KR101117426B1 - Organic solar cell and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an organic solar cell and a method for manufacturing the same. Specifically, the organic solar cell of the present invention comprises a first electrode; Second electrode; And a photoelectric conversion layer disposed between the first electrode and the second electrode, wherein the photoelectric conversion layer comprises a light absorption layer; And an organic layer containing a phosphine derivative compound formed between the light absorption layer and the second electrode.
The solar cell of the present invention is not only excellent in thermal stability and increased in efficiency, but also easily manufactured by a solution process rather than a deposition process.

Description

Organic solar cell and manufacturing method thereof

The present invention relates to an organic solar cell and a method for manufacturing the same, and more particularly, to an organic solar cell and a method for manufacturing the same, which can be easily manufactured by a solution process instead of an excellent thermal stability and efficiency.

Organic solar cells are expected to be manufactured in the future as low-cost solar cells because they can be manufactured with a simple manufacturing method and low equipment cost compared with conventional silicon or compound semiconductor solar cells.

In the organic solar cell, many materials and structures have been studied to improve the efficiency of the solar cell, but among them, a bulk heterojunction using a mixture of an electron acceptor and an electron acceptor is used. heterojunction) structure is known to have the highest efficiency.

However, the bulk heterojunction structure has an electron donor and electron acceptor within this distance because the diffusion distance between electrons formed in electron donors such as conductive polymers by solar light and exciton, an electron pair, is only about 10 nm in the polymer. If the interface does not reach the problem of recombination and extinction again. In addition, after the electron and hole are separated from the electron donor and the electron acceptor, the electron and the hole move toward the metal electrode and the transparent electrode, so that all electron donors are connected while having a co-continuous structure. It should be in contact with the negative electrode, and all electron receivers should be connected and in contact with the positive electrode. However, the structure of the electron donor and electron receiver cannot be determined artificially, but depends on the phase separation property after mixing the material. Can't get it.

In addition, electron transfer to a metal electrode such as Al or Ag, which is generally used as an electrode, causes a lot of loss due to poor interface characteristics between the light absorption layer and the electrode. Therefore, the short-circuit current and the open voltage of the organic solar cell are lowered, thereby reducing the efficiency of the organic solar cell. As a method for improving such interfacial properties, spiro compounds, fullerene-based compounds, or ionic bonding compounds such as LiF have been applied, but the effect of improving the interfacial properties is insignificant, and is applicable only to the deposition process at a high temperature. There is a problem that is difficult to apply to the process.

An object of the present invention to solve the above problems is to provide an organic solar cell and a method for manufacturing the same, which can be easily manufactured by a solution process rather than a deposition process with excellent thermal stability and efficiency.

The present invention to achieve the above object,

A first electrode; A second electrode; And a photoelectric conversion layer disposed between the first electrode and the second electrode,

The photoelectric conversion layer is a light absorption layer; And it provides an organic solar cell comprising an organic layer containing a phosphine derivative compound formed between the light absorption layer and the second electrode.

The phosphine derivative compound may be represented by the following Chemical Formula 1 or the following Chemical Formula 2:

<Formula 1>

<Formula 2>

(Formula 1 and 2,

Y ₁ and Y ₂ are each independently oxygen, sulfur or selenium,

Ar ₁ to Ar ₆ are each independently a substituted or unsubstituted aryl group having 6 to 50 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms, and the substitution is a halogen atom, cyano group, nitro group, It consists of an aryl group having 6 to 50 carbon atoms, a heteroaryl group having 5 to 50 carbon atoms, an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group having 3 to 50 carbon atoms, a thio group having 1 to 50 carbon atoms, and a silyl group having 1 to 50 carbon atoms. ,

Ar is selected from the following structural formulas 1 to 4;

<Structure 1>

<Formula 2>

<Structure 3>

<Structure 4>

In structures 1 to 4,

Each X is independently a carbon, silicon, germanium, phosphorus or sulfur atom,

R ₁ to R ₂₀ are each independently hydrogen, halogen atom, cyano, nitro, substituted or unsubstituted aryl group having 6 to 50 carbon atoms, substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms, substituted or unsubstituted Substituted alkyl group having 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 50 carbon atoms, substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, substituted or unsubstituted alkynyl group having 1 to 50 carbon atoms, substituted or unsubstituted A substituted C1-C50 silyl group, a substituted or unsubstituted C1-C50 amino group, or a substituted or unsubstituted C1-C50 boraneyl group, wherein R ₁ to R ₂₀ are each independently or together with an adjacent group Can form saturated or unsaturated rings,

m1 to m4, m6 to m9, m12 to m14 and m17 to m20 are each independently an integer of 1 to 4, m5 is 1 or 2, m10, m11 and m15 are each independently an integer of 1 to 3, m16 Is 1,

n is an integer of 0 to 4).

The organic layer may be formed by coating and drying a coating composition including the phosphine oxide derivative and a polar solvent on an upper surface of the light absorbing layer.

The organic layer may be formed to 1 to 30 nm.

The present invention to achieve another object of the present invention,

It provides a method for manufacturing an organic solar cell comprising the step of applying an organic layer forming the coating composition comprising a phosphine derivative compound represented by the formula 1 or 2 and a polar solvent on the upper surface of the light absorption layer and dried.

The polar solvent is a ketone selected from the group consisting of alcohol solvents selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, glycerol, propylene glycol and 1,3-butylene glycol, acetone, butanone and penta Cyclic ether solvent selected from the group consisting of dioxane and tetrahydrofuran, ester solvents selected from the group consisting of solvents, ethyl acetate and butyl acetate, acetonitrile, dimethylformamide and dimethyl sulfoxide Alone or mixtures thereof.

The organic solar cell of the present invention not only has excellent high temperature stability including an organic layer containing a phosphine derivative compound, but also has a high efficiency due to an increase in a short circuit current and an open voltage.

In addition, the organic solar cell of the present invention can be easily manufactured in a simple process by forming a thin film through a solution process.

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

Hereinafter, the present invention will be described in detail so that those skilled in the art can easily practice.

1 is a cross-sectional view showing an organic solar cell 100 according to an embodiment of the present invention. Referring to FIG. 1, the organic solar cell 100 of the present invention includes a first electrode 110; Second electrode 120; And a photoelectric conversion layer 130, wherein the photoelectric conversion layer 130 includes a hole transport layer 131; Light absorption layer 132; And an organic layer 133.

The organic solar cell of the present invention is excellent in solar cell efficiency and high temperature stability due to the organic layer 133.

The organic layer includes a phosphine derivative compound.

The phosphine derivative compound has a characteristic of strongly attracting electrons to form a dipole. As a result, the phosphine derivative compound changes the energy level of the metal by forming a dipole and a dipole when contacted with the metal electrode, and changes the work function toward the vacuum energy level when contacted with a metal such as Al, Ag, or Au. Do it. As a result, the energy barrier of the electrode interface is reduced, thereby inducing ohmic contact in electron transfer with a compound generally applied as an electron acceptor, and inducing an increase in a short circuit current and an open voltage. Therefore, the efficiency of the organic solar cell is increased.

The phosphine derivative compound may preferably be represented by the following formula (1) or (2):

<Formula 1>

<Formula 2>

In Chemical Formulas 1 and 2, Y ₁ To Y ₃ Are each independently selected from oxygen, sulfur or selenium, preferably oxygen. Y ₁ To Y ₃ When oxygen is the largest increase in the short-circuit current and open voltage is the highest efficiency of the organic solar cell of the present invention. Ar ₁ to Ar ₆ are each independently a substituted or unsubstituted aryl group having 6 to 50 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms, wherein the substitution is a halogen atom or a cyano group , A nitro group, an aryl group having 6 to 50 carbon atoms, a heteroaryl group having 5 to 50 carbon atoms, an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group having 3 to 50 carbon atoms, a thio group having 1 to 50 carbon atoms, and having 1 to 50 carbon atoms Can be made by silyl.

Ar may be selected from the following Structural Formulas 1-4:

<Structure 1>

<Formula 2>

<Structure 3>

<Structure 4>

In Formulas 1 to 4, each X may be independently selected from carbon, silicon, germanium, phosphorus, or sulfur atoms. R ₁ to R ₂₀ may be the same as or different from each other, and each independently hydrogen, a halogen atom, cyano, nitro, a substituted or unsubstituted aryl group having 6 to 50 carbon atoms, a substituted or unsubstituted carbon number 5 to 50 Heteroaryl group, substituted or unsubstituted C1-C50 alkyl group, substituted or unsubstituted C3-C50 cycloalkyl group, substituted or unsubstituted C2-C50 alkenyl group, substituted or unsubstituted C1 It may be selected from an alkynyl group of 50 to 50, a substituted or unsubstituted silyl group having 1 to 50 carbon atoms, a substituted or unsubstituted amino group having 1 to 50 carbon atoms or a substituted or unsubstituted boraneyl group having 1 to 50 carbon atoms, and R ₁ to R ₂₀ may each independently form a saturated or unsaturated ring with or adjacent groups. In this case, the 'substituted' is a halogen atom, cyano group, nitro group, aryl group having 6 to 50 carbon atoms, heteroaryl group having 5 to 50 carbon atoms, alkyl group having 1 to 50 carbon atoms, cycloalkyl group having 3 to 50 carbon atoms, carbon number It can be made from 1 to 50 thio groups, silyl groups having 1 to 50 carbon atoms. M1 to m4, m6 to m9, m12 to m14, and m17 to m20 are each independently an integer of 1 to 4, m5 is 1 or 2, m10, m11 and m15 are each independently an integer of 1 to 3, m16 is 1; N may be an integer of 0 to 4.

Ar ₁ to Ar ₆ in Formula 1 or 2 And the substituted or unsubstituted aryl group having 6 to 50 carbon atoms at R ₁ to R _{20 may be} specifically, a phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, and 9-an Trinyl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group, 1-naphthacenyl group, 2-naphthacenyl group, 9-naphthacenyl group , 1-pyrenyl group, 2-pyrenyl group, 4-pyrenyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, p-terphenyl-4-yl group, p-terphenyl-3- Diary, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-tolyl group, m-tolyl group, p- Tolyl group, p-tert-butylphenyl group, p- (2-phenylpropyl) phenyl group, 3-methyl-2-naphthyl group, 4-methyl-1-naphthyl group, 4-methyl-1-anthryl group, 4- Methyl biphenylyl group, 4-tert- butyl- p-terphenyl-4-yl group, etc. are mentioned. Specific examples of the substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms include pyrrolyl, pyrazinyl, pyrimidyl, pyridazyl, pyridinyl, indolyl, benzofuranyl, quinolyl and quinox Salineyl group, phenanthridineyl group, phenanthrolineyl group, an oxazolyl group, a pyrrole group, etc. are mentioned. Specific examples of the substituted or unsubstituted alkyl group having 1 to 50 carbon atoms include methyl, ethyl, butyl, hexyl, heptyl, hydroxymethyl, ethyl halide, methyl halide, cyanomethyl group, cyanoethyl group, cyclopropyl group, nitro Methyl group, amandanyl group, a norbornyl group, etc. are mentioned. Specific examples of the substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms include ethenyl, propenyl, butenyl, pentenyl, hexenyl, 2-methyl-ethenyl, 2-methyl-propenyl and 2-methyl -Butenyl, 2-methyl-pentenyl, 2-methyl-hexenyl group, etc. are mentioned. As a specific example of the said C1-C50 alkynyl group, 2-methylethynyl, 2-methylpropynyl, 2-methylbutynyl, 3-methoxyheptinyl group, etc. are mentioned. Specific examples of the substituted or unsubstituted amino group having 1 to 50 carbon atoms include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, isopropylamine, isobutylamine, tert-butylamine , 2-pentylamine, neo-pentylamine, phenylamine, naphthylamine, biphenylamine, anthracenylamine, 3-methyl-phenylamine, 4-methyl-naphthylamine, 2-methyl-biphenylamine or 9 -Methyl-anthracenylamine, phenylmethylamine, phenylethylamine, naphthylmethylamine, naphthylethylamine, biphenylmethylamine, 3-methyl-phenylmethylamine, phenyl (isopropyl) amine, naphthyl (isopropyl ) Amine, naphthyl (isobutyl) amine, biphenyl (isopropyl) amine group, etc. are mentioned. Specific examples of the substituted or unsubstituted silyl group having 1 to 50 carbon atoms include trimethylsilyl, triethylsilyl, tributylsilyl, tri (isopropyl) silyl, tri (isobutyl) silyl, tri (tert-butyl) silyl , Tri (2-butyl) silyl, triphenylsilyl, trinaphthylsilyl, tribiphenylsilyl, tri (3-methylphenyl) silyl, tri (4-methylnaphthyl) silyl, tri (2-methylbiphenyl) silyl , Phenylmethylsilyl, phenylethylsilyl, naphthylmethylsilyl, naphthylethylsilyl, biphenylmethylsilyl, 3-methyl-phenylmethylsilyl, phenyl (isopropyl) silyl, naphthyl (isopropyl) silyl or biphenyl ( Isopropyl) silyl group etc. are mentioned.

Preferably, in Formula 1 or 2, Y ₁ to Y ₃ are oxygen, and Ar ₁ to Ar ₆ are each independently a substituted or unsubstituted phenyl group having 6 to 34 carbon atoms, a substituted or unsubstituted biphenyl group, substituted or It may be an unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthryl group, or a substituted or unsubstituted pyrenyl group.

Specific examples of the phosphine derivative compounds represented by Formula 1 or 2 used in the organic layer 133 of the present invention are illustrated in Table 1 below, but are not limited thereto.

constitutional formula constitutional formula

(1)

(One)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

10

(11)

(12)

(13)

(14)

(15)

(16)

(17)

(18)

(19)

20

(21)

(22)

(23)

(24)

(25)

(26)

(27)

(28)

(29)

(30)

(31)

(32)

(33)

(34)

The organic layer 133 may be stacked between the light absorbing layer 132 and the second electrode 120, that is, on the top surface of the light absorbing layer 132 by a method commonly used in the art. When formed by a method such as vacuum deposition, there is an advantage that the deposition process may be performed at a temperature lower than 600 ° C. or higher, specifically 150 to 400 ° C., which is conventionally used.

Preferably, the organic layer 133 may be formed by coating and drying a coating composition including the phosphine derivative compound and a polar solvent on the upper surface of the light absorbing layer. That is, the organic layer 133 may be formed by a simpler, easier and environmentally friendly solution process than the deposition process, and a homogeneous thin film having little pinholes may be easily obtained.

Since the phosphine derivative compound represented by Chemical Formula 1 or 2 included in the organic layer 133 may be dissolved in a polar solvent including an alcohol solvent as well as an aromatic solvent due to its strong polarity, it may be used as a solution process using a polar solvent. The organic layer 133 may be formed, and the light absorbing layer 132 has a property of dissolving in an aromatic solvent, so that the organic layer 133 may be formed without affecting the light absorbing layer 132. Can be.

The polar solvent is an alcohol solvent such as methanol, ethanol, propanol, isopropanol, butanol, glycerol, propylene glycol and 1,3-butylene glycol, ketone solvents such as acetone, butanone, pentanone, ethyl acetate, butyl acetate Cyclic ether solvents such as ester solvents such as dioxane and tetrahydrofuran, and acetonitrile, dimethylformamide and dimethyl sulfoxide may be used alone or in a mixture thereof, but are not limited thereto. It is not. The polar solvent may be used in admixture with other polar solvents or non-polar solvents, and when mixed with other polar solvents, the ratio is not limited. However, when mixed with the non-polar solvent, the content of the polar solvent is 50 vol based on the total solvent. It is preferable that it is% or more. If the polar solvent is less than 50% by volume, the amount of the other solvent may be relatively high, which may affect the light absorbing layer.

The concentration of the compound represented by Formula 1 or 2 in the coating composition may be 0.001 to 1% by weight based on the composition. Within the above concentration range, the compound is uniformly dissolved in the solvent, thereby improving flatness and obtaining a uniform organic layer.

The coating method of the coating composition may be applied without limitation to methods known in the art such as spin coating, inkjet printing, gravure printing, slit coating, slot coating, bar coating, dip coating and the like.

The thickness of the organic layer may be 1 to 30 nm. When the organic layer is less than 1 nm, the effect of improving the interface characteristics by adjusting the energy level of the second electrode 120 may be insignificant. When it exceeds 30 nm, the efficiency of the organic solar cell is increased by increasing the resistance by the organic layer. This can be degraded.

The first electrode 110 may be a transparent electrode formed by coating a transparent electrode material on a substrate (not shown) to allow sunlight to pass therethrough. The transparent electrode material may be a metal, an alloy, an electrically conductive compound having a work function of 4 eV or more, or a mixture thereof, and specifically, a transparent oxide such as indium tin oxide (ITO), SnO ₂ , ZnO, FTO, or the like. , Organic materials such as Au, CuI, conductive polymers, graphene, graphene oxide, carbon nanotubes, or organic-inorganic coupling materials such as carbon nanotubes with metals may be used, but are not limited thereto. . The first electrode 110 may be formed to a thickness of about 10 to 300 nm. The first electrode 110 may be manufactured by forming the electrode material as a thin film through vapor deposition or sputtering such as chemical vapor deposition (CVD), physical vapor deposition (PVD), or the like.

The substrate is not shown in the drawings, but if it has good mechanical strength, thermal stability and transparency can be used without limitation conventionally used in the art, specifically, polyethylene terephthalate (PET), polyethylene naphthalate (PEN ), Polyimide, polyetheretherketone (PEEK), polyethersulfone (PES), polyetherimide (PEI), silicone, metal or glass can be used.

The second electrode 120 may be formed using a metal, an alloy, an electrically conductive compound, or a mixture thereof having a work function of less than 4 eV. Specifically, the second electrode 120 may be formed of Na, Na—K alloy, calcium, magnesium, or lithium. And lithium alloys, indium, aluminum, magnesium alloys and aluminum alloys. In addition, aluminum / AlO ₂ , aluminum / lithium, magnesium / silver or magnesium / indium and the like may also be used, and those known in the art may be used without limitation. The second electrode 120 may be formed of a conductive metal material such as aluminum, tungsten, gold, or copper by vapor deposition such as sputtering, chemical vapor deposition (CVD), or physical vapor deposition (PVD), but is not limited thereto. no. The second electrode 120 may be preferably formed to a thickness of 10 nm or more. If it is thinner than 10 nm, the resistance may increase, which may degrade the characteristics of the solar cell device.

In order to increase the efficiency of the organic solar cell, at least one electrode should preferably have a light transmittance of 10% or more. In addition, the sheet resistance of the first electrode 110 and the second electrode 120 may preferably be several hundred Ω / mm or less.

The photoelectric conversion layer 130 is a hole transport layer 131; Light absorption layer 132; And an organic layer 133.

When sunlight is incident, an exciton E (exciton) forming a pair of electrons e and holes h is formed in the light absorption layer 132, which is an interface between the light absorption layer 132 and the organic layer 133 and the light absorption layer 132. Diffusion and movement to the interface between the and the hole transport layer 131. At the interface, excitons are separated into electrons and holes, and they are transported to different electrodes to generate electromotive force.

The light absorption layer 132 may have a bulk heterojunction structure in which an electron acceptor and a hole acceptor or a hole acceptor are composed of two-layer films or are mixed with each other, and preferably, an electron acceptor and a hole acceptor. It may have a bulk heterojunction structure is mixed. Specifically, the electron acceptor may be a polymer semiconductor material such as polythiphene, polyphenylenevinylene, polyfluorene, polypyrrole, copolymers thereof, and pentacene. , An anthracene, tetratracene, perylene, oligothiphene, derivatives thereof, and the like, or a mixture thereof may be used. For example, poly-3-hexylthiophene (P3HT), poly-3-octylthiophene (P3OT), polyparaphenylene vinylene (poly-p-phenylene vinylene), PPV], poly (dioctylfluorene) [poly (9,9′-dioctylfluorene)], poly (2-methoxy, 5- (2-ethyl-hexyloxy) -1,4-phenylenevinylene) [poly (2-methoxy, 5- (2-ethyl-hexyloxy) -1,4-phenylenevinylene, MEH-PPV], poly (2-methyl, 5- (3 ', 7'-dimethyloctyloxy))-1 , 4-phenylene ratio Niylene [poly (2-methyl, 5- (3 ', 7'-dimethyloctyloxy))-1,4-phenylene vinylene, MDMOPPV] and mixtures thereof may be selected from the group consisting of, but is not limited thereto. The electron acceptor may be a fullerene or a fullerene derivative, and is preferably (6,6) -phenyl-C61-butyric acid methyl ester [(6,6) -phenyl-C61-butyric acid methyl ester; PCBM], (6,6) -phenyl-C71-butyric acid methyl ester [(6,6) -phenyl-C71-butyric acid methyl ester; C70-PCBM], fullerene (C60), (6 , 6) -thienyl-C61-butyric acid methyl ester [(6,6) -thienyl-C61-butyric acid methyl ester; ThCBM], carbon nanotubes and mixtures thereof may be selected from the group consisting of, but is not limited thereto. In order for electrons generated by light to be collected without loss to an electrode through an electron acceptor such as fullerene, the hole acceptor such as the conductive polymer and the electron acceptor must be sufficiently mixed, and the fullerene derivative such as PCBM is an electron acceptor such as fullerene. And hole acceptors such as thiophene polymers are well mixed.

The light absorbing layer 132 may be formed of the above-described material by using a known method such as vacuum deposition, spin coating or casting, and specifically, the hole transport layer may be a mixture of the hole acceptor and the electron acceptor dissolved in a solvent. 131) and can be prepared by evaporating the solvent. The solvent for dissolving the electron acceptor and the hole acceptor is preferably chloroform, benzene, toluene, chlorobenzene, dichlorobenzene, trichlorobenzene and these A mixture of may be used, but is not limited thereto.

The hole transport layer 131 is formed by applying a hole transport material to the upper portion of the first electrode 110, poly (3, 4-ethylenedioxythiophene)-polystyrene sulfonate [poly (3, 4-ethylenedioxythiophene) ) -polystyrenesulfonate, PEDOT-PSS], polyaniline, polypyrrole, copper phthalocyanine (CuPC), polyhiophenylenevinylene, polyvinylcarbazole, polyparaphenylene It can be used alone or a mixture thereof selected from the group consisting of vinylene (poly-pphenylenevinylene) and polymethylphenylsilane (poly (methylphenylsilane)), but is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. This is for the purpose of illustrating the invention only, and thus the scope of the invention is not limited.

< Example  1> Fabrication of Organic Solar Cell

Water-soluble hole transport material PEDOT-PSS was spin-coated on a conductive substrate, ITO glass substrate, and then poly-3-hexylthiophene (P3HT) and phenyl-C61-butyric acid methyl ester [ 6,6] phenyl-C61-butyric acid methyl ester (PCBM) is prepared by dissolving 1,2-dichlorobenzene, chlorobenzene, chloroform alone or 2 wt% in a mixed solvent, and mixing the respective solutions in a weight ratio of 1: 0.7. It was. The coating solution was spin-coated at 2000 rpm and dried to form an organic thin film. After the vacuum deposition of the phosphine oxide derivative of Structural Formula 1 of Table 1 on the thus formed organic thin film, an aluminum metal was deposited in the same manner to prepare an organic solar cell device.

< Example  2> Fabrication of Organic Solar Cell

An organic solar cell was manufactured in the same manner as in Example 1, except that the phosphine derivative compound was prepared in Example 1, and the solar cell was manufactured using the chemical formula 2 of Table 1.

< Example  3> Fabrication of Organic Solar Cell

An organic solar cell was manufactured in the same manner as in Example 1, except that the phosphine derivative compound was prepared in Example 1, but the solar cell was manufactured using the chemical formula 21 of Table 1.

< Example  4> Fabrication of Organic Solar Cell

An organic solar cell was manufactured in the same manner as in Example 1, except that the phosphine derivative compound was manufactured in Example 1, and the solar cell was manufactured using the chemical formula 36 of Table 1.

< Example  5> Fabrication of Organic Solar Cell

An organic solar cell was manufactured in the same manner as in Example 1, except that the phosphine derivative compound was prepared in Example 1, but the solar cell was manufactured using the chemical formula 25 of Table 1.

< Example  6> Fabrication of Organic Solar Cell Using Solution Process

PEDOT-PSS, a water-soluble hole transport material, was spin-coated on an ITO glass substrate, a conductive substrate, and then poly-3-hexylthiophene (P3HT) and phenyl-C61-butyric acid methyl ester [ 6,6] phenyl-C61-butyric acid methyl ester (PCBM) is dissolved in 1,2-dichlorobenzene, chlorobenzene, chloroform alone or 2 wt% in a mixed solvent, and the respective solutions are mixed at a weight ratio of 1: 0.7. Prepared. The coating solution was spin-coated at 2000 rpm and dried to form an organic thin film. On the organic thin film thus formed, the phosphine oxide derivatives of the structural formula 1 of Table 1 were dissolved at 0.1 wt% using isopropyl alcohol, and the coating solution was spin-coated at 2000 rpm on a light absorbing layer and dried to form an organic thin film. . An aluminum metal was vacuum deposited on the organic thin film thus formed to manufacture an organic solar cell device.

< Example  7> Fabrication of Organic Solar Cell Using Solution Process

An organic solar cell was manufactured in the same manner as in Example 6, except that the phosphine derivative compound was manufactured in Example 6, but the solar cell was manufactured using the chemical formula 2 of Table 1.

< Example  8> Fabrication of Organic Solar Cell Using Solution Process

An organic solar cell was manufactured in the same manner as in Example 6, except that the phosphine derivative compound was manufactured in Example 6 to correspond to Structural Formula 21 of Table 1 above.

< Comparative example  1> Fabrication of Organic Solar Cell

An organic solar cell was manufactured in the same manner as in Example 1, except that the LiF layer was formed instead of the organic layer including the phosphine derivative compound in Example 1.

< Comparative example  2> Fabrication of Organic Solar Cell

In the same manner as in Example 1 except for forming a Bphen (4,7-diphenyl-1,10-phenanthroline) layer having good electron transfer properties instead of the organic layer containing a phosphine derivative compound in Example 1 A solar cell was produced.

< Experimental Example  1> Measurement of solar cell efficiency

In order to evaluate the efficiency of the organic solar cells prepared in Examples and Comparative Examples, the light spectrum was adjusted using an AM 1.5G filter, and the light source reaching the sample was controlled at 1 sun condition, that is, 100 mW / cm ² . The efficiency of the solar cell measured under these standard conditions is shown in Table 2 below.

J _sc (mA / cm ² ) FF V _oc (V) Efficiency (%) Example 1 11.72 0.53 0.58 3.65 Example 2 14.60 0.43 0.59 3.75 Example 3 15.75 0.46 0.61 4.42 Example 4 11.72 0.52 0.61 3.72 Example 5 11.72 0.51 0.58 3.47 Example 6 11.8 0.52 0.59 3.62 Example 7 11.8 0.5 0.58 3.42 Example 8 11.9 0.51 0.58 3.52 Comparative Example 1 14.72 0.40 0.575 3.39 Comparative Example 2 12.30 0.44 0.38 2.11

As shown in Table 2, the organic solar cell including the organic layer containing the phosphine derivative compound of the present invention can be seen that the efficiency is increased by increasing the fill factor and the open voltage compared to the organic solar cell of the comparative example.

< Experimental Example  2> Evaluation of high temperature stability

The thermal stability of the materials constituting the solar cell by the method of measuring the efficiency by varying the temperature from room temperature to high temperature for the solar cells manufactured in Examples and Comparative Examples was shown in Table 3 below.

division Room temperature 50 ℃ 70 ℃ 90 ℃ Example 1 3.65 3.84 3.92 3.70 Example 2 3.75 3.85 3.92 3.82 Example 3 4.42 4.46 4.54 4.45 Example 4 3.72 3.85 3.89 3.86 Example 5 3.47 3.64 3.72 3.56 Example 6 3.62 3.76 3.78 3.54 Example 7 3.42 3.66 3.67 3.55 Example 8 3.52 3.64 3.54 3.46 Comparative Example 1 3.39 3.21 3.15 2.14 Comparative Example 2 2.11 2.05 2.05 2.07

As shown in Table 3, when the phosphine derivative compound of the present invention is left at a high temperature for a long time, the solar cell efficiency hardly decreases, and thus the high temperature stability is increased compared to the solar cell of the comparative example.

110: first electrode
120: second electrode
130: photoelectric conversion layer
131: hole transport layer
132: light absorption layer
133: organic layer

Claims (10)

A first electrode; Second electrode; And a photoelectric conversion layer disposed between the first electrode and the second electrode,
The photoelectric conversion layer is a light absorption layer; An organic layer containing a phosphine derivative compound represented by the following Chemical Formula 1 or the following Chemical Formula 2 formed between the light absorption layer and the second electrode; And a hole transport layer formed between the first electrode and the light absorption layer.
<Formula 1>

<Formula 2>

(Formula 1 and 2,
Y ₁ and Y ₂ are each independently oxygen, sulfur or selenium,
Ar ₁ to Ar ₆ are each independently a substituted or unsubstituted aryl group having 6 to 50 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms, and the substitution is a halogen atom, cyano group, nitro group, It consists of an aryl group having 6 to 50 carbon atoms, a heteroaryl group having 5 to 50 carbon atoms, an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group having 3 to 50 carbon atoms, a thio group having 1 to 50 carbon atoms, and a silyl group having 1 to 50 carbon atoms. ,
Ar is selected from the following structural formulas 1 to 4;
<Structure 1>

<Formula 2>

<Structure 3>

<Structure 4>

In structures 1 to 4,
Each X is independently a carbon, silicon, germanium, phosphorus or sulfur atom,
R ₁ to R ₂₀ are each independently hydrogen, halogen atom, cyano, nitro, substituted or unsubstituted aryl group having 6 to 50 carbon atoms, substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms, substituted or unsubstituted Substituted alkyl group having 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 50 carbon atoms, substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, substituted or unsubstituted alkynyl group having 1 to 50 carbon atoms, substituted or unsubstituted A substituted C1-C50 silyl group, a substituted or unsubstituted C1-C50 amino group, or a substituted or unsubstituted C1-C50 boraneyl group, wherein R ₁ to R ₂₀ are each independently or together with an adjacent group Can form saturated or unsaturated rings,
m1 to m4, m6 to m9, m12 to m14 and m17 to m20 are each independently an integer of 1 to 4, m5 is 1 or 2, m10, m11 and m15 are each independently an integer of 1 to 3, m16 Is 1,
n is an integer of 0 to 4). delete The method according to claim 1,
In the formula 1 or 2 Y ₁ to Y ₃ Is an organic solar cell, characterized in that oxygen. The method according to claim 1,
The organic solar cell, characterized in that the organic layer is formed by applying a coating composition comprising the phosphine derivative compound and a polar solvent on the upper surface of the light absorbing layer and dried. The method of claim 4,
The polar solvent is an alcohol solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, glycerol, propylene glycol and 1,3-butylene glycol, a ketone solvent selected from acetone, butanone and pentanone, Cyclic ether solvent selected from the group consisting of ester solvents selected from the group consisting of ethyl acetate and butyl acetate, dioxane and tetrahydrofuran, acetonitrile, dimethylformamide and dimethyl sulfoxide Organic solar cell, characterized in that the singly or a mixture thereof. The method according to claim 1,
The organic solar cell, characterized in that the organic layer is formed to 1 to 30 nm. delete Applying a transparent electrode material on the substrate to form a first electrode;
Forming a hole transport layer by applying a hole transport material on the first electrode;
Forming a light absorption layer by applying a mixture of a hole acceptor and an electron acceptor mixed with a solvent on the hole transport layer;
An organic layer forming step of applying a coating composition comprising a phosphine derivative compound represented by the following formula (1) or (2) and a polar solvent on the upper surface of the light absorption layer and dried; And
And forming a second electrode by applying a conductive metal material on the organic layer.
<Formula 1>

<Formula 2>

(Formula 1 and 2,
Y ₁ and Y ₂ are each independently oxygen, sulfur or selenium,
Ar ₁ to Ar ₆ are each independently a substituted or unsubstituted aryl group having 6 to 50 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms, and the substitution is a halogen atom, cyano group, nitro group, It consists of an aryl group having 6 to 50 carbon atoms, a heteroaryl group having 5 to 50 carbon atoms, an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group having 3 to 50 carbon atoms, a thio group having 1 to 50 carbon atoms, and a silyl group having 1 to 50 carbon atoms. ,
Ar is selected from the following structural formulas 1 to 4;
<Structure 1>

<Formula 2>

<Structure 3>

<Structure 4>

In structures 1 to 4,
Each X is independently a carbon, silicon, germanium, phosphorus or sulfur atom,
R ₁ to R ₂₀ are each independently hydrogen, halogen atom, cyano, nitro, substituted or unsubstituted aryl group having 6 to 50 carbon atoms, substituted or unsubstituted heteroaryl group having 5 to 50 carbon atoms, substituted or unsubstituted Substituted alkyl group having 1 to 50 carbon atoms, substituted or unsubstituted cycloalkyl group having 3 to 50 carbon atoms, substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, substituted or unsubstituted alkynyl group having 1 to 50 carbon atoms, substituted or unsubstituted A substituted C1-C50 silyl group, a substituted or unsubstituted C1-C50 amino group, or a substituted or unsubstituted C1-C50 boraneyl group, wherein R ₁ to R ₂₀ are each independently or together with an adjacent group Can form saturated or unsaturated rings,
m1 to m4, m6 to m9, m12 to m14 and m17 to m20 are each independently an integer of 1 to 4, m5 is 1 or 2, m10, m11 and m15 are each independently an integer of 1 to 3, m16 Is 1,
n is an integer of 0 to 4). delete The method according to claim 8,
The polar solvent is an alcohol solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, glycerol, propylene glycol and 1,3-butylene glycol, a ketone solvent selected from acetone, butanone, pentanone, An ester solvent selected from the group consisting of ethyl acetate and butyl acetate, a cyclic ether solvent selected from the group consisting of dioxane, tetrahydrofuran, acetonitrile, dimethylformamide and dimethyl sulfoxide Method for producing an organic solar cell, characterized in that the singly or a mixture thereof.

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