KR20230084034A - Effective near-infrared absorbing electron donor material and near-infrared sensitive organic electronic device using thereof - Google Patents

Abstract

The present invention relates to an effective near-infrared absorbing electron donor material and a near-infrared sensitive organic electronic device using the same. The effective near-infrared absorbing electron donor material and a near-infrared sensitive organic electronic device using the same according to the present invention can easily perform solubility adjustment for a solution process and optical-electrical deformation. Accordingly, the present invention can effectively absorb infrared light having a long wavelength and expect a high light absorption degree. In addition, it is expected to form effective crystallinity for an increase in the stacking of molecules and the improvement of electron transfer due to fusion-type great flatness and low steric hindrance effects. In addition, thienopyrazine-based polymer compounds have an increased intermolecular interaction (ICT) effect, thereby obtaining a much stronger infrared absorbing material.

Description

Effective near-infrared absorbing electron donor material and near-infrared sensitive organic electronic device using the same

The present invention relates to an effective near-infrared ray absorbing material and a near-infrared ray-sensitive organic electronic device, particularly an organic photoelectric conversion device using the same.

The low-bandgap material has a strong quinoid structure and electron donor characteristics, and dipyrrolopyrrole (DPP), thienothiadiazole (TTz), and bisbenzothiadiazole ( Bisbenzothiadiazole, BBT) is mainly used as an effective near-infrared absorbing material (non-patent literature, Tian, He; Qu, Sanyin, Chemical Communications . 48 (25): 3039-3051).

However, most infrared absorbing materials have low external quantum efficiency in the infrared region because it is difficult for photons absorbed in the infrared region to be extracted and moved to charge carriers.

In addition, synthesis is difficult, oxidation stability is low due to high HOMO energy position, and solution processing and optical-electrical property change are difficult due to the lack of introduction of alkyl chains and diversity of structural transformation in some materials.

In order to solve this problem, an electron donor ( electron donors were invented.

One object of the present invention is to provide a novel near-infrared ray absorbing material.

Another object of the present invention is to provide a near-infrared ray sensitive organic electronic device using the near-infrared absorbing material.

In order to achieve the above purpose,

In one aspect, the present invention provides a near-infrared ray absorbing material using Thienopyrazine (TPZ), and specifically provides an electron donor material.

On another aspect,

A near-infrared ray sensitive organic device using the near-infrared absorbing material, specifically an organic photoelectric conversion device is provided.

The near-infrared ray absorbing material and the near-infrared ray-sensitive organic electronic device using the same according to the present invention are easy to adjust solubility and optical-electrical transformation for a solution process. Due to these characteristics, it can effectively absorb light in the long wavelength and infrared region, and high light absorption can be expected. In addition, it can be expected to form effective crystallinity for increasing intermolecular stacking and improving electron movement due to the excellent planarity and low steric hindrance effect of the fusion form. In addition, the cyenopyrazine-based tombs according to the present invention have an increased intermolecular interaction (ICT) effect, enabling much stronger infrared absorption.

1 shows the result of measuring the absorption spectrum for P-1, which is an example.
Figure 2 shows the result of measuring the absorption spectrum for P-2, which is an embodiment.
Figure 3 shows the result of measuring the absorption spectrum for P-3, which is an embodiment.
Figure 4 shows the result of measuring the absorption spectrum for P-4, which is an embodiment.

Hereinafter, the present invention will be described in detail.

Meanwhile, the embodiments of the present invention may be modified in various forms, and the scope of the present invention is not limited to the embodiments described below. In addition, the embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

Furthermore, "include" a certain component throughout the specification means that other components may be further included without excluding other components unless otherwise stated.

In this specification, “alkyl” means a monovalent radical as a substituent containing all structural isomers of straight or branched chain as a completely saturated hydrocarbon. When C1-C30 alkyl, it means that the number of carbon atoms constituting the hydrocarbon ranges from 1 to 30.

In the present specification, "halogen" is an element belonging to group 7 on the periodic table of elements, and refers to a monovalent radical as a substituent containing all of fluoro, chloro, bromo, and iodo.

One aspect of the present invention,

A near-infrared ray absorbing material using thienopyrazine (TPZ) is provided.

The absorber material may be a donor material or an acceptor material.

As one specific example of the present invention,

The donor material includes an infrared ray absorbing polymer compound including a repeating unit represented by Formula 1 below.

[Formula 1]

In Formula 1,

A is not present or is any one selected from Formulas 2 to 4 below,

R ¹ to R ⁴ are each independently hydrogen, halogen or C1-C30 alkyl;

[Formula 2]

[Formula 3]

[Formula 4]

here,

R ^5a , R ^5b , R ^6a , R ^6b , R ^7a , and R ^7b are each independently

hydrogen, C1-C30 alkyl or halogen.

In another embodiment, it may be as follows.

R ¹ to R ⁴ are each independently hydrogen, halogen or C4-C20 alkyl;

R ¹ to R ⁴ are each independently hydrogen, halogen or C4-C20 alkyl;

R ¹ to R ² are each independently hydrogen or C4-C20 alkyl and/or R ³ to R ⁴ are each halogen;

The R ¹ to R ² are the same, and/or the R ³ to R ⁴ are the same.

R ^5a , R ^5b , R ^6a , R ^6b , R ^7a , and R ^7b are each independently C1-C30 alkyl or halogen;

R ^5a , R ^5b , R ^6a , R ^6b , R ^7a , and R ^7b are each independently C4-C20 alkyl or halogen.

In another embodiment of the invention,

The polymer compound of Formula 1,

A may not exist, in which case

R ¹ to R ⁴ may each independently be C1-C30 alkyl or C1-C20 alkyl.

At this time, R ¹ to R ² may be the same and/or R ³ to R ⁴ may be the same.

In another embodiment of the invention,

The polymer compound of Formula 1,

A is Formula 2, wherein

R ¹ to R ⁴ may each independently be C1-C30 alkyl or C4-C20 alkyl, wherein R ¹ to R ² may be the same and/or R ³ to R ⁴ may be the same,

^R5a and ^R5b may each be halogen, R ^5a and R ^5b may be the same.

In another embodiment of the invention,

The polymer compound of Formula 1,

A is Formula 3, wherein

R ¹ to R ² are each independently C1-C30 alkyl or C4-C20 alkyl;

In this case, R ¹ to R ² may be the same,

R ³ to R ⁴ are each hydrogen;

R ^6a and R ^6b may each be C1-C30 alkyl or C4-C20 alkyl;

In this case, R ^6a and R ^6b may be the same.

In another embodiment of the invention,

The polymer compound of Formula 1,

A is Formula 4,

R ¹ to R ² are each independently halogen, wherein R ¹ to R ² may be the same;

R ³ to R ⁴ are each independently hydrogen;

R ^7a and R ^7b are each independently C1-C30 alkyl or C4-C20 alkyl, wherein R ^7a and R ^7b may be the same.

In another embodiment of the invention,

The polymer compound represented by Chemical Formula 1 may be selected from the following.

,

,

,

,

,

,

In another aspect of the present invention,

A method for preparing a polymer compound according to the present invention is provided.

In one embodiment,

Provided is a method for preparing a polymer compound according to Formula 1, including polymerization of a monomer represented by Formula 1A and a monomer represented by Formula 1C.

[Formula 1A]

[Formula 1C] X ² -AX ²

wherein X ¹ is halogen, X2 is Me ₃ Sn,

A, R ¹ to R ⁴ are as defined above with respect to Formula 1.

Preferably,

A may not exist or may be Formula 2,

When A is absent, the monomer according to Formula 1C does not contribute to the polymer.

In another embodiment,

Provided is a method for preparing a polymer compound according to Formula 1, including polymerization of a monomer represented by Formula 1A and a monomer represented by Formula 1C.

[Formula 1A]

[Formula 1C] X ² -AX ²

Here, X ¹ is Me ₃ Sn, X ² is halogen,

A, R ¹ to R ⁴ are as defined in claim 1,

Preferably, A may be of Formula 3.

In another embodiment,

A method for producing a polymer compound according to Chemical Formula 1, including polymerization of a monomer represented by Chemical Formula 1D and a monomer represented by Chemical Formula 1E, is provided.

[Formula 1D]

[Formula 1E]

wherein X ³ is halogen, X ⁴ is -SnMe ₃ ,

R ¹ to R ⁴ are as defined in claim 1,

Preferably, A may be of Formula 4.

The polymer compound has a weight average molecular weight of 1,000 to 200,000.

Hereinafter, the present invention will be described in detail through Examples and Experimental Examples.

However, the examples and experimental examples to be described later are only to specifically illustrate the present invention in one aspect, but the present invention is not limited thereto.

< Example 1> Preparation of P-1 High Polymer

1-1. 5,7-bis (5-bromothiophen-2-yl) -2,3-bis (2-ethylhexyl) thieno [3,4-b] pyrazine (5,7-bis (5-bromothiophen Synthesis of -2-yl)-2,3-bis(2-ethylhexyl)thieno[3,4-b]pyrazine)

[Scheme 1-1]

0.6 g (1.1 mmol) of 2,3-bis (2-ethylhexyl) -5,7-di (thiophen-2-yl) in 15 ml of anhydrous tetrahydrofurane (THF) in an argon atmosphere flask. Add thio[3,4-b]pyrazine (2,3-bis(2-ethylhexyl)-5,7-di(thiophen-2-yl)thieno[3,4-b]pyrazine) to -78℃. lower the temperature After adding 1.5 mL (2.8 mmol) of lithium diisopropylamide solution (LDA solution 2.0 M in THF/heptane/ethylbenzene) at a concentration of 2.0 mol (M) and stirring for 30 minutes, again at -78 ℃ N- After adding 672 mg (2.7 mmol) of N-bromosuccinimide (NBS), the mixture was stirred at room temperature for 1 hour. Thereafter, water was added to terminate the reaction, and the organic layer was extracted using methylene chloride as a solvent. After the organic layer was dehydrated with anhydrous magnesium sulfate (MgSO ₄ ), the solvent was removed using a rotary evaporator, and the residue was purified through column chromatography using hexane:methylene chloride (1:1) as a solvent mobile phase to obtain pure 5,7-bis ( 5-bromothiophen-2-yl) -2,3-bis (2-ethylhexyl) thieno [3,4-b] pyrazine (5,7-bis (5-bromothiophen-2-yl) - 2,3-bis(2-ethylhexyl)thieno[3,4-b]pyrazine) 200mg (25%) was obtained.

1-2. Preparation of P-1 High Polymer

[Scheme 1-2]

Compound 4,8-bis(5-(2-ethylhexyl)-thiophen-2-yl)-benzo[1,2-b:4,5 b']dithiophene-2,6-dinyl)bis (trimethylsten) (4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5 b']dithiophene-2,6-diyl)bis(trimethylstannane) 53.5 mg (0.05 mmol), 5,7-bis (5-bromothiophen-2-yl) -2,3-bis (2-ethylhexyl) thieno [3,4-b] pyrazine (5, 40.4 mg (0.05 mmol) of 7-bis(5-bromothiophen-2-yl)-2,3-bis(2-ethylhexyl)thieno[3,4-b]pyrazine) and tetrakis(triphenylphosphine) with a palladium catalyst ) Put 2.7 mg (4 mol%) of palladium (Pd(PPh ₃ ) ₄ , Tetrakis(triphenylphosphine)palladium(0)) into a reaction tube in a glove box and close the stopper. Using a syringe, inject 0.8 ml of anhydrous toluene and 0.2 ml of anhydrous dimethylformimide (DMF), purging the solvent in an argon atmosphere for 10 minutes, and then reacting in a reactor at 110 ° C for 3 hours. . After precipitating the reaction solution in 50 mL of methanol, the precipitated solid is recovered through a filter. The recovered precipitate was filtered through a Soxhlet thimble, followed by Soxhlet extraction with methanol, acetone, hexane, methylene chloride, and chloroform solvents. The chloroform Soxhlet-extracted solution was concentrated, precipitated in methanol, and dried to obtain a high-molecular weight polymer. The polymer yield = 53%, 30 mg.

< Example 2> Preparation of P-2 High Polymer

[Scheme 2]

Compound 5,7-bis (5-bromo-3-hexylthiophen-2-yl) -2,3-bis (2-ethylhexyl) thieno [3,4-b] pyrazine 85.1 mg (0.1 mmol ), hexylmethylditin (hexylmethylditin) 36.1 mg (0.11 mmol), potassium acetate (potassium acetate) 63.7 mg (0.65 mmol) and tetrakis (triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ , Tetrakis (triphenylphosphine) palladium (0)) 4.6 mg (4 mol%) was put in a reaction tube in a glove box and the stopper was closed. 2 mL of anhydrous toluene was injected using a syringe, and the solvent was purged in an argon atmosphere for 10 minutes, followed by reaction in a reactor at 110° C. for 36 hours. After precipitating the reaction solution in 50 mL of methanol, the precipitated solid is recovered through a filter. The recovered precipitate was filtered through a Soxhlet thimble, followed by Soxhlet extraction with methanol, acetone, hexane, methylene chloride, and chloroform solvents. The chloroform Soxhlet-extracted solution was concentrated, precipitated in methanol, and dried to obtain a high-molecular weight polymer. The polymer yield = 29%, 25 mg.

< Example 3> Preparation of P-3 High Polymer

3-1. 2,3-bis (2-ethylhexal) -5,7-bis (3-hexyl-5- (trimethylstenyl) thiophen-2-yl) thieno [3,4-b] pyrazine (2, Synthesis of 3-bis(2-ethylhexyl)-5,7-bis(3-hexyl-5-(trimethylstannyl)thiophen-2-yl)thieno[3,4-b]pyrazine)

[Scheme 3-1]

250 mg of 2,3-bis(2-ethylhexyl)-5,7-bis(3-hexylthiophen-2-yl)thiophene[3,4-b]pyrazine (2,3-bis(2- After dissolving ethylhexyl) -5,7-bis (3-hexylthiophen-2-yl) thieno [3,4-b] pyrazine) with 5 mL of tetrahydrofuran (THF, tetrahydrofurane), the temperature is lowered to -78 ° C. . 2.0 mole (M) lithium diisopropylamide solution (lithium diisopropylamide solution, LDA solution 2.0 M in THF/heptane/ethylbenzene) 0.42 mL (0.82 mmol) was added, stirred for 30 minutes, and then 1 mole (M) at -78 ° C again. ) concentration of trimethyltin chloride solution (Trimethyltin chloride solution 1.0 M in THF) into 1.1 mL (1.08 mmol) and stir at room temperature for 1.5 hours. Thereafter, water was added to terminate the reaction, and the organic layer was extracted using ethyl acetate as a solvent. After the organic layer was dehydrated with anhydrous magnesium sulfate (MgSO ₄ ), the solvent was removed using a rotary evaporator. Through recrystallization using chloroform and ethanol, pure purple crystalline solid 2,3-bis(2-ethylhexyl)-5,7-bis(3-hexyl-5-(trimethylstenyl)thiophen-2-yl) between No[3,4-b]pyrazine (2,3-bis(2-ethylhexyl)-5,7-bis(3-hexyl-5-(trimethylstannyl)thiophen-2-yl)thieno[3,4-b] pyrazine) to obtain 130 mg (35%).

3-2. Preparation of P-3 polymer polymer

[Scheme 3-2]

Compound 2,3-bis (2-ethylhexyl) -5,7-bis (3-hexyl-5- (trimethylstenyl) thiophen-2-yl) thieno [3,4-b] pyrazine (2 ,3-bis(2-ethylhexyl)-5,7-bis(3-hexyl-5-(trimethylstannyl)thiophen-2-yl)thieno[3,4-b]pyrazine) 110 mg (0.1 mmol), 4, 7-dibromo-5,6-difluorobenzene [c][1,2,5]thiadiazole (4,7-dibromo-5,6-difluorobenzo[c][1,2,5]thiadiazole ) 35.6 mg (0.1 mmol) and 4.5 mg (5 mol%) of tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ , Tris(dibenzylideneacetone)dipalladium(0)) as a palladium catalyst and ligand 3.5 mg (10 mol%) of tri(o-tolyl)phosphine (P(o-tol) ₃ , Tri(o-tolyl)phosphine) was put into a reaction tube in a glovebox and the stopper was closed. 0.5 mL of anhydrous chlorobenzene (CB) was injected using a syringe, and the solvent was purged in an argon atmosphere for 10 minutes, followed by reaction in a reactor at 110° C. for 36 hours. After precipitating the reaction solution in 50 mL of methanol, the precipitated solid is recovered through a filter. The recovered precipitate was filtered through a Soxhlet thimble, followed by Soxhlet extraction with methanol, acetone, hexane, methylene chloride, and chloroform solvents. The chloroform Soxhlet-extracted solution was concentrated, precipitated in methanol, and dried to obtain a high-molecular weight polymer. The polymer yield = 22%, 20 mg.

< Example 4> Preparation of P-4 polymer polymer

4-1. Synthesis of 5,7-dibromo-2,3-dichloro[3,4-b]pyrazine

[Scheme 4-1]

In an argon atmosphere, 1 g (3.1 mmol) of 5,7-dibromothieno[3,4-b]pyrazine-2,3(1H,4H)-dione (5,7-dibromothieno[3,4-b After dissolving ]pyrazine-2,3(1H,4H)-dione) in 20 mL of chloroform (CF), 1.6 g of thionyl chloride and 0.5 g of dimethylformimide (DMF) at 0 ^o C. After injecting mL, reflux and stir. After about 2 hours, the reaction was terminated with water, and the organic layer was extracted with chloroform. After the organic layer was dehydrated with anhydrous magnesium sulfate (MgSO ₄ ), the solvent was removed using a rotary evaporator, and the residue was purified through column chromatography using hexane:methylene chloride (2:1) as a solvent mobile phase to obtain pure 5,7-dibromo. Obtained 380 mg (33%) of -2,3-dichloro[3,4-b]pyrazine (5,7-dibromo-2,3-dichlorothieno[3,4-b]pyrazine).

4-2. Preparation of P-4 polymer polymer

[Scheme 4-2]

Compound 2,5-bis(2-ethylhexyl)-3,6-bis(5-(trimethylstenyl)thiophen-2-yl)-2,5-dihydropyrrole[3,4-c]pyrrolo -1,4-dione (2,5-bis(2-ethylhexyl)-3,6-bis(5-(trimethylstannyl)thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole -1,4-dione) 58.6 mg (0.068 mmol), 5,7-dibromo-2,3-dichloro[3,4-b]pyrazine (5,7-dibromo-2,3-dichlorothieno[3, 4- _b ] pyrazine) 25 mg ( _0.068 mmol) and 3.15 mg (5 mol%) and ligand tri(o-tolyl)phosphine (P(o-tol) ₃ , Tri(o-tolyl)phosphine) 2.43 mg (10 mol%) were put into a reaction tube in a glovebox and the stopper was closed. 0.4 mL of anhydrous chlorobenzene (CB) was injected using a syringe, and the solvent was purged in an argon atmosphere for 10 minutes, followed by reaction in a reactor at 105° C. for 2 hours. After precipitating the reaction solution in 50 mL of methanol, the precipitated solid is recovered through a filter. The recovered precipitate was filtered through a Soxhlet thimble, followed by Soxhlet extraction with methanol, acetone, hexane, methylene chloride, and chloroform solvents. The chloroform Soxhlet-extracted solution was concentrated, precipitated in methanol, and dried to obtain a high-molecular weight polymer. The polymer yield = 27%, 14 mg.

< Experimental example 1> Optical-electrical characterization

The optical-electrical properties of the material according to the embodiment of the present invention were analyzed, and the results are shown in Table 1 below.

In order to confirm the light absorption characteristics and electrochemical characteristics of the prepared organic semiconductor compound, the light absorption spectrum was measured and shown in FIG. 1, and the maximum absorption wavelength (λmax) and λedge are shown in Table 1. In addition, the HOMO and LUMO levels of the prepared organic semiconductor compounds were measured by cyclic voltammetry. The ferrocene/ferrocenium redox system (-4.8 eV) was measured and performed in the solid film state as a reference, and the results are shown in Table 1.

Example λmax [nm] Optical band gap [eV] Energy level [eV] Solution Film HOMO LUMO One 710 750 1.68 -5.30 -3.60 2 630 656, 706 1.44 -5.02 -3.97 3 656 737, 812 1.33 -5.42 -4.09 4 1200 1400 0.88 -5.50 -4.62

It can be seen that the compound according to the present invention has an excellent absorption rate in the near infrared region.

In the case of materials introduced with TPz, long-wavelength absorption is possible through strong molecular interactions, and the absorption wavelength shifts to long-wavelengths on the film due to its high crystallinity. In particular, in the case of P-4 with the introduction of the DPP unit, it can be seen that the band gap decreases to less than 1 eV and the absorption wavelength increases to 1400 nm in the film due to strong planarity induction.

< Experimental Example 2> Analysis of solar cell characteristics

The solar cell characteristics of the material according to the embodiment of the present invention were analyzed, and the results are shown in Table 2 below.

An organic substrate coated with ITO (Indium Tin Oxide), a transparent electrode (first electrode), is immersed in deionized water containing a cleaning solution, washed in an ultrasonic cleaner for 15 minutes, and washed three times each with deionized water, acetone, and IPA. After that, it was dried in an oven at 130° C. for 5 hours. The ITO glass substrate washed as described above was subjected to UV/ozone treatment for 15 minutes, and then ZnO·NPs having a thickness of 30 nm were spin-coated on the ITO substrate. Then, the substrate coated with ZnO NPs was heat treated at 100° C. for 10 minutes on a hot plate. A 0.4 wt% poly(ethyleneimine)-ethoxylated (PEIE) solution was applied on the ZnO·NPs layer by spin coating to a thickness of 3 nm.

Then, the device was transferred to a glove box filled with argon to apply the photoactive layer. The photoactive layer was prepared by combining Examples or Comparative Examples, which are the polymers of the present invention described in Tables 1 to 3 above, in a weight ratio of Y6 at a ratio of 1: 1.2, dissolved in a xylene solvent to prepare a solution, and a 0.45 μm (PTFE) syringe filter An organic semiconductor solution filtered through a syringe filter was coated on the PEIE layer to a thickness of 100 nm through a spin coating method.

The obtained device structure was deposited on the photoactive layer in a thermal evaporator under a vacuum of 3 X 10-6 torr, with MoO3 having a thickness of 10 nm and an Ag electrode having a thickness of 100 nm as the uppermost electrode, thereby completing an organic solar cell.

The open circuit voltage (Voc), short circuit current (Jsc), FF (Fill Factor), and PCE (Power Conversion Efficiency), which are electrical characteristics of each fabricated organic solar cell, are shown in Table 4 below.

The photovoltaic cell current density-voltage (J-V) characteristics of each of the organic solar cells prepared by the above method were measured using a Newport 1000W solar simulator under illumination simulating sunlight at 100 mW/cm 2 (AM 1.5 G). Electrical data were recorded using a Keithley 236 source-measure unit, and all characteristics were performed under room temperature atmospheric conditions. PV measurements Inc. was calibrated by a standard Si photodiode detector of . Incident photon-to-current conversion efficiency (IPCE) was measured as a function of wavelength in the range of 300 to 1000 nm (PV measurement Inc.) equipped with a xenon lamp as a light source and calibrated using a silicon standard photodiode. The thickness of the thin film was measured with a KLA Tencor Alpha-step IQ surface profilometer with an accuracy of ± 1 nm.

The results are summarized in Table 2 below. That is, the photovoltaic parameters of open circuit voltage (Voc), short-circuit current density (JSC), fill factor (FF), and power conversion efficiency (PCE) ) were arranged to do so. Among the photoelectric parameters, the fill factor and photoelectric conversion efficiency were calculated using the following formulas 1 and 2.

[Equation 1]

Fill Factor = (Vmp×Imp)/(Voc×JSC)

(In Equation 1 above, Vmp is the voltage value at the maximum power point, Imp is the current density, Voc is the open circuit voltage, and JSC is the short circuit current density.)

[Equation 2]

Photoelectric Conversion Efficiency = (Fill Factor) × (JSC × Voc)/100

(In Equation 2 above, JSC is the short-circuit current density, and Voc is the open-circuit voltage.)

Example electron donor: electron acceptor Voc [V] Jsc [mA/cm ² ] FF [%] PCE [%] One P-1: Y6 0.73 8.81 33.56 2.10 2 P-2: Y6 0.3 11.53 38.48 1.34 3 P-3: Y6 0.51 7.44 34 1.01 4

It can be confirmed that the compound according to the present invention not only has an excellent absorption rate in the near-infrared region, but also has excellent characteristics as an organic solar cell. and P-1, in which thiophene-substituted BDT (benzodithiophene) was introduced, showed the highest open-circuit voltage. As the highest current density is observed at P-2, it can be confirmed that TPz itself has excellent charge transfer characteristics. In the case of P-4, the band gap was reduced due to the strong planarity due to DPP, and the charge separation was not smooth due to the mismatch between the applied Y6 and the band gap, so the characteristics could not be observed.

Claims (12)

An infrared ray absorbing polymer compound containing a repeating unit represented by Formula 1 below:
[Formula 1]

In Formula 1,
A is not present or is any one selected from Formulas 2 to 4 below,
R ¹ to R ⁴ are each independently hydrogen, halogen or C1-C30 alkyl;
[Formula 2]

[Formula 3]

[Formula 4]

here,
R ^5a , R ^5b , R ^6a , R ^6b , R ^7a , and R ^7b are each independently
hydrogen, C1-C30 alkyl or halogen.
According to claim 1,
A does not exist,
R ¹ to R ⁴ are each independently a C1-C30 alkyl, a polymeric compound.
According to claim 1,
A is Formula 2,
R ¹ to R ⁴ are each independently C1-C30 alkyl;
^R5a and ^R5b are each independently a halogen, a high molecular compound.
According to claim 1,
A is Formula 3,
R ¹ to R ² are each independently C1-C30 alkyl;
R ³ to R ⁴ are each independently hydrogen;
R ^6a and R ^6b are each independently a C1-C30 alkyl, a polymeric compound.
According to claim 1,
A is Formula 4,
R ¹ to R ² are each independently halogen;
R ³ to R ⁴ are each independently hydrogen;
R ^7a and R ^7b are each independently a C1-C30 alkyl, a polymeric compound.
According to claim 1,
Formula 1 above,
A polymeric compound selected from the following formula:

,

,

,

.
According to claim 1,
The polymer compound has a weight average molecular weight of 1,000 to 200,000, the polymer compound.
An infrared-sensitive organic photoactive layer comprising the polymer compound of claim 1 as a donor material.
An infrared-sensitive organic photoelectric conversion device comprising the organic photoactive layer of claim 7.
An infrared-sensitive organic solar cell comprising the organic photoactive layer of claim 7.
A method for producing the polymer compound of claim 1, comprising polymerization of a monomer represented by Formula 1A and a monomer represented by Formula 1C:
[Formula 1A]

[Formula 1C] X ² -AX ²
wherein X ¹ is halogen, X2 is -SnMe ₃ ,
A, R ¹ to R ⁴ are as defined in claim 1.
Provided is a method for preparing the polymer compound according to claim 1, comprising polymerization of a monomer represented by Formula 1D and a monomer represented by Formula 1E.

[Formula 1D]

[Formula 1E]

wherein X ³ is halogen, X ⁴ is -SnMe ₃ ,
R ¹ to R ⁴ are as defined in claim 1,
Preferably, A may be of Formula 4.

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