A fully thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance and a method for preparing the same

Abstract

A full-thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance and a method for preparing the same, which relates to a full-thin-film electrochromic device and a method for preparing the same. The purpose of the present invention is to solve the problems in the prior art that full-thin-film electrochromic devices are difficult to independently regulate visible light and near-infrared light transmittance, have weak regulation capabilities and poor cycle stability, and have only two regulation modes. A full-thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance comprises a transparent bottom electrode, an ion storage layer, an ion conduction layer, an electrochromic layer capable of independently regulating visible light and near-infrared light transmittance, and a transparent top electrode, wherein the electrolyte is water or water vapor in the air, which is introduced into the interior of the device by a special method; the electrochromic layer capable of independently regulating visible light and near-infrared light transmittance is an amorphous single-component electrochromic material with abundant oxygen defects, which has three working modes.

Description

Technical Field

[0001] The invention relates to a full-thin film electrochromic device and a preparation method thereof. Background Art

[0002] As environmental issues and energy crises become increasingly prominent, the need to reduce building energy consumption is more important than ever, and the design of electrochromic smart windows is one way to achieve this goal. Electrochromism refers to the stable and reversible change of optical properties (transmittance, reflectivity and absorptivity, etc.) caused by the redox reaction of materials under the action of an external electric field. Electrochromic devices assembled from electrochromic materials have broad application prospects in smart windows, displays, energy storage devices, spacecraft intelligent thermal control, and bionic camouflage. Considering that visible-near-infrared light (380-2500nm) carries more than 95% of the total irradiation energy from the sun to the earth, the realization of independent regulation of the transmittance of materials and devices in the visible-near-infrared band is of great significance for the development of the next generation of energy-saving electrochromic smart windows. This electrochromic smart window can independently change the input of visible light and solar radiation energy under the action of an external electric field, thereby significantly improving the indoor comfort of the building and saving energy in the lighting, heating, ventilation and air conditioning of the building. However, most electrochromic smart windows only have two modulation modes and cannot achieve independent regulation of visible light and near-infrared light. At present, electrochromic materials and devices for independent regulation of visible-near-infrared transmittance mainly focus on designing composite materials, one of which can regulate visible light through small polaron absorption, and the other material uses the localized surface plasmon resonance (LSPR) effect to regulate near-infrared infrared light. The preparation process of these composite materials is quite complicated, and usually requires the careful integration of two components with near-infrared modulation and near-infrared selection. It is difficult to achieve complete matching, and the cycle performance is poor and the regulation range is narrow, which limits its application. Summary of the invention

[0003] The purpose of the present invention is to solve the problems in the prior art that all-thin-film electrochromic devices are difficult to independently regulate the transmittance of visible light and near-infrared light, have weak regulation capabilities and poor cyclic stability, and have only two regulation modes, and to provide an all-thin-film electrochromic device that can independently regulate the transmittance of visible light and near-infrared light and a method for preparing the same.

[0004] A fully thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance, comprising a transparent bottom electrode, an ion storage layer, an ion conduction layer, an electrochromic layer capable of independently regulating visible light and near-infrared light transmittance, and a transparent top electrode, wherein the electrolyte is water or water vapor in the air, which is introduced into the device by a special method;

[0005] The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is an amorphous single-component electrochromic material with abundant oxygen defects.

[0006] A method for preparing a thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance is specifically completed in the following steps:

[0007] 1. Prepare a transparent bottom electrode on a substrate by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation;

[0008] 2. preparing an ion storage layer on the transparent bottom electrode by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation;

[0009] 3. preparing an ion conducting layer on the ion storage layer by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation;

[0010] Fourth, an electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is prepared on the ion-conducting layer by electron beam evaporation;

[0011] The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is an amorphous single-component electrochromic material with abundant oxygen defects and a thickness of 400 nm;

[0012] 5. A transparent top electrode is prepared on the electrochromic layer that can independently adjust the transmittance of visible light and near-infrared light by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation to obtain a five-layer thin film structure electrochromic device;

[0013] 6. Immerse the five-layer thin-film structure electrochromic device in water or place it in the air. Water penetrates into the ion conduction layer of the device through the surface or edge of the device, obtaining a full-thin-film electrochromic device that can independently adjust the transmittance of visible light and near-infrared light.

[0014] Principle of the present invention:

[0015] 1. The present invention adopts a physical vapor deposition method to prepare a single-component electrochromic layer that can independently adjust the transmittance of visible light and near-infrared light. By controlling the surface morphology and internal oxygen vacancy concentration of the single-component electrochromic layer, the single-component electrochromic material can not only adjust visible light through small polaron absorption, but also use localized surface plasmon resonance effect to adjust near-infrared light, thereby realizing independent regulation of visible light and near-infrared light transmittance; on this basis, a five-layer all-thin-film electrochromic device with independent regulation of visible light and near-infrared light is designed, including a transparent bottom electrode, an ion storage layer, an ion conduction layer, and an independently regulatable An electrochromic layer and a transparent top electrode with high visible light and near-infrared light transmittance, wherein the electrolyte is water in the air environment, and the introduced water mainly penetrates into the ion conduction layer of the device through the surface or edge of the device; under the action of high voltage, the water inside the device will ionize protons, and the protons will be transferred from the ion conduction layer through proton hopping (Grotthus mechanism) and adsorbed on the surface of the electrochromic layer, and the near-infrared infrared light transmittance will be regulated by the LSPR effect; under the action of low voltage, the protons will be embedded in the interior of the electrochromic layer, and the visible light transmittance will be adjusted by small polaron absorption, thereby achieving the purpose of selective regulation of light (visible light) and heat (near-infrared light).

[0016] Effects of the present invention:

[0017] 1. In the all-thin film electrochromic device capable of independently regulating visible light and near-infrared light transmittance, under the action of high voltage, protons are transferred from the ion conduction layer through proton hopping (Grotthus mechanism) and adsorbed on the surface of the electrochromic layer, thereby regulating the near-infrared light transmittance through the LSPR effect; under the action of low voltage, protons will be embedded in the interior of the electrochromic layer, and the visible light transmittance will be adjusted through the absorption of small polarons, thereby achieving the purpose of selectively regulating light (visible light) and heat (near-infrared light); the all-thin film electrochromic device capable of independently regulating visible light and near-infrared light transmittance prepared by the present invention The film electrochromic device has a bright mode (high transmittance of both visible light and near-infrared, suitable for building lighting and winter building heating), a cold mode (blocking most of the near-infrared light while keeping visible light transmittance, suitable for building lighting and reducing the solar heat gain of buildings) and a dark mode (neither visible light nor near-infrared is transmittance, further reducing the solar heat gain of buildings and protecting personal privacy). In addition, the transmittance regulation range is large, the cycle stability is good, and the energy-saving effect is obvious (the indoor temperature can be adjusted by regulating the solar heat entering the building, reducing the use of air conditioning), which can better meet the actual needs of smart windows.

[0018] 2. The all-thin-film electrochromic device with independently adjustable visible light and near-infrared light transmittance prepared by the present invention has three working modes: bright mode (visible light transmittance is greater than 80%, near-infrared transmittance is greater than 75%, suitable for building lighting and winter building heating), cold mode (visible light transmittance is greater than 50%, which can block more than 60% of near-infrared solar heat, suitable for building lighting and reducing building solar heat gain) and dark mode (visible light and near-infrared light transmittance are both less than 10%, blocking more than 90% of solar heat, further reducing building solar heat gain and protecting personal privacy); the transmittance of the device in the visible region varies by 60-90%, the transmittance in the near-infrared region varies by 55-85%, the coloring time is 1-5s, the fading time is 3-8s, and the coloring efficiency is 50-200cm 2 / C, and has good cycle stability, and can stably cycle more than 2000 times; at the same time, the smart window based on the electrochromic device can significantly adjust the indoor temperature of the model room by regulating the solar heat entering the building, and can achieve a temperature control range of 10 to 30°C, which can better meet the actual needs of smart windows. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 1 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light with different oxygen vacancy concentrations, wherein 1 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when no oxygen is introduced in step 4 of Example 2, 2 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 1 is 2.5 sccm, 3 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 3 is 5 sccm, 4 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 4 is 7.5 sccm, and 5 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 5 is 10 sccm;

[0020] Figure 2 This is a SEM image of the all-thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance prepared in Example 1;

[0021] Figure 3 The transmittance change spectra of ultraviolet-visible light and near-infrared light of the all-thin-film electrochromic device capable of independently adjusting the transmittance of visible light and near-infrared light prepared in Example 1 in different modes;

[0022] Figure 4It is a solar radiation spectrum diagram of the all-thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance prepared in Example 1 under different modes. DETAILED DESCRIPTION

[0023] Specific implementation method 1: In this implementation method, a fully thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance comprises a transparent bottom electrode, an ion storage layer, an ion conduction layer, an electrochromic layer capable of independently regulating visible light and near-infrared light transmittance, and a transparent top electrode, wherein the electrolyte is water or water vapor in the air, which is introduced into the device by a special method;

[0024] The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is an amorphous single-component electrochromic material with abundant oxygen defects.

[0025] Specific implementation method 2: This implementation method is different from specific implementation method 1 in that: the all-thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance has three working modes: the first working mode is a bright mode, the second working mode is a cold mode, and the third working mode is a dark mode; the device can independently regulate visible light and near-infrared light transmittance, and has good cycle stability, and can stably cycle for more than 20,000 cycles; the smart window prepared based on the device can significantly regulate the indoor temperature of the model room, and can achieve a temperature regulation range of 16.7°C, with obvious energy-saving effect. The other steps are the same as those in specific implementation method 1.

[0026] Specific implementation method three: The difference between this implementation method and specific implementation method one or two is that: the transparent bottom electrode and the transparent top electrode are connected to the positive and negative electrodes of the DC voltage source respectively. At +3.0V or 0V, the fully thin-film electrochromic device that independently regulates the transmittance of visible light and near-infrared light is in bright mode, and is highly transparent in both the visible light and near-infrared light regions; at a higher voltage of 0V to -1.5V, the fully thin-film electrochromic device that independently regulates the transmittance of visible light and near-infrared light enters a cold mode, blocking most of the near-infrared light while maintaining visible light transmission; at -1.5V to -3.0V, the fully thin-film electrochromic device that independently regulates the transmittance of visible light and near-infrared light enters a dark mode, and neither visible light nor near-infrared light is transmitted. The other steps are the same as specific implementation method one or two.

[0027] Specific embodiment 4: This embodiment differs from specific embodiments 1 to 3 in that: the electrochromic layer capable of independently adjusting visible light and near-infrared light transmittance is oxygen-defect doped titanium oxide, oxygen-defect doped amorphous tungsten oxide or oxygen-defect doped niobium oxide; the thickness of the electrochromic layer is 100 to 1000 nm. The other steps are the same as those of specific embodiments 1 to 3.

[0028] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that the surface morphology and internal oxygen vacancy concentration of the electrochromic layer capable of independently adjusting visible light and near-infrared light transmittance are adjusted by controlling the evaporation rate of the material and the mass flow rate of oxygen during the electron beam evaporation process; the evaporation rate of the material during the electron beam evaporation process is The mass flow rate of oxygen is 0-20 sccm. The other steps are the same as those in the first to fourth embodiments.

[0029] Specific embodiment 6: This embodiment differs from specific embodiments 1 to 5 in that: a method for preparing a full-thin film electrochromic device capable of independently regulating visible light and near-infrared light transmittance is specifically completed in the following steps:

[0030] 1. Prepare a transparent bottom electrode on a substrate by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation;

[0031] 2. preparing an ion storage layer on the transparent bottom electrode by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation;

[0032] 3. preparing an ion conducting layer on the ion storage layer by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation;

[0033] Fourth, an electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is prepared on the ion-conducting layer by electron beam evaporation;

[0034] The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is an amorphous single-component electrochromic material with abundant oxygen defects and a thickness of 400 nm;

[0035] 5. A transparent top electrode is prepared on the electrochromic layer that can independently adjust the transmittance of visible light and near-infrared light by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation to obtain a five-layer thin film structure electrochromic device;

[0036] 6. Immerse the five-layer thin film structure electrochromic device in water or put it in the air, and water penetrates into the ion conduction layer of the device through the surface or edge of the device to obtain a full-thin film electrochromic device that can independently adjust the transmittance of visible light and near-infrared light. The other steps are the same as those in specific embodiments 1 to 5.

[0037] Specific embodiment 7: This embodiment differs from specific embodiments 1 to 6 in that: the substrate described in step 1 is a rigid substrate or a flexible substrate; the rigid substrate is quartz glass or a polycarbonate plate; the flexible substrate is polyethylene terephthalate, polydimethylsiloxane or polyimide. The other steps are the same as those of specific embodiments 1 to 6.

[0038] Specific embodiment eight: This embodiment differs from specific embodiments one to seven in that: the transparent bottom electrode and transparent top electrode are one or a combination of indium tin oxide, fluorine-doped tin oxide, aluminum-doped zinc oxide, conductive polymer, carbon nanotube, graphene, metal nanowire and metal grid, with a thickness of 10 to 600 nm; the ion conduction layer is one of tantalum oxide, magnesium fluoride, zirconium oxide, silicon oxide and silicon nitride, with a thickness of 10 to 1000 nm; the ion storage layer is nickel oxide, iridium oxide or molybdenum oxide, with a thickness of 10 to 800 nm. The other steps are the same as those of specific embodiments one to seven.

[0039] Specific embodiment 9: This embodiment differs from specific embodiments 1 to 8 in that: the method for preparing an electrochromic layer capable of independently regulating visible light and near-infrared light transmittance on an ion conducting layer by electron beam evaporation in step 4 is as follows:

[0040] The transparent glass substrate containing the ion conducting layer was fixed on the sample plate and placed in the evaporation chamber. The distance between the tungsten oxide evaporation material and the substrate was kept at about 30 cm, and the vacuum was evacuated to 3×10 -3 Pa, and then open the mass flow controller to introduce oxygen into the vacuum chamber. The mass flow rate is controlled at 0-20 sccm, which is the evaporation rate from fast to slow, that is, 25, 20, 15, 10 and Each layer is plated at a thickness of about 100 nm at a certain evaporation rate; at the same time, the substrate is rotated at a speed of 20 revolutions per minute during the evaporation coating process to ensure the uniformity of the film layer; thus, by controlling the mass flow rate of oxygen in the electron beam evaporation process from 0 to 20 sccm and the evaporation rate, the oxygen vacancy concentration and surface morphology in the tungsten oxide can be precisely controlled. The other steps are the same as those in the first to eighth embodiments.

[0041] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that: in step 6, the five-layer thin film structure electrochromic device is immersed in water for 1 hour to 48 hours; the five-layer thin film structure electrochromic device is placed in the air for 1 hour to 72 hours; the five-layer thin film structure electrochromic device is placed in a closed box with constant temperature and humidity for 1 hour to 72 hours, and the temperature of the closed box with constant temperature and humidity is 10°C to 35°C, and the humidity is 50% to 100%. The other steps are the same as specific embodiments 1 to 9.

[0042] The following examples are used to verify the beneficial effects of the present invention:

[0043] Example 1: A method for preparing a thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance is specifically completed by the following steps:

[0044] 1. A transparent bottom electrode is prepared on a transparent glass substrate by magnetron sputtering. The transparent bottom electrode is indium tin oxide and has a thickness of 270 nm.

[0045] The transparent glass substrate described in step 1 is quartz glass;

[0046] 2. An ion storage layer is prepared on the transparent bottom electrode by electron beam evaporation. The ion storage layer is nickel oxide and has a thickness of 150 nm.

[0047] 3. An ion conducting layer is prepared on the ion storage layer by electron beam evaporation. The ion conducting layer is zirconium oxide and has a thickness of 325 nm.

[0048] 4. An electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is prepared on the ion-conducting layer by electron beam evaporation. The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is tungsten oxide modified with oxygen vacancies, and has a thickness of 400 nm. The surface morphology and internal oxygen vacancy content of tungsten oxide are regulated by controlling the material deposition rate and oxygen flow rate during electron beam evaporation. The specific preparation method is as follows: a transparent glass substrate containing an ion-conducting layer is fixed on a sample plate, placed in an evaporation chamber, the distance between the tungsten oxide evaporation material and the substrate is kept at about 30 cm, and the evaporation chamber is evaporated to 3×10 -3 Pa, and then open the mass flow controller to introduce oxygen into the vacuum chamber, the mass flow rate is controlled at 2.5sccm, in order to make the surface of the single-component electrochromic layer loose without affecting the bonding force with the substrate, the evaporation rate is changed by adjusting the size of the electron beam current during the evaporation process, the rate changes from fast to slow, that is, 25, 20, 15, 10 and Each layer is plated at about 100nm at the evaporation rate; at the same time, the substrate is rotated at a speed of 20 revolutions per minute during the evaporation coating process to ensure the uniformity of the film layer; by controlling the mass flow rate of oxygen 2.5sccm and the evaporation rate during the electron beam evaporation process, the oxygen vacancy concentration and surface morphology in tungsten oxide can be precisely controlled;

[0049] 5. A top transparent conductive layer is prepared on the electrochromic layer by magnetron sputtering, wherein the transparent top electrode is indium tin oxide and the thickness of the transparent top conductive layer is 75 nm, thereby obtaining a five-layer thin film structure electrochromic device;

[0050] 6. Place the five-layer thin-film structure electrochromic device in a closed box with constant temperature and humidity. The temperature in the box is 25°C and the humidity in the box is 50-60%. The placement time is 48 hours to obtain a full-thin film electrochromic device that can independently adjust the transmittance of visible light and near-infrared light.

[0051] Example 2: The difference between this example and Example 1 is that in step 4, the mass flow controller is turned on to introduce oxygen into the vacuum chamber, and the mass flow rate is controlled at 0 sccm. The other steps and parameters are the same as those in Example 1.

[0052] Example 3: The difference between this example and Example 1 is that in step 4, the mass flow controller is turned on to introduce oxygen into the vacuum chamber, and the mass flow rate is controlled at 5 sccm. The other steps and parameters are the same as those in Example 1.

[0053] Example 4: The difference between this example and Example 1 is that in step 4, the mass flow controller is turned on to introduce oxygen into the vacuum chamber, and the mass flow rate is controlled at 7.5 sccm. The other steps and parameters are the same as those in Example 1.

[0054] Example 5: The difference between this example and Example 1 is that in step 4, the mass flow controller is turned on to introduce oxygen into the vacuum chamber, and the mass flow rate is controlled at 10 sccm. The other steps and parameters are the same as those in Example 1.

[0055] Figure 1 1 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light with different oxygen vacancy concentrations, wherein 1 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when no oxygen is introduced in step 4 of Example 2, 2 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 1 is 2.5 sccm, 3 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 3 is 5 sccm, 4 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 4 is 7.5 sccm, and 5 is an EPR spectrum of the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light prepared when the mass flow rate of oxygen introduced in step 4 of Example 5 is 10 sccm;

[0056] from Figure 1 It can be seen that the g values ​​of the tungsten oxide films obtained in the five examples are all 2.0038 (g = 2.003 ± 0.001 can be attributed to the oxygen vacancies on the surface of the tungsten oxide, which is direct evidence of the presence of oxygen vacancies on the surface of the tungsten oxide film), which proves that there are a large number of oxygen vacancies in the tungsten oxide sample. As the oxygen flow rate increases, the intensity of the EPR peak gradually weakens, indicating that as the oxygen flow rate increases during preparation, the oxygen vacancies inside the tungsten oxide film decrease. These results show that in a low-oxygen environment, oxygen vacancies are successfully introduced into tungsten oxide through the electron beam evaporation strategy, and the concentration of oxygen vacancies can be accurately controlled by the mass flow rate of oxygen during the evaporation process.

[0057] Figure 2 This is a SEM image of the all-thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance prepared in Example 1;

[0058] from Figure 2 It can be seen that the interfaces between the layers in the all-thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance prepared in Example 1 are clear and crack-free, which means that all the films have good physical and chemical stability.

[0059] Figure 3 The transmittance change spectra of ultraviolet-visible light and near-infrared light of the all-thin-film electrochromic device capable of independently adjusting the transmittance of visible light and near-infrared light prepared in Example 1 in different modes;

[0060] Figure 4 It is a solar radiation spectrum diagram of the all-thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance prepared in Example 1 under different modes;

[0061] from Figure 3 and Figure 4 It can be seen that the all-thin film electrochromic device can independently adjust the transmittance of visible light and near-infrared light, and has three working modes: ① Bright mode (+3.0~0V): 81.0% transmittance of visible light (380~780 nanometers), 64.0% transmittance of near-infrared light (780~2500 nanometers); ② Cold mode (0~-1.5V): 57.6% transmittance of visible light, and 68.6% of near-infrared heat can be blocked; ③ Dark mode (-1.5~-3.0V): 4.5% transmittance of visible light, 4.0% transmittance of near-infrared light, and 96.3% of near-infrared heat can be blocked; the transmittance of the device in the visible region changes by 76.5%, the transmittance in the near-infrared region changes by 60.0%, the coloring time is 2.5s, the fading time is 3.5s, and the coloring efficiency is 106.89cm 2 / C and has good cycle stability, which can stably cycle for more than 8000 cycles. At the same time, the smart window based on the electrochromic device can significantly adjust the indoor temperature of the model room, and can achieve a temperature control range of 14.8℃.

Claims

1. A thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance, characterized in that The electrochromic device comprises a transparent bottom electrode, an ion storage layer, an ion conduction layer, an electrochromic layer capable of independently regulating visible light and near-infrared light transmittance, and a transparent top electrode, wherein the electrolyte is water, and the water penetrates into the ion conduction layer of the device through the surface or edge of the device; The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is an amorphous single-component electrochromic material with abundant oxygen defects.

2. The all-thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance according to claim 1, characterized in that The transparent bottom electrode and the transparent top electrode are respectively connected to the positive and negative electrodes of a DC voltage source. At +3.0V or 0V, the all-thin-film electrochromic device that independently regulates the transmittance of visible light and near-infrared light is in a bright mode, with high transmittance in both the visible light and near-infrared light regions; at 0V to -1.5V, the all-thin-film electrochromic device that independently regulates the transmittance of visible light and near-infrared light enters a cold mode, blocking most of the near-infrared light while maintaining visible light transmittance; at -1.5V to -3.0V, the all-thin-film electrochromic device that independently regulates the transmittance of visible light and near-infrared light enters a dark mode, with neither visible light nor near-infrared light being transmitted.

3. The all-thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance according to claim 1, characterized in that The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is oxygen-defect doped titanium oxide, oxygen-defect doped amorphous tungsten oxide or oxygen-defect doped niobium oxide; the thickness of the electrochromic layer is 100-1000nm.

4. A thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance according to any one of claims 1 to 2, characterized in that The surface morphology and internal oxygen vacancy concentration of the electrochromic layer capable of independently regulating visible light and near-infrared light transmittance are regulated by controlling the evaporation rate of the material and the mass flow rate of oxygen during electron beam evaporation; the evaporation rate of the material during electron beam evaporation is The mass flow rate of oxygen was 0-20 sccm.

5. A method for preparing a thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance as claimed in claim 1, characterized in that The preparation method is specifically completed according to the following steps:

1. Prepare a transparent bottom electrode on a substrate by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation; 2. preparing an ion storage layer on the transparent bottom electrode by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation; 3. preparing an ion conducting layer on the ion storage layer by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation; Fourth, an electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is prepared on the ion-conducting layer by electron beam evaporation; The electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light is an amorphous single-component electrochromic material with abundant oxygen defects and a thickness of 400 nm; 5. A transparent top electrode is prepared on the electrochromic layer that can independently adjust the transmittance of visible light and near-infrared light by vacuum coating, magnetron sputtering, vacuum thermal evaporation or electron beam evaporation to obtain a five-layer thin film structure electrochromic device; 6. Immerse the five-layer thin-film structure electrochromic device in water, place it in a closed box with constant temperature and humidity, or place it in the air. Water penetrates into the ion conduction layer of the device through the surface or edge of the device, obtaining a full-thin-film electrochromic device that can independently adjust the transmittance of visible light and near-infrared light.

6. The method for preparing a thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance according to claim 5, characterized in that The substrate described in step 1 is a rigid substrate or a flexible substrate; the rigid substrate is quartz glass or a polycarbonate plate; the flexible substrate is polyethylene terephthalate, polydimethylsiloxane or polyimide.

7. The method for preparing a thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance according to claim 5, characterized in that The transparent bottom electrode and the transparent top electrode are one or a combination of indium tin oxide, fluorine-doped tin oxide, aluminum-doped zinc oxide, conductive polymers, carbon nanotubes, graphene, metal nanowires and metal grids, with a thickness of 10 to 600 nm; the ion conduction layer is one of tantalum oxide, magnesium fluoride, zirconium oxide, silicon oxide and silicon nitride, with a thickness of 10 to 1000 nm; the ion storage layer is nickel oxide, iridium oxide or molybdenum oxide, with a thickness of 10 to 800 nm.

8. The method for preparing a thin-film electrochromic device capable of independently regulating visible light and near-infrared light transmittance according to claim 5, characterized in that The method for preparing the electrochromic layer capable of independently regulating the transmittance of visible light and near-infrared light on the ion conducting layer by electron beam evaporation in step 4 is as follows: The transparent glass substrate containing the ion conducting layer was fixed on the sample plate and placed in the evaporation chamber. The tungsten oxide evaporation material was kept 30 cm away from the substrate and the vacuum was drawn to 3×10 -3 Pa, and then open the mass flow controller to introduce oxygen into the vacuum chamber. The mass flow rate is controlled at 0-20 sccm, which is the evaporation rate from fast to slow, that is, 25, 20, 15, 10 and 100nm is plated at each evaporation rate; at the same time, the substrate is kept rotating at a speed of 20 revolutions per minute during the evaporation coating process to ensure the uniformity of the film layer; thus, by controlling the mass flow rate of oxygen in the electron beam evaporation process from 0 to 20sccm and the evaporation rate, the oxygen vacancy concentration and surface morphology in tungsten oxide can be accurately controlled.

9. The method for preparing a thin-film electrochromic device capable of independently adjusting visible light and near-infrared light transmittance according to claim 5, characterized in that In step six, the five-layer thin film structure electrochromic device is immersed in water for 1 hour to 48 hours; the five-layer thin film structure electrochromic device is placed in the air for 1 hour to 72 hours; the five-layer thin film structure electrochromic device is placed in a closed box with constant temperature and humidity for 1 hour to 72 hours, and the temperature of the closed box with constant temperature and humidity is 10°C to 35°C, and the humidity is 50% to 100%.

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