JP2017135379A - Transparent electrode, electronic device, and method of manufacturing the electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent electrode which is chemically stable and has low resistance and high transmittance, and to provide an electronic device and a method of manufacturing the electronic device.SOLUTION: The transparent electrode includes: a conductive layer containing an amorphous inorganic oxide-containing film; and a shielding layer formed on the conductive layer and containing a graphene film containing a self-doping type conductive polymer film containing a bronsted acid anion and a localized cation in a side chain, and/or nitrogen atoms.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a transparent electrode, an electronic device, and a method for manufacturing the electronic device.

  In recent years, energy consumption has increased, and demand for alternative energy to replace conventional fossil energy as a countermeasure against global warming is increasing. Attention has been focused on solar cells as a source of such alternative energy, and its development is underway. Solar cells have been studied for application to various uses, but the flexibility and durability of solar cells are particularly important in order to deal with various installation locations. The most basic single crystal silicon-based solar cell is expensive and difficult to be flexible, and the perovskite solar cell that has attracted attention recently has room for improvement in terms of durability.

  In addition to such solar cells, studies have been made on photoelectric conversion elements such as organic EL elements and photosensors for the purpose of making them flexible and improving their durability. In such an element, an ITO film is usually used as a transparent positive electrode. However, regarding these elements, PEDOT / PSS generally used as a bonding adhesive layer or an anode buffer releases PSS which is a strong acid. The released PSS may diffuse and deteriorate the photoelectric conversion layer and ITO. Moreover, ITO / Ag / ITO which is low resistance and high transparency may be used as a transparent electrode. Although there is an examination example using such an electrode for an element having a PEDOT / PSS layer (for example, Patent Document 1), amorphous ITO (hereinafter sometimes referred to as a-ITO) and silver tend to be deteriorated by acid or halogen. Is strong. In addition, self-doped transparent conductive polymers having excellent pH stability are known (for example, Patent Document 2), but an example used for antistatics is shown.

Japanese Unexamined Patent Publication No. 2014-532025 Patent No. 4040938

  The present embodiment is intended to provide a chemically stable, low-resistance, and high-transparency transparent electrode, an electronic device, and a method for manufacturing the electronic device in view of the above problems.

The transparent electrode according to the embodiment is
A conductive layer containing an amorphous inorganic oxide;
A film containing a self-doped conductive polymer having a Bronsted acid anion and a localized cation in a side chain, a graphene film containing a nitrogen atom, and a film of these, formed on the conductive layer; A shielding layer selected from the group consisting of combinations;
It is characterized by comprising.

  The electronic device according to the embodiment includes an anode, a cathode, and a photoelectric conversion layer, and the anode, the cathode, or both the anode and the cathode are the transparent electrodes. is there.

Furthermore, an electronic device manufacturing method according to the embodiment includes:
Preparing a conductive layer containing an amorphous inorganic oxide;
A shielding layer selected from the group consisting of a film containing a self-doped conductive polymer having an anion of Bronsted acid and a localized cation in the side chain, a graphene film containing a nitrogen atom, and a combination thereof A process of preparing
Preparing a photoelectric conversion layer;
Preparing a counter electrode;
And a step of bonding the respective layers.

The conceptual diagram which shows the structure of the transparent electrode by embodiment. The conceptual diagram which shows the structure of the solar cell by embodiment. The conceptual diagram which shows the structure of the organic EL element by embodiment. The conceptual diagram which shows the manufacturing method of the electronic device by embodiment. The conceptual diagram which shows the structure of another solar cell by embodiment.

  Embodiments will be described in detail below.

[Embodiment 1]
First, the configuration of the transparent electrode according to the first embodiment will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of a transparent electrode 10 according to the present embodiment. In this transparent electrode, a shielding layer 13 is provided on the conductive layer 12.

  The transparent electrode according to the embodiment includes the conductive layer 12 and the shielding layer 13, but may further include the transparent substrate 11. By providing the transparent substrate, it becomes easy to sequentially form the conductive layer 12 and the shielding layer 13 on the transparent substrate. In addition, by using a transparent substrate, when this transparent electrode is used for an electronic device such as a solar battery, the surface on which this transparent electrode is installed can be used as a light receiving surface. Examples of such a transparent substrate material include resin materials such as polyethylene terephthalate (hereinafter referred to as PET) and polyethylene naphthalate (hereinafter referred to as PEN).

  Note that, in an electronic device such as a solar cell, when a transparent electrode is used for either the anode or the cathode, an opaque substrate containing an opaque resin or metal can be used as the counter electrode facing the anode. In this case, the light receiving surface is the light receiving surface on the side where the transparent substrate is installed.

  The conductive layer 12 is a conductive layer containing an amorphous inorganic oxide. This layer is highly conductive, as is a commonly used electrode.

  As an amorphous inorganic oxide, it can select from the generally known arbitrary things. Specific examples include indium doped tin oxide (ITO), fluorine doped tin oxide (FTO), and ZnO. These amorphous inorganic oxides are preferably highly transparent when used as a film.

  The conductive layer may be composed of only the above amorphous inorganic oxide, but may be combined with a highly conductive material such as a metal as necessary. The method of combining is not particularly limited, but for example, a method of laminating a metal thin film on a film containing an amorphous inorganic oxide is preferable. As the metal, silver or a silver alloy is preferable. Specific examples of the alloy include silver-palladium, silver-gold, and silver-tin. The order of stacking the amorphous inorganic oxide-containing film and the metal thin film is not particularly limited, but a structure in which the metal thin film is sandwiched between the inorganic oxide films is preferable. Specifically, ITO / silver alloy / ITO, FTO / silver alloy / FTO, ZnO / silver alloy / ZnO, and the like are preferable.

The shielding layer 13 is
(I) a film containing a self-doped conductive polymer containing an anion of Bronsted acid and a localized cation in the side chain (hereinafter referred to as a polymer film);
(Ii) selected from the group consisting of a graphene film containing nitrogen atoms (hereinafter referred to as N-graphene film) and a combination of (iii) (i) and (ii). This shielding layer has the effect of inhibiting the transfer of harmful substances such as acids and halogens from the photoelectric conversion layer and the buffer layer to the conductive layer while maintaining conductivity and transparency.

  In the embodiment, the self-doped conductive polymer contained in the polymer film is one in which a Bronsted acid group is conjugatedly bonded to a π-electron conjugated polymer, and the polymer itself exhibits conductivity. In the embodiment, the Bronsted acid group is a combination of an anion of Bronsted acid and a cation ionically bonded thereto. This Bronsted acid group is bonded to the side chain of the polymer. Examples of the main chain structure of such a self-doped conductive polymer include polythiophene, polyaniline, polypyrrole, polyphenylene, and polyphenylene vinylene. Examples of the Bronsted acid combined with the polymer include sulfonic acid, carboxylic acid, phosphoric acid, and boric acid.

式中、Ｌは、単結合またはエーテル結合を含んでいてもよい炭化水素鎖であり、Ｂ⁻はブレンステッド酸基のアニオン、Ａ^＋はブレンステッド酸基のカチオンを表し、ｎは重合度を表す数である。また、隣接する繰り返し単位に含まれる２つのＬが結合して環構造を形成していてもよい。なお、式中ではブレンステッド酸基をＢ⁻Ａ^＋で表わしているがＢ⁻の対カチオンとしてはプロトン化したポリチオフェンカチオンも存在しており、一般的にはＡ^＋はブレンステッド酸基のカチオンとポリチオフェンカチオンの混合体である。 The combination of the main chain structure and the Bronsted acid can be arbitrarily selected according to the purpose. For example, the polythiophene represented by the following formula (I) and the following formula (II) are represented. Examples include polyaniline and polypyrrole represented by the following formula (III).

In the formula, L is a hydrocarbon chain that may contain a single bond or an ether bond, B ⁻ represents an anion of the Bronsted acid group, A ⁺ represents a cation of the Bronsted acid group, and n represents the degree of polymerization. It is a number to represent. Moreover, two L contained in the adjacent repeating unit may combine to form a ring structure. In the formula, the Bronsted acid group is represented by B ⁻ A ⁺ , but a protonated polythiophene cation also exists as a counter cation of B ⁻ , and in general, A ⁺ is a cation of the Bronsted acid group. And a mixture of polythiophene cations.

Specific examples of preferable polymers include those having the following structures. Here, all are shown as acid-type structures.

  In these formulas, n, n ', and m are numbers of 1 or more.

  Among these, polythiophene represented by the formula (I), in particular, (Ia) to (Id) is preferable because of its low resistance and chemical stability. As the Bronsted acid, sulfonic acid is preferable because it has the highest doping effect. Any substituent other than the Bronsted acid group may be bonded to these polymers as long as the effects of the embodiments are not impaired. For example, an alkyl group or an ether group is preferable because it increases the solubility of the polymer. The Bronsted acid group may be bonded to an alkyl group or aryl group which is a side chain of the polymer, but it is preferable to bond to the alkyl group from the viewpoint of stability.

  In the case of a self-doped conductive polymer containing a Bronsted acid anion and a localized cation in the side chain, since there is little free Bronsted acid, the conductive layer (amorphous inorganic oxide-containing film or metal thin film) There is little diffusion of acid, and deterioration of the conductive layer due to acid can be prevented. In addition, the Bronsted acid anion of the self-doped conductive polymer is present as an anion, and an anion such as a halogen ion contained in the photoelectric conversion layer can be prevented from diffusing into the conductive layer. Thereby, deterioration of the conductive layer is prevented. It is also possible to prevent anions and the like from entering the photoelectric conversion layer from the conductive layer side of the device. Therefore, durability of electronic devices such as organic solar cells (hereinafter referred to as OPV), solar cells such as perovskite solar cells, and various optical sensors can be improved.

  The localized cation is preferably an alkali metal ion, ammonium ion, or phosphonium ion. As ammonium ions and phosphonium ions, quaternary ammonium ions and quaternary phosphonium ions are more preferred.

  This polymer layer preferably further contains a polyol compound or graphene oxide. This is because the presence of these compounds in the polymer layer improves the adhesion with adjacent layers.

  The N-graphene film is a planar film in which a part of carbon constituting the graphene film made of only carbon is substituted with nitrogen atoms. The N-graphene film may have a single layer structure or a multilayer structure.

  The nitrogen content (N / C atomic ratio) of the N-graphene film according to the embodiment can be measured by an X-ray photoelectron spectrum (XPS), preferably 0.1 to 30 atom%, and 1 to 10 atom%. It is more preferable that

  Such an N-graphene film has a high shielding effect, prevents the deterioration of the electrode containing amorphous oxide and silver alloy by preventing the diffusion of acid and halogen ions, and prevents the entry of impurities from the outside into the photoelectric conversion layer. be able to. Furthermore, since the N-graphene film contains nitrogen atoms, it has a high ability to trap acid, so that the shielding effect is higher.

  Note that the shielding film may have a stacked structure in which an N-graphene film and a polymer film are combined. By laminating these, electrode deterioration can be further prevented. In this case, the N-graphene film is preferably on the transparent conductive film 12 side. This is because the N-graphene layer can prevent free Bronsted acid remaining in the polymer film from diffusing into the conductive layer.

  When the transparent electrode according to the embodiment includes a substrate, the type of the substrate is selected according to the purpose. For example, as the transparent substrate, an inorganic material such as glass, or an organic material such as PET, PEN, polycarbonate, or PMMA is used. In particular, the use of a flexible organic material is preferable because the transparent electrode according to the embodiment is rich in flexibility.

  In addition, the transparent electrode according to the embodiment may further include a buffer layer and a brookite titanium oxide layer (described later in detail). These layers have an effect of preventing the conductive layer from being deteriorated by halogen or the like moving from the photoelectric conversion layer or the like when the transparent electrode according to the embodiment is incorporated into an electronic device.

[Embodiment 2]
The configuration of the photoelectric conversion element according to the second embodiment will be described with reference to FIG. FIG. 2 is a schematic configuration diagram of a solar battery cell 20 (photoelectric conversion element) according to the present embodiment. The solar battery cell 20 is an element having a function as a solar battery that converts light energy of light such as sunlight that has entered the cell into electric power. The solar battery cell 20 includes a photoelectric conversion layer 22 provided on the surface of the transparent electrode 21 and a counter electrode 23 provided on the side surface opposite to the transparent electrode 21 of the photoelectric conversion layer 22.

  Here, the transparent electrode 21 is the same as that shown in the first embodiment. That is, it has a conductive layer containing an amorphous inorganic oxide and a shielding layer selected from the group consisting of a polymer film, an N-graphene film, and a combination thereof.

The photoelectric conversion layer 22 is a semiconductor layer that generates a current by converting light energy of incident light into electric power. The photoelectric conversion layer 22 generally includes a p-type semiconductor layer and an n-type semiconductor layer. Examples of the photoelectric conversion layer include a laminate of a p-type polymer and an n-type material, RNH ₃ PbX ₃ (X is a halogen ion, R is an alkyl group, etc.), a compound semiconductor such as CIGS, and the like.

  As the photoelectric conversion layer 22, a silicon semiconductor, an inorganic compound semiconductor such as InGaAs, GaAs, chalcopyrite, CdTe, InP, or SiGe, a quantum dot-containing type, or a dye-sensitized transparent semiconductor is used. Also good. In either case, the efficiency is high and output degradation can be further reduced.

When a self-doped conductive polymer is used as the material of the shielding layer and the cation is contained in the photoelectric conversion layer, the localized cation contained in the polymer is the same as the cation contained in the photoelectric conversion layer. It is preferable that it is an ion. For example, if the photoelectric conversion layer contains CH ₃ NH ₃ PbX ₃ , the localized cation is preferably a methylammonium ion.

  A buffer layer 24 may be inserted between the photoelectric conversion layer 22 and the transparent electrode 21 in order to promote or block charge injection.

  The counter electrode 23 is usually a metal electrode, but the transparent electrode according to the embodiment may be used. A buffer layer 25 may be inserted between the counter electrode 23 and the photoelectric conversion layer 22 in order to promote or block charge injection.

  When a self-doped conductive polymer layer is used as the shielding layer, a configuration in which the transparent electrode 21 serves as an anode is preferable.

When an N-graphene film is used as the shielding layer, the transparent electrode 21 can be an anode and a cathode. However, when an N-graphene film is used as a shielding layer for the transparent electrode serving as an anode, it is preferable to provide a buffer layer that increases the ionization potential between the N-graphene film and the photoelectric conversion layer 22. Examples of such a buffer layer include vanadium oxide, PEDOT / PSS, p-type polymer, vanadium pentoxide (V ₂ O ₅ ), 2,2 ′, 7,7′-Tetrakis [N, N-di (4- methoxyphenyl) amino] -9,9′-spirobifluorene (hereinafter referred to as Spiro-OMeTAD), nickel oxide (NiO), tungsten trioxide (WO ₃ ), molybdenum trioxide (MoO ₃ ), or the like can be used. .

On the other hand, when an N-graphene film is used as the shielding layer for the transparent electrode serving as the cathode, it is preferable to provide a buffer layer 24 that reduces the work function between the N-graphene layer and the photoelectric conversion layer 22. As such a buffer layer, lithium fluoride (LiF), calcium (Ca), 6,6′-phenyl-C61-butyric acid methyl ester (6,6′-phenyl-C61-butyric acid methyl ester, C60-PCBM) ), 6,6′-phenyl-C71-butyric acid methyl ester (6,6′-phenyl-C71-butyric acid methyl ester, hereinafter referred to as C70-PCBM), indene-C60 bis-adduct (Indene-C60 bisduct, hereinafter) , ICBA), cesium carbonate (Cs ₂ CO ₃ ), titanium dioxide (TiO ₂ ), poly [(9,9-bis (3 ′-(N, N-dimethylamino) propyl) -2,7-fluorene)- alt-2,7- 9,9-dioctyl- fluorene)] (hereinafter, referred PFN), bathocuproine (Bathocuproine, hereinafter referred to BCP), zirconium oxide (ZrO), zinc oxide (ZnO), may be a layer consisting of polyethylene emissions imine.

  Note that a brookite-type titanium oxide layer can be provided instead of the shielding layer or between the shielding layer and the photoelectric conversion layer. Titanium oxide is known to have three types of crystal structures: rutile, anatase, and brookite. In the embodiment, it is preferable to use a layer containing brookite type titanium oxide. This brookite-type titanium oxide layer has an effect of suppressing the movement of halogen from the photoelectric conversion layer to the conductive layer and the movement of metal ions from the conductive layer to the photoelectric conversion layer. For this reason, the lifetime of an electrode or an electronic device can be extended. Such a brookite-type titanium oxide layer is preferably composed of brookite-type titanium oxide nanoparticles, specifically, particles having an average particle diameter of 5 to 30 nm. Here, the average particle diameter was measured with a particle size distribution measuring device. Such brookite-type nanoparticles are commercially available from, for example, High-Purity Chemical Laboratory.

As the counter electrode 23, an electrode having the same structure as the transparent electrode 21 may be used. Further, the counter electrode 23 may contain unsubstituted planar single-layer graphene. The unsubstituted single-layer graphene can be produced by a CVD method using methane, hydrogen, and argon as reaction gases and a copper foil as a base catalyst layer. For example, after the thermal transfer film and single layer graphene are pressure-bonded, copper is dissolved and the single layer graphene is transferred onto the thermal transfer film. By repeating the same operation, a plurality of single-layer graphenes can be laminated on the thermal transfer film, and 2 to 4 graphene layers are produced. A counter electrode can be formed by printing a metal wiring for current collection on the film using silver paste or the like. Instead of unsubstituted graphene, graphene in which part of carbon is substituted with boron may be used. Boron-substituted graphene can be similarly produced using BH ₃ , methane, hydrogen, and argon as reaction gases. These graphenes can also be transferred from a thermal transfer film onto a suitable substrate such as PET.

  Further, these single layer or multilayer graphene may be doped with a tertiary amine as an electron donor molecule. An electrode made of such a graphene film also functions as a transparent electrode.

  For example, a poly (3,4-ethylenedioxythiophene) / poly (styrenesulfonic acid) composite (PEDOT / PSS) film may be formed on the counter electrode 23 as the hole injection layer 25. This film can be, for example, 50 nm thick.

The solar battery cell according to the embodiment can have a structure in which both surfaces are sandwiched between transparent electrodes.
The solar cell having such a structure can efficiently use light from both sides. The energy conversion efficiency is generally 5% or more, and is characterized by long-term stability and flexibility.

  Moreover, an ITO glass transparent electrode can be used as the counter electrode 23 instead of the graphene film. In this case, the flexibility of the solar cell is sacrificed, but light energy can be used with high efficiency. Further, stainless steel, copper, titanium, nickel, chromium, tungsten, gold, silver, molybdenum, tin, zinc, or the like may be used as the metal electrode. In this case, transparency tends to decrease.

  In addition, the photovoltaic cell of this embodiment can be used also as an optical sensor. Since the graphene thin film is transparent from visible light to the infrared region, it can be used as an infrared sensor by using a photoelectric change layer having sensitivity in the infrared region.

[Embodiment 3]
First, the configuration of the photoelectric conversion element according to the third embodiment will be described with reference to FIG. FIG. 3 is a schematic configuration diagram of the organic EL element 30 (photoelectric conversion element) according to the present embodiment. The organic EL element 30 is an element having a function as a light emitting element that converts electric energy input to the element into light. The organic EL element 30 includes a photoelectric conversion layer (light emitting layer) 32 provided on the surface of the transparent electrode 31, and a counter electrode 33 provided on the side surface opposite to the transparent electrode 31 of the photoelectric conversion layer 32.

  Here, the transparent electrode 21 is the same as that shown in the first embodiment.

  The photoelectric conversion layer 32 is an organic thin film layer that recombines the charge injected from the transparent electrode 31 and the charge injected from the counter electrode 33 to convert electric energy into light. The photoelectric conversion layer 32 is usually composed of a p-type semiconductor layer and an n-type semiconductor layer. A buffer layer 35 may be provided between the photoelectric conversion layer 32 and the counter electrode 33 in order to promote or block charge injection, and a buffer layer 34 may also be provided between the photoelectric conversion layer 32 and the transparent electrode 31.

  The counter electrode 33 is usually a metal electrode, but a transparent electrode may be used. A buffer layer 35 may be inserted between the counter electrode 33 and the photoelectric conversion layer (light emitting layer) 32 in order to promote or block charge injection.

  When a self-doped conductive polymer layer is used as the shielding layer, a configuration in which the transparent electrode 31 serves as an anode is preferable.

  When an N-graphene film is used as the shielding layer, the transparent electrode 31 can be an anode and a cathode. However, when an N-graphene film is used as the shielding layer for the transparent electrode serving as the anode, it is preferable to provide a buffer layer that increases the ionization potential between the N-graphene film and the photoelectric conversion layer 32. As such a buffer layer, for example, a layer made of vanadium oxide, PEDOT / PSS, p-type polymer, vanadium pentoxide, Spiro-OMeTAD, nickel oxide, tungsten trioxide, molybdenum trioxide, or the like can be used.

  On the other hand, when an N-graphene film is used as the shielding layer for the transparent electrode serving as the cathode, it is preferable to provide a buffer layer 24 that reduces the work function between the N-graphene layer and the photoelectric conversion layer 22. Examples of such a buffer layer include zinc oxide, titanium oxide, lithium fluoride, cesium carbonate, and polyethyleneimines.

  Note that as in Embodiment 2, a brookite-type titanium oxide layer can be provided instead of the shielding layer or between the shielding layer and the photoelectric conversion layer.

  A transparent electrode similar to the transparent electrode 31 may be used as the counter electrode 33. As the transparent electrode, the graphene film described in Embodiment 2 may be used.

The organic EL device according to the embodiment can have a structure in which both surfaces are sandwiched between transparent electrodes.
The organic EL element having such a structure can emit light on both sides, is stable and flexible for a long period of time.

[Embodiment 4]
A method for manufacturing an electronic device according to the fourth embodiment will be described below with reference to FIG.
The manufacturing method of the electronic device 40 according to the embodiment can be manufactured by bonding the conductive layer 41, the shielding layer 42, the photoelectric conversion layer 43, and the counter electrode 44. Each of these layers and electrodes may be formed independently and then joined, or each layer may be sequentially stacked.
The method for forming each layer will be described as follows.

  The conductive layer 41 may be a single film having no substrate, but may be formed on the surface of the substrate. In general, it is preferable to form a conductive layer on the surface of the substrate in order to facilitate manufacture.

  In the embodiment, the conductive layer 41 is a layer containing an amorphous inorganic oxide. As the amorphous inorganic oxide, ITO or FTO is preferably used. These amorphous inorganic oxide films are generally formed by sputtering. Further, it may be formed by a printing method.

  The conductive layer 41 may have a metal thin film. In the case where the conductive layer includes a metal thin film, the conductive layer may be formed directly on the film including the inorganic oxide or may be attached to the film including the inorganic oxide.

The shielding layer 42 bonded to the conductive layer 41 is any one of (i) a polymer film, (ii) an N-graphene film, and (iii) a combination of a polymer film and an N-graphene film.
When a polymer film is used as the shielding layer, it can be formed by preparing an aqueous solution containing the above self-doped conductive polymer and applying and drying the aqueous solution. The pH of the polymer aqueous solution is preferably 3 or more. By setting such a pH, it is possible for the conjugate base of the Bronsted acid of the self-doped conductive polymer to exist as an anion, and diffusion of anions such as halogen ions contained in the photoelectric conversion layer to the electrode Can be prevented. As a result, it is possible to prevent electrode deterioration and to prevent diffusion of anions and the like from the outside of the device to the photoelectric conversion layer, thereby improving the durability of the electronic device.
In addition, it is preferable that pH of polymer aqueous solution is 11 or less. When a non-self-doped conductive polymer is used as the polymer, it needs to be strongly acidic pH 2 or less, and it becomes difficult to achieve the effects of the embodiment. A polyol compound or graphene oxide can be added to the polymer aqueous solution. Use of these additives is preferable because it improves the adhesion to the adjacent layer. The polymer film can be formed directly on the conductive layer, or the polymer film formed on another substrate can be placed on the conductive layer by transfer or the like.

  When an N-graphene film is used as the shielding layer, the N-graphene film is formed by the following method, for example.

  First, a copper foil is prepared as a base catalyst, and its surface is annealed by laser irradiation to enlarge the crystal grains. Next, on the surface of the copper foil, ammonia, methane, hydrogen, and argon (15: 60: 65: 200 ccm) are used as reaction gases under a condition of 1000 ° C./5 minutes, hereinafter referred to as CVD. ) To produce a film. The obtained film is further treated at 1000 ° C. for 5 minutes under a stream of ammonia and argon, and then cooled under argon, whereby a single-layer N-graphene film can be obtained.

  After the thermal transfer film is pressure-bonded to the surface of the single layer N-graphene film, it is dipped in an ammonia-alkali cupric chloride etchant to dissolve the copper foil, and the single layer graphene is transferred onto the thermal transfer film. By repeating the same operation, a multilayer N-graphene film in which 2 to 4 layers of single-layer graphene are laminated on the thermal transfer film can be obtained.

  In the above-described N-graphene film production method, low molecular nitrogen compounds such as pyridine, methylamine, ethylenediamine, urea, and the like, ethylene, acetylene, methanol, ethanol, etc. are used instead of ammonia gas as the raw material for the CVD method. May be.

The N-graphene film can be formed by other methods. For example, a graphene oxide aqueous dispersion is spin-coated on quartz glass or metal (for example, Cu) to form a thin film, and then heat-treated in a mixed atmosphere of ammonia, hydrogen, and argon to replace nitrogen. Can do. Alternatively, the graphene oxide thin film can be manufactured by heat treatment with hydrazine and drying. Alternatively, an unsubstituted graphene thin film can be produced by processing in a nitrogen plasma.
Furthermore, it can also be produced by applying a nitrogen-containing polymer compound such as polyacrylonitrile or polyimide onto quartz glass or metal to form a thin film and then graphitizing it by heating it in vacuum or under argon. Also, a dispersion of nitrogen-substituted graphene is prepared, and the dispersion is applied to quartz glass, or a film is prepared by filtering the graphene dispersion through a filter and depositing N-graphene on the filter. The film can be prepared by peeling off the film.

  In the transparent electrode according to the embodiment, the N-graphene layer formed in this way is disposed directly on the conductive layer or indirectly on the conductive layer via the polymer film. This installation is generally performed by transferring from a thermal transfer film, as will be described later. At this time, metal wiring for current collection may be formed in the conductive layer in advance.

  In the case where a combination of a polymer film and an N-graphene film is used as the shielding film, it is preferable that an N-graphene film is provided immediately above the conductive layer and a polymer film is formed or installed thereon.

  The formation method of the photoelectric converting layer 43 is appropriately selected according to the material used, and is not particularly limited. For example, in a perovskite solar cell, a photoelectric conversion layer can be formed by applying a perovskite compound precursor solution and drying. Alternatively, a photoelectric conversion layer can be formed by attaching a semiconductor film formed of a semiconductor crystal.

  The counter electrode 44 can be manufactured by an arbitrary method depending on its configuration. The metal thin film can be bonded to the photoelectric conversion layer, or the metal layer can be laminated on the surface of the photoelectric conversion layer by a sputtering method or the like. Moreover, the transparent electrode by embodiment can be joined, and a single layer or a multilayer graphene film can also be joined as an electrode.

  The electronic device 40 is formed by joining the conductive layer 41, the shielding layer 42, the photoelectric conversion layer 43, and the counter electrode 44. The order of these junctions is not particularly limited, and can be performed in any order or simultaneously.

  If necessary, a substrate is bonded to the conductive layer or the counter electrode, or a buffer layer is inserted between the shielding layer 42 and the photoelectric conversion layer 43 and / or between the photoelectric conversion layer 43 and the counter electrode 44. It can also be joined.

  Further, a brookite-type titanium oxide layer may be provided between the buffer layer and the photoelectric conversion layer, or a brookite-type titanium oxide layer may be provided instead of the buffer layer before bonding. This brookite-type titanium oxide layer is particularly preferably combined with a shielding layer including a graphene film. The brookite-type titanium oxide layer can be formed by applying a dispersion liquid in which nanoparticles of brookite-type titanium oxide are dispersed in a polar solvent to the surface of the shielding layer, the buffer layer, or the photoelectric conversion layer, and drying. it can. The concentration of the dispersion is adjusted according to the thickness of the target layer and the performance of the electronic device. In order to maintain the dispersion stability of the nanoparticles, the pH of the dispersion is preferably 1 to 3. As a coating method, any method such as spin coating, bar coating, spray coating and the like can be adopted. After application, drying is preferable by heating to a high temperature, for example, 100 to 150 ° C. In addition, when the concentration of the dispersion is low, aggregation may occur when heating is performed immediately after coating. For this reason, prior to heating, it is preferred that most of the solvent is generally removed at 35 ° C. or less, for example at room temperature, and then heated to high temperature.

  Bonding can be performed by a wet process such as coating, a dry process such as bonding or transfer, or a vacuum process such as sputtering or vapor deposition. Among these, bonding and transfer are preferable because there is no restriction of a solvent and the like, and since it can be performed at a low temperature, there is little element damage. As the bonding surfaces, all surfaces can be bonded by using vacuum bonding or the like. A buffer layer surface having adhesiveness is preferable in terms of device durability, and a self-doped conductive polymer surface is particularly preferable. Here, “joining” includes forming another layer directly on one of the layers.

Example 1
A transparent electrode 10 having the structure shown in FIG. 1 was prepared. In this electrode, a conductive layer having a laminated structure of a-ITO / silver alloy / a-ITO (thickness: 100 nm) is formed on a PET film having a thickness of 150 μm, on which a Bronsted acid anion is localized. A shielding layer which is a self-doped conductive polymer film containing a cation in the side chain is laminated.

A tetramethylammonium hydroxide aqueous solution is added to a 10% aqueous solution of a polythiophene having a sulfonic acid group represented by the following formula (Ia-x) as a self-doped conductive polymer to adjust the pH to 6. This aqueous solution is applied to a conductive layer having a-ITO / silver alloy / a-ITO using a bar coater and then dried at 90 ° C. for 1 hour to produce a transparent electrode.

  When this transparent electrode is immersed in 15% salt water for 3 days, no change is observed in the conductivity or shape of the electrode.

(Example 2)
A transparent electrode 10 having the structure shown in FIG. 1 was prepared. In this electrode, a conductive layer having a laminated structure of a-ITO / silver alloy / a-ITO (thickness: 100 nm) is formed on a 150 μm-thick PET film, and a planar part of carbon atoms is formed thereon. Is substituted with nitrogen atoms, and a shielding layer in which an average of four layers of N-graphene films are stacked is formed.

The shielding layer is prepared as follows. First, the surface of the Cu foil is heat-treated by laser irradiation, and crystal grains are enlarged by annealing. This Cu foil is used as a base catalyst layer, and a planar single layer N-graphene is formed by a CVD method at 1000 ° C. for 5 minutes using ammonia, methane, hydrogen, and argon (15: 60: 65: 200 ccm) as a mixed reaction gas. A membrane is manufactured. At this time, a single-layer graphene film is mostly formed, but two or more N-graphene films are also formed in part depending on conditions. Further, after treatment at 1000 ° C. for 5 minutes under a mixed ammonia / argon stream, cooling is performed under an argon stream. After the thermal transfer film (150 μm thick) and the single layer N-graphene are pressure-bonded, in order to dissolve Cu, the single layer N-graphene film is transferred onto the thermal transfer film by soaking in an ammoniacal cupric chloride etchant. By repeating the same operation, four single layer graphene films are laminated on the thermal transfer film to obtain a multilayer N-graphene film.
After laminating the thermal transfer film on the a-ITO / silver alloy / a-ITO / PET film, it is heated to transfer the N-graphene film onto the a-ITO / silver alloy / a-ITO / PET film and transparent An electrode is produced.

The nitrogen content measured by XPS is 1 to 2 atm% under these conditions. The ratio of carbon atoms to oxygen atoms of the carbon material measured from XPS is 100 to 200.
When this transparent electrode is immersed in 15% salt water for 3 days, there is no change in conductivity or shape.

(Example 3)
A transparent electrode 10 having the structure shown in FIG. 1 was prepared. In this electrode, a conductive layer having a laminated structure of a-ITO / silver alloy / a-ITO (thickness: 100 nm) is formed on a 150 μm-thick PET film, and a planar part of carbon atoms is formed thereon. A shielding layer is formed in which two N-graphene films on the average are stacked with nitrogen atoms substituted.

  The shielding layer was prepared as follows. First, a conductive layer having a laminated structure of a-ITO / silver alloy / a-ITO is prepared. The ITO surface of this conductive layer is made hydrophilic by UV ozone treatment. Next, an aqueous solution of graphene oxide is applied onto the conductive layer that has been subjected to UV ozone treatment with a bar coater. The thickness of the graphene film can be adjusted by the concentration of graphene oxide and the distance between the bar coater bar and the conductive layer. A transparent electrode comprising a two-layer graphene film in which a portion of carbon in the graphene oxide film is replaced with nitrogen atoms after being applied and dried at 90 ° C. for 20 minutes and further treated with hydrated hydrazine vapor at 110 ° C. for 1 hour Is made.

  When this transparent electrode is immersed in 15% salt water for 3 days, there is no change in conductivity or shape.

Example 4
A transparent electrode 10 having the structure shown in FIG. 1 is prepared. In this electrode, a conductive layer having a laminated structure of a-ITO / silver alloy / a-ITO (thickness: 100 nm) is formed on a 150 μm-thick PET film, and a planar part of carbon atoms is formed thereon. Is replaced with nitrogen atoms, and an average two-layer N-graphene film and a self-doped conductive polymer film containing a Bronsted acid anion and a localized cation in the side chain are stacked. ing.

This transparent electrode is prepared by polymer lamination on the transparent electrode obtained in Example 3 in the same manner as in Example 1.
When this transparent electrode is immersed in 20% salt water for 3 days, no change in conductivity or shape is observed.

(Example 5)
A transparent electrode 10 having the structure shown in FIG. 1 is prepared. In this electrode, a conductive layer having a-ITO (thickness: 400 nm) is formed on a PET film having a thickness of 150 μm, and a planar carbon atom is partially replaced with nitrogen atoms, and two layers on average. A shielding layer in which N-graphene films are stacked is formed.

  This transparent electrode is produced in the same manner as in Example 3 by changing the conductive layer.

  When this transparent electrode is immersed in hydrochloric acid at pH 1.5 for 2 days, no change in conductivity or shape is observed. Also, dissolved indium and tin are not detected in the hydrochloric acid after immersion.

(Example 6)
A transparent electrode 10 having the structure shown in FIG. 1 is prepared. In this electrode, a conductive layer having a-ITO (thickness: 400 nm) is formed on a PET film having a thickness of 150 μm, and a planar carbon atom is partially replaced with nitrogen atoms, and two layers on average. The N-graphene film and a self-doped conductive polymer film containing a Bronsted acid anion and a localized cation in the side chain are stacked.

  This transparent electrode is produced in the same manner as in Example 4 by changing the conductive layer.

  An aqueous solution of PEDOT / PSS having a pH of 1.5 is applied to the transparent electrode and dried at 110 ° C. for 15 minutes. When this transparent electrode is left in the atmosphere for 1 week, no change in conductivity or shape is observed. In addition, when the cross section of the transparent electrode after being left is observed with a scanning electron microscope, indium and tin dissolved in the PEDOT / PSS layer are not detected.

(Example 7)
A transparent electrode 10 having the structure shown in FIG. 1 is prepared. In this electrode, a conductive layer having a-ZnO (thickness: 400 nm) was formed on a PET film having a thickness of 150 μm, and a planar carbon atom part of which was replaced with nitrogen atoms on average was 2 A shielding layer is formed in which a N-graphene film as a layer and a self-doped conductive polymer film containing a Bronsted acid anion and a localized cation in the side chain are stacked.

  This transparent electrode is produced in the same manner as in Example 4 by changing the conductive layer.

  An aqueous solution of PEDOT / PSS having a pH of 1.5 is applied to the transparent electrode and dried at 110 ° C. for 15 minutes. When this transparent electrode is left in the atmosphere for 1 week, no change in conductivity or shape is observed. In addition, when the cross section of the transparent electrode after standing is observed with a scanning electron microscope, indium and tin dissolved in the PEDOT / PSS layer are not detected.

(Comparative Example 1)
When a transparent conductive film in which a laminated structure (thickness: 100 nm) of ITO / silver alloy / ITO was formed on a PET film having a thickness of 150 μm was immersed in 25% salt water for 3 days, the conductivity decreased, and the surface A white spot is observed. This white point is formed by the reaction between the silver alloy and chloride ions.

(Comparative Example 2)
When a transparent conductive film in which a conductive layer made of a-ITO (thickness 400 nm) is formed on a PET film having a thickness of 150 μm is immersed in hydrochloric acid having a pH of 1.5, the conductivity decreases. Further, indium and tin dissolved in hydrochloric acid after immersion are detected.

(Example 8)
The solar battery cell shown in FIG. 2 is created. This solar cell
(A) a PET film having a thickness of 150 μm;
(B) a conductive layer having a laminated structure (thickness: 100 nm) of a-ITO / silver alloy / a-ITO, (c) a planar two-layer N-graphene film,
(D) a self-doped conductive polymer film containing a Bronsted acid anion and a localized cation in the side chain;
(E) a perovskite organic-inorganic hybrid photoelectric conversion layer,
(F) a buffer layer;
(G) a planar four-layer N-graphene film (h) a conductive layer having a laminated structure (thickness: 100 nm) of a-ITO / silver alloy / a-ITO, and (i) a PET film having a thickness of 150 μm They are stacked in this order. Here, (c) and (d) constitute the shielding layer, (b), (c) and (d) constitute the transparent electrode according to the embodiment, and (g) and (h) represent the counter electrode. Configure. This counter electrode is also a transparent electrode according to the embodiment, and (g) is also a shielding layer.

  This solar cell is produced by the following method.

  A conductive layer (b) is formed on the PET film (a). Next, the ITO surface of the conductive layer is treated with UV ozone to make it hydrophilic. Next, a graphene oxide aqueous solution is applied onto the ITO surface with a bar coater. After drying at 90 ° C. for 20 minutes, the resultant is treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene film (c) in which graphene oxide is partially substituted with nitrogen atoms. Next, a methylamine aqueous solution is added to a 10% aqueous solution of polythiophene represented by the formula (Ia-x) to adjust the pH to 6, and 5% sorbitol (low molecular polyol compound) is mixed with the polymer. A self-doped conductive polymer aqueous solution is prepared. This aqueous solution is applied onto the N-graphene film (c) using a bar coater and then dried at 90 ° C. for 1 hour to form a polymer film (d), thereby producing a transparent electrode.

The counter electrode and the photoelectric conversion layer are prepared as follows. A conductive layer (h) is formed on the surface of the PET film (i). A four-layer N-graphene film (g) is formed on the surface of this conductive layer in the same manner as in Example 2. A buffer layer (f) is formed on the N-graphene film by applying a toluene solution of C60-PCBM with a bar coater. A dimethylformamide solution (20 wt%) of PbI ₂ was applied thereon with a bar coater, and then an isopropyl alcohol solution (2 wt%) of CH ₃ NH ₃ I was applied with a bar coater and dried at 90 ° C. for 30 minutes. Thus, the photoelectric conversion layer (e) is formed.

The transparent electrode and the photoelectric conversion layer formed on the counter electrode are bonded together in a dry atmosphere at 80 ° C., and the periphery is sealed to produce a solar battery cell having both surfaces transparent.
The obtained solar battery cell shows an energy conversion efficiency of 14% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 5% even if left for one month.

Example 9
The solar battery cell shown in FIG. 2 was created. This solar cell uses 1,4-diaminobutane instead of methylamine for pH adjustment of the polymer aqueous solution, and uses (CH ₃ ) ₂ NH ₂ Br instead of CH ₃ NH ₃ I for the formation of the photoelectric conversion layer. Other than the above, the same method as in Example 8 is used.

  The obtained solar battery cell shows an energy conversion efficiency of 14% or more with respect to 1 SUN sunlight, and the deterioration in efficiency is less than 3% even if left for one month.

(Example 10)
The solar battery cell shown in FIG. 2 was created. This solar cell
(A) a PET film having a thickness of 150 μm;
(B) a conductive layer having a laminated structure (thickness: 100 nm) of a-ITO / silver alloy / a-ITO, (c) a planar two-layer N-graphene film,
(D) a self-doped conductive polymer film containing a Bronsted acid anion and a localized cation in the side chain;
(E) a buffer layer,
(F) a perovskite organic-inorganic hybrid photoelectric conversion layer,
(G) a buffer layer;
(H) Silver electrode layers are laminated in this order. Here, (c) and (d) constitute a shielding layer, and (b), (c) and (d) constitute the transparent electrode according to the embodiment.

This solar cell is produced by the following method.
A conductive layer (b) is formed on the PET film (a). Next, the ITO surface of the conductive layer is treated with UV ozone to make it hydrophilic. Next, a graphene oxide aqueous solution is applied onto the ITO surface with a bar coater. After drying at 90 ° C. for 20 minutes, the resultant is treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene film (c) in which graphene oxide is partially substituted with nitrogen atoms. Next, a methylamine aqueous solution is added to a 10% aqueous solution of polythiophene represented by the formula (Ia-1) to adjust the pH to 6, and 5% sorbitol (low molecular polyol compound) is mixed with the polymer. A self-doped conductive polymer aqueous solution is prepared. This aqueous solution is applied onto the N-graphene film (c) using a bar coater and then dried at 90 ° C. for 1 hour to form a polymer film (d), thereby producing a transparent electrode.

  On the transparent electrode, an aqueous solution of PEDOT / PSS is applied with a bar coater and dried at 100 ° C. for 30 minutes to form a buffer layer (e) (50 nm thickness) containing PEDOT / PSS.

A dimethylformamide solution of PbI ₂ (20 wt%) was applied on the buffer layer (e) with a bar coater, and then an isopropyl alcohol solution of CH ₃ NH ₃ Br (2 wt%) was applied with a bar coater. The photoelectric conversion layer (f) is formed by drying at 90 ° C. for 30 minutes.

  A buffer layer (g) is formed by applying a toluene solution of C60-PCBM with a bar coater on the photoelectric conversion layer (f) and drying it.

  A silver film is produced by sputtering on the buffer layer (g) as the counter electrode (h), and the periphery is sealed to produce a solar battery cell.

  The obtained solar battery cell shows an energy conversion efficiency of 12% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 7% even if left for one month.

(Example 11)
The solar battery cell shown in FIG. 2 is created. This solar cell
(A) Metal thin film electrode (counter electrode) made of stainless steel foil,
(B) a planar two-layer N-graphene film (c) a buffer layer;
(D) a perovskite organic-inorganic hybrid photoelectric conversion layer,
(E) a buffer layer,
(F) a planar two-layer N-graphene film;
(G) A conductive layer made of a-ITO (thickness 400 nm) (h) An auxiliary electrode layer made of copper is laminated in this order. Here, (f) constitutes a shielding layer, and (f) and (g) constitute the transparent electrode according to the embodiment.

  The surface of the stainless steel foil (a) is treated with dilute hydrochloric acid to remove the surface oxide film, and then an aqueous graphene oxide solution is applied with a bar coater to form a graphene oxide film. Next, after drying at 90 ° C. for 20 minutes, it was treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene film (b) in which some of the carbon atoms of graphene oxide were replaced with nitrogen atoms Let

  On the N-graphene film (b), an aqueous solution of PEDOT / PSS is applied with a bar coater and dried at 100 ° C. for 30 minutes to form a buffer layer (c) (50 nm thickness) containing PEDOT / PSS.

A dimethylformamide solution of PbI ₂ (20 wt%) was applied on the buffer layer (c) with a bar coater, and then an isopropyl alcohol solution of CH ₃ NH ₃ Br (2 wt%) was applied with a bar coater. The photoelectric conversion layer (d) is formed by drying at 90 ° C. for 30 minutes.

  A C60-PCBM toluene solution is applied as a buffer layer on the photoelectric conversion layer (d) with a bar coater and dried to form the buffer layer (e).

  A graphene oxide aqueous solution is applied onto the buffer layer (e) with a bar coater. After drying at 90 ° C. for 20 minutes, it is treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene film (f) in which graphene oxide is partially substituted with nitrogen atoms.

  A-ITO is formed on the surface of the N-graphene film (f) by sputtering, and copper is sputtered as an auxiliary electrode to produce auxiliary wiring to form a transparent electrode. Furthermore, a solar battery cell is produced by sealing the periphery.

  The obtained solar battery cell shows an energy conversion efficiency of 12% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 3% even if left for one month.

(Example 12)
The solar battery cell shown in FIG. 2 was created. This solar cell
(A) Metal thin film electrode (counter electrode) made of stainless steel foil,
(B) a polymer layer containing a self-doped conductive polymer (c) a buffer layer;
(D) a perovskite organic-inorganic hybrid photoelectric conversion layer,
(E) a buffer layer,
(F) a planar two-layer N-graphene film;
(G) A conductive layer made of a-ITO (thickness 400 nm) (h) An auxiliary electrode layer made of copper is laminated in this order. Here, (f) constitutes a shielding layer, and (f) and (g) constitute the transparent electrode according to the embodiment.

As a self-doped conductive polymer, a methylamine aqueous solution is added to a 10% aqueous solution of polythiophene having a sulfonic acid group represented by the following formula (Ia-y) to adjust the pH to 7, and 1% graphene oxide with respect to the polymer Were mixed to prepare an aqueous polymer solution. The surface of the stainless steel foil (a) is treated with dilute hydrochloric acid to remove the surface oxide film, and then an aqueous polymer solution is applied with a bar coater and dried at 90 ° C. for 20 minutes to form a polymer film (b).

  On the polymer film (b), an aqueous solution of PEDOT / PSS is applied with a bar coater and dried at 100 ° C. for 30 minutes to form a buffer layer (c) (50 nm thickness) containing PEDOT / PSS.

Next, a dimethylformamide solution of PbI ₂ (20 wt%) was applied on the thermal transfer film with a bar coater, and then an isopropyl alcohol solution of CH ₃ NH ₃ I (2 wt%) was applied with a bar coater. Dry at 90 ° C. for 30 minutes to form a photoelectric conversion layer (d).

  After the thermal transfer film is bonded to the stainless steel foil, the film is heated to transfer the photoelectric conversion layer (d) onto the buffer layer (c), and the thermal transfer film is peeled off.

  On the transferred photoelectric conversion layer (d), a toluene solution of C60-PCBM is applied as a buffer layer with a bar coater and dried to form a buffer layer (e).

  A graphene oxide aqueous solution is applied onto the buffer layer (e) with a bar coater. After drying at 90 ° C. for 20 minutes, it is treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene film (f) in which graphene oxide is partially substituted with nitrogen atoms.

  A-ITO is formed on the surface of the N-graphene film (f) by sputtering, and copper is sputtered as an auxiliary electrode to produce auxiliary wiring to form a transparent electrode. Furthermore, a solar battery cell is produced by sealing the periphery.

  The obtained solar battery cell exhibits an energy conversion efficiency of 10% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 5% even if left for one month.

(Example 13)
The solar battery cell shown in FIG. 2 was created. This solar cell has a configuration in which the perovskite photoelectric conversion layer is replaced with a bulk heterojunction photoelectric conversion layer with respect to the solar cell shown in Example 8, and has the following configuration.
(A) a PET film having a thickness of 150 μm;
(B) a conductive layer having a laminated structure (thickness: 100 nm) of a-ITO / silver alloy / a-ITO, (c) a planar two-layer N-graphene film,
(D) a self-doped conductive polymer film containing a Bronsted acid anion and a localized cation in the side chain;
(E) a bulk heterojunction photoelectric conversion layer;
(F) a planar four-layer N-graphene film (g) a conductive layer having a laminated structure (thickness: 100 nm) of a-ITO / silver alloy / a-ITO, and (h) a PET film having a thickness of 150 μm They are stacked in this order. Here, (c) and (d) constitute the shielding layer, (b), (c) and (d) constitute the transparent electrode according to the embodiment, and (f) and (g) represent the counter electrode. Configure. This counter electrode is also a transparent electrode according to the embodiment.

  This solar cell is produced by the following method.

  The transparent electrode is prepared by the same method as in Example 8 except that sodium hydroxide is used instead of methylamine for adjusting the pH of the aqueous polymer solution, and the pH of the aqueous polymer solution is 7.

  The counter electrode and the photoelectric conversion layer are prepared as follows. A conductive layer (g) is formed on the surface of the PET film (h). A four-layer N-graphene film (f) is formed on the surface of this conductive layer in the same manner as in Example 2. A chlorobenzene solution containing poly (3-hexylthiophene-2,5-diyl) (hereinafter referred to as P3HT) and C60-PCBM is applied onto the N-graphene film with a bar coater and dried at 100 ° C. for 20 minutes. Thus, the photoelectric conversion layer (e) is formed.

  A transparent electrode and a ground photoelectric conversion layer formed on the counter electrode are bonded together in a dry atmosphere at 80 ° C., and the periphery is sealed to produce a solar battery cell having both surfaces transparent.

  The obtained solar battery cell exhibits an energy conversion efficiency of 3% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 5% even if left for one month.

(Comparative Example 3)
The solar battery cell shown in FIG. 2 was created. This solar cell
(A) PET film having a thickness of 150 μm (b) a conductive layer having a laminated structure (thickness: 100 nm) of a-ITO / silver alloy / a-ITO (c) a buffer layer,
(D) a perovskite organic-inorganic hybrid photoelectric conversion layer,
(E) a buffer layer,
(F) Silver electrode layers are laminated in this order.

  This solar cell is produced by the following method.

A conductive layer (b) is formed on the PET film (a). Next, an aqueous solution of PEDOT / PSS is applied onto the conductive layer with a bar coater and dried at 100 ° C. for 30 minutes to form a buffer layer (c) (50 nm thickness) containing PEDOT / PSS.
A dimethylformamide solution of PbI ₂ (20 wt%) was applied on the buffer layer (c) with a bar coater, and then an isopropyl alcohol solution of CH ₃ NH ₃ Br (2 wt%) was applied with a bar coater. The photoelectric conversion layer (d) is formed by drying at 90 ° C. for 30 minutes.

  A buffer layer (e) is formed on the photoelectric conversion layer (d) by applying a toluene solution of C60-PCBM with a bar coater and drying.

  A silver film is produced by sputtering on the buffer layer (e) as the counter electrode (f), and the periphery is sealed to produce a solar battery cell.

  The obtained solar cells exhibit an energy conversion efficiency of 14% or more with respect to 1 SUN sunlight, but the efficiency decreases by 50% or more when left for one month.

(Example 14)
The organic EL element shown in FIG. 3 is created. This organic EL element is
(A) a PET film having a thickness of 150 μm;
(B) a conductive layer having a laminated structure (thickness: 100 nm) of a-ITO / silver alloy / a-ITO, (c) a planar two-layer N-graphene film,
(D) a buffer layer;
(E) photoelectric conversion layer (light emitting layer),
(F) Silver-magnesium electrode layers are laminated in this order. Here, (c) constitutes a shielding layer, and (b) and (c) constitute the transparent electrode according to the embodiment.

  This organic EL element is produced by the following method.

  A conductive layer (b) is formed on the PET film (a). Next, the ITO surface of the conductive layer is treated with UV ozone to make it hydrophilic. Next, a graphene oxide aqueous solution is applied onto the ITO surface with a bar coater. After drying at 90 ° C. for 20 minutes, the resultant is treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene film (c) in which graphene oxide is partially substituted with nitrogen atoms.

  On the N-graphene film (c), an aqueous solution of PEDOT / PSS is applied with a bar coater and dried at 100 ° C. for 30 minutes to form a buffer layer (d) (50 nm thickness) containing PEDOT / PSS.

On the buffer layer (d), N, N′-di-1-naphthyl-N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine (hereinafter referred to as NPD) which is a p-type organic semiconductor. And tris (8-hydroxyquinoline) aluminum (Alq ₃ ) (40 nm), which also functions as an n-type semiconductor and is also a light emitting layer. Further, a silver-magnesium electrode (f) is formed on the light emitting layer (e) by sputtering.

  The obtained organic EL element has little deterioration of the output light, and the decrease in output is 10% even after continuous operation for 1000 hours.

(Example 15)
A compound thin film solar cell is produced as a photoelectric conversion element. Molybdenum is deposited on a stainless steel (SUS304) steel foil. A Cu—Ga film is formed thereon as a photoelectric conversion layer, an In film is formed, a p-type CIGS film is formed by selenization, and a CdS film is formed as an n-type layer thereon. A graphene oxide film is formed thereon by applying an aqueous solution of graphene oxide with a bar coater. Next, after drying at 90 ° C. for 20 minutes, the film is treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene film in which some of the carbon atoms of the graphene oxide are replaced with nitrogen atoms, thereby blocking the shielding layer Is made. Further, a ZnO film containing an alpha component is formed thereon by sputtering. On top of this, aluminum is sputtered as an auxiliary electrode.

  The obtained solar battery cell shows an energy conversion efficiency of 16% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 5% even if left for one month.

  As described above, the transparent electrode according to the embodiment includes a conductive layer containing an amorphous inorganic oxide-containing film, and a Bronsted acid anion and a localized cation formed on the conductive layer in a side chain. A shielding layer containing a self-doped conductive polymer film and / or a graphene film containing nitrogen atoms. This transparent electrode prevents electrode deterioration by preventing diffusion of anion such as halogen ions contained in the photoelectric conversion layer to the electrode and diffusion of acid to the electrode, or photoelectric conversion layer such as anion from the outside And the durability of electronic devices such as solar cells such as perovskite solar cells and organic solar cells, optical sensors and OLEDs can be improved.

In general, when an amorphous inorganic oxide is exposed to an acid, the metal ions contained therein are dissolved and diffused into the photoelectric conversion layer, which tends to cause device deterioration. A film containing a non-self-doped conductive polymer can be formed as a shielding film, in which case the pH of the polymer solution is generally 2 or less in order to prepare the film. On the other hand, when a self-doped conductive polymer is used, the pH of the polymer solution can be 3 or more. When such a polymer solution is used, since the conjugate base of the Bronsted acid of the self-doped conductive polymer exists as an anion, it prevents diffusion of anions such as halogen ions contained in the photoelectric conversion layer to the electrode. Can do. As a result, it is possible to prevent electrode deterioration and to prevent diffusion of anions and the like from the outside into the photoelectric conversion layer, and to improve the durability of solar cells such as OPV and perovskite PV, photosensors and electronic devices. Can do.
The element can be prevented from dissolving metal ions even when the self-doped conductive polymer, N-graphene or their laminated structure according to the present embodiment is formed on the counter electrode side using a metal instead of the transparent electrode side. The lifetime can be extended.

(Example 16)
A solar cell 50 having the structure shown in FIG. 5 is created.

A conductive layer 52 made of ITO / silver alloy / ITO is formed on the PET film 51. Next, the ITO surface of the conductive layer 52 is rendered hydrophilic by UV ozone treatment. Next, a graphene oxide aqueous solution is applied onto the ITO surface with a bar coater. After drying at 90 ° C. for 20 minutes, it is treated with hydrated hydrazine vapor at 110 ° C. for 1 hour to change into a two-layer N-graphene layer 53 in which graphene oxide is partially substituted with nitrogen atoms. The nitrogen content measured by XPS is 4-5 atm% under these conditions. The ratio of carbon atoms to oxygen atoms in the carbon material measured from XPS is 5-10. Next, a solution in which SnCl ₂ is dissolved in 1-butanol is applied with a bar coater. After drying at room temperature for 1 hour in a nitrogen atmosphere, the first buffer layer 54 is manufactured by heating at 130 ° C. for 10 minutes.

Brookite titanium oxide nanoparticles are dispersed in a water / ethanol mixed solvent (adjusted to pH 1.5 with hydrochloric acid) and coated with a bar coater. After drying at room temperature for 1 hour under nitrogen, the brookite titanium oxide layer 55 is produced by heating at 130 ° C. for 10 minutes. Next, a dimethylformamide solution (20 wt%) of PbI ₂ was applied with a bar coater, and then an isopropyl alcohol solution (2 wt%) of CH ₃ NH ₃ Br was applied with a bar coater, and then at 90 ° C. for 30 minutes. By drying, an organic-inorganic hybrid perovskite layer (photoelectric conversion layer) 56 is produced.

  A Ni layer was plated on the PET film 59 to produce a second conductive layer 58 (counter electrode). On top of this, an aqueous solution of PEDOT / PSS to which 5% sorbitol is added is applied with a bar coater and dried at 100 ° C. for 30 minutes to form a second buffer layer 57 (50 nm thickness) containing PEDOT / PSS.

  The second buffer layer 57 is heated to 80 ° C., and is bonded to the organic / inorganic hybrid perovskite layer 56 under the condition that the humidity is 30% or less in the atmosphere, and the surroundings are sealed to manufacture the solar battery cell 50. .

  The obtained solar battery cell shows an energy conversion efficiency of 13% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 5% even if left for one month.

(Example 17)
A solar battery cell is produced in the same manner as in Example 16 except that the graphene layer is produced as follows. First, the surface of the Cu foil is heat-treated by laser irradiation, and crystal grains are enlarged by annealing. This Cu foil is used as a base catalyst layer, and a planar single layer N-graphene is formed by a CVD method at 1000 ° C. for 5 minutes using ammonia, methane, hydrogen, and argon (15: 60: 65: 200 ccm) as a mixed reaction gas. A membrane is manufactured. At this time, a single-layer graphene film is mostly formed, but two or more N-graphene films are also formed in part depending on conditions. Further, after treatment at 1000 ° C. for 5 minutes under a mixed ammonia / argon stream, cooling is performed under an argon stream. After the thermal transfer film (150 μm thick) and the single layer N-graphene are pressure-bonded, in order to dissolve Cu, the single layer N-graphene film is transferred onto the thermal transfer film by soaking in an ammoniacal cupric chloride etchant. By repeating the same operation, four single layer graphene films are laminated on the thermal transfer film to obtain a multilayer N-graphene film. After laminating the thermal transfer film on the a-ITO / silver alloy / a-ITO / PET film, it is heated to transfer the N-graphene film onto the a-ITO / silver alloy / a-ITO / PET film and transparent An electrode is produced.

  The nitrogen content measured by XPS is 1 to 2 atm% under these conditions. The ratio of carbon atoms to oxygen atoms of the carbon material measured from XPS is 100 to 200.

  The obtained solar cell exhibits an energy conversion efficiency of 15% or more with respect to 1 SUN sunlight, and the deterioration of efficiency is less than 5% even if left for one month.

DESCRIPTION OF SYMBOLS 10 ... Transparent electrode 11 ... Transparent substrate 12 ... Conductive film 13 ... Shielding layer 20 ... Solar cell 21 ... Transparent electrode 22 ... Photoelectric conversion layer 23 ... Opposite electrode 24, 25 ... Buffer layer 30 ... Organic EL element 22 ... Transparent electrode 23 ... Photoelectric conversion layer (light emitting layer)
33 ... Counter electrode 34, 35 ... Buffer layer 40 ... Transparent substrate 41 ... Conductive layer 42 ... Shielding layer 43 ... Photoelectric conversion layer 44 ... Counter electrode 50 ... Solar battery cell 51, 59 ... PET film 52 ... Conductive layer 53 ... Two layers N-graphene layers 54, 57 ... buffer layer 55 ... brookite-type titanium oxide layer 56 ... photoelectric conversion layer 58 ... counter electrode

Claims (15)

A conductive layer containing an amorphous inorganic oxide;
A film containing a self-doped conductive polymer having a Bronsted acid anion and a localized cation in a side chain, a graphene film containing a nitrogen atom, and a film of these, formed on the conductive layer; A shielding layer selected from the group consisting of combinations;
The transparent electrode characterized by comprising.   The transparent electrode according to claim 1, wherein the conductive layer is a laminate of the amorphous inorganic oxide-containing film and a metal film containing silver or a silver alloy.   The transparent electrode according to claim 1, wherein the conductive layer is disposed on a transparent substrate.   The transparent electrode as described in any one of Claims 1-3 whose average number of layers of the said graphene film is 2-4.   The transparent electrode as described in any one of Claims 1-4 whose content rate of the nitrogen atom with respect to a carbon atom of the said graphene film is 0.1-10 atom%.   The transparent electrode according to any one of claims 1 to 5, wherein a film containing the self-doped conductive polymer is laminated on the graphene film.   The transparent electrode according to claim 1, wherein the film containing the self-doped conductive polymer further contains a polyol compound or graphene oxide.   An electronic device comprising an anode, a cathode, and a photoelectric conversion layer, wherein the anode, the cathode, or both of the anode and the cathode are transparent electrodes according to any one of claims 1 to 7. An electronic device characterized by   The electronic device according to claim 8, wherein the photoelectric conversion layer contains a perovskite containing a halogen atom.   The electronic device according to claim 9, wherein the localized cation is the same as a cation contained in the perovskite crystal.   The electronic device according to claim 8, wherein the photoelectric conversion layer is an organic thin film containing an organic compound capable of photoelectric conversion.   The electronic device according to any one of claims 8 to 11, wherein the counter electrode facing the transparent electrode is a metal electrode.   A film containing a self-doped conductive polymer having a Bronsted acid anion and a localized cation in the side chain between the metal electrode and the photoelectric conversion layer, a graphene film containing a nitrogen atom, and these The electronic device according to claim 12, further comprising another shielding layer selected from the group consisting of: Preparing a conductive layer containing an amorphous inorganic oxide;
A shielding layer selected from the group consisting of a film containing a self-doped conductive polymer having an anion of Bronsted acid and a localized cation in the side chain, a graphene film containing a nitrogen atom, and a combination thereof A process of preparing
Preparing a photoelectric conversion layer;
Preparing a counter electrode;
And a step of bonding the respective layers. A method of manufacturing an electronic device.   The method according to claim 14, wherein the film containing the self-doped conductive polymer is formed by applying an aqueous polymer solution having a pH of 3 to 11 containing the polymer and drying.

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