CN105036564B - A kind of nanocrystalline enhancing tungsten oxide electrochomeric films and preparation method thereof - Google Patents

Abstract

It is using transparent conductive oxide (TCO) is nanocrystalline, amorphous tungsten oxide is prepared as matrix " nanocrystalline WO of TCO the invention discloses a kind of nanocrystalline enhancing tungsten oxide electrochomeric films₃Amorphous " two-phase laminated film；The invention also discloses the preparation method of the nanocrystalline enhancing tungsten oxide electrochomeric films.The present invention uses nanocrystalline enhancing technology, improve electrochromic property of the conventional oxidation W film in visible light wave range, utilize the nanocrystalline modulating characteristics near infrared band of TCO simultaneously, modulation of the tungsten oxide film near infrared band is realized, solves the problems, such as that tungsten oxide film cycle life falls short of in the prior art, the large scale materials Electrochromic speed of response is slow and lacks near-infrared modulation capability.

Description

A nanocrystalline enhanced tungsten oxide electrochromic film and its preparation method

technical field

The invention belongs to the technical field of inorganic functional materials, and in particular relates to a nanocrystal-reinforced tungsten oxide electrochromic film; the invention also relates to a preparation method of the nanocrystal-reinforced tungsten oxide electrochromic film.

Background technique

Tungsten oxide electrochromic film has great application value in the field of building energy-saving glass because of its real-time adjustment of indoor lighting and thermal insulation. It is considered to be the next-generation energy-saving window material to replace Low-e coated glass.

The tungsten oxide electrochromic glass window is mainly composed of transparent electrodes, tungsten oxide electrochromic film, lithium ion electrolyte, ion storage film, transparent electrode and other five layers, plus a low-voltage power supply to provide driving voltage to realize the electric However, the existing tungsten oxide-based electrochromic glass windows have the shortcomings of short cycle life, slow electrochromic response rate of large-sized glass, and lack of near-infrared modulation ability, which affects the wide use of this material in the field of energy-saving building glass. . The key material that affects the electrochromic performance of this window is tungsten oxide electrochromic thin film. Therefore, how to prepare tungsten oxide electrochromic with long cycle life of electrochromic materials, fast color change response rate of large-sized materials and near-infrared modulation ability Thin film is a problem that needs to be solved urgently.

Contents of the invention

The purpose of the present invention is to provide a nanocrystalline enhanced tungsten oxide electrochromic film to solve the problems of short cycle life of existing tungsten oxide-based electrochromic materials, slow discoloration response rate of large-sized materials and lack of near-infrared modulation ability.

Another object of the present invention is to provide a method for preparing the nanocrystal-reinforced tungsten oxide electrochromic film, and the preparation process is simple and convenient.

The technical solution adopted in the present invention is that a nanocrystalline enhanced tungsten oxide electrochromic film is prepared by embedding nanocrystalline transparent conductive oxide (TCO) into the substrate with amorphous tungsten oxide as the substrate. "TCO nanocrystalline-WO ₃ amorphous" dual-phase composite film.

The present invention is also characterized in that,

Nanocrystalline TCO is a heavily doped semiconductor, which is any one of tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO) or aluminum-doped zinc oxide (AZO).

The particle size of the nanocrystalline TCO is 5-20nm, and the carrier concentration is 10 ¹⁸ -10 ²¹ /cm ³ .

Another technical solution adopted in the present invention is a method for preparing a nanocrystalline enhanced tungsten oxide electrochromic film, the specific steps are as follows:

Step 1, after mixing tungsten chloride and TCO with metal nitrate, dissolve it in an organic solvent to obtain a mixed solution; add deionized water to it, stir at room temperature for 2 hours, and obtain a composite sol after fully dissolving;

Step 2, uniformly coating the composite sol obtained in step 1 on a transparent conductive oxide glass substrate by dipping or spin coating technology to form a gel film;

Step 3: Place the gel film obtained in Step 2 in an environment of 150°C for 10 minutes, then put it into a heat treatment furnace and keep it in an oxygen atmosphere at 200-300°C for 1 hour, then take it out, and air-cool it to room temperature to obtain the electro-induced Color changing film.

The present invention is also characterized in that,

In step 1, the metal nitrate used for TCO is a mixture of tin nitrate and indium nitrate; or a mixture of tin nitrate and antimony trichloride; or a mixture of zinc nitrate and aluminum nitrate.

In step 1, the molar ratio of tin nitrate, indium nitrate and tungsten chloride is 0.1:1:5-20; or the molar ratio of antimony trichloride, tin nitrate and tungsten chloride is 0.04:1:10-100; or The molar ratio of aluminum nitrate: zinc nitrate: tungsten chloride is 0.06:1:5-20.

In step 1, the organic solvent is one of methanol, ethanol and ethylene glycol methyl ether or a mixture of any several obtained in arbitrary proportions, and the molar concentration of tungsten chloride in the obtained mixed solution is 0.05-0.15 mol/L.

In step 1, the volume ratio of deionized water to organic solvent is 1:100.

The beneficial effect of the present invention is that the electrochromic performance of the traditional tungsten oxide film in the visible light band is improved by adopting the nanocrystal enhancement technology, and at the same time, the modulation characteristics of the TCO nanocrystal in the near-infrared band are used to realize the electrochromic performance of the tungsten oxide film in the near-infrared band. The modulation solves the problems in the prior art that the cycle life of the tungsten oxide thin film is not long enough, the electrochromic response rate of large-sized materials is slow, and the lack of near-infrared modulation ability.

Description of drawings

Fig. 1 is the transmittance curve of the colored state and the faded state of the "ITO nanocrystal _- WO3 amorphous" composite film obtained in Example ₁ and the "WO3 amorphous" film obtained in the comparative example;

Fig. 2 is the electrochromic response time of the "ITO nanocrystalline-WO ₃ amorphous" composite film obtained in Example 1 and the "WO ₃ amorphous" film obtained in the comparative example.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1

Preparation of "ITO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 0.9914g of tungsten chloride, 0.0477g of indium nitrate, and 0.0046g of tin nitrate, dissolve them in 49.5mL of methanol, add 0.5mL of deionized water to it, and stir at room temperature for 2 hours to fully dissolve, and then obtain tungsten, indium, The composite sol of tin; the obtained composite sol is uniformly coated on the transparent conductive oxide glass substrate by dipping or spin-coating technology to form a gel film, dried at 150°C for 10 minutes, and then placed in a heat treatment furnace 200-300°C in an oxygen atmosphere for 1 hour, then take it out, and air-cool to room temperature to obtain the "ITO nanocrystal-WO ₃ amorphous" dual-phase composite film.

The transmittance curves of the colored state and the faded state of the film obtained in this embodiment are shown in Figure 1, the optical modulation contrast ΔT% in the visible light band is 70%; the optical modulation contrast ΔT% at the 1200nm wavelength band is 50%; 100×100mm ² film color change response time 1s, the electrochromic response time chart of the film obtained in this example is shown in Figure 2; after 2000 coloring and fading treatments, the charge storage capacity of the film decreased only by 3%.

Example 2

Preparation of "ITO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 3g of tungsten chloride, 0.5777g of indium nitrate, and 0.055g of tin nitrate, dissolve them in 49.5mL of ethanol, add 0.5mL of deionized water to it, and stir at room temperature for 2 hours to dissolve fully, and then get tungsten, indium, and tin The composite sol of the composite sol; the obtained composite sol is evenly coated on the transparent conductive oxide glass substrate by dipping or spin-coating technology to form a gel film. It was kept in an oxygen atmosphere at ~300°C for 1 hour, then it was taken out, and air-cooled to room temperature to obtain an "ITO nanocrystalline-WO ₃ amorphous" dual-phase composite film.

The film obtained in this example has an optical modulation contrast ΔT% in the visible light band of 65%; an optical modulation contrast ΔT% in the 1200nm wavelength band is 53% ^; the color change response time of the 100×100mm film is 1s, after 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 2%.

Example 3

Preparation of "ITO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 2g of tungsten chloride, 0.1527g of indium nitrate, and 0.0147g of tin nitrate, and dissolve them in 49.5mL of ethylene glycol methyl ether, add 0.5mL of deionized water to it, and stir at room temperature for 2 hours to fully dissolve to obtain tungsten-containing , indium, and tin composite sol; the resulting composite sol is uniformly coated on a transparent conductive oxide glass substrate by dipping or spin coating technology to form a gel film, dried at 150°C for 10 minutes, and then placed in a heat treatment The furnace was kept in an oxygen atmosphere at 200-300°C for 1 hour, then it was taken out, and air-cooled to room temperature to obtain a dual-phase composite film of "ITO nanocrystal-WO ₃ amorphous".

The film obtained in this example has an optical modulation contrast ΔT% in the visible light band of 72%, an optical modulation contrast ΔT% in the 1200nm wavelength band of 55%, and a 100× ^100mm2 film with a color change response time of 1 second. After 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 2%.

Example 4

Preparation of "ATO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 300g of tungsten chloride, 2.787g of tin nitrate, and 0.0693g of antimony trichloride, dissolve them in a mixed solution of 500mL of methanol and 513mL of ethanol, add 10mL of deionized water therein, and stir at room temperature for 2 hours after fully dissolving to obtain A composite sol containing tungsten, indium, and tin; using dipping or spin-coating techniques, the resulting composite sol is uniformly coated on a transparent conductive oxide glass substrate to form a gel film, dried at 150°C for 10 minutes, and placed Put it into a heat treatment furnace and keep it in an oxygen atmosphere at 200-300°C for 1h, then take it out, and cool it to room temperature in air to obtain the "ATO nanocrystalline-WO ₃ amorphous" dual-phase composite film.

The film obtained in this example has an optical modulation contrast ΔT% in the visible light band of 63%, an optical modulation contrast ΔT% in the 1200nm wavelength band of 50%, and a 100×100mm film with a color change response time of 1 ^second . After 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 4%.

Example 5

Preparation of "ATO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 10g of tungsten chloride, 0.929g of tin nitrate, and 0.0231g of antimony trichloride, dissolve them in a mixed solution of 400mL of methanol and 107mL of ethylene glycol methyl ether, add 5mL of deionized water to it, and stir at room temperature for 2 hours After fully dissolving, a composite sol containing tungsten, indium, and tin is obtained; the obtained composite sol is evenly coated on a transparent conductive oxide glass substrate by dipping or spin-coating technology to form a gel film. After drying for 10 minutes, put it into a heat treatment furnace and keep it in an oxygen atmosphere at 200-300°C for 1 hour, then take it out, and air-cool it to room temperature to obtain the "ATO nanocrystalline-WO ₃ amorphous" dual-phase composite film.

The film obtained in this example has an optical modulation contrast △T% in the visible light band of 65%, an optical modulation contrast ΔT% in the 1200nm band of 48%, and a 100×100mm film with a color change response time of 1 ^second . After 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 3%.

Example 6

Preparation of "ATO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 12g of tungsten chloride, 0.929g of tin nitrate, and 0.0231g of antimony trichloride, and dissolve them in a mixed solution of 150mL of methanol, 50mL of ethanol, and 53mL of ethylene glycol methyl ether, and add 2.5mL of deionized water to it, and at room temperature After stirring for 2 hours to fully dissolve, a composite sol containing tungsten, indium, and tin was obtained; the obtained composite sol was evenly coated on a transparent conductive oxide glass substrate by dipping or spin-coating techniques to form a gel film. After drying at ℃ for 10 minutes, put it into a heat treatment furnace and keep it in an oxygen atmosphere at 200-300 ℃ for 1 hour, then take it out, and air-cool to room temperature to obtain the "ATO nanocrystalline-WO ₃ amorphous" dual-phase composite film.

The film obtained in this example has an optical modulation contrast ΔT% in the visible light band of 70%, an optical modulation contrast ΔT% in the 1200nm wavelength band of 51%, and a 100×100mm film with a color change response time of 1 ^second . After 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 2%.

Example 7

Preparation of "AZO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 39.66g of tungsten chloride, 1.4875g of zinc nitrate, and 0.1125g of aluminum nitrate, dissolve them in 667mL of ethanol, add 6.7mL of deionized water to it, and stir at room temperature for 2 hours to fully dissolve, and then obtain a compound containing tungsten, indium, and tin. The composite sol of the composite sol; the obtained composite sol is evenly coated on the transparent conductive oxide glass substrate by dipping or spin-coating technology to form a gel film. It was kept in an oxygen atmosphere at ~300°C for 1 hour, then it was taken out, and air-cooled to room temperature to obtain an "AZO nanocrystalline-WO ₃ amorphous" dual-phase composite film.

The film obtained in this example has an optical modulation contrast ΔT% in the visible light band of 64%, an optical modulation contrast ΔT% in the 1200nm wavelength band of 45%, and a 100×100mm film with a color change response time of 1 ^second . After 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 3%.

Example 8

Preparation of "AZO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 19.83g of tungsten chloride, 2.9749g of zinc nitrate, and 0.2251g of aluminum nitrate, dissolve them in 1000mL of ethylene glycol methyl ether, add 10mL of deionized water to it, and stir at room temperature for 2 hours to fully dissolve, and obtain tungsten, Composite sol of indium and tin; apply the obtained composite sol evenly on the transparent conductive oxide glass substrate by dipping or spin coating technology to form a gel film, dry it at 150°C for 10 minutes, and put it into a heat treatment furnace in an oxygen atmosphere at 200-300° C. for 1 h, then take it out, and cool it to room temperature in air to obtain the “AZO nanocrystal-WO ₃ amorphous” dual-phase composite film.

The film obtained in this example has an optical modulation contrast ΔT% in the visible light band of 72%, an optical modulation contrast ΔT% in the 1200nm wavelength band of 56%, and a 100×100mm film with a color change response time of 1 ^second . After 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 4%.

Example 9

Preparation of "AZO nanocrystalline-WO ₃ amorphous" electrochromic film:

Take 9.91g of tungsten chloride, 0.7437g of zinc nitrate, and 0.0563g of aluminum nitrate, dissolve them in 250mL of methanol, add 2.5mL of deionized water to it, and stir at room temperature for 2 hours to fully dissolve, and then obtain tungsten, indium, and tin. The composite sol of the composite sol; the obtained composite sol is evenly coated on the transparent conductive oxide glass substrate by dipping or spin-coating technology to form a gel film. It was kept in an oxygen atmosphere at ~300°C for 1 hour, then it was taken out, and air-cooled to room temperature to obtain an "AZO nanocrystalline-WO ₃ amorphous" dual-phase composite film.

The film obtained in this example has an optical modulation contrast ΔT% in the visible light band of 74%, an optical modulation contrast ΔT% in the 1200nm wavelength band of 50%, and a 100×100mm film with a color change response time of 1 ^second . After 2000 coloring and fading treatments , the charge storage capacity of the film decreased by only 3%.

comparative example

Preparation of amorphous WO ₃ electrochromic film:

Take 0.9914g of tungsten chloride, dissolve it in 50mL of methanol, stir it at room temperature for 2 hours to fully dissolve, and obtain the tungsten oxide precursor sol; adopt the dipping and pulling or spin coating technology, and evenly coat the obtained composite sol on the transparent conductive oxide glass Form a gel film on the substrate, dry it at 150°C for 10 minutes, put it into a heat treatment furnace and keep it in an oxygen atmosphere at 200-300°C for 1 hour, then take it out, and air cool it to room temperature to obtain an amorphous WO ₃ film.

The transmittance curves of the colored state and the faded state of the comparison film obtained in this example are shown in Figure 1, and the optical modulation contrast ΔT% in the visible light band is 40%; the optical modulation contrast ΔT% in the 1200nm wave band is 3% 100 × 100mm ² film color change response time 6s, the electrochromic response time chart of the film obtained in this embodiment is shown in Figure 2; after 2000 times of coloring and fading treatment, the charge storage capacity of the film decreased by 60%.

In the present invention, the tungsten oxide film is prepared as an amorphous film. Since the microstructure of the amorphous material is short-range disordered, it is easy to generate nano-channels in the amorphous tungsten oxide that are conducive to the entry and exit of lithium ions, while in the amorphous tungsten oxide Doping TCO nanocrystals into the tungsten matrix will increase the disordered structure inside the material and generate more nanoscale channels. In addition, TCO nanocrystals have near-infrared electrochromic properties. Doping TCO nanocrystals into tungsten oxide amorphous Among the materials, the formation of "TCO nanocrystalline-WO ₃ amorphous" composite film can not only improve the visible spectrum modulation ability of the tungsten oxide film and prolong the service life, but also improve its modulation ability in the near-infrared band, so that the tungsten oxide-based electric Chromogenic glass has higher spectral tuning and better thermal insulation performance.

Claims (3)

1. a kind of preparation method of nanocrystalline enhancing tungsten oxide electrochomeric films, it is characterised in that comprise the following steps that：

Step 1, after tungsten chloride and TCO being mixed with metal nitrate, it is dissolved in organic solvent, obtains mixed solution；Thereto plus Enter deionized water, stir 2h at normal temperatures, fully after dissolving, obtain complex sol；

The TCO metal nitrates, it is the mixture of nitric acid tin and indium nitrate；Or the mixture of nitric acid tin and antimony trichloride； Or the mixture of zinc nitrate and aluminum nitrate；The mol ratio of nitric acid tin, indium nitrate and tungsten chloride is 0.1:1:5~20；Or tri-chlorination The mol ratio of antimony, nitric acid tin and tungsten chloride is 0.04:1:10~100；Or aluminum nitrate:Zinc nitrate:The mol ratio of tungsten chloride is 0.06:1:5~20；

Step 2, using Best-Effort request or spin coating technique, by step 1 gained complex sol even application in transparent conductive oxide On glass substrate, gel mould is formed；

Step 3, step 2 gained gel mould is placed in 150 DEG C of environment after 10min, be put into heat-treatment furnace in 200~300 DEG C Oxygen atmosphere under be incubated 1 hour, be then drawn off, be air-cooled to room temperature, produce electrochomeric films.

2. a kind of preparation method of nanocrystalline enhancing tungsten oxide electrochomeric films according to claim 1, its feature exist In in step 1, organic solvent is one kind or any several with obtained by arbitrary proportion in methanol, ethanol and ethylene glycol monomethyl ether Mixture, the molar concentration of tungsten chloride is 0.05~0.15mol/L in gained mixed solution.

3. a kind of preparation method of nanocrystalline enhancing tungsten oxide electrochomeric films according to claim 1, its feature exist In in step 1, the volume ratio of deionized water and organic solvent is 1：100.