JP2013213944A - Method for forming electrochromic thin film, and method for manufacturing electrochromic element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming an electrochromic thin film capable of producing a nickel oxyhydroxide thin film which can use a nearly neutral aqueous solution electrolyte or an acidic aqueous solution electrolyte, and a method for manufacturing an electrochromic element.SOLUTION: A method for forming an electrochromic thin film includes the steps of: forming a nickel oxyhydroxide thin film by reactive sputtering using steam; and heat-treating the formed nickel oxyhydroxide thin film in the atmosphere at a temperature of 200 to 300°C.

Description

  The present invention relates to a method for forming an electrochromic thin film exhibiting electrochromic characteristics and a method for manufacturing an electrochromic device using the electrochromic thin film.

  The electrochromic property is a property that causes a reversible optical property change by applying electric energy. Generally, an electrochromic property is caused by an electrochemical redox reaction caused by a change in a flowing current (amount of electricity). It shows the property that the tone and color of the substance change reversibly.

  As a conventional technique for forming an electrochromic thin film exhibiting such electrochromic characteristics, Non-Patent Documents 1 and 2 by the inventors of the present application are close to an amorphous structure by using a sputtering method using water vapor as a reaction gas. The creation of low density nickel oxyhydroxide thin films is described. According to such a method, a uniform hydroxide thin film having a large area can be easily produced. Moreover, it is known that this type of nickel hydroxide thin film exhibits superior electrochromic characteristics as compared with a nickel oxide thin film prepared using oxygen gas as a reaction gas. For example, the current accompanying the oxidation-reduction reaction in the aqueous potassium hydroxide electrolyte increases, and a large transmittance change of 40% or more can be obtained, which is useful for application to light control glass, for example.

Ni Oxyhydroxide Thin Films Prepared by Reactive Sputtering Using O2 + H2O Mixed Gas, Hideaki Ueta et al, Jpn. J. Appl. Phys., Vol. 48 (2009), 015501 Effects of Sputtering Gas Pressure on Electrochromic Properties of Ni Oxyhydroxide Thin Films Prepared by Reactive Sputtering in H2O Atmosphere, Yoshio Abe et al, Jpn. J. Appl. Phys., Vol. 49 (2010), 115802

  However, the nickel oxyhydroxide thin film prepared by the conventional method as described above can repeat a stable oxidation-reduction reaction in a strongly basic potassium hydroxide aqueous solution electrolyte, but in an aqueous solution electrolyte close to neutrality. When it deteriorates rapidly and repeats the oxidation-reduction reaction for about 100 cycles, it hardly shows a color change.

  As known in the art, a complementary electrochromic device with high coloring efficiency can be obtained by combining an oxidation coloring electrochromic material such as nickel oxyhydroxide with a reduction coloring electrochromic material such as tungsten oxide. Can be configured. However, since nickel oxyhydroxide prepared by the prior art dissolves in an acidic aqueous solution, tungsten oxide dissolves in a neutral to alkaline aqueous solution, so an aqueous electrolyte with high conductivity cannot be used. It was. For this reason, an organic electrolyte or a solid electrolyte having a low ion conductivity is used, which causes a reduction in response speed.

  Accordingly, an object of the present invention is to provide a method for forming an electrochromic thin film and a method for manufacturing an electrochromic device capable of producing a nickel oxyhydroxide thin film capable of using an aqueous electrolyte close to neutrality.

  Another object of the present invention is to provide a method for forming an electrochromic thin film and a method for manufacturing an electrochromic device capable of producing a nickel oxyhydroxide thin film that can be used in an acidic aqueous electrolyte.

  According to the present invention, an electrochromic thin film is formed by forming a nickel oxyhydroxide thin film by reactive sputtering using water vapor and heat-treating the formed nickel oxyhydroxide thin film at a temperature of 200 to 300 ° C. in the atmosphere. A method is provided.

  Since the nickel oxyhydroxide thin film formed by reactive sputtering using water vapor is heat-treated in the atmosphere at a temperature of 200 to 300 ° C., the crystallinity is improved while maintaining the hydroxide state. Resistance to aqueous electrolyte is improved. An aqueous electrolyte having a pH close to pH = 4, which was impossible with the prior art, can be used, and an acidic aqueous electrolyte can also be used.

  The heat treatment time is preferably 1 to 3 hours. In this way, a nickel oxyhydroxide thin film having stable performance can be obtained.

  According to the present invention, an electrochromic device manufacturing method includes a first transparent electrode forming step of forming a first transparent electrode on a surface of a first transparent substrate, and a surface of the formed first transparent electrode. A first electrochromic thin film forming step of forming a first electrochromic thin film, a second transparent electrode forming step of forming a second transparent electrode on the surface of the second transparent substrate, and a formed second A counter electrode film forming step of forming a counter electrode film on the surface of the transparent electrode, a first transparent substrate on which the first transparent electrode and the first electrochromic layer are formed, a second transparent electrode and a counter electrode film In the assembly process of laminating the formed second transparent substrate with the electrolyte layer interposed, and in the first electrochromic thin film forming process, the nickel oxyhydroxide thin film is formed by reactive sputtering using water vapor. And, the nickel oxyhydroxide film was the formation to heat treatment at a temperature of 200 to 300 [° C. in air.

  Thereby, the aqueous solution electrolyte or acidic aqueous solution electrolyte of pH = 4 close | similar to neutrality can be used for an electrochromic element. Compared to conventional organic electrolytes and solid electrolytes, the ionic conductivity is high, so that a high-speed response electrochromic device can be realized.

  A spacer forming step of forming a spacer on the outer periphery of the surface of the first electrochromic layer formed on the first transparent substrate or on the outer periphery of the surface of the counter electrode film formed on the second transparent substrate; and a first transparent electrode The first transparent substrate on which the first electrochromic layer is formed and the second transparent substrate on which the second transparent electrode and the counter electrode film are bonded to each other with the spacer interposed therebetween. It is preferable to further include an electrolyte injection step of injecting an electrolyte into the space formed by the above. Thus, the liquid electrolyte can be easily enclosed.

In the counter electrode film forming step, it is preferable to form a CeO ₂ film having a film thickness of 100 nm to 1 μm by using a sputtering method. Thus, a basic electrochromic element can be obtained.

In the counter electrode film forming step, it is preferable to form a WO ₃ film having a thickness of 100 nm to 1 μm by using a sputtering method. In this way, a complementary electrochromic element is obtained.

In the electrolyte injection step, it is preferable to use a mixed aqueous electrolyte of 5 × 10 ⁻⁵ mol / L sulfuric acid and 1 mol / L KCl. Thus, since the aqueous electrolyte is close to neutral pH = 4, even when an accident such as glass breakage occurs due to mechanical impact when used in a large-area light control glass using an electrochromic device. For example, even if the electrolyte adheres to the skin or eyes, it is relatively safe.

  According to the present invention, the nickel oxyhydroxide thin film formed by reactive sputtering using water vapor is heat-treated in the atmosphere at a temperature of 200 to 300 ° C., thereby improving the crystallinity while maintaining the hydroxide state. Therefore, the resistance of the membrane to the aqueous electrolyte is improved. An aqueous electrolyte having a pH close to pH = 4, which was impossible with the prior art, can be used, and an acidic aqueous electrolyte can also be used.

  For the electrochromic device, an aqueous electrolyte or an acidic aqueous electrolyte with pH = 4 close to neutrality can be used. Compared to conventional organic electrolytes and solid electrolytes, the ionic conductivity is high, so that a high-speed response electrochromic device can be realized.

It is a flowchart which shows the formation method of an electrochromic thin film roughly. It is a figure which shows the infrared absorption spectrum of the electrochromic thin film formed by changing heat processing temperature. It is a figure which shows the X-ray-diffraction pattern of the electrochromic thin film formed by changing heat processing temperature. It is a figure which shows the cycle dependence of the transmittance | permeability change of the element using the electrochromic thin film formed by changing heat processing temperature. It is a figure which shows the change by the heat processing temperature of the optical density change of the element using an electrochromic thin film. It is sectional drawing which shows the structure of a basic electrochromic element roughly. It is a flowchart which shows the manufacturing method of a basic electrochromic element roughly. It is sectional drawing which shows schematically the structure of a complementary electrochromic element. It is a flowchart which shows the manufacturing method of a complementary electrochromic element roughly.

  FIG. 1 shows the main steps of a method for forming an electrochromic thin film according to an embodiment of the present invention. FIG. 2 shows an infrared absorption spectrum of an electrochromic thin film formed by changing the heat treatment temperature, and FIG. 3 shows an X-ray diffraction pattern of the electrochromic thin film formed by changing the heat treatment temperature. Shows the cycle dependence of the transmittance change of the device using the electrochromic thin film formed by changing the heat treatment temperature, and FIG. 5 shows the change of the optical density change of the device using the electrochromic thin film due to the heat treatment temperature. ing.

First, the formation process of the electrochromic thin film in this embodiment is demonstrated. As shown in FIG. 1, a reactive sputtering method using water vapor (H ₂ O) as a reactive gas was used to form the electrochromic thin film.

The thin film forming process will be specifically described. First, for example, a quartz glass substrate or a silicon substrate is placed on a substrate holder in a film forming chamber of an RF magnetron sputtering apparatus (step S1). Next, a nickel (Ni) metal target is placed on the cathode in the film forming chamber (step S2). Next, water vapor (H ₂ O) is circulated in the film forming chamber as a reaction gas (step S3). In this state, high frequency power is applied, and a nickel oxyhydroxide thin film is formed on the substrate by reactive sputtering (step S4). Here, for example, a nickel oxyhydroxide thin film is formed on the substrate while maintaining the substrate temperature at 10 ° C., the sputtering gas pressure at 50 mTorr, and the RF power at 50 W.

  Thereafter, the substrate on which the nickel oxyhydroxide thin film is laminated is heat-treated at a temperature of 200 to 300 ° C. in the atmosphere (step S5). The heat treatment time is, for example, 1 to 3 hours. When the heat treatment time is less than 1 hour, the durability of the formed nickel oxyhydroxide thin film in the aqueous electrolyte solution becomes insufficient. On the other hand, when the heat treatment time is longer than 3 hours, the width of the transmittance change of the formed nickel oxyhydroxide thin film decreases.

  For the electrochromic thin film formed by the above method, the influence of the heat treatment temperature on the performance of the electrochromic thin film was examined.

(1) A nickel oxyhydroxide thin film produced by a reactive sputtering method using water vapor (H ₂ O) as a reaction gas is heated in air at temperatures of 100 ° C., 200 ° C., 300 ° C., 400 ° C., and 500 ° C. for 2 hours. Absorption spectra of the heat-treated samples were measured by Fourier transform infrared spectroscopy. As shown in FIG. 2, the absorption peak intensity due to the hydrogen-bonded OH group appearing at 2800 to 3700 cm ⁻¹ decreases with an increase in the heat treatment temperature, but a peak is recognized until after the heat treatment at 300 ° C. An absorption peak due to Ni—OH appearing at 560 cm ⁻¹ is also observed after the heat treatment at 300 ° C., but disappears after the heat treatment at 400 ° C.

(2) A nickel oxyhydroxide thin film prepared by a reactive sputtering method using water vapor (H ₂ O) as a reaction gas is heated in air at temperatures of 100 ° C., 200 ° C., 300 ° C., 400 ° C., and 500 ° C. for 2 hours. An X-ray diffraction pattern was measured for the heat-treated sample. As shown in FIG. 3, in the X-ray diffraction pattern of the sample before and after the heat treatment, a broad peak corresponding to the NiOOH (101) plane is observed near the diffraction angle of 42 °. Above 200 ° C., peaks of the NiO (111) plane appear near the diffraction angle of 37 °, and the NiO (200) plane appears around 43 °, and the peak intensity increases as the heat treatment temperature increases.

  The infrared absorption spectrum and X-ray diffraction pattern measurement results are summarized as follows: NiOOH before annealing (as-depo) and heat treatment at 100 ° C., a mixture of NiOOH and NiO at 200 to 300 ° C., and above 400 ° C. It is thought to be NiO.

(3) In order to investigate the cycle dependency of the transmittance change of the electrochromic thin film formed by changing the heat treatment temperature, a nickel oxyhydroxide thin film produced by a reactive sputtering method using water vapor (H ₂ O) as a reactive gas An electrochromic thin film was prepared using a sample heat-treated at 100 ° C., 200 ° C., 300 ° C., 400 ° C., and 500 ° C. for 2 hours in the air. The change in transmittance of the thin film in a weakly acidic electrolyte (H ₂ SO ₄ + KCl aqueous solution, pH = 4) was measured.

  The sample before the heat treatment and after the heat treatment at 100 ° C. rapidly deteriorates when the detachable color cycle is repeated for about 100 cycles, and does not show a color change. Further, in the sample heat treated at 200 ° C., a tendency of deterioration was observed after 250 cycles or more. In contrast, the sample heat-treated at a temperature of 300 ° C. or higher showed almost no deterioration, but the transmittance change of the sample heat-treated at 400 ° C. or higher decreased.

(4) A nickel oxyhydroxide thin film produced by a reactive sputtering method using water vapor (H ₂ O) as a reactive gas was examined in the atmosphere at 100 ° C. and 200 ° C. in order to investigate changes in the optical density change (ΔOD) due to the heat treatment temperature. Electrochromic thin films were prepared using samples heat-treated at 300 ° C., 400 ° C., and 500 ° C. for 2 hours.

  In order to quantitatively represent the magnitude of the transmittance change, the optical density change was determined. Assuming that the transmittance at the time of decolorization is Tb and the transmittance at the time of coloring is Tc, the change in optical density (ΔOD) can be defined by the equation: ΔOD = Log (Tb / Tc).

  FIG. 5 shows ΔOD after 50 cycles and after 300 cycles. As a result, it can be seen that the sample before the heat treatment shows the largest ΔOD after 50 cycles. However, as the detachable color cycle repeats, the deterioration progresses. Therefore, it was found that after 300 cycles, the sample heat-treated at 300 ° C. showed the largest change in optical density, and excellent electrochromic characteristics were obtained.

  Hereinafter, a configuration and a manufacturing method in an embodiment of an electrochromic element having an electrochromic thin film as described above will be described. 6 shows the basic electrochromic device configuration, FIG. 7 shows the main manufacturing process of the basic electrochromic device, FIG. 8 shows the complementary electrochromic device configuration, FIG. 9 shows the main manufacturing steps of a complementary electrochromic device.

  As shown in FIG. 6, the basic electrochromic element 100 includes a first transparent substrate 10, a first transparent electrode 20, a first electrochromic thin film 30, an electrolyte layer 40, and a counter electrode film 50. The second transparent electrode 60 and the second transparent substrate 70 are sequentially stacked.

  The first transparent substrate 10 is a transparent glass substrate or a resin transparent sheet processed into a predetermined dimension.

  The first transparent electrode 20 is formed on the surface of the first transparent substrate 10, and in the case of a liquid crystal display or a solar cell, indium oxide (ITO) added with 5 to 10% tin, Alternatively, a thin film of tin oxide to which fluorine or antimony is added is used. The film thickness is about 100 to 200 nm.

The first electrochromic thin film 30 is a nickel oxyhydroxide thin film formed on the surface of the first transparent electrode 20 by the method shown in FIG. The film thickness is about 100 nm to 1 μm. Tungsten oxide (WO ₃ ), molybdenum oxide (MoO ₃ ), Prussian blue (KxFe ^II yFe ^III z (CN) ₆ ), or the like may be used as the reduction coloring type electrochromic layer. In addition, as an oxidation coloring type electrochromic material, nickel oxide (NiO), nickel hydroxide (Ni (OH) ₂ , NiOOH), cobalt oxide (Co ₃ O ₄ ), cobalt hydroxide (Co (OH) ₂ , CoOOH) In addition, iridium oxide (IrOx) can be used. In addition, many organic materials such as viologen and phthalocyanine can be used, and multi-colors of red, blue and green can be obtained, but the durability (ultraviolet and heat resistance) is superior to inorganic materials. .

The electrolyte layer 40 is an aqueous electrolyte. In this embodiment, an aqueous solution of sulfuric acid or potassium hydroxide (KOH) having a concentration of about 0.1 to 1 mol / L is used. It is also possible to use a lithium-based electrolyte added lithium perchlorate about 0.1 to 1 mol / L in propylene carbonate of an organic material (LiClO _4). Further, a solid electrolyte such as a polymer electrolyte or a proton conductive hydrated oxide may be used. In terms of ion conductivity, the aqueous electrolyte has the highest conductivity and is suitable for high-speed response. The thickness of the electrolyte layer is about 1 μm for a thin-film solid electrolyte, and can be used from several tens of μm to about several mm for a liquid electrolyte.

The counter electrode film 50 is made of cerium oxide (CeO ₂ ). The film thickness is about 100 nm to 1 μm. In this embodiment, the counter electrode film 50 is a 100 nm-thick cerium oxide (CeO ₂ ) film formed by sputtering. Note that platinum (Pt) or ITO may be used as the counter electrode film 50. In many real devices, the electrochromic layer is made of a reduction-colored type and a complementary type using a reduction-colored type material for the counter electrode (see below), or cerium oxide (CeO ₂ ) or the like that does not change color but undergoes a redox reaction. _{Zn-PBA (Zn 3 [Fe} (CN) 6] 2) and the like.

  The second transparent electrode 60 is formed on the surface of the second transparent substrate 70 and has the same configuration as the first transparent electrode 20 described above. The second transparent substrate 70 is the same transparent glass substrate as the first transparent substrate.

A basic manufacturing process of the electrochromic device 100 in the present embodiment will be described. As shown in FIG. 7, when the basic electrochromic device 100 is manufactured, first, the first transparent substrate 10 prepared is an ITO transparent electrode film having a film thickness of 200 nm using a sputtering method. 1 transparent electrode 20 is produced (step S11). Here, a transparent glass substrate was used as the first transparent substrate 10. Next, a NiOOH film having a film thickness of 100 nm is formed on the surface of the formed first transparent electrode 20 as the first electrochromic thin film 30 by using a sputtering method (step S12). Here, the NiOOH film is formed by the procedure shown in FIG. On the other hand, the second transparent electrode 60, which is an ITO transparent electrode film having a thickness of 200 nm, is formed on the surface of the second transparent substrate 70 using a sputtering method (step S13). Here, a transparent glass substrate was used as the second transparent substrate 70. Next, a CeO ₂ counter electrode film 50 having a thickness of 100 nm is formed on the surface of the formed second transparent electrode 60 by using a sputtering method (step S14). Next, for example, the spacer 40a is formed on the outer periphery of the surface of the first transparent substrate 10 on which the first electrochromic thin film 30 is formed (step S15). Next, the first transparent substrate 10 on which the first transparent electrode 20 and the first electrochromic thin film 30 are formed, and the second transparent substrate 70 on which the second transparent electrode 60 and the counter electrode film 50 are formed. Are pasted together with the spacer 40a interposed therebetween (step S16). Next, a mixed aqueous electrolyte (pH = 4) of 5 × 10 ⁻⁵ mol / L sulfuric acid and 1 mol / L KCl is injected into the gap formed by the spacer 40a (step S17). Thereby, a laminated structure of glass substrate / ITO film / NiOOH film / electrolyte layer / CeO ₂ film / ITO film / glass substrate is formed. Finally, the electrolyte inlet is sealed so that the electrolyte does not leak (step S18). Thereby, the electrochromic element 100 is completed.

  As shown in FIG. 8, the complementary electrochromic device 200 includes a first transparent substrate 10, a first transparent electrode 20, a first electrochromic thin film 30, an electrolyte layer 40, and a first electrode as a counter electrode film. 2, the electrochromic thin film 50 </ b> A, the second transparent electrode 60, and the second transparent substrate 70 are sequentially stacked. In this case, since both the first electrochromic thin film 30 and the second electrochromic thin film 50A change in color, the coloring efficiency is improved.

  In the complementary electrochromic element 200 of this embodiment, the first transparent substrate 10, the first transparent electrode 20, the first electrochromic thin film 30, the electrolyte layer 40, the second transparent electrode 60, and the second transparent electrode. The configuration of the material of the substrate 70 is the same as that of the embodiment of FIG.

For the second electrochromic thin film 50A, a material having characteristics opposite to those of the first electrochromic thin film 30 is used. For example, a reduction coloring material WO ₃ was used. The film thickness is the same as that of the first electrochromic thin film 30. Note that a reduction coloring type material (WO ₃ or the like) may be used for the first electrochromic thin film 30, and an oxidation coloring type electrochromic material (NiO or the like) may be used for the second electrochromic thin film 50A.

A manufacturing process of the complementary electrochromic element 200 in this embodiment will be described. As shown in FIG. 9, the complementary electrochromic device 200 is manufactured by first forming a first transparent substrate film having a thickness of 200 nm on the surface of the prepared first transparent substrate 10 using a sputtering method. The electrode 20 is produced (step S21). Here, a transparent glass substrate was used as the first transparent substrate 10. Next, a NiOOH film having a film thickness of 100 nm as the first electrochromic thin film 30 is formed on the surface of the formed first transparent electrode 20 by using a sputtering method (step S22). Here, the NiOOH film is formed by the procedure shown in FIG. On the other hand, the second transparent electrode 60, which is an ITO transparent electrode film having a thickness of 200 nm, is formed on the surface of the second transparent substrate 70 using a sputtering method (step S23). Here, a transparent glass substrate was used as the second transparent substrate 70. Next, a WO ₃ film having a thickness of 100 nm as the second electrochromic thin film 50A is formed on the surface of the formed second transparent electrode 60 by using a sputtering method (step S24). Next, for example, the spacer 40a is formed on the outer periphery of the surface of the first transparent substrate 10 on which the first electrochromic thin film 30 is formed (step S25). Next, the first transparent substrate 10 on which the first transparent electrode 20 and the first electrochromic thin film 30 are formed, the second transparent electrode 60 and the second electrochromic thin film 50A on which the second is formed. The transparent substrate 70 is pasted with the spacer 40a interposed therebetween (step S26). Next, a mixed aqueous electrolyte (pH = 4) of 5 × 10 ⁻⁵ mol / L sulfuric acid and 1 mol / L KCl is injected into the gap formed by the spacer 40a (step S27). Thereby, a laminated structure of glass substrate / ITO film / NiOOH film / electrolyte layer / WO ₃ film / ITO film / glass substrate is formed. Finally, the electrolyte inlet is sealed so that the electrolyte does not leak (step S28). Thereby, the complementary electrochromic element 200 is completed.

As described above, in this embodiment, the electrochromic thin film is formed by forming a nickel oxyhydroxide thin film by reactive sputtering using water vapor (H ₂ O), and the formed nickel oxyhydroxide thin film in the atmosphere. And heat treatment at a temperature of 200 to 300 ° C.

In the method of manufacturing an electrochromic element, first, the first transparent electrode 20 that is an ITO transparent electrode film is formed on the surface of the first transparent substrate 10, and then the surface of the formed first transparent electrode 20 is formed. Then, a NiOOH film having a thickness of 100 nm is produced as the first electrochromic thin film 30, while the second transparent electrode 60 that is an ITO transparent electrode film is formed on the surface of the second transparent substrate 70. Next, a CeO ₂ film having a film thickness of 100 nm (or a WO ₃ film having a film thickness of 100 nm as the second electrochromic thin film 50A) is formed as the counter electrode film 50 on the surface of the formed second transparent electrode 60, and then Then, the spacer 40a is formed, and then the first transparent substrate 10 and the second transparent substrate 70 are bonded to each other with the spacer 40a interposed therebetween, and then 5 × 10 ⁻⁵ mol / in the gap formed by the spacer 40a. A mixed aqueous electrolyte of L sulfuric acid and 1 mol / L KCl is injected, and finally the electrolyte inlet is sealed so that the electrolyte does not leak.

  Thereby, the nickel oxyhydroxide thin film which can use the aqueous solution electrolyte (pH = 4) near neutrality, and an electrochromic element provided with the same can be produced. Moreover, the nickel oxyhydroxide thin film which can be used in acidic aqueous solution electrolyte, and an electrochromic element provided with the same can be produced.

  All the embodiments described above are illustrative of the present invention and are not intended to be limiting, and the present invention can be implemented in other various modifications and changes. Therefore, the scope of the present invention is defined only by the claims and their equivalents.

  The method for forming an electrochromic thin film of the present invention can use an aqueous electrolyte close to neutrality or an acidic aqueous electrolyte, and has higher ionic conductivity than those using an organic electrolyte or a solid electrolyte conventionally used. It can be used for the purpose of producing a fast response electrochromic device. The electrochromic element can be used for light control glass, an antiglare mirror for automobiles, and electronic paper.

DESCRIPTION OF SYMBOLS 10 1st transparent substrate 20 1st transparent electrode 30 1st electrochromic thin film 40 Electrolyte layer 40a Spacer 50 Counter electrode film 50A 2nd electrochromic thin film 60 2nd transparent electrode 70 2nd transparent substrate 100 Basic Electrochromic element 200 Complementary electrochromic element

Claims (7)

  A method for forming an electrochromic thin film, comprising forming a nickel oxyhydroxide thin film by reactive sputtering using water vapor, and heat-treating the formed nickel oxyhydroxide thin film at a temperature of 200 to 300 ° C. in the atmosphere. .   The method for forming an electrochromic thin film according to claim 1, wherein the heat treatment time is 1 to 3 hours. A first transparent electrode forming step of forming a first transparent electrode on the surface of the first transparent substrate;
A first electrochromic thin film forming step of forming a first electrochromic thin film on the surface of the formed first transparent electrode;
A second transparent electrode forming step of forming a second transparent electrode on the surface of the second transparent substrate;
A counter electrode film forming step of forming a counter electrode film on the surface of the formed second transparent electrode;
An electrolyte layer is interposed between the first transparent substrate on which the first transparent electrode and the first electrochromic layer are formed, and the second transparent substrate on which the second transparent electrode and a counter electrode film are formed. An assembly process for stacking,
In the first electrochromic thin film forming step, a nickel oxyhydroxide thin film is formed by reactive sputtering using water vapor, and the formed nickel oxyhydroxide thin film is heat-treated at a temperature of 200 to 300 ° C. in the atmosphere. A method for producing an electrochromic device. A spacer forming step of forming a spacer on the outer periphery of the surface of the first electrochromic layer formed on the first transparent substrate, or on the outer periphery of the surface of the counter electrode film formed on the second transparent substrate;
The first transparent substrate on which the first transparent electrode and the first electrochromic layer are formed, and the second transparent substrate on which the second transparent electrode and a counter electrode film are formed are sandwiched by the spacer. The method for manufacturing an electrochromic device according to claim 3, further comprising an electrolyte injection step of injecting an electrolyte into the space formed by the spacer in a state of being bonded together. 5. The method of manufacturing an electrochromic device according to claim 3, wherein in the counter electrode film forming step, a CeO ₂ film having a film thickness of 100 nm to 1 μm is formed by a sputtering method. 5. The method of manufacturing an electrochromic device according to claim 3, wherein in the counter electrode film forming step, a WO ₃ film having a film thickness of 100 nm to 1 μm is formed by a sputtering method. The electrochromic device manufacturing method according to any one of claims 4 to 6, wherein in the electrolyte injection step, a mixed aqueous electrolyte of 5 × 10 ^-5 mol / L sulfuric acid and 1 mol / L KCl is used. Method.

Images