KR101564406B1 - Novel Conjugated Polymer and Organo-Electronic Device Using the Same - Google Patents

Abstract

The present invention has the advantage of enhancing the open circuit voltage, lumen coefficient and efficiency by providing a conjugated polymer containing two or more benzodithiophenes in the main chain.

Description

TECHNICAL FIELD [0001] The present invention relates to novel conjugated polymers and organic electronic devices using the conjugated polymers.

The present invention relates to an organic electronic device, for example, an organic thin film transistor, an organic light emitting device, an organic optoelectronic device, a capacitor, and a sensor, which are manufactured by using a novel conjugated polymer in a charge transport layer.

Among the various renewable energy technologies, solar cells are receiving great attention because they can produce unlimited amounts of clean and safe energy. In the future, in order for the solar cell industry to become a major energy source in the future, it is necessary to develop low-cost solar cell technology that can dramatically lower the power generation unit cost. Therefore, organic thin film solar cell technology using a low cost organic material as a method for realizing a low production cost of a solar cell is attracting attention as a new alternative. The organic thin film solar cell uses a non-toxic organic material, and its device structure is simple and it is possible to fabricate the device by a solution process based on printing, so that the production cost can be lower than that of a silicon or inorganic thin film solar cell. In addition, when mass production of an organic thin film solar cell based on a large-area flexible substrate by a roll-to-roll process, a light and flexible organic thin film solar cell module can be produced at a low cost of less than $ 1.0 / Wp . Therefore, the organic thin film solar cell is expected to be able to create a new market in various application fields such as power generation for mobile devices and power generation for building exterior in the future, because it is superior in low cost, light weight, and flexibility characteristic compared with the conventional inorganic material based solar cell . Organic Thin Film Solar Cells In 1986, Dr. Tang Ph.D., a team of Dr. Koh Tae Kang of USA, presented organic thin film solar cells in the form of bilayer heterojunction based on p-type organic semiconductors CuPc (copper phthalocyanine) and perylene derivatives of n-type organic semiconductors And began to attract attention by announcing about 1% efficiency. Since then, various organic semiconducting materials have been used to increase the efficiency of the organic thin film solar cell, but the efficiency has remained low around 1%. In 1995, AJ Heeger and colleagues carried out a series of experiments using poly (phenylenevinylene) (PPV) -based p-type polymer as an electron donor and PCBM as a derivative of fluorene (C ₆₀ ) The efficiency of the solar cell was about 3%. Recently, various kinds of organic thin film solar cells, which have a photoactive layer by using a p-type polymer organic semiconductor such as poly (3-hexylthiophene) (P3HT) as an electron donor and a fluorene n-type semiconductor as an electron acceptor Is being developed.

C. W. Tang, App, Phys, Lett., 48, 183 (1986)

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and provides a novel conjugated polymer having excellent solubility and thermal stability and having high charge mobility.

The present invention also provides an organic semiconductor device employing a novel conjugated polymer according to the present invention.

The present invention provides a novel conjugated polymer which is excellent in electrical characteristics and thermal stability and high in solubility, and applicable to a solution process base.

Hereinafter, the conjugated polymer of the present invention will be described in detail.

The conjugated polymer of the present invention is represented by the following formula (1).

[Chemical Formula 1]

[In the above formula (1)

이며,A is

Lt;

B is (C ₆ -C ₂₀₎ arylene or (C ₃ -C ₂₀₎ heteroaryl is arylene,

Wherein R ₁ and R ₂ are independently of each other hydrogen, (C ₁ -C ₂₀ ) alkyl, (C ₆ -C ₂₀ ) aryl, (C ₃ -C ₂₀ ) heteroaryl or (C ₁ -C ₂₀ ) ,

Aryl or heteroaryl of R ₁ and R ₂ is (C ₁ -C ₂₀₎ alkyl which may be further substituted,

(C ₁ -C ₂₀ ) alkylcarbonyl, (C ₁ -C ₂₀ ) alkoxycarbonyl, halogen, (C ₁ -C ₂₀ ) alkyl, (C ₁ -C ₂₀ ) Alkoxy, amino, hydroxy, or nitro,

And a and b satisfy the condition of 2b ≤ a.

The substituents comprising the "alkyl", "alkoxy" and other "alkyl" moieties described in the present invention include both linear and branched forms, and "heteroaryl" refers to an aromatic ring skeleton atom such as B, N, P (= O), Si and P.

The conjugated polymer of the present invention can be used as a material of an organic electronic material, and the conjugated polymer is represented by the above formula (1).

More specifically, the conjugated polymer of the present invention has a structure in which dithiophene is fused to benzene, that is, benzodithiophene has a central structure, and thus has a high charge mobility due to its high electron density.

The present invention can achieve the intended effect of the present invention by satisfying the conditions of the above-mentioned polymerization units A and B satisfying 2b? A, and more preferably satisfying 3b? A? 10b. It is more preferable that the unit of a is 2 times, preferably 3 to 10 times, the unit of b.

In addition, the above-mentioned a and b satisfy the condition of 2b ≤ a, and preferably satisfy the condition of 3b ≤ a ≤ 10b so that the compound of the A structure becomes more in the main chain of the conjugated polymer, Has an effect of facilitating transfer, is excellent in thermal stability, and has a high charge mobility.

In the formula 1 of the present invention, when the condition of 2b ≤ a, more specifically, 3b ≤ a ≤ 10b is satisfied, the conjugated polymer is designated as A2B, wherein the a unit is twice the b unit and the A5B is the a unit b Which is five times the unit.

It is preferable that the formula (1) of the present invention has a weight average molecular weight of 10,000 to 500,000 g / mol in order to improve solubility in an organic solvent and high charge mobility.

In the conjugated polymer represented by the formula (1) of the present invention, A may be any one selected from, for example, compounds represented by the following formula (2), but is not limited thereto.

(2)

[In the formula (2)

R ₃ and R ₄ independently of one another are hydrogen or (C ₁ -C ₂₀ ) alkyl.

The above A has benzodithiophene as a central structure and has high charge mobility due to their high electron density. In addition, substituents A, B and C such as alkyl, alkoxy, thiophene and the like at the 4th and 8th positions of the benzene ring at the center of benzodithiophene By controlling the solubility of the polymer, the intermolecular packing, and the work function.

Examples of B in the conjugated polymer represented by Formula 1 of the present invention include, but are not limited to, one or more selected from the following Formula 3.

(3)

[Formula 3]

R ₅ to R ₁₄ are, independently of each other, (C ₁ -C ₂₀ ) alkoxy or (C ₁ -C ₂₀ ) alkyl.

The conjugated polymer of the present invention may be represented by the following general formulas (4) to (9), but is not limited thereto.

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

(7)

[Chemical Formula 8]

[Chemical Formula 9]

[Wherein R ₁₅ to R ₂₃ are each independently (C ₁ -C ₂₀ ) alkyl,

And a and b satisfy the condition of 2b ≤ a.

The following Reaction Scheme 1 shows an example of a method for synthesizing the conjugated polymer of the present invention, but the present invention is not limited thereto.

[Reaction Scheme 1]

In the above Reaction Scheme 1, a and b satisfy the condition of 2b? A, preferably 3b? A? 10b. That is, the number of compounds of the A structure increases in the main chain of the conjugated polymer of the present invention within a range where the a unit is 2 times or more, preferably 3 to 10 times, the b unit, and the hole transfer between the polymer main chains is smooth , Is excellent in thermal stability, and has a high charge mobility.

The conjugated polymer of the present invention is excellent in solubility and dispersibility and can be provided as a composition dissolved or dispersed in a liquid medium. The liquid medium includes an organic solvent. For example, the organic solvent may be any solvent selected from the group consisting of chloroform, chlorobenzene, and 1,2-dichlorobenzene, but is not limited thereto.

The conjugated polymer of the present invention can form a film by a process of dissolving it in an organic solvent to form a film, that is, by a solution process. Specifically, for example, the film may be formed by coating or coating by any one method selected from ink jet printing, spin coating, screen printing, and doctor blade, but is not limited thereto.

The conjugated polymer represented by Formula 4 of the present invention is a material for organic optoelectronic devices useful as a nonlinear optical material such as an organic light sensor (OPD), an organic light emitting diode (OLED), an organic thin film transistor (OTFT) useful.

In addition, the present invention includes a substrate, a first electrode, a buffer layer, a photoelectric conversion layer and jidoe composed of a second electrode, the photoelectric conversion layer is used as the conjugated system is an electron donor polymer according to the above embodiment, C ₆₀ fullerene derivative or There is provided an organic photoelectric device comprising a photoelectric conversion material in which a C ₇₀ fullerene derivative is combined with an electron acceptor, and an organic solar cell comprising the same.

As an example of the organic solar cell of the present invention, in a structure in which a substrate, a first electrode layer, a buffer layer, a photoelectric conversion layer, and a second electrode layer are laminated from the bottom, the photoelectric conversion layer is a structure in which the conjugated polymer according to the present invention is an electron donor used, and may include a C ₆₀ fullerene derivative C ₇₀ or a fullerene derivative is an organic photoelectric device formed in a solution containing a photoelectric conversion material formulated as an electron acceptor.

The conjugated polymer used as the electron donor of the organic optoelectronic device of the present invention can be obtained by introducing two or more benzodithiophene compounds, that is, the compound of the above formula (A), into the compound B to have low HOMO energy, Thermal stability is excellent, and ultimately, high energy conversion efficiency of the organic solar battery can be realized.

The substrate used in the organic solar cell of the present invention is preferably a transparent material such as glass or PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PI (polyamide), TAC Triacetyl cellulose), and more preferably glass.

The first electrode may be formed by applying a transparent material or coating a film on one surface of the substrate using a method such as sputtering or spin coating.

The first electrode may be used without particular limitation as long as it has transparency and conductivity. Preferred examples thereof include indium tin oxide (ITO), fluorine doped tin oxide (FTO), ZnO- (Ga2O3 or Al2O3), SnO2-Sb2O3, and more preferably ITO.

The buffer layer formed above the first electrode may improve hole mobility using poly (3,4-ethylenedioxythiophene) [PEDOT: PSS] doped with polystyrene sulfonate, wherein the work function It is possible to constitute a solar cell having a definite structure in which electrons fall into the second electrode using a small number of second electrodes. At this time, the method of forming the buffer layer can be introduced through a method such as spin coating.

A buffer layer of a low work function such as ZnO or the like is used on the first electrode and a second electrode having a large work function is used.

On the other hand, a photoelectric conversion layer is stacked on the buffer layer. The photoelectric conversion layer has a junction structure of an electron donor and an electron acceptor, and provides a photovoltaic power effect due to a very rapid charge transfer phenomenon between the electron donor and the electron acceptor.

In this case, the conjugated polymer of the present invention is used as the electron donor and the C ₆₀ fullerene derivative or the C ₇₀ fullerene derivative is used as the electron acceptor as the material of the photoelectric conversion layer.

The photoelectric conversion material of the photoelectric conversion layer of the present invention is preferably blended at a weight ratio of the conjugated polymer of the present invention to a C ₆₀ fullerene derivative or a C ₇₀ fullerene derivative in a weight ratio of 1: 0.5 to 1: 6. If the content of the fullerene derivative is less than 0.5 parts by weight, the content of the crystallized fullerene derivative is insufficient to cause the generation of electrons, and if the proportion of the fullerene derivative is more than 6 parts by weight, The amount of the semiconducting polymer is relatively reduced and the efficient absorption of light is not achieved.

The photoelectric conversion material in which the conjugated polymer of the present invention is combined with the C ₆₀ fullerene derivative or the C ₇₀ fullerene derivative may be dissolved in a single organic solvent or two or more organic solvents having different boiling points to prepare a solution. The organic solvent used may be any solvent selected from the group consisting of chloroform, chlorobenzene and 1,2-dichlorobenzene, and a solvent selected from the group consisting of 1,8-diiodooctane, 1-chlorobenzene and diphenyl ether And the solvent to be used may be mixed. The solid content of the photoelectric conversion material in the solvent is made to be 1.0 to 3.0 wt%. If the solid content is less than 1.0 wt%, there is a problem in maintaining the thickness of the introduced thin film at 80 nm or more. If the solid content is more than 3.0 wt%, the conjugated polymer and the C ₇₀ fullerene derivative do not melt, I can not.

Thereafter, the solution in which the photoelectric conversion material is dissolved is coated or coated by any one method selected from spin coating method, screen printing method, inkjet printing method and doctor blade method, and is coated with a solution of about 80 nm or more, Nm thick photoelectric conversion layer.

The second electrode may be deposited on the photoelectric conversion layer by vacuum thermal deposition of a metal material such as aluminum at a degree of vacuum of about 10 ^-7 torr or less while the photoelectric conversion layer is introduced. Examples of the material usable as the second electrode include gold, aluminum, copper, silver or their alloys, calcium / aluminum alloys, magnesium / silver alloys, aluminum / lithium alloys, Or an aluminum / calcium alloy may be used.

The conjugated polymer of the present invention has good solubility in an organic solvent, low HOMO level, excellent electrical properties and thermal stability.

In addition, the organic semiconductor device including the conjugated polymer of the present invention has high charge mobility and thus has excellent efficiency and performance.

1 is a UV-vis spectrum of a conjugated polymer according to Examples 1 to 4 and Comparative Example 1 in a chloroform solution.
2 is a UV-vis spectrum of the film state of the conjugated polymers according to Examples 1 to 4 and Comparative Example 1 of the present invention.
3 is a graph showing the current density-voltage (JV) characteristic values of organic solar cells manufactured according to Examples 1 to 4 and Comparative Example 1 of the present invention.
4 is a graph showing the external quantum efficiency of an organic solar cell fabricated according to Examples 1 to 4 and Comparative Example 1 of the present invention.
5 is a graph showing the photoelectric conversion energy efficiency according to the thickness of the organic solar cell fabricated according to Example 3 and Comparative Example 1 of the present invention.
6 is a UV-vis spectrum of the film state of the conjugated polymer according to Example 5 and Comparative Example 2 of the present invention.
7 is a UV-vis spectrum of the film state of the conjugated polymer according to Example 6 and Comparative Example 3 of the present invention.
8 is a UV-vis spectrum of the film state of the conjugated polymer according to Example 7 and Comparative Example 4 of the present invention.
9 is a UV-vis spectrum of film states of the conjugated polymers according to Example 8, Example 9, Comparative Example 5, and Comparative Example 6 of the present invention.
10 is a UV-vis spectrum of the film state of the conjugated polymers according to Example 10 and Comparative Example 7 of the present invention.

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples.

The following physical properties were measured by the following methods.

1) NMR Spectroscopy

¹ H NMR and ¹³ C NMR spectroscopy were measured using a Bruker AM-300 spectrometer.

2) Evaluation of optical characteristics

The UV-vis absorption spectrum was measured using a JASCO JP / V-570 model.

The solution state of the UV-vis absorption spectrum was measured by measuring the solution in which the polymer was dissolved in chloroform at a concentration of 1 × 10 ^-5 M, and the film state of the film was obtained by dissolving the polymer in a chlorobenzene solution and spin-

3) Molecular weight measurement

The molecular weight of the polymer was determined using gel permeation chromatography (GPC) Waters high-pressure GPC assembly Model M590 (polystyrene standard).

4) Electrochemical characterization (Cyclic Voltammetry: CV)

≪ / RTI > AUTOLAB / PGSTAT12.

Electrochemical cyclic voltammetry (CV) was extensively studied to investigate the redox properties of polymers and to break their HOMO and LUMO energy levels. Ag / Ag ⁺ electrode was used as a reference electrode and platinum wire was used as a counter electrode at room temperature. A 0.01 M AgNO ₃ solution was used as the electrolyte and the scanning speed was set to 50 ㎷ / s. The polymer film was immersed in a polymer solution and the electrode was immersed in a platinum electrode and air-dried. Three electrode elements were connected to the system and their electrochemical properties were measured.

5) Elemental analysis evaluation

Elemental analysis calcd (%) was measured with a Thermo FLASH EA-2000 instrument.

6) Evaluation of thermal properties

TA Instrument ' s TGA Q5000 V3.13 instrument.

The pyrolysis temperature (Td) was investigated by thermogravimetric analysis (TGA) and the temperature at which 5% weight loss occurred was measured.

[Manufacturing Example]

2- (2-ethylhexyl) thiophene (2) Am. Chem. Soc. 4, 8-bis (5- (2-ethylhexyl) thiophene-2-yl) benzo [1,2-b: 4,5-b`] dithiophene (4) Chem. Int. Ed. 2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophene-2-yl) benzo [1,2- b: 4,5 -b`] dithiophene (6) is Angew. Chem. Int. Ed. 2011, 50, 9697-9702.

2,6-Dibromo-4,8-bis (5- (2-ethylhexyl) thiophene-2-yl) benzo [1,2- b: 4,5- b`] dithiophene (5)

Benzo [1,2-b: 4,5-b] dithiophene (4) (4.54 mmol, 2.626 g) was added to a solution of 4,8-bis (5- (2- ethylhexyl) thiophene- Was dissolved in anhydrous THF (120 ml), and the reaction temperature was lowered to -78 ° C using dry ice / acetone. Then n-BuLi (9.98 mmol, 6.3 ml 1.6 M in hexane) was added dropwise. The mixture was stirred at -78 ° C for 1 hour and then at room temperature for 30 minutes. After the reaction temperature was lowered to -78 ° C, tetrabromomethane (9.98 mmol, 3.310 g) was added and the mixture was stirred for 1 hour and then stirred at room temperature for 12 hours. After completion of the reaction with 100 ml of water, the organic layer was dried by extraction with ether / water to obtain 2,6-Dibromo-4,8-bis (5- (2-ethylhexyl) thiophene-2-yl) benzo [ : 4,5-b`] dithiophene (yield = 70%).

^{1 H NMR (300 MHz, CDCl} 3) δ = 7.58 (s, 2H), 7.22 (d, 2H), 6.88 (d, 2H), 2.86 (d, 4H), 1.65 (m, 2H), 1.55-1.33 (br, 16H), 0.97-0.90 (t, 12H)

¹³ C NMR (300 MHz, CDCl ₃ )? = 146.37, 140.16,135.95,135.88,127.83,126.05,125.56,122.43,161.73,41.41,34.20,32.41,28.87,25.67,23.00,14.16,10.87

[Example 1]

Preparation of A2B polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (2-ethylhexyl) thiophen-2-yl) benzo [1,2-b: 4,5-b] dithiophene (0.1 mmol, 73.7 mg) was added to a solution of 2,6-Dibromo-4,8- 2-carboxylate (0.2 mmol, 94.4 mg) was dissolved in 10 ml of toluene and 2 ml of DMF. Then, after the argon purge for 30 _{minutes, [Pd (PPh 3) 4} ] it was purged with argon for a further addition of (0.012 m㏖, 14 ㎎) for 30 minutes to the mixture. Lt; RTI ID = 0.0 > 115 C < / RTI > for 36 hours. Then, the reaction temperature was lowered to room temperature, the reaction solution was poured into 200 ml of methanol, passed through a Soxhlet thimble, filtered, and extracted with Soxhlet with methanol, acetone, hexane and chloroform. Chloroform Soxhlet was extracted and the recovered polymer was precipitated in methanol and dried to obtain D2A (yield = 66.3%, 196.6 mg). Physical properties of the polymer synthesized by the above method are shown in Tables 1 to 3 below.

Elemental analysis calcd (%)

C ₈₃ H ₉₉ FO ₂ S ₁₀ : C = 67.89, H = 6.80, O = 2.18, S = 21.84

Found: C = 66.88, H = 6.67, O = 2.95, S = 21.35

[Example 2]

Preparation of A3B Polymer

In Example 1, 2,6-Dibromo-4,8-bis (5- (2-ethylhexyl) thiophene-2-yl) benzo [1,2- b: 4,5- b] dithiophene (0.15 mmol , 110.5 mg) and 2- (ethylhexyl) -4,6-dibromo-3-fluorothieno [3,4-b] thiophene-2-carboxylate (0.15 mmol, 70.9 mg) (Yield = 81.5%, 251.7 mg). The physical properties of the polymer synthesized as described above are shown in Tables 1 to 3 below. ≪ tb > < TABLE >

Elemental analysis calcd (%)

C ₁₁₇ H ₁₃₉ F O ₂ S ₁₄ : C = 68.71, H = 6.85, O = 1.56, S = 21.95

Found: C = 67.87, H = 6.75, O = 2.23, S = 21.52

[Example 3]

Preparation of A5B Polymer

In Example 1, 2,6-Dibromo-4,8-bis (5- (2-ethylhexyl) thiophene-2-yl) benzo [1,2-b: 4,5-b] dithiophene , 147.4 mg) and 2- (ethylhexyl) -4,6-dibromo-3-fluorothieno [3,4-b] thiophene-2-carboxylate (0.1 mmol, 47.2 mg) were heated / stirred at 115 ° C for 18 hours (Yield = 77.8%, 250 mg). The physical properties of the polymer synthesized in the same manner as above are shown in Tables 1 to 3 below.

Elemental analysis calcd (%)

C ₁₈₅ H ₂₁₉ FO ₂ S ₂₂ : C = 69.46, H = 6.90, O = 1.00, S = 22.05

Found: C = 69.40, H = 6.90, O = 1.15, S = 21.93

[Example 4]

Preparation of A7B Polymer

In Example 1, 2,6-Dibromo-4,8-bis (5- (2-ethylhexyl) thiophene-2-yl) benzo [1,2-b: 4,5-b] dithiophene (0.225 mmol , 165.8 mg) and 2- (ethylhexyl) -4,6-dibromo-3-fluorothieno [3,4-b] thiophene-2-carboxylate (0.075 mmol, 35.4 mg) (Yield = 64.4%, 210.9 mg). The physical properties of the polymer synthesized as described above are shown in Tables 1 to 3 below. ≪ tb > < TABLE >

Elemental analysis calcd (%)

C ₂₅₃ H ₂₉₉ FO ₂ S ₃₀ : C = 69.81, H = 6.92, O = 0.74, S = 22.10

Found: C = 69.72, H = 6.86, O = 1.08, S 21.82

[Example 5]

Preparation of TTK-5 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (2-ethylhexyl) thiophen-2-yl) benzo [1,2-b: 4,5-b] dithiophene (0.2 mmol, 147.4 mg) was added to a solution of 2,6-Dibromo-4,8- Synthesis was carried out in the same manner as in Example 1, using 2- (ethylhexyl) -4,6-dibromo-3-fluorothieno [3,4-b] thiophene-2-ketone (0.1 mmol, 42.4 mg) (Yield: 79.8%, 253.7 mg). UV-vis spectral results of the film state of the TTK-5 are shown in FIG.

Weight average molecular weight = 65,700 g / mol

Polydispersity index = 4.260

Polydispersity Index: Poly Dispersity Index, PDI

[Example 6]

Preparation of TPD-5 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (2-ethylhexyl) thiophen-2-yl) benzo [1,2-b: 4,5-b] dithiophene (0.2 mmol, 147.4 mg) was added to a solution of 2,6-Dibromo-4,8- (0.1 mmol, 42.3 mg) was used in place of 1,3-dibromo-5-octyl-4H-thieno [3,4-c] pyrrole-4,6 (Yield: 47.6%, 151.3 mg). UV-vis spectral results of the film state of TPD-5 are shown in FIG.

Weight average molecular weight = 53,700 g / mol

Polydispersity index = 4.313

Polydispersity Index: Poly Dispersity Index, PDI

[Example 7]

Preparation of iIn-5 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- b] dithiophene (0.25 mmol, Dibromo-4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.166 mmol, 122.5 (E) -2,2'-dibromo-4,4'-bis (2-octyldodecyl) - [6,6'-bithieno [3,2-b] pyrrolidene] -5,5 ' 4`H) -dione (0.084 m㏖, 82.6 ㎎) and _{[Pd (PPh 3) 4]} (0.010 m㏖, 12 ㎎) using a synthesized in the same manner as in example 1 to obtain a iIn-5. (Yield: 45.7%, 141 mg) The UV-vis spectral results of the film state of iIn-5 are shown in FIG.

Weight average molecular weight = 121,900 g / mol

Polydispersity index = 2.777

Polydispersity Index: Poly Dispersity Index, PDI

[Example 8]

Preparation of DPP-BO-5 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (2-ethylhexyl) thiophen-2-yl) benzo [1,2-b: 4,5-b] dithiophene (0.2 mmol, 147.4 mg) was added to a solution of 2,6-Dibromo-4,8- 2-yl) -2,5-bis (2-butyloctyl) -2,5-dihydropyrrolo [3,4-c] pyrrole-1,4-dione (yield: 68.7%, 242 mg). The UV-vis spectrum of the DPP-BO-5 in the film state was measured by the same method as in Example 1, The results are shown in Fig.

Weight average molecular weight = 55,700 g / mol

Polydispersity index = 2.145

Polydispersity Index: Poly Dispersity Index, PDI

[Example 9]

Preparation of DPP-EH-5 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (2-ethylhexyl) thiophen-2-yl) benzo [1,2-b: 4,5-b] dithiophene (0.2 mmol, 147.4 mg) was added to a solution of 2,6-Dibromo-4,8- 2-ethylhexyl) -2,5-dihydropyrrolo [3,4-c] pyrrole-1,4-dione (0.1 g) was added to a solution of 3,6-bis (5-bromothiophene- (yield: 82.7%, 281.8 mg). The UV-vis spectra of the film state of DPP-EH-5 were measured using the same method as in Example 1, The results are shown in Fig.

Weight average molecular weight = 86,500 g / mol

Polydispersity Index = 4.505

Polydispersity Index: Poly Dispersity Index, PDI

[Example 10]

Preparation of TP-5 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (2-ethylhexyl) thiophen-2-yl) benzo [1,2-b: 4,5-b] dithiophene (0.2 mmol, 147.4 mg) was added to a solution of 2,6-Dibromo-4,8- (0.1 mmol, 70.3 mg) was used in place of 5,7-dibromo-2,3-bis (3- (octyloxy) phenyl) thieno [3,4- b] pyrazine (Yield: 94.8%, 325 mg). UV-vis spectral results of the film state of TP-5 are shown in FIG.

Weight average molecular weight = 67,200 g / mol

Polydispersity index = 3.854

Polydispersity Index: Poly Dispersity Index, PDI

[Comparative Example 1]

Preparation of A1B polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 2-carboxylate (0.3 mmol, 141.7 mg) was dissolved in 10 ml of toluene and 2 ml of DMF. Then, after the argon purge for 30 _{minutes, [Pd (PPh 3) 4} ] it was purged with argon for a further addition of (0.012 m㏖, 14 ㎎) for 30 minutes to the mixture. Lt; RTI ID = 0.0 > 115 C < / RTI > for 36 hours. Then, the reaction temperature was lowered to room temperature, the reaction solution was poured into 200 ml of methanol, passed through a Soxhlet thimble, filtered, and extracted with Soxhlet with methanol, acetone, hexane and chloroform. Chloroform Soxhlet was extracted and the recovered polymer was precipitated in methanol and dried to obtain D1A (yield = 74.7%, 202.7 mg). Physical properties of the polymer synthesized by the above method are shown in Tables 1 to 3 below.

Elemental analysis calcd (%)

C ₄₉ H ₅₉ FO ₂ S ₆ : C = 66.02, H = 6.67, O = 3.59, S = 21.58

Found: C = 65.42, H = 6.46, O = 4.76, S = 21.23

[Comparative Example 2]

Preparation of TTK-1 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 Synthesis was carried out in the same manner as in Comparative Example 1, using 2- (ethylhexyl) -4,6-dibromo-3-fluorothieno [3,4-b] thiophene-2-ketone (0.3 mmol, (Yield: 93.7%, 242 mg). UV-vis spectral results of the film state of the TTK-1 are shown in FIG.

Weight average molecular weight = 157,768 g / mol

Polydispersity index = 1.740

Polydispersity Index: Poly Dispersity Index, PDI

[Comparative Example 3]

Preparation of TPD-1 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (0.3 mmol, 126.9 mg) was used in place of 1,3-dibromo-5-octyl-4H-thieno [3,4-c] pyrrole-4,6 (Yield: 75%, 189.5 mg). UV-vis spectral results of the film state of TPD-1 are shown in FIG.

Weight average molecular weight = 20,800 g / mol

Polydispersity index = 1.68

Polydispersity Index: Poly Dispersity Index, PDI

[Comparative Example 4]

Preparation of iIn-1 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- b] dithiophene (0.25 mmol, (E) -2,2'-dibromo-4,4'-bis (2-octyldodecyl) - [6,6'-bithieno [3,2-b] pyrrolidene] -5,5 ' 4`H) -dione (0.25 m㏖, 248.3 ㎎), [Pd (PPh 3) 4] (0.010 m㏖, 12 ㎎) using a synthesized in the same manner as in Comparative example 1 to give the iIn-1. (Yield: 70%, 247.2 mg) The UV-vis spectral results of the film state of iIn-1 are shown in FIG.

Weight average molecular weight = 43,900 g / mol

Polydispersity index = 1.68

Polydispersity Index: Poly Dispersity Index, PDI

[Comparative Example 5]

Preparation of DPP-BO-1 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 2-yl) -2,5-bis (2-butyloctyl) -2,5-dihydropyrrolo [3,4-c] pyrrole-1,4-dione (0.3 (yield: 95.3%, 346.9 mg). The UV-vis spectrum of the film state of the DPP-BO-1 was measured by the same method as in the above Comparative Example 1, The results are shown in Fig.

Weight average molecular weight = 250,950 g / mol

Polydispersity index = 5.084

Polydispersity Index: Poly Dispersity Index, PDI

[Comparative Example 6]

Preparation of DPP-EH-1 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 2-ethylhexyl) -2,5-dihydropyrrolo [3,4-c] pyrrole-1,4-dione (0.3 g) was added to a solution of 3,6-bis (5-bromothiophene- (yield: 20%, 66.1 mg). The UV-vis spectrum of the film state of the DPP-EH-1 was measured by the same method as in Comparative Example 1, The results are shown in Fig.

Weight average molecular weight = 67,500 g / mol

Polydispersity index = 2

Polydispersity Index: Poly Dispersity Index, PDI

[Comparative Example 7]

Preparation of TP-1 Polymer

2,6-bis (trimethyltin) -4,8-bis (5- (2-ethylhexyl) thiophen-2-yl) benzo [1,2- b: 4,5- bldithiophene (0.3 mmol, 271.4 (0.3 mmol, 210.8 mg) was used instead of 5,7-dibromo-2,3-bis (3- (octyloxy) phenyl) thieno [3,4- b] pyrazine (Yield: 61.8%, 207.5 mg) The UV-vis spectral results of the film state of TP-1 are shown in FIG.

Weight average molecular weight = 50,100 g / mol

Polydispersity index = 2.174

Polydispersity Index: Poly Dispersity Index, PDI

[Table 1] Analysis of Examples 1 to 4 and Comparative Example 1

[Table 2] Electrical and optical properties of Examples 1 to 4 and Comparative Example 1

(a): 1 x 10 < ^-5 > M concentration in anhydrous chloroform

(b): A solution in chlorobenzene was spin-cast at 1500 rpm for 30 seconds to polymer film on quartz plate

(c): calculated from the absorption band edge of the polymer film (E _g = 1240 / λ _edge )

(d): The Ag / Ag ⁺ electrode was used as the reference electrode, and the reference was set as 0.21 eV for ferrocene in 0.01M AgNO ₃ solution

(e): assuming that the energy level of ferrocene is 4.8 eV, HOMO = - (4.8 + E ^ox _onset ) eV

(f): LUMO = (HOMO + E _g ^opt )

[Table 3] Photoelectric properties of Examples 1 to 4 and Comparative Example 1

Photovoltaic properties

The photoelectric device was fabricated using a polymer obtained from the above Examples and Comparative Examples as a p-type electron donor and a PC ₇₀ BM (EM index company) as an n-type acceptor. The polymer and PC ₇₀ BM were dissolved in a mixed solvent of chlorobenzene and 1,8-diiodooctane at a weight ratio of 1: 1.15. Photoelectric devices were fabricated and characterized by ITO / PEDOT: PSS / Polymer + PC ₇₀ BM (1: 1.5 weight ratio) / Ca / Al device structure.

The conjugated polymer of the present invention exhibits excellent photoelectric performance. The open-circuit voltages (V _oc ) in Examples 1 to 4 are 0.80 V, 0.80 V, 0.80 V, and 0.82 V, respectively. In addition, the tightness coefficients (FF) of Examples 1 to 4 are 0.65 mm, 0.67 mm, 0.70 mm, and 0.69 mm, respectively. On the other hand, the open-circuit voltage (V _oc ) of Comparative Example 1 is 0.77 V, and the fill factor (FF) is 0.63 mm. Therefore, the energy conversion efficiencies of Examples 1 to 4 of the present invention were as high as 6.37%, 6.27%, 6.52%, and 6.04%, respectively, and the energy conversion efficiencies of the energy conversion efficiency were as high as two or more A structures in the main chain, It is believed that this is due to the effect of smooth transferring of holes in the liver.

In addition, it was confirmed that the conjugated polymer of the present invention is suitable as a material for an organic solar battery.

In the drawings of the present invention,

As can be seen from the UV-vis spectra of FIGS. 1, 2 and 6 to 10, as the number of compounds of the structure A increases, the light of a short wavelength can be selectively absorbed. By changing the content of the structure A, Can be adjusted.

Figure 3 Examples 1 to 4 and the JV curve of the organic solar cell device manufactured by using a synthetic polymer according to Comparative Example 1, and a high open-circuit voltage (V _oc) for A2B to A7B compared to A1B It shows higher efficiency with high packing factor (FF).

FIG. 4 shows the external quantum efficiency of the organic solar cell using the materials according to Examples 1 to 4 and Comparative Example 1, showing that the absorption region shifts to a shorter wavelength region as the content of the A structure increases.

FIG. 5 is a graph showing the photoelectric conversion energy efficiency according to the thickness of an organic solar cell fabricated using the material synthesized according to Example 3 and Comparative Example 1. The efficiency of the device manufactured using the A5B material, regardless of the thickness, A1B < / RTI >

Claims (8)

A conjugated polymer represented by the following formula (1).
[Chemical Formula 1]

[In the above formula (1)
A is any one selected from the following compounds,

B is (C ₆ -C ₂₀₎ arylene or (C ₃ -C ₂₀₎ heteroaryl is arylene,
Wherein R ₃ and R ₄ are independently of each other hydrogen or (C ₁ -C ₂₀ ) alkyl,
(C ₁ -C ₂₀ ) alkylcarbonyl, (C ₁ -C ₂₀ ) alkoxycarbonyl, halogen, (C ₁ -C ₂₀ ) alkyl, (C ₁ -C ₂₀ ) Alkoxy, amino, hydroxy, or nitro,
And a and b satisfy the condition of 2b ≤ a. The method according to claim 1,
Wherein a and b satisfy the condition of 3b ≤ a ≤ 10b. The method according to claim 1,
Wherein the weight average molecular weight of Formula 1 is 10,000 to 500,000 g / mol. delete The method according to claim 1,
And B is one or more selected from the following general formula (3).
(3)

[Formula 3]
R ₅ to R ₁₄ are, independently of each other, (C ₁ -C ₂₀ ) alkoxy or (C ₁ -C ₂₀ ) alkyl. The method according to claim 1,
Wherein the formula (1) is represented by the following formulas (4) to (9).
[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

(7)

[Chemical Formula 8]

[Chemical Formula 9]

[Wherein R ₁₅ to R ₂₃ are each independently (C ₁ -C ₂₀ ) alkyl,
And a and b satisfy the condition of 2b ≤ a. An organic electronic device comprising a conjugated polymer according to any one of claims 1 to 3 and 5 to 6. An organic solar battery comprising a substrate, a first electrode layer, a buffer layer, a photoelectric conversion layer and a second electrode layer, wherein the photoelectric conversion layer comprises a conjugated polymer according to any one of claims 1 to 3 Features Organic solar cell.

Images