Preparation method of high-efficiency anti-reflection film for photovoltaic glass and film

Abstract

The invention discloses a method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass, comprising the steps of cleaning and pre-treating the photovoltaic glass; preparing a composite sol using tetraethyl silicate, boric acid, hydrochloric acid, F127, anhydrous ethanol and deionized water as raw materials through a sol-gel method, and then adding tetraethyl silicate and methyltriethoxysilane for modification after aging to prepare an anti-reflection and anti-reflection coating solution; and preparing an anti-reflection and anti-reflection film on the surface of the photovoltaic glass through pulling and high-temperature tempering treatment. The film has SiO2 as a main component and is formed by disorderly accumulation of SiO2 particles of two different sizes. The special pore structure of the film ensures that the film has high transmittance in the visible light band and low transmittance in the near-infrared band, thereby achieving the purpose of reducing the temperature rise of photovoltaic modules and ensuring efficient operation of the photovoltaic modules. The method is low in cost and simple in process, and is conducive to industrial promotion.

Description

Technical Field

[0001] This patent relates to the technical field of preparation of anti-reflection and anti-reflection films, and specifically to a method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass. Background Art

[0002] Solar energy is a renewable energy source with the advantages of being clean, safe, abundant, and widespread. Photovoltaic power generation brings significant economic and social benefits and plays an important role in my country's energy strategy. Improving the utilization rate of sunlight, photoelectric conversion efficiency, and reducing manufacturing costs are key issues that need to be addressed in the development of solar cell technology and the photovoltaic industry. Solar cells can be divided into two categories: crystalline silicon cells and thin-film cells. Both use photovoltaic glass as a packaging cover. Therefore, the glass cover is one of the important factors affecting the utilization rate and conversion efficiency of sunlight. Relevant research shows that increasing the transmittance of the glass cover by 1% can increase the overall efficiency of the system by 2%. By preparing a high-performance anti-reflection and anti-reflection coating on the surface of the photovoltaic glass cover, the reflection of sunlight on the photovoltaic glass can be significantly reduced, increasing the utilization rate of solar energy and improving the photoelectric conversion efficiency.

[0003] Antireflective coatings, also known as AR coatings, are applied to the surface of optical components to effectively reduce light reflection at interfaces and improve transmittance. By preparing a nanometer-thick thin film coating on the surface of a photovoltaic glass cover, the overall transmittance can be effectively improved. However, all AR coatings currently developed and applied have good antireflection effects across the entire spectrum (380-1100nm). While transmittance increases, the system's internal temperature rises significantly due to increased heat absorption. Increased transmittance in the near-infrared short-wavelength band (780-1100nm) is the primary factor contributing to the temperature increase in photovoltaic modules. However, the transmittance curve of existing coatings shows a smooth decline within the near-infrared short-wavelength band. This temperature increase reduces the conversion efficiency of photovoltaic modules, thereby decreasing the efficiency of solar energy output. Therefore, there is an urgent need to develop a method for preparing an AR film that achieves a smaller increase in transmittance in the near-infrared band, a larger increase in transmittance in other bands, and a low manufacturing cost and simple construction. Summary of the Invention

[0004] In order to overcome the shortcomings of existing anti-reflection and anti-reflection films, the present invention provides a method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass, which can be used to prepare an anti-reflection and anti-reflection film on the surface of photovoltaic cover glass, which has a smaller increase in anti-reflection rate in the near-infrared short-wave band and a larger increase in anti-reflection rate in other bands.

[0005] The technical problem solved by the present invention is achieved by the following technical solutions:

[0006] First, the present application provides a method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass, comprising the following steps:

[0007] (1) Pretreatment of photovoltaic glass: Use deionized water, dilute hydrochloric acid and anhydrous ethanol to clean, soak and dry the photovoltaic glass substrate in sequence; the pretreatment step can decontaminate and activate the surface of the glass substrate, which is conducive to enhancing the bonding between the anti-reflection film and the substrate.

[0008] (2) Preparation of composite sol: Tetraethyl silicate, anhydrous ethanol, F127 (poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol)), hydrochloric acid, boric acid, and deionized water are used as raw materials. After stirring and mixing and aging, a composite sol is obtained and set aside.

[0009] (3) Preparation of anti-reflection coating solution: Tetraethyl silicate and methyltriethoxysilane are added to the composite sol prepared in step (2) in sequence, and after stirring, mixing and aging, a high-efficiency anti-reflection coating solution is obtained; the composite sol of step (2) is introduced into a double silicon source together with step (3), and boric acid is introduced at the same time, so that after the reaction, a disordered stacking of SiO2 particles of two different sizes is generated, so as to form a thin film with a special pore structure in the subsequent steps.

[0010] (4) Preparation of anti-reflection and anti-reflection film: The high-efficiency anti-reflection and anti-reflection coating solution prepared in step (3) is coated on the glass substrate pretreated in step (1) by the immersion and pulling method. After standing and high-temperature tempering treatment, the above-mentioned high-efficiency anti-reflection and anti-reflection film is formed on the photovoltaic glass substrate.

[0011] Furthermore, in the above step (1), the specific steps of pretreatment of photovoltaic glass are: first, rinse the surface of photovoltaic glass with deionized water; then soak the photovoltaic glass in a hydrochloric acid solution with a concentration of 0.3-0.5 mol / L for 10-12 minutes, take it out and continue to rinse with deionized water; then use deionized water and anhydrous ethanol to ultrasonically clean the photovoltaic glass for 7-10 minutes in sequence; finally, place the cleaned photovoltaic glass in a vacuum drying oven at 80°C for drying.

[0012] Furthermore, in the above step (2), the ratio of the composite sol is: in parts by mass, tetraethyl silicate (C8H 20 O4Si): 23-28, anhydrous ethanol: 54-58, F127: 3.6-7.2 parts, hydrochloric acid: 0.3-0.4, boric acid: 0.9-3, deionized water: 8.7-9.5; the stirring and mixing refers to: carrying out in a magnetic stirrer at a stirring speed of 500-600 r / min and a stirring time of 1-1.5 hours; the aging refers to: sealing the mixed solution and standing at room temperature for 7 days.

[0013] Furthermore, in the above step (2), the mass percentage concentration of tetraethyl silicate used is 99%, the mass fraction of hydrochloric acid is 37%, and the mass percentage concentration of anhydrous ethanol is ≥99.7%. The molecular weight of F127 is 15,000.

[0014] Furthermore, in the above step (3), the preparation process of the anti-reflection coating solution is as follows: 90.8 parts by mass of the composite sol are taken, tetraethyl silicate (C8H 20 The composite sol is added with 6.9-11.5 parts of C7H18O4Si) and stirred evenly in a magnetic stirrer at a speed of 500-600 r / min for 1-1.5 hours. After standing and aging at room temperature for 2 days under sealed conditions, 2.3-2.8 parts of methyltriethoxysilane (C7H18O3Si) are added to the above mixture and stirred evenly in a magnetic stirrer at a speed of 500-600 r / min for 1-1.5 hours. The mixture is then stood and aged at room temperature for 3 days under sealed conditions to obtain a high-efficiency anti-reflection coating solution.

[0015] Furthermore, in the above step (4), the dipping and pulling is carried out in a dipping and pulling machine, the dipping speed is 3000-4000 μm / s, the dipping time is 10-12 s, the pulling speed is 500-600 μm / s, and the environmental conditions are: temperature 20-30°C, relative humidity 40% to 60%.

[0016] Furthermore, in the above step (4), the specific process of the standing and high-temperature tempering treatment is: standing in the atmosphere for 20-30 minutes; tempering is carried out in a muffle furnace at a tempering temperature of 730-740°C and a tempering time of 90-120 seconds to obtain the above-mentioned high-efficiency anti-reflection and anti-transmission film.

[0017] Secondly, the present application provides a high-efficiency anti-reflection and anti-reflection film obtained by the above method.

[0018] In the technical solution of the present application, boric acid is added during the preparation of the composite sol in step (2), and another silicon source is added during the preparation of the anti-reflection and anti-reflection coating solution in step (3), thereby making the cross-linked network structure within the sol in the anti-reflection and anti-reflection coating solution more compact and increasing the tendency of particle agglomeration. Large particles generated by partial particle agglomeration coexist with small particles that have not agglomerated within the system, resulting in the prepared film having a lower transmittance gain for light with a near-infrared wavelength (780-1100nm).

[0019] The advantages and beneficial effects of the present invention are:

[0020] (1) The anti-reflection film prepared on the surface of photovoltaic glass by this method has a low transmittance near the near-infrared short-wave band and a high transmittance in other bands, thereby improving the utilization rate of solar energy.

[0021] (2) The raw materials used in the present invention are easy to obtain, inexpensive, safe and non-toxic.

[0022] (3) The preparation steps of the present invention are simple, convenient and easy to implement, and have no special requirements for production equipment, which is conducive to industrial promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is an SEM image of the high-efficiency anti-reflection and anti-reflection film for photovoltaic glass prepared in Example 1.

[0024] Figure 2 This is the transmittance curve of the high-efficiency anti-reflection and anti-reflection film for photovoltaic glass prepared in Example 1. DETAILED DESCRIPTION

[0025] The following examples use 99% tetraethyl silicate (actual mass in the examples, the same below), 99.7% anhydrous ethanol, 15,000 F127 molecular weight, 98% methyltriethoxysilane, and 99% boric acid solid powder, all purchased from Shanghai Aladdin Reagent Co., Ltd. Hydrochloric acid, 37% by mass, was purchased from Nanjing Chemical Reagent Co., Ltd. K9 photovoltaic glass was purchased from Changchun Aopu Optoelectronics Technology Co., Ltd.

[0026] The stirring device used in the following examples is a heat-collecting magnetic stirrer (DF-101S) produced by Shanghai Lichen Bangxi Instrument Technology Co., Ltd., the immersion coating machine (SC-DP-1) is produced by Beijing Saidekaisi Electronics Co., Ltd., and the muffle furnace (SX-6-17) is produced by Shanghai Caixing High Temperature Component Electric Furnace Factory.

[0027] The transmittance of the anti-reflection film prepared in the following examples was tested using a BTG-8 photovoltaic glass spectral transmittance tester produced by Qinhuangdao Xianhe Technology Co., Ltd. in accordance with GB / T2410-2024, and the test wavelength range was 380-1100nm. The hardness of the anti-reflection film was tested using a QHQ-A portable pencil scratch tester produced by Aripus Corporation in accordance with GB / T6739-2022.

[0028] The present invention is described in detail below through specific examples, but the use and purpose of these exemplary embodiments are only used to illustrate the present invention, and do not constitute any form of limitation on the actual protection scope of the present invention, nor limit the protection scope of the present invention to them.

[0029] Example 1

[0030] 1. Pretreatment of photovoltaic glass: K9 photovoltaic glass was selected as the substrate. The surface of the photovoltaic glass was first rinsed with deionized water. The photovoltaic glass was then immersed in a diluted hydrochloric acid solution with a concentration of 0.3 mol / L for 10 minutes. After removal, it was rinsed with deionized water. The substrate was then ultrasonically cleaned with deionized water and anhydrous ethanol for 7 minutes. Finally, the cleaned photovoltaic glass was dried in a vacuum drying oven at 80°C for 15 minutes.

[0031] 2. Preparation of a composite sol: Tetraethyl silicate, anhydrous ethanol, F127, hydrochloric acid, boric acid, and deionized water were used as raw materials. The composite sol composition (by weight) was: 23 parts tetraethyl silicate, 54 parts anhydrous ethanol, 3.6 parts F127, 0.3 parts hydrochloric acid, 0.9 parts boric acid, and 8.7 parts deionized water. The mixture was stirred in a magnetic stirrer at 500 rpm for 1 hour. The mixture was then sealed and allowed to stand at room temperature for 7 days to obtain a composite sol.

[0032] 3. Preparation of anti-reflection and anti-reflection coating solution: Take 90.8 parts of the composite sol prepared in step 2, add 6.9 parts of tetraethyl silicate to the composite sol, and stir in a magnetic stirrer at a stirring speed of 500 r / min for 1 hour; seal the mixed solution, let it stand at room temperature, and age for 2 days; then add 2.3 parts of methyltriethoxysilane to the above mixed solution, stir in a magnetic stirrer at a stirring speed of 500 r / min for 1 hour; then seal the mixed solution, let it stand at room temperature, and age for 3 days to obtain a high-efficiency anti-reflection and anti-reflection coating solution for photovoltaic glass.

[0033] 4. Preparation of anti-reflection and anti-reflection film: The environmental conditions for preparing the coating are as follows: at a temperature of 20°C and a relative humidity of 40%, first place the pretreated photovoltaic glass and the high-efficiency anti-reflection and anti-reflection coating solution prepared in step (3) in an immersion and pulling machine at a dipping speed of 3000 μm / s and a dipping time of 10 s; then pull the glass at a pulling speed of 500 μm / s; then let it stand in the air for 20 minutes; then place it in a muffle furnace preheated to 730°C and temper it for 120 seconds to obtain a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass.

[0034] The SEM image of the high-efficiency anti-reflection film for photovoltaic glass prepared in this embodiment is as follows: Figure 1As shown, the prepared film (coating) is primarily composed of granular silica, with some large particles formed by agglomeration of small silica particles also visible. Testing showed that the high-efficiency antireflection and antireflection film prepared in this example had a transmittance of 94.34% over the full wavelength range of 380-1100 nm, including 95.46% in the visible light range and 93.64% in the near-infrared wavelength range (780-1100 nm). The film had a hardness of 3H.

[0035] Figure 2 This is the transmittance curve of the high-efficiency anti-reflection and anti-transmittance film for photovoltaic glass prepared in this embodiment. It can be seen that the film (coating) prepared in this embodiment has the characteristics of high transmittance gain in the visible light band and low transmittance gain in the near-infrared short-wave band (obvious pits appear in the curve).

[0036] Example 2

[0037] 1. Pretreatment of photovoltaic glass: K9 photovoltaic glass was selected as the substrate. The surface of the photovoltaic glass was first rinsed with deionized water. The photovoltaic glass was then immersed in a diluted hydrochloric acid solution with a concentration of 0.4 mol / L for 11 minutes. After removal, it was rinsed with deionized water. The substrate was then ultrasonically cleaned with deionized water and anhydrous ethanol for 8 minutes. Finally, the cleaned photovoltaic glass was dried in a vacuum drying oven at 80°C.

[0038] 2. Preparation of a Composite Sol: Tetraethyl silicate, anhydrous ethanol, F127, hydrochloric acid, boric acid, and deionized water were used as raw materials. The composite sol composition (by weight) was: 25 parts tetraethyl silicate, 56 parts anhydrous ethanol, 5.0 parts F127, 0.4 parts hydrochloric acid, 2.0 parts boric acid, and 9.2 parts deionized water. The mixture was stirred in a magnetic stirrer at 550 rpm for 1.5 hours. The mixture was then sealed and allowed to stand at room temperature for 7 days.

[0039] 3. Preparation of anti-reflection and anti-reflection coating solution: take 90.8 parts of composite sol, add 8.5 parts of tetraethyl silicate to the composite sol, stir in a magnetic stirrer at a speed of 550 r / min, and the stirring time is 1.5 hours; seal the mixed solution, let it stand at room temperature, and age for 2 days; then add 2.5 parts of methyltriethoxysilane to the above mixed solution, stir in a magnetic stirrer at a speed of 550 r / min, and the stirring time is 1.5 hours; then seal the mixed solution, let it stand at room temperature, and age for 3 days to obtain a high-efficiency anti-reflection and anti-reflection coating solution for photovoltaic glass.

[0040] 4. Preparation of anti-reflection and anti-reflection film: The environmental conditions for preparing the coating are as follows: at a temperature of 25°C and a relative humidity of 50%, first place the pretreated photovoltaic glass and the high-efficiency anti-reflection and anti-reflection coating solution prepared in step (3) in an immersion and pulling machine at a dipping speed of 3500 μm / s and a dipping time of 12 seconds; then pull the film at a pulling speed of 550 μm / s; then let it stand in the air for 25 minutes; then place it in a muffle furnace at 740°C and temper it for 90 seconds to obtain a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass.

[0041] After testing, the high-efficiency anti-reflection and anti-reflection film prepared in this embodiment has a transmittance of 94.77% in the wavelength range of 380-1100nm, a transmittance of 95.61% in the visible light range, and a transmittance of 93.58% in the near-infrared wavelength range (780-1100nm). The hardness of the film is 3H.

[0042] Example 3

[0043] 1. Pretreatment of photovoltaic glass: K9 photovoltaic glass was selected as the substrate. The surface of the photovoltaic glass was first rinsed with deionized water. The photovoltaic glass was then immersed in a diluted hydrochloric acid solution with a concentration of 0.5 mol / L for 12 minutes. After being taken out, it was rinsed with deionized water. The substrate was then ultrasonically cleaned with deionized water and anhydrous ethanol for 10 minutes. Finally, the cleaned photovoltaic glass was dried in a vacuum drying oven at 80°C.

[0044] 2. Preparation of Composite Sol: Tetraethyl silicate, anhydrous ethanol, F127, hydrochloric acid, boric acid, and deionized water were used as raw materials. The composite sol composition by weight was: 28 parts tetraethyl silicate, 58 parts anhydrous ethanol, 7.2 parts F127, 0.35 parts hydrochloric acid, 3.0 parts boric acid, and 9.5 parts deionized water. The mixture was stirred in a magnetic stirrer at 600 rpm for 1.2 hours. The mixture was then sealed and allowed to stand at room temperature for 7 days.

[0045] 3. Preparation of anti-reflection and anti-reflection coating solution: take 90.8 parts of composite sol, add 11.5 parts of tetraethyl silicate to the composite sol, stir in a magnetic stirrer, stirring speed, 600 r / min, stirring time is 1.3 hours; seal the mixed solution, let it stand at room temperature, and age for 2 days; then add 2.8 parts of methyltriethoxysilane to the above mixed solution, stir in a magnetic stirrer, stirring speed, 600 r / min, stirring time is 1.3 hours; then seal the mixed solution, let it stand at room temperature, and age for 3 days to obtain a high-efficiency anti-reflection and anti-reflection coating solution for photovoltaic glass.

[0046] 4. Preparation of anti-reflection and anti-reflection film: The environmental conditions for preparing the coating are as follows: at a temperature of 30°C and a relative humidity of 60%, first place the pretreated photovoltaic glass and the high-efficiency anti-reflection and anti-reflection coating solution prepared in step (3) in an immersion and pulling machine with an immersion speed of 4000 μm / s and an immersion time of 11 seconds; then pull the film with a pulling speed of 600 μm / s; then let it stand in the air for 30 minutes; then place it in a muffle furnace at 735°C for tempering for 100 seconds to obtain a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass.

[0047] After testing, the high-efficiency anti-reflection and anti-reflection film prepared in this embodiment has a transmittance of 94.18% in the wavelength range of 380-1100nm, a transmittance of 95.23% in the visible light range, and a transmittance of 93.61% in the near-infrared wavelength range (780-1100nm). The hardness of the film is 3H.

[0048] The above embodiments are only used to illustrate the contents of the present invention rather than to limit the present invention. Therefore, any changes within the meaning and scope equivalent to the claims of the present invention should be considered to be included in the scope of the claims.

[0049] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass, characterized in that: The specific steps are as follows: 1) Clean and dry the photovoltaic glass and use it as a glass substrate for future use; 2) Tetraethyl silicate, anhydrous ethanol, F127 (poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol)), hydrochloric acid, boric acid, and deionized water are mixed and aged to obtain a composite sol for later use; In the composite sol, by mass, tetraethyl silicate: 23-28 parts, anhydrous ethanol: 54-58 parts, F127 (poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol)): 3.6-7.2 parts, hydrochloric acid: 0.3-0.4 parts, boric acid: 0.9-3 parts, deionized water: 8.7-9.5 parts; 3) adding tetraethyl silicate and methyltriethoxysilane to the composite sol, and aging to obtain a coating solution; the amounts of the composite sol, tetraethyl silicate, and methyltriethoxysilane added are 90.8 parts by mass, 6.9-11.5 parts by mass, and 2.3-2.8 parts by mass, respectively; 4) The coating solution is applied to the surface of the glass substrate obtained in step 1), and after standing and high-temperature tempering treatment, the high-efficiency anti-reflection and anti-transmission film is formed on the surface of the photovoltaic glass substrate.

2. The method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass according to claim 1, characterized in that: Step 1) The cleaning comprises: first rinsing the photovoltaic glass with deionized water, then soaking it in a hydrochloric acid solution, then rinsing it again with deionized water, and finally ultrasonically cleaning the photovoltaic glass with deionized water and anhydrous ethanol in sequence.

3. The method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass according to claim 1, characterized in that: Step 2) The mixing refers to stirring and mixing for 1-1.5 hours; and the aging refers to standing and aging at room temperature under sealed conditions for 7 days.

4. The method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass according to claim 1, characterized in that: Step 3) adding tetraethyl silicate and methyltriethoxysilane to the composite sol means adding tetraethyl silicate to the composite sol and stirring for 1-1.5 hours; then allowing to stand and age at room temperature for 2 days under sealed conditions to obtain a mixed solution; then adding methyltriethoxysilane to the mixed solution and stirring for 1-1.5 hours; then allowing to stand and age at room temperature for 3 days under sealed conditions to obtain a coating solution.

5. The method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass according to claim 1, characterized in that: Step 4) The coating is to coat the coating solution on the surface of the glass substrate by using a dipping and pulling method, with an immersion speed of 3000-4000 μm / s, an immersion time of 10-12 s, and a pulling speed of 500-600 μm / s.

6. The method for preparing a high-efficiency anti-reflection and anti-reflection film for photovoltaic glass according to claim 1, characterized in that: Step 4) The static and high-temperature tempering treatment refers to standing for 20-30 minutes and then tempering at 730-740° C. for 90-120 seconds.

7. A high-efficiency anti-reflection and anti-transmission film for photovoltaic glass prepared by the method according to any one of claims 1 to 6.

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