阅读说明：本技术 基于多层功能薄膜的电致变色器件及其制备方法 (Electrochromic device based on multilayer functional thin film and preparation method thereof ) 是由 杨恢东 彭斯冉 邵海平 张婧妍 夏锦辉 宋香荣 于 2019-10-16 设计创作，主要内容包括：本发明为基于多层功能薄膜的电致变色器件及其制备方法,其器件包括依次连接的第一透明电极层、多个阴极变色功能层、电解质层、阳极变色功能层和第二透明电极层,第一透明电极层设置在阴极变色功能层的相对外表面上,第二透明电极层设置在阳极变色功能层的相对外表面上；多个阴极变色功能层包括由MoO<Sub>3</Sub>材料制成的主阴极变色功能层和被覆于主阴极变色功能层的相对外表面的辅阴极变色功能层,主阴极变色功能层厚度大于辅阴极变色功能层厚度。本发明融合了多个变色功能层材料的优点,以解决钼的氧化物的电致变色器件的附着性差、稳定性不佳的问题,实现所制器件的稳定性、电致变色响应速度和光调范围等综合性能的提升,降低器件制作成本。(The invention relates to an electrochromic device based on a multilayer functional film and a preparation method thereof, wherein the device comprises a first transparent electrode layer, a plurality of cathode color-changing functional layers, an electrolyte layer, an anode color-changing functional layer and a second transparent electrode layer which are sequentially connected, wherein the first transparent electrode layer is arranged on the opposite outer surface of the cathode color-changing functional layer, and the second transparent electrode layer is arranged on the opposite outer surface of the anode color-changing functional layer; the plurality of cathodic discoloration functional layers comprise MoO 3 MaterialThe color-changing functional layer comprises a main cathode color-changing functional layer and an auxiliary cathode color-changing functional layer coated on the outer surface of the main cathode color-changing functional layer, wherein the thickness of the main cathode color-changing functional layer is larger than that of the auxiliary cathode color-changing functional layer. The invention integrates the advantages of a plurality of color-changing functional layer materials, solves the problems of poor adhesion and poor stability of the electrochromic device of molybdenum oxide, improves the comprehensive properties of the manufactured device such as stability, electrochromic response speed, light modulation range and the like, and reduces the manufacturing cost of the device.)

1. The electrochromic device based on the multilayer functional film is characterized by comprising a first transparent electrode layer, a plurality of cathode color-changing functional layers, an electrolyte layer, an anode color-changing functional layer and a second transparent electrode layer which are sequentially connected, wherein the first transparent electrode layer is arranged on the outer surface opposite to the cathode color-changing functional layer, and the second transparent electrode layer is arranged on the outer surface opposite to the anode color-changing functional layer;

the plurality of cathodic discoloration functional layers comprise MoO₃The color-changing functional layer comprises a main cathode color-changing functional layer made of the material and an auxiliary cathode color-changing functional layer coated on the opposite outer surface of the main cathode color-changing functional layer, wherein the thickness of the main cathode color-changing functional layer is larger than that of the auxiliary cathode color-changing functional layer.

2. The electrochromic device based on multi-layered functional thin film according to claim 1, wherein the thickness of the primary cathode color-changing functional layer is several times as thick as that of the secondary cathode color-changing functional layer, and the secondary cathode color-changing functional layer is formed by WO₃And TiO₂The material is made by layering.

3. The electrochromic device according to claim 1, wherein the first transparent electrode layer and the second transparent electrode layer are made of indium tin oxide material and have an area resistance of 10-50 Ω -cm²And the thickness is 150-200 nm.

4. The electrochromic device based on multi-layer functional film according to claim 1, wherein the auxiliary cathode color-changing functional layer comprises a first cathode color-changing functional layer, the first cathode color-changing functional layer is coated on the first transparent electrode layer, and the main cathode color-changing functional layer is a second cathode color-changing functional layer and is coated on the first cathode color-changing functional layer.

5. The electrochromic device based on multi-layer functional thin film as claimed in claim 4Element, characterized in that said first cathodic discolouring functional layer is WO₃A layer having a thickness of between 50-150 nm; the thickness of the second cathode color-changing functional layer is between 250-600 nm.

6. The multilayer functional film-based electrochromic device according to claim 4, wherein the secondary cathodic discoloration functional layer further comprises a third cathodic discoloration functional layer disposed between the primary cathodic discoloration functional layer and the electrolyte layer.

7. The electrochromic device based on multi-layered functional film according to claim 6, wherein the third functional layer for cathode color change is WO₃A layer with a thickness of between 50 and 120 nm.

8. The electrochromic device according to claim 4 or 6, further comprising a substrate layer, wherein the first transparent electrode layer is disposed on the substrate layer.

9. The method for preparing an electrochromic device based on a multi-layered functional thin film according to claim 8, comprising the steps of:

cutting a substrate layer into a proper size, removing dirt and scale, cleaning in an ultrasonic cleaning machine, washing with deionized water, drying with industrial nitrogen, placing into a magnetron sputtering chamber, and vacuumizing the magnetron sputtering chamber;

the first transparent electrode layer and the second transparent electrode layer are sputtered by taking indium tin oxide as a target under the argon environment and are respectively coated on the substrate layer and the anode discoloration function layer;

the first cathode discoloration functional layer is pure tungsten as a target material, the gas flow of oxygen and argon is adjusted, sputtering is carried out at normal temperature, and tungsten ions and oxygen ions are combined to form WO₃Is covered on the first transparent electrode layer;

the second cathode color-changing functional layer takes pure molybdenum as a target material, adjusts the gas flow of oxygen and argon, and performs normal-temperature sputtering to obtain molybdenum ionsCombined with oxygen ions to form MoO₃Is covered on the first cathode color-changing functional layer;

the electrolyte layer takes lithium tantalate as a target material, regulates the gas flow of argon in an argon environment, sputters at normal temperature, and is coated on the second cathode discoloration functional layer;

the anode discoloration functional layer takes nickel as a target material, adjusts the gas flow of oxygen and argon, performs sputtering at normal temperature, and combines nickel ions and oxygen ions to form NiOx to be coated on the electrolyte layer.

10. The method of claim 9, wherein the secondary cathodic discoloration functional layer further comprises a third cathodic discoloration functional layer disposed between the primary cathodic discoloration functional layer and the electrolyte layer;

the preparation method further comprises the following steps: preparing a third cathode color-changing functional layer, taking pure tungsten as a target, adjusting the gas flow of oxygen and argon, and sputtering at normal temperature to form WO₃Is coated on the second cathode color-changing functional layer.

Technical Field

The invention relates to an electrochromic device technology, in particular to an electrochromic device based on a multilayer functional film and a preparation method thereof.

Background

Electrochromism is a phenomenon that the optical properties (reflectivity, transmittance, absorptivity and the like) of a material generate stable and reversible color change under the action of an external electric field, and the electrochromism is represented as reversible change of color and transparency in appearance. Materials having electrochromic properties are referred to as electrochromic materials, and devices made with electrochromic materials are referred to as electrochromic devices.

The electrochromic device has adjustability of light absorption and transmission under the action of an electric field, can selectively absorb or reflect external heat radiation and internal heat diffusion, and reduces a large amount of energy which is consumed for keeping office buildings and civil houses cool in summer and warm in winter; meanwhile, the purposes of improving the natural illumination degree and preventing peeping are achieved; the problem of urban light pollution which is continuously worsened in modern times is solved, and the method is a development direction of energy-saving building materials. Electrochromic devices have attracted attention in areas such as windows, rear view mirrors, and display screens. Meanwhile, all-solid-state electrochromic devices also have some problems, such as higher cost, unsatisfactory stability of the devices, and the like, and at present, deep research on all-solid-state electrochromic devices is still needed to help the performance improvement and industrialization realization of the electrochromic devices.

The complementary electrochromic device is an electrochromic device with better light modulation range and stability at present, and researchers have proposed the structure of 'electrode// anode color-changing functional layer// electrolyte layer// cathode color-changing functional layer// electrode'. The electrochromic functional layer is a core layer of the electrochromic device and is also a generation layer of a color change reaction. Tungsten oxide (WO)₃) The active layer is often used as a cathode discoloration active layer, and has relatively good stability, so that the active layer is widely researched by a plurality of researchers and has more mature report results. There is still room for improvement in the structure of "electrode// anode discoloration functional layer// electrolyte layer// cathode discoloration functional layer// electrode" described above.

In contrast, molybdenum (Mo) is a group-homologous metal element of tungsten (W), an oxide of molybdenum (MoO)₃) But the molybdenum oxide film has poor adhesion and poor stability when serving as an electrochromic functional layer, and shows that the film is easy to fall off, the electrochromic effect is obviously reduced after several times of electric field conversion, and few reports are made in academia on electrochromic devices based on molybdenum oxide. Corresponding to the disadvantages, the advantages of molybdenum oxide as an electrochromic functional layer are: 1) the lower driving voltage means that the electrochromic device of molybdenum oxide is more energy-saving and environment-friendly than the electrochromic device of tungsten oxide; 2) the global resource reserves of molybdenum are larger, about 1100 ten thousand tons, and tungsten is about 330 ten thousand tons, and the market price of molybdenum is lower than that of tungsten; 3) MoO₃Has a flatter absorption spectrum curve in the visible region, thus showing a better appearance than WO₃Softer neutral color, with better visual aesthetics. If the above MoO can be solved₃Based on MoO₃Electrochromic devices will either gain tremendous development. In addition, titanium oxide (TiO)₂) Etc. also have electrochromic effects.

From the above, the electrochromic device based on oxides of molybdenum, tungsten, etc. still has major disadvantages, and efforts are still needed to improve the overall electrochromic performance of the device.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides an electrochromic device based on a multilayer functional film, which adopts an electrochromic device structure with a plurality of color-changing functional layers and integrates the advantages of materials of the plurality of color-changing functional layers so as to solve the problems of poor adhesion and poor stability of an electrochromic device of molybdenum oxide, and improves the comprehensive performance of the electrochromic device such as the stability, electrochromic response speed, light modulation range and the like of the manufactured device and reduces the manufacturing cost of the device by integrating the advantages of a plurality of functional films.

The electrochromic device based on the multilayer functional film comprises a first transparent electrode layer, a plurality of cathode color-changing functional layers, an electrolyte layer, an anode color-changing functional layer and a second transparent electrode layer which are sequentially connected, wherein the first transparent electrode layer is arranged on the opposite outer surface of the cathode color-changing functional layer, and the second transparent electrode layer is arranged on the opposite outer surface of the anode color-changing functional layer;

the plurality of cathodic discoloration functional layers comprise MoO₃The color-changing functional layer comprises a main cathode color-changing functional layer made of the material and an auxiliary cathode color-changing functional layer coated on the opposite outer surface of the main cathode color-changing functional layer, wherein the thickness of the main cathode color-changing functional layer is larger than that of the auxiliary cathode color-changing functional layer.

Preferably, the thickness of the primary cathode color-changing functional layer is several times of that of the secondary cathode color-changing functional layer, and the secondary cathode color-changing functional layer can be formed by WO₃And TiO₂Etc. are made from one or more of the materials in layers.

Preferably, the auxiliary cathode color-changing functional layer comprises a first cathode color-changing functional layer, the first cathode color-changing functional layer is covered on the first transparent electrode layer, and the main cathode color-changing functional layer is a second cathode color-changing functional layer and is covered on the first cathode color-changing functional layer.

Preferably, the secondary cathode discoloration functional layer further comprises a third cathode discoloration functional layer disposed between the primary cathode discoloration functional layer and the electrolyte layer.

The invention relates to a preparation method of an electrochromic device based on a multilayer functional film, which comprises the following steps:

cutting a substrate layer into a proper size, removing dirt and scale, cleaning in an ultrasonic cleaning machine, washing with deionized water, drying with industrial nitrogen, placing into a magnetron sputtering chamber, and vacuumizing the magnetron sputtering chamber;

the first transparent electrode layer and the second transparent electrode layer are sputtered by taking indium tin oxide as a target under the argon environment and are respectively coated on the substrate layer and the anode discoloration function layer;

the first cathode discoloration functional layer is pure tungsten as a target material, the gas flow of oxygen and argon is adjusted, sputtering is carried out at normal temperature, and tungsten ions and oxygen ions are combined to form WO₃Is covered on the first transparent electrode layer;

the second cathode color-changing functional layer takes pure molybdenum as a target material, adjusts the gas flow of oxygen and argon, performs sputtering at normal temperature, and combines molybdenum ions and oxygen ions to form MoO₃Is covered on the first cathode color-changing functional layer;

the electrolyte layer takes lithium tantalate as a target material, regulates the gas flow of argon in an argon environment, sputters at normal temperature, and is coated on the second cathode discoloration functional layer;

the anode discoloration functional layer takes nickel as a target material, adjusts the gas flow of oxygen and argon, performs sputtering at normal temperature, and combines nickel ions and oxygen ions to form NiOx to be coated on the electrolyte layer.

By means of the explanation of the technical scheme, compared with the prior art, the invention has the following beneficial effects:

1. the device of the invention is due to the thinner WO₃The oxide with better stability is used as other cathode discoloration functional layers to cover the thicker main cathode discoloration layer MoO₃To the opposite outer surface ofThe novel structure of the plurality of color-changing functional layers of the electrode/anode color-changing functional layer/electrolyte layer/plurality of cathode color-changing functional layers/electrode integrates the advantages of the materials of the plurality of color-changing functional layers, so that the MoO is combined on the premise of keeping better electrochromic performance (indexes such as optical modulation range, response time and the like) of the device₃Better isolate from the external water oxygen environment, namely play the role of similar buffer layer, improve the MoO₃The stability of the layer; and because W and Mo are VIB group elements, the oxides of the two elements can be combined well, and MoO₃The problem of poor adhesion is solved, the improvement of the comprehensive performance of devices such as stability, electrochromic response speed, light modulation range and the like is realized, and the manufacturing cost of the devices is reduced.

2. The device of the invention uses MoO₃The main electrochromic functional layer has a plurality of beneficial effects, and has more friendly visual perception of human eyes due to a flatter absorption spectrum curve; the driving voltage of the second device is more than that of WO₃The dominant electrochromic device is low, which means more energy saving and environmental protection; and thirdly, the using amount of W is greatly reduced, so that the cost of the whole device is reduced.

3. All structural film layers of the device are made of inorganic materials, so that the finished product has long service life, relatively low cost and high feasibility of industrialization.

Drawings

FIG. 1 is a schematic structural diagram of an electrochromic device based on a multi-layer functional thin film in example 1 of the present invention;

FIG. 2 is a schematic structural diagram of an electrochromic device based on a multi-layer functional thin film in example 2 of the present invention;

FIG. 3 is a graph showing the change of optical transmittance of a device manufactured in example 2 of the present invention during operation.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings, but embodiments of the invention are not limited thereto.

The electrochromic device comprises a first transparent electrode layer, a plurality of cathode color-changing functional layers, an electrolyte layer and an anode color-changing function which are sequentially connectedA layer and a second transparent electrode layer. The first transparent electrode layer is arranged on the opposite outer surface of the cathode color-changing functional layer, the second transparent electrode layer is arranged on the opposite outer surface of the anode color-changing functional layer, the first transparent electrode layer and the second transparent electrode layer are made of Indium Tin Oxide (ITO) materials, and the surface resistance is 10-50 omega-cm²And the thickness is 150-200 nm.

A plurality of cathode discoloration functional layers are made of MoO₃、WO₃And TiO₂The materials are combined in layers, wherein, MoO₃The number of other cathode color-changing functional layers (namely, auxiliary cathode color-changing functional layers) can be increased or reduced for the necessary main cathode color-changing functional layer, and one or more layers of other cathode color-changing functional layers are often coated on the main color-changing functional layer MoO₃An opposing outer surface of (a); a plurality of cathode color-changing functional layers are covered on the first transparent electrode layer; MoO contributing to the primary electrochromic Effect₃The layer thickness is thicker, between 150nm and 400nm, and is generally several times thicker than other film layers.

The electrolyte layer adopts tantalum oxide Ta₂O₅Lithium borate LiBO₂And lithium tantalate (LiTaO)₃One of the materials is coated on the second cathode color-changing functional layer, and the film thickness is 150-300 nm. The anode color-changing functional layer adopts nickel oxide NiOx and iridium oxide IrO₂Rhodium (Rh) oxide₂O₃One of these materials, preferably 100-150nm thick.

The following will explain the structure of the plurality of functional layers for cathodic discoloration by way of example.