KR20230034034A - Method for manufacturing an organic-inorganic hybrid binder for a photoelectrochromic layer of a photoelectrochromic device, organic-inorganic hybrid binder produced by this, and a photoelectrochromic device comprising the same - Google Patents

Abstract

The present invention relates to a method for manufacturing an organic-inorganic hybrid binder for a photoelectrochromic layer of a photoelectrochromic element, an organic-inorganic hybrid binder produced thereby, and a photoelectrochromic device including the same. The method for manufacturing the organic-inorganic hybrid binder for a photoelectrochromic layer of the photoelectrochromic element comprises the steps of: reacting a trivalent alkoxy silane having a photo-curable or thermally curable functional group and at least one monovalent to tetravalent organic silane having a polar group at room temperature in the presence of an acid or base catalyst, and performing a reflux reaction at 70 to 80℃; and replacing alcohol produced through the reaction with a solvent different from the alcohol and then mixing an initiator to manufacture an organic-inorganic hybrid binder having a siloxane structure. In addition, the organic-inorganic hybrid binder is mixed with a photoelectrochromic material to be applied on an electrode, and then photo-cured in a 300 to 400 nm UV range or thermally cured at 100 to 150℃. Accordingly, electrochemical durability of the photoelectrochromic element can be secured.

Description

Method for manufacturing an organic-inorganic hybrid binder for a photoelectric chromic layer of a photoelectrochromic device, an organic-inorganic hybrid binder produced thereby, and a photoelectrochromic device including the same -INORGANIC HYBRID BINDER PRODUCED BY THIS, AND A PHOTOELECTROCHROMIC DEVICE COMPRISING THE SAME}

The present invention relates to a method for manufacturing an organic-inorganic hybrid binder for a photoelectrochromic layer of a photoelectrochromic device, an organic-inorganic hybrid binder prepared thereby, and a photoelectrochromic device including the same.

Electrochromism is a phenomenon in which the color changes reversibly in the direction of an electric field when a voltage is applied. do. The electrochromic material is colorless when an external electrical signal is not applied, but becomes colored when an electrical signal is applied, or conversely, it is colored when no external signal is applied, and then becomes colored when a signal is applied. It has this extinction characteristic.

An electrochromic element is an element in which a discoloration effect occurs by a reaction of an electrochromic material, and includes a pair of electrodes, an electrolyte layer disposed between the pair of electrodes, and an electrolyte layer disposed between any one of the pair of electrodes and the electrolyte layer. It has an electrochemical structure including an ion storage layer disposed on the ion storage layer and an electrochromic layer disposed between the electrolyte layer and the other electrode of the pair of electrodes.

However, electrochromic devices have the disadvantage that electricity must be applied from the outside for coloring and discoloration, so photoelectrochromic devices that combine solar cells and electrochromic devices that can obtain necessary electricity from sunlight are attracting attention as energy-saving electrochromic devices. have received

In the photoelectrochromic element, when light is irradiated, a potential difference is generated by photoelectrons, and ions or electrons included in the electrolyte layer move into the photoelectrochromic layer and undergo an oxidation-reduction reaction, resulting in a visible color change due to a change in absorption wavelength or absorption rate. It is composed of the principle that changes or the shading of color changes.

As such, the photoelectrochromic element not only secures visibility but also allows users to actively adjust the transmittance, enabling various color changes and having a wide range of applications such as smart windows, car room mirrors, laptops, mobile phones and decorative designs. Various technologies related to photoelectrochromic devices are being studied.

As the electrochromic material used in the photoelectrochromic element, inorganic materials such as cobalt, indium, iridium, and tungsten may be used, and viologen, prussian blue, and perylene dimide may be used. Organic materials such as series can be used.

Among them, viologen has the advantages of simple synthesis, color change at low voltage, and high ion conductivity, but it takes a long color conversion time, low color efficiency, and weak mechanical properties.

In order to improve the color transmittance efficiency of the electrochromic material, a deposition material, an inorganic material-based coating material, or a coating material through a high-temperature heat treatment process have been developed for the photoelectrochromic layer, but thick film formation is difficult due to high process cost and brittleness of the material itself. It is impossible, and the coloring efficiency is rather reduced, so there is a limit to the application to the photoelectrochromic device.

In 'Method for Manufacturing Electrochromic Layer by Wet Coating Method and Electrochromic Device Containing It (Public No.: 10-2016-0127866)', nickel oxide particles or nickel oxide particles doped with cations and a hydrolyzed inorganic binder are included. A method of wet coating the coating solution on the electrode is proposed. However, there are problems in that the process cost is high, the formation of a thick film is difficult due to the brittleness of the coating solution itself, and the coloring efficiency is also reduced.

Therefore, there is an urgent need to develop a new binder that can be applied to a photoelectric chromic layer of a photoelectric chromic device by increasing light resistance and chemical resistance while increasing the coloring efficiency of the electrochromic material.

Domestic Patent Publication No. 10-2016-0127866, published on November 7, 2016.

The present invention was invented to solve the above problems, and a method for manufacturing an organic-inorganic hybrid binder for a photoelectric chromic layer of a photoelectric chromic element, which can stably disperse and mix a photoelectric chromic material to increase color fading efficiency, and manufactured thereby It is a technical challenge to provide an organic-inorganic hybrid binder and a photoelectrochromic device including the same.

In order to solve the above technical problem, the present invention, in the presence of an acid or base catalyst, a trivalent alkoxy silane having a photocurable or thermally curable functional group and at least one organic silane having a monovalent to tetravalent polar group are reacted at room temperature After the reflux reaction at 70 to 80 ℃; and replacing the alcohol generated through the reaction with a solvent different in kind from the alcohol and then mixing an initiator to prepare an organic-inorganic hybrid binder having a siloxane structure, wherein the organic-inorganic hybrid binder comprises a photoelectric Provides a method for manufacturing an organic-inorganic hybrid binder for a photoelectric color layer of a photoelectric color change device, characterized in that it is mixed with a color change material and applied on an electrode and then photocured in a 300 to 400 nm UV region or thermally cured at 100 to 150 ° C. do.

Preferably, dispersing at least one of organic particles and inorganic particles in the organic-inorganic hybrid binder.

Preferably, the photoelectrochromic material includes an oxidative discoloration material or a reductive discoloration material, wherein the oxidative discoloration material includes vanadium (V) oxide, chromium (Cr) oxide, manganese (Mn) oxide, iron (Fe) oxide, At least one of cobalt (Co) oxide, nickel (Ni) oxide, rhodium (Rh) oxide, and iridium (Ir) oxide, and the reduction discoloration material is titanium (Ti) oxide, copper (Cu) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, niobium (Nb) oxide, and tantalum (Ta) oxide.

In order to solve the above other technical problems, the present invention reacts a trivalent alkoxysilane having a photocurable or thermally curable functional group and at least one organic silane of monovalent to tetravalent having a polar group at room temperature in the presence of an acid or base catalyst. And an organic-inorganic hybrid binder having a siloxane structure is formed by replacing the alcohol generated through the reflux reaction at 70 to 80 ° C with a solvent different from the alcohol, and then mixing the initiator, wherein the organic-inorganic hybrid binder , Organic-inorganic hybrid for photoelectrochromic layer of photoelectrochromic element, characterized in that it is mixed with a photoelectrochromic material and applied on an electrode and then photocured in a 300 to 400nm UV region or thermally cured at 100 to 150 ° C to form a coating film. Binders are provided.

In order to solve the above another technical problem, the present invention, a first electrode; a second electrode facing the first electrode; an electrolyte layer disposed between the first electrode and the second electrode; a first photoelectric color change layer disposed between the first electrode and the electrolyte layer; and a second photoelectric chromic layer disposed between the second electrode and the electrolyte layer, wherein the first photoelectric chromic layer and the second photoelectric chromic layer are photocurable or thermally curable functional groups in the presence of an acid or base catalyst. A trivalent alkoxy silane having a polar group and at least one organic silane having a polar group of 1 to 4 are reacted at room temperature and an alcohol produced through a reflux reaction at 70 to 80 ° C. is replaced with a solvent different from the alcohol. an organic-inorganic hybrid binder having a siloxane structure formed by mixing a post-initiator; And photoelectrochromic material; is formed by mixing, photocuring in the 300 to 400nm UV region, or thermally cured at 100 to 150 ℃, it provides a photoelectrochromic element.

The organic-inorganic hybrid binder of the present invention by means of solving the above problems can be formed as a coating film of various thicknesses on the electrode, from a thin film having a thickness of 5 μm or less to a thick film of more than 5 μm through a low-temperature wet process. There is an effect that can be applied as a binder required in the photoelectrochromic layer of the photoelectrochromic device because the efficiency of color transmittance is improved through the.

In addition, since the organic-inorganic hybrid binder has improved moisture resistance and surface hardness and can be formed in a single-layer structure without the need to form a multi-layered photoelectrochromic layer, it can not only serve as a coating film but also inner layer required as the outermost coating layer. It has the effect of acting as a wet and high hardness binder.

In addition, since it is possible to impart flexibility to the coating film made of the photoelectric chromic layer by grafting an organic-inorganic hybrid binder to the photoelectrochromic material, it can respond to changes in curvature and can be applied to various curved substrates, and pinholes are formed on the surface of the photoelectrochromic layer. There is no such defect, so there is an effect of improving the long-term stability and color reproducibility of the photoelectrochromic device.

In addition, the photoelectrochromic layer including the organic-inorganic hybrid binder has sufficient chemical resistance not to dissolve in electrolyte components when in contact with the electrolyte layer, thereby ensuring the electrochemical durability of the photoelectrochromic device.

1 is a configuration diagram showing a photoelectrochromic device according to the present invention.

Hereinafter, the present invention will be described in detail.

In one aspect, the present invention relates to an organic-inorganic hybrid binder for a photoelectrochromic layer of a photoelectric color change device, and a method for manufacturing the same.

A method for preparing an organic-inorganic hybrid binder for forming a photoelectrochromic layer of a photoelectrochromic device is one of a trivalent alkoxy silane having a photocurable or thermally curable functional group and a monovalent to tetravalent alkoxysilane having a polar group in the presence of an acid or base catalyst. After reacting the organic silane at room temperature and then performing a reflux reaction at 70 to 80 ° C. (S10), the alcohol produced through the reaction is replaced with a solvent different from the alcohol, and then an initiator is mixed to form a siloxane. It is characterized in that it comprises a step of preparing an organic-inorganic hybrid binder having a structure (S20), and a step of dispersing at least one of organic particles and inorganic particles in the organic-inorganic hybrid binder (S30).

According to the above-described preparation method, first, a trivalent alkoxy silane having a photocurable or thermally curable functional group and at least one organic silane having a polar group of 1 to 4 are reacted at room temperature in the presence of an acid or base catalyst, followed by a reaction at room temperature of 70 to 80 °C. The reflux reaction is performed at ° C (S10).

A chemical bond may be induced by additionally adding silane capable of exhibiting adhesion to a substrate among monovalent to tetravalent alkoxysilanes to the trivalent alkoxy silane having a photocurable or thermocurable functional group. This is to ensure long-term durability of the photoelectrochromic layer by inducing chemical bonding with various substrates by introducing functional groups such as hydroxyl groups, amine groups, mercapto groups, and epoxy groups of silane to the surface of siloxane. It is for

According to this chemical bond, dispersion of a photoelectrochromic material, such as a metal oxide, can be facilitated through an organic silane having a trivalent heat or photocurable functional group and an organic silane having a polar group among 1, 2, 3, and 4 valent silanes. there will be In addition, when an organic material is used as the photoelectrochromic material, an organic silane having a hydrophobic group may be used according to polarity to be synthesized with photocurable or thermosetting silane. Accordingly, by controlling the surface properties of the organic-inorganic hybrid binder having a siloxane structure with a combination of organic alkoxysilanes having a hydrophilic or hydrophobic organic group, it is possible to facilitate dispersion in various polar and non-polar solvents, and photoelectric discoloration having various surface properties. An organic-inorganic hybrid binder for forming a photoelectrochromic layer may be prepared by stably dispersing the material.

As a specific process for preparing a photocurable or thermocurable organic-inorganic hybrid siloxane binder, monovalent, divalent, trivalent, and tetravalent siloxane binders are prepared as necessary based on organic silanes having a photocurable or thermocurable functional group in trivalent alkoxy. One or more of the organic alkoxy silanes may be mixed, and the reaction may be carried out at room temperature and 70 to 80 ° C. as a reflux solution using a catalyst.

In synthesizing the organic-inorganic hybrid binder having a siloxane structure, an acid catalyst or a base catalyst may be used as a catalyst. The acid catalyst may be at least one selected from the group consisting of nitric acid, hydrochloric acid, formic acid, acetic acid, and phosphoric acid, and the base catalyst may be at least one selected from the group consisting of metal hydroxide and ammonium hydroxide. The oxide may be one or more of sodium hydroxide, barium hydroxide, calcium hydroxide and potassium hydroxide.

Monovalent, divalent, trivalent and tetravalent means the number of alkoxy groups in the molecule of the organic alkoxy silane. For example, trivalent organic alkoxy silane means a silane composed of 3 alkoxy groups and 1 organic group in tetravalent silicon. One organic group may include a reactive group or an alkyl group that can be crosslinked by light or heat, which means that the configuration or structural design can be changed according to the process or the physical properties required in the photoelectrochromic device and the application purpose.

A trivalent alkoxy silane having a photocurable or thermocurable functional group and at least one organic silane having a polar group of 1 to 4 may be mixed in a molar ratio of 50 to 99.9 : 0.1 to 50. If the molar ratio of trivalent alkoxy silane is less than 50, photocuring or thermal curing may take a lot of time, resulting in inefficiency. there is. If the amount of one or more of the monovalent to tetravalent organic silanes having a polar group is less than 0.1 molar ratio, it is difficult to secure flexibility due to an insufficient amount to make the siloxane of the binder have a linear structure, and if it exceeds 50 molar ratio, it is rather difficult to control the molecular weight.

If the amount of divalent silane among the silanes that can be additionally added according to the required physical properties of the organic-inorganic hybrid binder is increased, the siloxane structure of the binder has a linear structure, thereby securing flexibility, which can prevent external impact and curvature when forming a thick film. This means that it is possible to increase the mitigation effect and durability against internal mechanical stress that may be caused by the coating of the back.

When monovalent silane is added, the molecular weight of the binder and the surface properties of the siloxane can be more clearly controlled. When the amount of tetravalent silane is increased, the hardness and molecular weight of the coating film can be increased, so the amount of additionally added silane can be freely controlled. In particular, it is preferable to proceed by additionally introducing divalent silane among 1, 2, 3, and 4 valent silanes in order to wet process to form a thick film.

Trivalent alkoxysilanes include trimethoxysilane, triethoxysilane, tri-n-propoxysilane, triisopropoxysilane, and methyltrimethoxysilane. (methyltrimethoxysilane), methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-epoxycyclohexylethyltrimethoxysilane and 3-glycol It may be any one or more of sidoxypropyltrimethoxysilane (3-glycidoxypropyltrimethoxysilane).

Silane used in this step may include 60 to 100% by weight of the total solids contained in the organic-inorganic hybrid binder. If the amount of silane is less than 60% by weight based on the total solid content of the organic-inorganic hybrid binder, there is a disadvantage in that it cannot be easily dispersed in various polar or non-polar solvents.

Next, an organic-inorganic hybrid binder having a siloxane structure is prepared by replacing the alcohol generated through the reaction with a solvent different from the alcohol and then mixing an initiator (S20).

The solvent is for controlling the viscosity and solid content according to the thickness of the finally formed coating film, and the solid content is adjusted to 10 to 60% by weight of the total weight of the organic-inorganic hybrid binder. As the replacement solvent, one or more of water, cellosolves, acetates, and ketones may be used.

Regarding the initiator, a photocuring initiator may be used for photocuring, and a thermal curing initiator may be used for thermal curing. A photocuring initiator may be benzyl dimethyl ketone (BDK), and a thermal curing initiator may be B5428 (TCI).

The initiator may be added in the range of 1 to 3% of the total weight of the silane added to the synthesis. If it is added in less than 1%, a lot of time is consumed for photocuring or thermal curing, resulting in reduced productivity, and if it is added in excess of 3% If it is, it may help to accelerate the curing speed, but it may cause modification of the physical properties of the coating film, which is not preferable.

Organic-inorganic hybrid binders can be dispersed in polar, neutral or non-polar solvents to control surface and polarity, dispersing not only polar solvents including water and alcohol, but also neutral solvents such as Cellosolve and non-polar solvents such as ketones. this could be possible Accordingly, the photoelectrochromic material is present in a form dispersed in various solvents, and a coating film can be formed through dispersion and mixing thereof.

Next, at least one of organic particles and inorganic particles is dispersed in the organic-inorganic hybrid binder (S30).

Based on the previously prepared organic-inorganic hybrid binder, organic and inorganic nanoparticles may be composited. The organic particles may include nanoparticles that can exist as particles without dissolution and dissociation in a solvent and have chemical resistance. The inorganic particles may include aqueous and organic dispersed silica nanosols. Such organic particles and inorganic particles may be surface-treated using organic silane, if necessary.

In order to improve the hardness of the coating film, as in the previous step, when synthesizing siloxane, the additional input content of trivalent and tetravalent silane can be increased rather than monovalent and divalent silane, and the content of organic particles and inorganic particles can be increased for better coating hardness. It is possible to control the amount ratio between the nanoparticles that are stretched and filled.

Nanoparticles such as silica of silica sol are in the form of particles having a particle size in the range of 5 to 100 nm, and may be included up to 40% by weight of the total solid content of the organic-inorganic hybrid binder. The organic and inorganic particles may have the same size, or may be composed of different sizes of nanoparticles. If the size of the nanoparticles is varied, the mobility of ions can be controlled by controlling the internal density of the photoelectrochromic layer. .

Such an organic-inorganic hybrid binder is based on a siloxane resin, and it is possible to induce convergence of the nanoparticles and the siloxane resin by controlling the particle size and weight ratio of the organic nanoparticles and inorganic nanoparticles, thereby controlling the density in the coating film and , it is possible to control the ion mobility between the electrodes inside the cell constituting the photoelectrochromic device.

Since the organic-inorganic hybrid binder prepared in this way serves to form a coating film without cracks from a sub-micrometer to a thickness of several tens of micrometers, it is mixed with a photoelectrochromic material and applied on an electrode, followed by light in the 300 to 400 nm UV region. or thermally cured at 100 to 150° C. to form a coating film, and this coating film may be a photoelectric discoloration layer. When the UV region is less than 300 nm or more than 400 nm during photo-curing, not only does it take a lot of time to photo-curing, but there is a concern about modifying the physical properties of the coating film. When thermal curing is less than 100 ° C, there is a disadvantage in that it takes a lot of time to completely cure into a coating film, and when it exceeds 150 ° C, there is a concern that it will be an inefficient process due to unexpected chemical reactions due to high temperature.

In particular, in the case of a discoloration coating film formed by high-temperature heat treatment of an inorganic-based coating solution applied to existing photoelectrochromic devices, it is impossible to form a thick film, so there is a limit to increasing color transmittance, and process prices increase when a high-temperature heat treatment process such as deposition is performed. As a result, there was no choice but to limit the market competitiveness. In contrast, the organic-inorganic hybrid binder prepared according to the present invention can form a thick film from a thin film through a low-temperature wet process, so it has advantages of not only price competitiveness but also increasing the efficiency of color transmittance through the thick film.

In addition, since the siloxane structure of the organic-inorganic hybrid binder has excellent heat resistance and chemical resistance compared to organic materials, it can be used in polar solvents such as water and alcohol, as well as neutral solvents such as cellosolves and acetates, as well as ketones such as toluene and acetone. It exhibits chemical durability against various solvents, ranging from non-polarity, because it forms the same siloxane structure as inorganic materials. As it is possible to form a more dense film through the curing reaction of a heat curing group or photo curing group substituted based on this siloxane structure, it is soluble in contact and penetration of various organic solvents and ions that make up the electrolyte solution widely used in energy devices. to have long-term stability.

In another aspect, the present invention relates to a photoelectrochromic device 100 including an organic-inorganic hybrid binder, as shown in FIG.

Referring to FIG. 1 , it can be seen that the photoelectrochromic device 100 including the photoelectrochromic layer 170 using the organic-inorganic hybrid binder of the present invention shows a structural appearance. The photoelectrochromic element 100 includes a first electrode 130, a second electrode 140 facing the first electrode 130, and an electrolyte layer disposed between the first electrode 130 and the second electrode 140 ( 150), the first photoelectric color change layer 160 disposed between the first electrode 130 and the electrolyte layer 150 and the second photoelectric color change layer disposed between the second electrode 140 and the electrolyte layer 150 ( 170), characterized in that it is configured to include.

The first substrate 110 and the second substrate 120 provide a space in which the first electrode 130 and the second electrode 140 can be deposited or coated.

The first electrode 130 and the second electrode 140 are electrically conductive and transparent, and may be deposited or coated on the first substrate 110 and the second substrate 120 to form thin films or films. can A positive voltage may be applied to the first electrode 130 and a negative voltage may be applied to the second electrode 140 .

In the case of the first electrode 130 and the second electrode 140, indium tin oxide (ITO), transparent conductive oxide (TCO), conductive polymer, metal grid, and carbon nanotube (CNT) are used. nano tube), graphene, and carbon nanowires.

The electrolyte layer 150 is disposed between the first electrode 130 and the second electrode 140 and may be disposed on the first photoelectrochromic layer 160 .

The first photoelectric discoloration layer 160 is disposed on the first electrode 130, and a conductive material capable of storing polar ions opposite to those involved in photoelectric discoloration may be used, and Ni(OH) ₂ , Cr ₂ O ₃ , MnO ₂ , RH ₂ O ₃ , CoOx, Ir(OH)x, Fe ₂ O ₃ or V ₂ O ₅ .

The second photoelectric color change layer 170 may be disposed on the electrolyte layer 150 and change color as an electric field is applied.

The photoelectrochromic material may include an oxidative or reductive colorant. Oxidative discoloration materials include vanadium (V) oxide, chromium (Cr) oxide, manganese (Mn) oxide, iron (Fe) oxide, cobalt (Co) oxide, nickel (Ni) oxide, rhodium (Rh) oxide, and iridium (Ir) oxide. It may be any one or more of oxides. The reducing discoloration material may be any one or more of titanium (Ti) oxide, copper (Cu) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, niobium (Nb) oxide, and tantalum (Ta) oxide. In addition, photoelectrochromic materials include organic materials such as viologen, organometallic pigments such as Prussian blue, and organic materials such as perylene dimide, in addition to oxidative or reductive discoloration materials. material can also be used.

As described above, the organic-inorganic hybrid binder for forming the first photoelectric discoloration layer 160 and the second photoelectric discoloration layer 170 has a siloxane structure, and thus has superior light resistance to ultraviolet rays compared to organic materials, along with heat resistance and chemical resistance. And, by applying heat or photocurable trivalent silane capable of outdoor stability, it can be applied to photoelectrochromic devices requiring long-term outdoor exposure. Curable trivalent silanes capable of satisfying these physical properties are divalent and trivalent organic silanes having an alicyclic epoxy group, which can be applied to the synthesis of siloxane to improve the light resistance of the coating film constituting the photoelectrochromic layer.

Hereinafter, an embodiment of the present invention will be described in more detail. However, the following examples are merely illustrative to aid understanding of the present invention, and the scope of the present invention is not limited thereby.

<Example 1> Formation of photocuring coating film

After mixing methacrylpropyltrimethoxysilane (MPTMS), a photocurable trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl, 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and benzyl thyme methyl ketone (BDK) photoinitiator was added at 1.5% of the total weight of MPTMS silane, and finally the presence or absence of photocurable type A hybrid siloxane binder was prepared.

Nickel oxide (NiO, 20nm) nanoparticles are mixed with the prepared binder in a weight ratio of 5:95 to form a coating film through bar coating, and after photocuring using a UV lamp in the 365nm region, the final coating film is 0.5㎛, 2 It was formed by thickness of ㎛, 5㎛, and 15㎛.

<Example 2> Formation of photocuring coating film

After mixing methacrylpropyltrimethoxysilane (MPTMS), a photocurable trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl, 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and benzyl thyme methyl ketone (BDK) photoinitiator was added at 1.5% of the total weight of MPTMS silane, and finally the presence or absence of photocurable type A hybrid siloxane binder was prepared.

After mixing the prepared binder with 40nm silica sol in a weight ratio of 9.5: 0.5, nickel oxide (NiO, 20nm) nanoparticles were mixed in a weight ratio of 5: 95 to form a coating film through bar coating, but in the 365nm region After photocuring using a UV lamp, a final coating film was formed for each thickness of 0.5 μm, 2 μm, 5 μm, and 15 μm.

<Example 3> Formation of photocuring coating film

After mixing methacrylpropyltrimethoxysilane (MPTMS), a photocurable trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl, 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and benzyl thyme methyl ketone (BDK) photoinitiator was added at 1.5% of the total weight of MPTMS silane, and finally the presence or absence of photocurable type A hybrid siloxane binder was prepared.

40nm silica sol was mixed with the prepared binder at a weight ratio of 9:1, and nickel oxide (NiO, 20nm) nanoparticles were mixed at a weight ratio of 5:95 to form a coating film through bar coating, but UV in the 365nm region After photocuring using a lamp, a final coating film was formed for each thickness of 0.5 μm, 2 μm, 5 μm, and 15 μm.

<Example 4> Formation of photocuring coating film

After mixing methacrylpropyltrimethoxysilane (MPTMS), a photocurable trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl, 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and benzyl thyme methyl ketone (BDK) photoinitiator was added at 1.5% of the total weight of MPTMS silane, and finally the presence or absence of photocurable type A hybrid siloxane binder was prepared.

40nm silica sol was mixed with the prepared binder in a weight ratio of 8.5: 1.5, and then nickel oxide (NiO, 20nm) nanoparticles were mixed in a weight ratio of 5: 95 to form a coating film through bar coating, but UV in the 365nm region After photocuring using a lamp, a final coating film was formed for each thickness of 0.5 μm, 2 μm, 5 μm, and 15 μm.

<Example 5> Formation of a thermal curing coating film

After mixing epoxycyclohexylethyltrimethoxysilane (ECETMS), a thermosetting trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl , 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and B5428 (TCI) thermal initiator was added at 1.5% of the total weight of ECETMS silane. A hybrid siloxane binder was prepared.

Nickel oxide (NiO, 20 nm) nanoparticles are mixed with the prepared binder at a weight ratio of 5:95 to form a coating film through bar coating, and after thermal curing at 130 ° C. for 10 minutes, the final coating film is 0.5 μm, 2 μm, It was formed by thickness of 5㎛ and 15㎛.

<Example 6> Formation of a thermal curing coating film

After mixing epoxycyclohexylethyltrimethoxysilane (ECETMS), a thermosetting trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl , 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and B5428 (TCI) thermal initiator was added at 1.5% of the total weight of ECETMS silane. A hybrid siloxane binder was prepared.

40 nm silica sol was mixed with the prepared binder in a weight ratio of 9.5: 0.5, and then nickel oxide (NiO, 20 nm) nanoparticles were mixed in a weight ratio of 5: 95 to form a coating film through bar coating, but at 130 ° C. After thermal curing for minutes, final coating films were formed for each thickness of 0.5 μm, 2 μm, 5 μm, and 15 μm.

<Example 7> Formation of a thermal curing coating film

After mixing epoxycyclohexylethyltrimethoxysilane (ECETMS), a thermosetting trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl , 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and B5428 (TCI) thermal initiator was added at 1.5% of the total weight of ECETMS silane. A hybrid siloxane binder was prepared.

40nm silica sol was mixed with the prepared binder in a weight ratio of 8: 2, and then nickel oxide (NiO, 20nm) nanoparticles were mixed in a weight ratio of 5: 95 to form a coating film through bar coating, but at 130 ℃ 10 After thermal curing for minutes, final coating films were formed for each thickness of 0.5 μm, 2 μm, 5 μm, and 15 μm.

<Example 8> Formation of a thermal curing coating film

After mixing epoxycyclohexylethyltrimethoxysilane (ECETMS), a thermosetting trivalent silane, and propyltrimethoxysilane (PTMS), an alkyl trivalent silane, in a molar ratio of 8:2, hydrochloric acid, an acid catalyst, was added (0.01n HCl , 1.5 mol), and after 24 hours of room temperature reaction, the alcohol generated was replaced with ethyl cellosolve (EC), and B5428 (TCI) thermal initiator was added at 1.5% of the total weight of ECETMS silane. A hybrid siloxane binder was prepared.

40 nm silica sol was mixed with the prepared binder in a weight ratio of 7: 3, and then nickel oxide (NiO, 20 nm) nanoparticles were mixed in a weight ratio of 5: 95 to form a coating film through bar coating, but at 130 ℃ 10 After thermal curing for minutes, final coating films were formed for each thickness of 0.5 μm, 2 μm, 5 μm, and 15 μm.

<Comparative Example 1> Formation of a coating film that is not photocured / thermally cured using only tetravalent silane

Hydrochloric acid, an acid catalyst, was added to tetraethylorthosilicate (TEOS), a tetravalent silane (0.01n HCl, 2 mol relative to the total amount of TEOS input), and water and alcohol generated after a 24-hour stirring reaction at room temperature were mixed with ethyl cellosolve ( After solvent replacement with EC), a silicate solution of tetravalent silane TEOS alone was prepared, and after solvent replacement of water and alcohol as reaction dispersions with ethyl cellosolve (EC), a final ethyl cellosolve (EC) dispersed silicate solution was prepared.

The prepared silicate solution was mixed with nickel oxide (NiO, 20 nm) nanoparticles in a weight ratio of 5: 95 to form a coating film with a thickness of 0.5 μm, 2 μm, 5 μm, and 15 μm through bar coating.

<Test Example 1>

In this test example, the visible light transmittance of the coating film according to Examples 1 to 8 and Comparative Example 1 (ITO deposited PET film), chemical resistance by solvent (H2O-IPA-EC-MEK-Toluene), adhesion, presence or absence of cracks by coating film thickness (0.5㎛, 2㎛, 5㎛, 15㎛) was analyzed, and the evaluation conditions for this are as follows.

(1) Transmittance: 400 to 800 nm total light transmittance (0.5 μm coating film)

(2) Chemical resistance: Peeling and swelling after 48 hr dipping for each solvent Visual observation and optical microscope observation (0.5㎛ coating film)

(3) Adhesion: Adhesion through cross-cut test (0.5㎛ coating film)

(4) Hardness: Pencil hardness test (5㎛ coating film)

(5) Cracks: Optical microscope observation (by coating film thickness)

The results according to this are shown in Table 1 below.

item Example
One Example
2 Example
3 Example
4 Example
5 Example
6 Example
7 Example
8 comparative example
One permeability 50 50.5 51 51 50 50.5 51 51 51 chemical resistance H ₂ O ◎ ◎ ◎ ○ ◎ ◎ ◎ ○ △ IPA ◎ ◎ ◎ ○ ◎ ◎ ◎ ○ △ EC ◎ ◎ ◎ ○ ◎ ◎ ◎ ○ △ MEK ◎ ◎ ◎ ○ ◎ ◎ ◎ ○ △ Toluene ◎ ◎ ◎ ○ ◎ ◎ ◎ ○ △ adhesion 5B 5B 5B 4B 5B 5B 5B 4B 2B Hardness 2H 3H 3H 2H 2H 3H 4H 2H H coating
By thickness
crack 0.5㎛ ◎ ◎ ◎ ○ ◎ ◎ ◎ ○ △ 2㎛ ◎ ◎ ◎ ○ ◎ ◎ ◎ ○ × 5㎛ ◎ ◎ ◎ △ ◎ ◎ ◎ △ × 15㎛ ◎ ◎ ◎ △ ◎ ◎ ◎ ○ × ◎: Excellent, ○: Good, △: Normal, ×: Bad

Referring to Table 1, in the case of the organic-inorganic hybrid binders prepared based on trivalent silane in Examples 1 to 8, it can be seen that the overall physical properties are excellent compared to the binder of tetravalent silane alone as in Comparative Example 1, Applicability as a binder for photoelectrochromic device application can be confirmed.

It can be seen that the hardness of the coating film slightly increases as the content of the silica nanoparticles in the silica sol increases, whereas when the particle content is added in an excessively large amount, the adhesion, chemical resistance and hardness decrease due to the decrease in the content of the binder. seemed Through this, it can be seen that it is important to properly control the size and amount of nanoparticles.

As a result of the test for the presence of cracks by coating film thickness, in the case of Comparative Example 1, only a coating film of 0.5 μm or less was able to form a film without cracks, and it was found that cracks easily occurred in the coating film of 2 μm or more due to the brittleness of the film.

In comparison, in the case of the organic-inorganic hybrid binder, it was possible to form a stable film without cracks even at 15 μm, and accordingly, the organic-inorganic hybrid binder based on the trivalent silane of the present invention can be applied to a coating film in various thicknesses from thin to thick films. And, since it expresses excellent physical properties in terms of chemical resistance, adhesion, hardness, and crack presence, it has the advantage of being applicable as a binder in a rigid photoelectric discoloration device.

In summary, the present invention provides an organic-inorganic hybrid binder having a siloxane structure that is mixed with a photoelectrochromic material and applied on an electrode and then photocured in a 300 to 400 nm UV region or thermally cured at 100 to 150 ° C. It is characterized by stably dispersing and mixing the discoloration material to increase the discoloration efficiency.

According to this feature, by introducing a substituent capable of inducing bonding of the organic-inorganic hybrid binder with the first substrate 110 and the second substrate 120, compatibility with the photoelectrochromic material can be promoted, and chemical Through bonding, adhesion to the first substrate 110 and the second substrate 120 may be induced, thereby securing adhesion to the substrate.

In addition, in the case of a conventional inorganic deposition film or inorganic material-based coating film, there is a lack of flexibility and restrictions on mechanical change, so it is difficult to apply to a flexible substrate with a curvature, and defects such as pinholes on the surface of the coating film exist, resulting in a photoelectrochromic device. Unlike the long-term stability and color reproducibility that deteriorated over time, the flexibility and mechanical properties of the coating film can be supplemented through the organic-inorganic hybrid binder of the present invention, and the material and composition of the photoelectrochromic layer 170 can be controlled. Since the modulus of elasticity of the structure of the photoelectrochromic device 100 can be controlled, it can have sufficient flexibility.

In the photoelectrochromic device 100 directly exposed to outdoor ultraviolet rays, a problem in which organic materials are decomposed when exposed to ultraviolet rays for a long time needs to be supplemented with inorganic materials, so a light-resistant functional group is introduced into an organic-inorganic hybrid binder. By doing so, it is possible to secure thick film coating and wet processability that inorganic materials cannot express while securing light resistance such as ultraviolet rays for the outdoors.

Therefore, the organic-inorganic hybrid binder of the present invention has excellent chemical resistance and heat resistance inherent in siloxane, and can exhibit high stability against chemical resistance and heat resistance against organic solvents and ions based on an additional high degree of curing. Since the internal porosity and surface properties of the photoelectrochromic layer 170 can be adjusted, it is expected that the application can be expanded to binder materials for electrolytes in energy devices.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are intended to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100: photoelectrochromic element
110: first substrate
120: second substrate
130: first electrode
140: second electrode
150: electrolyte layer
160: first photoelectric chromic layer
170: second photoelectric chromic layer

Claims (5)

Reacting a trivalent alkoxy silane having a photocurable or thermocurable functional group with at least one organic silane having a polar group of 1 to 4 at room temperature under an acid or base catalyst, followed by a reflux reaction at 70 to 80 ° C; and
Preparing an organic-inorganic hybrid binder having a siloxane structure by replacing the alcohol generated through the reaction with a solvent different from the alcohol and then mixing an initiator,
The organic-inorganic hybrid binder is mixed with a photoelectric color change material and applied on an electrode and then photocured in a 300 to 400 nm UV region or thermally cured at 100 to 150 ° C. A method for preparing a hybrid binder. According to claim 1,
Dispersing at least one of organic particles and inorganic particles in the organic-inorganic hybrid binder. According to claim 1,
The photoelectric discoloration material includes an oxidative discoloration material or a reductive discoloration material,
The oxidative discoloration material may include vanadium (V) oxide, chromium (Cr) oxide, manganese (Mn) oxide, iron (Fe) oxide, cobalt (Co) oxide, nickel (Ni) oxide, rhodium (Rh) oxide, and iridium ( Ir) at least one of the oxides,
Characterized in that the reductive discoloration material is at least one of titanium (Ti) oxide, copper (Cu) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, niobium (Nb) oxide, and tantalum (Ta) oxide, A method of manufacturing an organic-inorganic hybrid binder for a photoelectric color change layer of a photoelectric color change device. Under an acid or base catalyst, a trivalent alkoxy silane having a photocurable or thermocurable functional group and at least one organic silane having a polar group of 1 to 4 are reacted at room temperature and reflux at 70 to 80 ° C. An organic-inorganic hybrid binder having a siloxane structure is formed by mixing an initiator after replacing alcohol with a solvent different from the alcohol,
The organic-inorganic hybrid binder is mixed with a photoelectric discoloration material and applied on an electrode, and then photocured in a 300 to 400 nm UV region or thermally cured at 100 to 150 ° C to form a coating film. Organic-inorganic hybrid binder for photoelectrochromic layer. a first electrode;
a second electrode facing the first electrode;
an electrolyte layer disposed between the first electrode and the second electrode;
a first photoelectric color change layer disposed between the first electrode and the electrolyte layer; and
Including; a second photoelectric color change layer disposed between the second electrode and the electrolyte layer,
The first photoelectric color change layer and the second photoelectric color change layer,
Under an acid or base catalyst, a trivalent alkoxy silane having a photocurable or thermocurable functional group and at least one organic silane having a polar group of 1 to 4 are reacted at room temperature and produced through a reflux reaction at 70 to 80 ° C. an organic-inorganic hybrid binder having a siloxane structure formed by replacing alcohol with a solvent different from the alcohol and then mixing an initiator; and
Photoelectrochromic material; formed by mixing,
Photo-curing in the 300 to 400 nm UV region or thermally curing at 100 to 150 ° C., a photoelectric discoloration element.

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