KR20180082110A - Preparation of phenazine derivatives with increased solubility and conjugated polymers consisting of phenazine derivatives for organo photoelectric conversion device - Google Patents

Abstract

The present invention relates to a new hole transport polymer and/or monomer, a method of producing the same, and an organic photoelectric conversion element employing the new hole transport polymer as an active layer. The hole transport polymer comprises a polymerization unit represented by chemical formula 1. The present invention provides a series of production processes of hole transport polymer and/or monomer with a superior photoelectric conversion efficiency having improved light absorbing properties up to a long wavelength when a heterocyclic compound is introduced and also having moving characteristics of electric charges through effective electron transfer by an effective tasking between molecules, and provides an organic photoelectric conversion element employing the hole transfer polymer as a photoactive layer, thereby obtaining effects of exhibiting stable photoelectric conversion efficiency such that the present invention is able to be usefully used as a next generation organic photoelectric conversion element with the excellent conversion efficiency.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a phenazine derivative having increased solubility and a polymer for organic photoelectric conversion device using the same. BACKGROUND ART [0002] Conventional photovoltaic devices,

The present invention relates to a hole transporting polymer and an organic photoelectric conversion device including the same.

Recently, as oil prices and environmental pollution problems have arisen, demand for low-cost eco-friendly energy sources is rapidly increasing. Solar energy, such as solar power, wind power, hydro power, wave power, and geothermal power, are examples of eco-friendly energy sources. Solar power generation that can generate electricity using solar power is an unlimited energy source without risk of environmental pollution. For example, the actual amount of solar energy available on the planet is 600TW (1TW = 1 × 1,012 Watts), which is a tremendous amount that is estimated at 60 times the energy used today. For this reason, research on photoelectric devices using solar light has been conducted for several decades, and inorganic solar cells using silicon wafers are now commercially available.

However, inorganic solar cells are not suitable for flexible solar cells or wearable solar cells combined with energy sources for low-cost electronic products or flexible displays, because they are used for large-scale generation for a long period of time due to high raw material costs. Therefore, researches on solar cells using organic semiconductors are being actively carried out.

Photovoltaic (PV) is a phenomenon in which photons are separated into electrons and holes in an organic active layer that receives sunlight to form an exciton, which is an electron donor and an acceptor material Means that it moves to the interface and is separated by the difference of each LUMO level to produce electricity.

The photoelectric conversion phenomenon in the organic material is formed by the structure of ITO / CuPc (30 nm) / PV (50 nm) / Ag in Eastman Kodak Co. in 1987 by Tang et al. Photoelectric conversion efficiency of 0.95% was first reported under AM2.0 conditions. Since then, the development of photoelectric conversion efficiency of 1% or less has made considerable progress due to the introduction of fullerene and the development of derivative thereof, PCBM.

In general, for high efficiency photoelectric conversion efficiency, photon harvesting characteristics capable of absorbing a wide range of sunlight must be preceded, and effective stacking between molecules is required for effective electron and hole transport. For this purpose, a molecular structure capable of providing effective molecular stacking to the main chain of the polymer is introduced to increase the charge mobility by inducing stacking between the polymers.

Therefore, a novel photoelectric conversion polymer using a phenazine derivative having properties of good solubility, oxidation stability and charge mobility as an active layer of an organic photoelectric conversion element of a push-pull structure, and organic photoelectric conversion Development of a device is required.

Korean Patent Publication No. 2013-0038548.

Reference 1: J. Am. Chem. Soc. 2014, 136, 427-435, J. Am. Chem. Soc. 2004, 126, 6035-6042.

It is an object of the present invention to provide a hole transporting polymer having excellent photoelectric conversion efficiency which is excellent in solubility and oxidation stability and has high solubility and has high charge mobility due to π-π stacking between molecules, And to provide an organic photoelectric conversion device employed as a transport layer.

In order to solve the above problems, the present invention provides a hole-transporting polymer comprising a polymerization unit represented by the following formula (1).

[Chemical Formula 1]

In Formula 1,

M is a p-type molecule,

A is independently a single bond, alkylene having 1 to 20 carbon atoms, alkenylene having 2 to 20 carbon atoms, alkynylene having 2 to 20 carbon atoms, aralkylene having 7 to 15 carbon atoms, cycloalkylene having 3 to 20 carbon atoms , Alkynylene having 6 to 20 carbon atoms, arylene having 6 to 30 carbon atoms, ararylene having 7 to 20 carbon atoms, or heteroarylene having 4 to 20 carbon atoms,

R _a is independently hydrogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,

R _b is independently hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,

and n is an integer of 1 to 1,000,000.

Also, the present invention provides an organic photoelectric conversion device in which a first electrode, a layer including the hole transporting polymer, a photoelectric conversion layer, and a second electrode are laminated.

The present invention provides a hole transporting polymer having excellent photoelectric conversion efficiency, which is excellent in solubility and oxidation stability and has high charge mobility due to stacking between molecules, so that the above polymer is employed as a hole transporting layer and organic photoelectric conversion And the organic photoelectric conversion device can be easily manufactured by a relatively simple process such as spin coating. By selecting a suitable electron donor or electron accepting material and using the intermolecular interaction, the HOMO level and the LUMO level can be stabilized It can be utilized as a next generation organic photoelectric conversion device having high photoelectric conversion efficiency and excellent photoelectric conversion efficiency.

1 is a cross-sectional view of an organic photoelectric conversion device according to Examples 3 and 4 of the present invention.
2 and 3 are the light absorption spectra of Examples 1 and 2, respectively.
4 is a cyclic voltammetry (CV) graph for evaluating the electrochemical characteristics of Example 3. FIG.
5 is a graph showing the efficiency of the organic photoelectric conversion device according to the third embodiment.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various elements, but the elements should not be limited by terms. Terms are used only for the purpose of distinguishing one component from another.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Therefore, the configurations shown in the embodiments described herein are merely the most preferred embodiments of the present invention and are not intended to represent all of the technical ideas of the present invention. Therefore, various equivalents And variations.

The present invention provides a series of processes for producing a hole transporting polymer and / or a single molecule having excellent photoelectric conversion efficiency, which is excellent in solubility and oxidation stability and has high charge mobility due to stacking between molecules, And an organic photoelectric conversion element employed as a photoactive layer.

Hereinafter, the hole transporting polymer according to the present invention will be described in detail.

The hole transporting polymer according to the present invention comprises a polymerized unit represented by the following formula (1).

[Chemical Formula 1]

In Formula 1,

M is a p-type molecule,

A is independently a single bond, alkylene having 1 to 20 carbon atoms, alkenylene having 2 to 20 carbon atoms, alkynylene having 2 to 20 carbon atoms, aralkylene having 7 to 15 carbon atoms, cycloalkylene having 3 to 20 carbon atoms , Alkynylene having 6 to 20 carbon atoms, arylene having 6 to 30 carbon atoms, ararylene having 7 to 20 carbon atoms, or heteroarylene having 4 to 20 carbon atoms,

R _a is independently hydrogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,

R _b is independently hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,

and n is an integer of 1 to 1,000,000.

In the present invention, the polymerization unit represented by the formula (1) may include at least one polymerized unit selected from the group consisting of the following units represented by the following formulas (1-a) and (1-b)

[Chemical Formula 1-a]

[Chemical Formula 1-b]

Wherein M, A, R _a , R _b and n are as defined in the above formula (1).

The p-type molecule according to the present invention is not particularly limited as long as it has an electron-donating property. For example, a molecule selected from molecules represented by the following formulas 2-a to 2-c And may include one or more species.

[Chemical Formula 2-a]

[Formula 2-b]

[Chemical Formula 2-c]

In the above formulas 2-a to 2-c,

X ₁ to X ₄ independently of one another are O, S or Se,

Y ₁ and Y ₂ are independently of each other N or CR _d ,

R _c to R _e independently represent hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group and the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,

m and p are each independently an integer of 1 to 10;

Specifically, in Formula 2-a,

X ₁ is O, S or Se, R _c is independently of each other hydrogen or an alkyl group having 1 to 4 carbon atoms, and m may be 1 to 4.

More specifically, in Formula 2-a, X ₁ is S, R _c is independently hydrogen or an alkyl group having 1 to 4 carbon atoms, and m may be 1.

In the above formula (2-b)

X ₂ and X ₃ are independently of each other O, S or Se, Y ₁ and Y ₂ independently of one another are N or CR _d , R _d is hydrogen or an alkyl group having 1 to 25 carbon atoms, and p can be 1 .

Further, in the above formula (2-c)

X < ₄ > is O, S or Se,

R _e is independently hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group and the heteroaryl group may be substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms.

As one example, a molecule having an electron-donating property (p-type molecular) according to the present invention may include at least one selected from compounds represented by the following formula (2-d).

[Chemical Formula 2-d]

In Formula 2-d,

R ₁ to R ₁₂₀ independently from each other are hydrogen; halogen; An alkyl group having 1 to 25 carbon atoms; An alkoxy group having 1 to 25 carbon atoms; An aryl group having 5 to 30 carbon atoms; Thiophene group; A cellonopene group; A roll roll; Or a thiazole group,

At least one of the hydrogen atoms present in the aryl group, thiophene group, cyclophenylene group, pyrrole group and thiazole group is an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 1 to 30 carbon atoms Substituted or unsubstituted.

In addition, A according to the present invention may be a single bond or at least one compound selected from compounds represented by the following general formula (9).

[Chemical Formula 9]

Wherein R < ₁₂₁ > is independently from each other hydrogen; halogen; An alkyl group having 1 to 25 carbon atoms; An alkoxy group having 1 to 25 carbon atoms; An aryl group having 5 to 30 carbon atoms; Thiophene group; A cellonopene group; A roll roll; Or a thiazole group,

At least one of the hydrogen atoms present in the aryl group, thiophene group, cyclophenylene group, pyrrole group and thiazole group is an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 1 to 30 carbon atoms Substituted or unsubstituted.

The polymerization unit represented by the formula (1) according to the present invention may include at least one polymerization unit selected from the group consisting of the polymerization units represented by the following formulas (3) to (6).

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas 3 to 6,

A is a single bond or alkylene having 1 to 6 carbon atoms,

X ₅ and X ₆ are independently of each other O or S,

R _a and R _b independently represent hydrogen, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group or nonyloxy group,

R _c and R _e independently represent hydrogen, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a phenyl group, a naphthyl group, a pyrrolyl group or a thiazole group,

At least one of the hydrogen atoms present in the phenyl group, the naphthyl group, the pyrrolyl group and the thiazole group is substituted or unsubstituted with a pentyl group, a hexyl group, a heptyl group, an octyl group or a nonyl group,

and q is an integer of 1 to 1,000.

As one example, the polymerization unit represented by the formula (1) in the present invention may include at least one polymerization unit selected from the group consisting of the following units represented by the following formulas (7) and (8).

(7)

[Chemical Formula 8]

In the general formulas (7) and (8), r is an integer of 1 to 1,000.

The solubility of the hole transporting polymer according to the present invention is remarkably increased by including the phenazine derivative in the polymerization unit represented by the formula (1), and the organic photoelectric conversion device including the hole transporting polymer exhibits effective stacking between molecules according to excellent planarity It is possible to provide an organic photoelectric conversion element having excellent charge and electron mobility.

Further, the present invention provides a process for producing a hole transporting polymer.

The method for producing a hole transporting polymer according to the present invention is not particularly limited as long as it is a method for producing a polymer compound in the field to which this technology belongs, but may specifically include the processes of the following Schemes 1 and 2.

[Reaction Scheme 1]

[Reaction Scheme 2]

For example, the hole transporting polymer according to the present invention can be produced using stille coupling. At this time, xylene, toluene, dimethylformamide (DMF) and the like can be used as the solvent, and 0.5 to 10 mol% of tetrakis (triphenylphosphine) palladium is used A polymer can be obtained.

Specifically, 1.5 mol% of tetrakis (triphenylphosphine) palladium (tetrakistriphenylphosphinepalladium) was added to the toluene (Toluene) for 48 hours after the addition of the phenazine precursor (B) and the M precursor 90 < 0 > C). Then, 0.1 ml of bromothiophene can be dropped and the reaction can be carried out for 12 hours. After the TLC has been confirmed, the reaction can be quenched with HCl. Then, it is extracted with chloroform and washed with distilled water, and then the water is removed and the column purified to obtain the hole transporting polymer (C) of the above reaction formula (1).

In the Reaction Scheme 1 of the present invention, the precursor (B) for producing the hole transporting polymer may include at least one selected from the compounds represented by the following Chemical Formula (10).

[Chemical formula 10]

In Formula 10,

R _f is independently from each other hydrogen; An alkyl group having 1 to 25 carbon atoms; An alkoxy group having 1 to 25 carbon atoms; An aryl group having 5 to 30 carbon atoms; A phenyl group; Or a pyrrolyl group,

At least one of the hydrogen atoms present in the aryl group, the phenyl group and the pyrrole group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 1 to 30 carbon atoms.

As an example, in Scheme 1, the phenazine precursor (B) is 10-13-dibromo-3,6-bis (octyloxy) dibenzo [a, c] , 6-bis (octyloxy) dibenzo [a, c] phenazine) may be used.

The M precursor (A) is not particularly limited as long as it forms a molecule exhibiting electron-donating properties in a polymerization unit. As an example, the M precursor (A) may be an indacenodithieno- thiophene) can be used.

1.5 mol% of phenazine precursor (B) and M precursor (A) and tetrakis (triphenylphosphinepalladium) palladium were added to toluene and stirred for 48 hours (90 ° C) . Then, 0.1 ml of bromothiophene can be dropped and the reaction can be carried out for 12 hours. After the TLC has been confirmed, the reaction can be quenched with HCl. Then, it is extracted with chloroform and washed with distilled water, and water is removed therefrom. Column purification can be performed to obtain the hole transporting polymer (C) of the reaction formula (2).

In the reaction formula 2 of the present invention, as starting materials for preparing the hole transporting polymer, at least one selected from compounds represented by the following general formula (11) may be included.

(11)

In Formula 11,

R _g independently from each other are hydrogen; An alkyl group having 1 to 25 carbon atoms; An alkoxy group having 1 to 25 carbon atoms; An aryl group having 5 to 30 carbon atoms; A phenyl group; Or a pyrrolyl group,

At least one of the hydrogen atoms present in the aryl group, the phenyl group and the pyrrole group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 1 to 30 carbon atoms.

As an example, in Scheme 2, the phenazine precursor (B) is 10-13-dibromo-2,7-bis (octyloxy) dibenzo [a, c] , 7-bis (octyloxy) dibenzo [a, c] phenazine) can be used.

The M precursor (A) is not particularly limited as long as it forms a molecule exhibiting electron-donating properties in a polymerization unit. As an example, the M precursor (A) may be 2,5-bis (trimethylstannyl) 2,5-bis (trimethylstannyl) thiophene may be used.

Hereinafter, the organic photoelectric conversion device according to the present invention will be described in detail.

An organic photoelectric conversion device according to the present invention includes: a first electrode; A layer comprising a hole transporting polymer according to the present invention; A photoelectric conversion layer; And a second electrode are stacked. Further, an organic photoelectric conversion device according to the present invention includes: a first electrode; A hole transport layer including the hole transport polymer according to the present invention; A photoelectric conversion layer; And the second electrode may be laminated.

The structure of the organic photoelectric conversion device of the present invention may further include a hole transport layer and / or an electron transport layer as well as the most general device structure including an anode, a photoelectric conversion layer and a cathode. Herein, the anode may mean the first electrode of the present invention, and the cathode may mean the second electrode of the present invention. The organic photoelectric conversion device of the present invention may be manufactured in the order of an anode, a hole transporting layer, a photoelectric conversion layer, an electron transporting layer, and a cathode, and may be manufactured in the reverse order: a cathode, an electron transporting layer, a photoelectric conversion layer, a hole transporting layer, May be manufactured in that order. At this time, the photoelectric conversion layer may be formed by spin coating, and its thickness may be in the range of 10 to 10,000 angstroms. The hole transport layer may be formed on the anode electrode by vacuum evaporation or spin coating, and the electron transport layer may be formed on the photoelectric conversion layer before forming the cathode. The electron transport layer may be a conventional material for forming an electron transport layer, and the thickness of the hole transport layer and the electron transport layer may be in the range of 1 to 10,000 angstroms.

In the present invention, the first electrode may be an anode electrode, and the first electrode may further include a transparent substrate. The transparent substrate may be any substrate as long as it is used in a conventional organic photoelectric conversion device and is excellent in transparency, surface smoothness, ease of handling, and waterproofness. Examples of the transparent substrate include transparent glass, Substrates include polyethylene terephthalate (PET), polyethylene naphthelate (PEN), polypropylene (PP), polyimide (PI), and triacetyl cellulose (TAC) A transparent glass substrate can be used. More specifically, a transparent glass substrate can be used. In addition, the anode electrode according to the present invention may be formed by coating an anode electrode material on the transparent substrate. The anode electrode material may include transparent indium tin oxide (ITO), transparent conductive oxide annotations may include a (SnO2), zinc oxide _{(ZnO), SnO 2 -Sb 2} O 3 and the like.

In the present invention, the hole transporting layer and the electron transporting layer may have a function of controlling the interface energy between the first electrode and the photoelectric conversion layer to smoothly induce the charge flow and improve the mobility. The hole transporting layer and the electron transporting layer material are not particularly limited, but specific examples of the hole transporting layer material include poly (3,4-ethylenedioxy-thiophene) doped with poly (styrenesulfonic acid) Bis (3-methylphenyl) -N, N-diphenyl- [1,1'-biphenyl] -4,4'- diamine (TPD) can be used, and as the electron transport layer material, aluminum trihydroxyquinoline trihydroxyquinoline; Alq ₃ ), 1,3,4-oxadiazole derivative PBD (2- (4-biphenylyl) -5-phenyl-1,3,4-oxadiazole, quinoxaline derivative TPQ -tris [(3-phenyl-6-trifluoromethyl) quinoxaline-2-yl] benzene) and triazole derivatives can be used. The electron transport layer and the hole transport layer efficiently transport electrons and holes to the photoelectric conversion polymer It is possible to increase the probability of movement of charges generated by applying the voltage to the electrodes.

The photoelectric conversion layer according to the present invention may be a bulk heterojunction structure or a double layer junction structure as an active layer which substantially performs the function of generating electrical energy. The bulk heterojunction structure may be a bulk heterojunction (BHJ) junction type and the bilayer junction structure may be a bi-layer junction type. The BJJ (bulk jitter junction) photoactive unit may include a photoactive layer in which an n-type semiconductor and a p-type semiconductor are blended. In addition, the bi-layer p-n junction type photoactive unit may include a photoactive layer composed of two layers of a p-type semiconductor thin film and an n-type semiconductor thin film. Specifically, in the photoelectric conversion layer, the p-type semiconductor forms excitons paired with electrons and holes by photoexcitation, and the excitons are separated into electrons and holes at the p-n junction. The separated electrons and holes migrate to the n-type semiconductor thin film and the p-type semiconductor thin film, respectively, and they are collected in the first electrode and the second electrode, respectively, so that they can be used as electric energy from the outside. At this time, the photoelectric conversion layer may include an electron donating material which is a p-organic semiconductor compound and an electron accepting material which is an n-organic semiconductor material as a photoactive material. In the photoelectric conversion layer, the electron donor material forms an exciton paired with electrons and holes by photoexcitation, and the exciton is separated into electrons and holes at the interface of the electron donor / electron acceptor. The separated electrons and holes are respectively transferred to the electron donating material and the electron accepting material, and they are collected in the first electrode and the second electrode, respectively, so that they can be used as electric energy from the outside.

As such a photoactive material, the present invention can include a hole transporting polymer represented by the following Formula 1:

[Chemical Formula 1]

In Formula 1,

M is a p-type molecule,

A is independently a single bond, alkylene having 1 to 20 carbon atoms, alkenylene having 2 to 20 carbon atoms, alkynylene having 2 to 20 carbon atoms, aralkylene having 7 to 15 carbon atoms, cycloalkylene having 3 to 20 carbon atoms , Alkynylene having 6 to 20 carbon atoms, arylene having 6 to 30 carbon atoms, ararylene having 7 to 20 carbon atoms, or heteroarylene having 4 to 20 carbon atoms,

R _a is independently hydrogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,

R _b is independently hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,

At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,

and n is an integer of 1 to 1,000,000.

In addition, the photoelectric conversion layer according to the present invention can be produced by mixing a hole transporting polymer synthesized with the structure of Formula 1 and a PC ₆₁ BM (phenyl C61-butyric acid methyl ester) or a PC ₇₁ BM (phenyl C71-butyric acid methyl ester) And may be formed in a bulk heterojunction type with various fullerene derivatives. At this time, the hole transporting polymer and PCBM can be mixed in a ratio (w / w) ranging from 1:10 to 10: 1. In order to maximize the photoelectric conversion efficiency of the photoelectric conversion layer, Lt; / RTI > to 24 hours.

In the present invention, the second electrode may be a cathode electrode or an electrode containing a metal. At this time, the cathode electrode may be made of a metal having a small work function. Examples of the cathode electrode include gold (Au), silver (Ag), lithium (Li), magnesium (Mg) Or an aluminum / lithium alloy (Al: Li), an aluminum / barium fluoride alloy (Al: BaF ₂ ), an aluminum / barium fluoride / barium alloy (Al: BaF ₂ : Ba) ), A magnesium / silver alloy (Mg: Ag), and an aluminum / lithium fluoride alloy (Al: LiF).

Hereinafter, the present invention will be described in more detail with reference to examples and drawings based on the foregoing description. The following examples are intended to illustrate the invention and are not intended to limit the scope of the invention.

Example  One: Hole transportation  Polymer manufacturing 1

First, 10,13-dibromo-3,6-bis (octyloxy) dibenzo [a, c] phenazine ) Were synthesized with reference to the following references (J. Am. Chem. Soc. 2014, 136, 427-435, J. Am. Chem. Soc., 2004, 126, 6035-6042).

0.1 g of synthesized 10-13-dibromo-3,6-bis (octyloxy) dibenzo [a, c] phenazine and 0.2 g of indacenodithieno-thiophene were dissolved in 8 ml And 0.009 g of tetrakistriphenylphosphinepalladium (II) dichloride (Aldrich) was added thereto. The mixture was stirred for 10 minutes and then at 90 ° C for 48 hours. Finally, 0.5 ml of bromothiophene (Aldrich) was added, and the mixture was stirred for 12 hours and purified to obtain 0.30 g of a hole transporting polymer represented by the following general formula (7).

(7)

Example  2: Hole transportation  Polymer manufacturing 2

First, 10,13-dibromo-2,7-bis (octyloxy) dibenzo [a, c] phenazine (10,13-dibromo-2,7- ) Were synthesized with reference to the following references (J. Am. Chem. Soc. 2014, 136, 427-435, J. Am. Chem. Soc., 2004, 126, 6035-6042).

0.069 g of synthesized 10-13-dibromo-2,7-bis (octyloxy) dibenzo [a, c] phenazine and 2,5-bis (trimethylstannyl) thiophene trimethylstannyl) thiophene (0.04 g) was dissolved in 8 ml of toluene, and 0.009 g of tetrakis (triphenylphosphine) palladium (II) dichloride (Aldrich) was added thereto. The mixture was stirred for 10 minutes, Respectively. Finally, 0.5 ml of bromothiophene (Aldrich) was added, and the mixture was stirred for 12 hours and purified to obtain 0.05 g of a hole transporting polymer represented by the following general formula (8).

[Chemical Formula 8]

Example  3: Organic photoelectric conversion device manufacturing 1

An organic photoelectric conversion device was fabricated using the hole transporting polymer prepared in Example 1 under the following conditions.

The surface of the substrate on which the ITO layer was formed on the transparent glass substrate was continuously ultrasonically irradiated and cleaned under acetone and isopropanol, dried at 100 캜 under vacuum for 1 hour, and then treated in a UV-ozone cleaner for 15 minutes.

The commercially available PEDOT: PSS (Heraeus Clevios ™ P VP AI 4083) was filtered using a 0.45 μm PTFE syringe filter and stirred in a shaker to prevent phase separation of PEDOT and PSS.

The hole transporting polymer according to Example 1 and fullerene were dissolved in dichlorobenzene at various concentrations and stirred for 24 hours and filtered using a 5 탆 PTFE syringe filter. Coated on the previously prepared ITO layer at a speed of 2000 rpm for 40 seconds.

The prepared substrate and samples were transferred to a glove box and spin-coated on the previously prepared ITO layer at a rate of 2000 rpm for 40 seconds. Then, PEDOT: PSS was subjected to heat treatment at 110 ° C for 20 minutes, AedotronTMC at 140 ° C for 20 minutes, and the polymer and fullerene active layer at 120 ° C for 1 hour to remove residual solvent. gave. Subsequently, the EIL and the electrode material were transferred to a high vacuum chamber (under 1 × 10 ^-6 torr) of a thermal evaporator for deposition of all the materials. BaF ₂ (0.1 Å / s, 2 nm) / Ba / s, 2 nm) / Al (5 Å / s, 100 nm).

Example  4: Organic photoelectric conversion device manufacturing 2

An organic photoelectric conversion device was manufactured in the same manner as in Example 3, except that Example 2 was used as a hole transporting polymer.

FIG. 1 is a cross-sectional view of the organic photoelectric conversion device manufactured in Examples 3 and 4.

Comparative Example  1: Organic photoelectric conversion device fabrication

An organic photoelectric conversion device was manufactured in the same manner as in Example 3, except that a polymer having the following structure (12) was used as a hole transporting polymer.

[Chemical Formula 12]

Comparative Example  2: Organic photoelectric conversion device manufacturing

An organic photoelectric conversion device was manufactured in the same manner as in Example 3, except that a polymer having the following structure (13) was used as a hole transporting polymer.

[Chemical Formula 13]

Experimental Example  One

The following experiments were conducted to evaluate the absorbance of the hole transporting polymer prepared in Examples 1 and 2.

The light absorption spectra were measured in the wavelength range of 300 nm to 1000 nm using the UV spectrum, and the results are shown in FIG. 2 and FIG.

Fig. 2 is a UV spectrum of the hole transporting polymer of Example 1, showing peaks on the film (Film in Fig. 2) and peaks in solution (Solution in Fig. 2). Referring to FIG. 2, a gentle peak in the solution phase can be confirmed on the film. This is due to the π-π stacking of the hole transporting polymer present in the film, which showed the possibility of effective charge transfer in the organic photoelectric conversion device.

FIG. 3 shows a light absorption spectrum of a film containing the hole transporting polymer of Example 2 shown in FIG. 3, and a film containing the hole transporting polymer of Example 2 shows a gentle light absorption curve .

As a result, it was found that the hole transporting polymer according to the present invention is extended to a long wavelength.

Experimental Example  2

A current potential curve was measured using the cyclic voltammetry at the scanning speed of 1 ㎷ / s in the organic photoelectric conversion device of Example 3, and the result is shown in FIG.

Experimental Example  3

The following experiment was conducted to evaluate the energy efficiency of the organic photoelectric conversion device according to the present invention.

The organic photoelectric conversion device manufactured in Example 3 was tested under standard conditions (Air Mass 1.5 Global, 100 mW / cm 2, 25 ° C) using a Keithley 2400 source meter and a solar simulator (Oriel 150W solar simulator) ), Short circuit current density (J _SC ), open circuit voltage (V _OC ), fill factor (FF), and power conversion efficiency (PCE) were measured. The artificial solar cell was tested with a Si solar cell (Mono-Si + KG filter, Certificate No. C-ISE269, Fraunhofer Institute for Solar Energy System) and the active area of the organic photoelectric conversion device was controlled to 12 mm 2. The measured results are shown in Table 1 below.

division J _SC (MA / cm2) V _OC (V) FF (%) PCE (%) Example 3 12.7 0.83 58.0 6.2 Comparative Example 1 8.00 0.83 56.57 3.75 Comparative Example 2 11.45 0.84 0.62 6.01

In Table 1, the fill factor (FF) is a voltage value at the maximum power point (V _max) X current density _{(J max) / (J SC} XV oc) , and the energy conversion efficiency (PCE) is FF X (J _SC XV _oc ) / Pin, and Pin is 100 [mW / cm < 2 >].

Table 1 shows that the organic photoelectric conversion device according to the present invention has improved energy conversion efficiency. Specifically, it can be confirmed that the energy conversion efficiency of the organic photoelectric conversion device can be improved by about 9% or more, which is close to the HOMO level (about 5.13 ± 0.1 eV), and the organic It can be seen that the photoelectric conversion element exhibits higher efficiency than the organic photoelectric conversion elements according to Comparative Examples 1 and 2.

5 is a graph showing the energy efficiency of the organic photoelectric conversion device manufactured according to the third embodiment. Referring to FIG. 5, the organic photoelectric conversion device according to the present invention shows high efficiency.

Claims (10)

A hole transporting polymer comprising a polymerization unit represented by the following formula (1):
[Chemical Formula 1]

In Formula 1,
M is a p-type molecule,
A is independently a single bond, alkylene having 1 to 20 carbon atoms, alkenylene having 2 to 20 carbon atoms, alkynylene having 2 to 20 carbon atoms, aralkylene having 7 to 15 carbon atoms, cycloalkylene having 3 to 20 carbon atoms , Alkynylene having 6 to 20 carbon atoms, arylene having 6 to 30 carbon atoms, ararylene having 7 to 20 carbon atoms, or heteroarylene having 4 to 20 carbon atoms,
R _a is independently hydrogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,
At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,
R _b is independently hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,
At least one of the hydrogen atoms present in the aryl group or the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,
and n is an integer of 1 to 1,000,000.
The method according to claim 1,
The hole transporting polymer comprising at least one polymerization unit selected from the group consisting of polymerization units represented by the following general formula (1-a) and general formula (1-b)
[Chemical Formula 1-a]

[Chemical Formula 1-b]

Wherein M, A, R _a , R _b and n are as defined in the above formula (1).
The method according to claim 1,
(P-type molecular) having electron-donating properties is a hole-transporting polymer comprising at least one selected from molecules represented by the following Chemical Formulas 2-a to 2-c:
[Chemical Formula 2-a]

[Formula 2-b]

[Chemical Formula 2-c]

In the above formulas 2-a to 2-c,
X ₁ to X ₄ independently of one another are O, S or Se,
Y ₁ and Y ₂ are independently of each other N or CR _d ,
R _c to R _e independently represent hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,
At least one of the hydrogen atoms present in the aryl group and the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms,
m and p are each independently an integer of 1 to 10;
The method of claim 3,
A p-type molecular having an electron-donating property is a hole-transporting polymer comprising a molecule represented by the following formula (2-a)
[Chemical Formula 2-a]

In the formula (2-a)
X ₁ is O, S or Se,
R _c is independently hydrogen or an alkyl group having 1 to 4 carbon atoms,
m is from 1 to 4;
5. The method of claim 4,
In formula (2-a), X ₁ is S,
R _c is independently hydrogen or an alkyl group having 1 to 4 carbon atoms,
m is 1, a hole transporting polymer.
The method of claim 3,
A p-type molecular having an electron-donating property is a hole-transporting polymer comprising a molecule represented by the following formula (2-b)
[Formula 2-b]

In the formula (2-b)
X ₂ and X ₃ are independently of each other O, S or Se,
Y ₁ and Y ₂ are independently of each other N or CR _d ,
R _d is hydrogen or an alkyl group having 1 to 25 carbon atoms,
p is one.
The method of claim 3,
A p-type molecular having an electron-donating property is a hole-transporting polymer comprising a molecule represented by the following formula (2-c)
[Chemical Formula 2-c]

In the formula (2-c)
X < ₄ > is O, S or Se,
R _e is independently hydrogen, halogen, an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 5 to 30 carbon atoms,
At least one of the hydrogen atoms present in the aryl group and the heteroaryl group is substituted or unsubstituted with an alkyl group having 1 to 25 carbon atoms, an alkoxy group having 1 to 25 carbon atoms, or an aryl group having 6 to 30 carbon atoms.
The method according to claim 1,
The hole transporting polymer comprising at least one polymerization unit selected from the group consisting of the polymerization units represented by the following formulas (3) to (6)
(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas 3 to 6,
A is a single bond or alkylene having 1 to 6 carbon atoms,
X ₅ and X ₆ are independently of each other O or S,
R _a and R _b independently represent hydrogen, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group or nonyloxy group,
R _c and R _e independently represent hydrogen, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a phenyl group, a naphthyl group, a pyrrolyl group or a thiazole group,
At least one of the hydrogen atoms present in the phenyl group, the naphthyl group, the pyrrolyl group and the thiazole group is substituted or unsubstituted with a pentyl group, a hexyl group, a heptyl group, an octyl group or a nonyl group,
and q is an integer of 1 to 1,000.
The method according to claim 1,
The hole transporting polymer comprising at least one polymerized unit selected from the group consisting of the following structural units represented by the following general formulas (7) and (8)
(7)

[Chemical Formula 8]

In the general formulas (7) and (8), r is an integer of 1 to 1,000.
A first electrode; A layer comprising a hole transporting polymer according to any one of claims 1 to 9; A photoelectric conversion layer; And a second electrode are stacked.

Images