KR101413842B1 - organic solar cell devices comprising a layer of inorganic material having 2-dimensional structure - Google Patents

Abstract

The present invention provides an organic solar cell which includes a substrate; an inorganic material layer which is formed on the substrate and has a two-dimensional structure; an anode located on the inorganic material layer; a cathode; and an active layer located between the anode and the cathode. Moreover, the present invention also provides a method of manufacturing a multi-layered structure containing a carbon material layer and an inorganic material layer, which includes the steps of vaporizing a precursor compound of an inorganic material under a reducing atmosphere; forming the inorganic material layer on a metal electrode of an electric furnace after the vaporized precursor compound of the inorganic material is transferred into the electric furnace; vaporizing a precursor compound of a carbon material; and forming the carbon material layer on the inorganic material layer after the vaporized precursor compound of the carbon material is transferred into the electric furnace.

Description

[0001] The present invention relates to an organic solar cell comprising a layer of an inorganic material having a two-dimensional structure,

The present invention relates to an organic solar cell, and more particularly, to an organic solar cell, which comprises a substrate, a layer of an inorganic material having a two-dimensional structure formed on the substrate, an anode disposed on the layer of the inorganic material, , And a cathode. The present invention also relates to a method of manufacturing a multilayer structure including a carbon material layer and an inorganic material layer.

Recently, since the energy consumption has increased dramatically, research and development of new clean energy, which is economical and economical and has high performance, is proceeding. Dual solar cells continue to attract attention as a new energy source capable of meeting the aforementioned requirements and are currently being used as solar cells with monocrystalline silicon, polycrystalline silicon, and amorphous silicon- Silicon-based solar cells.

However, the inorganic silicon solar cell has a complicated manufacturing process and has a problem of high cost. Therefore, it is difficult to supply to the general household until now, and in order to solve the problems, the manufacturing process is simplified, the cost is reduced, There have been many studies on organic solar cells using materials. For example, a dye-sensitized solar cell manufactured using porous titanium oxide, ruthenium dye, iodine, and iodine ion exhibited a high conversion efficiency of about 10 percent (%). Another advantage of the organic solar cell is that it can impart flexible mechanical properties due to the characteristics of the organic material itself. If the substrate is made of a flexible material such as plastic, the entire solar cell element becomes flexible. However, when an organic electronic device is fabricated on a substrate having flexibility, the electrical performance of the electronic device is deteriorated. Indium tin oxide (ITO) is used as the most representative material in the case of an anode used in conventional organic solar cells. ITO is difficult to make a flexible solar cell due to its poor mechanical properties, It has a disadvantage of poor bonding property. In order to overcome these disadvantages, a carbon-based material has been studied as an electrode material for replacing ITO (refer to Non-Patent Documents 1 and 2). However, when a carbon-based material is adhered to a substrate, And thus the characteristics of the transparent electrode are reduced. This is considered to be because the fine irregularities on the surface of the substrate for the element lower the characteristics of the electronic element, and such irregularities adversely affect the mobility of electrons in the electronic element remarkably, or cause a leakage current to occur .

LGD Arco, Y. Zhang, CW Schlenker, K. Ryu, ME Thompson, and C. Zhou, "Continuous, Highly Flexible, and Transparent Graphene Films by Chemical Vapor Deposition for Organic Photovoltaics" ACS Nano, 4 2865-73 (2010) . H. Park, J. A. Rowehl, K. K. Kim, V. Bulovicand, and J. Kong, "Doped Graphene Electrodes for Organic Solar Cells", Nanotechnol., 21 505204 (2010)

SUMMARY OF THE INVENTION It is an object of the present invention to solve the problems occurring at the interface between a substrate for a device and an organic electronic device as described above, and to provide an organic electronic device capable of imparting flexibility without deteriorating the characteristics of the electronic device. Yet another object of the present invention is to provide a multi-layer structure including a carbon material layer and an inorganic material layer suitable for a solar cell economically and simply.

The inventors of the present invention have found that an inorganic material layer having a two-dimensional structure exhibits excellent characteristics in bondability with respect to the anode electrode and surface roughness, so that when the anode is formed on the inorganic material layer, And the present invention has been completed.

According to the present invention,

Board,

A layer of an inorganic material having a two-dimensional structure formed on the substrate,

An anode disposed above the layer of inorganic material,

An active layer located between the anode and the cathode, and

Cathode

To a solar cell.

In a preferred embodiment of the present invention, the anode comprises a carbon material, specifically graphene.

In another embodiment of the present invention, the inorganic material comprises at least one material selected from the group consisting of mica, mica, chalcogen compounds and boron nitride (BN), and more particularly, a hexagonal structure similar to graphene Containing boron nitride.

In a specific embodiment, the solar cell of the present invention further has a hole injection layer between the anode and the active layer. In another specific embodiment, a hole blocking layer is additionally present between the cathode and the active layer.

Preferably, the substrate used in the present invention is a flexible substrate. Further, the substrate may include any material, but may also include a plastic-based material.

In another aspect of the present invention, a method of manufacturing a multilayer structure including a carbon material layer and an inorganic material layer is provided. The production method of the present invention,

Vaporizing a precursor compound of an inorganic material in a reducing atmosphere;

Transporting the precursor compound of the vaporized inorganic material to an electric furnace and forming an inorganic material layer on the metal electrode in the electric furnace;

Vaporizing the precursor compound of the carbon material; And

Transporting a precursor compound of a vaporized carbon material to the electric furnace to form a carbon material layer on the inorganic material layer

. Alternatively, instead of the step of vaporizing the carbon material and the step of forming the carbon material layer, a step of transferring and synthesizing the separately synthesized carbon material layer on the inorganic material layer may be used. In a preferred embodiment, the inorganic material comprises at least one material selected from the group consisting of mica, mica, chalcogen compound and boron nitride, more preferably the inorganic material comprises boron nitride.

In certain embodiments of the present invention, the precursor is Ammonia borane (H ₃ NBH ₃ ), Borizine, and mixtures thereof. It is to the carbon material is yes comprises a pin in the other embodiments, and its precursor compounds include _{CH 4, C 2 H 2,} CH 3 OH, C 2 H 5 OH, or a mixture thereof.

Another aspect of the present invention relates to a multi-layer structure produced by the manufacturing method according to the present invention. The present invention also relates to a solar cell element including the multilayer structure of the present invention.

Hereinafter, the present invention will be described in detail.

The solar cell according to the present invention may have any structure known in the art, but generally includes an anode formed on one surface side of the substrate, a hole injection layer formed on the anode, a hole injection layer formed on the hole injection layer, An active layer for generating electric power, a hole blocking layer formed on the active layer, and a cathode formed on the opposite side of the active layer side in the hole blocking layer. However, the multilayer structure of the solar cell in the present invention is required to have an anode, a cathode, an active layer between the anode and the cathode, an inorganic material layer having a two-dimensional structure between the anode and the substrate, and is not limited to a specific structure. For example, the solar cell of the present invention may have a multi-layer structure of substrate / inorganic material layer / anode / active layer / cathode. In addition, the solar cell of the present invention may have a multilayer structure of a substrate / an inorganic material layer / an anode / a hole injection layer / an active layer / a cathode. The solar cell may have a multi-layer structure of a substrate / an inorganic material layer / an anode / a hole injection layer / an active layer / a hole blocking layer / a cathode. The solar cell may have a multi-layered structure of a substrate / an inorganic material layer / an anode / a hole injection layer / an active layer / a hole blocking layer / a cathode. In the above-described solar cell, the substrate may be embodied as a transparent transparent substrate through which solar light is transmitted, and the anode may also be a transparent electrode.

The substrate is a transparent substrate and is not limited to a colorless transparent substrate. Therefore, the substrate may be embodied as a slightly colored substrate. When the flexibility is not required, the transparent substrate for defining the substrate can be realized as a glass substrate such as soda lime glass and non-alkali glass. However, if flexibility is required, the substrate is not limited to the glass substrate, , A polyamide resin, an epoxy resin, a fluorine resin, and a plastic substrate. Further, the substrate may have light scattering properties due to particles, powder, foam, etc. having a refractive index different from the refractive index of the substrate. When the substrate is not provided on the same side as the light incident surface of the organic solar cell element, the material of the substrate is not particularly limited.

In a specific and preferred embodiment of the present invention, flexible and elongated materials known to those skilled in the art can be selected and used as substrates, and examples thereof include polydimethylsiloxane (PDMS), polyethylene terephthalate (PET), polymethylmethacrylate But are not limited to, polymethylmethacrylate (PMMA), polycarbonate, polyethylene, polypropylene, polystyrene, polyimide, cycloolefin copolymer (COC), and combinations thereof.

In the solar cell of the present invention, a layer of an inorganic material is formed on the substrate, which has at least a two-dimensional structure. The two-dimensional structure of the inorganic material is considered to improve the contact property between the substrate surface and the anode surface, and is expected to reduce the contact resistance, which is one of typical contact characteristics. Examples of such inorganic materials include mica, mica, chalcogen compounds, boron nitride (BN), and the like. The double chalcogen compound includes at least one group 16 (chalcogen) element and at least one positive element means a compound consisting of, and as a non-limiting example, _{MoS 2, MoSe 2, MoTe 2} , WS 2, WSe 2, WTe 2, TiS 2, TiSe 2, TiTe 2 And the like.

In the present invention, the layer of inorganic material may be formed through any method known in the art. For example, in one embodiment, the layer of inorganic material may be deposited by chemical vapor deposition (CVD), thermal or E-beam evaporation (CVD) through chemical reactions including metalorganic chemical vapor deposition (MOCVD) A laser deposition method using a laser beam having a high energy, a sputtering deposition method using a gas ion such as oxygen (O ₂ ), nitrogen (N ₂ ), or argon (Ar), or a sputtering method using two or more sputter guns And a co-sputtering deposition method using a plurality of methods. In a specific embodiment, the inorganic material layer having boron nitride (BN) as a base as the above-mentioned inorganic material layer is deposited on the conductive metal plate such as copper or nickel by the above-mentioned various methods, And preferably within a temperature range of < RTI ID = 0.0 > 1200 C. < / RTI > In some cases, the above-mentioned inorganic material layer such as boron nitride can be transferred by a transfer method to a substrate for solar cell fabrication by using a polymer base material.

An anode, which is an electrode for efficiently collecting holes generated in the active layer on the layer of inorganic material, is formed by a known method of a vacuum deposition method, a sputtering method, and a coating method. The material of the anode may be any material having transparency and sufficient electrical conductivity while having flexibility, and may be a metal, an alloy, a conductive compound, a mixture thereof, and more specifically, a metal such as gold; Conductive polymers such as PEDOT and polyaniline; A conductive polymer doped with any acceptor; And conductive light-transmitting materials such as graphene and carbon nanotubes. The anode preferably has a sheet resistance of several hundreds? /? Or less, preferably 100? /? Or less. The thickness of the anode is arbitrarily determined depending on the light transmittance and the sheet resistance of the anode, but is preferably set to be not more than 500 nm, more preferably not less than 10 nm and not more than 200 nm. In order to transmit solar light to the active layer through the anode, it is preferable that the anode has a light transmittance of 70% or more, preferably 80% or more. The light transmittance in the blue region such as 400 nm is 80% or more, preferably 82% or more, more preferably 85% or more, and most preferably 87% or more.

In one embodiment of the present invention, the anode may be an elongate, transparent electrode comprising a carbon-based material, preferably graphene. The electrode containing the carbon-based material can be manufactured using, for example, a film of a carbon-based material produced by chemical vapor deposition, but is not limited thereto. Among the carbon-based materials, the graphene material is very stable in electrical, mechanical and chemical properties, and it can move electrons 100 times faster than silicon, can flow about 100 times more current than copper, And it is particularly preferable because it is easy to process 1-dimensional or 2-dimensional nanopatterns because it is made of only carbon. By using this, it is possible to control the semiconductor-conductor property of graphene, It is also possible to fabricate a wide range of functional devices such as sensors and memories.

In certain embodiments of the present invention, the anode electrode comprising graphene may be grown by chemical vapor deposition by providing a carbon precursor compound in the metal catalyst layer for graphene growth. The metal catalyst layer may be patterned. The metal catalyst layer may be formed of a material selected from the group consisting of Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Rh, Si, Ta, Ti, W, U, V and Zr, But are not limited to, one or more selected from the group consisting of The metal catalyst layer may be in the form of a thin film and may have a thickness of, for example, from about 1 nm to about 1,000 nm, from about 1 nm to about 500 nm, from about 1 nm to about 400 nm, or from about 100 nm to about 400 nm Lt; / RTI > The carbon precursor compound may be any one as long as it is used as a carbon source in the chemical vapor deposition method in the art. Preferably, CH ₄ , C ₂ H ₂ , CH ₃ OH, C ₂ H ₅ OH, .

In an exemplary embodiment of the present invention, the transparent electrode can be made flexible by transferring the graphene film onto a transparent and / or flexible substrate or other transparent and / or flexible thin film. In an exemplary embodiment, the graphene film may be a transparent thin film having a thickness of about 0.1 nm to about 10 nm, and the sheet resistance of the transparent electrode may be about 1? / Sq to about 1,000? / Sq, It is not.

In certain embodiments of the invention, the anode comprises doped graphene. The dopant added to the graphene may be, for example, a P-type dopant or an N-type dopant, but is not limited thereto. More specifically, the dopant may be at least one selected from the group consisting of an ionic liquid, an ionic gas, an acid compound, and an organic molecular compound, and the dopant may be, for example, NO ₂ BF ₄ , NOBF ₄ , NO ₂ SbF ₆ , HCl, H ₂ PO ₄ , CH ₃ COOH, H ₂ SO ₄ , HNO ₃ , AuCl ₃ , Nafion, SOCl ₂ , Br ₂ , PVDF, dichlorodicyanoquinone, oxone , Dimyristoylphosphatidylinositol, and trifluoromethanesulfonimide can be used.

In the solar cell of the present invention, the cathode efficiently collects electrons generated in the active layer, and is preferably made of a metal and an alloy having a small work function. In order to prevent the difference from the LUMO (Lowest Unoccupied Molecular Orbital) level, the material of the cathode is preferably selected so as to have a work function ranging from 1.9 eV or more to 5 eV or less. In this respect, as the material of the cathode, for example, an alkali metal; Alkaline earth metals; Rare earths; And alloys of these with other metals such as sodium, sodium-potassium alloy, lithium, magnesium, magnesium-silver mixture, magnesium-indium mixture and aluminum-lithium alloy. Aluminum can also be used as a material for the cathode. The cathode is formed by a vacuum deposition method, a sputtering method, a coating method, or the like.

In a solar cell element, an active layer plays a role of converting light into electricity, and typically includes an electron-accepting semiconductor material and an electron-receiving semiconductor material. As a typical example of the electron-injecting type semiconductor, there may be mentioned poly-3-hexylthiophene (hereinafter referred to as P3HT) which is a kind of conductive polymer material, but the material of the electron-injecting type semiconductor is not limited to this and, for example, phthalocyanine A charge transfer agent, a conductive organic charge transfer complex, and a charge transporting agent used in an organic electrophotographic photoconductor, and a charge transport agent used in an organic electrophotographic photoconductor; Other conductive polymer materials, and the like.

Non-limiting examples of the phthalocyanine pigments include divalent pigments having Cu, Zn, Co, Ni, Pb, Pt, Fe, and Mg as a central metal; Phthalocyanine of a trivalent metal in which halogen atoms are coordinated, such as metal-free phthalocyanine, aluminum chlorophthalocyanine, indium chlorophthalocyanine and gallium chlorophthalocyanine; And phthalocyanines in which oxygen is coordinated such as vanadyl phthalocyanine and titanyl phthalocyanine. Non-limiting examples of the polycyclic aromatic compound, the charge transfer agent, the conductive organic charge transfer complex, and the conductive polymeric material capable of imparting electrons include anthracene, tetracene, pentacene, and derivatives thereof; Hydrazone compounds, pyrazoline compounds, triphenylmethane compounds, and triphenylamine compounds; Tetrathiopulevalene and tetraphenyltetrathiopivalene; Those soluble in organic solvents such as P3HT, poly (3-alkylthiophene), polyparaphenylenevinylene derivatives, polyfluorene derivatives, thiophene polymers and oligomers of conductive polymers.

The electron accepting semiconductor used in the active layer is typically implemented with [6,6] -phenyl C61-butyric acid methyl ester (hereinafter referred to as PCBM). However, the material of the electron-receiving semiconductor is not limited thereto, and may be a compound semiconductor nanocrystal having a particle diameter of about 1 nm to about 100 nm; A low-molecular material such as fullerene containing C60, C70, C84 and a conductive polymer material; And carbon nanotubes may be used. The shape of the compound semiconductor nanocrystals is not particularly limited, and may be a rod-like, spherical, or tetrapod shape. Non-limiting examples of the specific material of the compound semiconductor nanocrystals include III-V group compound semiconductors such as InP, InAs, GaP, and GaAs; II-VI group compound semiconductors such as CdSe, CdS, CdTe, and ZnS; Oxide semiconductors such as ZnO, SiO ₂ , TiO ₂ and Al ₂ O ₃ ; CuInSe ₂ ; And CuInS. In a specific embodiment, the active layer is preferably formed so as to have a plurality of rod-like compound semiconductor nanocrystals arranged at intervals of 200 nm or less in contact with the hole blocking layer.

The electron-conducting semiconductor and the electron-receiving semiconductor of the active layer are not limited to a polymer material and are not limited to a low molecular material, and both a high molecular material and a low molecular material may be used.

In a preferred embodiment of the present invention, a hole injection layer is interposed between the anode and the active layer. The hole injecting layer may be made of a compound having a hole transporting ability, a hole transporting effect from the active layer, a good hole transporting effect to the anode, an electron blocking property, and a thin film forming ability. Examples of the non-limiting material include phthalocyanine derivative; Naphthalocyanine derivatives; Porphyrin derivatives; N, N'-bis (3-methylphenyl) - (1,1'-biphenyl-4,4'-diamine (TPD) ] Biphenyl (α-NPD: alpha -NPD), oxazole, oxadiazole, triazole, imidazole, imidazolon stilbene derivative, pyrazoline derivative, tetrahydroimidazole, polyarylalkane (M-MTDATA), and polyvinylcarbazole, polysilane, aminopyridine derivatives, polyethylene dioxythiophene (m-methoxyphenyl) (PEDOT), and the like; inorganic oxides having hole transporting properties such as molybdenum trioxide, vanadium pentoxide, tungsten trioxide, and rhenium oxide; p-type semiconductors such as nickel oxide; and inorganic oxides such as copper oxide Polyethylene dioxythiophene: poly (styrenesulfonate) (PEDOT: PSS) is most preferably used.

In another preferred embodiment of the present invention, a hole blocking layer is interposed between the cathode and the active layer. Examples of the hole blocking layer include, but are not limited to, barocuproine, bazophenanthroline, and derivatives thereof, TPBi, a silole compound, a triazole compound, a tris (8- hydroxyquinolate) - (8-quinolate) aluminum complex, an oxadiazole compound, a distyrylarylene derivative, a silole compound, TPBI (2,2'2 "- (1,3,5- Benzimidazole], and the like. In addition, a material having an optional hole blocking property can be used. The hole blocking layer is usually 10 ^-6 cm ² / Vs or more, preferably 10 ^-5 cm ² / Vs. ≪ / RTI >

Another aspect of the present invention relates to a method of manufacturing a multi-layer structure including a carbon material layer and an inorganic material layer having a two-dimensional structure. In the method of manufacturing a multilayer structure according to the present invention, a multilayer structure in which an inorganic material layer and a carbon material layer are continuously formed on a substrate by chemical vapor deposition to improve contact properties between the two layers can be manufactured. In one embodiment of the present invention, a method for manufacturing a multi-layer structure includes the following steps.

Vaporizing a precursor compound of an inorganic material in a reducing atmosphere;

Transporting the precursor compound of the vaporized inorganic material to an electric furnace and forming an inorganic material layer on the metal electrode in the electric furnace;

Vaporizing the precursor compound of the carbon material; And

Transporting a precursor compound of the vaporized carbon material to the electric furnace to form a carbon material layer on the inorganic material layer.

Non-limiting examples of chemical vapor deposition processes used for the fabrication of multilayer structures include high speed chemical vapor deposition (RTCVD), inductively coupled plasma chemical vapor deposition (ICP-CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition (MOCVD), and plasma enhanced chemical vapor deposition (PECVD).

In a preferred embodiment of the present invention, the inorganic material layer and the carbon material layer may be formed using a chemical vapor deposition (CVD) apparatus as shown in Fig. The constitution of the chemical vapor deposition apparatus is a region F1 in which a precursor source for forming a thin film is activated by a temperature and a region F2 in which an annealing of the metal catalyst layer and an actual chemical vapor phase reaction occur and an inorganic material layer or a carbon material layer is synthesized It is divided. Also, any gas known in the art can be used as the carrier gas for controlling the atmosphere in the CVD apparatus and transporting the precursor source, but an inert gas such as hydrogen gas or argon, nitrogen, helium is commonly used.

As the precursor compound for forming an inorganic material layer used in the production method of the present invention, any known in the art can be used. For example, in order to form a boron nitride layer, ammonia borane, liquid borazine, May be used. In the case of using ammonia borane, a step of preheating to a temperature of 60 DEG C or more may be required to activate.

The carbon material layer may also be of any known method suitable for the individual carbon material. For example, if the carbon material is a graphene material, it can be grown by providing a carbon precursor compound source and heat to a transition metal catalyst layer for graphene growth in a chemical vapor deposition apparatus. For example, the transition metal catalyst layer may be formed of a material selected from the group consisting of Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Rh, Si, Ta, Ti, W, U, V and Zr, And the like. When the transition metal catalyst layer forms a graphene monolayer, the number of graphene layers can be controlled by repeating the transfer process. As the number of graphene layers increases to one, two, or three layers, sheet resistance tends to decrease and conversely light transmittance also decreases. In one embodiment the metal catalyst layer is placed in a chamber and a carbon source such as carbon monoxide, ethane, ethylene, ethanol, acetylene, propane, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene, For example, at a temperature of about 300 ° C. to about 2000 ° C., the carbon components present in the carbon source are combined to form a hexagonal plate-like structure to form graphene. Graphen having the arrangement state is obtained. However, the method of forming graphene on the metal catalyst layer is not limited to the chemical vapor deposition method, and any graphening method known in the art can be used.

The solar cell of the present invention solves the problems related to the contact characteristics between the conventional anode and the substrate by using the inorganic material layer having the two-dimensional structure and also has a multi-layer structure including the inorganic material layer and the carbon material layer suitable for the solar cell element Economical and simple to provide.

1 is a schematic view showing a multi-layer structure of boron nitride and graphene.
2 is a schematic view showing the structure of an example solar cell element according to the present invention.
3 is a graph showing voltage / current characteristics of an exemplary solar cell device according to the present invention.
4 is a schematic view of a chemical vapor deposition apparatus used in the present invention.
5 is an electron micrograph of a BN seed prepared by using a copper foil before nitric acid treatment and a copper foil after nitric acid treatment.
6 is a Raman measurement result of the boron nitride layer produced in the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. As used herein, the terms "comprises" and / or "comprising" do not exclude the presence or addition of one or more other elements, steps, operations, and / or elements . The terms first, second, etc. may be used to describe various elements, but the elements should not be limited by terms. Terms are used only for the purpose of distinguishing one component from another.

Example  1. Boron Knit ride  Fabrication of the layer

A solid source of ammonia borazane (Aldrich) was mounted in a quartz-tubular first chamber (F1) of a chemical vapor deposition (CVD) apparatus and heated to 70-100 ° C to convert it into a gaseous state. (F2) with Ar / H ₂ gas. The nitrile-treated copper foil was mounted in the second chamber, and a boron nitride (BN) layer was obtained after several tens of minutes when the second chamber was heated to 900-1000 ° C. The nitric acid treatment of the copper foil is performed by immersing the copper foil in dilute nitric acid, thereby removing foreign substances and improving the surface of the copper foil. As a result, it is possible to improve the amount, distribution and size of the seed A large and uniform BN seed can be obtained (FIG. 5).

After the copper foil in the second chamber was annealed at a temperature of 1000 캜 or more for 30 minutes or more to flatten the copper foil surface and enlarge the grain size, the BN precursor compound, ammonia borane or borazine source . In the case of ammonia borane source, decomposition and activation by a temperature of 60 ° C or higher was performed, and the activated source moved to the second chamber where synthesis was carried out by the carrier gas and reacted with the copper foil. It was confirmed that the BN layer was formed on the surface of the copper foil by reacting the copper foil and the ammonia borane source at a temperature of 1000 캜 or more for several hours and then stopping supply of the ammonia borane source and cooling the second chamber. In the case of a borazin source, a BN layer can be formed without any additional heat application to the source. The grown BN can be simply identified by Raman measurement (FIG. 6).

Example  2. Grapina  Fabrication of the layer

A gas mixture (CH ₄ : H ₂ : Ar = 15: 8: 8 sccm) containing a carbon source is supplied and introduced into the second chamber F 2 of the CVD apparatus together with N ₂ gas. The second chamber was equipped with a copper foil and the second chamber was heated to 950-1000 ° C to form the graphene layer. Thereafter, an inert gas such as He or Ar was flown in a short time and cooled to room temperature at a rate of 10 DEG C / s or less to obtain a graphene thin film grown on the copper foil.

The above process was further repeated one or two times to obtain a graphene thin film having two or three layers of graphene layers, and its electrical conductivity and light transmittance were measured. As a result, sheet resistance was found to be about 500 Ω / sq to about 50 Ω / sq From about 300 Ω / sq to about 10 Ω / sq, the transmittance was reduced from about 97.1% to about 91.2% for light at about 550 nm wavelength. From these results, it was confirmed that the light transmittance can be controlled by about 2.3% by controlling the number of graphene layers, and the number of graphene layers can be controlled accurately through repetitive transferring process.

In order to improve the electrical conductivity of graphene, a nitric acid solution was put in a closed container, and then graphene was doped by natural vaporization of a nitric acid solution after putting the graphene film. In order to form a graphene anode pattern, a pattern was formed through a shadow mask or a photoresist patterning process, and then the graphene was etched by an oxygen plasma etching method. In order to improve the bonding property with the organic material, the surface of the graphene was converted into hydrophilic by exposing it to strong ultraviolet rays for 10 minutes.

Example  3. Manufacture of solar cell elements

The graphene film obtained in Example 2 was transferred onto the boron nitride (BN) film obtained in Example 1, annealed at 100 ° C for about one hour, and then a copper foil (purity> 99.8% Lt; / RTI > After washing the graphene / BN multilayer film with water, it was transferred to a glass substrate for an organic solar cell, and then a shadow mask was formed to form a necessary electrode pattern. Then, the substrate was etched using an RIE etcher, and then a PEDOT: PSS layer _{, And} P3HT: PCBM layer were sequentially spin-coated. The PEDOT: PSS layer was formed to a thickness of about 80 nm using PEDOT: PSS (CLEVIOS P VP AI4083) as a raw material. Before forming the PEDOT: PSS layer, the surface of the graphene / A solvent such as alcohol, and a UV ozone cleaner.

The active layer P3HT: PCBM is a mixture of P3HT (Sigma Aldrich) as an electron-conducting semiconductor and PCBM (Nano-c, Inc.) as a fullerene derivative as an electron-receiving semiconductor 1: 1. After the mixture was dissolved in an organic solvent, the substrate on which the anode and the hole injection layer were formed was transferred to a glove box in a dry nitrogen atmosphere. Thereafter, a mixed solution of P3HT and PCBM was spin-coated on the hole injection layer to form an active layer with a thickness of 200 nm.

Next, Ca or BaF ₂ as a hole blocking layer was formed on the upper layers by using a vacuum deposition method, and then an aluminum electrode was deposited to complete a solar cell. 3 is a graph showing voltage / current characteristics of an exemplary solar cell device according to the present invention.

Claims (17)

Board,
A layer of an inorganic material having a two-dimensional structure formed on the substrate,
An anode disposed above the layer of inorganic material,
An active layer located between the anode and the cathode, and
Cathode
≪ / RTI > The solar cell according to claim 1, wherein the anode comprises a carbon material. The solar cell according to claim 2, wherein the carbon material is graphene. The solar cell according to claim 1, wherein the inorganic material comprises at least one material selected from the group consisting of mica, mica, chalcogen compound and boron nitride (BN). The solar cell according to claim 4, wherein the inorganic material comprises boron nitride. The solar cell according to claim 1, further comprising a hole injection layer between the anode and the active layer. The solar cell according to claim 1, further comprising a hole blocking layer between the cathode and the active layer. The solar cell according to claim 1, wherein the substrate is flexible. The solar cell according to claim 1, wherein the substrate comprises plastic. Vaporizing a precursor compound of an inorganic material in a reducing atmosphere;
Transporting the precursor compound of the vaporized inorganic material to an electric furnace and forming an inorganic material layer on the metal electrode in the electric furnace;
Vaporizing the precursor compound of the carbon material; And
Transporting a precursor compound of a vaporized carbon material to the electric furnace to form a carbon material layer on the inorganic material layer
And a carbon material layer and an inorganic material layer. 11. The method according to claim 10, wherein the inorganic material comprises at least one material selected from the group consisting of mica, mica, chalcogen compounds and boron nitride. 12. The method according to claim 11, wherein the inorganic material comprises boron nitride. 11. The method of claim 10, wherein the precursor is _{Ammonia borane (H 3 NBH 3)} , Borizine, and method of producing thereof. 11. The method according to claim 10, wherein the carbon material comprises graphene. 11. The method of claim 10, wherein the manufacturing method of the precursor compounds of the carbon material include _{CH 4, C 2 H 2,} CH 3 OH, C 2 H 5 OH, or a mixture thereof. A multi-layer structure produced by the method according to any one of claims 10 to 15. 19. A solar cell comprising the multilayer structure according to claim 16.

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