KR101447281B1 - Polythiophene Composition and Method for Preparing Organic Solar Cell Including the Same - Google Patents

Abstract

The present invention provides a thiophene polymer composition comprising: hydrophobic thiophene polymers; fullerene derivatives; and amphiphilic thiophene double block copolymers including hydrophobic thiophene polymer blocks and hydrophilic thiophene polymer blocks. The thiophene polymer composition including amphiphilic thiophene double block according to the present invention is able to increase the crystallization of hole acceptors by generating the packing effects of side chains of thiophene polymers and is able to improve the performance of an organic electronic device by being included in a photoactive layer of the organic electronic device.

Description

TECHNICAL FIELD [0001] The present invention relates to a thiophene polymer composition and an organic solar cell including the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thiophene polymer composition and a method for producing an organic solar cell including the same, and more particularly, to a thiophene polymer composition for inducing self-assembly and increasing the degree of crystallization, .

Over the past 25 years, organic semiconducting materials using monomolecular and polymeric materials have been making remarkable progress. Semiconductor materials using existing inorganic materials have excellent characteristics and reliability, but they are gradually transferring their role to the organic semiconductor material due to the disadvantage of high cost of the manufacturing process and extreme conditions such as high temperature. Organic semiconductor materials are easier to manufacture than inorganic semiconductor materials because they are simple to manufacture and can be manufactured at low cost in the fabrication of devices. Due to the nature of organic materials, it is easy to develop materials that exhibit superior characteristics through simple structure modification .

(3-hexylthiophene) is a two-dimensional layered structure that is easy to self-assemble and has a charge carrier mobility of up to 0.1 cm ² V ^- 1 in an organic field effect transistor (OFET) ¹ S ^-1 It shows the measured result. Despite the recent discovery of a variety of high-efficiency alternating copolymers of electron-rich and electron-deficient units, P3HT is one of the most popular and attractive conductive polymers capable of studying the basic principles and mechanisms of organic solar cells (OPVs).

The bulk heterojunction (BHJ) architecture of organic solar cells (OPVs) consists of an electron donor-electron acceptor system blended in a double continuous phase, and the fullerene derivative (A: acceptor) and P3HT (D: donor) to form a three-dimensional percolated matrix at the nanoscale size. In bulk heterojunction (BHJ), the exciton is produced by the light absorption of P3HT and diffuses to the interface of a fullerene derivative (A: acceptor) with limited exciton diffusion length (~ 10 nm) and P3HT (D: donor) Charge transfer occurs.

When an exciton meets an electron acceptor at the interface, the diffused excitons begin to dissociate and lead to charge separation. The separated free carriers (electrons and holes) move to the respective electrodes (cathode and anode) and collection occurs. This procedure leads to the operation of external circuitry and solar devices.

However, the hole mobility (~ 10 ^-6 cm ² V ^-1 S ^-1 ) of P3HT in the above blend system is much lower compared to itself. The shape of the active layer of the bulk heterojunction (BHJ) thin film must be optimized to improve hole mobility. Examples include thermal annealing, solvent annealing, heat treatment under an electric field, and microwave annealing. This method provides an electron donor matrix and an electron acceptor domain that continuously penetrate while increasing the degree of crystallization of P3HT, resulting in an increase in charge transfer characteristics and an increase in current density.

Korean Patent Laid-Open No. 10-2010-0062855 discloses a fullerene derivative and an organic solar cell comprising the same. P3HT is used as an electron-donating polymer of an organic solar cell, and PCBM is used as an electron acceptor. However, .

Korean Patent Publication No. 10-2010-0062855

The present invention has been made to solve the above problems, and it is an object of the present invention to provide a thiophene polymer composition having an increased degree of crystallization of an electron donor and having excellent charge transport properties.

INDUSTRIAL APPLICABILITY The present invention can provide an organic electronic device in which current density is increased to improve electronic device characteristics.

According to one aspect of the present invention, a hydrophobic thiophene polymer; Fullerene derivatives; And an amphiphilic thiophene diblock copolymer comprising a hydrophobic thiophene polymer block and a hydrophilic thiophene polymer block.

The hydrophobic thiophene polymer may be composed of a repeating unit represented by the following structural formula (1).

[Structural formula 1]

In the above structural formula 1, R ¹ is a C1 to C20 alkyl group.

The fullerene derivative may be represented by the following structural formula (2).

[Structural formula 2]

In the structural formula 2, A is a C60, C70, C72, C76, C78, C84, or fullerene C90, R ² is a hydrogen atom or a C1 to C10 alkoxy group, R ³ is a hydrogen atom or a C1 to C10 alkyl group, m is an integer of 1 to 5, and n is an integer of 0 to 6.

The amphiphilic thiophene diblock copolymer can be represented by the following structural formula (3).

 [Structural Formula 3]

B-D

In the above structural formula 3, B is a hydrophobic thiophene polymer block composed of repeating units represented by the following structural formula 1,

[Structural formula 1]

Wherein R ¹ is a C ¹ to C 20 alkyl group and D is a hydrophilic thiophene polymer block comprising a repeating unit represented by the following structural formula 4,

[Structural Formula 4]

R ⁴ is a hydrogen atom or a C 1 to C 10 alkyl group, q is an integer of 1 to 8, and r is an integer of 1 to 10.

The amphiphilic thiophene diblock copolymer may have a molar ratio of the repeating units of the hydrophobic thiophene polymer block to the repeating units of the hydrophilic thiophene polymer block of from 1:99 to 99: 1.

Wherein the thiophene polymer composition has a content ratio of the hydrophobic thiophene polymer and the fullerene derivative of 5:95 to 95: 5, and the content of the amphiphilic thiophene diblock copolymer is such that the total amount of the hydrophobic thiophene polymer and the fullerene derivative May be 0.1 to 20 parts by weight based on 100 parts by weight of the composition.

The hydrophobic thiophene polymer may have a number average molecular weight of from 5,000 to 500,000.

The amphiphilic thiophene diblock copolymer may have a number average molecular weight of from 5,000 to 1,000,000.

The amphiphilic thiophene diblock copolymer may have a molecular weight distribution between 1 and 1.5.

The amphiphilic thiophene diblock copolymer can be self-assembled.

The hydrophobic thiophene polymer may be self-assembled.

The amphiphilic thiophene diblock copolymer can increase the crystallinity of the hydrophobic thiophene polymer.

The hydrophobic thiophene polymer may be a 3-hexylthiophene (3-hexylthiophene).

The fullerene derivative may be 6,6-phenyl-C61-butyl acid methyl ester (PC61BM).

The amphiphilic thiophene diblock copolymer can be prepared by reacting ((3-hexylthiophene) -b- (2- (2- {2- [2- (2-methoxy-ethoxy) (2-methoxy-ethoxy) -ethoxy] -ethoxy} -ethyl) thiophene) ).

According to another aspect of the present invention, there is provided an organic electronic device comprising the thiophene polymer composition.

The organic electronic device may be one selected from the group consisting of an organic light emitting device, an organic solar cell, an organic photoconductor (OPC), an organic memory, and an organic transistor.

According to another aspect of the present invention, An organic active layer located on the first electrode and comprising a thiophene polymer composition; And a second electrode located on the organic active layer, wherein the thiophene polymer composition comprises a hydrophobic thiophene polymer; Fullerene derivatives; And an amphiphilic thiophene diblock copolymer comprising a hydrophobic thiophene polymer block and a hydrophilic thiophene polymer block.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a first electrode; Forming an organic active layer comprising a thiophene polymer composition on the first electrode; And forming a second electrode on the organic active layer.

The thiophene polymer compositions comprising an amphiphilic thiophene diblock copolymer according to the present invention can increase the crystallinity of the hole acceptor by creating the packing effect of the side chain of the thiophene polymer.

The thiophene polymer composition of the present invention can be included in the photoactive layer of the organic electronic device to improve the performance of the organic electronic device.

Fig. 1 shows the results of absorption spectrum analysis of the composition according to Example 3 of the present invention.
2 shows the XRD analysis results of the composition according to Example 3 of the present invention.
3 is a photograph showing the contact angle of the composition according to Example 3 of the present invention.
4 is a photograph of AFM measurement of the composition according to Example 3 of the present invention.
5 is an analysis of JV characteristics of the composition according to Example 3 of the present invention.

The invention is capable of various modifications and may have various embodiments, and particular embodiments are exemplified and will be described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific 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 terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of 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.

In order to accomplish the above object, the present invention provides a thiophene polymer composition comprising: a hydrophobic thiophene polymer; Fullerene derivatives; And an amphiphilic thiophene diblock copolymer comprising a hydrophobic thiophene polymer block and a hydrophilic thiophene polymer block.

The hydrophobic thiophene polymer may be composed of a repeating unit represented by the following structural formula (1).

[Structural formula 1]

In the above structural formula 1, R ¹ is a C1 to C20 alkyl group.

The fullerene derivative may be represented by the following structural formula (2).

[Structural formula 2]

In the structural formula 2, A is a C60, C70, C72, C76, C78, C84, or fullerene C90, R ² is a hydrogen atom or a C1 to C10 alkoxy group, R ³ is a hydrogen atom or a C1 to C10 alkyl group, m is an integer of 1 to 5, and n is an integer of 0 to 6.

The amphiphilic thiophene diblock copolymer can be represented by the following structural formula (3).

 [Structural Formula 3]

B-D

In the above structural formula 3, B is a hydrophobic thiophene polymer block composed of repeating units represented by the following structural formula 1,

[Structural formula 1]

Wherein R ¹ is a C ¹ to C 20 alkyl group and D is a hydrophilic thiophene polymer block comprising a repeating unit represented by the following structural formula 4,

[Structural Formula 4]

R ⁴ is a hydrogen atom or a C 1 to C 10 alkyl group, q is an integer of 1 to 8, and r is an integer of 1 to 10.

The amphiphilic thiophene diblock copolymer may have a molar ratio of the repeating units of the hydrophobic thiophene polymer block to the repeating units of the hydrophilic thiophene polymer block of from 1:99 to 99: 1. The molar ratio of the repeating unit of the hydrophobic thiophene polymer block to the repeating unit of the hydrophilic thiophene polymer block can be variously adjusted to improve the characteristics of the electronic device according to the content of the other composition components of the composition.

The thiophene polymer composition may have a content ratio of the hydrophobic thiophene polymer and the fullerene derivative of 5:95 to 95: 5, and the content ratio of the thiophene polymer composition may be varied depending on the characteristics of the desired electronic device.

The content of the amphiphilic thiophene diblock copolymer is 0.1 to 20 parts by weight, preferably 1 to 20 parts by weight, based on 100 parts by weight of the total content (A + B) of the hydrophobic thiophene polymer (A) and the fullerene derivative (B) To 15 parts by weight, and more preferably from 3 to 10 parts by weight. When the content of the amphiphilic thiophene diblock copolymer is less than 0.1 part by weight based on 100 parts by weight of the total content (A + B) of the hydrophobic thiophene polymer (A) and the fullerene derivative (B) The improvement of the degree of crystallinity of the opene polymer may be insignificant. If it exceeds 20 parts by weight, the characteristics of the electronic device may be deteriorated.

The hydrophobic thiophene polymer may have a number average molecular weight of 5,000 to 500,000, preferably 10,000 to 100,000.

The amphiphilic thiophene diblock copolymer may have a number average molecular weight of 5,000 to 1,000,000, preferably 10,000 to 500,000, more preferably 10,000 to 200,000.

The amphiphilic thiophene diblock copolymer may have a molecular weight distribution between 1 and 1.5.

The amphiphilic thiophene diblock copolymer can be self-assembled.

The hydrophobic thiophene polymer may be self-assembled.

The amphiphilic thiophene diblock copolymer can increase the crystallinity of the hydrophobic thiophene polymer in the thiophene polymer composition.

The hydrophobic thiophene polymer may be a 3-hexylthiophene (3-hexylthiophene).

Referring to FIG. 1, Regioregular P3HT has a hexyl side chain at position 3 of the thiophen unit, and the hexyl side chain can induce self assembly, and furthermore, the pp stacking of the thiophen unit . The hexyl side chains leading to self-assembly can be promoted by intermolecular interactions introduced solvophobically, which can be induced by p-conjugated block copolymers with hydrophobic and hydrophilic chains, and in the solid state A higher level of the layered structure can be formed.

The fullerene derivative may be 6,6-phenyl-C61-butyl acid methyl ester (PC61BM).

The amphiphilic thiophene diblock copolymer can be prepared by reacting ((3-hexylthiophene) -b- (2- (2- {2- [2- (2-methoxy-ethoxy) (2-methoxy-ethoxy) -ethoxy] -ethoxy} -ethyl) thiophene) ).

According to another aspect of the present invention, there is provided an organic electronic device comprising the thiophene polymer composition.

The organic electronic device may be one selected from the group consisting of an organic light emitting device, an organic solar cell, an organic photoconductor (OPC), an organic memory, and an organic transistor.

According to another aspect of the present invention, there is provided a plasma display panel comprising: a first electrode; An organic active layer located on the first electrode and comprising a thiophene polymer composition; And a second electrode located on the organic active layer, wherein the thiophen polymer composition comprises a hydrophobic thiophene polymer; Fullerene derivatives; And an amphiphilic thiophene diblock copolymer comprising a hydrophobic thiophene polymer block and a hydrophilic thiophene polymer block.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a first electrode; Forming an organic active layer comprising a thiophene polymer composition on the first electrode; And forming a second electrode on the organic active layer.

Hereinafter, the present invention will be described more specifically by way of examples. However, this is for illustrative purposes only, and thus the scope of the present invention is not limited thereto.

[Example]

The fullerene derivative [6,6] -Phenyl-C ₆₁ butyric acid methyl ester (PC ₆₁ BM) was purchased from Nano-C.

PEDOT: PSS (poly (3,4-ethylene dioxythiophene): poly (styrene sulfonate)) was purchased from Bayer AG (Grade: PEDOT P VP AI 4083).

All other reagents were purchased from Aldrich Chemical Co. and used without purification.

Manufacturing example  One : Thiophene  polymer P3HT ( M _w  = 29 kDa )

[Reaction Scheme 1]

Referring to Scheme 1, 2 mmol of 2-bromo-3-hexyl-5-iodothiophene was added to a 50 ml single-necked flask and 20 ml of lithium chloride (anhydrous lithium chloride) and anhydrous tetrahydrofuran (THF) 1 mmol (2 mmol) of isopropyl magnesium chloride is added and the mixture is stirred at room temperature. After 1 hour, Ni (dppp) Cl ₂ (0.01-0.05 mmol) catalyst is dispersed in THF (20 ml), placed in the flask under reaction, and the mixture is stirred for 12 hours.

All procedures proceed in glove box with N ₂ status. The reaction is terminated by the addition of 5 M aqueous HCl solution and extracted three times with chloroform. Water is removed from the organic solvent layer with magnesium sulfate (MgSO ₄ ) and the solvent is concentrated using a vacuum evaporator. The concentrate is extracted with methanol and filtered. After the reaction, the polymer was dried in a vacuum oven at room temperature for 24 hours to obtain a purple solid (P3HT). Yield 68.9%.

^{1 H-NMR (300 MHz,} CDCl 3, ppm): δ 6.98 (s, 1H); 2.81 (t, J = 7.5 Hz, 2H); 1.71 (br, 2 H); 1.36 (br, 6 H); 0.91 (t, J = 6.6 Hz, 3 H).

P3HT (M _w = 45 kDa) was purchased from Rieke Metal Inc. (4002-E grade).

Manufacturing example  2 : Amphipathic Thiophene  Double block copolymer ( BP93 )

[Reaction Scheme 2]

2-Bromo-3-hexyl-5-iodothiophene (187 mg, 0.500 mmol), lithium chloride (21.2 mg, 0.500 mmol) and anhydrous THF (5 ml) were added to a 50 ml single- , 0.250 mL (0.0500 mmol) of isopropyl magnesium chloride in THF dissolved in THF at a concentration of 2 M was added, and the reaction solution was stirred at room temperature for 1 hour to prepare solution A. To another flask was added 2-bromo-3- (3,6,9,12-tetraoxatridecanyl) thiophene (719 mg, 1.50 mmol) and 0.750 Ml (1.50 mmol) of isopropyl magnesium chloride dissolved in THF A, the solution B is prepared.

The Ni (dppp) Cl ₂ catalyst (10.8mg, 0.02mmol) was dispersed in THF (20mL) was added to solution A and the mixture was stirred for 1 hour. Referring to Reaction Scheme 2, Solution A and Solution B, which were prepared so that the ratio of Compound 1 and Compound 4 was 75:25 mol%, were added using a syringe and stirred for 12 hours to obtain a mixture of Compound 1 and Compound 4 in a molar ratio of 93: Was prepared.

All processes proceed in glove box with N ₂ status. The reaction is terminated by the addition of 5 M aqueous HCl solution and extracted three times with chloroform. The organic solvent layer is washed with MgSO ₄ and the solvent is concentrated using a vacuum evaporator. The concentrate is extracted with methanol and cold hexane.

¹ H-NMR (300 MHz, CDCl ₃ , ppm): (based on integral of proton at 4-position of P3HT block = 1)? 7.07 (s, 0.08H); 6.98 (s, 1 H); 3.67 (br, 0.86H); 3.54 (br, 0.16H); 3.35 (br, 0.25H); 3.10 (br, 0.09H); 2.81 (t, J = 7.5 Hz, 2H); 1.71 (br, 2 H); 1.36 (br, 6 H); 0.91 (t, J = 6.6 Hz, 3 H).

Manufacturing example  3: Amphipathic Thiophene  Double block copolymer ( BP73 )

Referring to Reaction Scheme 2, Solution A and Solution B were added using a syringe so that Compound 1 and Compound 4 were in a ratio of 50:50 mol% instead of 75:25 mol% , A copolymer having a molar ratio of Compound 1 to Compound 4 of 73:27 was prepared in the same manner as in Production Example 2. [

¹ H-NMR (300 MHz, CDCl ₃ , ppm): (based on integral of proton at 4-position of P3HT block = 1)? 7.07 (s, 0.32H); 6.98 (s, 1 H); 3.67 (br, 4.00H); 3.54 (br, 0.83H); 3.35 (br, 1. 17H); 3.10 (br, 0.57H); 2.81 (t, J = 7.5 Hz, 2H); 1.71 (br, 2 H); 1.36 (br, 6 H); 0.91 (t, J = 6.6 Hz, 3 H).

Manufacturing example  4 : Amphipathic Thiophene  Double block copolymer ( BP26 )

Referring to Reaction Scheme 2, Solution A and Solution B, which were prepared so that the ratio of Compound 1 and Compound 4 was 25:75 mol%, instead of the ratio of Compound 1 and Compound 4 being 75:25 mol%, were mixed using a syringe A copolymer having a molar ratio of Compound 1 to Compound 4 of 26:74 was prepared in the same manner as in Production Example 2. [

¹ H-NMR (300 MHz, CDCl ₃ , ppm): (based on integral of proton at 4-position of P3HT block = 1)? 7.07 (br, 3.07H); 6.98 (br, 1 H); 3.67 (br, 37.96H); 3.54 (br, 7.54H); 3.35 (br, 9.83H); 3.10 (br, 5.687H); 2.81 (t, J = 7.5 Hz, 2H); 1.71 (br, 2 H); 1.36 (br, 6 H); 0.91 (t, J = 6.6 Hz, 3 H).

Example  One

In a glove box filled with nitrogen gas, 66 parts by weight of P3HT, 34 parts by weight of PC61BM and 5 parts by weight of BP93 were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Example  2

In a glove box filled with nitrogen gas, 50 parts by weight of P3HT, 50 parts by weight of PC61BM and 5 parts by weight of BP93 were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Example  3

In a glove box filled with nitrogen gas, 34 parts by weight of P3HT, 66 parts by weight of PC61BM and 5 parts by weight of BP93 were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Example  4

In a glove box filled with nitrogen gas, 20 parts by weight of P3HT, 80 parts by weight of PC61BM and 5 parts by weight of BP93 were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Example  5

A composition solution was prepared in the same manner as in Example 2 except that BP73 was used instead of BP93.

Example  6

A composition solution was prepared in the same manner as in Example 2 except that BP26 was used instead of BP93.

Comparative Example  One

In a glove box filled with nitrogen gas, 66 parts by weight of P3HT and 34 parts by weight of PC61BM were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Comparative Example  2

In a glove box filled with nitrogen gas, 50 parts by weight of P3HT and 50 parts by weight of PC61BM were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Comparative Example  3

In a glove box filled with nitrogen gas, 34 parts by weight of P3HT and 66 parts by weight of PC61BM were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Comparative Example  4

In a glove box filled with nitrogen gas, 20 parts by weight of P3HT and 80 parts by weight of PC61BM were dissolved in 100 parts by weight of o-dichlorobenzene for 10 hours to prepare a composition solution.

Device Example  One

The organic solar cell is composed of an ITO / PEDOT: PEDOT glass substrate having an Indium Tin Oxide (ITO) glass substrate coated with aluminum as a cathode and poly (3,4-ethylene dioxythiophene) PSS / Polymer: PC61BM / Ca / Al architecture was used. Commercially available patterned ITO is washed with 2-propanol, acetone and ethanol. The ITO substrate is flushed with N ₂ gas for drying. Next, after the UV-ozone treatment for improving the hydrophilicity of the layer, a 30 nm layer of PEDOT: PSS was spin-coated. The device then moves to a glove box filled with N ₂ for active layer deposition. The composition solution prepared in Example 1 was spin-coated to form an active layer having a thickness of ~ 140 nm. The upper electrode (Ca / Al, 3 nm / 100 nm) was deposited by shadow mask and thermal evaporation at 7.0 × 10 ^-7 Torr.

Device Example  2

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 2 was used instead of the composition solution prepared in Example 1,

Device Example  3

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 1 was used instead of the composition solution prepared in Example 1 to spin-coat the same.

Device Example  4

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 4 was used instead of the composition solution prepared in Example 1,

Device Example  5

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 5 was used instead of the composition solution prepared in Example 1.

Device Example  6

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 1 was used instead of the composition solution prepared in Example 1 to spin-coat the same.

Device comparison example  One

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 1 was used instead of the composition solution prepared in Comparative Example 1 to spin-coat the same.

Device comparison example  2

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 1 was used instead of the composition solution prepared in Comparative Example 2 to spin-coat the same.

Device comparison example  3

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Example 1 was used instead of the composition solution prepared in Comparative Example 3 to spin-coat the same.

Device comparison example  4

A solar cell was prepared in the same manner as in Example 1 except that the composition solution prepared in Comparative Example 4 was used instead of the composition solution prepared in Example 1.

Test Example

UV - Vis absorption spectra  Measure

The UV-VIS absorption spectrum of the composition was measured with a Mecasys Optizen Pop UV / Vis spectrophotometer and measured to investigate the effect of BP93. The presence or absence of BP93 and the UV-VIS absorption spectrum of the P3HT: PC61BM composition are shown in Fig. One of the two distinct peaks is the absorption peak by PC61BM around 335nm. The other peak is a broad peak consisting of absorption at 510 nm and absorption of two vibration regions of 550 nm and 600 nm attributed to P3HT. The peak in the region of 550 nm is determined by the absorption of the extended conjugation of P3HT in the thin film and the other of 600 nm is known to be provided in stacking between chains of P3HT. Overall absorptions are very similar, but the ~ 600nm region clearly shows that the addition of BP93 enhances the interchain stacking of P3HT.

X-ray diffraction  ( GIXRD )Measure

X-ray diffraction (GIXRD) of the composition was measured using a Rigaku X-ray diffractometer (D / MAX-2500) and is shown in FIG.

According to Fig. 2, it can be seen from the x-ray diffraction that the self-assembly of P3HT is improved in the mixture after addition of BP93. At around 2θ = 5.3 ^o , corresponding to the interlaminar spacing and lamellar structure formed by parallel stacking of P3HT main structures separated by hexyl side chains Shows an intense diffraction peak 100. The P3HT: PC61BM mixture with 5 wt% BP93 added packing effect of hydrophobic hexyl and hydrophilic ethylene glycol oligomer side chains, resulting in increased P3HT crystallinity and increased strength.

Contact angle ( contact angle ) Measure

The contact angle was measured using a goniometry method (DSA-10T, KRUSS GmbH). The surface energy (γs) can be calculated from the contact angle using Owens-Wendt geometric mean, using different known solutions (deionized water and glycerol). The surface energy (? S) of PC61BM measured from the contact angle of water and glycerol is shown in Fig. 3 at 43.5 mN / m. On the other hand, the γs of BP93 is 33.5 mN / m, slightly larger than P3HT (30.3 mN / m). This fact indicates that the hydrophilic block of BP93 has a more affinity for the hydrophilic PC61BM and the hydrophilic P3EGT block exists at the interface between the P3HT crystal domain and the PC61BM cluster and the effective contact between the P3HT crystal domain and the PC61BM cluster I suggest.

Atomic Force Microscope ( AFM , Atomic Force Microscope ) Image measurement

The surface morphology was scanned with an Atomic Force Microscope of the VEECO Dimension 3100 with a Nanoscope V (ver. 7.0). The AFM (Atomic Force Microscope) height image with or without addition of BP 93 after heat treatment at 150 ^° C for 15 min is shown in FIG. In the P3HT: PC61BM composition film, the surface is very flat with 0.69 nm rms roughness. On the other hand, the rms value increased to 1.03 nm due to the addition of BP93 to the P3HT: PC61BM mixture. The change in rms suggests that BP93 promotes self-assembly of the P3HT hexylside chain and increases the crystal domain in the P3HT: PC61BM composition.

Hole mobility measurement

Hole mobility of the composition was measured on a pre-patterned ITO substrate. The ITO substrate was washed with 2-propanol, acetone, ethanol and 2-propanol, and UV-ozone treatment was applied for 10 minutes. PEDOT: PSS (PEDOTP VP AI 4083, Bayer AG) was spin-coated on the aqueous dispersion in a 30 nm thick layer. The coated substrate was then baked at < RTI ID = 0.0 > 150 C < / RTI > After baking, a solution of the polymer of dichlorobenzene was spin-cast onto a PEDOT: PSS layer of ~ 70 nm thickness, and the sample was dried in a crushed petri dish for 30 minutes. The Au electrode is deposited by thermal evaporation under a vacuum of 10 ^-6 Torr. The space charge-limited current (SCLC) method obtains the hole mobility of the material. The SCLS mobility is driven by the Mott-Gurney criterion.

J = 9 ε ₀ ε _r m _h V ² / 8L ³

J is the current density, L is the film thickness of the active layer, m _h is the hole mobility,? _R is the relative permittivity constant of the transport medium,? ₀ is the dielectric constant of free space, V is the device internal voltage, V = V _appl - V _bi , V _appl is the applied voltage, V _r is the voltage drop due to series resistance and contact resistance at the electrode, and V _bi is the built - in voltage resulting from the difference in relative work function of the two electrodes. V _bi can be measured at the transition between the ohmic region and the SCLC region .

P3HT: BP93: hole transport thin film and the calculation of PC61BM was ^{1.13 × 10 -4 cm 2 / (} Vs), This is larger than the P3HT: PC61BM thin film (μ _h = 1.49 × 10 ^-5 cm ² / (Vs)). The increased hole mobility is analyzed to be due to the improved crystallinity of the P3HT: BP93 material.

Solar cell performance measurement

In order to confirm the relationship between the composition and the device performance, the performance of the bulk heterojunction solar cell manufactured according to the device example 1 and the device comparative example 2 was measured. The results are shown in FIG. 5, The results are summarized as follows. The amorphous thiophene diblock copolymer prepared in Preparation Example 2 was prepared by changing the content of P3HT, which is a hole acceptor, and the electron acceptor PCBM, in the composition.

The AM 1.5 solar simulator (Newport, M-91190A, with a 450 W xenon lamp) under the illumination of the AM 1.5 G solar light simulation. A solar cell measurement of OPVs was performed using a computer-controlled Keithley 2400 digital source meter . Power was reduced by using a reference Si photodiode mounted with a color matching filter (KG-3, SCHOTT) to reduce discrepancies to less than 4% in the region of 350-750 nm between the simulated light and the AM 1.5 G AM 1.5 G solar standard.

division Composition P3HT
(Parts by weight) PC61BM
(Parts by weight) Copolymer V _oc
[V] J _sc [mA / cm ² ] FF PCE
[%] Kinds Weight portion Device Embodiment 1 Example 1 66 34 BP93 5 0.65 10.1 0.54 3.5 Device Example 2 Example 2 50 50 BP93 5 0.63 11.1 0.57 3.9 Device Embodiment 3 Example 3 34 66 BP93 5 0.61 8.5 0.56 2.9 Device Example 4 Example 4 20 80 BP93 5 0.61 7.1 0.56 2.4 Element Embodiment 5 Example 5 50 50 BP73 5 0.61 7.9 0.55 2.6 Device Example 6 Example 6 50 50 BP26 5 0.62 7.8 0.42 2.0 Device Comparative Example 1 Comparative Example 1 66 34 - - 0.62 8.4 0.48 2.5 Device Comparative Example 2 Comparative Example 2 50 50 - - 0.63 8.3 0.58 3.1 Device Comparative Example 3 Comparative Example 3 34 66 - - 0.62 7.9 0.47 2.3 Device Comparative Example 4 Comparative Example 4 20 80 - - 0.62 7.8 0.42 2.0

As in the above table results, the J _sc of a bulk heterojunction device composed of P3HT: PC61BM (+ BP93) in Device Example 2 Value of 11.1 mA / cm < ² > , And the power conversion efficiency (PCE) value is increased to 3.9%.

In the case of P3HT: PC61BM (+ BP93) with excellent performance, the optimum value was obtained when P3HT: PC61BM was mixed with BP93 at 1: 1: 0.05.

Devices with bulk double junction structures can be further improved by replacing P3HT: PC61BM (+ BP93) instead of P3HT: PC61BM as a receptor, which results in improved interchain stacking of P3HT by addition of BP93 in the region of about 600 nm As well as the increase in demand.

Claims (19)

Hydrophobic thiophene polymers;
Fullerene derivatives; And
An amphiphilic thiophene diblock copolymer comprising a hydrophobic thiophene polymer block and a hydrophilic thiophene polymer block,
Wherein the hydrophobic thiophene polymer comprises a repeating unit represented by the following structural formula 1,
The fullerene derivative is represented by the following structural formula 2,
Wherein the amphiphilic thiophene diblock copolymer is represented by the following structural formula (3).
[Structural formula 1]

In the above formula 1,
R ¹ is a C1 to C20 alkyl group,
[Structural formula 2]

In the above formula 2,
A is fullerene of C60, C70, C72, C76, C78, C84, or C90,
R ² is a hydrogen atom or a C 1 to C 10 alkoxy group,
R ³ is a hydrogen atom or a C1 to C10 alkyl group,
m is an integer of 1 to 5,
n is an integer of 0 to 6,
[Structural Formula 3]
BD
In the above formula 3,
B is a hydrophobic thiophene polymer block composed of the repeating units represented by the structural formula 1,
D is a hydrophilic thiophene polymer block composed of a repeating unit represented by the following structural formula 4,
[Structural Formula 4]

In the above formula 4,
R ⁴ is a hydrogen atom or a C1 to C10 alkyl group,
q is an integer of 1 to 8,
r is an integer of 1 to 10; delete delete delete The method according to claim 1,
Wherein the amphiphilic thiophene diblock copolymer has a molar ratio of the repeating units of the hydrophobic thiophene polymer block to the repeating units of the hydrophilic thiophene polymer block of from 1:99 to 99: 1. The method according to claim 1,
The thiophene polymer composition comprises
Wherein the content of the hydrophobic thiophene polymer and the fullerene derivative is 5: 95 to 95: 5,
Wherein the amount of the amphiphilic thiophene diblock copolymer is 0.1 to 20 parts by weight based on 100 parts by weight of the total amount of the hydrophobic thiophene polymer and the fullerene derivative. The method according to claim 1,
Wherein the hydrophobic thiophene polymer has a number average molecular weight of from 5,000 to 500,000. The method according to claim 1,
Wherein the amphiphilic thiophene diblock copolymer has a number average molecular weight of from 5,000 to 1,000,000. The method according to claim 1,
Wherein the amphiphilic thiophene diblock copolymer has a molecular weight distribution of from 1 to 1.5. The method according to claim 1,
Wherein said amphiphilic thiophene diblock copolymer is self-assembled. ≪ RTI ID = 0.0 > 21. < / RTI > 11. The method of claim 10,
Wherein the hydrophobic thiophene polymer is self-assembled. 12. The method of claim 11,
Wherein the amphiphilic thiophene diblock copolymer increases the crystallinity of the hydrophobic thiophene polymer. The method according to claim 1,
Wherein the hydrophobic thiophene polymer is a 3-hexylthiophene. The method according to claim 1,
Wherein the fullerene derivative is 6,6-phenyl-C61-butyl acid methyl ester (PC61BM). The method according to claim 1,
The amphiphilic thiophene diblock copolymer can be prepared by reacting ((3-hexylthiophene) -b- (2- (2- {2- [2- (2-methoxy-ethoxy) (2-methoxy-ethoxy) -ethoxy] -ethoxy} -ethyl) thiophene) ). ≪ / RTI > An organic electronic device comprising the thiophene polymer composition according to claim 1. 17. The method of claim 16,
Wherein the organic electronic device is one selected from the group consisting of an organic light emitting device, an organic solar cell, an organic photoconductor (OPC), an organic memory, and an organic transistor. A first electrode;
An organic active layer located on the first electrode and comprising a thiophene polymer composition according to claim 1; And
A second electrode located on the organic active layer;
Including organic solar cells. Forming a first electrode;
Forming an organic active layer comprising a thiophene polymer composition according to claim 1 on a first electrode; And
Forming a second electrode on the organic active layer;
Wherein the organic photovoltaic cell is a photovoltaic cell.

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