Antistatic self-cleaning coating for photovoltaic glass and preparation method thereof

Abstract

The invention belongs to the technical field of coatings for photovoltaic glass, and particularly relates to an antistatic self-cleaning coating for photovoltaic glass and a preparation method thereof.The antistatic self-cleaning coating comprises a component A, a component B and a component C according to the mass ratio of 1: 1: 0.1-1: 2: 0.4; wherein the component A is prepared from the following raw materials in parts by mass: 60 to 80 parts of methyltrialkoxysilane, not more than 10 parts of tetraalkoxysilane, not more than 10 parts of gamma-(2, 3-epoxypropoxy) propyltrimethoxysilane, not more than 10 parts of hexamethyldisilazane, not more than 10 parts of hexadecyl trialkoxysilane and 0.5 to 3 parts of a catalyst; the component B is prepared from the following raw materials in parts by mass: 20 to 30 parts of ATO solution, 60 to 75 parts of silica sol and 1.5 to 5.5 parts of functional additive; the component C is prepared from the following raw materials in parts by mass: 70 to 80 parts of trimethyl alkoxy silane and 20 to 30 parts of trimethyl silanol.

Description

Technical Field

[0001] The present invention belongs to the technical field of coatings for photovoltaic glass, and particularly relates to a coating for antistatic self-cleaning photovoltaic glass and a preparation method thereof. Background Art

[0002] With the continuous exploration and development of solar energy by people, photovoltaic modules have emerged. In order to improve the power generation efficiency, photovoltaic glass must be highly transparent so that sufficient sunlight can pass through. However, during long-term outdoor use, the dust accumulated on the surface of photovoltaic glass adheres to the surface of photovoltaic glass mainly through van der Waals force, capillary force and electrostatic attraction, reducing the transmittance of sunlight and seriously affecting the power generation efficiency of photovoltaic modules.

[0003] It is reported that for photovoltaic panels not cleaned within a month, the output power will be lost by 5% - 33% due to dust accumulation. In the United States, the annual power generation of photovoltaic cells is reduced by 7% under the influence of natural dust deposition; the power generation efficiency of photovoltaic power stations in the desert area of Qinghai Province, China, can be reduced by 5% - 25% under the influence of dust deposition. Therefore, keeping the photovoltaic glass panel clean is the key to ensuring the output power of solar cells.

[0004] Existing photovoltaic panel cleaning technologies (such as machine cleaning or high-pressure water flushing technology) consume extremely high amounts of water and require a large amount of electricity; if relying solely on natural rainwater for cleaning, problems such as incomplete cleaning, sewage stains and water scale on the glass surface will occur. In such a case, coating a layer of dust-proof or self-cleaning coating on the surface of photovoltaic glass to reduce the impact of dust accumulation on the transmittance and output power of photovoltaic panels is a more economical option.

[0005] However, photovoltaic modules are applications in complex outdoor scenarios. For example, in hot and dry seasons or regions, static electricity will be generated on the surface of the glass after friction with dry air, which is extremely easy to adsorb dust in the air. At the same time, the glass cover plate covering the solar cells will also be affected by the electric potential generated by the bottom cells. Generally, the voltage generated by a single piece of solar cell is above 20V, and the output voltage of a large-scale battery module can reach above 100V; if many modules are arranged in series, the output voltage under light irradiation will even reach 1000 - 1500V. The electrostatic potential generated by the voltage will generate a long-range attraction to dust, and the action range reaches within 1mm on the glass surface, which is much larger than the action range of van der Waals force.

[0006] Therefore, existing self-cleaning coatings for photovoltaic glass can only be applied in seasons with sufficient rainwater, and manual cleaning is still required in the dry season. How to overcome the defect of insufficient self-cleaning effect of photovoltaic glass in an environment with insufficient rainwater is a technical problem urgently to be solved in this field.

[0007] It should be noted that the above information disclosed in this background art section is only for understanding the background art of the concept of this application. Therefore, the above description is not considered as information of the prior art. Summary of the Invention

[0008] The embodiments of the present disclosure at least provide a coating for antistatic self-cleaning photovoltaic glass and a preparation method thereof.

[0009] In a first aspect, the embodiments of the present disclosure provide a coating for antistatic self-cleaning photovoltaic glass, including the following components: Component A, Component B, and Component C, and the mass ratio satisfies 1:1:0.1 to 1:2:0.4; wherein, Component A includes the following raw materials in parts by mass: 60 - 80 parts of methyltrialkoxysilane, no more than 10 parts of tetraalkoxysilane, no more than 10 parts of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, no more than 10 parts of hexamethyldisilazane, no more than 10 parts of hexadecyltrialkoxysilane, and 0.5 - 3 parts of catalyst; Component B includes the following raw materials in parts by mass: 20 - 30 parts of ATO solution, 60 - 75 parts of silica sol, and 1.5 - 5.5 parts of functional additives; Component C includes the following raw materials in parts by mass: 70 - 80 parts of trimethylalkoxysilane and 20 - 30 parts of trimethylsilanol.

[0010] In an optional embodiment, the ATO solution includes the following components in parts by mass: 20 - 30 parts of stannous chloride dihydrate, 50 - 60 parts of ethanol, and 10 - 30 parts of antimony trichloride.

[0011] In an optional embodiment, in Component A, the methyltrialkoxysilane includes at least one of methyltrimethoxysilane and methyltriethoxysilane; the tetraalkoxysilane includes at least one of tetramethoxysilane and tetraethoxysilane; the hexadecyltrialkoxysilane includes at least one of hexadecyltrimethoxysilane and hexadecyltriethoxysilane; the catalyst is a mixed solution of any one or more of formic acid, acetic acid, and citric acid.

[0012] In an optional embodiment, in Component B, the pH value of the silica sol is 4 - 6, and the particle size is 5 - 50 nm.

[0013] In an optional embodiment, in Component B, the functional additives include a defoaming agent, a wetting and leveling agent, and an anti-sagging agent.

[0014] In an optional embodiment, in Component C, the trimethylalkoxysilane is trimethylmethoxysilane or trimethylethoxysilane.

[0015] Second aspect, the embodiments of the present disclosure further provide a preparation method of the antistatic self-cleaning photovoltaic glass coating as described above, including the following steps: methyltrialkoxysilane, tetraalkoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, hexamethyldisilazane, cetyltrialkoxysilane and a catalyst are stirred and mixed at room temperature to obtain component A; an ATO solution, silica sol and a functional auxiliary agent are stirred and mixed at room temperature to obtain component B; trimethylalkoxysilane and trimethylsilanol are stirred and mixed at room temperature to obtain component C; the photovoltaic glass substrate is immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for surface hydroxyl modification and then washed and dried to obtain a pretreated substrate; at room temperature, component A and component B are first mixed and stirred for reaction, then component C is added and stirred for reaction, and filtered to obtain the antistatic self-cleaning photovoltaic glass coating.

[0016] In an optional embodiment, the preparation method of the ATO solution is: stannous chloride dihydrate is dissolved in ethanol, stirred at room temperature, and then antimony trichloride is added, and stirred in a water bath not higher than 60 °C, and the liquid obtained after cooling is the ATO solution; the preparation method of component B is specifically: the ATO solution, defoamer, wetting and leveling agent, and anti-sagging agent are added dropwise to acidic silica sol, and stirred and dispersed in a water bath not higher than 40 °C, and the liquid obtained after cooling is component B.

[0017] In an optional embodiment, the stirring speed of the mixing and stirring of component A and component B is 500-800 r / min, and the stirring duration is 20-30 min; the reaction duration of adding component C and stirring for reaction is 20-30 min; the curing temperature is 150-170 °C, and the curing duration is 10-20 min.

[0018] Third aspect, the embodiments of the present disclosure further provide a preparation method of an antistatic self-cleaning photovoltaic glass coating, using the antistatic self-cleaning photovoltaic glass coating as described above or the antistatic self-cleaning photovoltaic glass coating prepared by the method as described above, roll-coated on the surface of the substrate, and dried and cured to obtain the antistatic self-cleaning photovoltaic glass coating.

[0019] The beneficial effects of the present invention are as follows. The antistatic self-cleaning coating for photovoltaic glass and its preparation method introduce superhydrophobic hexamethyldisilazane and cetyltrialkoxysilane, and are capped with trimethylalkoxysilane to further improve the hydrophobic durability of the coating. The static WCA of the prepared coating reaches 160°. The hydrophobic coating with low hydroxyl groups and low surface energy reduces the dust adsorption due to van der Waals forces, and also reduces the adsorption of hydrogen bonds and chemical bonds between dust and the hydroxyl groups on the coating surface. The coating is not easy to form a water film or droplets, reducing the capillary force adsorption of dust. At the same time, a wide-bandgap transparent semiconductor material, antimony-doped tin oxide (ATO), is introduced, greatly reducing the long-range attraction of the electrostatic potential generated by the photovoltaic module to dust. In addition, the -Si-O-Si- structure coating has good weather resistance and high hardness, and has more extensive application value in dry seasons and regions such as deserts.

[0020] Other features and advantages of the present invention will be described in the following specification, and in part will be obvious from the specification, or will be understood by implementing the present invention. The objects and other advantages of the present invention are achieved and obtained by the structures specifically pointed out in the specification.

[0021] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following specific preferred embodiments are given for detailed description as follows. Detailed Embodiments

[0022] To make the objects, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0023] As used herein, phrases such as "in one embodiment", "according to one embodiment", "in some embodiments", etc. generally refer to the fact that the specific features, structures, or characteristics after the phrase can be included in at least one embodiment of the present disclosure. Therefore, a specific feature, structure, or characteristic can be included in more than one embodiment of the present disclosure, such that these phrases do not necessarily refer to the same embodiment. As used herein, terms such as "example", "exemplary", etc. are used "as an example, instance, or illustration. Any embodiment, aspect, or design described herein as "example" or "exemplary" is not necessarily construed as being preferred or superior to other embodiments, aspects, or designs. Instead, the use of terms such as "example", "exemplary", etc. is intended to present concepts in a specific manner.

[0024] In this document, as used herein, expressions such as "at least one of..." modify the entire list of elements when following a list of elements, rather than modifying individual elements in the list. For example, the expression "at least one of a, b, and c" should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0025] The terms used herein are for the purpose of describing particular exemplary configurations only and are not intended to be limiting. As used herein, the singular articles "a", "an", and "the" may also be intended to include the plural forms, unless the context clearly indicates otherwise. The terms "comprising", "including", and "having" are inclusive and thus specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein should not be construed as necessarily requiring them to be performed in the particular order discussed or illustrated, unless specifically identified as an order of performance. Additional or alternative steps may be employed.

[0026] ITO has good conductivity, but is scarce in resources and high in cost. The ATO conductive layer has balanced conductivity, transparency, and stability, and high cost performance, and is an ideal alternative material for ITO.

[0027] ATO nanoparticles are prone to agglomeration, so directly setting an ATO coating on photovoltaic glass does not have an ideal effect. Compared with directly adding ATO, in the present invention, by grafting and modifying silica sol, its dispersibility is improved, and at the same time, it undergoes hydrolysis and condensation with organosilicon monomers to form a chemical bond with a dense -Si-O-Si- inorganic network structure, forming a denser interpenetrating network structure. The coating has both conductivity and superhydrophobicity, realizes the integration of multiple functions, and further reduces the physical and chemical adsorption of the coating to dust.

[0028] Regarding the defects existing in the above - mentioned solutions, they are all the results obtained by the inventors after practice and careful research. Therefore, the process of discovering the above - mentioned problems and the solutions proposed by the present disclosure for the above - mentioned problems in the following text should both be contributions made by the inventors to the present disclosure during the process of the present disclosure.

[0029] Some embodiments of the present invention will be described in detail below. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0030] The present disclosure embodiments provide a coating for antistatic self-cleaning photovoltaic glass, which includes the following components: Component A, Component B, and Component C, and the mass ratio satisfies 1:1:0.1 to 1:2:0.4; wherein, Component A includes the following raw materials in parts by mass: 60 to 80 parts of methyltrialkoxysilane, no more than 10 parts of tetraalkoxysilane, no more than 10 parts of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, no more than 10 parts of hexamethyldisilazane, no more than 10 parts of hexadecyltrialkoxysilane, and 0.5 to 3 parts of a catalyst; Component B includes the following raw materials in parts by mass: 20 to 30 parts of an ATO solution, 60 to 75 parts of silica sol, and 1.5 to 5.5 parts of a functional additive; Component C includes the following raw materials in parts by mass: 70 to 80 parts of trimethylalkoxysilane and 20 to 30 parts of trimethylsilanol.

[0031] In some embodiments, specifically, the ATO solution includes the following components in parts by mass: 20 to 30 parts of stannous chloride dihydrate, 50 to 60 parts of ethanol, and 10 to 30 parts of antimony trichloride.

[0032] In some embodiments, specifically, in Component A, the methyltrialkoxysilane includes at least one of methyltrimethoxysilane and methyltriethoxysilane; the tetraalkoxysilane includes at least one of tetramethoxysilane and tetraethoxysilane; the hexadecyltrialkoxysilane includes at least one of hexadecyltrimethoxysilane and hexadecyltriethoxysilane; the catalyst is a mixed solution of any one or more of formic acid, acetic acid, and citric acid.

[0033] In some embodiments, specifically, in Component B, the pH value of the silica sol is 4 to 6, and the particle size is 5 to 50 nm.

[0034] In some embodiments, specifically, in Component B, the functional additive includes an antifoaming agent, a wetting and leveling agent, and an anti-sagging agent.

[0035] In some embodiments, specifically, in Component C, the trimethylalkoxysilane is trimethylmethoxysilane or trimethyltriethoxysilane.

[0036] The embodiments of the present disclosure also provide a preparation method of the antistatic self-cleaning photovoltaic glass coating as described above, including the following steps: mixing methyltrialkoxysilane, tetraalkoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, hexamethyldisilazane, cetyltrialkoxysilane and a catalyst at room temperature with stirring to obtain component A; mixing an ATO solution, silica sol and a functional additive at room temperature with stirring to obtain component B; mixing trimethylalkoxysilane and trimethylsilanol at room temperature with stirring to obtain component C; soaking a photovoltaic glass substrate in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for surface hydroxyl modification, and then cleaning and drying to obtain a pretreated substrate; at room temperature, mixing and stirring components A and B first for reaction, then adding component C for stirring reaction, and filtering to obtain the antistatic self-cleaning photovoltaic glass coating.

[0037] In some embodiments, specifically, the preparation method of the ATO solution is as follows: dissolving stannous chloride dihydrate in ethanol, stirring at room temperature, adding antimony trichloride, and stirring in a water bath not higher than 60°C, and the liquid obtained after cooling is the ATO solution; the preparation method of component B is specifically as follows: dropping the ATO solution, defoamer, wetting and leveling agent, and anti-sagging agent into acidic silica sol, and stirring and dispersing in a water bath not higher than 40°C, and the liquid obtained after cooling is component B.

[0038] In some embodiments, specifically, the stirring speed of mixing and stirring components A and B is 500 - 800 r / min, and the stirring duration is 20 - 30 min; the reaction duration of adding component C for stirring reaction is 20 - 30 min; the curing temperature is 150 - 170°C, and the curing duration is 10 - 20 min.

[0039] The embodiments of the present disclosure also provide a preparation method of an antistatic self-cleaning photovoltaic glass coating, using the antistatic self-cleaning photovoltaic glass coating as described above or the antistatic self-cleaning photovoltaic glass coating prepared by the method as described above, roll-coating it on the surface of the substrate, and drying and curing to obtain the antistatic self-cleaning photovoltaic glass coating.

[0040] In the following examples, the self-made modified silica sol is prepared by modifying the acidic silica sol HS-4-30 (with a pH value of 4.5, a solid content of 30 wt%, and a silica sol particle size of 10 nm) produced by Zhejiang Yuda Chemical Co., Ltd., and it can also be modified using silica sol produced by Jinan Quanxin Chemical Co., Ltd. or Guangdong Huierte Nano Technology Co., Ltd.

[0041] In the examples, the defoamer is BYK-024 of BYK company, the wetting and leveling agent is BYK-3480 of BYK company, and the anti-sagging agent is RHEOBYK-7600 of BYK company.

[0042] The methods for detecting the coating properties are as follows: The hardness is determined according to the method of GB / T 6739-2006; the adhesion is determined according to the method of GB / T 9286-1998; the light transmittance is determined according to the method of GB / T 2410-2008; the hydrophobic angle is determined according to the method of GB / T 24368-2009; the antistatic property is tested by a surface resistance meter at multiple points and the average value is taken; the high and low temperature shock: impact is carried out at -20°C to 40°C for 10 cycles; the aging resistance is accelerated by artificial climate aging for 500 h (the loss of gloss rate ≤ 10%, △E ≤ 1.5); the dust-proof property is simulated outdoors with flour: the flour is spread on the glass with the coating, the glass is placed vertically at 90°, and the falling situation of the flour is observed.

[0043] Example 1

[0044] Preparation of ATO solution: Dissolve 20 parts by mass of stannous chloride dihydrate in 55 parts by mass of ethanol, stir at room temperature for 1 h, then add 25 parts by mass of antimony trichloride, and stir in a water bath at 60°C for 4 h. The liquid obtained after cooling is the antimony-doped tin oxide (ATO) solution.

[0045] Preparation of ATO-modified silica sol: Drop 25 parts by mass of ATO solution, 3 parts by mass of wetting and leveling agent, 1 part by mass of defoaming agent and 1 part by mass of anti-sagging agent into 70 parts by mass of silica sol and stir. Stir and disperse in a water bath at 40°C for 2 h. The liquid obtained after cooling, filtering and packaging is the ATO-modified silica sol.

[0046] Example 2

[0047] Preparation of ATO solution: Dissolve 25 parts by mass of stannous chloride dihydrate in 55 parts by mass of ethanol, stir at room temperature for 1 h, then add 20 parts by mass of antimony trichloride, and stir in a water bath at 60°C for 4 h. The liquid obtained after cooling is the antimony-doped tin oxide (ATO) solution.

[0048] Preparation of ATO-modified silica sol: Drop 20 parts by mass of ATO solution, 3 parts by mass of wetting and leveling agent, 1 part by mass of defoaming agent and 1 part by mass of anti-sagging agent into 75 parts by mass of silica sol and stir. Stir and disperse in a water bath at 40°C for 2 h. The liquid obtained after cooling, filtering and packaging is the ATO-modified silica sol.

[0049] Example 3

[0050] Preparation of ATO solution: Dissolve 30 parts by mass of stannous chloride dihydrate in 50 parts by mass of ethanol, stir at room temperature for 1 h, then add 20 parts by mass of antimony trichloride, and stir in a water bath at 60°C for 4 h. The liquid obtained after cooling is the antimony-doped tin oxide (ATO) solution.

[0051] Preparation of ATO-modified silica sol: 30 parts by mass of ATO solution, 3 parts by mass of wetting and leveling agent, 1 part by mass of defoaming agent and 1 part by mass of anti-sagging agent were dropped into 65 parts by mass of silica sol and stirred. Stirring and dispersing were carried out in a water bath at 40 °C for 2 h, and after cooling, filtration and packaging were carried out, and the obtained liquid was ATO-modified silica sol.

[0052] Example 4

[0053] Preparation of Component A: 80 parts by mass of methyltrimethoxysilane of commercially available analytical pure grade, 5 parts by mass of tetramethoxysilane, 5 parts by mass of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 5 parts by mass of hexamethyldisilazane, 3 parts by mass of cetyltrialkoxysilane, and 2 parts by mass of acetic acid were successively added to a stirring barrel and stirred evenly to obtain Component A.

[0054] Preparation of Component B: The ATO-modified silica sol prepared in Example 1 was Component B.

[0055] Preparation of Component C: 80 parts by mass of trimethylmethoxysilane of commercially available analytical pure grade and 20 parts by mass of trimethylsilanol were added to a stirring barrel and stirred evenly to obtain Component C.

[0056] Preparation of the coating: Components A, B, and C were formulated into a paint in a ratio of 1:1:0.1. First, Components A and B were mixed and stirred and reacted at 500 - 800 r / min for 20 - 30 min, and then Component C was added and mixed and reacted for 20 - 30 min. Filtration was carried out through a 300-mesh filter screen to obtain the coating for photovoltaic glass.

[0057] Preparation of the coating: The photovoltaic glass substrate was immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 7:3) for surface hydroxyl modification and then washed and dried. It was roll-coated onto the substrate surface, the film thickness was controlled at about 10 μm, and it was cured at 170 °C for 20 min to obtain the photovoltaic glass coating.

[0058] Example 5

[0059] Preparation of Component A: 70 parts by mass of methyltrimethoxysilane of commercially available analytical pure grade, 4 parts by mass of tetramethoxysilane, 4 parts by mass of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 10 parts by mass of hexamethyldisilazane, 10 parts by mass of cetyltrialkoxysilane, and 2 parts by mass of acetic acid were successively added to a stirring barrel and stirred evenly to obtain Component A.

[0060] Preparation of Component B: The ATO-modified silica sol prepared in Example 2 was Component B.

[0061] Preparation of Component C: 75 parts by mass of trimethylmethoxysilane of commercially available analytical pure grade and 25 parts by mass of trimethylsilanol were added to a stirring barrel and stirred evenly to obtain Component C.

[0062] Preparation of the coating: Components A, B, and C are mixed to prepare the paint in a ratio of 1:1.5:0.2. First, mix Component A and Component B, and then stir and react at 500 - 800 r / min for 20 - 30 min. Next, add Component C and mix and react for 20 - 30 min. Filter through a 300-mesh sieve to obtain the coating for photovoltaic glass.

[0063] Preparation of the coating: Immerse the photovoltaic glass substrate in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 7:3) for surface hydroxyl modification, then wash and dry. Roll-coat it onto the substrate surface, control the film thickness at about 10 μm, and cure at 170 °C for 20 min to obtain the photovoltaic glass coating.

[0064] Example 6

[0065] Preparation of Component A: Add 65 parts by mass of commercially available analytical pure methyltrimethoxysilane, 7 parts by mass of tetramethoxysilane, 8 parts by mass of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 8 parts by mass of hexamethyldisilazane, 10 parts by mass of cetyltrialkoxysilane, and 2 parts by mass of acetic acid to a stirring tank in sequence and stir evenly to obtain Component A.

[0066] Preparation of Component B: The ATO-modified silica sol prepared in Example 3 is Component B.

[0067] Preparation of Component C: Add 70 parts by mass of commercially available analytical pure trimethylmethoxysilane and 30 parts by mass of trimethylsilanol to a stirring tank and stir evenly to obtain Component C.

[0068] Preparation of the coating: Components A, B, and C are mixed to prepare the paint in a ratio of 1:2:0.4. First, mix Component A and Component B, and then stir and react at 500 - 800 r / min for 20 - 30 min. Next, add Component C and mix and react for 20 - 30 min. Filter through a 300-mesh sieve to obtain the coating for photovoltaic glass.

[0069] Preparation of the coating: Immerse the photovoltaic glass substrate in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 7:3) for surface hydroxyl modification, then wash and dry. Roll-coat it onto the substrate surface, control the film thickness at about 10 μm, and cure at 170 °C for 20 min to obtain the photovoltaic glass coating.

[0070] Example 7

[0071] Preparation of Component A: Add 73 parts by mass of commercially available analytical pure methyltrimethoxysilane, 7 parts by mass of tetramethoxysilane, 7 parts by mass of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, 8 parts by mass of hexamethyldisilazane, 8 parts by mass of cetyltrialkoxysilane, and 2 parts by mass of acetic acid to a stirring tank in sequence and stir evenly to obtain Component A.

[0072] Preparation of Component B: 3 parts by mass of a wetting and leveling agent, 1 part by mass of an antifoaming agent, and 1 part by mass of an anti-sagging agent were added dropwise to 95 parts by mass of acidic silica sol and stirred evenly to obtain Component B.

[0073] Preparation of Component C: 78 parts by mass of trimethylmethoxysilane and 22 parts by mass of trimethylsilanol of commercially available analytical pure grade were added to a stirring tank and stirred evenly to obtain Component C.

[0074] Preparation of the coating: Components A, B, and C were mixed for paint preparation in a ratio of 1:1.5:0.3. First, Component A and Component B were mixed and stirred and reacted at 500 - 800 r / min for 20 - 30 min, then Component C was added and mixed and reacted for 20 - 30 min. After filtration through a 300-mesh sieve, the coating for photovoltaic glass was obtained.

[0075] Preparation of the coating: The photovoltaic glass substrate was immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 7:3) for surface hydroxyl modification and then washed and dried. It was roll-coated onto the substrate surface, controlling the film thickness at about 10 μm, and cured at 170 °C for 20 min to obtain the photovoltaic glass coating.

[0076] The coatings prepared in each example were subjected to relevant performance tests, and the data were summarized in Table 1.

[0077] Table 1 Performance data of the coatings prepared in each example

[0078]

[0079] As can be seen from Table 1 above, for the superhydrophobic monomer and subsequent hydroxyl capping treatment, the less hydroxyl groups remaining on the coating surface, the more significantly the hydrophobicity of the coating can be improved. Thus, the durability of the coating can also be ensured. The more the ATO content, the better the antistatic effect of the coating, but the coating will be significantly foggy, affecting the light transmittance. By comprehensively balancing the light transmittance, hydrophobicity, and antistatic effect of the coating, the photovoltaic glass coating is required to have a self-cleaning function in seasons or regions with sufficient rain, and at the same time be antistatic in dry seasons or regions, reducing the electrostatic potential on the glass surface and the electrostatic attraction to dust deposition. In addition, the coating of the present invention also has high hardness, resistance to temperature difference changes, and good weather resistance, showing great application potential in outdoor anti-fouling and easy cleaning of photovoltaic power generation components.

[0080] In summary, the coating for antistatic self-cleaning photovoltaic glass and its preparation method introduce superhydrophobic hexamethyldisilazane and cetyltrialkoxysilane, and are capped with trimethylalkoxysilane to further improve the hydrophobic durability of the coating. The static WCA of the prepared coating reaches 160°. The hydrophobic coating with low hydroxyl and low surface energy reduces the dust adsorption by van der Waals force and also reduces the adsorption of hydrogen bonds and chemical bonds between dust and surface hydroxyl groups of the coating. The coating is not easy to form water films and droplets, reducing the capillary force adsorption of dust. At the same time, the introduction of the wide-bandgap transparent semiconductor material antimony-doped tin oxide (ATO) greatly reduces the long-range attraction of electrostatic potential generated by photovoltaic modules to dust. In addition, the -Si-O-Si- structure coating has good weather resistance and high hardness, and has more extensive application value in dry seasons and regions such as deserts.

[0081] Enlightened by the above ideal embodiments according to the present invention, through the above description, relevant staff can make various changes and modifications completely within the scope of not deviating from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An antistatic self-cleaning coating for photovoltaic glass, characterized in that, It includes the following components: Component A, Component B and Component C, and the mass ratio satisfies 1:1:0.1 - 1:2:0.4; Among them, Component A includes the following raw materials in parts by mass: 60 - 80 parts of methyltrialkoxysilane, no more than 10 parts of tetraalkoxysilane, no more than 10 parts of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, no more than 10 parts of hexamethyldisilazane, no more than 10 parts of cetyltrialkoxysilane, and 0.5 - 3 parts of catalyst; Component B includes the following raw materials in parts by mass: 20 - 30 parts of ATO solution, 60 - 75 parts of silica sol, and 1.5 - 5.5 parts of functional auxiliary; Component C includes the following raw materials in parts by mass: 70 - 80 parts of trimethylalkoxysilane and 20 - 30 parts of trimethylsilanol.

2. The coating for antistatic self-cleaning photovoltaic glass according to claim 1, wherein the ATO solution includes the following components in parts by mass: 20 - 30 parts of stannous chloride dihydrate, 50 - 60 parts of ethanol, and 10 - 30 parts of antimony trichloride.

3. The coating for antistatic self-cleaning photovoltaic glass according to claim 1, wherein in Component A, the methyltrialkoxysilane includes at least one of methyltrimethoxysilane and methyltriethoxysilane; the tetraalkoxysilane includes at least one of tetramethoxysilane and tetraethoxysilane; the cetyltrialkoxysilane includes at least one of cetyltrimethoxysilane and cetyltriethoxysilane; the catalyst is a mixed solution of any one or more of formic acid, acetic acid, and citric acid.

4. The coating for antistatic self-cleaning photovoltaic glass according to claim 1, wherein in Component B, the pH value of the silica sol is 4 - 6, and the particle size is 5 - 50 nm.

5. The coating for antistatic self-cleaning photovoltaic glass according to claim 1, wherein in Component B, the functional auxiliary includes a defoamer, a wetting and leveling agent, and an anti-sagging agent.

6. The coating for antistatic self-cleaning photovoltaic glass according to claim 1, wherein in Component C, the trimethylalkoxysilane is trimethylmethoxysilane or trimethylethoxysilane.

7. A method for preparing a coating for antistatic and self-cleaning photovoltaic glass according to any one of claims 1-6, characterized in that, It includes the following steps: After mixing methyltrialkoxysilane, tetraalkoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, hexamethyldisilazane, cetyltrialkoxysilane and catalyst by stirring at room temperature, Component A is prepared; After mixing ATO solution, silica sol and functional auxiliary by stirring at room temperature, Component B is prepared; After mixing trimethylalkoxysilane and trimethylsilanol by stirring at room temperature, Component C is prepared; The photovoltaic glass substrate is immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide for surface hydroxyl modification, and then washed and dried to obtain a pretreated substrate; At room temperature, Component A and Component B are first mixed and stirred for reaction, and then Component C is added for stirring reaction and filtration to obtain the coating for antistatic self-cleaning photovoltaic glass.

8. The preparation method according to claim 7, wherein the preparation method of the ATO solution is: Dissolve stannous chloride dihydrate in ethanol, stir at room temperature, then add antimony trichloride, and stir in a water bath not higher than 60 °C. The liquid obtained after cooling is the ATO solution; The specific preparation method of the B component is as follows: Drop the ATO solution, defoamer, wetting and leveling agent, and anti-sagging agent into acidic silica sol, stir and disperse in a water bath not higher than 40 °C, and the liquid obtained after cooling is the B component.

9. The preparation method according to claim 7, wherein The stirring speed of mixing and stirring the A component and the B component is 500 - 800 r / min, and the stirring duration is 20 - 30 min; The reaction duration of adding the C component and stirring for reaction is 20 - 30 min; The curing temperature is 150 - 170 °C, and the curing duration is 10 - 20 min.

10. A preparation method of a coating for antistatic self-cleaning photovoltaic glass, characterized in that Use the coating for antistatic self-cleaning photovoltaic glass described in any one of claims 1 - 6 or the coating for antistatic self-cleaning photovoltaic glass prepared by the method described in any one of claims 7 - 9, roll coat it onto the surface of the substrate, and obtain the coating for antistatic self-cleaning photovoltaic glass after drying and curing.

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