material. On the other hand, the material of the cathode may be a heat resistant material as long as there is a conductive layer formed on the surface of the cathode facing the photoanode. The negative electrode material may be a material having electrochemical stability. Examples of suitable negative electrode materials include, but are not limited to, Pt, Au, C, and the like.

Furthermore, the material used in the electrolyte layer of the dye-sensitized solar cell is not particularly limited and may be any material capable of transporting electrons and / or holes. In addition, the liquid electrolyte may be acetonitrile solution containing iodine, N-methyl-2-pyrrolidinone solution containing iodine or 3-methoxy propionitrile containing iodine ( 3-methoxy propionitrile) solution. In certain embodiments of the invention, the solution electrolyte may be an acetonitrile solution comprising iodine.

One specific embodiment of the method of manufacturing the dye-sensitized solar cell of the present invention is as follows.

First, a glass substrate covered with fluorinated tin oxide (FTO) is coated by screen printing once or several times with a paste made of TiO ₂ particles having a diameter of 20 to 30 nm. The coated glass substrate is then sintered at 450 ° C. for 30 minutes.

The organodyes are dissolved in a mixture of acetonitrile and t-butanol in a volume ratio of 1: 1 to form a dye solution. Then, the organic substrate having the porous TiO ₂ layer described above is allowed to be absorbed into the dye solution. After the porous TiO ₂ layer absorbs the organic sensitizer in the dye solution, the resulting organic substrate is taken out and dried to form a photoanode.

Holes are made to create a 0.75 μm diameter inlet for injecting electrolyte into a glass substrate covered with fluorinated tin oxide. Then, a glass substrate covered with fluorinated tin oxide is coated with a solution of H ₂ PtCl ₆ , and the glass substrate is heated at 400 ° C. for 15 minutes to form a cathode.

In turn, a thermoplastic polymer layer having a thickness of 60 μm is located between the photoanode and the cathode. By applying pressure to the two electrodes at 120 to 140 ° C, both electrodes are attached to each other.

The electrolyte is then injected and the electrolyte injected is an acetonitrile solution comprising 0.03 M I2 / 0.3 M LiI / 0.5 M t-butyl-pyridine. After the inlet is sealed with the thermoplastic polymer layer, the dye-sensitized solar cell of the present invention is made.

The following examples are given for the purpose of illustrating the invention. However, the scope of the present invention should be defined by the claims of the present specification, and the following examples should not be understood in any way as limiting the scope of the present invention. In the examples which follow, the compounds are shown in the form of free acids but the actual form of the sensitizing dye may be a salt, possibly an alkali metal salt or a quaternary ammonium salt. Additionally, unless otherwise specified, the weight units used in the examples are parts by weight and weight percent, and the temperature is degrees Celsius (° C.). The relationship between volume ratio and parts by weight is similar to that between kilograms and liters.

In the following description, a method of synthesizing an organic sensitizer and a method of manufacturing a dye-sensitized solar cell will be described in detail, and a method of synthesizing an organic sensitizer may be described in Scheme 1 described above.

Example  One

(7- Bromo -9,9- Dibutyl -9 H - Fluorene -2 days)- Of dibutylamine (21)  synthesis

Under N ₂ atmosphere, 0.52 parts by weight of 7-bromo-9 H -fluoren-2-ylamine, 2.21 parts by weight of 1-iobutane, 0.67 parts of potassium-t-butoxide, and 0.83 parts of potassium carbonate were dried. 10 parts by weight of dimethylformamide and 10 parts by weight of 1,4-dioxane are added, followed by stirring and mixing. The reaction mixture was then heated to 95 ° C. and reacted for 24 hours. After the reaction mixture had cooled down, the reaction was quenched with water, the product was extracted with diethyl ether and the dehydration process was performed with magnesium sulfate. After removal of the solvent, the residue was purified in a silica gel column using dichloromethane / hexanes as eluent to yield compound 21 of this example. The compound was in the form of a light yellow solid and the yield was 83%.

Example  2

5- (9,9- Dibutyl -7- Dibutylamino -9 H - Fluorene -2 days)- Thiophene -2- Carbaldehyde  Synthesis of 22a

0.49 parts by weight of (7-bromo-9,9-dibutyl-9 H -fluoren-2-yl) -dibutylamine (21) under N ₂ atmosphere, 5-formyl-l-2-thiophene 0.19 parts by weight of boronic acid, 0.41 part by weight of potassium carbonate and 0.16 part by weight of PdCl ₂ (dppf) were added to 5 parts by weight of toluene and 5 parts by weight of CH ₃ OH, followed by stirring and mixing. The reaction mixture was then heated to 60 ° C. and reacted for 18 hours. The reaction was quenched with water, the product was extracted with diethyl ether and dehydrated with magnesium sulfate. After solvent removal, the residue was purified in a silica gel column using dichloromethane / hexane as eluent to yield Compound 22a in this example. The compound was in the form of an orange solid with a yield of 52%.

Example  3

4- (9,9- Dibutyl -7- Dibutylamino -9 H - Fluorene -2 days)- Benzaldehyde (22b)

The method for preparing the compound of this example was the same as that described in Example 2 except that 5-formyl-2-thiophenboronic acid was replaced with 0.18 parts by weight of 4-formylphenylboronic acid to yield compound (22b). Is the same as The compound was in the form of a yellow solid, yield 61%.

Example  4

2- Cyano -3- [5- (9,9- Dibutyl -7- Dibutylamino -9 H - Fluorene -2 days)- Thiophene Synthesis of 2-yl] -acrylic acid (I-1)

Under N ₂ atmosphere, 5- (9,9-dibutyl-7-dibutyl-amino -9 H-fluoren-2-yl) thiophene-2-carbaldehyde and 0.23 parts by weight (22a), cyano-acetic acid 0.05 part by weight and 0.017 part by weight of piperidine were added to 10 parts by weight of acetonitrile, stirred and mixed. The reaction mixture was then heated to 90 ° C. and reacted for 6 hours. After the reaction mixture cooled to room temperature, the reaction mixture was filtered to give a solid. The solid was then washed successively with water, ether and acetonitrile to yield a dark red solid. Finally, the dark red solid was purified in a silica gel column using dichloromethane / methanol as eluent to yield compound (I-1) of this example. The compound was in the form of a dark red solid and the yield was 86%.

Example  5

2- Cyano -3- [4- (9,9- Dibutyl -7- Dibutylamino -9 H - Fluorene -2 days)- Phenyl Synthesis of] -acrylic acid (I-2)

Process for preparing a compound of this embodiment is 5- (9,9-dibutyl-7-dibutyl-amino -9 H-fluoren-2-yl) thiophene-2-carbaldehyde (22a) The 4- (9,9-dibutyl-7-dibutyl-amino -9 H-fluoren-2-yl) - are the same as described in the example 4 except that the substituted benzaldehyde (22b). The compound was in the form of an orange solid, with a yield of 68%.

Comparative Example  1 to 10

Manufacture of Dye-Sensitized Solar Cell

Glass substrates covered with fluorinated tin oxide (FTO) were coated one or several times with a paste comprising TiO ₂ particles having a diameter of 20-30 nm. The thickness of the glass substrate is 4 mm, and the electrical resistance of the glass substrate is 10 Ω. The coated glass substrate was then sintered at 450 ° C. for 30 minutes, and the thickness of the sintered porous TiO ₂ layer was 10-12 μm.

The second organodyes of formula (II-1) and (II-2) were prepared at concentrations of 1 × 10 ⁻⁴ M, and the first organodyes of formulas (I-1) and (I-2) were 5 Prepared at × 10 ^-4 M concentration. Then, the anode coated with the TiO ₂ layer was added to the dye solutions of the formulas (I-1), (I-2), (II-1), and (II-2) for 2, 5, 7, and 24 hours, respectively. To be absorbed. The absorption conditions are shown in Table 1 below.

Holes are made to create a 0.75 μm diameter inlet for injecting electrolyte into a glass substrate covered with fluorinated tin oxide. Then, a glass substrate covered with fluorinated tin oxide was coated with a solution of H ₂ PtCl ₆ (2 mg Pt in 1 ml ethanol), and the resulting glass substrate was heated at 400 ° C. for 15 minutes to form a cathode. .

In turn, a thermoplastic polymer layer having a thickness of 60 μm is located between the photoanode and the cathode. By applying pressure to the two electrodes at 120 to 140 ° C, both electrodes are attached to each other.

The electrolyte is then injected and the electrolyte injected is an acetonitrile solution comprising 0.03 M I2 / 0.3 M LiI / 0.5 M t-butyl-pyridine. After the inlet is sealed with the thermoplastic polymer layer, the dye-sensitized solar cell of this comparative example is made.

Hour Organic dyes Comparative Example 1 2 h Ⅰ-2 Comparative Example 2 5 h Ⅰ-2 Comparative Example 3 8 h Ⅰ-2 Comparative Example 4 24 h Ⅰ-2 Comparative Example 5 8 h Ⅰ-1 Comparative Example 6 2 h II-2 Comparative Example 7 5 h II-2 Comparative Example 8 8 h II-2 Comparative Example 9 24 h II-2 Comparative Example 10 8 h II-1

Example  6-12

Manufacture of Dye-Sensitized Solar Cell

Glass substrates covered with fluorinated tin oxide (FTO) were coated one or several times with a paste comprising TiO ₂ particles having a diameter of 20-30 nm. The thickness of the glass substrate is 4 mm, and the electrical resistance of the glass substrate is 10 Ω. The coated glass substrate was then sintered at 450 ° C. for 30 minutes, and the thickness of the sintered porous TiO ₂ layer was 10-12 μm.

Subsequently, the co-absorption method was performed using two types of organosensitivity dyes. First, the second organosensitivity dyes of formulas (II-1) and (II-2) were prepared at concentrations of 1 × 10 ⁻⁴ M and the first organosensitizers of formulas (I-1) and (I-2) Dyes were prepared at a concentration of 5 × 10 ⁻⁴ M. Then, the anode coated with the TiO ₂ layer was allowed to be absorbed in the dye solution of the second organic sensitizer for 4 hours and then absorbed into the dye solution of the first organic sensitizer for 1, 2, 4 and 6 hours. . The absorption conditions are shown in Table 2 below.

Holes are made to create a 0.75 μm diameter inlet to inject electrolyte into the glass substrate covered with fluorinated tin oxide. Then, a glass substrate covered with fluorinated tin oxide was coated with a solution of H ₂ PtCl ₆ (2 mg Pt in 1 ml ethanol), and the resulting glass substrate was heated at 400 ° C. for 15 minutes to form a cathode. .

In turn, a thermoplastic polymer layer having a thickness of 60 μm is located between the photoanode and the cathode. By applying pressure to the two electrodes at 120 to 140 ° C, both electrodes are attached to each other.

The electrolyte is then injected and the electrolyte injected is an acetonitrile solution comprising 0.03 M I2 / 0.3 M LiI / 0.5 M t-butyl-pyridine. After the inlet is sealed with the thermoplastic polymer layer, the dye-sensitized solar cell of this embodiment is made.

Hour Second
Organic dyes Hour 1st
Organic dyes Example 6 4 h II-2 1 h Ⅰ-2 Example 7 4 h II-2 2 h Ⅰ-2 Example 8 4 h II-2 4 h Ⅰ-2 Example 9 4 h II-2 6 h Ⅰ-2 Example 10 4 h II-2 4 h Ⅰ-1 Example 11 4 h II-1 4 h Ⅰ-1 Example 12 4 h II-1 4 h Ⅰ-2

Experiment method and result

UV - Vis  spectrum

Organosensitive dyes of formula (I-1), (I-2), (II-1), and (II-2) were prepared using methylene chloride as a solvent to produce a dye solution. Then, the UV-Vis spectrum of each dye solution was measured.

The λmax of the organic sensitizer of formula (I-1) is 427 nm, the λmax of the organic sensitizer of formula (I-2) is 380 nm, and the λmax of the organic sensitizer of formula (II-1) is 491 nm. , Λmax of the organic sensitizer represented by formula (II-2) is 526 nm.

Experiment on Optoelectronic Characteristics

Short Circuit Current (JSC), Open Circuit Voltage (VOC), Fill Factor (FF), and Photoelectric Conversion Efficiency (η) of Dye-Sensitized Solar Cells Made by Comparative Examples 1-4, 6-9, and Example 6-9 Was measured under the illumination of AM 1.5 photostimulation. Experimental results are shown in Tables 3 and 4 below.

Experimental Result of Dye-Sensitized Solar Cell J _sc (mA / cm ² ) V _oc (V) FF η (%) Comparative Example 11 7.51 0.68 0.62 3.23 Comparative Example 2 7.54 0.68 0.61 3.11 Comparative Example 3 5.46 0.63 0.64 2.20 Comparative Example 4 5.64 0.67 0.61 2.24 Comparative Example 6 11.10 0.67 0.55 4.09 Comparative Example 7 11.33 0.66 0.57 4.30 Comparative Example 8 10.61 0.65 0.53 3.67 Comparative Example 9 9.93 0.65 0.56 3.67 Example 6 11.70 0.70 0.58 4.80 Example 7 11.96 0.69 0.59 4.86 Example 8 11.93 0.70 0.59 5.00 Example 9 12.81 0.70 0.61 5.56

According to the experimental results of Table 3, the optoelectronics of the dye-sensitized solar cell (Example 6-9) manufactured using a joint absorption method using both the first organic dye (a) and the second organic dye (b) The characteristic is when only the first organic dye (a) is used (for example, Comparative Example 1-4) or when only the second organic dye (b) is used (for example, Comparative Example 6-9 Better than manufactured by).

Experimental Result of Dye-Sensitized Solar Cell J _sc (mA / cm ² ) V _oc (V) FF η (%) Comparative Example 3 5.46 0.63 0.64 2.20 Comparative Example 5 8.15 0.68 0.64 3.55 Comparative Example 8 10.61 0.65 0.53 3.67 Comparative Example 10 6.76 0.64 0.60 2.65 Example 8 11.93 0.70 0.59 5.00 Example 10 10.62 0.69 0.65 4.75 Example 11 9.34 0.66 0.62 3.81 Example 12 9.85 0.73 0.66 4.80

According to the experimental results of Table 4, both the first organic sensitizer (formula (I-1) and (I-2)) and the second organic sensitizer (formula (II-1) and (II-2)) were used The optoelectronic characteristic of the dye-sensitized solar cells (Examples 8, 10 and 11) manufactured using the joint absorption method is that only the first organic dye (a) is used (for example, Comparative Example 3-5). Or better than that prepared in the case where only the second organic sensitizer (b) is used (eg, Comparative Example 8-10).

In other words, since the structure of the first organic dye and the structure of the second organic dye are different from each other, the maximum absorption wavelength between the first organic dye and the second organic dye is different in the UV-vis spectrum. Therefore, when two organic sensitizers having different absorption wavelengths are co-absorbed to produce a dye-sensitized solar cell, the spectrum utilization in the visible region increases. In addition, the method of performing the joint absorption method can be adjusted according to the type of organic sensitizer, and the photoelectric efficiency of the solar cell is increased.

In conclusion, the present invention differs from the prior art in various respects such as purpose, method, efficiency, or even technology, research and design. Although the present invention has been described in connection with preferred embodiments of the invention, many other possible modifications and variations are possible without departing from the scope of the invention as claimed below. Therefore, the scope of the present invention should be defined by the claims of the present specification, and the above-mentioned embodiments should not be understood in any way as limiting the scope of the present invention.

Claims (18)

A photoanode which is a substrate comprising (a) a first organosensitive dye or salt thereof and (b) a semiconductive layer absorbing the second organosensitive dye, which is configured as follows:
(a) the first organic sensitizer represented by the following general formula (I) or salts thereof,
<Formula (I)>

In the above formula (I),
R ₁ , R ₂ , R ₃ , and R ₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, n is an integer of 1, 2, or 3;
D ₁ and D ₂ are each independently C ₁ -C ₁₂ alkyl,

,

,

or

Or D ₁ , D ₂ , and N bonds together

,

or

R ₅ , R ₆ , R ₇ , R ₈ , R ₁₀ , R ₁₁ , R ₁₃ , and R ₁₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, amino , Or halogen, and R ₉ , R ₁₂ and R ₁₅ are each independently H or C ₁ -C ₁₂ alkyl;
B is

,

,

,

,

,

or

R ₁₆ , R ₁₇ and R ₁₈ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or halogen, and R ₁₉ , R ₂₀ , R ₂₁ and R ₂₂ are each independently H Or C ₁ -C ₁₂ alkyl, Z is O, S, or Se; And
(b) The second organic sensitizing dye having a difference in maximum absorption wavelength from the first organic sensitizing dye (a) of 50 nm or more.
The photoanode according to claim 1, wherein n is one.
The method of claim 1, wherein D ₁ and D ₂ are each independently C ₁ ~ C ₁₂ alkyl,

or

R ₅ , R ₆ , R ₇ and R ₈ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, amino, or halogen, and R ₉ is H, or C ₁ -C Photoanode, characterized in that ₁₂ alkyl.
The method of claim 3, wherein B is

,

or

R ₁₆ is H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or halogen, R ₁₉ and R ₂₂ are each independently H or C ₁ -C ₁₂ alkyl, and Z is O, S or Photoanode, characterized in that the Se.
5. The photoanode according to claim 4, wherein Z is S and n is 1.
The method according to claim 5, wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ and R ₁₆ are each independently H, C ₁ ~ C ₁₂ alkyl, or C ₁ ~ _C12 alkoxy. Photoanode.
The method according to claim 6, wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ and R ₁₆ are each independently H or C ₁ ~ C ₁₂ alkyl, characterized in that Photoanode.
The method of claim 1, wherein B is

or

R ₁₆ is H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or halogen, R ₁₉ is H or C ₁ -C ₁₂ alkyl, Z is O, S, or Se Photoanode to say.
The method according to claim 8, wherein D ₁ and D ₂ are each independently C ₁ ~ C ₁₂ alkyl, or

R ₅ , R ₆ , and R ₇ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ Photoanode, characterized in that alkoxy, amino or halogen.
10. The photoanode according to claim 9, wherein Z is S and n is 1.
The method according to claim 10, wherein R ₁ , R ₂ , R ₃ , R _{4 ,} R ₅ , R ₆ , R ₇ And R ₁₆ are each independently H, C ₁ -C ₁₂ alkyl, or C ₁ -C ₁₂ Photoanode, characterized in that alkoxy.
The method according to claim 11, wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ And R ₁₆ are each independently H, or C ₁ to C ₁₂ alkyl.
13. The photoanode according to claim 12, wherein R ₁₆ and R ₁₉ are H.
The photoanode according to claim 1, wherein the first organosensitive dye (a) is a compound represented by the following general formula (I-1) or (I-2) or a salt thereof:

(I-1)

(I-2). The photoanode according to claim 1, wherein the second organosensitive dye (b) is a compound represented by the following general formula (II-1) or (II-2) or a salt thereof:

(II-1)

(II-2).
The photoanode according to claim 14, wherein the second organic sensitizer (b) is a compound represented by the formula (II-1) or (II-2) or a salt thereof.
(A) A photoanode, which is a substrate comprising a semiconducting layer that absorbs dye, wherein the dye is constructed as follows:
(a) the first organic sensitizing agent represented by the following general formula (I), or salts thereof,
<Formula (I)>

In the above formula (I),
R ₁ , R ₂ , R ₃ , and R ₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, or halogen, n is an integer of 1, 2, or 3;
D ₁ , and D ₂ are each independently C ₁ -C ₁₂ alkyl,

,

,

or

Or D ₁ , D ₂ , and N bonds together

,

or

Form R ₅ , R ₆ , R ₇ , R ₈ , R ₁₀ , R ₁₁ , R ₁₃ and R ₁₄ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy, amino, Or halogen, R ₉ , R ₁₂ and R ₁₅ are each independently H or C ₁ -C ₁₂ alkyl;
B is

,

,

,

,

,

or

R ₁₆ , R ₁₇ and R ₁₈ are each independently H, C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or halogen, and R ₁₉ , R ₂₀ , R ₂₁ and R ₂₂ are each independently H Or C ₁ -C ₁₂ alkyl, Z is O, S or Se; And
(b) a second organic sensitizing dye having a difference in maximum absorption wavelength between the first organic sensitizing dye and the second organic sensitizing dye of 50 nm or more;
(B) a negative electrode; And
(C) an electrolyte layer disposed between the photoanode and the cathode;
Dye-sensitized solar cell comprising a.
Method for producing a dye-sensitized solar cell consisting of the following steps:
A. providing the photoanode of claim 1;
B. providing a second substrate;
C. forming a metal layer over the second substrate;
D. constructing the photoanode and the second substrate so that a semiconductive layer faces the metal layer and a space is formed between the photoanode and the second substrate;
E. Filling an electrolyte in the space; And
F. Sealing the space part.