KR20140088850A - Vo2 laminate with functionalized graphene for thermo-chromic smart window - Google Patents

Abstract

Disclosed is a VO_2 laminate based on graphene for a smart window. The VO_2 laminate based on graphene for a smart window according to an embodiment of the present invention comprises: a functionalized graphene layer including one or more layers; and a vanadium dioxide (VO_2) layer formed on the upper surface of the functionalized graphene layer (110). The present invention can improve the light transmittance of the VO_2 laminate by using the graphene layer, which has been functionalized by doping and intentional and structural defect generation, as the base of the vanadium dioxide layer.

Description

{VO2 LAMINATE WITH FUNCTIONALIZED GRAPHENE FOR THERMO-CHROMIC SMART WINDOW} <br> <br> <br> Patents - stay tuned to the technology Functionalized graphene-based VO2 laminate for thermochromic smart windows [

The present invention relates to VO ₂ (vanadium dioxide) laminates, and more particularly to a graphene-based VO ₂ laminate that is functionalized for smart windows that can be transferred or attached to a smart window.

It has been widely known that energy loss in buildings is the most common through window, and various methods have been tried to prevent such energy loss.

Recently, thermochromic glasses which control the energy inflow through the infrared ray transmittance by coating a thermochromic material, which is a characteristic of changing the color of a material by heat, are being studied. Such a thermochromic glass is attracting interest in the development of a so-called 'smart window' capable of controlling light transmittance and reflectance freely.

The thermochromic material has a characteristic that light transmittance and reflectivity vary greatly based on the phase-change temperature, and a typical example of the thermochromic material is vanadium dioxide (VO ₂ , vanadium dioxide). Vanadium dioxide has metal-insulator transition (MIT) characteristics at around 340K (68 ° C). That is, the vanadium dioxide exists in a metal form at a phase transition temperature of 68 ° C or higher to shield infrared rays, and when it is less than 68 ° C, it exists in an insulator form to transmit infrared rays. Accordingly, various attempts have been made to apply vanadium dioxide to smart window development.

Korean Patent Laid-Open Publication No. 2012-0127043 discloses an energy-saving window for coating a substrate with a thermochromic thin film and a transparent conductive film to improve the cooling and heating efficiency of a building. The window is formed on a substrate and on the upper surface of the substrate. Chromium thin film in which the transmittance of the vanadium dioxide is controlled. However, in the case where only vanadium dioxide is coated on the glass, the absolute value of the light transmittance is relatively low, . Further, in order to utilize the thermochromic characteristic of vanadium dioxide in a smart window, the phase transition temperature should be reduced to about room temperature, and it is necessary to control the phase transition temperature of vanadium dioxide. Accordingly, a method for improving light transmittance in a smart window and lowering the phase transition temperature of vanadium dioxide has been sought.

No. 10-2011-0080007 filed by the present applicant discloses a VO ₂ laminate for smart windows based on a graphene layer but there is a difficulty in controlling the grain size of the graphene, The size of the graphene layer decreases the transmittance of light.

In order to solve the above problems, the inventors of the present invention have proposed a method of forming a graphene layer by doping a graphene layer with a dopant, or by applying oxygen plasma, UV irradiation, chemical treatment, or the like to artificially generate a structural defect in the graphene layer, Functionalized graphene, and functionalized graphene can control the grain size uniformly to improve the light transmittance, thereby completing the present invention.

In embodiments of the present invention, functionalization is added to graphene by pretreating the graphene with doping, defect generation, or the like to improve the light transmittance by using the functionalized graphene layer as the base of the vanadium dioxide layer, We will provide a functionalized graphene-based VO ₂ laminate for smart windows with lower phase transition temperatures.

The laminate for a thermochromic smart window according to the present invention comprises a first step of forming a graphene layer on a first substrate, A second step of functionalizing the graphene layer formed in the first step to form a functionalized graphene layer; A third step of depositing vanadium dioxide (VO2) on the functionalized graphene layer to form a vanadium dioxide layer; A fourth step of laminating the second substrate to form a laminate including the first substrate-functionalized graphene layer-vanadium dioxide layer-second substrate; And a fifth step of removing the first base material from the formed laminate by using an etching method and simultaneously transferring the functionalized graphene layer onto the second base material. (However, if direct transfer is used, it is possible to manufacture film for thermochromic smart window in step 4, and step 5 can be omitted)

In the first step, the graphene forming the graphene layer is produced by peeling graphite or by a conventional CVD method.

The graphene layer functionalized in the second step is formed by doping with a dopant selected from SiHN ₄ , NH ₃ , N ₂ , XeF ₂ and B ₂ H ₆ in addition to the hydro-carbon gas during the CVD process, The graphene film is produced by artificially generating defects in the graphene structure by at least one of plasma treatment, UV irradiation, and wet chemical treatment.

The protective layer may further include at least one material selected from the group consisting of polymethylnathacrylate (PMMA), polyvinylidene fluoride (PVDF), polystyrene (PS) -co-PMMA-co- ), ER (electroresist), SiOx, TiOx, TiOx-Ag, ITO, FTO, or AlOx.

The functionalized graphene layer may further include a flexible substrate such as an adhesive tape to be transferred or adhered, a paste, an epoxy resin, a thinning tape, a heat-peelable tape, or a water-soluble tape.

The invention VO ₂ by using a functionalized yes pin layer by doping, artificially structural defects created in the base of the vanadium dioxide layer The light transmittance of the laminate can be improved.

By using the functionalized graphene layer as the base of the vanadium dioxide layer, the phase transition temperature of the vanadium dioxide layer can be relatively lowered, and by controlling the size of the crystal structure uniformly, the surface roughness can be lowered to have a smooth surface.

In addition, since functionalized graphene layers can be transferred to various substrates, it is possible to simplify the related processes in production of VO ₂ films for smart windows, and to increase the size thereof, so that the VO ₂ films for thermochromic smart windows Mass production is possible.

1 is a perspective view schematically illustrating a functionalized graphene-based VO ₂ laminate for a smart window according to an embodiment of the present invention.
2 is a flowchart of a functionalized graphene-based VO ₂ laminate manufacturing method for a thermochromic smart window according to an embodiment of the present invention.
FIG. 3 is a graph showing the relationship between graphene and NH ₃ , N ₂ , CH ₄ , and H ₂ (chemical vapor deposition) (Doping) of the Raman spectroscopic analysis.
FIG. 4 is a graph showing the relationship between graphene and NH ₃ , N ₂ , CH ₄ , and H ₂ (chemical vapor deposition) Is a TEM image when a gas such as hydrogen is injected (Doping).
FIG. 5 is a Raman spectroscopic analysis result of inducing nitrogen substitution according to process parameters (plasma power, reactive time, gas flow) using a plasma induction apparatus (Reactive Ion Etching Plasma) and changing the doping time.
Figure 6 (a) to Fig. 6 (f) is VO ₂ Sectional view of the layered product 100. Fig.

Hereinafter, embodiments of the present invention will be described in detail. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted so as to avoid obscuring the subject matter of the present invention.

The terms "about "," substantially ", etc. used to the extent that they are used herein are intended to be taken to mean an approximation of, or approximation to, the numerical values of manufacturing and material tolerances inherent in the meanings mentioned, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

It is noted that each layer of the graphene-based VO ₂ laminate for smart windows described herein is only based on the attached drawings. That is, not only the case where only the layer referred to in this specification is made, but also the case where another layer intervenes or exists between the layers can be included in the scope of the present invention.

It is also to be understood that the expressions &quot; above &quot;, &quot; above &quot;, or &quot; above &quot; in this specification are intended to refer to the relative positional concept relative to the attached drawings, (Particularly surfaces having a three-dimensional shape), although other layers or components may be present or present, as well as those present in the upper layer in relation to the layer referred to, It is possible to include the case where the cover is not completely covered. Likewise, the expression &quot; lower, &quot; &quot; under, &quot; or &quot; under &quot; may also be understood as a relative concept of the position between a particular layer (component)

Functionalization of functionalized graphene or functionalized graphene layer herein means that the dopant is displaced by atoms of the graphene structure or artificially created defects in the graphene structure by doping.

FIG. 1 is a perspective view schematically illustrating a functionalized graphene-based VO ₂ laminate 100 (hereinafter, referred to as a VO ₂ laminate) for a smart window according to an embodiment of the present invention.

Referring to Figure 1, VO ₂ It may _{comprise; (VO 2, Vanadium Dioxide 120} ) stack 100 is functionalized graphene (Graphene) layer 110, a pinned layer Yes 110 vanadium dioxide layer formed on the top surface.

The functionalized graphene layer 110 is formed with VO ₂ layer 120, By forming the layered structure 100, not only the light transmittance of the VO ₂ stacked body 100 is enhanced, but also the phase transition temperature of the vanadium dioxide layer 120 can be relatively lowered.

The functionalized graphene layer 110 may also serve to protect the vanadium dioxide layer 120 during processing. The functionalized graphene layer 110 may serve as a seed base when forming the vanadium dioxide layer 120 and may have a function of providing a smooth surface by lowering the surface roughness of the VO ₂ layered body 100 can do.

The refractive index of unfunctionalized graphene is 2.35 to 2.7, while the refractive index of functionalized graphene is 1.8, which is a relatively low value. When a laminate is formed of vanadium dioxide having a refractive index of 2.4 to 2.7 and a functionalized graphene layer, Control (when high-deflection / low-refractive-index laminated optical design) is possible.

The graphene for forming the functionalized graphene layer 110 is formed by forming a layer or a sheet form of graphene in which a plurality of carbon atoms are covalently linked to each other to form polycyclic aromatic molecules. The carbon atoms linked by the covalent bond form a 6-membered ring as shown in FIG. 1 as the basic repeating unit, but are not limited thereto. That is, the carbon atoms may be formed of a 5-membered ring, a 7-membered ring, or the like.

The functionalized graphene layer 110 may be formed of a single layer, but is not limited thereto and may be formed of a plurality of layers. For example, the functionalized graphene layer 110 may be formed of more than 50 layers. For multiple layers, graphene can be prepared by CVD synthesis, but after formation of single-layer graphene through CVD, graphene oxide (GO) or reduced graphene oxide made from natural graphene graphene oxide (R-GO) may be coated to form a functionalized graphene layer.

The functionalized graphene layer 110 may be formed in a large area, and may be formed to have a length of, for example, from about 1 mm to 1000 m in the transverse direction or the longitudinal direction. A method of forming the functionalized graphene layer 110 will be described later with reference to other drawings.

The vanadium dioxide layer 120 is formed on the upper surface of the functionalized graphene layer 110 and includes vanadium dioxide (VO ₂ ). The vanadium dioxide has a metal-insulator transition (MIT) characteristic from an insulator to a metal at about 340K (68 DEG C). Accordingly, the vanadium dioxide is present in a metal form at a phase transition temperature of 68 캜 or higher and shields infrared rays, and when it is less than 68 캜, it is present in an insulator form to transmit infrared rays.

Since the vanadium dioxide corresponds to a substance having a thermochromic characteristic, the shielding function of the smart window can be controlled by using the MIT characteristic and the thermochromic characteristic of the vanadium dioxide.

The vanadium dioxide layer 120 may be formed on the upper surface of the functionalized graphene layer 110 by thermal deposition, chemical vapor deposition (CVD), sputtering, -gel), but the present invention is not limited thereto.

On the other hand, VO ₂ The laminate 100 may further include a flexible substrate P to which the functionalized graphene layer 110 is transferred or adhered.

The functionalized graphene is characterized in that it can be easily transferred to various substrates. Thus, functionalized graphene-based VO ₂ When producing the stack 100 to the film to form it is possible to easily prepared by transferring the various flexible substrate (P), as well as to further simplify the associated process large area VO ₂ Mass production of laminated films is possible.

The flexible substrate P has flexibility and may additionally have transparency. The flexible substrate P may be a tape or a thin film including a heat peelable polymer, but is not limited thereto.

For example, the flexible substrate P may be formed of a material such as polydimethylsiloxane (PDMS), a polyurethane film, a water based adhesive, a water soluble adhesive, a vinyl acetate emulsion adhesive, a hot melt adhesive, an adhesive for light curing (UV, visible light, Polyvinyl alcohol (PBI), polyimide (PBI), silicone / imide, bismaleimide (BMI), modified epoxy resin, PVA (polyvinylalcohol) tape / thin film, general adhesive tape and the like.

In addition, an adhesive layer (not shown) may be additionally formed on the flexible substrate P to facilitate adhesion or separation of the functionalized graphene layer 110. The adhesive layer may include an adhesive tape, a paste, an epoxy resin, a weathering tape, a heat-peelable tape, or a water-soluble tape.

In accordance with one embodiment of the present invention, VO ₂ The layered structure 100 may further include a protective layer (not shown) formed on the vanadium dioxide layer 120. The protective layer functions to protect the vanadium dioxide layer 120. For example, the protective layer protects the vanadium dioxide layer 120, and may include, for example, polymethyl methacrylate (PMMA), polystyrene (co) ), SiOx, TiOx, TiOx-Ag, ITO, FTO, or AlOx.

Hereinafter, a graphene-based VO ₂ laminate (hereinafter, referred to as VO ₂ laminate) for a thermochromic smart window according to an embodiment of the present invention will be described.

Figure 2 is a thermopile electrochromic smart window functionalized graphene-based for VO _2, according to one embodiment of the present invention And a method of manufacturing a laminate.

Referring to FIG. 2, a graphite-based VO ₂ for thermochromic smart window according to an embodiment of the present invention A method of producing a laminate (hereinafter referred to as VO ₂ A first step of forming a graphene layer on the first base material; A second step (S110) of functionalizing the formed graphene layer to form a functionalized graphene layer; A third step (S120) of depositing vanadium dioxide (VO ₂ ) on the functionalized graphene layer to form a vanadium dioxide layer; A fourth step (S130) of laminating the second substrate to form a laminate including the first substrate-functionalized graphene layer-vanadium dioxide layer-second substrate; And a fifth step (S140) of removing the first base material from the formed laminate by using an etching method and simultaneously transferring the functionalized graphene layer onto the second base material. Hereinafter, each step will be described.

1. On the substrate Graphene layer  Forming step

The graphene layer formed on the first base material may be formed of graphene obtained by peeling graphite, or may be graphene produced by a CVD method.

The method of peeling from the graphite is carried out by a physical peeling method which is peeled off by a mechanical method and a chemical peeling method by an oxidation / reduction reaction.

Conventional chemical vapor deposition methods can be used as a method of growing graphene. Examples of the chemical vapor deposition include chemical vapor deposition (RTCVD), inductively coupled plasma chemical vapor deposition (CVD), low pressure chemical vapor deposition (LPCVD), atmospheric pressure chemical vapor deposition (APCVD), metal organic chemical vapor deposition ) Or chemical vapor deposition (PECVD).

In order to grow graphene on the first substrate to form a graphene layer, the first substrate is placed in a furnace, and a reaction gas containing a carbon source is supplied and heat-treated at a normal pressure (300 to 2000 ° C) The pin can be grown. Examples of the carbon source include carbon monoxide, carbon dioxide, methane, ethane, ethylene, ethanol, acetylene, propane, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene and toluene.

The first substrate serves as a seed layer for growing the graphene, and is not limited to a specific material. For example, the first substrate may be made of at least one selected from the group consisting of silicon, Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, Bronze, white copper, stainless steel, and Ge.

In addition, the first substrate may include a catalyst layer to facilitate the growth of the graphene. The catalyst layer is not limited to a specific material, and may be formed of the same or different material as the first base material. The thickness of the catalyst layer is not limited, and may be a thin film or a thick film.

Another method of growing graphene on the first substrate to form a graphene layer uses a solid polymer as a source for forming the graphene layer. That is, a polymer layer including a carbon source is coated on the substrate.

The substrate may have transparency, flexibility, stretchability, or a combination thereof. The substrate may be a non-catalytic substrate, for example, a polyethyleneterephthalate (PET) substrate, a polyethersulfone (PES) substrate, a polyimide (PI) substrate, a boron nitride (BN) / Si0 may be at least one selected from the substrate _2, Si ₃ N ₄ substrate, a sapphire substrate, a quartz (Quartz) substrate and a glass substrate.

On the other hand, the substrate may be a metal substrate, or may further include a metal base layer (not shown) formed between the substrate and the polymer layer. The metal substrate layer may be formed on the substrate using a conventional deposition or coating method.

In this case, the metal in the metal substrate or the metal base layer may be, for example, silicon, Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, One or more metals or alloys selected from the group consisting of W, U, V, Zr, brass, bronze, white copper, stainless steel and Ge.

The shape of the substrate is not limited. For example, the substrate may have the form of a sheet, a rod, or a wire.

The polymer layer containing a carbon source may serve as a seed layer for graphene synthesis, and may include, for example, polymethacrylate (PMMA), polystyrene, acrylonitrile butadiene styrene (ABS) A self-assembled monolayer (SAM), and polyimide.

2. Graphene layer  Steps to functionalize

(1) Doping of the graphene layer

The grain size of the graphene layer is made uniform through chemical doping of graphene to improve the light transmittance and control the refractive index.

The functionalized graphene layer may be formed by doping with a dopant selected from SiHN ₄ , NH ₃ , N ₂ , XeF ₂ and B ₂ H ₆ in addition to a hydro-carbon gas in a CVD process, By artificially generating defects in the graphene structure by at least one of the treatment, the UV irradiation, and the wet chemical treatment.

The dopant used for functionalized graphene fabrication may include, but is not limited to, an organic dopant, an inorganic dopant, or a combination thereof.

When the dopant vapor is used in the doping process, the dopant vapor may be formed in the container containing the doping solution by a heating device for vaporizing the doping solution. When a doping solution is used in the doping process, a container containing the doping solution may be provided with a height adjusting device for adjusting the gap between the graphene film and the solution.

The characteristics of the doped graphene film formed by the doping process can be controlled by varying the dopant and / or the doping time in the doping process. For example, the refractive index and transparency of the doped and / or doped graphene films can be controlled by varying the doping time and / or the doping time.

(2) Defect formation of graphene layer

Graphene can be functionalized by artificially forming defects on the graphene surface by treating the graphene surface with an oxygen plasma. I.e., structural defects in the graphene to control the electrical properties, light transmittance and refractive index of the graphene.

Structural defects of graphene are characterized by the heating of graphene, contact with gases chemically reacting with graphene, UV irradiation, application of ultrasonic waves, or contact with oxygen plasma, Not only the electrical characteristics of the fin are controlled, but also the crystal growth can be controlled at the time of graphen generation, so that the grain size can be controlled to be uniform.

To generate defects in the graphene layer, an oxygen plasma (plasma finish GmbH V6-G) was produced at a plasma power of 5 to 500 W, an oxygen flow rate of 1 to 100 sccm, and a pressure of 100 Pa to bring the graphene layer and the oxygen plasma into contact.

And UV irradiation can control functional groups bound to graphene edge and organic matter remaining on graphene surface. The UV wavelength used is Hg lamp (LH-arc, Lichtzen, with an output of 20mWcm- ² , with a majority of the emitted light at a wavelength of 254nm and approximately 10% Do not exceed 30 minutes.

Finally, the wet chemical treatment can induce defects on the graphene surface or edge using chemicals consisting of hydrochloric acid, nitric acid, sulfuric acid, hydrogen peroxide, hydrofluoric acid, and combinations thereof. The chemical (liquid) The defect rate can be controlled by increasing the degree.

① Graphene functionalization through nitrogen substitution during CVD process

FIGS. 3 and 4 show graphs of NH ₃ , N ₂ , CH ₄ , and H _{2 (} graphite) synthesized using a CVD (Chemical Vapor Deposition) (Doping) of a gas such as nitrogen gas.

Raman spectroscopy analysis reveals differences in electron structure and binding energy, such as when the nitrogen atom is replaced with a carbon atom of the graphene (graphitic) and when it is doped to the edge of the broken structure (pyridinic). Analysis of Raman Peak reveals that the D and G 'intensity values of the graph are increased by doping from the pristine graphene to the graphene of the N-type electron structure, and the 2D intensity reduction and the FWHM (full width half maximum) value increase Respectively.

(2) Graphene functionalization through plasma-assisted CVD graphene and graphite (HOPG) nitrogen substitution

CVD graphene (PDMS transfer method) and HOPG (Highly Ordered Pyrolytic Graphite) graphene were fabricated on SiO ₂ / Si substrate to induce nitrogen substitution of graphene. 5, the prepared graphene samples were subjected to nitrogen substitution according to process parameters (plasma power, reactive time, and gas flow) using Reactive Ion Etching Plasma (RIE Plasma) and the doping time was changed. The Raman spectroscopic analysis shown in FIG. 5 confirms that the N-type electron structure is doped with increasing time. However, at 10 seconds, the 2D peak disappears and the graphene is damaged due to the influence of plasma for a long time. The G 'peak, which appears next to G peak as it is doped, represents the graphene surface and edge defects through the plasma process.

3. The laminate  Forming step

Figure 6 (a) to Fig. 6 (f) is VO ₂ Sectional view of the layered product 100. Fig. VO ₂ The laminate 100 can be manufactured through one continuous process by a reel to reel process or the like.

The metal base (m) functions as a base for growing graphene, and is not limited to a specific material. For example, the metal base (m) may be at least one selected from the group consisting of silicon, Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, Brass, bronze, white copper, stainless steel and Ge.

Further, the metal base (m) may include a catalyst layer 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 base (m). The thickness of the catalyst layer is not limited, and may be a thin film or a thick film.

As shown in FIG. 6 (b), the metal base m has a graphene layer 109 formed thereon. At this time, the graphene layer 109 may be grown on the substrate surface by a conventional CVD method, or the graphene layer 109 obtained by peeling the graphite may be laminated to form the graphene layer 109. Further, it may further include a step of pretreating the metal substrate (m) through hydrogen gas or the like before the metal substrate (m) forms graphene.

6 (c) shows a state in which a functionalized graphene layer 110 is formed by doping or artificial defects in the graphene layer 109 formed on the substrate surface.

6 (d), the vanadium dioxide layer 120 may be formed by being transferred or applied onto the graphene layer 110. Alternatively, the vanadium dioxide layer 120 may be formed on the metal substrate m having the graphene layer 110 formed thereon by thermal deposition, CVD (Chemical Vapor Deposition), sputtering, e-beam, or the like have.

In addition, the VO ₂ laminate can be removed by a roll-to-roll apparatus or the like including a chamber containing an etching solution, wherein the etching solution is added to the kind of the metal substrate (m) Can be selected correspondingly. Examples of the etching solution include hydrogen fluoride (HF), buffered oxide etch (BOE), ferric chloride (FeCl ₃ ) solution, ferric nitrate (Fe (NO ₃ ) ₃ ) solution, sulfuric acid and water, But is not limited thereto.

Next, as shown in Fig. 6 (f), a protective layer is formed on the laminate from which the metal base m has been removed. The protective layer 130 functions to externally protect the VO ₂ stack 100 and the functionalized graphene layer 110. The protective layer 140 may be formed of, for example, polyethyleneterephthalate (PET), poly methyl methacrylate (PMMA), polyvinylidenefluoride (PVDF) copolymer, polystyrene-co-PMMA-co-PS, photoresist, ), SiOx, TiOx, TiOx-Ag, ITO, FTO, or AlOx, but the present invention is not limited thereto.

The protective layer 140 may be formed by transferring or applying the functionalized graphene layer 110 under the functional layer 140. Alternatively, the protective layer 140 may be formed by thermal deposition, CVD (Chemical Vapor Deposition), sputtering, e-beam, or the like.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention as set forth in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

100: Functionalized graphene-based VO ₂ laminate for smart windows
109: graphene layer 110: functionalized graphene layer
120: vanadium dioxide layer 130: protective layer
P: flexible substrate m: metal substrate

Claims (9)

A graphene layer having at least one or more layers:
And a layer of vanadium dioxide (VO ₂ ) formed on one side of the graphene layer.
The method of claim 1, wherein the graphene layer is a graphene layer doped with a dopant selected from SiHN ₄ , NH ₃ , N ₂ , XeF ₂ , and B ₂ H ₆ in addition to a hydro-carbon gas during CVD A laminate for a thermochromic smart window characterized by.
The thermochromic smart window laminate according to claim 1, wherein the graphene layer is a functionalized graphene layer by generating defects in the graphene structure by at least one of plasma treatment, UV irradiation, and wet chemical treatment .
The method as claimed in any one of claims 1 to 3, further comprising a protective layer formed on the vanadium dioxide layer, wherein the protective layer is made of PMMA (polymethylnaphthacrylate), PVDF (polyvinylidene fluoride), PS (polystyrene) A laminate for a thermochromic smart window which is at least one selected from PMMA-co-PS, PR (photoresist), ER (electroresist), SiOx, TiOx, TiOx-Ag, ITO, FTO or AlOx.
The laminate for a thermochromic smart window according to any one of claims 1 to 3, further comprising a flexible substrate to which the graphene layer is transferred or adhered.
The laminate for a thermochromic smart window according to claim 4, further comprising a flexible substrate to which the graphene layer is transferred or adhered.
The laminate for a thermochromic smart window according to claim 5, further comprising a flexible substrate onto which the graphene layer is transferred or adhered.
The laminate for a thermochromic smart window according to claim 6, wherein the flexible substrate is an adhesive tape, a paste, an epoxy resin, a thinning tape, a heat-peelable tape, or a water-soluble tape.
8. The laminate for a thermochromic smart window according to claim 7, wherein the flexible substrate is an adhesive tape, a paste, an epoxy resin, a lightening tape, a heat-peeling tape or a water-soluble tape.

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