KR102042797B1 - Electrochromic device with hybrid electrolyte and method of fabricating the same - Google Patents

Abstract

The present invention relates to an electrochromic device including a composite electrolyte layer capable of preventing the structural weakening of the electrochromic device, and improving the electrical stability and durability of the electrochromic device by efficiently supplying electrons to a positive electrode film in which the electrons are supplied to the outside in an initial operation; and to a manufacturing method of the electrochromic device. In the electrochromic device, a first electrode, a negative electrode film, an electrolyte layer, a positive electrode film, and a second electrode are sequentially stacked between first and second transparent substrates facing each other at a predetermined interval. The electrolyte layer comprises: a first electrolyte layer providing electrolyte ions only with the negative electrode film and the positive electrode film; and a second electrolyte layer formed to have a thickness thinner than that of the first electrolyte layer by mixing a reducing agent in the same electrolyte as the first electrolyte layer, and formed between the first electrolyte layer and the positive electrode film.

Description

Electrochromic device comprising a composite electrolyte layer and a method for manufacturing the same {Electrochromic device with hybrid electrolyte and method of fabricating the same}

The present invention relates to an electrochromic device and a method of manufacturing the same, and more particularly, a first electrolyte layer for providing electrolyte ions to a cathode membrane and an anode membrane, and a second electrolyte layer added with a reducing agent to the electrolyte. The present invention relates to an electrochromic device and a method of manufacturing the same, which can improve electrical stability and durability by preventing structural weakening of the device by efficiently supplying electrons to the anode film which is donated to the outside during initial driving.

Electrochromism is a phenomenon in which a color is reversibly changed in the electric field direction when a voltage is applied. An element having such characteristics is called an electrochromic device. Electrochromic devices are not colored when there is no electron transfer from the outside, but become colored when the electrons are supplied and reduced or oxidized due to the loss of electrons. The color disappears when it is supplied and reduced or oxidized due to the loss of electrons.

Electrochromic devices are used to adjust the light transmittance or reflectivity of building window glass or automobile mirrors. Recently, it is known that not only the color change in the visible light range but also the infrared blocking effect is applied to the application of energy-saving products. It is also receiving great attention.

The structure of the electrochromic device is shown in FIG. 1. Referring to FIG. ), The electrolyte layer 14, the anode film 15, and the second electrode 16 are sequentially stacked. In general, an inorganic material such as nickel oxide (NiOx) that is oxidized and discolored by the cathode film 13 is reduced and discolored by the anode film 15 such as tungsten oxide (WOx). When an external power source is applied to the first electrode 12 and the second electrode 16, electrolyte ions such as H ⁺ , Li ⁺ , Na ⁺ are transferred to the anode film 15 and the cathode film 13, and at the same time, The electrons move to color or decolorize.

 FIG. 2 is a diagram illustrating the movement of electrons and electrolyte ions during the initial driving of the electrochromic device. Referring to FIG. 2, electrons are supplied from the anode film 15 to the cathode film 13 when power is applied to the device. In the initial driving of the device, electrons are supplied in a state in which electrolyte ions are present only in the electrolyte layer 14 and not in the anode film 15. Therefore, due to the rapid outflow of electrons from the anode film 15 during the initial driving of the color change device, the structure of the anode film becomes weak and there is a problem that the characteristics of the entire device are degraded.

Patent Document 1: Republic of Korea Patent Publication No. 2006-0092362 (August 23, 2006)

The present invention was devised to solve the above problems, and an object of the present invention is to prevent the structural weakening of the device by efficiently supplying electrons to the anode film in the initial state of the device that does not have electrolyte ions in the anode film. The present invention provides an electrochromic device and a method of manufacturing the same that can improve stability and durability.

In order to achieve the above object, the present invention provides an electrochromic device in which a first electrode, a cathode film, an electrolyte layer, an anode film, and a second electrode are sequentially stacked between opposing first and second transparent substrates at predetermined intervals. The electrolyte layer may include a first electrolyte layer that provides electrolyte ions only with the cathode membrane and the anode, and a reducing agent is mixed with the same electrolyte as the first electrolyte layer between the first electrolyte layer and the anode membrane. An electrochromic device including a second electrolyte layer formed to a thinner thickness is provided.

In the present invention, the reducing agent is preferably any one of ferrocene (ferrocene), ferrocene derivatives, hydroquinone (hydroquinone), hydroquinone derivatives.

In the present invention, the reducing agent is preferably included in 0.03mM to 0.08mM with respect to the total content of the electrolyte forming the second electrolyte layer.

In the present invention, the second electrolyte layer is preferably formed to a thickness of 0.1% to 20% of the thickness of the electrolyte layer.

In the present invention, the electrolyte is preferably a liquid electrolyte containing an ultraviolet curable resin.

In addition, the present invention is a step of sequentially stacking a first electrode, a cathode film, a first electrolyte layer on a first transparent substrate, a step of sequentially stacking a second electrode, an anode film on a second transparent substrate, the first After the reducing agent is mixed with the same electrolyte as the electrolyte layer, the reducing agent is coated on the anode layer to form a liquid second electrolyte layer, and the first transparent substrate is formed on the liquid second electrolyte layer in which the second transparent substrate is laminated. It provides a method of manufacturing an electrochromic device comprising bonding the interface of the stacked first electrolyte layer.

In the present invention, the reducing agent is preferably mixed at 0.03mM to 0.08mM with respect to the total content of the electrolyte forming the second electrolyte layer.

In the present invention, the second electrolyte layer is preferably applied in a thickness of 0.1% to 20% of the thickness of the electrolyte layer.

In the present invention, after the interface bonding of the liquid second electrolyte layer and the first electrolyte layer, it is preferable to further include the step of ultraviolet curing the second electrolyte layer bonded to the interface.

According to the present invention, since the second electrolyte layer made of the same electrolyte as the first electrolyte layer providing the electrolyte ions is closely bonded to each other, the interface resistance is low, so that the electrolyte ions can be moved smoothly. Through the reducing agent added to the electrolyte layer, the electrons are efficiently supplied to the anode film, which provides electrons to the outside during initial operation of the device, thereby preventing structural weakness of the device, thereby improving electrical stability and durability.

1 is a view showing the structure of a conventional electrochromic device.
2 is a diagram illustrating the movement of electrons and electrolyte ions during the initial driving of the electrochromic device.
3 is a block diagram showing an electrochromic device according to the present invention.
4 is a diagram illustrating an interfacial bonding process between a first electrolyte layer and a second electrolyte layer according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the present invention illustrated below may be modified in many different forms, and the scope of the present invention is not limited to the embodiments described below.

3 is a view illustrating a configuration of an electrochromic device according to the present invention. Referring to FIG. 3, the electrochromic device according to the present invention may include a first interposed between first and second transparent substrates 110 and 170 facing each other at a predetermined interval. The electrode 120, the cathode film 130, the electrolyte layer 140, the anode film 150, and the second electrode 160 are sequentially stacked.

As the first and second transparent substrates 110 and 170, a glass substrate or a transparent polymer substrate may be used.

The first electrode 120 and the second electrode 130 are transparent electrodes formed on opposite surfaces of the first transparent organ 110 and the second transparent substrate 170, respectively, and are indium doped tin oxide (ITO) and ATO. (Antimony doped Tin Oxide), Fluorine doped Tin Oxide (FTO), Indium doped Zinc Oxide (IZO), ZnO, etc.

The first electrode 120 and the second electrode 130 may be formed in a thin film form on the transparent organ (110, 170) through a sputtering process, within the range of 1nm to 1㎛, 150nm or more, 200nm or more, or 300nm or more It may have a thickness.

The negative electrode layer 130 and the positive electrode layer 150 are formed on the first electrode 120 and the second electrode 130, respectively, and are discolored due to the movement of electrolyte ions. The negative electrode layer 130 is oxidized and discolored. Layer, and the anode film 150 is a layer which is reduced and discolored. The cathode layer 130 and the anode layer 150 include an electrochromic material that changes color according to an electrical signal, and may be an organic or inorganic electrochromic material. The organic electrochromic material may be made of viologen, anthraquinone, polyaniline, polypinol or polythiophene, and may include Ti, Nb, Mo, Ta, W, V, Cr, Mn, Fe, Co, Ni, Rh, And one or more oxides of the oxides of Ir as the inorganic discoloration material.

When the discoloration material of the cathode film 130 and the anode film 150 is decolored, the electrochromic device transmits incident light, and when colored, the transmittance of the incident light decreases, thereby changing the optical properties of the electrochromic device. Coloring and decolorization reactions may occur alternately depending on the polarity of the applied voltage, or the direction of current flow. The cathode film 130 and the anode film 150 have a transmittance of 20% to 50% of visible light at the time of coloring, and a transmittance of 50% to 75% of visible light at the time of decolorization.

The electrolyte layer 140 is a layer that provides a migration environment of hydrogen ions or lithium ions for discoloration or discoloration of the electrochromic material. In the present invention, the electrolyte layer 140 provides electrolyte ions to the cathode membrane 130 and the anode membrane 150. It comprises a first electrolyte layer 141 and a second electrolyte layer 142 formed of a thickness thinner than the first electrolyte layer 141 by mixing a reducing agent in the same electrolyte as the first electrolyte layer 141. As such, since the first electrolyte layer 141 and the second electrolyte layer 142 are made of the same electrolyte, the interfacial resistance is small at the time of bonding, so that the electrolyte ions can be smoothly moved, so that the discoloration efficiency of the device is not reduced. An interface bonding method of the first electrolyte layer 141 and the second electrolyte layer 142 will be described later.

The electrolyte used in the first electrolyte layer 141 and the second electrolyte layer 142 may be a liquid polymer electrolyte containing ultraviolet curable resin and curable according to ultraviolet irradiation. The ultraviolet curable resin may be formed by mixing a PEG-based oligomer, a low molecular weight PEGDMe, a photoinitiator, and an electrolyte salt is mixed therein to form an electrolyte. As the electrolyte salt, a compound containing H ⁺ , Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ may be used. For example, a lithium salt compound such as LiClO ₄ , LiBF ₄ , LiAsF ₆ , or LiPF ₆ may be used. Can be.

According to the present invention, the second electrolyte layer 142 is formed by mixing a reducing agent in the above-described electrolyte, and as a reducing agent, ferrocene (ferrocene), methyl ferrocene (Methylferrocene), dimethyl ferrocene (Dimethylferrocene), acetyl ferrocene (Acethylferrocene), ethyl Ferrocene (Ethylferrocene), Vinyl ferrocene (Vinylferrocene), Diphenylferrocene (Diphenylferrocene), Methoxy-methylferrocene, Butyl ferrocene (t-butylferrocene), Chloromethyl ferrocene (Chloro) ferrocene derivatives such as methyl ferrocene, Hydroquinone, Methylhydroquinone, Methoxyhydroquinone, Acetylhydroquinone, Dimethylhydroquinone, Trimethylhydroquinone Ethylhydroquinone, Butylhydroqunone, t-butylhydroquinone and t-butylhydroquinone It can be used any one of the hydroquinone derivative.

As shown in FIG. 3, as the reducing agent is mixed with the second electrolyte layer 142 and formed on the anode film 150, the cathode film 150 is formed from the reducing agent of the second electrolyte layer 142 during initial driving of the device. Electrons can be supplied. In order to smoothly supply and transport electrons, the reducing agent may be mixed to include 0.03 mM to 0.08 mM with respect to the total content of the electrolyte forming the second electrolyte layer 142. In addition, the second electrolyte layer 142 is formed to a thickness thinner than the first electrolyte layer 141, preferably 0.1% to 20% of the thickness of the entire electrolyte layer 140. If the thickness of the second electrolyte layer 142 exceeds 20%, there is a problem that the decolorization degree is lowered due to the color of the reducing agent to be mixed. If the thickness is less than 0.1%, the amount of the reducing agent added is small so that electrons cannot be supplied smoothly. .

Hereinafter, a method of manufacturing the electrochromic device according to the present invention will be described. In the electrochromic device according to the present invention, the first electrode 120, the cathode film 130, and the first electrolyte layer 141 are sequentially stacked on the first transparent substrate 110 (S110) and the second transparent substrate. After sequentially stacking the second electrode 160 and the anode film 150 on the substrate 170 (S120), the reducing agent is mixed with the same electrolyte as the first electrolyte layer 141, and then the anode film 150. Forming a liquid second electrolyte layer 142 by coating on the step (S130), the first transparent substrate 110 is laminated on the liquid second electrolyte layer 142 on which the second transparent substrate 170 is laminated. It is manufactured including the step (S140) of bonding the interface of the first electrolyte layer 141.

The method of forming the electrodes 120 and 160, the thin films 130 and 150, and the electrolyte layers 141 and 142 is not particularly limited, and a known method may be used. For example, any one of deposition, spin coating, dip coating, screen printing, gravure coating, sol-gel, or slot die coating can be used. Each layer can be provided by.

As described above, the second electrolyte layer 142 manufactured by mixing the electrolyte and the reducing agent is coated on the anode film 150 with a thickness of 0.1% to 20% of the total thickness of the electrolyte layer 140 and is bonded to the first electrolyte. Bonded in a liquid state for close contact with layer 141. That is, the thicker first electrolyte layer 141 is ultraviolet-cured and solidified, and then interfacially bonded with the liquid second electrolyte layer 142, and the second electrolyte layer 142 is interfacially bonded to the electrolyte layer. 140 is formed. An interface bonding process between the first electrolyte layer 141 and the second electrolyte layer 142 is illustrated in FIG. 4. Since the first electrolyte layer 141 and the second electrolyte layer 142 made of the same electrolyte are closely bonded to each other, the electrolyte layer 140 formed as described above has a low interfacial resistance, which enables smooth electrolyte ion migration, thereby improving discoloration efficiency of the device. In addition, electrons may be smoothly supplied from the reducing agent of the second electrolyte layer 142 to the anode film 150 during the initial driving of the device.

<Example>

After forming an ITO electrode on the glass substrate and forming a nickel oxide layer (NiOx) on the negative electrode film 130 thereon, after applying the ultraviolet curing electrolyte to the nickel oxide layer 0.05mm thickness using the first electrolyte layer 141 Cured. After forming an ITO electrode on a glass substrate and forming a tungsten oxide layer (WOx) on the anode film 150 thereon, 0.5mM Acetyl Ferrocene is mixed with the same electrolyte as the first electrolyte layer 141 and then oxidized. An electrochromic device was fabricated by applying a thickness of 0.005 mm to the tungsten layer and interfacially bonding the first electrolyte layer 141 in a liquid state to UV curing. A voltage of -1.5V to + 1.5V was applied to the fabricated device, and the nickel oxide layer and tungsten oxide layer were stably discolored according to the polarity of the applied power, and the light transmittance was measured at 20%. This was measured at 65% and confirmed excellent light transmittance upon decolorization even if a reducing agent was added to the electrolyte.

11, 110: first transparent substrate 12, 120: first electrode
13, 130: cathode membrane 14, 140: electrolyte layer
141: first electrolyte layer 142: second electrolyte layer
15, 150: anode film 16, 160: second electrode
17, 170: second transparent substrate

Claims (9)

In an electrochromic device in which a first electrode, a cathode film, an electrolyte layer, an anode film, and a second electrode are sequentially stacked between opposing first and second transparent substrates at predetermined intervals,
The electrolyte layer,
A first electrolyte layer providing electrolyte ions only by the cathode membrane and the anode; And,
And a second electrolyte layer formed by mixing a reducing agent in the same electrolyte as the first electrolyte layer between the first electrolyte layer and the anode film.
The reducing agent of the second electrolyte is mixed with 0.03mM to 0.08mM with respect to the total content of the second electrolyte layer electrolyte, the electrochromic device, characterized in that formed in 0.1% ~ 20% thickness of the entire electrolyte layer. The method of claim 1,
The reducing agent is an electrochromic device, characterized in that any one of ferrocene (ferrocene), ferrocene derivatives, hydroquinone (hydroquinone), hydroquinone derivatives. delete delete The method of claim 1,
The electrolyte is an electrochromic device, characterized in that the liquid electrolyte containing the ultraviolet curable resin. In the method of manufacturing the electrochromic device,
Sequentially stacking a first electrode, a cathode film, and a first electrolyte layer on the first transparent substrate;
Sequentially stacking a second electrode and an anode film on the second transparent substrate;
Mixing a reducing agent in the same electrolyte as the first electrolyte layer, and then coating the cathode to form a liquid second electrolyte layer; And
Bonding the interface of the first electrolyte layer on which the first transparent substrate is laminated to the liquid second electrolyte layer on which the second transparent substrate is laminated;
The second electrolyte layer is 0.03mM to 0.08mM with respect to the total content of the electrolyte is mixed with the reducing agent, the manufacturing method of the electrochromic device, characterized in that to form a thickness of 0.1% to 20% of the entire electrolyte layer. delete delete The method of claim 6,
After the interface bonding of the liquid second electrolyte layer and the first electrolyte layer,
The method of manufacturing an electrochromic device, characterized in that it further comprises the step of ultraviolet curing the second electrolyte layer bonded to the interface.

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