KR101637058B1

KR101637058B1 - Nitrogen-containg compound and organic solar cell comprising the same

Info

Publication number: KR101637058B1
Application number: KR1020120090764A
Authority: KR
Inventors: 김진석; 장송림; 배재순; 이재철; 이지영; 조근
Original assignee: 주식회사 엘지화학
Priority date: 2012-08-20
Filing date: 2012-08-20
Publication date: 2016-07-07
Also published as: KR20140025622A

Abstract

The present invention provides a nitrogen-containing compound capable of significantly improving the lifetime, efficiency, electrochemical stability, and thermal stability of an organic solar cell and an organic solar cell containing the nitrogen-containing compound in the photoactive layer.

Description

TECHNICAL FIELD [0001] The present invention relates to a nitrogen-containing compound and an organic solar cell including the same. BACKGROUND ART < RTI ID = 0.0 >

The present specification relates to nitrogen-containing compounds and organic solar cells containing the same.

Solar cells are devices that can convert solar energy directly into electrical energy by applying a photovoltaic effect. Solar cells can be divided into inorganic solar cells and organic solar cells depending on the material constituting the thin film. A typical solar cell is made of p-n junction by doping crystalline silicon (Si), which is an inorganic semiconductor. Electrons and holes generated by absorption of light are diffused to the p-n junction, accelerated by the electric field, and moved to the electrode. The power conversion efficiency of this process is defined as the ratio of the power given to the external circuit to the solar power input to the solar cell, and is achieved up to 24% when measured under the current standardized virtual solar irradiation conditions. However, since conventional inorganic solar cells have already been limited in economical efficiency and supply / demand of materials, organic semiconductor solar cells, which are easy to process, have various functions and are inexpensive, are seen as long-term alternative energy sources.

Organic solar cells use a variety of organic semiconductor materials in small quantities, which can result in cost savings and can be fabricated using an easy method because they can be fabricated using wet processes.

On the other hand, it is important to increase the efficiency of solar cells so that they can output as much electric energy as possible from solar energy. In order to increase the efficiency of such a solar cell, it is also important to generate as many excitons as possible in the semiconductor, but it is also important to draw generated charges out without loss. One of the causes of loss of charge is that the generated electrons and holes are destroyed by recombination. Various methods have been proposed as methods for transferring generated electrons and holes to electrodes without loss, but most of them require additional processing, which may increase the manufacturing cost.

The possibility of organic solar cells was first suggested in the 1970s, but efficiency was too low to be practical. However, in 1986, CW Tang of Eastman Kodak showed the possibility of practical use as various solar cells with a double layer structure using copper phthalocyanine (CuPc) and perylene tetracarboxylic acid derivatives Two-layer organic photovoltaic cell CW Tang, Appl. Phys. Lett., 48, 183 (1986)). In 1995, the concept of BHJ (Bulk heteojunction) was introduced by Yu et al. (Network of Internal Donor-Acceptor Heterojunctions, G. Yu, J. Gao, JC Hummelen, F. Wudl, AJ Heeger, 1789 (1995)), and fullerene derivatives having improved solubility such as PCBM have been developed as n-type semiconductor materials, thereby remarkably improving the efficiency of organic solar cells. Thereafter, development of materials for organic solar cells is continuously required.

Two-layer organic photovoltaic cells (C. W. Tang, Appl. Phys. Lett., 48, 183. (1996) Yu, J. Gao, J. C. Hummelen, F. Wudl, A. J. Heeger, Science, 270, 1789. (1995)).

The present disclosure provides novel nitrogenous compounds.

The present invention also provides an organic solar cell comprising the compound.

The technical problems to be solved in the present invention are not limited to the above-mentioned technical problems, and other technical problems which are not mentioned can be clearly understood by the average technician from the following description.

One embodiment of the present disclosure provides a nitrogenous compound comprising a unit represented by the following formula:

[Chemical Formula 1]

In formula (1)

l, m, n and o represent M ₁ , M ₂ , M ₃ And

, &Lt; / RTI >

l is a real number with 0 < l < 1,

m is a real number satisfying 0 < m < 1,

n is a real number satisfying 0 < n < 1,

o is a real number with 0 <o? 1, l + m + n + o = 1,

p is an integer of 1 to 10,000,

The M ₁ To M < ₃ > are each independently a direct bond; A substituted or unsubstituted monocyclic or polycyclic divalent heterocyclic group; A substituted or unsubstituted monocyclic or polycyclic divalent aromatic ring group; Or a substituted or unsubstituted divalent group in which at least two of a monocyclic or polycyclic heterocyclic ring and a monocyclic or polycyclic aromatic ring are condensed.

The M ₁ To M < ₃ > may each independently be selected from substituents represented by any one of the following formulas (2) to (24)

In formulas (2) to (24)

X ₁ and X ₂ are each independently selected from the group consisting of CR'R ", SiR'R", GeR'R ", NR ', PR', O, S and Se,

Y ₁ and Y ₂ are each independently selected from the group consisting of CR ', SiR', GeR ', N and P,

R ₅ to R ₃₄ , R ' and R " are each independently hydrogen; heavy hydrogen; A halogen group; A nitro group; A nitrile group; Imide; -N = CHZ _1; Amide group; A hydroxyl group; Ester group; A carbonyl group; A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms; A substituted or unsubstituted C2 to C25 alkenyl group; A substituted or unsubstituted C1 to C25 alkoxy group; A substituted or unsubstituted thiophene group; A substituted or unsubstituted selenophen group; A substituted or unsubstituted pyrrol group; A substituted or unsubstituted thiazole group; A substituted or unsubstituted arylamine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted polycyclic aryl group, and Z ₁ is hydrogen, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and in formulas (3) to (11), The carbon in which the substituent is not represented in the ring constituting the ring may be substituted with hydrogen or other substituent, and the substituent is the same as defined in R ₅ to R ₃₄ .

Also, one embodiment of the present invention provides an organic solar cell comprising a nitrogen-containing compound of Formula 1, including a first electrode, a second electrode, and one or more photoactive layers.

One or more of the photoactive layer, the electron transporting layer, and the hole transporting layer may comprise a compound selected from the group consisting of The present invention provides an organic solar cell comprising

One embodiment of the present disclosure provides a method of manufacturing a semiconductor device, comprising: preparing a substrate; Forming a first electrode on the substrate; Forming a photoactive layer including the nitrogen-containing compound of Formula 1 on the first electrode; And forming a second electrode on the photoactive layer.

One embodiment of the present disclosure provides a method of manufacturing a semiconductor device, comprising: preparing a substrate; Forming a first electrode on one region of the back surface of the substrate; Forming a hole transport layer on the first electrode; Forming a photoactive layer on the hole transport layer; Forming an electron transport layer on the photoactive layer; And forming a second electrode on the electron transporting layer; Wherein at least one of the hole transporting layer, the photoactive layer, and the electron transporting layer includes the nitrogen-containing compound of Formula 1.

The nitrogen-containing compound represented by the formula (1) can be used as a material for an organic solar cell.

The nitrogenous nitrogen compound according to one embodiment described herein is excellent in thermal stability.

Organic solar cells containing nitrogen-containing compounds according to one embodiment described herein exhibit excellent properties in terms of increase in efficiency and increase in stability.

The aromatic compounds according to one embodiment disclosed herein exhibit deep HOMO levels, various band gaps, various LUMO level states, and electronic stability depending on substituents.

The nitrogen-containing compound represented by Chemical Formula 1 in the present specification can be used purely in organic solar cells including organic solar cells, or mixed with impurities.

The nitrogenous compound according to one embodiment described herein can be applied by a solution coating method.

The organic solar cell including the nitrogen-containing compound according to one embodiment described herein can improve the light efficiency.

The lifetime characteristics of the organic solar battery can be improved by the thermal stability of the nitrogen-containing compound according to one embodiment described herein.

1 shows NMR (nuclear magnetic resonance) spectrum of the compound according to Production Example 1-A.
2 shows the NMR spectrum of the compound according to Preparation Example 1-B.
3 shows a toluene solution of the compound of Production Example 2 and a UV absorption spectrum on a film.
4 shows the toluene solution of the compound according to Production Example 3 and the UV absorption spectrum on a film.
5 shows the cyclic voltammetry of the compound according to Preparation Example 2. FIG.
6 shows the results of cyclic voltammetry of the compound according to Preparation Example 3. FIG.
FIG. 7 shows the current density according to the voltage of the organic solar cell according to Test Example 1. FIG.

Hereinafter, the present invention will be described in detail.

In this specification

Quot; means a moiety bonded to a polymer backbone or other substituent.

In this specification, an electron donor is also referred to as an electron donor and generally has a pair of negative or non-covalent electrons, which means donating electrons to a portion lacking a positive charge or an electron pair. Further, the electron donor in the present specification may excite electrons to an electron receiver having a high electronegativity owing to the abundant electron retention property of the molecule itself when light is received in a state of being mixed with the electron acceptor even if it has no negative or non- And the like.

In this specification, an electron acceptor means receiving electrons from an electron donor.

One embodiment herein provides a compound of formula 1 as described above.

The M < 1 _> To M < ₃ > may each independently be a direct bond.

The M < 1 _> To M < ₃ > may each independently be a substituted or unsubstituted monovalent divalent aromatic ring group.

The M < 1 _> To M < ₃ > are each independently a substituted or unsubstituted polycyclic divalent aromatic ring group.

The M < 1 _> To M < ₃ > may each independently be a substituted or unsubstituted monovalent divalent heterocyclic group.

The M < 1 _> To M < ₃ > may each independently be a substituted or unsubstituted polycyclic divalent heterocyclic group.

The M < 1 _> To M < ₃ > may each independently be a substituted or unsubstituted monocyclic or polycyclic aromatic ring and a substituted or unsubstituted monocyclic or polycyclic heterocyclic ring.

In the general formulas (1) to (24), the halogen group may be fluorine, chlorine, bromine or iodine.

Z ₁ of -N = CHZ ₁ of Formula 1 may be a hydrogen group, an alkyl group, an aryl group. Specifically, it may be a compound having the following structure, but is not limited thereto.

In the above Formulas 1 to 24,

Lt; RTI ID = 0.0 > denoted < / RTI > Z ₂ to Z ₄ may be hydrogen, an alkyl group or an aryl group. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

The term " derived "in this specification, including the above-mentioned" derived ", means that a linking group of the mentioned compound is formed. For example, it is meant that at least one part of the mentioned compound is in a form that it can have a linking group.

In the above general formulas (1) to (24), the amide group

&Lt; / RTI > as shown below. Z ₅ to Z ₇ may be hydrogen, an alkyl group or an aryl group. Specifically, it may be a compound of the following structural formula. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the above general formulas (1) to (24), the ester group

As shown in FIG. Z ₈ to Z ₉ may be hydrogen, an alkyl group or an aryl group. Specifically, it may be a compound of the following structural formula. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the above general formulas (1) to (24), the carbonyl group

Lt; RTI ID = 0.0 > carbonyl < / RTI > Z ₁₀ and Z ₁₁ may be hydrogen, an alkyl group or an aryl group. Specifically, it may be a compound of the following structural formula. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

The alkyl group in the present specification including the above formulas (1) to (24) may be linear, branched or cyclic. The number of carbon atoms of the alkyl group is not particularly limited, but is preferably 1 to 25 carbon atoms. Specific examples thereof include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, A cyclopropyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and the like, but is not limited thereto.

The alkoxy group in the present specification including the above-mentioned formulas 1 to 24 may be a straight chain, a branched chain or a ring chain. The number of carbon atoms of the alkoxy group is not particularly limited, but is preferably 1 to 25 carbon atoms. Specific examples include, but are not limited to, a methoxy group, an ethoxy group, a n-propyloxy group, an iso-propyloxy group, a n-butyloxy group, and a cyclopentyloxy group.

The aryl group in the present specification including the above formulas 1 to 24 may be a monocyclic aryl group or a polycyclic aryl group, and includes a case where an alkyl group having 1 to 25 carbon atoms or an alkoxy group having 1 to 25 carbon atoms is substituted.

When the aryl group is a monocyclic aryl group, the number of carbon atoms is not particularly limited, but is preferably 6 to 25 carbon atoms. Specific examples of the monocyclic aryl group include, but are not limited to, a phenyl group, a biphenyl group, a terphenyl group, and a stilbenyl group.

When the aryl group is a polycyclic aryl group, the number of carbon atoms is not particularly limited. And preferably has 10 to 24 carbon atoms. Specific examples of the polycyclic aryl group include, but are not limited to, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, a perylenyl group, a klycenyl group and a fluorenyl group.

The term "substituted or unsubstituted" in the present specification including the above Chemical Formulas 1 to 24 means a group selected from a halogen group, a nitrile group, a nitro group, a hydroxyl group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkoxy group, an aryloxy group, An alkyl group, an aryl group, an aryl group, a fluorenyl group, a carbazole group, an arylalkyl group, an arylalkenyl group, an aryl group, an aryl group, , A heterocyclic group, and an acetylene group, or does not have any substituent (s).

In Formula 1 according to an embodiment of the present invention, M ₁ may be a compound selected from the substituents represented by Formulas 6, 14, and 15.

In Formula (1) according to an embodiment of the present invention, M ₂ and M ₃ may be a substituent represented by Formula (2).

In Formula (1) according to an embodiment of the present invention, M ₁ is selected from the substituents represented by Formulas (6), (14) and (15), and M ₂ and M ₃ are substituents represented by Formula (2).

In Formula 1 according to an embodiment of the present invention, M ₁ is a substituent represented by any one of Chemical Formulas 25 to 28, and M ₂ and M ₃ are substituents represented by Chemical Formula 29. Nitrogen compound.

In Formula 1 according to an embodiment of the present invention, p is an integer of 1 to 10,000, and may be an integer of 30 to 100. When the value of p is 10,000 or less, the solubility is improved and the solution application method can be carried out easily. When the value of p is 1 to 10,000, the larger the value, the better the electrical characteristics and the mechanical characteristics. Specifically, when the value of p is in the range of 30 to 100, the solubility is further improved, which is more advantageous in application of the solution coating method.

In the formula (1) according to an embodiment of the present invention, the number average molecular weight may be 500 to 1,000,000, more preferably 10,000 to 100,000.

In the formula (1) according to an embodiment of the present invention, the compound may have a molecular weight distribution of 1 to 100, more preferably a molecular weight distribution of 1 to 3.

Specifically, when the number average molecular weight is 10,000 to 100,000, the electrical characteristics and the mechanical properties are further improved, and the solubility is improved, which is more advantageous in application of the solution coating method.

When the molecular weight distribution is in the range of 1 to 3, the electrical and mechanical properties are improved, and the solubility is improved, which is more advantageous in application of the solution coating method.

When the molecular weight distribution is in the range of 1 to 100, the intermolecular bonding force is enhanced. When the molecular weight distribution is less than 100, the effect is better. Specifically, when the molecular weight distribution is 1 to 3, the effect is more effective in terms of intermolecular bonding force.

The molecular weight distribution in this specification is a value obtained by dividing the weight average molecular weight (Mw) by the number average molecular weight (Mn).

In the formula (1) according to one embodiment of the present invention, the terminal group may be a heteroaromatic group. Specifically, the terminal group may be thiophene, furan, or the like. The terminal group may be an aromatic group. Specifically, the terminal group may be benzene, naphthalene, anthracene, or the like. Further, the terminal group may be an alkyl group substituted with a halogen or the like. However, the present invention is not limited to these specific examples.

The nitrogenous nitrogen compound of formula (1) according to one embodiment herein is

&Lt; / RTI >

The nitrogenous nitrogen compound of formula (1) may be a compound represented by any one of the following formulas (A) to (D), but is not limited thereto.

(A)

[Chemical Formula B]

&Lt; RTI ID = 0.0 &

[Chemical Formula D]

The nitrogen-containing compound of formula (1) according to the present invention can be prepared by a multistage chemical reaction. After the monomers are prepared through the alkylation reaction, the Grignard reaction, the Suzuki coupling reaction, and the Stille coupling reaction, the final compound (s) is obtained through a carbon-carbon coupling reaction such as a steel coupling reaction . &Lt; / RTI > When the substituent to be introduced is a boronic acid or a boronic ester compound, it can be prepared through a Suzuki coupling reaction. When the substituent to be introduced is a tributyltin compound, But it is not limited thereto.

Also, one embodiment of the present invention provides an organic solar cell comprising the nitrogen-containing compound represented by Formula 1 as a photoactive layer. Can be used in the photoactive layer by mixing the compound represented by Formula 1 and other impurities.

The present invention also provides an organic solar cell comprising a nitrogen-containing compound represented by Chemical Formula 1 according to an embodiment of the present invention in a hole transporting layer and / or an electron transporting layer. The compound represented by Formula 1 may be mixed with other impurities to be used in the hole transport layer and / or the electron transport layer.

An organic solar cell according to an embodiment of the present invention includes a first electrode, a second electrode, and a photoactive layer. The organic solar cell may further include a substrate, a hole transporting layer, and / or an electron transporting layer. Further, the organic solar cell may further include a hole transporting layer and / or an electron transporting layer, an electron donating material, and / or an electron accepting material.

The substrate may be a glass substrate or a transparent plastic substrate having excellent transparency, surface smoothness, ease of handling, and waterproofness, but is not limited thereto and is not limited as long as it is a substrate commonly used in organic solar cells.

The first electrode may be an anode, and the second electrode may be a cathode. The first electrode may be a cathode, and the second electrode may be an anode.

The anode electrode may be a transparent material having excellent conductivity, but is not limited thereto. Specifically, it may be indium tin oxide (ITO), tin oxide (SnO ₂ ), and zinc oxide (ZnO), but is not limited thereto.

The cathode electrode may be a metal having a small work function, but is not limited thereto. Specifically, it may be a metal such as lithium, magnesium, or an alloy thereof, or a multi-layered material such as Al: Li, Al: BaF ₂ , or Al: BaF ₂ : Ba.

In the organic solar cell, a p-type semiconductor forms an exciton paired with electrons and holes by photoexcitation, and the exciton can be separated into an electron and a hole at a p-n junction. The separated electrons and holes migrate to the n-type semiconductor thin film and the p-type semiconductor thin film, respectively, and they are collected in the first electrode and the second electrode, respectively, so that they can be used as electric energy from the outside.

The organic solar cell may be a bi-layer p-n junction organic solar cell and a bulk heterojunction (BHJ) junction depending on the structure of the photoactive layer. A bi-layer p-n junction type organic solar cell includes a photoactive layer consisting of two layers of a p-type semiconductor thin film and an n-type semiconductor thin film. A BHJ (bulk heterojunction) junction type organic solar cell includes a photoactive layer in which an n-type semiconductor and a p-type semiconductor are blended.

The organic solar cell is characterized in that efficiency is improved remarkably due to a new device configuration and a change in process conditions. Therefore, an electron donor material having a low band gap and an electron acceptor material having a good charge mobility may be included to replace conventional materials.

The hole transporting layer and / or the electron transporting layer material may be a material for efficiently transferring electrons and holes to the photoactive layer, thereby increasing the probability that the generated charge moves to the electrode. However, the hole transporting layer and / or the electron transporting layer material are not particularly limited. The hole transport layer material may be selected from the group consisting of poly (3,4-ethylenediocythiophene) doped with poly (styrenesulfonic acid), N, N'-bis (3-methylphenyl) -N, N'- '-Biphenyl] -4,4'-diamine (TPD). The electron transport layer material may be selected from the group consisting of aluminum trihydroxyquinolate (Alq ₃ ), 1,3,4-oxadiazole derivative PBD (2- (4-bipheyl) -5-phenyl- (3, 4-tris [(3-phenyl-6-trifluoromethyl) quinoxaline-2-yl] benzene), a triazole derivative and the like can be used as the quinoxaline derivative. The hole transporting layer material and / or the electron transporting layer material may be a mixture of a compound represented by the formula (1) or a compound represented by the formula (1) and an impurity.

The photoactive layer may comprise an electron donor material and an electron acceptor material. The electron donor may be a compound of formula (I) of the present invention. The electron donor may be a mixture of the compound of Formula 1 and an impurity.

The electron acceptor material may be a fullerene, a fullerene derivative, a heterocyclic compound, a semiconducting element, a semiconducting compound, or a combination thereof. Specifically, PC ₆₁ BM (phenyl C ₆₁ -butyric acid methyl ester) or PC ₇₁ BM (phenyl C ₇₁ -butyric acid methyl ester), but the present invention is not limited to these examples.

The photoactive layer can form a BHJ (Bulk Heterojunction) by an electron donor and an electron acceptor. The electron donor material and the electron acceptor material may be mixed at a ratio (w / w: mass ratio) of 1:10 to 10: 1. After the electron donor and electron donor materials are mixed, annealing may be performed at 30 to 300 ° C for 1 second to 24 hours to maximize the properties.

The thickness of the photoactive layer may be 10 to 10,000 ANGSTROM, but is not limited thereto.

The organic solar battery may be arranged in the order of an anode, a photoactive layer, and a cathode, and may be arranged in the order of a cathode, a photoactive layer, and an anode, but is not limited thereto.

The organic solar battery may be arranged in the order of an anode, a hole transporting layer, a photoactive layer, an electron transporting layer and a cathode, and may be arranged in the order of a cathode, an electron transporting layer, a photoactive layer, a hole transporting layer and an anode.

Conventional electron donor materials have been studied mainly on p-type conductive polymers, but they have not yet absorbed much of the solar spectrum because the band gap is large. In addition, since the solubility of the polymer is poor, there is a limit in using a spin coating process, a roll-to-roll process, or an inkjet printing process through a solution process. In addition, a BHJ device through combination with an electron acceptor material such as a fullerene derivative has a maximum efficiency of 8%, and thus a novel photoactive material having improved electronic characteristics has been required for commercialization.

However, the organic solar cell according to one embodiment of the present invention exhibits excellent characteristics in terms of an increase in efficiency and an increase in stability. The compound represented by formula (1) of the present invention is excellent in thermal stability. The compound represented by the general formula (1) of the present invention has HOMO level, various bandgaps, various LUMO level states, and electronic stability, thereby exhibiting excellent properties.

The compound represented by the formula (1) according to an embodiment of the present invention has excellent solubility and is applicable as a solution coating method in an organic solar cell.

In addition, the organic solar cell using the compound represented by Chemical Formula 1 according to one embodiment of the present invention has improved light efficiency. Further, the lifetime characteristics of the organic solar battery can be improved by the thermal stability of the compound.

The role of the photoactive material that absorbs light to generate energy in the organic solar cell is mainly performed by the electron donor material. Thus, it is desirable that the electron donor material is capable of absorbing light in a broad spectral range to absorb as much sunlight as possible.

The compound of Chemical Formula 1 according to an embodiment of the present invention absorbs a wavelength of 300 to 700 nm and can absorb a wide range of sunlight corresponding to ultraviolet rays, visible rays, and near-infrared rays of sunlight, It can be said that it is preferable as a material.

The organic solar cell of the present invention can be produced by materials and methods known in the art except that the photoactive layer contains the compound of the present invention, i.e., the nitrogen-containing compound represented by the above formula (1).

The organic solar cell of the present invention can be produced by materials and methods known in the art except that the hole transporting layer and / or electron transporting layer contains the compound of the present invention, i.e., the nitrogen-containing compound represented by the above formula have.

A method of manufacturing an organic solar cell according to an embodiment of the present invention includes preparing a substrate, forming an anode on a back surface of the substrate, forming a photoactive layer on the anode, and forming a cathode on the photoactive layer .

A method of manufacturing an organic solar cell according to an embodiment of the present invention includes preparing a substrate, forming a cathode on a back surface of the substrate, forming a photoactive layer on the cathode, and forming an anode on the photoactive layer .

Further, a method of manufacturing an organic solar cell according to an embodiment of the present invention includes the steps of preparing a substrate, forming an anode on a back surface of the substrate, forming a hole transporting layer on the anode, Forming a photoactive layer, forming an electron transport layer on the photoactive layer, and forming a cathode on the electron transport layer.

Further, a method of manufacturing an organic solar cell according to an embodiment of the present invention includes the steps of preparing a substrate, forming a cathode on the back surface of the substrate, forming an electron transport layer on the cathode, Forming a photoactive layer, forming a hole transport layer on the photoactive layer, and forming an anode on the hole transport layer.

In the above-described method for producing an organic solar cell, a solution coating method may be used in forming the photoactive layer.

The organic solar cell of the present specification can be produced, for example, by sequentially laminating an anode, a photoactive layer and a cathode on a substrate.

The organic solar cell of the present specification can be produced by sequentially laminating an anode, a hole transporting layer, a photoactive layer, an electron transporting layer and a cathode on a substrate. At this time, they may be coated by a wet method such as gravure printing, offset printing, screen printing, ink jet, spin coating, spray coating and the like, but not limited thereto.

The production method of the nitrogen-containing compound of the above formula (1) and the production of the organic solar cell using the same are specifically described in the following Production Examples and Examples. However, the following Preparation Examples and Examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

< Manufacturing example 1-A> Monomeric Synthesis of (2- (2- ( Thiophene -2 days) Ethynyl ) Thiophene (2- (2- (thiophen-2-yl) ethynyl) thiophene)

[ Manufacturing example 1-a]

(2-bromothiophene, 5.00 g, 23.8 mmol), CuI (Copper iodide, 0.450 g, 2.38 mmol) and PdCl ₂ (PPh ₃ ) ₂ (Bis (triphenylphosphine) palladium (II) chloride, 1.00 g, 1.43 mmol), and then DBU (1,8-Diazabicycloundec-7-ene, 21.7 g, 143 mmol) was added thereto. After stirring at room temperature for 30 minutes, add ethynyl (trimethyl) silane (1.17 g, 11.9 mmol) and immediately add 0.171 ml of water. Stir for 18 hours, extract with ethyl ether, wash 3 times with distilled water, 3 times with 10 wt% HCl (Hydrochloric acid) aqueous solution, and 3 times with saline solution. The remaining amount of water is removed with MgSO ₄ (magnesium sulfate), the solvent is removed under vacuum, and the residue is purified by column chromatography (eluent: hexane) to obtain a white solid.

Yield: 85.2%

1 shows the NMR spectrum of the compound according to Preparation Example 1-A.

< Manufacturing example 1-B> Monomeric Synthesis (2,3- die -2- Cyienbuta -1,3- Daien -1,1,4,4, -tetracarbonitrile (2,3- Di -2- thienylbuta -1,3- diene -1,1,4,4- 테트라 카carbonitrile ))

[ Manufacturing example 1-B]

(2- (2- (thiophen-2-yl) ethynyl) thiophene (1.78 g, 9.35 mmol) and TCNE (tetracyanoethylene, 3.59, 28.1 mmol ) Were mixed, followed by stirring at 150 ° C for 14 hours. The resulting mixture is purified by column chromatography (eluent: methylenechloride) to obtain an orange solid.

Yield: 52.1%

2 shows the NMR spectrum of the compound according to Preparation Example 1-B.

< Manufacturing example 1-C > Monomeric Synthesis (2,3- Bis (5-bromothiophen-2-yl) buta -1,3- Daien -1,1,4,4-tetracarbonitrile (2,3- bis (5- bromothiophen -2- yl ) buta-1,3- diene -1,1,4,4-tetracarbonitrile)

To 10 ml of chloroform was added 2,3-di-2-thienylbuta-1,3-diene-1,1,4,4-tetranabutyrate (2,3-Di- N-bromosuccinimide (0.657 g, 1.52 mmol) was added to the solution, and the mixture was stirred for 12 hours Lt; / RTI > After cooling to room temperature, distilled water was added, and the mixture was extracted with chloroform. The remaining amount of water was removed with MgSO ₄ , and the solvent was removed in vacuo. The residue was redissolved in chloroform and methanol (MeOH) A crystalline solid was obtained.

Yield: 67%

MS: [M + H] < ⁺ > = 476

< Manufacturing example 2> polymerization of the compound (poly (N-9- Heptadecanyl carbazole - Alt -2,3- die -2- Cyienbuta -1,3- Daien -1, 1, 4, 4, - Tetracarbonitrile ) (poly (N-9- heptadecanylcarbazole - bottom -2,3- Di -2- thienylbuta -1,3- diene -1,1,4,4-tetracarbonitrile)

[ Manufacturing example 2]

As used herein, the term 2,7-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -N, 9-heptadecanylcarbazole Bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -N, 9-heptadecanylcarbazole) was prepared by referring to the previous literatures. (N.Blouin, A. Michaud, M. Leclerc, Adv. Mater. 19, 2007, 2295-2300)

(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -N, 9-heptadecanylcarbazole (787 mg, 1.20 mmol), 2,3-bis (5-bromothiophen-2-yl) buta-1,3-diene-1,1,4,4-tetracarbonitrile bromothiophen-2-yl) buta- 1,3-diene-1,1,4,4-tetracarbonitrile 571 mg, 1.20 mmol), 20 wt% Et4NOH (tetraethylhydroxide) aqueous solution _{30 ml, Pd (PPh 3)} 4 (tetrakis ( After 72 hours, the mixture was cooled to room temperature, methanol was poured off, and the mixture was extracted with acetone, hexane, chloroform, and then precipitated in methanol. The residue was dissolved in acetone, hexane and chloroform, I filtered out the solid.

Yield: 56%

Number average molecular weight: 4,500 g / mol

Weight average molecular weight: 6,100 g / mol

3 shows a toluene solution of the compound of Production Example 2 and a UV absorption spectrum on a film.

The UV absorption spectrum of the film in FIG. 3 was obtained by dissolving the compound in chlorobenzene at a concentration of 1 wt%, dropping the solution onto a glass substrate, and spin-coating the sample at 1000 rpm for 60 seconds using a UV-Vis spectrometer Respectively.

Since the compound synthesized in Preparation Example 2 absorbs a wavelength of 300 to 700 nm, it can absorb a wide range of sunlight corresponding to ultraviolet rays, visible rays, and near-infrared rays of sunlight, .

5 shows the cyclic voltammetry of the compound according to Preparation Example 2. FIG.

5, cyclic voltametry was performed using a glassy carbon working electrode and an Ag / Agcl reference electrode, an Ag / AgCl reference electrode, and an Ag / AgCl reference electrode in an electrolyte solution in which Bu ₄ NBF ₄ was dissolved in acetonitrile at 0.1 M, The Pt electrode was deposited and analyzed by the three electrode method. The compound was coated on a working electrode by a drop casting method.

The compound synthesized in Preparation Example 2 shows an oxidation potential of 1.1 to 1.2 V (ws Ag / AgCl). The oxidation level measured by the cyclic voltammetry can be converted to the HOMO energy level by a constant equation (HOMO (eV) = - (4.4 + oxidation potential (V)) (ws Ag / Agcl) The HOMO energy level corresponding to the above potential value is -5.5 to 5.6 eV. In the organic solar cell, one of the important factors for determining the open-circuit voltage is the difference between the HOMO energy level of the electron-injecting compound and the LUMO energy level of the electron-accepting compound. That is, as the HOMO energy level of the electron-spinning compound is located deeper, the open-circuit voltage of the device becomes larger, and the compound itself can have oxidation stability. Therefore, the oxidation potential of the preferred compound is 0.8 V (ws Ag / AgCl) or more. However, when the oxidation potential of the compound is too high and the HOMO energy level is located too deep, the holes generated during the operation of the device may not be extracted into the anode, so that it is more preferable that the oxidation potential has a value between 0.7 and 1.2 V . Therefore, the compound synthesized in Preparation Example 2 has a preferable oxidation potential value.

< Manufacturing example 3> Synthesis of compound (poly (9,9- Dioctylfluorene - Alt -2,3- die -2- Cyienbuta -1,3- Daien -1, 1, 4, 4, - Tetracarbonitrile ) (poly (9,9- 옥시 트리 플렌렌 - bottom -2,3-Di-2-thienylbuta-1,3-diene-1,1,4,4-tetracarbonitrile)

[ Manufacturing example 3]

To 50 ml of toluene was added 2,7-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9,9-dioctylfluorene mg, 1.55 mmol), 2,3-bis (5-bromothiophen-2-yl) buta-1,3-diene-1,1,4,4-tetracarbonitrile 5-bromothiophen-2-yl) buta-1,3-diene-1,1,4,4-tetracarbonitrile 738 mg, 1.55 mmol), 20wt% Et4NOH (tetraethylhydroxide) aqueous solution _{10 ml, Pd (PPh 3)} 4 (tetrakis After 72 hours, the mixture was cooled to room temperature, poured into methanol, and the solid was filtered off. Soxhlet extraction was performed on acetone, hexane and chloroform, It was precipitated again in methanol to remove the solid.

Yield: 63%

Number average molecular weight: 29,100 g / mol

Weight average molecular weight: 42,200 g / mol

4 shows the toluene solution of the nitrogen-containing compound according to Preparation Example 3 and the UV absorption spectrum of the film.

The UV absorption spectrum of the film in FIG. 4 was obtained by dissolving the compound in chlorobenzene at a concentration of 1 wt%, dropping the solution onto a glass substrate, and spin-coating the sample at 1000 rpm for 60 seconds using a UV-Vis spectrometer Respectively.

Since the compound synthesized in Preparation Example 3 absorbs a wavelength of 300 to 700 nm, it can absorb a wide range of sunlight corresponding to ultraviolet rays, visible rays, and near-infrared rays of sunlight, .

6 shows the results of cyclic voltammetry of the compound according to Preparation Example 3. FIG.

The cyclic voltammetry of FIG. 6 was carried out by adding a glassy carbon working electrode and an Ag / Agcl reference electrode to an electrolyte solution obtained by dissolving Bu ₄ NBF ₄ in acetonitrile at 0.1 M, The Pt electrode was deposited and analyzed by the three electrode method. The compound was coated on a working electrode by a drop casting method.

The compound synthesized in Preparation Example 3 shows an oxidation potential of 1.1 to 1.2 V (ws Ag / AgCl). The oxidation level measured by the cyclic voltammetry can be converted to the HOMO energy level by a constant equation (HOMO (eV) = - (4.4 + oxidation potential (V)) (ws Ag / Agcl) The HOMO energy level corresponding to the above potential value is -5.5 to 5.6 eV. In the organic solar cell, one of the important factors for determining the open-circuit voltage is the difference between the HOMO energy level of the electron-injecting compound and the LUMO energy level of the electron-accepting compound. That is, as the HOMO energy level of the electron-spinning compound is located deeper, the open-circuit voltage of the device becomes larger, and the compound itself can have oxidation stability. Therefore, the oxidation potential of the preferred compound is 0.8 V (ws Ag / AgCl) or more. However, when the oxidation potential of the compound is too high and the HOMO energy level is located too deep, the holes generated during the operation of the device may not be extracted into the anode, so that it is more preferable that the oxidation potential has a value between 0.7 and 1.2 V . Therefore, the compound synthesized in Production Example 3 has a preferable oxidation potential value.

< Example 1> Manufacture of organic solar cell

The compound prepared in Preparation Example 2 and PCBM were dissolved in 1,2-dichlorobenzene (DCB) at a ratio of 1: 4 to prepare a composite solution. At this time, the concentration was adjusted to 1.0 to 2.0 wt%, and the organic solar cell was made of ITO / PEDOT: PSS / photoactive layer / LiF / Al. The ITO-coated glass substrate was ultrasonically cleaned using distilled water, acetone, and 2-propanol, and the ITO surface was ozone-treated for 10 minutes and spin coated with PEDOT: PSS (baytrom P) Min. For the coating of the photoactive layer, the compound-PCBM composite solution was filtered with a 0.45 μm PP syringe filter, then spin-coated, and heat-treated at 120 ° C. for 5 minutes. Using a thermal evaporator under a vacuum of 3 × 10 ^-8 torr LiF was deposited to a thickness of 7 Å, and Al was deposited to a thickness of 200 nm to prepare an organic solar cell.

< Example 2> Manufacture of organic solar cell

The compound prepared in Preparation Example 3 and PCBM were dissolved in 1,2-dichlorobenzene (DCB) at a ratio of 1: 4 to prepare a composite solution. At this time, the concentration was adjusted to 1.0 to 2.0 wt%, and the organic solar cell was made of ITO / PEDOT: PSS / photoactive layer / LiF / Al. The ITO-coated glass substrate was ultrasonically cleaned using distilled water, acetone, and 2-propanol, and the ITO surface was ozone-treated for 10 minutes and spin coated with PEDOT: PSS (baytrom P) Min. For the coating of the photoactive layer, the compound-PCBM composite solution was filtered with a 0.45 μm PP syringe filter, then spin-coated, and heat-treated at 120 ° C. for 5 minutes. Using a thermal evaporator under a vacuum of 3 × 10 ^-8 torr LiF was deposited to a thickness of 7 Å, and Al was deposited to a thickness of 200 nm to prepare an organic solar cell.

< Comparative Example 1> Manufacture of organic solar cell

P3HT and PCBM were dissolved in 1,2-dichlorobenzene (DCB) at a ratio of 1: 1 to prepare a composite solution. At this time, the concentration was adjusted to 1.0 to 2.0 wt%, and the organic solar cell was made of ITO / PEDOT: PSS / photoactive layer / LiF / Al. The ITO-coated glass substrate was ultrasonically cleaned using distilled water, acetone, and 2-propanol, and the ITO surface was ozone-treated for 10 minutes and spin coated with PEDOT: PSS (baytrom P) Min. For the coating of the photoactive layer, the compound-PCBM composite solution was filtered with a 0.45 μm PP syringe filter, then spin-coated, and heat-treated at 120 ° C. for 5 minutes. Using a thermal evaporator under a vacuum of 3 × 10 ^-8 torr LiF was deposited to a thickness of 7 Å, and Al was deposited to a thickness of 200 nm to prepare an organic solar cell.

< Test Example 1>

The photoelectric conversion characteristics of the organic solar cells prepared in Examples 1 to 2 and Comparative Example 1 were measured under the conditions of 100 mW / cm ² (AM 1.5), and the results are shown in Table 1 below.

Active layer Total thickness
(nm) V _OC
(V) J _SC
(mA / cm ² ) FF PCE
(%) Example 1 A / PC ₆₁ BM = 1: 4 89 0.57 1.50 30 0.25 Example 2 Formula B / PC ₆₁ BM = 1: 4 93 0.57 1.80 33 0.30 Comparative Example 1 P3HT / PC ₆₁ BM = 1: 1 90 0.72 8.30 45.5 2.81

In Table 1, the total thickness means the thickness of the active layer in the organic solar cell, V _oc is the open voltage, J _sc is the short-circuit current, FF is the fill factor, and PCE is the energy conversion efficiency. The open-circuit voltage and the short-circuit current are the X-axis and Y-axis intercepts in the fourth quadrant of the voltage-current density curve, respectively. The higher the two values, the higher the efficiency of the solar cell. The fill factor is the width of the rectangle that can be drawn inside the curve divided by the product of the short-circuit current and the open-circuit voltage. The energy conversion efficiency can be obtained by dividing these three values by the intensity of the irradiated light, and a higher value is preferable

FIG. 7 shows the current density according to the voltage of the organic solar cell according to Experimental Example 1. FIG.

The method of measuring the current density is as follows. The compound prepared in Preparation Examples 2 and 3 and PCBM were dissolved in 1,2-dichlorobenzene (DCB) to prepare a composite solution. At this time, the concentration was adjusted to 1.0 to 2.0 wt%, and the organic solar cell was made of ITO / PEDOT: PSS / photoactive layer / LiF / Al. The ITO-coated glass substrate was ultrasonically cleaned using distilled water, acetone, and 2-propanol, and the ITO surface was ozone-treated for 10 minutes and spin coated with PEDOT: PSS (baytrom P) Min. In order to coat the photoactive layer, the compound-PCBM composite solution was filtered with a 0.45 μm PP syringe filter, followed by spin coating, heat treatment at 120 ° C. for 5 minutes, and thermal evaporation under a vacuum of 3 × 10 ^-8 torr LiF was deposited to a thickness of 7 Å, and Al was deposited to a thickness of 200 nm. The photoelectric conversion characteristics of the organic solar cell thus prepared were measured under the conditions of 100 mW / cm ² (AM 1.5).

Under the solar irradiation condition, the current density curve according to the voltage of the organic solar cell indicates how efficiently the organic solar cell is producing energy. In the fourth quadrant of the voltage-current density curve, the X-axis and Y-axis intercepts represent the open-circuit voltage and the short-circuit current, respectively, and the higher the two values, the higher the efficiency of the solar cell is. Also, a value obtained by dividing the width of a rectangle which can be drawn inside this curve by the product of the short-circuit current and the open-circuit voltage is called a fill factor, and the higher the value, the better the efficiency.

Claims

A nitrogen-containing compound comprising a unit represented by the following formula (1):
[Chemical Formula 1]

In formula (1)
l, m, n, and o are, respectively, M ₁ , M ₂ , M ₃ ,

, &Lt; / RTI >
l is a real number with 0 < l < 1,
m is a real number satisfying 0 < m < 1,
n is a real number satisfying 0 < n < 1,
o is a real number with 0 <o? 1, l + m + n + o = 1,
p is an integer from 30 to 100,
Wherein M1 is represented by the following formula (6)
M2 and M3 are each represented by the following general formula (2)
(2)

[Chemical Formula 6]

In formulas (2) and (6)
X ₁ is selected from the group consisting of CR'R ", SiR'R", GeR'R ", NR ', PR', O, S and Se,
R ₅ , R ₆ , R ' and R " are each independently hydrogen; heavy hydrogen; A halogen group; A nitro group; A nitrile group; Imide; -N = CHZ _1; Amide group; A hydroxyl group; Ester group; A carbonyl group; An alkyl group having 1 to 25 carbon atoms; An alkenyl group having 2 to 25 carbon atoms; An alkoxy group having 1 to 25 carbon atoms; Thiophene group; Selenophen group; A roll roll; Thiazole group; An arylamine group; An aryl group; Or a polycyclic aryl group, Z ₁ is hydrogen, an alkyl group, or an aryl group,
In the formula (6), the carbon in which the substituent is not represented in the carbon atoms constituting the ring may be substituted with hydrogen or other substituent, and the substituent is the same as defined in R ₅ and R ₆ .

delete

The nitrogen-containing compound according to claim 1, wherein M ₁ is a substituent represented by the following Chemical Formula 25 or 26, and M ₂ and M ₃ are substituents represented by Chemical Formula 29:

The nitrogen-containing compound according to claim 1, wherein the nitrogen-containing compound comprises a structure represented by the following formula (A) or (B)
(A)

[Chemical Formula B]

The nitrogen-containing compound according to any one of claims 1, 6 and 7, wherein the nitrogen-containing compound absorbs a solar wavelength of up to 300 to 700 nm.

delete

A nitrogen-containing compound according to any one of claims 1, 6 and 7, wherein the molecular weight distribution is 1 to 100.

The nitrogen-containing compound according to any one of claims 1, 6 and 7, wherein the number average molecular weight is 500 to 1,000,000.

Wherein the photoactive layer comprises a first electrode, a second electrode, and at least one photoactive layer, wherein at least one of the photoactive layers includes the nitrogen containing compound according to any one of claims 1, 6, and 7.

The organic solar cell according to claim 12, wherein the photoactive layer comprises an electron donor material and an electron acceptor material, and the electron donor material comprises the nitrogen containing compound.

14. The organic solar battery according to claim 13, wherein the electron-accepting material comprises one or more selected from the group consisting of fullerene, fullerene derivatives, vasocopherin, semiconducting elements and semiconducting compounds.

At least one of a photoactive layer, an electron transport layer, and a hole transport layer comprises a first electrode, a second electrode, at least one photoactive layer, an electron transport layer and a hole transport layer, Wherein the organic solar cell comprises a nitrogen compound.

16. The organic solar battery according to claim 15, wherein the photoactive layer comprises an electron donor material and an electron acceptor material, and at least one of the electron donor material, the electron transport layer and the hole transport layer comprises the nitrogen nitrogen compound.

17. The organic solar battery according to claim 16, wherein the electron acceptor material comprises one or more selected from the group consisting of fullerene, fullerene derivative, vasocopherin, semiconducting element and semiconducting compound.

Preparing a substrate;
Forming a first electrode on the substrate;
Forming a photoactive layer comprising the nitrogen-containing compound according to any one of claims 1, 6 and 7 on the first electrode; And
And forming a second electrode on the photoactive layer.

19. The method of manufacturing an organic solar cell according to claim 18, wherein a solution coating method is used to form the photoactive layer.

Preparing a substrate;
Forming a first electrode on one region of the back surface of the substrate;
Forming a hole transport layer on the first electrode;
Forming a photoactive layer on the hole transport layer;
Forming an electron transport layer on the photoactive layer; And
Forming a second electrode on the electron transporting layer;
Wherein at least one of the hole transporting layer, the photoactive layer, and the electron transporting layer includes the nitrogen-containing compound according to any one of claims 1, 6, and 7.

The method of manufacturing an organic solar cell according to claim 20, wherein the layer containing the nitrogen-containing compound is formed using a solution coating method.