WO2017217634A1 - Graphene composite electrode and method for manufacturing same - Google Patents

Abstract

Disclosed is a graphene composite electrode and a method for manufacturing same, the graphene composite electrode capable of quickly growing graphene with little defect and treating defects of the graphene to ultimately comprise a high-quality graphene. The graphene composite electrode comprises: a graphene layer; an atomic layer formed on the graphene layer; and a transparent conductive layer formed on the atomic layer.

Description

Graphene composite electrode and method for manufacturing same

The present invention relates to a graphene composite electrode and a method for manufacturing the same, and more specifically, it is possible to grow low-defect graphene more quickly, and heal the defects of graphene to finally contain graphene containing high quality graphene. A composite electrode and a method of manufacturing the same.

Graphene, which has been in the spotlight recently, has very high electrical conductivity and flexibility as well as a transparent property. Therefore, active researches are being made to use it as a flexible transparent electrode or as an electron transport material such as an electron transport layer in an electronic device. It is becoming.

For mass production of graphene-based films, criteria such as graphene synthesis temperature, rate of synthesis, and the possibility of large-area synthesis should be considered. In this regard, methods of synthesizing graphene include a peeling method (also known as a scotch tape method) for physically separating graphene from graphite, and a direct growth method for directly growing graphene on a metal catalyst.

Exfoliation is a method of separating graphene from graphite by physical force, which can produce graphene with low energy, but is defective in graphene and is not suitable for large-area synthesis and mass production.

In general, the direct growth method is a method of directly growing on a metal catalyst by supplying a carbon source such as methane gas to the metal catalyst and performing heat treatment at atmospheric pressure.

Growth of large area graphene begins with the formation of nuclei (growth points) of graphene at any of several points on the metal catalyst growth substrate. Graphene grows from each nucleus site and defects occur at the grain boundaries where the grown graphene domains meet. In addition, since the growth point of the graphene is arbitrarily selected, a problem arises that the size of the graphene domain is not constant, and this problem occurs more seriously in large-area graphene synthesis.

1 is an SEM image of graphene synthesized by the direct growth method. Referring to FIG. 1, the boundary and wrinkles of the graphene domain may be identified, and a large number of predecessors and point defects may be present. The boundaries, wrinkles and dots due to the collision between the graphene domains act as defects that adversely affect the electrical properties of the graphene.

Therefore, there is a need for the development of technology capable of producing large-area graphene of excellent characteristics by minimizing defects of graphene.

The present invention has been made to solve the above problems, an object of the present invention, it is possible to grow a low-defect graphene faster, heal the defects of graphene to finally include a high quality graphene The present invention provides a graphene composite electrode and a method of manufacturing the same.

Graphene composite electrode according to an embodiment of the present invention for achieving the above object is a graphene layer; An atomic layer formed on the graphene layer; And a transparent conductive layer formed on the atomic layer.

The atomic layer may be formed by arranging atoms in a defect region existing on the graphene layer. The atomic layer may be a layer of atoms of a metal or metal oxide.

According to another aspect of the invention, the graphene growth step of growing graphene on the metal catalyst growth substrate; Performing an atomic layer deposition process on the graphene layer to form an atomic layer; And a transparent conductive layer forming step of forming a transparent conductive layer on the atomic layer.

The graphene composite electrode manufacturing method according to the present invention may further include a metal catalyst growth substrate pretreatment step in which at least one pretreatment step of a light irradiation process and a heat treatment process is performed on the metal catalyst growth substrate before the graphene growth step. have.

The atomic layer may be formed by repeating the atomic layer deposition process a plurality of times.

The transparent conductive layer forming step may be performed by a deposition process or a coating process.

Graphene composite electrode manufacturing method according to the present invention comprises the steps of removing the metal catalyst growth substrate; And attaching the flexible substrate on the graphene layer.

Electrode manufacturing method for a transparent substrate based electronic device according to another aspect of the present invention is a graphene growth step of growing graphene on a metal catalyst growth substrate; Performing an atomic layer deposition process on the graphene layer to form an atomic layer; Forming a transparent conductive layer on the atomic layer; Removing a portion of the metal catalyst growth substrate to form a bus electrode; And attaching the bus electrode to the flexible substrate.

The forming of the atomic layer may be performed by arranging atoms in a defect region existing on the graphene layer.

Metal catalyst growth substrates include Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, brass, bronze, cupronickel and stainless steel. One or more metals or alloys thereof selected from the group consisting of steel and Ge.

The forming of the bus electrode may be performed by removing a portion of the metal catalyst growth substrate so that the graphene layer is exposed.

Forming the bus electrode includes placing a mask on the metal catalyst growth substrate; And etching the metal catalyst growth substrate.

Flexible substrates include polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polyethylenenaphthalate (PEN), polycarbonate (PC) and polyimide (PI). It may include any one of).

According to another aspect of the invention, the graphene growth step of growing graphene on the metal catalyst growth substrate; Performing an atomic layer deposition process on the graphene layer to form an atomic layer; A first transparent conductive layer forming step of forming a transparent conductive layer on the atomic layer; Forming an electrochromic part including an electrochromic layer, an electrolyte layer, and an ion storage layer on the first transparent conductive layer; A second transparent conductive layer forming step of forming a transparent conductive layer on the outermost layer of the electrochromic part; Removing a portion of the metal catalyst growth substrate to form a bus electrode; And attaching a bus electrode to the flexible substrate.

According to another aspect of the invention, the flexible substrate; A bus electrode formed on the flexible substrate; A graphene layer formed on the electrical connection portion; An atomic layer formed on the graphene layer; And a transparent conductive layer formed on the atomic layer.

As described above, in the graphene composite electrode according to the exemplary embodiments of the present invention, the graphene layer is grown on the metal catalyst substrate on which the substrate is pretreated. The crystal structure of the metal catalyst substrate is aligned by the pretreatment, and the occurrence of defects in the graphene layer is suppressed under the influence of the aligned catalyst substrate, thereby forming a high quality graphene layer. In addition, the pretreatment of the growth substrate enables the growth of graphene in a faster time than the conventional, it is possible to obtain a manufacturing cost reduction effect due to efficient process execution.

In addition, the defects caused by breakage between the grain boundaries of the prepared graphene, that is, graphene domains, which seriously degrade the electrical properties of the graphene, are healed by applying an atomic layer of homogeneous or heterogeneous material. Through this healing process, it is possible to improve the quality of graphene, and thereafter, there is an effect of minimizing the quality deterioration due to a high energy application process such as an ITO layer deposition process.

In addition, not only the physical strength of the graphene but also the high-quality graphene ensures the conductivity of the device, thereby minimizing the required thickness of the transparent conductive layer, thereby increasing the flexibility of the device and excellent transparency. In addition, graphene acts as a barrier between the transparent conductive layer and the growth substrate to prevent constituents of the growth substrate from diffusing into the transparent conductive layer, thereby maintaining high conductivity and transparency of the transparent conductive layer, thereby producing a high-quality high reliability transparent electrode. It can be effective.

In addition, when the electrode for a transparent substrate-based electronic device constituting the bus electrode using the graphene growth metal catalyst layer according to the embodiments of the present invention and a method of manufacturing the same, defects that the graphene retains have a size similar to that of the defect. Since the atomic layer is applied and cured, high quality graphene can be used as an electrode substrate, and the quality degradation due to defects can be minimized even in a process of applying high energy such as a transparent conductive layer, for example, an ITO layer forming process. There is an effect that can maintain the quality of the transparent electrode used in the electrochromic device.

In addition, the conductivity of the device is ensured due to the high quality graphene, thereby minimizing the thickness of the transparent conductive layer, thereby obtaining an electrode having excellent flexibility and transparency of the device. In addition, graphene acts as a barrier between the transparent conductive layer and the growth substrate, thereby preventing the constituents of the growth substrate from diffusing into the transparent conductive layer, thereby maintaining the conductivity and transparency of the transparent conductive layer, thereby producing a high-quality high-reliability transparent substrate. It has an effect.

In addition, the formation of a bus electrode for applying electricity is essential for the operation of the device using the graphene composite electrode. In order to configure the flexible transparent substrate, the conductive substrate used for graphene growth is removed and a flexible substrate is attached. According to the embodiments of the present invention, a part of the graphene growth substrate is left behind only a desired pattern in the removing step of the conductive substrate. By eliminating the additional bus electrode configuration step, the bus electrode required for driving the device can be formed.

1 is an SEM image of graphene synthesized by the direct growth method.

2 to 7 are views provided for the description of the graphene composite electrode manufacturing method according to an embodiment of the present invention.

8 to 10 are graphs illustrating graphene in which an atomic layer is formed according to different embodiments of the present invention.

11 to 13 are views provided to explain an electrode manufacturing method for a transparent substrate-based electronic device according to another embodiment of the present invention, Figure 14 is a cross-sectional view taken along line AA 'of FIG.

15 to 17 are views provided to explain a method of manufacturing an electrochromic device among transparent substrate-based electronic devices according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. In the accompanying drawings, there may be a component having a specific pattern or having a predetermined thickness, but this is for convenience of description or distinction. It is not limited only.

2 to 7 are views provided for the description of the graphene composite electrode manufacturing method according to an embodiment of the present invention. The graphene composite electrode manufacturing method according to the present embodiment includes a graphene growth step of growing graphene on a metal catalyst growth substrate; Performing an atomic layer deposition process on the graphene layer to form an atomic layer; And a transparent conductive layer forming step of forming a transparent conductive layer on the atomic layer. In the present embodiment, before the graphene growth step, the metal catalyst growth substrate pretreatment step in which at least one pretreatment of the light irradiation process and the heat treatment process is performed on the metal catalyst growth substrate may be further performed.

Graphene to be prepared in the present invention is a plurality of carbon atoms are covalently linked to each other to form a polycyclic aromatic molecule to form a layer or sheet form. The carbon atoms covalently linked in the graphene layer form a 6-membered ring as a basic repeating unit, but the graphene layer may further include a 5-membered ring or a 7-membered ring. In particular, when the growth direction of graphene is different at the domain boundary of graphene, each domain collides to form a 5-membered ring or a 7-membered ring, and such irregular crystal arrangements cause the degradation of graphene. The domain of graphene refers to a region in which crystal grows as a result of graphene growth from any point and thus causes horizontal expansion. That is, the graphene within the boundary formed at the point where the region of the graphene formed from one point and the region of the graphene formed at the other point meets is called a domain. At the interface of the graphene domain, irregular contact is generated when the domains contact each other due to the difference in growth direction of different domains, and such irregularity acts as a defect of graphene.

Graphene is a single layer of covalently bonded carbon atoms (usually sp2 bonds). Graphene may have a variety of structures, such a structure may vary depending on the content of 5-membered and / or 7-membered rings that can be included in the graphene. The graphene may be composed of a single layer of graphene as described above, but it is also possible to form a plurality of layers by stacking them together with each other, and the side end portion of the graphene may be saturated with hydrogen atoms.

Graphene may be synthesized in various ways. In this embodiment, the graphene is synthesized by a direct growth method in which graphene is directly synthesized on a metal catalyst growth substrate. The metal catalyst growth substrate 110 functions as a base layer for growing graphene, and is not limited to a specific material. For example, the metal catalyst growth substrate 110 may include Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, and brass. And one or more metals or alloys thereof selected from the group consisting of bronze, copper, copper, stainless steel and Ge.

 In the present embodiment, before the graphene growth step, the metal catalyst growth substrate pretreatment step in which at least one pretreatment of the light irradiation process and the heat treatment process is performed on the metal catalyst growth substrate may be further performed. The crystal structure of graphene is influenced by the crystal structure of the metal catalyst growth substrate 110. When the crystal structure of the metal catalyst growth substrate 110 is uniform, the graphene is grown to have a uniform crystal structure. In contrast, when the metal catalyst growth substrate 110 has a polycrystalline structure, the crystals of graphene do not grow more uniformly than the monocrystalline structure, and thus the quality of the graphene may be degraded.

Before the growth of graphene, a pretreatment process of the metal catalyst growth substrate 110 may be performed. The pretreatment process performed on the metal catalyst growth substrate 110 is to rearrange the crystal structure of the metal catalyst growth substrate 110 and may include at least one of light irradiation and heat treatment (FIG. 2). By performing such a pretreatment process, the quality of the graphene layer 120 is improved and the graphene layer 120 can be grown in a shorter time, thereby reducing the process cost.

The light irradiation may be performed by irradiating at least one of an intense pulsed light (IPL) and a laser light. That is, the crystals of the catalyst substrate are aligned by light irradiation to the metal catalyst growth substrate 110 having a polycrystalline structure.

The IPL irradiation may align the crystal structure of the metal catalyst growth substrate 110. IPL generally means light of a wide band of 350 nm to 1200 nm, and may be irradiated using a flash lamp or a xenon lamp. IPL irradiation has the advantage that the surface of the growth substrate can be recrystallized without damaging the substrate because it irradiates light at a high speed in a pulse form and heats only a specific region instantly.

Irradiation of the laser light may be irradiated using any one selected from among Nd: YAG laser, CO ₂ laser, argon laser, excimer laser and diode laser.

The heat treatment of the metal catalyst growth substrate may be performed by heating the metal catalyst growth substrate 110 at a temperature of 200 ° C. or more and 1000 ° C. or less.

The metal catalyst growth substrate 110 may further include a catalyst layer (not shown) that adsorbs carbon well to facilitate the growth of graphene. The catalyst layer is not limited to a specific material and may be formed of the same or different material as the metal catalyst growth substrate 110. On the other hand, the thickness of the catalyst layer is also not limited, and may also be a thin film or a thick film.

After the pretreatment process of the metal catalyst growth substrate 110 is performed, a graphene growth step of growing graphene on the metal catalyst growth substrate 110 is performed. As a method of forming the graphene layer 120 on the metal catalyst growth substrate 110, chemical vapor deposition (CVD) may be used. The chemical vapor deposition method is a high temperature 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) Or chemical vapor deposition (PECVD) or the like.

The metal catalyst growth substrate 110 is introduced into the reactor, and under the conditions of supplying a reaction gas utilized as a carbon source, the graphene layer 120 may be formed through atmospheric pressure heat treatment.

Heat treatment temperature for graphene growth may be 300 ℃ to 2,000 ℃. As such, when the metal catalyst growth substrate 110 is reacted with a carbon source at a high temperature and normal pressure, the supplied carbon is dissolved or adsorbed on the metal catalyst growth substrate 110, and then the dissolved carbon atoms are dissolved and adsorbed on the metal catalyst growth substrate 110. Crystallization at the surface forms a graphene crystal structure.

In the above-described process, the number of layers of the graphene layer 120 may be adjusted by adjusting the type and thickness of the metal catalyst growth substrate 110 (including the catalyst layer), the reaction time, the cooling rate, the reaction gas concentration, and the like.

Carbon sources may include carbon monoxide, carbon dioxide, methane, ethane, ethylene, ethanol, acetylene, propane, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene, toluene and the like.

Graphene is synthesized while supplying a reaction gas containing a carbon source to the gas phase, controlling the temperature to form a hexagonal plate-like structure on the surface of the metal catalyst growth substrate 110 by controlling the temperature (FIG. 3).

Referring to FIG. 3, a graphene crystal structure 121 having a hexagonal structure is formed on the graphene layer 120, and three graphene domains collide with each other to form a graphene domain boundary 122. This graphene domain boundary 122 breaks the crystal structure of the ideal hexagonal structure of the graphene layer 120, which acts as a defect 122 of graphene. That is, since the conductivity of the graphene layer 120 is deteriorated and leakage current is generated, there is a problem that product reliability deteriorates when manufacturing a transparent electrode using the graphene layer 120. In addition, the graphene defect 122 becomes a region in which energy and the like aggregate at high temperature and high pressure when performing the post process, thereby further damaging the graphene layer 120.

In the graphene composite electrode manufacturing method according to the present invention, the atomic layer 130 is formed by performing an atomic layer deposition process on the graphene layer as a method of curing the graphene defect 122. Referring to FIG. 4, an atomic layer is deposited on the graphene defect 122. In the present invention, the meaning that the atomic layer 130 is formed on the graphene layer 120 means that the graphene is positioned on the upper surface of the graphene layer 120 in addition to the state in which the atomic layers are arranged in layers such as one layer and two layers. It is a concept including an atomic line forming a portion of a state where an atomic line is arranged to apply a defect to a portion of the fin defect 122. This type of atomic arrangement can be realized by performing an atomic layer deposition (ALD) process.

In the ALD process, a precursor gas of an atom to be deposited is injected and a reaction gas is injected together to form a thin film by laminating atoms in a deposition target layer in a layer.

For example, one atomic layer 130 is formed on the graphene layer 120 through a plurality of ALD processes. However, due to the graphene defect 122 present on the graphene layer 120, the atomic layer 130 is not formed as a single layer over the graphene layer 120 as the ALD process is performed. 122). That is, an atomic layer formed by ALD is formed along the graphene defect 122 as shown in FIG. 4.

In addition, since the graphene defect 122 is a region where energy is easily collected, damage may be intensified in the defect region if a process of applying high energy (heat or plasma) is performed in a subsequent process. However, when the atomic layer 130 is applied to the graphene defect 122, it is possible to prevent the energy from being concentrated in the defect portion of the graphene. Formation of the atomic layer 130 will be further described below with reference to FIGS. 8 to 10.

When the atomic layer 130 is formed on the graphene layer 120, the transparent conductive layer 140 is formed on the atomic layer 130 (FIG. 5). The transparent conductive layer 140 is formed of a transparent material, for example, indium tin oxide (ITO), indium zinc oxide (IZO), F-doped tin oxide (FTO), antimony tin oxide (ATO), AZO (ZnO: Al), GZO (ZnO: Ga), a-IGZO (In ₂ O ₃ : Ga ₂ O ₃ : ZnO), MgIn ₂ O ₄ , Zn ₂ SnO ₄ , ZnSnO ₃ , (Ga, In) ₂ At least one metal oxide selected from O ₃ , Zn ₂ In ₂ O ₅ , InSn ₃ O ₁₂ , In ₂ O ₃ , SnO ₂ , Cd ₂ SnO ₄ , CdSnO _3, and CdIn ₂ O ₄ , or Cu, Al, Sn, One or more metals selected from Ni, W, Ti, Cr, Co, Zn, Ta, V, Au, Ag, TiN, and Pt, or may include nanowires such as Cu or Ag.

The transparent conductive layer 140 may be formed using a physical or chemical deposition process such as thermal deposition, chemical vapor deposition, or sputtering, or may be formed using a coating process.

The graphene composite electrode 100 according to the present invention may be used as a transparent electrode. The flexibility and transparency of the graphene layer 120 can be used alone as a transparent electrode by using the advantages of thin thickness, but it is difficult to use alone as it is difficult to achieve the required level of conductivity as an electrode. Although the transparent conductive layer 140 exhibits high transparency and conductivity, it is difficult to be implemented as a flexible electrode because of its low flexibility, and the thickness of the electrode becomes thick in order to secure high conductivity, thereby decreasing transparency and flexibility, and thus desired quality when used alone. Is difficult to achieve.

The graphene composite electrode 100 according to the present invention includes the transparent conductive layer 140 together on the graphene layer 120 to compensate for the low conductivity of the graphene layer 120 and the thickness of the transparent conductive layer 140. To increase transparency and flexibility. In addition, in the graphene composite electrode 100 according to the present invention, a graphene layer 120 is formed between the metal catalyst growth substrate 110 and the transparent conductive layer 140 to heat-process the transparent conductive layer 140. In order to prevent impurities from flowing through the metal catalyst growth substrate 110, the conductivity and transparency of the transparent conductive layer 140 may be maintained.

When the transparent conductive layer 140 is formed, the metal catalyst growth substrate 110 is removed (FIG. 6), and the flexible substrate 150 is attached to the graphene layer 120 (FIG. 7). The graphene composite electrode 100 from which the metal catalyst growth substrate is removed includes a graphene layer 120; An atomic layer 130 formed on the graphene layer 120; And a transparent conductive layer 140 formed on the atomic layer 130.

The flexible substrate 150 is a substrate exhibiting flexibility, and for example, a plastic substrate, for example, polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polyethylene naphthalate (polyethylenenaphthalate), and the like. , PEN), polycarbonate (PC), and polyimide (PI).

Removal of the metal catalyst growth substrate 110 may be performed using a roll to roll apparatus including a chamber containing an etching solution and a chamber containing the etching solution for selectively removing the metal catalyst growth substrate 110. . The etching solution may be selected according to the type of the metal catalyst growth substrate 110. Examples of the etching solution may include hydrogen fluoride (HF), buffered oxide etch (BOE), ferric chloride (FeCl ₃ ) solution, or second nitrate. Iron (Fe (NO ₃ ) ₃ ) solution.

8 to 10 are graphs illustrating graphene in which an atomic layer is formed according to different embodiments of the present invention. The atomic layer 130 is intensively arranged on the graphene defect 122 of the graphene layer 120, which is preferentially deposited on the graphene defect 122 in which the arrangement of atoms according to the ALD process is relatively energy-aggregated. It can be interpreted as.

An atomic layer 130 of a metal or a metal oxide may be formed as the atomic layer 130. For example, a metal oxide atomic layer such as aluminum oxide or zinc oxide may be formed. Since the aluminum oxide has an atomic layer diameter of about 0.67 Å, in the case of the graphene layer 120 having a thickness of 1 to 10 nm, the graphene domain is formed inside the graphene defect 122 or gathers near the graphene defect 122. It may be formed in a line shape along the boundary 122.

As such, when the atomic layer 130 is formed around the graphene defect 122, the graphene defect 122 is performed when a high temperature / high energy process for forming the transparent conductive layer 140, for example, a plasma deposition process, is performed. This can prevent the energy from being concentrated. Therefore, the expansion of the graphene defects 122 and the deterioration of the physical properties of the graphene layer 120 may be prevented when the transparent conductive layer 140 is formed.

The atomic layer 130 may be formed by repeating the atomic layer deposition process a plurality of times. Referring to FIG. 9, an additional atomic line is formed in the atomic layer of FIG. 8 by further performing the atomic layer deposition process. The number of depositions of the atomic layer may be selected in consideration of the thickness of the graphene layer 120 and the size or frequency of the graphene defects 122.

If the atomic layer deposition process is repeated a plurality of times, the atomic layer 130 may be implemented as one layer as shown in FIG.

The atomic layer 130 may include a metal or a metal oxide as described above, but may be formed so as not to adversely affect the conductivity of the graphene layer 120 or the transparent conductive layer 140. That is, a slight drop in conductivity may occur in the graphene layer 120 due to the introduction of a heterogeneous material of an oxide type, but because it is an atomic unit layer, it does not adversely affect the conductivity of the transparent conductive layer 140. Since the defects generated while forming the 140 are minimized, the influence of the atomic layer on the graphene composite electrode 100 can be ignored.

11 to 13 are views provided to explain an electrode manufacturing method for a transparent substrate-based electronic device according to another embodiment of the present invention, Figure 14 is a cross-sectional view taken along line AA 'of FIG. Electrode manufacturing method for a transparent substrate-based electronic device according to the present embodiment includes a graphene growth step of growing the graphene layer 120 on the metal catalyst growth substrate 110; Forming an atomic layer 130 by performing an atomic layer deposition process on the graphene layer 120; A transparent conductive layer forming step of forming a transparent conductive layer 140 on the atomic layer 130; Removing a portion of the metal catalyst growth substrate 110 to form a bus electrode 110 ′; And attaching the bus electrode 110 ′ to the flexible substrate 150.

In this embodiment, a method for manufacturing an electrode for a transparent substrate-based electronic device using a part of the graphene growth metal catalyst layer as a bus electrode in a graphene composite electrode in which physical properties of the electrode are supplemented by using a transparent conductive layer and a graphene layer together is disclosed. do.

As shown in FIG. 5, when the metal catalyst growth substrate 110, the graphene layer 120, the atomic layer 130, and the transparent conductive layer 140 are formed, the metal catalyst growth substrate 110 may be used as a transparent substrate of the electrochromic device. The flexibility and transparency of the graphene layer 120 can be used alone as a transparent substrate by using the advantages of thin thickness, but it is difficult to use alone because it is difficult to achieve the required level of conductivity as an electrode. Although the transparent conductive layer 140 exhibits high transparency and conductivity, it is difficult to be implemented as a flexible electrode due to its low flexibility, and the thickness of the electrode is thick to secure high conductivity, and thus, transparency and flexibility are reduced, thereby providing desired quality when used alone. There is a difficulty to achieve.

Electrode of the electrochromic device including a bus electrode according to the present invention includes a transparent conductive layer 140 on the graphene layer 120, to complement the low conductivity of the graphene layer 120, transparent conductive layer 140 ) To increase transparency and ensure electrode flexibility.

In addition, since the transparent conductive layer 140 is formed on the graphene layer 120 and transferred to the flexible substrate, crystallization of the transparent conductive layer 140 through high temperature treatment is possible, thereby achieving high conductivity as well as metal. The graphene layer 120 may prevent the inflow of impurities from the growth substrate 110 between the catalyst growth substrate 110 and the transparent conductive layer 140 to maintain conductivity and transparency of the transparent conductive layer 140.

When the transparent conductive layer 140 is formed, a portion of the metal catalyst growth substrate 110 is removed to form the bus electrode 110 ′. The bus electrode 110 ′ is a path through which voltage or current can be applied to the electrochromic device. The applied voltage or current is applied to the entire surface of the graphene composite electrodes 120 to 140 through the bus electrode, and the voltage or current applied through the graphene layer 120 is applied on the transparent conductive layer 140. That is, the electrical signal for the operation of the transparent substrate-based electronic device is transferred to the upper surface of the transparent conductive layer 140 through the transparent conductive layer 140 through the graphene layer 120 and the graphene layer 120 through the bus electrode. As shown in FIG. 12, the bus electrode connects only the outer portion of the graphene layer 120 and may be formed only in a partial region.

The structure of the bus electrode is not limited to the shape as shown in FIG. 12, but may be formed in various patterns in consideration of the size of the electrode or the element, the distribution of the electric field, and the like.

In the present invention, after forming the graphene layer 120, the atomic layer 130, and the transparent conductive layer 140 instead of separately forming the bus electrode 110 ′ through an additional process, the metal to be removed before transferring to the flexible substrate. Instead of removing all of the catalyst growth substrate 110, a portion of the catalyst growth substrate 110 is left to form the bus electrode 110 ′. This is based on the characteristics of the metal catalyst growth substrate 110 having conductivity. Therefore, since the bus electrode 110 'may be manufactured in a single process in the manufacturing process without separately configuring the bus electrode 110' forming process, the process may be easy and the manufacturing cost may be reduced. In addition, since the graphene layer 120 is grown on the bus electrode, a separate process of attaching the bus electrode 110 ′ on the graphene layer 120 is unnecessary, and thus the formation of an adhesive layer may be omitted.

Removal of the metal catalyst growth substrate 110 for forming the bus electrode 110 ′ uses an etching solution capable of selectively removing the metal catalyst growth substrate 110. The etching solution may be selected according to the type of metal catalyst growth substrate 110. Examples of the etching solution may include hydrogen fluoride (HF), buffered oxide etch (BOE), ferric chloride (FeCl ₃ ) solution, or Ferric nitrate (Fe (NO ₃ ) ₃ ) solution.

The formation of the bus electrode 110 ′ by removing the metal catalyst growth substrate 110 may be performed using a mask M fabricated in a pattern to form the bus electrode 110 ′, or an etching solution and a metal catalyst growth substrate ( In order to limit the contact of the 110, the pattern of the bus electrode 110 ′ may be formed by masking the metal catalyst growth substrate 110 in a desired pattern and then etching the metal catalyst growth substrate 110 (FIG. 11).

The bus electrode 110 ′ is formed with a portion removed as shown in FIG. 12, whereby the graphene layer 120 contacting the metal catalyst growth substrate 110 is exposed to the outside. Thereafter, the flexible substrate 150 is attached to the bus electrode 110 ′ to manufacture a flexible electrode for an electrochromic device. 13 and 14, a portion of the metal catalyst growth substrate 110 is removed to form an empty space 111 in the bus electrode 110 ′, which is formed in a state surrounded by the flexible substrate 150. do.

The transparent substrate based electronic device electrode 100 according to FIG. 13 includes a flexible substrate 150; A bus electrode 110 ′ formed on the flexible substrate 150; A graphene layer 120 on the bus electrode 110 '; An atomic layer 130 formed on the graphene layer 120; And a transparent conductive layer 140 formed on the atomic layer 130.

The flexible substrate 150 that can be used in the present invention is a substrate showing flexibility, for example, poly (methyl methacrylate), PMMA, polyethylene terephthalate (PET), polyethylene or It may include any one of phthalate (polyethylenenaphthalate, PEN), polycarbonate (PC), and polyimide (PI).

15 to 17 are views provided to explain a method of manufacturing an electrochromic device among transparent substrate-based electronic devices according to another embodiment of the present invention. Electrochromic device manufacturing method according to the present embodiment is a graphene growth step of growing a graphene layer 220 on the metal catalyst growth substrate 210; Forming an atomic layer 230 by performing an atomic layer 230 deposition process on the graphene layer 220; Forming a first transparent conductive layer 241 to form a transparent conductive layer on the atomic layer 230; Forming an electrochromic part 260 including an ion storage layer 261, an electrolyte layer 262, and an electrochromic layer 263 on the first transparent conductive layer 241; And a second transparent conductive layer 242 forming a transparent conductive layer on the outermost layer of the electrochromic part 260; Removing a portion of the metal catalyst growth substrate 210 to form a bus electrode 210 '; And bonding the bus electrode 210 'to the flexible substrate 250. Hereinafter, description of the same content as described above will be omitted.

On the first transparent conductive layer 241, an electrochromic part 260 capable of discoloring through voltage application is formed. As described above, the electrochromic portion 260 may be sequentially formed with an ion storage layer 261, an electrolyte layer 262, and an electrochromic layer 263 on the first transparent conductive layer 241. Alternatively, the electrochromic layer 263, the electrolyte layer 262, and the ion storage layer 261 may be formed on the first transparent conductive layer 241.

The ion storage layer 261 is involved in the entry and exit of ions participating in the electrochromic reaction. In the case of the reaction of emitting ions from the electrochromic layer 263 In the case of receiving the ions from the electrochromic layer 263 in the ion storage layer 261 and receiving the ions from the electrochromic layer 263 Provides ions in the ion storage layer 261. The ion storage layer 261 may be an ion storage material or an oxidation / reduction coloring material for storing a plurality of cations such as hydrogen ions or lithium ions or other kinds of ions participating in electrochromic.

In addition to the electrochromic layer 263, the ion storage layer 261 may function as another electrochromic layer for increasing the color change efficiency of the device. The ion storage layer 261 of the electrochromic device may be made of an electrochromic material having a reaction corresponding to the electrochromic layer 263 in a redox reaction. That is, when the electrochromic layer 263 is a reducing discoloring material, the ion storage layer 261 may be an oxidizing discoloring material and vice versa. When the ion storage layer 261 of the electrochromic device is constituted by another electrochromic layer, the color transmittance of the device is reduced to increase the color change efficiency. The electrochromic layer 263 may be formed using an electrochromic material whose color changes according to an electrical signal, and the electrochromic material may be an inorganic material or an organic material.

The electrochromic material used as the ion storage layer 261 and the electrochromic layer 263 may be fluidly selected depending on whether the color change is caused by oxidation or reduction, and the color change with the ion storage layer 261. When the layer 263 is connected to the device, the redox reaction may be selected to correspond. When the electrochromic material used as the ion storage layer 261 and the electrochromic layer 263 is an inorganic material, a transition metal oxide deposited in the form of a thin film may be used. NiO, Cr ₂ O ₃ , MnO ₂ , Rh ₂ At least one selected from O ₃ , CoO _x , Ir (OH) _x , Fe ₂ O ₃ , WO ₃ , ZnO, NbO ₅ , V ₂ O ₅ , TiO ₂ , MoO ₃ , and the like may be used. In addition, the electrochromic material, which is an organic material, is based on a viologen compound, a diphtahlocyanine compound, a tetrathiafulvalene compound, or the like based on polyaniline, polythiophene, or PEDOT (3,4-ethylenedioxythiophene). There is one various high molecular compound. Organic electrochromic materials have a disadvantage in that they can be decomposed by sunlight and shorten their lifespan, but they can be widely used because they can give a desired color when properly mixed.

When the electrochromic portion 260 is formed, a second transparent conductive layer 242 is formed as an electrode facing the first transparent conductive layer 241 (FIG. 15). The second transparent conductive layer 242 may be formed of a transparent, conductive metal oxide or the like that is the same as or similar to the first transparent conductive layer 241.

The electrolyte layer 262 is formed between the ion storage layer 261 and the electrochromic layer 263, and may include a material containing ions involved in the electrochromic reaction. For example, the electrolyte layer 262 is _{Ta 2 O 5, LiClO 4,} LiNbO 3, Li 3 + x PO 4 - x N x (LiPON), LiVO 3 / SiO 2 / Li 4 SiO 4 -Li 3 VO 4 (LVSO), LiPF ₆ , Li ₃ PO ₄ or the like may be formed using at least one. The electrolyte may be a solid electrolyte or a gel electrolyte.

When the electrolyte layer 262 is a solid electrolyte, the electrochromic portion 260 sequentially forms the ion storage layer 261, the electrolyte layer 262, and the electrochromic layer 263 on the first transparent conductive layer 241. It can be formed by laminating.

Unlike the first transparent conductive layer 241, the graphene layer 220 is not formed together on the second transparent conductive layer 242. Accordingly, the second transparent conductive layer 242 may be formed to have a larger thickness than the first transparent conductive layer 241 or a material having higher conductivity as necessary.

When the second transparent conductive layer 242 is formed, since the formation of the graphene layer 220, the first transparent conductive layer 241, the electrochromic part 260, and the second transparent conductive layer 242 is completed, the metal catalyst is grown. A portion of the substrate 210 is removed to form a bus electrode 210 '(FIG. 16). Then, the flexible substrate 250 is attached to the bus electrode 210 '(FIG. 11).

When the electrolyte layer 262 is a gel electrolyte, the forming of the electrochromic portion 260 and the forming of the second transparent conductive layer 242 may include forming an electrochromic layer on the first transparent conductive layer 241. Forming a layer of any one of 263 and the ion storage layer 261; Forming another layer of the electrochromic layer 263 and the ion storage layer 261 on the second transparent conductive layer 242; And a laminating step of applying and laminating the electrolyte layer 262 between the electrochromic layer 263 and the ion storage layer 261.

That is, in the case of using the gel electrolyte, the electrochromic layer, the electrolyte layer, and the ion storage layer are not sequentially formed to form the electrochromic portion, but the ion storage layer is formed on the first transparent conductive layer, and the second transparent conductive layer is formed. After the remaining electrochromic layer is formed on the surface, an electrolyte layer is applied therebetween, and then both are laminated to produce an electrochromic device.

In the present invention, the gel electrolyte is a material containing a polymer in a solvent in which a salt containing ions participating in an electrochromic reaction is dissolved, and may further include additives such as an initiator and a crosslinking agent to be cured by light or heat in a subsequent process. have. The salt in the gel electrolyte are _{LiClO 4, LiPF 6, LiTFSI (} CF 3 SO 2 NLiSO 2 CF 3), LiFSI (F 2 LiNO 4 S 2) Li + commonly used boundaries, such as, but involved in the electrochromic reaction It can be used variously according to the kind of ion. The polymer material used in the gel electrolyte may be a polymer based on polyethylene oxide (PEO), poly (ethylene glycol) (PEG), poly acrylonitrile (PAN), or other types of polymers. As a solvent, an organic solvent that is stable in electrochemical reactions and low in volatility is mainly used. Examples of the solvent include PC (propylene carbonate) and EC (ethylene carbonate).

The material used in the electrolyte layer 262 may be variously selected in connection with the redox reaction occurring in the electrochromic layer 263 and the ion storage layer 261 as well as the above examples, and the electrochromic reaction may be smoothly performed. Various other types of additives may be introduced to make this.

As described above, in the embodiments of the present invention, an electrode for a transparent substrate-based electronic device including a bus electrode may be manufactured using a graphene composite electrode having improved conductivity and flexibility, while maintaining the growth substrate of the graphene layer as it is. By forming a bus electrode using the above, it is possible to obtain a high quality electrochromic device by a simpler method without additional bus electrode configuration step.

As described above, embodiments of the present invention have been described, but those skilled in the art may add, change, delete, or add elements within the scope not departing from the spirit of the present invention described in the claims. The present invention may be modified and changed in various ways, etc., which will also be included within the scope of the present invention.

Claims (16)

1. Graphene layer;

   An atomic layer formed on the graphene layer; And

   Graphene composite electrode comprising a; transparent conductive layer formed on the atomic layer.
2. The method according to claim 1,

   The atomic layer,

   Graphene composite electrode formed by arranging atoms in a defect region existing on the graphene layer.
3. The method according to claim 1,

   The atomic layer is a graphene composite electrode that is a layer of atoms of a metal or metal oxide.
4. A graphene growth step of growing graphene on the metal catalyst growth substrate;

   Forming an atomic layer by performing an atomic layer deposition process on the graphene layer; And

   Graphene composite electrode manufacturing method comprising a; transparent conductive layer forming step of forming a transparent conductive layer on the atomic layer.
5. The method according to claim 4,

   And a metal catalyst growth substrate pretreatment step of performing at least one pretreatment process of a light irradiation process and a heat treatment process on the metal catalyst growth substrate before the graphene growth step.
6. The method according to claim 4,

   The atomic layer is a graphene composite electrode manufacturing method is formed by repeating the atomic layer deposition process a plurality of times.
7. The method according to claim 4,

   The transparent conductive layer forming step,

   Graphene composite electrode manufacturing method that is performed by the deposition process or the coating process.
8. The method according to claim 4,

   Removing the metal catalyst growth substrate; And

   Attaching a flexible substrate on the graphene layer; Graphene composite electrode manufacturing method further comprising.
9. A graphene layer growth step of growing graphene on the metal catalyst growth substrate;

   Forming an atomic layer by performing an atomic layer deposition process on the graphene layer;

   Forming a transparent conductive layer on the atomic layer;

   Removing a portion of the metal catalyst growth substrate to form a bus electrode; And

   And attaching the bus electrode to the flexible substrate.
10. The method according to claim 9,

    Forming the atomic layer,

    Electrode manufacturing method for a transparent substrate-based electronic device that is performed by arranging atoms in the defect region existing on the graphene layer.
11. The method according to claim 9,

    The metal catalyst growth substrate is Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, Zr, brass, bronze, white copper, Electrode manufacturing method for a transparent substrate-based electronic device comprising at least one metal or an alloy thereof selected from the group consisting of stainless steel and Ge.
12. The method according to claim 9,

    Forming the bus electrode,

    Method of manufacturing an electrode for a transparent substrate-based electronic device that is performed by removing a portion of the metal catalyst growth substrate to expose the graphene layer.
13. The method according to claim 9,

    Forming the bus electrode,

    Placing a mask on the metal catalyst growth substrate; And

    Etching the metal catalyst growth substrate; Electrode manufacturing method for a transparent substrate based electronic device comprising a.
14. The method according to claim 9,

    The flexible substrate may be made of polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polyethylenenaphthalate (PEN), polycarbonate (PC) and polyimide (polyimide). The electrode manufacturing method for a transparent substrate-based electronic device comprising any one of PI).
15. A graphene growth step of growing graphene on the metal catalyst growth substrate;

    Forming an atomic layer by performing an atomic layer deposition process on the graphene layer;

    A first transparent conductive layer forming step of forming a transparent conductive layer on the atomic layer;

    Forming an electrochromic part including an electrochromic layer, an electrolyte layer, and an ion storage layer on the first transparent conductive layer;

    A second transparent conductive layer forming step of forming a transparent conductive layer on the outermost layer of the electrochromic part;

    Removing a portion of the metal catalyst growth substrate to form a bus electrode; And

    Attaching the bus electrode to a flexible substrate.
16. Flexible substrate;

    A bus electrode formed on the flexible substrate;

    A graphene layer formed on the electrical connection portion;

    An atomic layer formed on the graphene layer; And

    Transparent substrate-based electronic device electrode comprising a; transparent conductive layer formed on the atomic layer.

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