KR20190136277A - Heterocyclic compound, organic electronic device comprising the same and method for manufacturing organic electronic device using the same - Google Patents

Abstract

The present specification relates to: a heterocyclic compound represented by chemical formula 1, an organic electronic device comprising the heterocyclic compound in an organic active layer; and a method for manufacturing the organic electronic device using the heterocyclic compound. Since the heterocyclic compound has a wide light absorption region and a high LUMO energy level according to an embodiment of the present specification, when the heterocyclic compound is used in the organic active layer of the organic electronic device, it is possible to obtain a high level of efficiency.

Description

Heterocyclic compound, organic electronic device comprising the same and method for manufacturing organic electronic device using same {HETEROCYCLIC COMPOUND, ORGANIC ELECTRONIC DEVICE COMPRISING THE SAME AND METHOD FOR MANUFACTURING ORGANIC ELECTRONIC DEVICE USING THE SAME}

The present specification relates to a heterocyclic compound, an organic electronic device including the same, and a method of manufacturing the organic electronic device using the same.

In the present specification, an organic electronic device is an electronic device using an organic semiconductor material, and requires an exchange of holes and / or electrons between an electrode and an organic semiconductor material. The organic electronic device can be divided into two types according to the operating principle. First, an exciton is formed in the organic layer by photons introduced into the device from an external light source, and the exciton is separated into electrons and holes, and these electrons and holes are transferred to different electrodes to be used as current sources (voltage sources). It is an electronic device of the form. The second type is an electronic device in which holes and / or electrons are injected into the organic semiconductor material layer that interfaces with the electrodes by applying voltage or current to two or more electrodes, and is operated by the injected electrons and holes.

Examples of organic electronic devices include organic solar cells, organic photoelectric devices, organic light emitting devices, organic photoconductors (OPCs), and organic transistors, all of which are electron / hole injection materials, electron / hole extraction materials, and electrons for driving the devices. Requires a hole transport material or a luminescent material. Hereinafter, the organic solar cell will be described in detail. However, in the organic electronic devices, the electron / hole injection material, the electron / hole extraction material, the electron / hole transport material, or the light emitting material all operate on a similar principle.

Solar cells are batteries that change electrical energy directly from sunlight, and research is being actively conducted because they are a clean alternative energy source for solving the environmental problems caused by the depletion of fossil energy and its use. Here, the solar cell refers to a battery that generates a current-voltage by using a photovoltaic effect that absorbs light energy from sunlight and generates electrons and holes.

Solar cells are devices that can directly convert solar energy into electrical energy by applying the photovoltaic effect. Solar cells can be divided into inorganic solar cells and organic solar cells, depending on the material of the thin film.

Through a variety of layers and electrodes according to the design of the solar cell, a lot of research to improve the energy conversion efficiency is in progress.

Two-layer organic photovoltaic cell (C.W.Tang, Appl. Phys. Lett., 48, 183. (1986)) Efficiencies via Network of Internal Donor-Acceptor Heterojunctions (G. Yu, J. Gao, J. C. Hummelen, F. Wudl, A. J. Heeger, Science, 270, 1789. (1995))

An object of the present invention is to provide a heterocyclic compound and an organic electronic device comprising the same.

An exemplary embodiment of the present specification provides a heterocyclic compound represented by Formula 1 below.

[Formula 1]

In Chemical Formula 1,

R1 to R8 are each hydrogen; Or a substituted or unsubstituted alkyl group,

Ra to Rf are each hydrogen; Substituted or unsubstituted alkyl group; Or a substituted or unsubstituted aryl group,

L1 to L4 each represent a substituted or unsubstituted arylene group; Or a substituted or unsubstituted divalent heterocyclic group,

Y1 and Y2 are each hydrogen; Substituted or unsubstituted alkyl group; Or a halogen group,

m and n are each an integer of 0-4.

In addition, an exemplary embodiment of the present specification

A first electrode;

A second electrode provided to face the first electrode; And

It is provided between the first electrode and the second electrode, and includes one or more organic material layer including an organic active layer,

The organic active layer provides an organic electronic device comprising the heterocyclic compound.

In addition, an exemplary embodiment of the present specification

Forming a first electrode on the substrate;

Forming an electron transport layer on the first electrode;

Forming at least one organic material layer including an organic active layer on the electron transport layer; And

Forming a second electrode on the organic material layer;

The organic active layer provides a method for producing an organic electronic device comprising the heterocyclic compound.

In the exemplary embodiment of the present specification, since the heterocyclic compound has a wide light absorption region and a high LUMO energy level, when the heterocyclic compound is used in the organic active layer of the organic electronic device, a high level of efficiency may be obtained.

1 is a view showing an organic solar cell according to an exemplary embodiment of the present specification.
Figure 2 is a diagram showing the UV-visible absorption spectrum of the film state of Compound 1, PBDB-T, and Comparative Compound 1.

Hereinafter, this specification is demonstrated in detail.

An exemplary embodiment of the present specification provides a heterocyclic compound represented by Chemical Formula 1.

Previous studies on organic electronic devices have focused on finding electron donor materials that exhibit high efficiency when the electron acceptor of the organic active layer is a fullerene compound such as PCBM. However, organic electronic devices comprising a fullerene compound have an absorption region, an open voltage and Due to the limitations in the performance of device life and the like, researches using non-fullerene-based compounds such as ITIC as electron acceptors are increasing.

The inventors of the present invention applied the compound represented by the formula (1) of the structure containing acetylene among the non-fullerene compound to the electron acceptor of the organic electronic device, the acetylene has a characteristic of attracting electrons of the triple bond (electron withdrawing effect) and Rigid properties allow for superior interactions to absorb light in a wider area than conventional electron acceptor materials, resulting in higher short-circuit currents and ultimately organic solar cells. It was found that the efficiency and stability of the organic electronic device, including.

In the present specification, when a part is used to 'include' a certain component, it means that the component may further include other components, without excluding other components unless specifically stated otherwise.

In the present specification, when a member is located 'on' another member, this includes not only when one member is in contact with another member but also when another member exists between the two members.

In the present specification, the energy level means the magnitude of energy. Therefore, even when the energy level is displayed in the negative (-) direction from the vacuum level, the energy level is interpreted to mean the absolute value of the corresponding energy value. For example, the HOMO energy level means the distance from the vacuum level to the highest occupied molecular orbital. In addition, the LUMO energy level means the distance from the vacuum level to the lowest unoccupied molecular orbital.

In the present specification, the term 'substituted' means that the hydrogen atom bonded to the carbon atom of the compound is replaced with another substituent, and the position to be substituted is not limited as long as the position at which the hydrogen atom is substituted, that is, the position at which the substituent is substituted, 2 When more than one substituent, two or more substituents may be the same or different from each other.

As used herein, the term "substituted or unsubstituted" is deuterium; Halogen group; Hydroxyl group; An alkyl group; Cycloalkyl group; An alkoxy group; Aryloxy group; Alkenyl groups; Aryl group; And it means that is substituted with one or more substituents selected from the group consisting of a heterocyclic group or substituted with a substituent to which two or more substituents among the substituents exemplified above, or have no substituent.

In the present specification, the carbon number of the substituent having a branched chain includes the carbon number of the branched chain. For example, in an alkyl group having 3 to 20 carbon atoms having at least one methyl group as a branched chain, 3 to 20 is a numerical value including carbon number of the at least one methyl group.

In the present specification, the alkyl group may be linear or branched chain, carbon number is not particularly limited, but is preferably 1 to 50. Specific examples include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, iso Pentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl , 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylhexyl, 4-methylhexyl and 5-methylhexyl, and the like.

The alkyl group may be substituted with an aryl group or a heteroaryl group to act as an arylalkyl group or heteroarylalkyl group. The aryl group and heteroaryl group may be selected from examples of the aryl group and heteroaryl group described below, respectively.

In the present specification, the aryl group may be monocyclic or polycyclic.

In the present specification, when the aryl group is a monocyclic aryl group, carbon number is not particularly limited, but preferably 6 to 30 carbon atoms. Specific examples of the monocyclic aryl group include a phenyl group, a biphenyl group, and a terphenyl group, but are not limited thereto.

In the present specification, when the aryl group is a polycyclic aryl group, carbon number is not particularly limited. It is preferable that it is C10-30. Specific examples of the polycyclic aryl group include naphthyl group, anthracenyl group, phenanthryl group, pyrenyl group, peryleneyl group, chrysenyl group, and fluorenyl group, but are not limited thereto. The fluorenyl group may be substituted, and adjacent substituents may be bonded to each other to form a ring.

In the present specification, the heterocyclic group includes one or more atoms other than carbon and heteroatoms, and specifically, the heteroatoms may include one or more atoms selected from the group consisting of O, N, Se, and S, and the like. Although carbon number of a heterocyclic group is not specifically limited, It is preferable that it is C2-C60. Examples of heterocyclic groups include thiophene group, furan group, pyrrole group, imidazole group, thiazole group, oxazole group, oxadiazole group, triazole group, pyridyl group, bipyridyl group, pyrimidyl group, triazine group, triazole group, Acridyl group, pyridazine group, pyrazinyl group, quinolinyl group, quinazoline group, quinoxalinyl group, isoquinoline group, indole group, carbazole group, benzoxazole group, benzimidazole group, benzothiazole group, benzocarbazole group , Benzothiophene group, dibenzothiophene group, benzofuranyl group, phenanthroline group, thiazolyl group, isoxazolyl group, oxadiazolyl group, thiadiazolyl group, phenothiazinyl group and dibenzo Furanyl groups and the like, but are not limited thereto.

The heterocyclic group may be monocyclic or polycyclic, and may be aromatic, aliphatic or a condensed ring of aromatic and aliphatic.

In the present specification, the description of the aforementioned heterocyclic group may be applied except that the heteroaryl group is aromatic.

In the present specification, the arylene group refers to a divalent group having two bonding positions in the aryl group. The description of the aforementioned aryl group can be applied except that they are each divalent.

In the present specification, the heteroarylene group means a divalent group having two bonding positions in the heteroaryl group. The description of the aforementioned heteroaryl group can be applied except that they are each divalent.

An exemplary embodiment of the present specification provides a heterocyclic compound represented by Formula 1 below.

[Formula 1]

In Chemical Formula 1,

R1 to R8 are each hydrogen; Or a substituted or unsubstituted alkyl group,

Ra to Rf are each hydrogen; Substituted or unsubstituted alkyl group; Or a substituted or unsubstituted aryl group,

L1 to L4 each represent a substituted or unsubstituted arylene group; Or a substituted or unsubstituted divalent heterocyclic group,

Y1 and Y2 are each hydrogen; Substituted or unsubstituted alkyl group; Or a halogen group,

m and n are each an integer of 0-4.

In one embodiment of the present specification, L1 to L4 are each a phenylene group.

In one embodiment of the present specification, L1 to L4 are divalent thiophene groups, respectively.

In one embodiment of the present specification, L1 to L4 each represent a divalent selenophene group.

In one embodiment of the present specification, Chemical Formula 1 may be represented by any one of the following Chemical Formulas 2-1 to 2-3.

[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

In Chemical Formulas 2-1 to 2-3,

R1 to R8, Ra to Rf, Y1, Y2, m and n are the same as defined in the formula (1).

In one embodiment of the present specification, Y1 and Y2 are each hydrogen.

In one embodiment of the present specification, Y1 and Y2 are each a linear alkyl group having 1 to 10 carbon atoms.

In one embodiment of the present specification, Y1 and Y2 are each a methyl group.

In one embodiment of the present specification, Y1 and Y2 are each fluorine.

In one embodiment of the present specification, n and m are each an integer of 0 to 2.

In one embodiment of the present specification, n and m are each 1.

In one embodiment of the present specification, n and m are each 2.

In one embodiment of the present specification, R1 to R4 are each a substituted or unsubstituted alkyl group.

In one embodiment of the present specification, R1 to R4 are each a linear or branched alkyl group having 1 to 30 carbon atoms.

In one embodiment of the present specification, R1 to R4 are each a linear or branched alkyl group having 1 to 20 carbon atoms.

In one embodiment of the present specification, R1 to R4 are each a linear or branched alkyl group having 1 to 10 carbon atoms.

In one embodiment of the present specification, R1 to R4 are each a linear alkyl group having 1 to 10 carbon atoms.

In one embodiment of the present specification, R1 to R4 are each hexyl group.

In one embodiment of the present specification, R5 to R8 are each hydrogen.

In one embodiment of the present specification, Ra to Rf are alkyl groups having 1 to 30 carbon atoms.

In one embodiment of the present specification, Ra to Rf are alkyl groups having 1 to 20 carbon atoms.

In one embodiment of the present specification, Ra to Rf are alkyl groups having 1 to 10 carbon atoms.

In one embodiment of the present specification, Ra to Rf are propyl groups.

In one embodiment of the present specification, Ra to Rf are isopropyl groups.

In one embodiment of the present specification, Chemical Formula 1 may be represented by the following Chemical Formulas 3-1 to 3-15.

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

[Formula 3-4]

[Formula 3-5]

[Formula 3-6]

[Formula 3-7]

[Formula 3-8]

[Formula 3-9]

[Formula 3-10]

[Formula 3-11]

[Formula 3-12]

[Formula 3-13]

[Formula 3-14]

[Formula 3-15]

In one embodiment of the present specification, the heterocyclic compound represents an absorption region of 300 nm to 1,000 nm, and preferably has a maximum absorption wavelength at 700 nm to 900 nm.

Accordingly, when applied to an organic electronic device, it exhibits absorption that is complementary to the absorption region (300 nm to 700 nm) of the electron donor, and thus may exhibit a high short circuit current when applied to the organic electronic device.

In one embodiment of the present specification, the compound is capable of absorbing light in the visible light wave field region and may also absorb light in the infrared region. Accordingly, the absorption wavelength range of the device can exhibit a wide effect.

An exemplary embodiment of the present specification includes a first electrode; A second electrode provided to face the first electrode; And one or more organic material layers provided between the first electrode and the second electrode and including an organic active layer, wherein the organic active layer includes the heterocyclic compound.

In addition, an exemplary embodiment of the present specification comprises the steps of forming a first electrode on a substrate; Forming an electron transport layer on the first electrode; Forming at least one organic material layer including an organic active layer on the electron transport layer; And forming a second electrode on the organic material layer, wherein the organic active layer comprises the heterocyclic compound.

In one embodiment of the present specification, the step of forming one or more organic material layers including the organic active layer is performed by a spin-coating method, the spin-coating speed may be 700rpm to 1,300rpm. .

When the speed of the spin-coating is in the above range, the thickness of the organic active layer is formed to about 100nm can be improved the performance of the organic electronic device.

The organic electronic device of the present invention may be manufactured by a conventional method and material for manufacturing an organic electronic device, except that the heterocyclic compound represented by Chemical Formula 1 is included in the organic active layer.

In one embodiment of the present specification, the organic active layer includes an electron donor and an electron acceptor, and the electron acceptor includes the heterocyclic compound.

In the present specification, the organic active layer may be a photoactive layer or a light emitting layer.

In the present specification, the organic electronic device may be an organic solar cell, an organic photoelectric device, an organic light emitting device, an organic photoconductor (OPC), or an organic transistor.

Hereinafter, it demonstrates about an organic solar cell. In the organic solar cell, the organic active layer is a photoactive layer, and the organic electronic device described above may refer to a description of the organic solar cell described below.

An exemplary embodiment of the present specification includes a first electrode; A second electrode provided to face the first electrode; And one or more organic material layers provided between the first electrode and the second electrode and including a photoactive layer, wherein the photoactive layer includes the heterocyclic compound.

The organic solar cell may further include a substrate, a hole transport layer, a hole injection layer, an electron injection layer and / or an electron transport layer.

In one embodiment of the present specification, the organic solar cell may further include an additional organic material layer. The organic solar cell may reduce the number of organic material layers by using an organic material having several functions at the same time.

In one embodiment of the present specification, the photoactive layer includes an electron donor and an electron acceptor, and the electron acceptor includes the heterocyclic compound.

In one embodiment of the present specification, the electron donor may use a material applied in the art, for example, poly 3-hexyl thiophene (P3HT: poly 3-hexyl thiophene), PCDTBT (poly [N-9 '-heptadecanyl-2,7-carbazole-alt-5,5- (4'-7'-di-2-thienyl-2', 1 ', 3'-benzothiadiazole)]), PCPDTBT (poly [2,6 -(4,4-bis- (2-ethylhexyl) -4H-cyclopenta [2,1-b; 3,4-b '] dithiophene) -alt-4,7- (2,1,3-benzothiadiazole)] ), PFO-DBT (poly [2,7- (9,9-dioctylfluorene) -alt-5,5- (4,7-bis (thiophene-2-yl) benzo-2,1,3-thiadiazole)] ), PTB7 (Poly [[4,8-bis [(2-ethylhexyl) oxy] benzo [1,2-b: 4,5-b '] dithiophene-2,6-diyl] [3-fluoro-2- [(2-ethylhexyl) carbonyl] thieno [3,4-b] thiophenediyl]]), PSiF-DBT (Poly [2,7- (9,9-dioctyl-dibenzosilole) -alt-4,7-bis (thiophen) -2-yl) benzo-2,1,3-thiadiazole]), PTB7-Th (Poly [4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2-b; 4,5-b '] dithiophene-2,6-diyl-alt- (4- (2-ethylhexyl) -3-fluorothieno [3,4-b] thiophene-)-2-carboxylate-2-6-diyl) ]) And PBDB-T (poly (benzodithiophene-benzotriazole) Eojin it may include one or more materials selected from the group.

In one embodiment of the present specification, the electron donor is PBDB-T. The mass ratio of the electron donor and the electron acceptor may be 1: 2 to 2: 1, preferably 1: 1.5 to 1.5: 1, more preferably 1: 1.

In one embodiment of the present specification, the electron donor and the electron acceptor may constitute a bulk hetero junction (BHJ). Bulk heterojunction means that the electron donor material and the electron acceptor material are mixed with each other in the photoactive layer.

In one embodiment of the present specification, the electron donor may be a p-type organic compound layer, and the electron acceptor may be an n-type organic compound layer.

In one embodiment of the present specification, the first electrode is an anode, and the second electrode is a cathode. In another exemplary embodiment, the first electrode is a cathode and the second electrode is an anode.

In another exemplary embodiment, the organic solar cell may be arranged in order of an anode, a hole transport layer, a photoactive layer, an electron transport layer, and a cathode, or may be arranged in the order of a cathode, an electron transport layer, a photoactive layer, a hole transport layer, and an anode. It is not limited to this.

In one embodiment of the present specification, the organic solar cell has a normal structure. In the normal structure, a substrate, a first electrode, a hole transport layer, an organic material layer including a photoactive layer, an electron transport layer, and a second electrode may be stacked in this order.

In one embodiment of the present specification, the organic solar cell has an inverted structure. In the inverted structure, a substrate, a first electrode, an electron transport layer, an organic material layer including a photoactive layer, a hole transport layer, and a second electrode may be stacked in this order.

1 illustrates an organic solar cell 100 according to an exemplary embodiment of the present specification. According to FIG. 1, in the organic solar device 100, when light is incident from the side of the first electrode 101 and / or the second electrode 105, and the photoactive layer 103 absorbs light in the entire wavelength region, excitons are formed therein. Can be generated. The exciton is separated into holes and electrons in the photoactive layer 103, and the separated holes move to the anode side, which is one of the first electrode 101 and the second electrode 105, and the separated electrons are separated from the first electrode 101. The current flows to the organic solar cell by moving to the cathode side, which is the other one of the second electrodes 105.

In one embodiment of the present specification, the organic solar cell has a tandem structure. In this case, the organic solar cell may include two or more photoactive layers.

In the organic solar cell according to the exemplary embodiment of the present specification, the photoactive layer may be one layer or two or more layers.

In another exemplary embodiment, a buffer layer may be provided between the photoactive layer and the hole transport layer or between the photoactive layer and the electron transport layer. In this case, a hole injection layer may be further provided between the anode and the hole transport layer. In addition, an electron injection layer may be further provided between the cathode and the electron transport layer.

In an exemplary embodiment of the present specification, 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 limited to any substrate commonly used in organic solar cells. It doesn't work. Specifically, there are glass, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polypropylene (PP), polyimide (PI), and triacetyl cellulose (TAC). It is not limited to this.

The material of the first electrode may be a transparent and excellent conductive material, but is not limited thereto. Metals such as vanadium, chromium, copper, zinc, gold or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO); Combinations of metals and oxides such as ZnO: Al or SnO ₂ : Sb; And conductive polymers such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDOT), polypyrrole and polyaniline, and the like, but are not limited thereto. .

The method of forming the first electrode is not particularly limited, and for example, sputtering, E-beam, thermal deposition, spin coating, screen printing, inkjet printing, doctor blade, or gravure printing may be used.

When the first electrode is formed on the substrate, it may be subjected to cleaning, moisture removal, and hydrophilic modification.

For example, the patterned ITO substrate is sequentially cleaned with a detergent, acetone, and isopropyl alcohol (IPA), and then 1 to 30 minutes at 100 ° C. to 150 ° C., preferably at 120 ° C. for 10 minutes on a heating plate to remove moisture. When the substrate is dried and thoroughly cleaned, the surface of the substrate is modified to be hydrophilic.

Through such surface modification, the bonding surface potential can be maintained at a level suitable for the surface potential of the photoactive layer. In addition, it is easy to form the polymer thin film on the first electrode during modification, the quality of the thin film may be improved.

Pretreatment techniques for the first electrode include a) surface oxidation using parallel plate discharge, b) oxidation of the surface through ozone generated using UV ultraviolet light in a vacuum state, and c) oxygen generated by plasma. And oxidation using radicals.

One of the above methods can be selected according to the state of the first electrode or the substrate. In any case, however, it is preferable to prevent oxygen escape from the surface of the first electrode or the substrate and to minimize the residual of moisture and organic matter in common. At this time, the substantial effect of the pretreatment can be maximized.

As a specific example, a method of oxidizing a surface through ozone generated using UV may be used. At this time, after ultrasonic cleaning, the patterned ITO substrate is baked on a hot plate, dried well, then put into a chamber, and a UV lamp is activated to cause oxygen gas to react with UV light. The patterned ITO substrate can be cleaned.

However, the surface modification method of the patterned ITO substrate in this specification does not need to be specifically limited, Any method may be used as long as it is a method of oxidizing a substrate.

The second electrode may be a metal having a small work function, but is not limited thereto. Specifically, metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead or alloys thereof; Or a material having a multilayer structure such as LiF / Al, LiO ₂ / Al, LiF / Fe, Al: Li, Al: BaF ₂ , Al: BaF ₂ : Ba, but is not limited thereto.

The second electrode may be formed by being deposited in a thermal evaporator having a vacuum degree of 5 × 10 ⁻⁷ torr or less, but is not limited thereto.

The hole transport layer and / or electron transport layer material plays a role of efficiently transferring electrons and holes separated in the photoactive layer to the electrode, and the material is not particularly limited.

The hole transport layer material may be PEDOT: PSS (Poly (3,4-ethylenediocythiophene) doped with poly (styrenesulfonic acid)), molybdenum oxide (MoO _x ); Vanadium oxide (V ₂ O ₅ ); Nickel oxide (NiO); Tungsten oxide (WO _x ), and the like, but is not limited thereto.

The electron transport layer material may be BCP (bathocuproine) or electron extraction metal oxides (electron-extracting metal oxides), specifically, BCP (bathocuproine), metal complex of 8-hydroxyquinoline; Complexes including Alq ₃ ; Metal complexes including Liq; LiF; Ca; Titanium oxide (TiO _x ); Zinc oxide (ZnO); And cesium carbonate (Cs ₂ CO ₃ ), and the like, but is not limited thereto.

In one embodiment of the present specification, the method of forming the photoactive layer may be a vacuum deposition method or a solution coating method, and the solution coating method is a photoactive material such as an electron donor and / or an electron acceptor to an organic solvent. After dissolution, a solution is applied by spin coating, dip coating, screen printing, spray coating, doctor blade and brush painting, but is not limited thereto.

Compounds according to one embodiment of the present specification may be prepared by the production method described below. In the following production examples, representative examples are described, but if necessary, a substituent may be added or excluded, and the position of the substituent may be changed. In addition, based on techniques known in the art, it is possible to change the starting materials, reactants and reaction conditions and the like.

In addition, the present invention will be described in detail with reference to Examples. However, the embodiments according to the present disclosure may be modified in various other forms, and the scope of the present specification is not to be interpreted as being limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

Preparation Example: Synthesis of Compounds 1 to 15

Preparation Example 1 Preparation of Compounds 1 to 5

(1) Preparation of Compound A

In a round flask equipped with a condenser ((2,6-bis (trimethylstannyl) benzo [1,2-b: 4,5-b '] dithiophene-4,8-diyl) bis (ethyne-2,1-diyl) 5 g of bis (triisopropylsilane) was dissolved in 150 mL of toluene with 0.43 g of Pd ₂ (dba) ₃ and 0.57 g of tri (o-tolyl) phosphine. When the temperature reached 100 ° C, 5.15 g (2.5eq) of ethyl 2-bromothiophene-3-carboxylate was dissolved in 5 mL of toluene, and slowly injected, and refluxed for 12 hours. After the reaction was completed, Compound A (diethyl 2,2 '-(4,8-bis ((triisopropylsilyl) ethynyl) benzo [1,2-b: 4,5-b'] dithiophene- was purified through column chromatography. 2,6-diyl) bis (thiophene-3-carboxylate)) was obtained.

(2) Preparation of Compound B

Dissolve 8.16g (5.3eq) of 1-bromo-4-hexylbenzene in THF 200mL in a round flask and slowly inject 13.5mL of n-BuLi at -78 ℃ for 1 hour. Stir at the same temperature. Compound A prepared in (1) was dissolved in THF 50mL, and slowly injected into a stirring round flask, followed by stirring at room temperature for 12 hours. After extracting the organic layer through chloroform, the solvent was removed, dissolved in 100 mL of octane, 10 mL of acetic acid and 1 mL of sulfuric acid, and then refluxed at 65 ° C. for 4 hours. The reaction was terminated through distilled water and Compound B was obtained through column chromatography.

(3) Preparation of Compound C

In a round flask, 1 g of Compound B prepared in (2) was dissolved in 100 mL of THF, and 0.76 mL of n-BuLi was slowly injected at -78 ° C. After stirring at the same temperature for 1 hour, 0.5 mL of DMF was slowly injected and stirred for 12 hours. After the reaction was completed through distilled water, the organic layer was extracted, and then Compound C was obtained through column chromatography.

(4) Preparation of Compound 1

In a round flask equipped with a condenser, 1 g of compound C prepared in (3) and 2- (3-oxo-2,3-dihydro-1H-indene-1-ylidene) malononitrile (2- (3- 0.7 g of oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile) was dissolved in 10 mL of chloroform, 1 mL of pyridine was injected, and refluxed at 60 ° C. for 12 hours. Compound 1 was obtained through column chromatography after filtration through methanol.

UV-Vis spectrum of the film state of the prepared compound 1 is shown in FIG.

(5) Preparation of Compounds 2-5

2- (3-oxo-2,3-dihydro-1H-indene-1-ylidene) malononitrile (2- (3-oxo-2,3-dihydro-1H-inden-1) in the above (4) -Ylidene) malononitrile) The same procedure as in (4) except that the material of Table 1, respectively, instead of using the following compounds 2 to 5 were prepared.

Target compound Used materials Compound 2 2- (6-fluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile and 2- (5-fluoro-3-oxo-2,3-dihydro-1H-inden-1- ylidene) malononitrile mixed in a mass ratio of 3: 7 Compound 3 (2- (5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile) Compound 4 2- (6-methyl-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile and 2- (5-methyl-3-oxo-2,3-dihydro-1H-inden-1- ylidene) malononitrile mixed in a mass ratio of 3: 7 Compound 5 2- (5,6-dimethyl-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile

[Compound 2]

[Compound 3]

[Compound 4]

[Compound 5]

Preparation Example 2 Preparation of Compounds 6 to 10

(1) Preparation of Compound B2

Preparation Example 1 (2) except that 2-hexylthiophene (2-hexylthiophene) instead of 1-bromo-4-hexylbenzene in (2) of Preparation Example 1 Compound B2 was prepared by the same process as).

(2) Preparation of Compound C2

Compound C2 was prepared in the same manner as in (3) of Preparation Example 1, except that Compound B2 was used instead of Compound B in Preparation Example 1 (3).

(3) Preparation of Compound 6

Compound 6 was prepared in the same manner as in (4) of Preparation Example 1, except that Compound C2 was used instead of Compound C in Preparation Example 1 (4).

(4) Preparation of Compounds 7 to 10

2- (3-oxo-2,3-dihydro-1H-indene-1-ylidene) malononitrile (2- (3-oxo-2,3-dihydro-1H in Preparation Example 2) -Inden-1-ylidene) malononitrile) The same procedure as in (3) of Preparation Example 2 except for using the materials shown in Table 2, respectively, to prepare the following compounds 7 to 10.

Target compound Used materials Compound 7 2- (6-fluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile and 2- (5-fluoro-3-oxo-2,3-dihydro-1H-inden-1- ylidene) malononitrile mixed in a mass ratio of 3: 7 Compound 8 (2- (5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile) Compound 9 2- (6-methyl-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile and 2- (5-methyl-3-oxo-2,3-dihydro-1H-inden-1- ylidene) malononitrile mixed in a mass ratio of 3: 7 Compound 10 2- (5,6-dimethyl-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile

[Compound 7]

[Compound 8]

[Compound 9]

[Compound 10]

Preparation Example 3 Synthesis of Compounds 11 to 15

(1) Preparation of Compound B3

Except for using 1-bromo-3-hexylbenzene instead of 1-bromo-4-hexylbenzene in (2) of Preparation Example 1 Compound B3 was prepared in the same manner as in (2) of Preparation Example 1.

(2) Preparation of Compound C3

Compound C3 was prepared in the same manner as in (3) of Preparation Example 1, except that Compound B3 was used instead of Compound B in Preparation Example 1 (3).

(3) Preparation of Compound 11

Compound 11 was prepared in the same manner as in (4) of Preparation Example 1, except that Compound C3 was used instead of Compound C in Preparation Example 1 (4).

(4) Preparation of Compounds 12-15

2- (3-oxo-2,3-dihydro-1H-indene-1-ylidene) malononitrile (2- (3-oxo-2,3-dihydro-1H) in (3) of Preparation Example 3 -Inden-1-ylidene) malononitrile) was prepared in the same manner as in (3) of the Preparation Example 3 except for using the materials shown in Table 3, respectively, to prepare the compounds 12 to 15.

Target compound Used materials Compound 12 2- (6-fluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile and 2- (5-fluoro-3-oxo-2,3-dihydro-1H-inden-1- ylidene) malononitrile mixed in a mass ratio of 3: 7 Compound 13 (2- (5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile) Compound 14 2- (6-methyl-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile and 2- (5-methyl-3-oxo-2,3-dihydro-1H-inden-1- ylidene) malononitrile mixed in a mass ratio of 3: 7 Compound 15 2- (5,6-dimethyl-3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile

[Compound 12]

[Compound 13]

[Compound 14]

[Compound 15]

Example: Fabrication of Organic Solar Cell

Example 1.

(1) Preparation of Complex Solution

The following compound poly [(2,6- (4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) -benzo [1,2-b: 4,5-b '] dithiophene) ) -Alt- (5,5- (1 ', 3'-di-2-thienyl-5', 7'-bis (2-ethylhexyl) benzo [1 ', 2'-c: 4', 5 '-c'] dithiophene-4,8-dione))] (poly [(2,6- (4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) -benzo [1, 2-b: 4,5-b '] dithiophene))-alt- (5,5- (1', 3'-di-2-thienyl-5 ', 7'-bis (2-ethylhexyl) benzo [1 ', 2'-c: 4', 5'-c '] dithiophene-4,8-dione))], PBDB-T) (Mn: 25,000g / mol, Solarmer) as the electron donor material Compound 1 synthesized in the example was dissolved in chlorobenzene (Chlorobenzene, CB) in a mass ratio of 1: 1 using an electron acceptor to prepare a composite solution having a concentration of 2wt%.

(2) Preparation of Organic Solar Cell

A glass substrate coated with a bar type of 1.5 × 1.5 cm ² (11.5Ω / □) was ultrasonically cleaned using distilled water, acetone, and 2-propanol, and the surface of the ITO was ozone treated for 10 minutes. One electrode was formed.

After spin-coating a ZnO nanoparticle solution (N-10, Nanograde Ltd, 2.5 wt% in 1-butanol, filtered to 0.45 μm PTFE) on the first electrode for 40 seconds at 4,000 rpm, The electron transport layer was formed by removing the remaining solvent by heat treatment at 80 ℃ for 10 minutes.

Thereafter, the composite solution prepared in (1) was spin-coated on the electron transport layer at 70 ° C. at 700 rpm for 25 seconds to form a photoactive layer, and MoO ₃ on the photoactive layer at a rate of 0.2 Å / s and 10 ^The hole transport layer was formed by thermal evaporation to a thickness of 10 nm under ^-7 torr vacuum.

Thereafter, Ag was deposited to a thickness of 100 nm at a rate of 1 dB / s inside the thermal evaporator to form a second electrode, thereby manufacturing an organic solar cell having an inverted structure.

Example 2.

An organic solar cell was manufactured in the same manner as in Example 1, except that the composite solution prepared in (1) was spin-coated at 900 rpm when the photoactive layer was formed in Example 1.

Example 3.

An organic solar cell was manufactured in the same manner as in Example 1, except that the composite solution prepared in (1) was spin-coated at 1,100 rpm when the photoactive layer was formed in Example 1.

Example 4.

An organic solar cell was manufactured in the same manner as in Example 1, except that the composite solution prepared in (1) was spin-coated at 1,300 rpm when the photoactive layer was formed in Example 1.

Comparative Example 1.

In preparing the complex solution in Example 1, an organic solar cell was manufactured in the same manner as in Example 1, except that Comparative Compound 1 was used instead of Compound 1.

Comparative Compound 1

Comparative Example 2.

An organic solar cell was manufactured in the same manner as in Comparative Example 1, except that the composite solution prepared in (1) was spin-coated at 900 rpm when the photoactive layer was formed in Comparative Example 1.

Comparative Example 3.

An organic solar cell was manufactured in the same manner as in Comparative Example 1, except that the composite solution prepared in (1) was spin-coated at 1,100 rpm when the photoactive layer was formed in Comparative Example 1.

Comparative Example 4.

An organic solar cell was manufactured in the same manner as in Comparative Example 1, except that the composite solution prepared in (1) was spin-coated at 1,300 rpm when the photoactive layer was formed in Comparative Example 1.

The photoelectric conversion characteristics of the organic solar cells prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were measured under 100 mW / cm ² (AM 1.5), and the results are shown in Table 4 below.

Spin-speed (rpm) V _oc
(V) J _sc
(mA / cm ² ) FF η
(%) Average η
(%) PBDB-T + Compound 1 Example
One 700 0.919 17.032 0.580 9.07 8.85 0.916 16.628 0.566 8.63 Example
2 900 0.925 17.168 0.629 9.98 10.07 0.924 17.202 0.639 10.16 Example
3 1,100 0.926 16.502 0.650 9.94 9.90 0.924 16.372 0.652 9.86 Example
4 1,300 0.910 16.053 0.644 9.40 9.09 0.901 15.766 0.618 8.78 PBDB-T + Comparative Compound 1 Comparative example
One 700 0.739 17.869 0.523 6.91 6.91 0.736 17.932 0.522 6.90 Comparative example
2 900 0.733 18.340 0.568 7.63 7.63 0.729 18.552 0.564 7.62 Comparative example
3 1,100 0.750 17.323 0.605 7.86 7.87 0.746 17.627 0.598 7.87 Comparative example
4 1,300 0.744 16.563 0.616 7.59 7.72 0.748 16.596 0.632 7.84

In Table 4, the spin-speed is the rotational speed of the equipment when forming the photoactive layer by spin-coating the composite solution on the electron transport layer, V _OC is the open voltage, J _SC is the short-circuit current, FF is the charge rate (Fill factor), η means energy conversion efficiency. The open-circuit and short-circuit currents are the X- and Y-axis intercepts in the four quadrants of the voltage-current density curve, respectively. The higher these two values, the higher the efficiency of the solar cell. Also, the fill factor is the area of the rectangle drawn inside the curve divided by the product of the short circuit current and the open voltage. The energy conversion efficiency η can be obtained by dividing the product of the open voltage V _oc , the short-circuit current J _sc and the charging rate FF by the intensity P _in of the incident light, and higher values are preferred. .

Looking at the results of Table 4, the organic solar cells of Examples 1 to 4 using the compound 1 according to an embodiment of the present disclosure as an electron acceptor compared to the organic solar cells of Comparative Examples 1 to 4 using the comparative compound It turns out that this is high, and element efficiency, such as a charge rate, is excellent and energy conversion efficiency is excellent. Specifically, in the case of the organic solar cell using the compound according to one embodiment of the present specification, the energy conversion efficiency was measured to 8% or more, preferably 9% or more.

In addition, Figure 2 is a graph showing the film state UV-Vis absorption spectrum of the compound 1, PBDB-T and the comparative compound, compound 1 according to an exemplary embodiment of the present specification is red-shifted compared to the comparative compound 1 It can be seen that the tendency is). This tendency can be seen that the compound 1 is due to the increased planarity compared to the comparative compound by the introduction of acetylene, and consequently contribute to high FF can lead to excellent energy conversion efficiency.

Claims (10)

Heterocyclic compound represented by the formula (1):
[Formula 1]

In Chemical Formula 1,
R1 to R8 are each hydrogen; Or a substituted or unsubstituted alkyl group,
Ra to Rf are each hydrogen; Substituted or unsubstituted alkyl group; Or a substituted or unsubstituted aryl group,
L1 to L4 each represent a substituted or unsubstituted arylene group; Or a substituted or unsubstituted divalent heterocyclic group,
Y1 and Y2 are each hydrogen; Substituted or unsubstituted alkyl group; Or a halogen group,
m and n are each an integer of 0-4. The method according to claim 1,
Formula 1 is a heterocyclic compound represented by any one of the following formulas 2-1 to 2-3:
[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

In Chemical Formulas 2-1 to 2-3,
R1 to R8, Ra to Rf, Y1, Y2, m and n are the same as defined in the formula (1). The method according to claim 1,
Y1 and Y2 are each hydrogen; Methyl group; Or fluorine. The method according to claim 1,
Ra to Rf is a heterocyclic compound which is an alkyl group having 1 to 30 carbon atoms. The method according to claim 1,
Formula 1 is a heterocyclic compound which is any one selected from formulas 3-1 to 3-15:
[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

[Formula 3-4]

[Formula 3-5]

[Formula 3-6]

[Formula 3-7]

[Formula 3-8]

[Formula 3-9]

[Formula 3-10]

[Formula 3-11]

[Formula 3-12]

[Formula 3-13]

[Formula 3-14]

[Formula 3-15]

A first electrode;
A second electrode provided to face the first electrode; And
It is provided between the first electrode and the second electrode, and includes one or more organic material layer including an organic active layer,
The organic active layer is an organic electronic device comprising a heterocyclic compound according to any one of claims 1 to 5. The method according to claim 6,
The organic active layer includes an electron donor and an electron acceptor,
The electron acceptor is an organic electronic device comprising the heterocyclic compound. The method according to claim 6,
The organic electronic device is an organic solar cell, an organic photoelectric device, an organic light emitting device, an organic photosensitive member or an organic transistor. Forming a first electrode on the substrate;
Forming an electron transport layer on the first electrode;
Forming at least one organic material layer including an organic active layer on the electron transport layer; And
Forming a second electrode on the organic material layer;
The organic active layer is a method for producing an organic electronic device comprising the heterocyclic compound according to any one of claims 1 to 5. The method according to claim 9,
Forming at least one organic material layer including an organic active layer on the electron transport layer is performed by a spin-coating method,
The spin-coating speed is 700rpm to 1,300rpm manufacturing method of an organic electronic device.

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