Sulfide-based trinickel disulfide electrochromic film and preparation method thereof

Abstract

The invention relates to the technical field of materials, in particular to a trinickel disulfide film based on sulfide and a preparation method thereof and application of the trinickel disulfide film to the field of electrochromism for the first time. The conventional electrochromic inorganic material mainly focuses on the research of oxides, and tends to be mature after many years of research, and has certain limitation on the selection of the research of the electrochromic material, so that the research of the electrochromic inorganic material is facilitated on the basis of the reasons such as the limitation. The prepared sulfide-based trinickel disulfide film deposited on the FTO glass can realize a color fading electrochromic phenomenon by applying voltage in a potassium hydroxide solution, and the sulfide-based trinickel disulfide electrochromic film is simple to prepare, has good conductivity and high transmittance, and can be applied to the field of electrochromic devices. The near-infrared modulated light range is large (the near-infrared modulated light range can reach 84.9% at the position of 520 nm), the response time is short, the stability is good, and the near-infrared modulated light can be applied to electrochromic devices and related fields.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of materials, in particular to a sulfide-based trinickel disulfide electrochromic film and a preparation method thereof. BACKGROUND

[0002] Since the 1960s, electrochromic phenomenon has attracted much attention because of its unique color-changing performance and wide application prospects. Electrochromic materials exhibit reversible color changes under the action of an applied electric field through redox reactions, which makes them have great application potential in smart windows, displays and energy storage. With the rapid development of material science and nanotechnology, the research on electrochromic materials has made remarkable progress, and more and more new types of electrochromic materials have been developed. According to their chemical composition and structural characteristics, they can be mainly divided into three categories: organic materials, inorganic materials and composite materials. In addition to organic materials and composite materials, in the field of inorganic materials, the main focus is on oxide materials such as WO3, NiO, V2O5 and MnO2. The electrochromic performance of sulfides is still in the stage of less research. Although there are sulfides in the previously reported articles about the electrochromic performance of sulfides, it can be found that the main color-changing material is still an oxide.

[0003] The application provides a sulfide-based trinickel disulfide electrochromic film and a preparation method thereof, which proves that sulfides can also exhibit electrochromism through redox reactions, which is different from traditional oxides and has superior performance. By electrodeposition of a trinickel disulfide film on FTO conductive glass, color changes occur in the process of embedding and removing potassium ions in a potassium hydroxide electrolyte. By adjusting experimental parameters, an electrochromic film with high transmittance, large light modulation amplitude and good cycle stability can be realized. Moreover, this method has high repeatability, is simple to manufacture, low in price, high in transmittance and suitable for depositing large-size areas. SUMMARY

[0004] In view of the deficiencies of the prior art, the application provides a sulfide-based trinickel disulfide electrochromic film and a preparation method thereof, which proves that sulfides can also exhibit electrochromism through redox reactions, which is different from traditional oxides and has superior performance. By electrodeposition of a trinickel disulfide film on FTO conductive glass, color changes occur in the process of embedding and removing potassium ions in a potassium hydroxide electrolyte. By adjusting experimental parameters, an electrochromic film with high transmittance, large light modulation amplitude and good cycle stability can be realized. Moreover, this method has high repeatability, is simple to manufacture, low in price, high in transmittance and suitable for depositing large-size areas.

[0005] To achieve the above object, the application is implemented by the following technical scheme: a preparation method of a sulfide-based trinickel disulfide electrochromic film, comprising the following steps: S1. Dissolve thiourea and nickel chloride hexahydrate in deionized water to obtain a precursor solution.

[0006] S2. In a three-electrode system, use the precursor solution prepared in the foregoing as an electrolyte, fluorine-doped tin oxide (FTO) transparent conductive glass as a working electrode, foamed nickel as a counter electrode, and Ag / AgCl electrode as a reference electrode to prepare a trinickel disulfide film by constant voltage electrodeposition, thereby obtaining FTO glass with a trinickel disulfide film.

[0007] S3. Dissolve potassium hydroxide in deionized water to obtain a potassium hydroxide electrolyte.

[0008] S4. Adhere the FTO glass with a trinickel disulfide film prepared in S2 and clean FTO glass together by gel to obtain a trinickel disulfide electrochromic device. S5. Inject the solution prepared in S3 into the device prepared in S4 to obtain a trinickel disulfide electrochromic device based on a potassium hydroxide electrolyte.

[0009] Preferably, the concentration of thiourea in the S1 step is 150 mmol / L, and the concentration of nickel chloride hexahydrate is 4 mmol / L.

[0010] Preferably, the constant voltage deposition voltage in the S2 step is -0.5 V, and the deposition time is 5 h.

[0011] Preferably, the potassium hydroxide electrolyte in the S3 step is a 1M ion solution in deionized water.

[0012] Working principle: By applying an external voltage to drive potassium ions in the electrolyte, the potassium ions enter the trinickel disulfide film to produce an oxidation-reduction reaction, thereby changing the optical properties of the material.

[0013] The application provides a trinickel disulfide electrochromic film based on sulfide electrodeposition and a preparation method thereof. 1. The trinickel disulfide film obtained by electrodeposition has a very high bleached state transmittance and a deep color in the colored state, and the near-infrared modulated light amplitude is as high as 84.9%.

[0014] 2. The trinickel disulfide film prepared by electrodeposition has good stability and can be used for a long time.

[0015] 3. The trinickel disulfide electrochromic film prepared by electrodeposition and working in an aqueous potassium hydroxide electrolyte has a fast response speed and a high coloring efficiency, and can further increase the light modulation amplitude in response to the power-on time.

[0016] 4、The present application adjusts the coloring and fading of the electrochromic film by electric energy, has simple preparation process, low material price, is easy to obtain and has low cost; further reduces the consumption of energy and makes up for the application of sulfide in the electrochromic field, thereby increasing the research range. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A scanning electron microscope photo of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application; Figure 2 An EDS spectrum of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application; Figure 3 An XRD curve of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application; Figure 4 A CV curve of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application; Figure 5 Effect diagrams of the fading state (a) and the coloring state (b) of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application; Figure 6 A transmittance curve of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application; Figure 7 A response time curve of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application; Figure 8 A cycle time curve of the electrochromic film based on trinickel disulfide prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0019] Example 1: (1) 95.06 mg of nickel chloride hexahydrate and 1.1418 g of thiourea were dissolved in 100 ml of deionized water, and stirred at 700 r / min for about 30 min.

[0020] (2) The FTO conductive glass to be electrodeposited was cut into appropriate size, washed with detergent, and then ultrasonically cleaned with ethanol and deionized water for 10 min, and then dried in an oven at 60℃.

[0021] (3) The foamed nickel welded with the nickel strip is put into deionized water for ultrasonic cleaning for 20 min and dried in an oven at 60°C.

[0022] (4) The solution obtained in (1) is poured into an electrolytic cell, a three-electrode system is adopted, the FTO glass obtained in (2) is used as a working electrode, the foamed nickel obtained in (3) is used as a counter electrode, and Ag / AgCl is used as a reference electrode. Constant voltage deposition is used in a Chenhua electrochemical workstation, the deposition voltage is -0.5 V~0 V, and the deposition time is 5 h-1 h.

[0023] (5) The FTO glass obtained by electrodeposition in (4) is washed with deionized water and dried at room temperature.

[0024] Example 2: (1) 950.6 mg of nickel chloride hexahydrate and 11.418 g of thiourea are dissolved in 100 ml of deionized water, and stirred at 700 r / min for about 30 min.

[0025] (2) The FTO conductive glass to be electrodeposited is cut into a proper size, washed with detergent, and then ultrasonically cleaned with ethanol and deionized water for 10 min respectively, and then dried in an oven at 60°C.

[0026] (3) The foamed nickel welded with the nickel strip is put into deionized water for ultrasonic cleaning for 20 min and dried in an oven at 60°C.

[0027] (4) The solution obtained in (1) is poured into an electrolytic cell, a three-electrode system is adopted, the FTO glass obtained in (2) is used as a working electrode, the foamed nickel obtained in (3) is used as a counter electrode, and Ag / AgCl is used as a reference electrode. Constant voltage deposition is used in a Chenhua electrochemical workstation, the deposition voltage is -0.5 V ~ 0 V, and the deposition time is 0.5 h-1 h.

[0028] (5) The FTO glass obtained by electrodeposition in (4) is washed with deionized water and dried at room temperature.

[0029] Example 3: (1) 950.6 mg of nickel chloride hexahydrate and 11.418 g of thiourea are dissolved in 100 ml of deionized water, and stirred at 700 r / min for about 30 min.

[0030] (2) The FTO conductive glass to be electrodeposited is cut into a proper size, washed with detergent, and then ultrasonically cleaned with ethanol and deionized water for 10 min respectively, and then dried in an oven at 60°C.

[0031] (3) The foamed nickel welded with the nickel strip is put into deionized water for ultrasonic cleaning for 20 min and dried in an oven at 60°C.

[0032] (4) Pour the solution obtained in (1) into an electrolytic cell, and use a three-electrode system, wherein the FTO glass obtained in (2) is used as a working electrode, the foamed nickel obtained in (3) is used as a counter electrode, and Ag / AgCl is used as a reference electrode. Use a constant voltage deposition on a Chenhua electrochemical workstation, the deposition voltage is -0.5 V ~ 0 V, and the deposition time is 1 h-2 h.

[0033] (5) The FTO glass obtained by electrodeposition in (4) is washed with deionized water and dried at room temperature.

[0034] As shown in Figures 1-8 , the scanning electron microscope photo of the sulfide-based trinickel disulfide electrochromic film prepared in Example 1 is shown in Figure 1 , which is a dense linear shape. Figure 2 is the EDS spectrum of the sulfide-based trinickel disulfide electrochromic film prepared in Example 1, which confirms the element content. Figure 3 is the XRD spectrum of the sulfide-based trinickel disulfide electrochromic film prepared in Example 1. The scanning cyclic voltammetry curve (CV) of the sulfide-based trinickel disulfide electrochromic glass obtained in Example 1 is shown in Figure 4 , 1.5 V is selected as the coloring voltage, -1.5 V is selected as the bleaching voltage, the electrochemical workstation is used in combination with an ultraviolet spectrophotometer, and the test is performed in the wavelength range of 400-800 nm, Figure 5 is the coloring (a) and bleaching (b) change diagram of the sulfide-based trinickel disulfide electrochromic glass prepared in Example 1. Figure 6 is the transmittance curve, from which it can be seen that the device turns into black brown under a positive voltage of 1.5 V, and turns into colorless when a negative voltage of -1.5 V is applied. The modulation amplitude of the transmittance reaches a maximum at a wavelength of 520 nm, about 84.9%. The electrochromic glass jumps between 1.5 V and -1.5 V every 25 s to form a light response curve, and all data are measured at 520 nm. Figure 7 is the response time curve of the sulfide-based trinickel disulfide electrochromic film prepared in Example 1, and the coloring time of the trinickel disulfide electrochromic glass is about 16.3 s and the bleaching time is 22.4 s when the light modulation change value reaches 90%, which is calculated. Figure 8 is the cycle time curve of the sulfide-based trinickel disulfide electrochromic film prepared in Example 1, and there is no attenuation phenomenon at 8000 s of cycle.

[0035] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. An electrochromic film based on nickel disulfide sulfide, characterized by: The electrochromic film is prepared by using thiourea, nickel chloride hexahydrate and potassium hydroxide.

2. The method for preparing a nickel disulfide electrochromic film according to claim 1, wherein: The film preparation method of the electrochromic film is as follows: S1: mixing and dissolving thiourea, nickel chloride hexahydrate and deionized water to obtain a precursor solution; S2: In a three-electrode system, the precursor solution of a certain concentration prepared in S1 is used as the electrolyte, FTO transparent conductive glass is used as the working electrode, nickel foam is used as the counter electrode, and Ag / AgCl electrode is used as the reference electrode. A nickel disulfide thin film is prepared by constant voltage electrodeposition to obtain FTO glass with a nickel disulfide thin film. S3: Mixing and dissolving potassium hydroxide and deionized water to obtain a potassium hydroxide electrolyte; S4: bonding the FTO glass with nickel disulfide thin film prepared in S2 and S3 and the clean FTO glass together through gel to obtain a nickel disulfide electrochromic device; S5: The solution prepared in S3 is injected into the device prepared in S4 to obtain a nickel disulfide electrochromic device based on potassium hydroxide electrolyte.

3. The method for preparing a nickel disulfide electrochromic film according to claim 2, wherein: In step S1, the concentration of thiourea is 150 mmol / L, and the concentration of nickel chloride hexahydrate is 4 mmol / L.

4. The method for preparing a nickel disulfide electrochromic thin film according to claim 2, wherein: In the step S2, the constant voltage deposition voltage is -0.5 V and the deposition time is 5 h.

5. The method for preparing a nickel disulfide electrochromic thin film according to claim 2, wherein: In the step S3, the potassium hydroxide electrolyte is a 1M ionic aqueous solution.

6. Application of the nickel disulfide-based electrochromic film prepared according to the preparation method according to any one of claims 2 to 5 in the fields of smart glass and display.

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