Electrochromic microporous molecular sieve for regulating near-infrared light and preparation method and application thereof

Abstract

The present invention discloses a preparation method of an electrochromic microporous molecular sieve for regulating near-infrared light, comprising: adding silicon powder, ammonium chloride powder, sodium fluoride and lithium chloride into an alumina crucible to obtain a mixture, and heat-treating the mixture under a nitrogen atmosphere to obtain lithium aluminum silicon oxide, wherein the mass ratio of the silicon powder, ammonium chloride, sodium fluoride and lithium chloride is 0.05-1:0.065-0.13:0.325-0.5:0.065-0.13. The preparation method can efficiently prepare a microporous molecular sieve that can be regulated by an electric field, and the present invention also provides a light microporous molecular sieve prepared by the preparation method of the light microporous molecular sieve that can be regulated by an electric field, and the application of the light microporous molecular sieve in near-infrared light regulation. The prepared microporous molecular sieve has good infrared light regulation performance after being subjected to an applied electric field.

Description

Technical Field

[0001] The invention belongs to the field of electrochromic materials, and in particular relates to an electrochromic microporous molecular sieve for regulating near-infrared light, and a preparation method and application thereof. Background Art

[0002] Electrochromic materials are smart materials that can control light with electric fields, and have very wide applications in daily life, such as flexible displays and smart glass. Visible to infrared band electrochromism can reduce electricity consumption and carbon emissions in residential and industrial production by exhibiting radiative heating or cooling in daily life. The research scope of visible electrochromism is wide, and materials span from inorganic compounds (e.g., Prussian blue analogs and WO3) to organic molecules and polymers (e.g., polyaniline) have reported their electrochromic properties. Compared with visible photoelectrochromism, although infrared electrochromism has been less studied, its optical and thermal applications have great potential. For example, infrared photoelectrochromic devices can be regulated to exhibit radiative heating or cooling on the earth, reducing electricity consumption and carbon footprint in residential and industrial settings. Materials showing regulation of infrared electrochromism are therefore obviously attractive. Therefore, materials that can exhibit excellent electrochromic properties in the visible to infrared band are of great potential in the future.

[0003] In recent years, several electrochromic materials with tunable infrared light have been reported, such as polyaniline and WO3. However, the use of water and polymers limits their application at high temperatures. In addition, such materials currently have disadvantages such as a narrow near-infrared tunable range. Therefore, electrochromic materials with high tunability in the visible and infrared spectral ranges are still sought after. As we all know, LTO has been widely used as an anode material for lithium-ion batteries. Recently, Professor Li Yuan's research group studied Li4Ti5O 12 (LTO) exhibits tunable emissivity or reflectivity from visible to infrared wavelengths. During the lithiation process, LTO changes from the delithiated state (Li4Ti5O 12 ) into the lithiated state (Li7Ti5O 12 ), which leads to a drastic change in electromagnetic properties. When embedded with lithium, LTO nanoparticles transform from ultra-broadband light reflectors to light absorbers and thermal radiators. The light reflectivity of the material is tunable in the sunlight, mid-wave infrared and long-wave infrared bands, respectively, and maintains excellent performance after a large number of cycles. Li4Ti5O 12 The nanoparticles have high reflectivity in the visible to infrared wavelengths, and Li7Ti5O 12The nanoparticles have high absorptivity or emissivity. Measurements of the spectral reflectance R(λ) confirmed that the perceptible tunability in the wavelength range (λ) of 0.4 μm to 11 μm is >0.4, that is, the material has ultra-wideband electrochromic properties and shows stable electrochromic behavior over a large number of cycles. The broadband electrochromic properties make it have good application prospects in infrared camouflage and space and environmental temperature control.

[0004] Based on the above concept, we designed a class of transition metal-free microporous molecular sieve materials LiAlSiO4 (LASO-1) and Li2Al2Si3O 10 (LASO-2) nanosheet material, which has a three-dimensional microporous channel structure, allows Li ions to be freely transported in the channel under voltage. Under different voltages, LASO exhibits the regulation characteristics of near-infrared light 0.5-2.0μm. Its characteristics are that under different voltages, there is little change in the visible light region, but there is a significant change in the near-infrared light region, which not only maintains the transparency of the material, but also can regulate the temperature changes caused by near-infrared light. Therefore, this has important application prospects in future automotive smart glass and building energy-saving materials. Summary of the invention

[0005] The present invention provides a method for preparing an electrochromic microporous molecular sieve for regulating near-infrared light. The preparation method can efficiently prepare a microporous molecular sieve that can be regulated by an electric field, namely a lithium aluminum silicon oxide compound. The prepared microporous molecular sieve has good infrared light regulation performance under the action of an external electric field.

[0006] A method for preparing a microporous molecular sieve that regulates near-infrared light electrochromism, comprising:

[0007] Silicon powder, ammonium chloride powder, sodium fluoride and lithium chloride are added into an alumina crucible to obtain a mixture, and the mixture is heat-treated under a nitrogen atmosphere to obtain lithium aluminum silicon oxide, wherein the mass ratio of the silicon powder, ammonium chloride, sodium fluoride and lithium chloride is 0.05-1:0.065-0.13:0.325-0.5:0.065-0.13.

[0008] The present invention can obtain stable lithium aluminum silicon oxide with less impurities without adding an Al source. By adding ammonium chloride and sodium fluoride, the generation of impurities can be reduced and the yield of lithium aluminum silicon oxide can be increased.

[0009] Further, the step of adding silicon powder, ammonium chloride powder, sodium fluoride and lithium chloride into the alumina crucible comprises:

[0010] First, add silicon powder into the alumina crucible, then add ammonium chloride powder, sodium fluoride, and lithium chloride into the alumina crucible and spread on the surface of silicon powder. Since silicon powder has a small particle size and light weight, this placement can prevent silicon powder from being blown away by nitrogen during the experiment, causing unnecessary experimental errors.

[0011] Furthermore, the content of aluminum oxide in the aluminum oxide crucible is not less than 99%.

[0012] Furthermore, the heat treatment process is as follows: heating from room temperature, after 50 minutes of heating time, the temperature in the furnace is raised to 470°C; keeping at 470°C for 30 minutes, heating for 30 minutes, raising the temperature in the furnace to 740°C; keeping at 740°C for 30 minutes, heating for 35 minutes, raising the temperature to 1050°C; keeping at 1050°C for 180 minutes and then stopping heating. After the temperature in the furnace drops to 50°C.

[0013] The present invention also provides an electrochromic microporous molecular sieve, which is prepared by the preparation method of the electrochromic microporous molecular sieve capable of regulating near-infrared light.

[0014] Furthermore, the molecular formula of the electrochromic microporous molecular sieve is Li a Al b Si c O d , wherein 1≤a≤2, 1≤b≤2, 1≤c≤3, 4≤d≤10, the surface of the microporous molecular sieve has a microporous structure, and the Li element is embedded in the surface of the microporous structure.

[0015] Furthermore, the molecular formula of the electrochromic microporous molecular sieve is LiAlSiO4 or Li2Al2Si3O 10 .

[0016] The present invention also provides the application of the electrochromic microporous molecular sieve in near-infrared light regulation, including:

[0017] (1) adding the electrochromic microporous molecular sieve to a perfluorosulfonic acid polymer solution to obtain a mixed solution A, and subjecting the mixed solution A to ultrasonic treatment;

[0018] (2) applying the mixed solution A obtained in step (1) dropwise onto the polished surface of the metal titanium, drying to obtain the metal titanium with the electrochromic microporous molecular sieve adhered thereto, and clamping the metal titanium with the electrochromic microporous molecular sieve adhered thereto on the glassy carbon electrode;

[0019] (3) using the glassy carbon electrode obtained in step (2) as a working electrode, Ag-AgCl as a reference electrode, and a carbon rod as an auxiliary electrode, and applying a constant voltage to detach some of the Li ions in the microporous molecular sieve adhered to the surface of the metal titanium;

[0020] (4) adding the pressurized titanium adhered electrochromic microporous molecular sieve obtained in step (3) into anhydrous ethanol, performing ultrasonic treatment to obtain a mixed solution B, dropping the mixed solution B onto a cover glass and drying it to obtain a near-infrared light control sample, and controlling the irradiated near-infrared light through the near-infrared light control sample.

[0021] The present invention separates some Li ions from the optical microporous molecular sieve by applying voltage, and the optical microporous molecular sieve has more electrons, so that the microporous molecular sieve is transformed from a semiconductor state to a metallic state. In the near-infrared light wave range, the microporous molecular sieve in the metallic state has higher light absorption capacity and lower light reflection capacity, thereby being able to regulate the absorption and reflection of near-infrared light waves.

[0022] Furthermore, the wavelength of the near-infrared light is 200nm-2500nm.

[0023] Furthermore, the near-infrared light regulation sample has an absorbance value of 0.60-0.74 to near-infrared light.

[0024] Furthermore, the near-infrared light control sample has a reflectance value of 0-0.4 for near-infrared light. Furthermore, a constant voltage is applied by a constant voltage method to detach some Li ions in the microporous molecular sieve adhered to the surface of the metal titanium, and the constant voltage is -0.1-(-1.5) V. When the negative voltage applied is too small, the amount of Li ions detached from the microporous molecular sieve is small, and its light absorption capacity is still poor; when the applied voltage is too high, the electrode is easily damaged.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) Compared with the prior art of adding alumina to provide an aluminum source, the present invention provides an aluminum source through an alumina crucible, so that the formed optical microporous molecular sieve has fewer impurities, and by adding ammonium chloride and sodium fluoride, the calcination temperature of lithium aluminum silicon oxide can be reduced, saving the synthesis cost.

[0027] (2) The present invention applies voltage to the photoporous molecular sieve, causing some Li ions to detach from the photoporous molecular sieve. The photoporous molecular sieve has excess electrons, causing the photoporous molecular sieve to transform from a semiconductor to a metallic state, thereby having a stronger light absorption ability and a weaker light reflection ability under near-infrared light waves. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is the XRD pattern of LiSiAlO4 prepared in Example 1 of the present invention;

[0029] Figure 2 Li2Al2Si3O prepared in Example 2 of the present invention10 XRD pattern of

[0030] Figure 3 Li2Al2Si3O prepared in Example 2 of the present invention 10 The morphology and high-resolution images;

[0031] Figure 4 XRD diagram of SiO2 prepared in Comparative Example 1 of the present invention;

[0032] Figure 5 The ultraviolet absorption and reflection diagram of the LiSiAlO4 near-infrared light control sample prepared in Application Example 1 of the present invention is as follows: Figure 5 (a) is the UV absorption graph, Figure 5 (b) is the UV reflection graph;

[0033] Figure 6 Li2Al2Si3O prepared in Application Example 2 of the present invention 10 Ultraviolet absorption and reflection diagram of near-infrared light-controlled samples. Figure 6 (a) is the UV absorption graph, Figure 6 (b) is the UV reflection graph. DETAILED DESCRIPTION

[0034] The present invention is further described by the following examples, which are only intended to explain the present invention and are not intended to limit its contents.

[0035] Example 1

[0036] Weigh 0.05g Si, 0.065g NaF, 0.325g NH4Cl and 0.065g LiCl in sequence, pour Si, NH4Cl, NaF and LiCl into the crucible in that order, mix the four chemicals evenly with a small medicine spoon, and cover the crucible. Put the crucible in the center of the vacuum tube furnace, perform three gas washing operations, and put the tube furnace in a nitrogen atmosphere.

[0037] The heating parameters of the tube furnace were set so that the heating process was as follows: heating started at 20°C, heated to 470°C after 50 minutes, and kept at 470°C for 30 minutes; the temperature was raised to 740°C after 30 minutes of heating, and kept at 740°C for 30 minutes; the temperature was raised to 1050°C after 35 minutes of heating, and stopped heating after being kept at 1050°C for 180 minutes. The sample was taken out when it cooled naturally to about 50°C to obtain fine white particles.

[0038] The product was subjected to X-ray diffraction analysis, and it was found that the main peak was LiAlSiO4, and its XRD diffraction peak could correspond to the PDF card 73-0256 of LiAlSiO4, such as Figure 1 shown.

[0039] Example 2

[0040] Weigh 0.1g Si, 0.13g NaF, 0.5g NH4Cl and 0.13g LiCl in sequence. Pour the weighed Si into the crucible, then pour NH4Cl, NaF and LiCl into the crucible in order, and use a small medicine spoon to stir the four medicines to make them evenly mixed. Cover the lid of the crucible and put it in the middle of the vacuum tube furnace. The heating of the medicine requires to be carried out in a nitrogen atmosphere, so the tube furnace is purged three times. After the purge is completed, set the heating parameters of the tube furnace and start heating. The specific heating process is to start heating from room temperature, and after 50 minutes of heating time, the temperature in the furnace is raised to 470℃; keep it at 470℃ for 30 minutes, and then heat it for 30 minutes to raise the temperature in the furnace to 740℃; keep it at 740℃ for 30 minutes, and then heat it for 35 minutes to raise the temperature to 1050℃; keep it at 1050℃ for 180 minutes and stop heating. After the temperature in the furnace dropped to 50°C, the tube furnace was closed and the sample was taken out to obtain fine white particles. The product was ground in a mortar and then subjected to X-ray diffraction analysis, and it was found that the product was Li2Al2Si3O 10 Its XRD diffraction peak corresponds to Li2Al2Si3O 10 PDF card 25-1183, such as Figure 2 shown.

[0041] The morphology of the obtained product is shown in Figure 3 As shown, Figure 3 (a) and Figure 3 (b) is Li2Al2Si3O 10 The TEM observation image shows that Li2Al2Si3O 10 There are very few areas in the microscopic morphology that are not square, such as Figure 3 As shown in the upper left corner of (a), the grain shapes in the rest of the area are all regular squares. In order to obtain more specific unit cell parameters, high-resolution transmission electron microscopy (HRTEM) was performed on it. The results are shown in Figure 3 c- Figure 3 The calculation results show that the interplanar spacing of most samples is 0.348nm, 0.205nm, 0.209nm, and 0.339nm, which are respectively consistent with Li2Al2Si3O 10 The (101) crystal plane in the standard PDF card (201) crystal plane The good correspondence further illustrates that Li2Al2Si3O 10 The structure is correct; the surface of the microporous molecular sieve has a microporous structure, and the Li element is embedded in the surface of the microporous structure.

[0042] Comparative Example 1

[0043] Weigh 0.1g silicon powder (Si), 0.13g sodium fluoride (NaF), 0.65g ammonium chloride (NH4Cl), and 0.14g lithium chloride (LiCl) in sequence, pour NH4Cl into the crucible and place it at the bottom of the crucible; pour the weighed Si, NaF, and LiCl into the crucible in order, and use a small medicine spoon to mix the three chemicals on the upper layer evenly. Put the crucible in the center of the vacuum tube furnace, perform three gas washing operations after installation, exhaust the air in the glass tube, and sinter the crucible in a nitrogen atmosphere. Set the heating parameters of the vacuum tube furnace so that the heating process starts heating at 20℃, heats to 1050℃ after 115min, keeps warm at 1050℃ for 180min, and then starts natural cooling. When the furnace temperature cools to a safe temperature, turn off the power of the tube furnace, take the crucible out of the tube furnace, and get some white particles. After grinding, perform X-ray diffraction analysis, and it is found that the main phase is silicon dioxide. Its XRD diffraction peaks can correspond to PDF card 42-1401 of SO2, such as Figure 4 shown.

[0044] Application Example 1

[0045] Take 20 mg of LiAlSiO4 obtained by Example 1, pour it into a centrifuge tube, add 3 mL of anhydrous ethanol, and then add 10 μL of nafion perfluorosulfonic acid polymer solution. Put the mixed solution into an ultrasonic cleaner for ultrasound to disperse the nafion solution evenly. Cut a small piece of titanium sheet with scissors, and polish it with 400 mesh, 1200 mesh, and 1600 mesh sandpaper respectively to remove the oxide layer on its surface. After the surface of the titanium sheet is polished to smooth, bend it 90° to facilitate electrochemical experiments. Use a dropper to titrate the dispersed mixed solution together with LiAlSiO4 on the titanium sheet, and use an infrared drying lamp to dry it, so that LiAlSiO4 can adhere to the titanium sheet. Repeat this operation to complete the titration of LiAlSiO4. Use a carbon rod as an auxiliary electrode, Ag-AgCl as a reference electrode, and a glassy carbon electrode clip as a working electrode. Use a glassy carbon electrode clamp to clamp the titanium sheet with LiAlSiO4 titrated, and perform a constant potential IT experiment to extract Li. The experimental environment is 0.5 mol L -1 of Na2SO4 solution, the voltage was -1.5V, and the time was 180min.

[0046] Remove the titanium sheet sample after extraction, put it into a centrifuge tube, add an appropriate amount of anhydrous ethanol for ultrasonic treatment, so that the sample adhering to the titanium sheet falls off, and obtain a mixed solution of the titanium sheet sample after extraction and anhydrous ethanol. Then use a dropper to absorb about 5 mg of the mixed solution and drop it on the cover glass. After drying, the near-infrared light regulation sample is obtained. The same method is used to prepare the ultraviolet absorption sample without extraction experiment, and the ultraviolet absorption test is performed on both, and the test wavelength range is 2500-200nm. The test results are as follows Figure 5 As shown, the UV absorption results are as follows Figure 5 As shown in (a), it can be seen that before the voltage is applied, the absorbance of LiAlSiO4 does not change much in the range of 723-2000nm, and fluctuates between 0.64-0.65. When the wavelength range is 355-723nm, the absorbance of LiAlSiO4 increases greatly, from 0.60 to 0.65. For LiAlSiO4 after the voltage is applied, although the absorbance at the wavelength of 420-1078nm is smaller than that before the voltage is applied, it shows an upward trend at 355-1960nm, and after 1078nm, the absorbance of LiAlSiO4 subjected to IT experiment is greater than that of LiAlSiO4 not subjected to IT experiment. According to the formula R=10 -A (where R is reflectance and A is absorbance) can be converted into Figure 5 (b) shows a reflection graph that is opposite to the absorbance. In the wavelength range of 355-723nm, the reflectivity of LiAlSiO4 decreases significantly, from 0.34 to 0.31. In the range of 723-2000nm, the reflectivity of LiAlSiO4 changes little. After applying voltage, the reflectivity of LiAlSiO4 shows a downward trend in the band of 355-1960nm. This shows that applying voltage can improve the light absorption performance of LiAlSiO4, reduce its reflection in the band with larger wavelengths, and enhance its absorption capacity.

[0047] Application Example 2

[0048] Take 20 mg Li2Al2Si3O 10 Pour into a centrifuge tube, drip 3mL of anhydrous ethanol, use a microinjector to take 10μL of nafion solution and drip it into the centrifuge tube, put the centrifuge tube into an ultrasonic cleaner for ultrasonication to disperse the mixed solution evenly. Take a small piece of titanium sheet and polish it with 400 mesh, 1200 mesh, and 1600 mesh sandpaper in turn to remove the oxide layer on the surface of the titanium sheet. After the surface of the titanium sheet is polished, bend it 90° for electrochemical experiments. 10 Titrate on a titanium sheet and dry it with an infrared lamp. Repeat the titration operation until 5 mg of Li2Al2Si3O adheres to the titanium sheet. 10Carbon rod, Ag-AgCl and glassy carbon electrode holder were used as auxiliary electrode, reference electrode and working electrode respectively. -1 In the Na2SO4 solution environment, use a glassy carbon electrode to clamp the titrated Li2Al2Si3O 10 The titanium sheet was subjected to an IT experiment with a voltage of -1.5V and a duration of 180min.

[0049] Remove the titanium sheet sample after Li extraction from the glassy carbon electrode clamp, put it into a centrifuge tube, add an appropriate amount of anhydrous ethanol, and then put it into an ultrasonic cleaner for ultrasonic treatment, so that the sample adhering to the titanium sheet is dispersed in the anhydrous ethanol to obtain a mixed solution of the sample and anhydrous ethanol. The mixed solution is titrated onto a cover glass and dried to obtain a near-infrared light control sample. The same method is used to prepare a sample that has not undergone IT experiment, and both are tested for ultraviolet absorption. The test wavelength range is 2500-200nm. Figure 6 As shown, the UV absorption results are as follows Figure 6 As shown in (a), it can be seen that before the voltage is applied, Li2Al2Si3O 10 The absorbance of Li2Al2Si3O 10 The absorbance of Li2Al2Si3O increased significantly from 0.60 to 0.63. 10 Although the absorbance at wavelengths of 370-840nm is smaller than that before voltage application, it shows an upward trend at 370-1960nm, and after 840nm, the Li2Al2Si3O 10 The absorbance of Li2Al2Si3O 10 The absorbance is greater, and with the increase of IT experimental voltage, when the voltage of -0.5V or -1.5V is used for the experiment, Li2Al2Si3O 10 The absorbance of Li2Al2Si3O 10 The absorbance in the 370-600nm band is not much different, but the light absorption in the 370-1960nm band shows an upward trend. According to the formula R = 10 -A (where R is reflectance and A is absorbance) can be converted into Figure 6 (b) shows the reflectance graph, which is opposite to the absorbance. In the wavelength range of 367-696nm, Li2Al2Si3O 10 The reflectivity of Li2Al2Si3O 10 The reflectivity of Li2Al2Si3O10 The reflectivity of Li2Al2Si3O 10 The light absorption performance of the material can be improved, reducing its reflection of light in the longer wavelength band and enhancing its absorption capacity, making it better able to absorb light in the longer wavelength band.

Claims

1. A method for preparing a microporous molecular sieve for regulating near-infrared electrochromic properties, characterized in that: include: Add silicon powder, ammonium chloride powder, sodium fluoride and lithium chloride into an alumina crucible to obtain a mixture, and heat-treat the mixture under a nitrogen atmosphere to obtain lithium aluminum silicon oxide, wherein the mass ratio of silicon powder, ammonium chloride, sodium fluoride and lithium chloride is 0.05-1:0.065-0.13:0.325-0.5:0.065-0.13; The step of adding silicon powder, ammonium chloride powder, sodium fluoride and lithium chloride into an alumina crucible comprises: First, add silicon powder into an alumina crucible, then add ammonium chloride powder, sodium fluoride, and lithium chloride into the alumina crucible and spread on the surface of silicon powder; Or pour Si, NH4Cl, NaF, and LiCl into a crucible, use a small medicine spoon to mix the four chemicals evenly, and cover the crucible with a lid.

2. The method for preparing the electrochromic microporous molecular sieve for regulating near-infrared light according to claim 1, characterized in that: The content of aluminum oxide in the aluminum oxide crucible is not less than 99%.

3. An electrochromic microporous molecular sieve, characterized in that: The method for preparing a microporous molecular sieve for regulating near-infrared electrochromism according to any one of claims 1 to 2 is used.

4. The electrochromic microporous molecular sieve according to claim 3, characterized in that: The molecular formula of the electrochromic microporous molecular sieve is Li a Al b Si c O d , wherein 1≤a≤2, 1≤b≤2, 1≤c≤3, 4≤d≤10, the surface of the microporous molecular sieve has a microporous structure, and the Li element is embedded in the surface of the microporous structure.

5. The electrochromic microporous molecular sieve according to claim 3, characterized in that: The molecular formula of the electrochromic microporous molecular sieve is LiAlSiO4 or Li2Al2Si3O 10 .

6. An application of the electrochromic microporous molecular sieve according to any one of claims 3 to 5 in near-infrared light regulation, comprising: (1) adding the electrochromic microporous molecular sieve to a perfluorosulfonic acid polymer solution to obtain a mixed solution A, and subjecting the mixed solution A to ultrasonic treatment; (2) applying the mixed solution A obtained in step (1) dropwise onto the polished surface of the metal titanium, drying to obtain the metal titanium with the electrochromic microporous molecular sieve adhered thereto, and clamping the metal titanium with the electrochromic microporous molecular sieve adhered thereto on the glassy carbon electrode; (3) using the glassy carbon electrode obtained in step (2) as a working electrode, Ag-AgCl as a reference electrode, and a carbon rod as an auxiliary electrode, and applying a constant voltage to detach some of the Li ions in the microporous molecular sieve adhered to the surface of the metal titanium; (4) adding the pressurized titanium adhered electrochromic microporous molecular sieve obtained in step (3) into anhydrous ethanol, performing ultrasonic treatment to obtain a mixed solution B, dropping the mixed solution B onto a cover glass and drying it to obtain a near-infrared light control sample, and controlling the irradiated near-infrared light through the near-infrared light control sample.

7. The use of the electrochromic microporous molecular sieve in near-infrared light regulation according to claim 6, characterized in that: The absorption value of the near-infrared light regulating sample to near-infrared light is 0.60-0.74, and the reflection value of the near-infrared light regulating sample to near-infrared light is 0-0.

4.

8. The use of the electrochromic microporous molecular sieve in near-infrared light regulation according to claim 6, characterized in that: A constant voltage is applied by a constant voltage method to detach part of the Li ions in the microporous molecular sieve adhered to the surface of the metal titanium, wherein the constant voltage is -0.1-(-1.5)V.

Images