KR20150076778A - A electrochromic device and methods of driving the same - Google Patents

Abstract

According to the present invention, an electrochromic device comprises: a lower electrochromic layer including lower metal oxide particles and lower electrochromic particles provided on each lower metal oxide particle; and an upper electrochromic layer provided on an electrolyte, and including upper metal oxide particles and upper electrochromic particles provided on each lower metal oxide particle. The metal oxide particles may comprise the first lower metal oxide particles and the second lower metal oxide particles. The upper metal oxide particles may comprise the first upper metal oxide particles and the second upper metal oxide particles.

Description

[0001] The present invention relates to an electrochromic device and a method of driving the same,

The present invention relates to an electrochromic device, and more particularly, to an electrochromic device of an electrochromic device and an operation method thereof.

BACKGROUND ART Liquid crystal displays (LCDs) and organic light emitting devices (OLEDs) are widely used as information displays. The devices realize color by transmitting light of a self light source through a color filter or by mixing light emitted according to current flow in the material itself.

Recently, electrochromic devices have been applied to optical shutters, reflective displays, automotive discoloration mirrors, and smart windows. An electrochromic device is a device that changes color by an electrochemical reaction. In the electrochromic device, when a potential difference is generated by an external electrical stimulus, ions or electrons contained in the electrolyte migrate into the electrochromic layer and an oxidation / reduction reaction occurs. The color of the electrochromic device is changed by the redox reaction of the electrochromic layer. Reduced coloring materials are substances that are colored when a cathodic reaction occurs and are discolored when an anodic reaction occurs. The oxidative discoloring substance means a substance which is colored when it is oxidized and decolorized when it is a reducing reaction.

An object of the present invention is to provide an electrochromic device having improved electrochromic rate.

Another object of the present invention is to provide a method for easily driving an electrochromic device.

The problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

The present invention relates to an electrochromic device and a driving method thereof. An electrochromic device according to the concept of the present invention includes a lower substrate; A lower electrode on the lower substrate; A lower electrochromic layer disposed on the lower electrode, the lower electrochromic layer comprising lower metal oxide particles and lower electrochromic particles provided on the respective metal oxide particles, the lower metal oxide particles are mixed with the first lower metal oxide particles and Including second bottom metal oxide particles; An electrolyte provided on the lower electrochromic layer; An upper electrochromic layer provided on the electrolyte, the upper electrochromic layer comprising upper metal oxide particles and upper electrochromic particles provided on the respective metal oxide particles, the upper metal oxide particles comprising first upper metal oxide particles and Comprising two upper metal oxide particles; And an upper electrode on the upper electrochromic layer.

According to an embodiment, the first lower metal oxide particles include the same material as the first upper metal oxide particles, and the second upper metal oxide particles include the same material as the second upper metal oxide particles .

According to an embodiment, the upper metal oxide particles may have the same composition ratio as the lower metal oxide particles.

According to an embodiment, the electrochromic potential of the lower electrochromic layer may be the same as the electrochromic potential of the upper electrochromic layer.

A method of manufacturing an electrochromic device according to the concept of the present invention is an electrochromic device comprising a first electrode, a first electrochromic layer, an electrolyte, a second electrochromic layer, and an upper electrode sequentially stacked on a substrate, Applying a reference voltage to the first electrochromic layer and applying a first voltage to the second electrochromic layer to display a first color; Applying a second voltage to the second electrochromic layer to display a second color; And applying the reference voltage to the second electrochromic layer to display a transparent color.

According to an embodiment, the magnitude of the first voltage may be equal to the magnitude of the second voltage.

According to an embodiment of the present invention, the method further comprises: displaying a mixed color by applying a third voltage to the second electrochromic layer, wherein the first electrochromic layer exhibits a third color upon application of the third voltage, The second electrochromic layer may exhibit a fourth color, and the mixed color may be realized by mixing the third color and the fourth color.

According to an embodiment, the third voltage has a value between the first voltage and the reference voltage, the third color has a lower saturation than the first color, and the fourth color is lower than the second color You can have saturation.

According to an embodiment, the first electrochromic layer may include first metal oxide particles, second metal oxide particles, and first electrochromic particles, wherein the first electrochromic particles include a first metal oxide particle Particles and each of the second metal oxide particles.

According to an embodiment, the second electrochromic layer may include third metal oxide particles, fourth metal oxide particles, and second electrochromic particles, wherein the second electrochromic particles include a third metal oxide particle Particles and each of the fourth metal oxide particles.

According to an embodiment of the present invention, the method may further include applying a third voltage and a fourth voltage to the second electrochromic layer by alternating current to display a mixed color, wherein the difference between the reference voltage and the third voltage is May be the same as the difference of the reference voltage.

According to the present invention, the electrochromic layer may comprise first metal oxide particles, second metal oxide particles, and electrochromic particles. The electrochromic potential of the electrochromic layer can be controlled by adjusting the kind and content ratio of the metal oxide particles contained in the electrochromic layer. For example, the upper electrochromic layer may have the same or similar electrochromic potential as the lower electrochromic layer. Any one of the electrochromic layers can receive a reference voltage. The voltage applied to the other electrochromic layer is controlled to enable the electrochromic device to operate. Thus, the display color of the electrochromic device can be easily controlled.

According to the present invention, the electrochromic device can be easily operated.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding and assistance of the invention, reference is made to the following description, taken together with the accompanying drawings,
1 is a cross-sectional view illustrating an electrochromic device according to an embodiment of the present invention.
FIG. 2 is an enlarged view of the region II in FIG.

In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It will be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof. Those of ordinary skill in the art will understand that the concepts of the present invention may be practiced in any suitable environment.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. As used herein, the terms 'comprises' and / or 'comprising' mean that the stated element, step, operation and / or element does not imply the presence of one or more other elements, steps, operations and / Or additions.

When a film (or layer) is referred to herein as being on another film (or layer) or substrate it may be formed directly on another film (or layer) or substrate, or a third film Or layer) may be interposed.

 Although the terms first, second, third, etc. have been used in various embodiments herein to describe various regions, films (or layers), etc., it is to be understood that these regions, do. These terms are merely used to distinguish any given region or film (or layer) from another region or film (or layer). Thus, the membrane referred to as the first membrane in one embodiment may be referred to as the second membrane in another embodiment. Each embodiment described and exemplified herein also includes its complementary embodiment. Like numbers refer to like elements throughout the specification.

The terms used in the embodiments of the present invention may be construed as commonly known to those skilled in the art unless otherwise defined.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Hereinafter, the electrochromic device according to the concept of the present invention will be described.

FIG. 1 is a cross-sectional view illustrating an electrochromic device according to an embodiment of the present invention. FIG. 2 is an enlarged view of the region II of FIG.

1, an electrochromic device 1 according to the present invention includes a lower substrate 100, a lower electrode 200, a lower electrochromic layer 300, an electrolyte 400, an upper electrochromic layer 500, An upper electrode 600, and an upper substrate 700. The lower substrate 100 may be flexible. The lower substrate 100 may be a transparent substrate. A lower electrode 200 may be provided on the lower substrate 100. The lower electrode 200 may include a transparent conductive oxide (TCO).

Referring to FIG. 2 together with FIG. 1, a lower electrochromic layer 300 may be provided on the lower electrode 200. The lower electrochromic layer 300 may include lower metal oxide particles 310 and lower electrochromic particles 320. The lower metal oxide particles 310 may include at least one or more kinds of transparent conductive oxides. For example, the lower metal oxide particles 310 may include first lower metal oxide particles 311 and second lower metal oxide particles 312. The first lower metal oxide particles 311 may include any one of TiO ₂ , antimony (Sn) -doped tin oxide (SnO 2), and zinc oxide (ZnO) May include another one. For example, the first lower metal oxide particles 311 may comprise TiO ₂ and the second lower metal oxide particles 312 may comprise antimony (Sb) doped tin oxide (SnO).

Lower electrochromic particles 320 may be provided on each of the lower metal oxide particles 310. The lower electrochromic particles 320 may be fixed to the surface of the lower metal oxide particles 310. The lower electrochromic particles 320 may be selected from the group consisting of viologen, poly 3,4-ethylenedioxythiophene (PEDOT) WO ₃ , NiO, MoO _{3 ,} and / or Nb ₂ O ₅ .

Referring again to FIG. 1, an electrolyte 400 may be provided on the lower electrochromic layer 300. The electrolyte 400 can transfer ions between the lower electrochromic layer 300 and the upper electrochromic layer 500.

An upper electrochromic layer 500 may be provided on the electrolyte 400. The upper electrochromic layer 500 may include upper metal oxide particles 510 and upper electrochromic particles 520. Upper metal oxide particles 510 may include first upper metal oxide particles 511 and second upper metal oxide particles 512. The first upper metal oxide particles 511 and the second upper metal oxide particles 512 are formed of the first lower metal oxide particles 311 and the second lower metal oxide particles 312 shown in FIG. May be the same or similar. For example, the first upper metal oxide particles 511 may include any one of TiO ₂ , antimony (Sb) -doped tin oxide (SnO), and zinc oxide (ZnO) 512 may include another one. The upper metal oxide particles 510 may comprise the same material as the lower metal oxide particles 310. For example, the first upper metal oxide particles 511 may comprise the same material as the first lower metal oxide particles 311. The second upper metal oxide particles 512 may include the second lower metal oxide particles 311, May include the same material as the particles 312. The upper metal oxide particles 510 may have the same composition ratio as the lower metal oxide particles 310

Upper electrochromic particles 520 may be provided on each of the upper metal oxide particles 510. The upper electrochromic particles 520 may have the same electrochromic potential as the lower electrochromic particles 320. The upper metal oxide particles 520 may comprise the same material as the lower electrochromic particles 320 described above, for example, a violon. As another example, the upper electrochromic particles 520 may comprise a material having an electrical potential that is the same or similar to the lower electrochromic particles 320. The upper electrochromic layer 500 may have a different color from the lower electrochromic layer 300.

The upper electrode 600 and the upper substrate 700 may be sequentially stacked on the upper electrochromic layer 500. The upper electrode 600 may include a transparent conductive oxide. The upper substrate 700 may be flexible.

The upper surface of the upper substrate 700 may be a display surface. In this case, the saturation of the color realized by the upper electrochromic layer 500 may be lower than the saturation of the color realized by the lower electrochromic layer 300. When the lower surface of the lower substrate 100 is a display surface, the color saturation of the lower electrochromic layer 300 may be lower than that of the color of the upper electrochromic layer 500.

The operation principle of the electrochromic device 1 according to the present invention is as follows. Hereinafter, the case where the upper surface of the upper substrate 700 is a display surface will be described. However, even when the lower surface of the lower substrate 100 is the display surface, the electrochromic device 1 can operate by the same or similar principle.

A reference voltage may be applied to the lower electrochromic layer 300 through the lower electrode 200. In the driving process of the electrochromic device 1, the voltage applied to the lower electrochromic layer 300 may be constant.

A first voltage may be applied to the upper electrochromic layer 500 through the upper electrode 600. The difference between the first voltage and the reference voltage may be equal to or greater than the value of the electrochromic potential of the lower electrochromic layer 300. The lower electrochromic layer 300 may exhibit a first color and the upper electrochromic layer 500 may exhibit a transparent color. By the first color represented by the lower electrochromic layer 300, the electrochromic device 1 can realize the first color. As the lower electrochromic layer 300 further includes the second lower metal oxide particles 312, the value of the first voltage can be adjusted. By adjusting the ratio of the first lower metal oxide particles 311 and the second lower metal oxide particles 312, the value of the first voltage can be adjusted. The first voltage may be less than the reference voltage.

A second voltage may be applied to the upper electrochromic layer 500. The second voltage may be greater than the reference voltage. The upper electrochromic layer 500 may exhibit a second color, and the lower electrochromic layer 300 may exhibit a transparent color. Thus, the electrochromic device 1 can realize the second color. The second voltage may have the same magnitude as the first voltage. For example, the difference between the reference voltage and the first voltage may be equal to the difference between the second voltage and the reference voltage. For example, when a voltage of -3 V versus the lower electrochromic layer 300 is applied to the upper electrochromic layer 500, the electrochromic device 1 may exhibit the first color. When a voltage of 3 V is applied to the upper electrochromic layer 500 with respect to the lower electrochromic layer 300, the electrochromic device 1 may exhibit a second color. As the upper electrochromic layer 500 further includes the second upper metal oxide particles 512, the value of the second voltage can be adjusted. For example, by adjusting the material or content ratio of the first upper metal oxide particles 511 and the second upper metal oxide particles 512, the value of the second voltage can be adjusted. Thus, the display color of the electrochromic device 1 can be easily controlled.

A reference voltage may be applied to the upper electrochromic layer 500. For example, the voltage applied to the upper electrochromic layer 500 may be the same as the voltage applied to the lower electrochromic layer 300. Each of the upper electrochromic layer 500 and the lower electrochromic layer 300 may exhibit a transparent color. Thus, the electrochromic device 1 can realize a transparent color.

A method in which the electrochromic device 1 exhibits a mixed color will be described.

A third voltage or a fourth voltage may be applied to the upper electrochromic layer 500. The third voltage may have the same magnitude as the fourth voltage. For example, the difference between the reference voltage and the third voltage may be the same as the difference between the fourth voltage and the reference voltage. The third voltage may have a value between the first voltage and the reference voltage. The fourth voltage may have a value between the reference voltage and the second voltage. When a third voltage is applied to the upper electrochromic layer 500, the color indicated by the electrochromic device 1 is a color that the electrochromic device 1 has when the fourth voltage is applied to the upper electrochromic layer 500 And may be the same or similar to the color to be displayed. For example, the lower electrochromic layer 300 may exhibit a third color having a lower saturation than the first color. The upper electrochromic layer 500 may realize a fourth color having a lower saturation than the second color. Thus, the electrochromic device 1 can display the mixed color of the third color and the fourth color. For example, the mixed color may be black.

As another example, the third voltage and the fourth voltage may be alternately applied to the upper electrochromic layer 500, so that the electrochromic device 1 may exhibit the mixed color. In this case, the rate at which the electrochromic device 1 is changed from a mixed color to another color can be improved. According to the present invention, various mixed colors of the first and second colors can be displayed on the electrochromic device 1 by adjusting the voltage applied to the upper electrochromic layer 500.

According to the present invention, the voltage applied to the upper electrochromic layer 500 is controlled to enable the electrochromic device 1 to operate. Alternatively, a reference voltage may be applied to the upper electrochromic layer 500. In this case, the driving of the electrochromic device 1 can be controlled by adjusting the voltage applied to the lower electrochromic layer 300. The electrochromic device 1 of the present invention can be easily driven.

Claims (11)

A lower substrate;
A lower electrode on the lower substrate;
A lower electrochromic layer disposed on the lower electrode, the lower electrochromic layer comprising lower metal oxide particles and lower electrochromic particles provided on the respective metal oxide particles, the lower metal oxide particles are mixed with the first lower metal oxide particles and Including second bottom metal oxide particles;
An electrolyte provided on the lower electrochromic layer;
An upper electrochromic layer provided on the electrolyte, the upper electrochromic layer comprising upper metal oxide particles and upper electrochromic particles provided on the respective metal oxide particles, wherein the upper metal oxide particles comprise a first upper metal oxide particle and a second upper metal oxide particle, Comprising two upper metal oxide particles; And
And an upper electrode on the upper electrochromic layer.
The method according to claim 1,
Wherein the first lower metal oxide particles comprise the same material as the first upper metal oxide particles,
Wherein the second upper metal oxide particles comprise the same material as the second upper metal oxide particles.
3. The method of claim 2,
Wherein the upper metal oxide particles have the same composition ratio as the lower metal oxide particles.
The method according to claim 1,
Wherein the electrochromic potential of the lower electrochromic layer is the same as the electrochromic potential of the upper electrochromic layer.
A method of driving an electrochromic device comprising a first electrode, a first electrochromic layer, an electrolyte, a second electrochromic layer, and an upper electrode sequentially stacked on a substrate,
A reference voltage is applied to the first electrochromic layer,
Applying a first voltage to the second electrochromic layer to display a first color;
Applying a second voltage to the second electrochromic layer to display a second color; And
And applying the reference voltage to the second electrochromic layer to display a transparent color.
6. The method of claim 5,
Wherein the magnitude of the first voltage is equal to the magnitude of the second voltage.
6. The method of claim 5,
And applying a third voltage to the second electrochromic layer to display a mixed color,
Wherein the first electrochromic layer shows a third color and the second electrochromic layer shows a fourth color by application of the third voltage and the mixed color is a mixture of the third color and the fourth color Wherein the electrochromic device comprises a first electrode and a second electrode.
8. The method of claim 7,
Wherein the third voltage has a value between the first voltage and the reference voltage.
Wherein the third color has lower saturation than the first color and the fourth color has lower saturation than the second color.
6. The method of claim 5,
Wherein the first electrochromic layer comprises first metal oxide particles, second metal oxide particles, and first electrochromic particles, wherein the first electrochromic particles are in contact with each of the first metal oxide particles and each And fixed on the second metal oxide particles.
6. The method of claim 5,
Wherein the second electrochromic layer comprises third metal oxide particles, fourth metal oxide particles, and second electrochromic particles, wherein the second electrochromic particles are in contact with each of the third metal oxide particles and each And fixed on the fourth metal oxide particles.
6. The method of claim 5,
And applying a third voltage and a fourth voltage to the second electrochromic layer by alternating current to display a mixed color,
Wherein the difference between the reference voltage and the third voltage is equal to the difference between the fourth voltage and the reference voltage.

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