KR20200043092A - Copolymer and electronic device comprising the same - Google Patents

Abstract

The present specification provides a copolymer comprising a conjugated monomer and a unit represented by formula 1, and an organic solar cell including the same. The copolymer has a clear molecular structure, and thus is excellent in reproducing synthesis.

Description

Copolymer and organic electronic device comprising the same TECHNICAL FIELD

The present specification relates to a copolymer and an organic electronic device including the same.

An organic electronic device means a device that requires charge exchange between an electrode and organic materials using holes and / or electrons. Organic electronic devices can be roughly divided into two types according to the operating principle. First, excitons are formed in the organic layer by photons introduced into the device from an external light source, the excitons are separated into electrons and holes, and the electrons and holes are transferred to different electrodes to be used as a current source (voltage source). It is a form of electric device. The second is an electronic device in which holes and / or electrons are injected into an organic semiconductor that forms an interface with an electrode by applying voltage or current to two or more electrodes, and operated by the injected electrons and holes.

Examples of the organic electronic device include an organic photodiode, an organic light emitting device, an organic solar cell, an organic transistor, etc. Hereinafter, mainly an organic solar cell will be described in detail, but electron injection or transport material, or a principle similar to the light emitting material Acts as

An organic solar cell is a device that can directly convert solar energy into electrical energy by applying a photovoltaic effect. The solar cell may be divided into an inorganic solar cell and an organic solar cell according to the materials constituting the thin film. A typical solar cell is made of a p-n junction by doping crystalline silicon (Si), an inorganic semiconductor. The electrons and holes generated by absorbing light diffuse to the p-n junction and accelerate by the electric field to move to the electrode. The power conversion efficiency of this process is defined as the ratio of the power supplied to the external circuit to the solar power entering the solar cell, and has been achieved up to 24% when measured under the standardized virtual solar irradiation conditions. However, since conventional inorganic solar cells have already shown limitations in economical and material supply and demand, organic semiconductor solar cells that are easy to process and have various functions have been spotlighted as long-term alternative energy sources.

It is important to increase efficiency so that the solar cell can output as much electrical energy as possible from solar energy. In order to increase the efficiency of such a solar cell, it is important to generate as many excitons as possible inside the semiconductor, but it is also important to draw the generated charge to the outside without loss. One of the causes of the loss of charge is that the generated electrons and holes are destroyed by recombination. Various methods have been proposed as a method for transferring the generated electrons or holes without being lost to the electrode, but most of them require an additional process and accordingly the manufacturing cost may increase.

Two-layer organic photovoltaic cell (C.W.Tang, Appl.Phys. Lett., 48, 183. (1986))

The present specification provides a copolymer and an organic electronic device including the same.

An exemplary embodiment of the present specification is a unit represented by the following formula (1); And

It provides a copolymer comprising a conjugated monomer.

[Formula 1]

In Chemical Formula 1,

X1 to X3 are the same as or different from each other, and each independently CRR ', NR, O, SiRR', PR, S, GeRR ', Se or Te,

R1 to R8, R and R 'are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

Another exemplary embodiment of the present specification is a first electrode;

A second electrode provided to face the first electrode; And

An organic electronic device including at least one organic layer provided between the first electrode and the second electrode,

At least one layer of the organic material layer provides an organic electronic device comprising the copolymer.

Unlike the random copolymer, the copolymer according to an exemplary embodiment of the present specification is formed through alternating polymerization, so that the molecular structure is clear and the synthetic reproducibility is excellent.

The copolymer according to an exemplary embodiment of the present specification has an asymmetricality even though it is an alternating copolymer, and thus has excellent solubility and viscosity, which is advantageous for a solution process, and thus has economical advantages in terms of time and / or cost when manufacturing a device.

The copolymer according to the exemplary embodiment of the present specification may exhibit high current value (Jsc) and excellent efficiency when applied to an organic solar cell.

The compound according to the exemplary embodiment of the present specification may be used alone or in combination with other materials in an organic solar cell.

1 is a view showing an organic electronic device according to an exemplary embodiment of the present specification.
2 is a view showing an organic solar cell according to an exemplary embodiment of the present specification.
3 is a diagram showing the results of MS measurement of compound a-2.
4 is a diagram showing the results of NMR measurement of compound a-2.
5 is a diagram showing the results of MS measurement of compound a-4.
6 is a diagram showing the results of NMR measurement of compound a-4.
7 is a diagram showing the results of MS measurement of compound a-5.
8 is a DSC measurement result of copolymer 1-2.

Hereinafter, this specification will be described in detail.

An exemplary embodiment of the present specification is a unit represented by the formula (1); And it provides a copolymer comprising a conjugated monomer.

In the present specification, "unit" means a repeating structure included in the copolymer. That is, "unit" may mean a structure included in the form of a divalent or more group in the copolymer by a polymerization reaction.

In the present specification, the meaning of “comprising a unit” means being included in the main chain in the copolymer.

In one embodiment of the present specification, the copolymer is alternately provided with a unit represented by Chemical Formula 1 and a conjugated monomer in the copolymer. That is, in one embodiment of the present specification, the copolymer is an alternating copolymer.

In the present specification, the “alternative copolymer” means that two units are sequentially and repeatedly provided in the copolymer. For example, when the unit represented by Formula 1 is A and the conjugated monomer is B, it means that the -ABAB- structure is continuously repeated.

In one embodiment of the present specification, the unit represented by Chemical Formula 1 may be provided by rotating left and right and / or up and down in the copolymer. For example, the unit represented by Formula 1 may be provided in two forms as follows in the copolymer.

In one embodiment of the present specification, even if the unit represented by Chemical Formula 1 is provided by rotating left and / or up and down as described above, one type is used as a monomer for making the unit represented by Chemical Formula 1. Accordingly, regardless of the type of the unit represented by Formula 1 in the copolymer, if the unit represented by Formula 1 and the conjugated monomer are sequentially and repeatedly provided, it can be said to be an alternating copolymer.

In one embodiment of the present specification, the copolymer includes a structure represented by Formula 2 below.

[Formula 2]

In Chemical Formula 2,

f is the molar fraction, and is a real number with 0 <f <1,

g is the molar fraction, and is a real number with 0 <g <1,

f + g = 1,

n is an integer from 1 to 10,000,

E is a conjugated monomer,

X1 to X3 are the same as or different from each other, and each independently CRR ', NR, O, SiRR', PR, S, GeRR ', Se or Te,

R1 to R8, R and R 'are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In an exemplary embodiment of the present specification, the Chemical Formula 2 has an asymmetric structure because the upper and lower and / or left and right of the unit represented by the Chemical Formula 1 are rotated.

In one embodiment of the present specification, the formula (2) is an alternating copolymer because the unit represented by the formula (1) and the conjugated monomer (E) are alternately provided in sequence.

In one embodiment of the present specification, the copolymer is an alternating copolymer while exhibiting an asymmetric structure. Accordingly, the copolymer can simultaneously exhibit the advantages of the asymmetric structure and the advantages of the alternating copolymer. For example, since the copolymer is an alternating copolymer, its molecular structure is well-defined, its synthetic reproducibility is high, and its asymmetric structure improves solubility.

In one embodiment of the present specification, f is a molar fraction, a real number of 0.3 <f <0.7, g is a molar fraction, a real number of 0.3 <g <0.7, and f + g is 1.

In one embodiment of the present specification, when the unit represented by Formula 1 is A, the conjugate monomer is B, and the unit represented by Formula 1 is rotated left and right and / or up and down is called A ', the aerial In the coalescence, the first unit represented by -AB- and the second unit represented by -A'B- are mixed. That is, the copolymer is provided with the first unit and the second unit mixed, and the -AB- structure is a repeating asymmetric alternating copolymer.

In one embodiment of the present specification, the copolymer includes a structure represented by Formula 3 below.

[Formula 3]

In Chemical Formula 3,

n is an integer from 1 to 10,000,

E is a conjugated monomer,

X1 to X3 are the same as or different from each other, and each independently CRR ', NR, O, SiRR', PR, S, GeRR ', Se or Te,

R1 to R8, R and R 'are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present specification, the copolymer represented by Chemical Formula 3 has a block copolymer form.

In the present specification, the “block copolymer” means that the same units in the copolymer are connected by block. For example, when the unit represented by the formula (1) is A, the conjugate monomer is B. When the unit provided by rotating the left and right and / or up and down is represented by A ', -'ABA'B]-[ABA 'B]-means that the structure is continuously repeated.

In one embodiment of the present specification, the block copolymer is formed due to a difference in reactivity between asymmetric monomers.

In an exemplary embodiment of the present specification, when the R1 causes a conjugated monomer and steric hindrance, the copolymer is formed of a block copolymer. For example, when R1 is 2 or more carbons, not hydrogen, the copolymer is formed of a block copolymer.

In one embodiment of the present specification, the copolymer includes a structure represented by Formula 2 (asymmetric alternating copolymer) or Formula 3 (block copolymer).

In one embodiment of the present specification, R1, R2, R5, and R6 are the same as or different from each other, and each independently hydrogen; Or a substituted or unsubstituted alkyl group.

In one embodiment of the present specification, R2, R5, and R6 are each hydrogen.

In one embodiment of the present specification, R3 and R4 are the same as or different from each other, and each independently hydrogen; Or a halogen group.

In one embodiment of the present specification, R4 is hydrogen.

In one embodiment of the present specification, Chemical Formula 3 is represented by the following Chemical Formula 3-1.

[Formula 3-1]

In Chemical Formula 3,

n is an integer from 1 to 10,000,

E1 and E2 are the same as each other, and each is a conjugated monomer,

X1 to X3 are the same as or different from each other, and each independently CRR ', NR, O, SiRR', PR, S, GeRR ', Se or Te,

R1 and R3 are the same as or different from each other, and each independently a halogen group; A substituted or unsubstituted alkyl group having 2 or more carbon atoms; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group,

R and R 'are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present specification, the copolymer represented by Chemical Formula 3-1 exhibits aromaticity.

In this specification, the "aromatic" means that a substituent is provided in a certain direction in the structure in the copolymer. For example, in Chemical Formula 3-1, R1 is substituted at a position relatively distant from R3, and R3 is substituted at a position relatively distant from E1.

In one embodiment of the present specification, the copolymer represented by Chemical Formula 3-1 is a block copolymer.

In an exemplary embodiment of the present specification, the copolymer represented by Chemical Formula 3-1 has a region-regular shape, and crystallinity is improved.

In an exemplary embodiment of the present specification, the unit represented by Chemical Formula 1 is represented by A. The Chemical Formula 1, but when the unit provided by rotating left and right and / or up and down is A ', is represented by Chemical Formula 3-1. The unit includes a section having directionality (section A-E1-A ') and a section not showing directionality (section E2) at the same time. Accordingly, it is possible to exhibit the properties of the thermoplastic elastomer due to the difference in properties between sections.

In one embodiment of the present specification, the copolymer includes a structure represented by Chemical Formula 2 (Landon Copolymer) or Chemical Formula 3-1 (Block Copolymer).

In one embodiment of the present specification, R1 and R3 are the same as or different from each other, and each independently a halogen group; Or a substituted or unsubstituted alkyl group having 2 to 30 carbon atoms; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present specification, the R1 and R3 are the same as or different from each other, and each independently a halogen group; Or a substituted or unsubstituted alkyl group having 2 to 30 carbon atoms.

In one embodiment of the present specification, R1 is a substituted or unsubstituted alkyl group having 5 to 30 carbon atoms.

In one embodiment of the present specification, R1 is a substituted or unsubstituted alkyl group having 10 to 30 carbon atoms.

In one embodiment of the present specification, R3 is a halogen group.

In one embodiment of the present specification, R3 is fluorine.

In one embodiment of the present specification, R7 and R8 are substituted or unsubstituted alkyl groups.

In one embodiment of the present specification, R7 and R8 are substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms.

는 다른 치환기, 단량체 또는 결합부에 결합되는 부위를 의미한다.In this specification,

Means a site bonded to another substituent, monomer or linkage.

Examples of substituents in the present specification are described below, but are not limited thereto.

In this specification, the term "substituted or unsubstituted" is deuterium; Halogen group; Alkyl groups; Cycloalkyl group; Alkenyl group; Alkoxy groups; Amine group; Aryl group; And one or two or more substituents selected from the group consisting of heterocyclic groups, or substituted with two or more substituents among the above-described substituents, or having no substituents.

In the present specification, the halogen group may be fluorine, chlorine, bromine or iodine.

In the present specification, the alkyl group may be straight chain or branched chain, and carbon number is not particularly limited, but is preferably 1 to 30. Specific examples are methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n-pentyl , Isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n -Heptyl, 1-methylhexyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 4-methylhexyl, 5-methylhexyl, and the like, but is not limited thereto.

In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 30 carbon atoms, specifically cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl , 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctyl, and the like. It does not work.

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

When the aryl group is a monocyclic aryl group, the number of carbon atoms is not particularly limited, but is preferably 6 to 30 carbon atoms. Specifically, the monocyclic aryl group may be a phenyl group, a biphenyl group, or a terphenyl group, but is not limited thereto.

When the aryl group is a polycyclic aryl group, the number of carbon atoms is not particularly limited. It is preferable that it has 10 to 30 carbon atoms. Specifically, the polycyclic aryl group may be a naphthyl group, anthracenyl group, phenanthryl group, pyrenyl group, perylenyl group, chrysenyl group, fluorenyl group, and the like, but is not limited thereto.

In the present specification, the heterocyclic group includes one or more non-carbon atoms, heteroatoms, and specifically, the heteroatoms may include one or more atoms selected from the group consisting of O, N, Se, and S. The number of carbon atoms is not particularly limited, but preferably 2 to 30 carbon atoms, and the heterocyclic group may be monocyclic or polycyclic. Examples of the heterocyclic group include thiophene group, furanyl group, pyrrol group, imidazolyl group, thiazolyl group, oxazolyl group, oxadiazolyl group, pyridyl group, bipyridyl group, pyrimidyl group, triazinyl group, tria Jolyl group, acridil group, pyridazinyl group, pyrazinyl group, quinolinyl group, quinazolinyl group, quinoxalinyl group, phthalazinyl group, pyridopyrimidyl group, pyridopyrazinyl group, pyrazino pyrazinyl group , Isoquinolinyl group, indolyl group, carbazolyl group, benzoxazolyl group, benzimidazolyl group, benzothiazolyl group, benzocarbazolyl group, benzothiophene group, dibenzothiophene group, benzofuranyl group, pe Nanthrolyl group (phenanthroline), thiazolyl group, isooxazolyl group, oxadiazolyl group, thiadiazolyl group, phenothiazinyl group, and dibenzofuranyl group, but are not limited thereto.

In the present specification, the alkenyl group may be straight chain or branched chain, and the number of carbon atoms is not particularly limited, but is preferably 2 to 30. Specific examples include vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 3-methyl-1- Butenyl, 1,3-butadienyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, 2,2-diphenylvinyl-1-yl, 2-phenyl-2- ( Naphthyl-1-yl) vinyl-1-yl, 2,2-bis (diphenyl-1-yl) vinyl-1-yl, styrenyl group, styrenyl group, and the like, but are not limited thereto.

In the present specification, the alkoxy group may be a straight chain, branched chain or cyclic chain. The number of carbon atoms of the alkoxy group is not particularly limited, but is preferably 1 to 30 carbon atoms. Specifically, methoxy, ethoxy, n-propoxy, isopropoxy, i-propyloxy, n-butoxy, isobutoxy, tert-butoxy, sec-butoxy, n-pentyloxy, neopentyloxy, Isopentyloxy, n-hexyloxy, 3,3-dimethylbutyloxy, 2-ethylbutyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, benzyloxy, p-methylbenzyloxy, etc. It may be, but is not limited to this.

In the present specification, the amine group is -NH ₂ ; Monoalkylamine groups; Dialkylamine groups; N-alkylarylamine group; Monoarylamine group; Diarylamine group; N-aryl heteroarylamine group; It may be selected from the group consisting of N-alkylheteroarylamine groups, monoheteroarylamine groups and diheteroarylamine groups, and the number of carbon atoms is not particularly limited, but is preferably 1 to 30. Specific examples of the amine group are methylamine group, dimethylamine group, ethylamine group, diethylamine group, phenylamine group, naphthylamine group, biphenylamine group, anthracenylamine group, 9-methyl-anthracenylamine group , Diphenylamine group, ditolylamine group, N-phenyltolylamine group, triphenylamine group, N-phenylbiphenylamine group; N-phenyl naphthylamine group; N-biphenyl naphthylamine group; N-naphthylfluorenylamine group; N-phenylphenanthrenylamine group; N-biphenylphenanthrenylamine group; N-phenylfluorenylamine group; N-phenyl terphenylamine group; N-phenanthrenylfluorenylamine group; N-biphenyl fluorenylamine group and the like, but is not limited thereto.

In the present specification, the description of the alkenyl group described above may be applied, except that the alkenylene group is a divalent group.

In the present specification, the description of the aryl group described above may be applied, except that the arylene group is a divalent group.

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

In one embodiment of the present specification, the conjugated monomer includes a combination of 1 or 2 or more of a substituted or unsubstituted alkenylene group, a substituted or unsubstituted arylene group, and a substituted or unsubstituted divalent heterocyclic group. do.

 In one embodiment of the present specification, the conjugated monomer includes any one or a combination of two or more of the following structures.

In the above structure,

X10 to X26 are the same as or different from each other, and each independently S, O, Se, Te, NR _d , CR _d R _e , SiR _d R _e , PR _d or GeR _d R _e ,

R110 to R133, R _d and R _e are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In the present specification, “combination” means connecting several structures or connecting different types of structures.

In one embodiment of the present specification, the conjugated monomer has any one of the following structures.

In the above structure,

X10 to X15 are the same as or different from each other, and each independently S, O, Se, Te, NR _d , CR _d R _e , SiR _d R _e , PR _d or GeR _d R _e ,

R110 to R115, R _d and R _e are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present specification, R112 to R115 are the same as or different from each other, and each independently a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present specification, the conjugated monomer has any one of the following structures.

In the above structure,

a, a ', b and b' are integers from 1 to 5,

c, c ', d and d' are integers from 1 to 3,

When a, a ', b, b', c, c ', d and d' are 2 or more, the substituents in parentheses are the same or different from each other,

X10 to X15 are the same as or different from each other, and each independently S, O, Se, Te, NR _d , CR _d R _e , SiR _d R _e , PR _d or GeR _d R _e ,

R110, R111, R200 to R207, R _d and R _e are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present specification, X10 to X15 are each S.

In one embodiment of the present specification, R110, R111, R200 to R207 are the same as or different from each other, and each independently hydrogen; Or a substituted or unsubstituted alkyl group.

In one embodiment of the present specification, R110, R111, R200 to R207 are the same as or different from each other, and each independently hydrogen; Or a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms.

In one embodiment of the present specification, R110, R111, R200 to R207 are the same as or different from each other, and each independently hydrogen; Or a substituted or unsubstituted alkyl group having 1 to 15 carbon atoms.

In one embodiment of the present specification, the conjugated monomer has any one of the following structures.

In one embodiment of the present specification, the copolymer has any one of the following structures.

In the above structure,

f is the molar fraction, and is a real number with 0 <f <1,

g is the molar fraction, and is a real number with 0 <g <1,

f + g = 1,

n is an integer from 1 to 10,000.

In one embodiment of the present specification, n is an integer from 2 to 5,000.

In one embodiment of the present specification, n is an integer from 5 to 1,000.

In one embodiment of the present specification, the terminal group of the copolymer is a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group.

In one embodiment of the present specification, the terminal group of the copolymer is a substituted or unsubstituted phenyl group; Or a substituted or unsubstituted thiophene group.

In one embodiment of the present specification, the number average molecular weight (Mn) of the copolymer is 5,000 g / mol to 1,000,000 g / mol. Preferably, the number average molecular weight of the copolymer is 8,000 g / mol to 100,000 g / mol. More preferably, the number average molecular weight of the copolymer is 10,000 g / mol to 100,000 g / mol.

An exemplary embodiment of the present specification is 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, wherein at least one layer of the organic material layer includes the copolymer.

1 is a view showing an organic electronic device 100 according to an exemplary embodiment of the present specification. Specifically, Figure 1 is a first electrode 20; A second electrode 60 provided to face the first electrode; And an organic material layer 70 provided between the first electrode and the second electrode.

In one embodiment of the present specification, the organic electronic device is selected from the group consisting of an organic photodiode, an organic transistor, an organic solar cell, and an organic light emitting device.

In one embodiment of the present specification, the organic electronic device may be an organic photodiode. Specifically, the organic electronic device 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, wherein at least one layer of the organic material layer includes the copolymer.

In one embodiment of the present specification, the organic electronic device may be an organic solar cell. Specifically, the organic electronic device 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, wherein at least one layer of the organic material layer includes the copolymer.

In one embodiment of the present specification, the organic material layer includes a photoactive layer.

Hereinafter, descriptions of the first electrode, the organic material layer including the photoactive layer, and the second electrode are commonly applied to the organic solar cell and the organic photodiode.

In one embodiment of the present specification, the photoactive layer includes the copolymer.

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

In one embodiment of the present specification, the electron acceptor includes fullerene, fullerene derivatives, vasocuproin, semiconducting compounds, non-fullerene derivatives, or combinations thereof.

In the present specification, “fullerene derivative” refers to a substance having one or more spherical shell structures in which molecules are formed of carbon. For example, fullerene as a spherical shell-like molecule; A fullerene derivative having an inorganic group or an organic group bound to the carbon-structured fullerene; Fullerene derivatives, such as a fullerene or a spherical shell structure constituting the fullerene derivative, are bonded directly or through one or more elements.

In one embodiment of the present specification, the fullerene derivative is PC ₆₀ BM (phenyl C ₆₀ -butyric acid methyl ester), PC ₆₁ BM (phenyl C ₆₁ -butyric acid methyl ester) or PC ₇₁ BM (phenyl C ₇₁ -butyric) acid methyl ester), ICBA (1 ′, 1 ′ ′, 4 ′, 4 ′ ′-Tetrahydro-di [1,4] methanonaphthaleno [1,2: 2 ′, 3 ′, 56,60: 2 ′ ′, 3 ′ ′] [5,6] fullerene-C ₆₀ ).

In one embodiment of the present specification, the non-fullerene derivative means a compound that does not contain fullerene. For example, the non-fullerene derivative is ITIC (3,9-bis (2-methylene- (3- (1,1-dicyanomethylene) -indanone))-5,5,11,11-tetrakis (4-hexylphenyl) -dithieno [2,3-d: 2 ', 3'-d']-s-indaceno [1,2-b: 5,6-b '] dithiophene).

In one embodiment of the present specification, the electron donor and the electron acceptor constitute a bulk heterojunction (BHJ).

The 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 and the electron acceptor may be mixed in a weight ratio of 1:10 to 10: 1. Specifically, the electron donor and the electron acceptor may be mixed in a weight ratio of 1: 1 to 1:10, and more specifically, the electron donor and electron acceptor may be mixed in a weight ratio of 1: 1 to 1: 5. If necessary, the electron donor and the electron acceptor may be mixed in a weight ratio of 1: 1 to 1: 3.

In one embodiment of the present specification, the photoactive layer is a bilayer structure including an n-type organic material layer and a p-type organic material layer, and the p-type organic material layer includes the copolymer.

In one embodiment of the present specification, the organic solar cell and the organic photodiode may further include an additional organic material layer. The organic solar cell and the organic photodiode may reduce the number of organic material layers by using organic materials having multiple functions simultaneously.

In one embodiment of the present specification, the organic solar cell and the organic photodiode are selected from the group consisting of a hole injection layer, a hole transport layer, a hole blocking layer, a charge generating layer, an electron blocking layer, an electron injection layer and an electron transport layer 1 Or further comprising two or more organic material layers.

In one embodiment of the present specification, the organic material layer includes a hole transport layer, a hole injection layer, or a layer that simultaneously performs hole transport and hole injection, and the hole transport layer, hole injection layer, or a layer that simultaneously performs hole transport and hole injection It includes the said copolymer.

In another exemplary embodiment, the organic material layer includes an electron injection layer, an electron transport layer, or a layer that simultaneously performs electron injection and electron transport, and the electron injection layer, electron transport layer, or layer that simultaneously performs electron injection and electron transport is It includes the said copolymer.

In one embodiment of the present specification, the organic solar cell and the organic photodiode include a first electrode, a photoactive layer and a second electrode. The organic solar cell and the organic photodiode may further include a substrate, a hole transport layer and / or an electron transport layer.

In one embodiment of the present specification, the organic solar cell and the organic photodiode further include a substrate, an electron transport layer and a hole transport layer.

2 is a substrate 10, a first electrode 20, an electron transport layer 30, a photoactive layer 40, a hole transport layer 50 and a second electrode 60 according to one embodiment of the present specification It is a diagram showing an organic solar cell.

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

In one embodiment of the present specification, the organic solar cell and the organic photodiode have 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 and the organic photodiode have 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.

In 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 limited to substrates commonly used in organic solar cells and / or organic photodiodes. Does not work. Specifically, there are glass or PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PI (polyimide), TAC (triacetyl cellulose). It is not limited to this.

The first electrode may be a material that is transparent and has excellent conductivity, 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), and indium zinc oxide (IZO); A combination of metal and oxide such as ZnO: Al or SnO ₂ : Sb; Conductive polymers such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDOT), polypyrrole, and polyaniline, but are not limited thereto.

The method for forming the first electrode is not particularly limited, but is applied to one surface of the substrate or in the form of a film using, for example, sputtering, E-beam, thermal vapor deposition, spin coating, screen printing, inkjet printing, doctor blade or gravure printing. It can be formed by coating.

When the first electrode is formed on the substrate, it may undergo cleaning, water removal, and hydrophilic modification processes.

For example, the patterned ITO substrate is sequentially washed with a cleaning agent, acetone, and isopropyl alcohol (IPA), and then heated at 100 ° C. to 150 ° C. for 1 minute to 30 minutes, preferably 120 ° C. for 10 minutes to remove moisture. When it is dried and the substrate is completely cleaned, the substrate surface is modified to be hydrophilic.

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

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

One of the above methods can be selected according to the state of the first electrode or the substrate. However, in any method, it is desirable to prevent oxygen desorption on the surface of the first electrode or the substrate in common and to suppress the residual of moisture and organic matter as much as possible. At this time, the practical effect of the pretreatment can be maximized.

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

However, the method of surface modification of the patterned ITO substrate in the present specification is not particularly limited, and any method may be used as long as it is a method of oxidizing the substrate.

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

The second electrode is 5x10 ^- may be formed is deposited on the internal heat evaporator showing a degree of vacuum of less than ⁷ torr, not limited to this method.

The hole transport layer and / or electron transport layer material plays a role of efficiently transferring electrons and holes separated from the photoactive layer to the electrode, and does not specifically limit the material.

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

The electron transport layer may include electron-extracting metal oxides as an electron transport material, and specifically, a 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 ), but is not limited thereto.

In one embodiment of the present specification, the photoactive layer dissolves a photoactive material, such as an electron donor and / or an electron acceptor, in an organic solvent, followed by spin coating, dip coating, screen printing, spray coating, doctor blade, brush painting, etc. It can be formed by the method, but is not limited to these methods.

The manufacturing method of the copolymer and the production of an organic solar cell including the same will be described in detail in the following Production Examples and Examples. However, the following examples are intended to illustrate the present specification, and the scope of the present specification is not limited by them.

Preparation Example 1.

(1) Preparation of compound a-2

Compound a-1 (5.0 g, 9 mmol) was dissolved in 250 mL of THF and 1 M lithium diisopropylamide (LDA) (15 mL, 15 mmol) was slowly injected at -78 ° C. After the reaction for 1 hour, trimethyltin chloride (trimethyltin chloride, Me ₃ SnCl) (1M, 15mmol) was slowly injected and the temperature was raised to room temperature and stirred at room temperature for 5 hours. After washing with an aqueous sodium chloride (NaCl) solution, the solvent was evaporated under vacuum to obtain 5.84 g of compound a-2. (Yield: 90%)

3 is a diagram showing the results of MS measurement of compound a-2.

4 is a diagram showing the results of NMR measurement of compound a-2.

(2) Preparation of compound a-4

Dissolve compound a-2 (2.89 g, 4 mmol) and compound a-3 (2.41 g, 4 mmol) in 50 mL toluenen, tetrakis (triphenylphosphine) palladium (0) catalyst (Pd (PPh ₃ ) ₄ ) (0.058g, 0.05mmol), and gradually heated to react at 110 ° C for 48 hours. Upon cooling, the resulting residue was precipitated in methanol, filtered and washed with water. After that, the solvent is evaporated through a drying process, and the residual product is purified through flash chromatography using methylene chloride and chloroform, and then recrystallized using methylene chloride and methanol. To give a solid. The solid was washed with methanol and dried under vacuum for 24 hours to obtain 2.1 g of Compound a-4. (Yield 49%)

5 is a diagram showing the results of MS measurement of compound a-4.

6 is a diagram showing the results of NMR measurement of compound a-4.

(3) Preparation of compound a-5

Compound a-4 (0.67 g, 0.62 mmol) and N-bromosuccinimide (NBS) (0.142 g, 0.8 mmol) were added to 40 mL of THF at 0 ° C. and stirred at room temperature for 24 hours. Then, the solvent was evaporated, and the residue was purified through flash chromatography (eluent (hexane to hexane: methylene chloride)) to obtain 0.46 g of compound a-5. (Yield: 68%)

7 is a diagram showing the results of MS measurement of compound a-5.

(4) Preparation of copolymer 1-1 and copolymer 1-2

In a nitrogen (N ₂ ) atmosphere, 9 mL of toluene, 3 mL of dimethylformamide (DMF), compound a-5 (0.41 mmol), and compound b-1 (0.41 mmol) were added to a 100 mL flask, followed by nitrogen bubbling for 30 minutes. Thereafter, tetrakis (triphenylphosphine) palladium (0) catalyst (Pd (PPh ₃ ) ₄ ) (2 mol%) was added thereto, followed by stirring at 110 ° C. for 72 hours. After adding 0.5 mL of Br-benzotrifluoride (Br-Benzotrifluoride), the mixture was stirred for 24 hours and cooled to room temperature. The product was then poured into chloroform, passed through a short column with silica, and poured into a mixed solution (180 mL methanol + 20 mL HCl (2M concentration)) to filter the precipitate. Thereafter, the product was subjected to soxhlet extraction in the order of methanol, acetone, hexane, methylene chloride and chloroform. The extract extracted with chloroform was put in methanol to form a precipitate. The resulting precipitate was collected and purified, and dried under vacuum to prepare copolymers 1-1 and 1-2. At this time, by measuring the number average molecular weight (Mn), it was confirmed that the copolymer 1-1 or 1-2 was prepared. (Yield: 94%, Mn = 31,400 g / mol, PDI = 2.2)

When preparing the copolymer 1-2 as in Preparation Example 1, steric hindrance may exist between the compound a-5 and the compound b-1 in which a bulky alkyl chain is introduced on one side. Accordingly, the non-bulky portion of compound a-5 and compound b-1 may react first. Accordingly, the following compound J may be first generated before copolymer 1-2 is produced.

However, in the method of preparing the copolymer 1-2, since the same amount of the compound a-5 and the compound b-1 are added, the remaining b-1 after formation of the structure as described above is additionally bound to the copolymer 1-2. To be manufactured.

However, since the compound J is not first generated in all reactions, finally, the copolymer 1-1 (asymmetric alternating copolymer) and the copolymer 1-2 (block copolymer) are prepared by mixing.

8 is a DSC measurement result of copolymer 1-2.

8, it can be confirmed that it has a melting point near 280 ° C and crystallization near 270 ° C. Through this, it was confirmed that the copolymer 1-2 (block form) was formed more (dominantly) to have excellent crystallinity.

Preparation Example 2.

In Preparation Example 1, copolymers 2-1 and 2-2 were prepared in the same manner as in Production Example 1, except that Compound b-2 was used instead of Compound b-1. At this time, the number average molecular weight (Mn) was measured to confirm that copolymers 2-1 and 2-2 were prepared. (Yield: 67%, Mn = 32,500 g / mol, PDI = 2.7)

Preparation Example 3.

In Preparation Example 1, copolymers 3-1 and 3-2 were prepared in the same manner as in Preparation Example 1, except that Compound b-3 was used instead of Compound b-1. At this time, the number average molecular weight (Mn) was measured to confirm that copolymers 3-1 and 3-2 were prepared. (Yield: 72%, Mn = 35,100 g / mol, PDI = 2.4)

Comparative Production Example 1.

In a nitrogen (N2) atmosphere, put 8 mL of toluene, 2 mL of DMF, compound c-1 (0.07 mmol), compound c-2 (0.07 mmol) and compound b-1 (0.14 mmol) in a 100 mL flask and nitrogen bubbling for 30 minutes. Did. Thereafter, tetrakis (triphenylphosphine) palladium (0) catalyst (Pd (PPh ₃ ) ₄ ) (2 mol%) was added thereto, followed by stirring at 110 ° C. for 72 hours. After adding 0.5 mL of Br-benzotrifluoride (Br-Benzotrifluoride), the mixture was stirred for 24 hours and cooled to room temperature. The product was then poured into chloroform, passed through a short column with silica, and poured into a mixed solution (180 mL methanol + 20 mL HCl (2M concentration)) to filter the precipitate. Thereafter, the product was subjected to soxhlet extraction in the order of methanol, acetone, hexane, methylene chloride and chloroform. The extract extracted with chloroform was put in methanol to form a precipitate. The resulting precipitate was collected and purified, and dried under vacuum to obtain copolymer K. At this time, by measuring the number average molecular weight (Mn), it was confirmed that the copolymer K was prepared. (Mn = 21,200g / mol, PDI = 2.6)

Example 1. Preparation of organic solar cell

Copolymers 1-1 and 1-2 prepared in Preparation Example 1 were used as donors, and dissolved in chlorobenzene (CB) at a ratio of 1: 1.5 using ITIC as an acceptor to prepare a composite solution. It was prepared. At this time, the concentration was adjusted to 2.0 wt%, and the organic solar cell had a structure of ITO / ZnO / photoactive layer / MoO ₃ / Ag. The ITO-coated glass substrate was ultrasonically cleaned using distilled water, acetone, and 2-propanol, ozonized the ITO surface for 10 minutes, and then spin-coated the ZnO precursor solution for 10 minutes at 120 ° C. Thereafter, the composite solution was filtered through a 0.45 μm PTFE syringe filter, and then spin-coated to form a photoactive layer. Thereafter, MoO ₃ was deposited on the photoactive layer to a thickness of 5 nm to 20 nm at a rate of 0.4 Pa / s in a thermal evaporator to prepare a hole transport layer. Thereafter, Ag was deposited at 10 nm on the hole transport layer at a rate of 1 kPa / s inside the thermal evaporator to prepare an organic solar cell.

Example 2.

An organic solar cell was manufactured in the same manner as in Example 1, except that Copolymers 2-1 and 2-2 were used instead of Copolymers 1-1 and 1-2 in Example 1.

Example 3.

An organic solar cell was prepared in the same manner as in Example 1, except that Copolymers 3-1 and 3-2 were used instead of Copolymers 1-1 and 1-2 in Example 1.

Comparative Example 1.

An organic solar cell was manufactured in the same manner as in Example 1, except that in Example 1, copolymer K was used instead of copolymers 1-1 and 1-2.

The photoelectric conversion characteristics of the prepared organic solar cells prepared in Examples 1 to 3 and Comparative Example 1 were measured under 100 mW / cm ² (AM 1.5) conditions, and the results are shown in Table 1.

V _oc
(V) J _sc
(mA / cm ² ) FF η
(%) Example 1 0.87 15.27 0.62 8.23 Example 2 0.83 16.19 0.59 7.93 Example 3 0.82 16.75 0.60 8.24 Comparative Example 1 0.78 10.50 0.51 4.18

In Table 1, Voc is the open voltage, Jsc is the short-circuit current density, FF is the fill factor, and PCE is the energy conversion efficiency. The open-voltage and short-circuit current densities are the X-axis and Y-axis intercepts in the quadrant of the voltage-current density curve, respectively, and the higher these two values, the higher the efficiency of the solar cell is. In addition, the fill factor is a value obtained by dividing the maximum area of the rectangle that can be drawn inside the curve by the product of the short-circuit current density and the open voltage. The energy conversion efficiency can be obtained by dividing these three values by the intensity of the irradiated light, and the higher the value, the better.

From Table 1, it can be confirmed that Examples 1 to 3 are superior in performance to Comparative Example 1.

10: substrate
20: first electrode
30: electron transport layer
40: photoactive layer
50: hole transport layer
60: second electrode
70: organic layer
100: organic electronic device

Claims (13)

A unit represented by Formula 1 below; And
Copolymers comprising conjugated monomers:
[Formula 1]

In Chemical Formula 1,
X1 to X3 are the same as or different from each other, and each independently CRR ', NR, O, SiRR', PR, S, GeRR ', Se or Te,
R1 to R8, R and R 'are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group. The method according to claim 1,
The copolymer represented by the formula (1) and the conjugated monomer are alternately provided in the copolymer. The method according to claim 1,
The conjugated monomer is a copolymer comprising a combination of 1 or 2 or more of a substituted or unsubstituted alkenylene group, a substituted or unsubstituted arylene group, and a substituted or unsubstituted divalent heterocyclic group. The method according to claim 1,
The conjugated monomer is a copolymer comprising any one or a combination of two or more of the following structures:

In the above structure,
X10 to X26 are the same as or different from each other, and each independently S, O, Se, Te, NR _d , CR _d R _e , SiR _d R _e , PR _d or GeR _d R _e ,
R110 to R133, R _d and R _e are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group. The method according to claim 1,
The copolymer is a copolymer comprising a structure represented by the following formula (2):
[Formula 2]

In Chemical Formula 2,
f is the molar fraction, and is a real number with 0 <f <1,
g is the molar fraction, and is a real number with 0 <g <1,
f + g = 1,
n is an integer from 1 to 10,000,
E is a conjugated monomer,
X1 to X3 are the same as or different from each other, and each independently CRR ', NR, O, SiRR', PR, S, GeRR ', Se or Te,
R1 to R8, R and R 'are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group. The method according to claim 1,
The copolymer is a copolymer comprising a structure represented by the following formula (3):
[Formula 3]

In Chemical Formula 3,
n is an integer from 1 to 10,000,
E is a conjugated monomer,
X1 to X3 are the same as or different from each other, and each independently CRR ', NR, O, SiRR', PR, S, GeRR ', Se or Te,
R1 to R8, R and R 'are the same as or different from each other, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group. The method according to claim 1,
The copolymer is a copolymer comprising any one of the following structures:

In the above structure,
f is the molar fraction, and is a real number with 0 <f <1,
g is the molar fraction, and is a real number with 0 <g <1,
f + g = 1,
n is an integer from 1 to 10,000. A first electrode;
A second electrode provided to face the first electrode; And
An organic electronic device including at least one organic layer provided between the first electrode and the second electrode,
At least one layer of the organic layer is an organic electronic device comprising the copolymer according to any one of claims 1 to 7. The method according to claim 8,
The organic electronic device is an organic electronic device selected from the group consisting of an organic photodiode, an organic transistor, an organic solar cell, and an organic light emitting device. The method according to claim 8,
The organic electronic device includes a first electrode;
A second electrode provided to face the first electrode; And
An organic photodiode comprising at least one layer of an organic material provided between the first electrode and the second electrode,
At least one layer of the organic material layer is an organic electronic device comprising the copolymer. The method according to claim 10,
The organic layer includes a photoactive layer,
The photoactive layer includes an electron donor and an electron acceptor,
The electron donor is an organic electronic device comprising the copolymer. The method according to claim 8,
The organic electronic device includes a first electrode;
A second electrode provided to face the first electrode; And
An organic solar cell including at least one organic layer provided between the first electrode and the second electrode,
At least one layer of the organic material layer is an organic electronic device comprising the copolymer. The method according to claim 12,
The organic layer includes a photoactive layer,
The photoactive layer includes an electron donor and an electron acceptor,
The electron donor is an organic electronic device comprising the copolymer.

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