KR20200093728A - Method of determining a charge transfer complex by electric conductivity - Google Patents

Abstract

The present invention relates to a method for calculating formation efficiency of a charge transfer complex from an organic semiconductor used for an organic electronic device to determine an efficient charge transfer complex. According to one embodiment of the present invention, the method for optically determining formation efficiency of a charge transfer complex in an organic semiconductor used for an organic electronic device may calculate the maximum formation efficiency of the charge transfer complex from a double layer that a second material layer is stacked on a first material layer from electrical conductivity.

Description

How to determine the formation efficiency of a charge transfer complex from electrical conductivity {METHOD OF DETERMINING A CHARGE TRANSFER COMPLEX BY ELECTRIC CONDUCTIVITY}

The present invention relates to a method for determining an optimal dopant doped in a host material of an electron transport layer or hole transport layer used in an organic electronic device from electrical conductivity characteristics.

An organic light emitting diode (LED) is a self-luminous display that excites and emits a fluorescent organic compound to emit light, so it can be driven at low voltage, easy to thin, and has a wide viewing angle and fast response speed to liquid crystal display devices. Therefore, it is attracting attention as a next-generation display capable of resolving the drawbacks indicated as problems.

The efficiency and useful life of an organic electronic device including a photoactive layer such as, for example, an organic light emitting diode (OLED), an organic solar cell, or an organic photodetector is particularly an electrode. It depends on how good charge carrier injection from the field to the photoactive layer or from the photoactive layer to the electrodes is.

The organic electronic device 100, as shown in Figure 1, the substrate 110, the first electrode 120, the semiconductor layer 130 for transporting electrons and holes on the first electrode 120 , A second electrode 150 on the light emitting layer 140 which is a photoactive layer on the semiconductor layer 130.

The semiconductor layer transports electrons or holes to the light emitting layer to recombine in the light emitting layer to form excitons, and emits light while the excitons transition to the ground state. Generally, in order to increase the efficiency of light emission, electrons or holes in the semiconductor layer Dopants are being added to increase transport capacity. In this case, a manufacturing process for deriving the optimal combination of the host material and the dopant is essential in that the efficiency of the light emitting layer can be greatly changed according to the type of dopant added to the host material constituting the electron or hole transport layer.

Organic semiconductor layer to improve the efficiency of the device in Korean Patent No. 10-1393176 (organic electronic device and its manufacturing method) and Korean Patent Publication No. 10-2011-0110172 (improvement of OLED stability through doped hole transport layer) An organic electronic device has been proposed to improve the efficiency by introducing an inorganic compound to and controlling the content of the optimized inorganic compound. However, in order to derive an optimized inorganic compound, each device is manufactured according to the inorganic compound in the organic semiconductor layer and the efficiency is measured to determine the inorganic compound. In this case, there is a hassle of manufacturing all the devices for each inorganic compound. In addition, it also has the problem of time and cost.

That is, a method of using an inorganic compound as a configuration of a charge carrier layer capable of performing a charge injection role into the light emitting layer 140 qualitatively, including the above-mentioned conventional technology, is proposed, and the light of the organic electronic device 100 is proposed. While proposing that the emission efficiency can be maximized, the inorganic compound is determined in any way in order to control the amount of charges supplied to the light-emitting layer 140, and the above-described light emission is performed when the crystal for the inorganic compound is performed in some way. It can be said that the electric conductivity of the organic electronic device 100 that can be driven with low power while improving efficiency is not clearly presented.

As a method for improving the transport capacity of electrons and holes, organic semiconductors and/or inorganic compounds, etc., are mixed as a dopant in a host material, and the optimal dopant is selected and determined according to the type of host material. It is a situation that cannot be determined without directly manufacturing electronic devices. Accordingly, there is a demand for a method of more easily determining a host material and a dopant without manufacturing an organic electronic device.

Registered Patent No. 10-1393176 (Organic electronic device and its manufacturing method) Korean Patent Publication No. 10-2011-0110172 (Improved OLED stability through doped hole transport layer)

The present invention has been proposed in order to solve the above problems and measures the electrical conductivity characteristics changed by the charge transfer phenomenon occurring at the interface with the inorganic compound and/or the organic semiconductor compound to measure the charge transfer complex (charge transfer). complex) We intend to provide a method to determine the optimal dopant by analyzing the formation efficiency.

More specifically, an object of the present invention is to determine an optimal charge transfer complex using a difference in electrical conductivity generated by the double layer by forming a double layer on which a charge transfer complex is formed by stacking a host material layer and a dopant layer.

In order to achieve this object, a method for determining an optimal charge transfer complex from electrical characteristics in view of the fact that a charge transfer complex is formed when a dopant is added to the host material of the electron or hole transport layer in the organic electronic device of the present invention The maximum charge transfer complex is formed from the double layer in which the second material layer is stacked on the first material layer, and the formation efficiency of the maximum charge transfer complex is formed from the double layer on which the second material layer is stacked on the first material layer. The efficiency is determined by determining an efficient charge transfer complex characterized by calculating the maximum efficiency from the electrical conductivity of the first material layer and the second material layer laminated on the first material layer to form a double layer. Doing.

The first material layer and the second material layer may be host materials or dopants of the electron transport layer and the hole transport layer.

The formation efficiency of the maximum charge transfer complex can be calculated by changing the thickness of the first material layer and the second material layer, and the thickness of the first material layer and the second material layer varies in a range of 1 to 50 nm. It may be.

It is characterized in that the maximum efficiency is calculated from the electrical conductivity of the first material layer and the second material layer is laminated on the first material layer to form the double layer formed electrical conductivity.

The step of forming the double-layered electrical conductivity includes a plurality of channels, and the plurality of channels each include at least two or more electrodes (s10);

Forming a first material layer between the two or more electrodes (s20);

Measuring current and voltage by applying current to the plurality of channels (s30);

Obtaining an electrical conductivity of the first material layer from the current and voltage measured from the plurality of channels (s40);

Forming a double layer by stacking a second material layer on the first material layer (s50);

Measuring a current and a voltage by applying a voltage to a plurality of channels on which the double layer is formed (s60); And

It is possible to determine an efficient charge transfer complex, including the step (s70) of obtaining electrical conductivity with a double layer formed from current and voltage measured from a plurality of channels on which the double layer is formed.

The electrical conductivity in which the first material layer and the double layer are formed may be obtained by a TLM (Trnasmission line method).

The length between the two or more electrodes can be varied in the range of 1 to 1000 μm.

The first material layer and the second material layer may be organic semiconductor compounds or inorganic compounds.

The organic semiconductor compound is TPD (N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[l,l-biphenyl]-4,4'diamine, N,N'-bis(3-methylphenyl )-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine), NPB(N,N'-di(l-naphthyl)-N,N'-diphenylbenzidine, N, N'-di(1-naphthyl)-N,N'-diphenylbenzene), TCTA(4,4',4"tris(N-carbazolyl)triphenylamine, 4,4',4"-tris (N- Carbazolyl) triphenylamine), Bphen (Bathophenanthroline), BCP (bathocuproine), rubrene`, hexadecafluorophthalocyanine (F16CuPc), 11,11,12,12-tetracyanonaphtho-2,6-qui Nodimethane (11,11,12,12-tetracyanonaphtho-2,6-quinodimethane, TNAP), 3,6-difluoro-2,5,7,7,8,8-hexacyano-quinodimethane ( 3,6-difluoro-2,5,7,7,8,8-hexacyano-quinodimethane (F2-HCNQ), Tetracyanoquinodimethane (TCNQ) and molybdenum tri(1,2-bis(trifluoro) Romethyl) ethane-1,2-dithioene (molybdenum tris [1,2-bis (trifluoromethyl)ethane-1,2-dithiolene, Mo (tfd) 3) may be one or more selected. The compound may be selected from one or more of ReO3, MoO3, CuI, V2O5, WO3, Fe3O4, MnO2, SnO2, CoO2, TiO2.

Unlike the conventional methods, the method of electrically determining the formation efficiency of the charge transfer complex according to the present invention is a method of electrically determining the formation rate of the charge transfer complex of the double layer formed at the interface between the first material layer and the second material layer. . That is, a new method for more easily determining the formation efficiency of the charge transfer complex between the host material and the dopant of the organic electronic device by using the electrical conductivity characteristics of the double insect formed only by changing the thickness of the first material layer and the second material layer Can.

Through this, it is possible to easily select and apply an optimal dopant to the host material of the electron transport layer or hole transport layer in which the organic semiconductor and/or inorganic compound in the organic electronic device is used. This can achieve a technical/economic effect in that the optimum dopant can be selected and decided more simply according to the type of host material without directly manufacturing the organic electronic device.

1 is a side view of an organic electronic device of the present invention.
2 is a view schematically showing a phenomenon in which a charge transfer complex is formed in a double layer of an interface of a heterojunction according to an embodiment of the present invention.
3 is a cross-sectional view showing the configuration of the resistance measuring element 200 of the present invention.
4 is a plan view showing the configuration of the electrical conductivity measuring device 300 for calculating electrical conductivity for each channel applied to the organic electronic device of the present invention.
5 is a graph showing the results of measuring voltage/current characteristics for each channel of the present invention.
6 is a graph showing the resistance measured for each channel resistance of the present invention.
7 is a graph showing the result of converting the resistance value measured for each channel of the present invention into electrical conductivity.
8 is a graph showing the results of electrical conductivity according to dopants (MoO3 and CuI) as the first material layer of the present invention.

Hereinafter, the present invention will be described in detail. The following examples and drawings are provided as examples to sufficiently convey the spirit of the present invention to those skilled in the art.

The method for electrically determining the charge transfer complex of the organic semiconductor of the present invention occurs spontaneously by the double layer 180 formed at the interface between the first material layer (inorganic compound layer, 160) and the second material layer (organic compound layer, 170). It may be to use the phenomenon that the moving charge is accumulated.

A junction between homogeneous semiconductors is called a homogeneous junction (homo junction), and a junction between heterogeneous semiconductors is called a heterojunction (hetero junction).

In the method of analyzing the efficiency of forming a charge transfer complex in a doped state by mixing an inorganic compound with an organic compound, nanoparticles have low dispersion efficiency in a host material in which the inorganic compound (first material) is an organic semiconductor compound (second material) Due to the high amount of remaining lumped in size, there is a limitation that it is not possible to precisely perform an analysis on the ratio of formation of a molecule to molecule charge transfer complex (CTC) in an organic semiconductor compound.

Therefore, in the method for determining the formation efficiency of a charge transfer complex in an organic semiconductor according to an embodiment of the present invention, an inorganic compound layer (first material layer, 160) and an organic semiconductor compound layer (heterozygous) having heterojunctions, which are bonding phenomena between hetero semiconductors A method of forming a two-material layer, 170) was used. The first material layer and the second material layer are not particularly limited and may be selected and applied as an organic semiconductor compound layer or an inorganic compound layer, if necessary.

2 is a view schematically showing a phenomenon in which a charge transfer complex is formed in a double layer of an interface of a heterojunction according to an embodiment of the present invention.

Referring to FIG. 2, when the organic semiconductor compound layer (second material layer, 170) is stacked on the inorganic compound layer (first material layer, 160) as a single layer, the inorganic compound corresponding to the dopant and the organic semiconductor compound corresponding to the host material A double layer in which a charge transfer complex is formed at the interface of the liver is formed. When a voltage is applied to the double layer, charge is accumulated at the interface formed by stacking the organic semiconductor compound layer, thereby changing the electrical conductivity characteristics compared to the case in which the double layer is not formed. Can decide.

As an example, as illustrated in FIG. 2, in the first material layer 160 and the double layer (charge transfer complex layer 180) generated at an interface in contact with the first material layer 160, the first material layer 160 becomes MoO 3 as an inorganic compound. The second material layer 170 is an organic semiconductor compound layer, NPB (1,4bis[N-(1-naphthyl)-N'-phenylamino]-4,4'-diamine), 1, 4bis[N- (1-naphthyl)-N'-phenylamino]-4,4'-diamine). As described above, according to the formation of the charge transfer complex 180, the organic semiconductor compound layer NPB has a (+) charge, and the inorganic compound layer molybdenum trioxide (MoO3) has a (-) charge.

As described above, the difference in electrical conductivity properties is different depending on the type of the material constituting the inorganic compound layer (first material layer, 160) and the organic semiconductor compound layer (second material layer, 170) using the method of forming the double layer. Will occur. Since these characteristics have a characteristic that differs depending on the thickness of the first material layer or the second material layer, first, the electrical conductivity of the first material layer is measured, and the first material layer and the second material layer are stacked. The electrical conductivity of the first material layer may be changed as the resulting double layer is formed. By adjusting the thickness of the second material layer, the saturation point of the electrical conductivity by the charge transfer complex can be found. From this, after the double layer is formed, the maximum electrical conductivity can be derived to determine the optimal charge transfer complex formation efficiency.

As a temporary example of the present invention, the inorganic compound layer (first material layer) and the organic semiconductor compound layer (second material layer) may be stacked to form a double layer including a charge transfer complex. The inorganic compound layer (first material layer) of the double layer may act as a dopant in the organic semiconductor compound layer (second material layer). Also, the organic semiconductor compound layer (first material layer) may be p-type doped by the inorganic compound layer (second material layer).

In this way, the first material is added as a dopant to the second material as a host material, and a positive charge or a negative charge may be generated, and transport of electrons or electron carriers may be enhanced.

The host material or dopant may be an organic semiconductor compound or an inorganic compound, and the organic semiconductor compound layer is specifically an electron or electrotransport material, N'-diphenyl-N, N'-(3-methylphenyl)-1,1 '-Biphenyl-4,4'-diamine (N,N'-diphenyl-N,N'-(3-methylphenyl)-1,1'-biphenyl-4,4'-diamin)(TPD), (N ,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine)(N,N'-Bis(naphtalen-1-yl)-N,N'-Bis(phenyl)benzidin) )(NPB), (4,4',4''-Tris(carbazol-9-yl)-triphenylamine, 4,4',4"-tris (N-carbazolyl) triphenylamine) (TCTA), Bphen (Bathophenanthroline), BCP (bathocuproine), rubrene hexadecafluorophthalocyanine (F16CuPc), 11,11,12,12-tetracyanonaphtho-2,6-quinodimethane (11,11,12,12 -tetracyanonaphtho-2,6-quinodimethane (TNAP), 3,6-difluoro-2,5,7,7,8,8-hexacyano-quinodimethane (3,6-difluoro-2,5, 7,7,8,8-hexacyano-quinodimethane, F2-HCNQ), Tetracyanoquinodimethane (TCNQ) and molybdenum tri(1,2-bis(trifluoromethyl)ethane-1,2-dithi Orene (molybdenum tris[1,2-bis(trifluoromethyl)ethane-1,2-dithiolene, Mo(tfd)3)] may be selected from one or more of the inorganic compounds ReO3, MoO3, CuI, V2O5, WO3 , Fe3O4, MnO2, SnO2, CoO2, one or more TiO2 may be selected.

Through the present invention, by forming a double layer formed with a charge transfer complex from a host material or a dopant, it is possible to derive the maximum charge transfer complex formation efficiency to determine the optimal charge transfer complex. From this, the optimal dopant for the host material of the electron transport layer or hole transport layer can be easily determined and applied to the organic electronic device.

In particular, in this case, it can be seen that it is obvious that the electrical conductivity varies depending on the doping content of the inorganic dopant, and thus the luminance, efficiency, and useful life of the organic electronic device are different.

Device fabrication

The resistance measuring element 200 of the organic electronic device according to the type of mixing between the organic semiconductor compound host and the inorganic/organic compound dopant is fabricated as shown in FIG. 3, and also as shown in FIG. 4 to measure accurate electrical conductivity. An electrical conductivity measuring device 300 capable of measuring electrical conductivity by measuring the resistance of each channel forming a plurality of channels having different lengths between electrodes was manufactured.

Specifically, referring to FIG. 3 with respect to the configuration of the resistance measuring element 200, the power supply can supply power through the conducting wire 210, and is an electrode for supplying current on the substrate 105. (115) can be used. A current can be supplied through the ITO electrode 115, and the current is directly connected to the inorganic compound layer 240, and an organic semiconductor compound layer 250 or a second material layer is formed on the inorganic compound layer 240 (the first material layer). It can be formed. The optimum efficiency of the electrical conductivity of the double layer using the resistance measuring element of FIG. 3 was derived by measuring the increase and decrease of the electrical conductivity by changing the thickness of the organic semiconductor compound layer 250.

That is, by analyzing the change in electrical conductivity due to the double layer formed by stacking the organic semiconductor compound layer 250 on the inorganic compound layer 240, an optimal inorganic compound for the organic semiconductor compound was determined.

Accordingly, in order to derive the accurate electrical conductivity of the double layer, since the specific resistivity of the double layer is required, the resistance measuring element of FIG. 3 is used as a resistance measuring element 300 for each channel forming a plurality of channels having different lengths between electrodes as shown in FIG. 4. By measuring the resistance for each channel by enlarged fabrication, the exact resistivity value of the double layer of the organic semiconductor compound layer 250 stacked on the inorganic dopant compound layer 240 was derived to derive the correct electrical conductivity.

At this time, the width of the channel 320 is 0.001 ~ 0.1m, the length of the channel 320 can be manufactured in the range of 1 ~ 1000㎛, more preferably 0.005 ~ 0.05m, the length of the channel 320 is 50 It can be produced in the range of ~ 200㎛.

Determination of the efficiency of charge transfer complex formation by measuring electrical conductivity

The plurality of channels 320 may include two or more electrodes 330, and between these electrodes 330, MoO3 (first material layer) is deposited for each channel (channels 1 to 5). As described above, the electrical conductivity of the inorganic compound layer 240 may be more accurately determined through measurement of electrical conductivity through the plurality of channels 220.

At this time, the thickness of the inorganic dopant compound layer 240 was 1 to 50 nm.

Inorganic compound layer (first material layer) NPB(1,4bis[N-(1-naphthyl)-N'-phenylamino]-4,4'-diamine), 1, 4bis[N-(1-naphthyl)- N'-phenylamino]-4,4'-diamine) layer (second material layer) was deposited, and the electrical conductivity was found to be saturated while changing the thickness.

Referring to FIG. 5, channels are classified into channel 1 (50 μm), channel 2 (75 μm), channel 3 (100 μm), channel 4 (150 μm) and channel 5 (200 μm), and the length of the channel is increased. Resistance increased. Therefore, by measuring the length of each channel for several lengths, from this, the contact resistance, which is the intercept value of the y-axis, was corrected to obtain the specific resistance of only the double layer, and the electrical conductivity was measured therefrom.

6 is a result of measuring the resistance for each channel, and it can be confirmed that the resistance increases linearly with an increase in the length of the resistance value. Referring to FIG. 7, the converted conductivity data converged therefrom.

Through this process, the electrical conductivity of the first material layer (MoO3) used and the second material layer (NPB) were stacked on the first material layer to calculate the electrical conductivity of the double layer.

8 is a graph showing the results of electrical conductivity according to the formation of a double layer using the inorganic compound MoO3 or CuI as the first material layer of the present invention, and using the organic semiconductor compound NPB as the second material layer.

When NPB was formed by laminating NPB as a second material layer on the first material layer, MoO3, the NPB thickness became saturated with electrical conductivity from 8 nm, and the electrical conductivity increased by about 3 times compared to when the double layer was not formed. You can check the log scale.

When CuI was used as the first material layer and NPB was stacked to form a double layer, it was confirmed that the electrical conductivity of the NPB was saturated from 6 nm, and the electrical conductivity increased by about 2 times.

From the above results, it can be determined that MoO3, rather than CuI, can be used as an optimal dopant for an organic semiconductor compound, NPB, as a host material for an organic electronic device.

Through this process, by analyzing the electrical conductivity characteristics of the double layer including the charge transfer complex formed at the interface between the first material layer and the second material layer, an organic electronic device such as an OLED, an organic solar cell or an organic photodetector The optimal dopant can be easily determined as a second material capable of forming an electron transfer complex for a host material (FIG. 8 is only a case where MoO3 and CuI are used as a dopant for NPB as a host material).

As described above, in the present invention, it has been described by specific matters and limited embodiments and drawings, which are provided to help the overall understanding of the present invention, but the present invention is not limited to the above embodiments, and the present invention Various modifications and variations are possible from those who have ordinary knowledge in the field to which they belong.

100: organic electronic device 110: substrate
120: first electrode 130: organic semiconductor layer
140: light emitting layer 150: second electrode
160: first material layer (inorganic compound layer) 170: second material layer (oil-based conductor compound layer)
180: double layer (charge transfer complex layer)
200: resistance measurement element for each channel 210: conductor
240: inorganic dopant compound layer 250: organic semiconductor compound layer
300: electrical conductivity measuring element 310: channel electrode
320: channel 330: electrode

Claims (14)

A method for determining an efficient charge transfer complex, characterized in that the formation efficiency of the maximum charge transfer complex is calculated from the double layer formed by laminating the second material layer on the first material layer as electrical characteristics. According to claim 1,
An electrical charge transfer complex characterized in that the electrical properties of the formation efficiency of the charge transfer complex is calculated from the electrical conductivity of the first material layer and the electrical conductivity of the double layer formed by laminating a second material layer on the first material layer. How to decide. According to claim 2,
The maximum charge transfer complex formation efficiency is a method of determining an efficient charge transfer complex, characterized in that to calculate the electrical conductivity by changing the thickness of the first material layer and the second material layer. According to claim 2,
The electrical conductivity of the first material layer
A step (s10) including a plurality of channels, each of the plurality of channels having at least two electrodes;
Forming a first material layer between the two or more electrodes (s20);
Measuring current and voltage by applying voltage to the plurality of channels (s30);
And obtaining electrical conductivity of the first material layer from the current and voltage measured from the plurality of channels (s40). According to claim 4,
The electrical conductivity on which the double layer is formed is
Forming a double layer by stacking a second material layer on the first material layer (s50);
Measuring a current and a voltage by applying a voltage to a plurality of channels on which the double layer is formed (s60);
And obtaining electrical conductivity in which the bilayer is formed from current and voltage measured from a plurality of channels in which the bilayer is formed (s70). According to claim 4,
Method for determining an efficient charge transfer complex, characterized in that the electrical conductivity of the first material layer and the double layer formed is obtained by a TLM (Trnasmission line method). According to claim 3,
Method for determining an efficient charge transfer complex, characterized in that the thickness of the first material layer and the second material layer is changed in the range of 1 ~ 50 nm. The method of claim 5,
Method for determining an efficient charge transfer complex, characterized in that the length between the two or more electrodes is 1 ~ 1000 ㎛. According to claim 1,
The method for determining an efficient charge transfer complex, characterized in that the first material layer is an inorganic compound or an organic semiconductor compound. According to claim 1,
The method of determining an efficient charge transfer complex, characterized in that the second material layer is an inorganic compound or an organic semiconductor compound. The method according to claim 9 or 10,
The organic semiconductor compound is TPD (N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[l,l-biphenyl]-4,4'diamine, N,N'-bis(3-methylphenyl )-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine), NPB(N,N'-di(l-naphthyl)-N,N'-diphenylbenzidine, N, N'-di(1-naphthyl)-N,N'-diphenylbenzidine), TCTA(4,4',4''-Tris(carbazol-9-yl)-triphenylamine, 4,4',4" -Tris (N-carbazolyl) triphenylamine), Bphen (Bathophenanthroline), BCP (bathocuproine), rubrene, hexadecafluorophthalocyanine (F16CuPc), 11,11,12,12-tetracyanonaphtho-2 ,6-quinodimethane (11,11,12,12-tetracyanonaphtho-2,6-quinodimethane, TNAP), 3,6-difluoro-2,5,7,7,8,8-hexacyano- Quinodimethane (3,6-difluoro-2,5,7,7,8,8-hexacyano-quinodimethane, F2-HCNQ), tetracyanoquinodimethane (TCNQ) and molybdenum tree (1,2- Characterized in that at least one of bis(trifluoromethyl)ethane-1,2-dithiorene (molybdenum tris[1,2-bis(trifluoromethyl)ethane-1,2-dithiolene, Mo(tfd)3]) is selected How to determine an efficient charge transfer complex. The method of claim 9 or 10,
The inorganic dopant compound is ReO3, MoO3, CuI, V2O5, WO3, Fe3O4, MnO2, SnO2, CoO2, TiO2 method of determining an efficient charge transfer complex characterized in that at least one is selected. According to claim 1,
The first material layer and the second material layer is a method for determining an efficient charge transfer complex, characterized in that the host material of the hole transport layer or the electron transport layer of the organic electronic device. According to claim 1,
The first material layer and the second material layer is a method for determining an efficient charge transfer complex, characterized in that the hole transport layer of the organic electronic device or a dopant of the electron transport layer host material.

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