Anti-PID self-cleaning nano coating glass, preparation method thereof and solar cell

Abstract

The invention belongs to the field of solar cells, and discloses anti-PID self-cleaning nano coating glass, a preparation method thereof and a solar cell. The anti-PID self-cleaning nano coating glass comprises a glass substrate and an anti-PID self-cleaning nano coating positioned on the glass substrate, wherein the anti-PID self-cleaning nano coating comprises a SiO2 network and a polyanion organic compound, wherein the SiO2 network is formed by crosslinking first nano SiO2 and second nano SiO2. The main chain of the polyanion organic compound contained in the coated glass has many negative charges and has a strong hydration group, the porous SiO2 network is beneficial to improving the antireflection performance and the mechanical performance, and the solar cell assembled by the coated glass has PID resistance and self-cleaning capacity.

Description

Technical Field

[0001] The present invention belongs to the field of solar cells, and particularly relates to an anti-PID self-cleaning nano-coated glass, a preparation method thereof, and a solar cell. Background Art

[0002] The Chinese full name of the PID effect (Potential Induced Degradation) is the potential induced degradation effect. Currently, there are two main types of PID effects: PID-s (leakage type) and PID-p (polarization type). The main reason for the PID effect is that after water vapor enters the component, EVA (ethylene-vinyl acetate copolymer) undergoes hydrolysis to produce acetate ions, and the acetate ions react with the alkali in the glass to produce free Na + , Na + Under the action of the electric field, it migrates to the battery surface or enters the battery interior, causing the battery to be inverted or the PN junction to penetrate, resulting in a significant attenuation of the component power. Currently, on the market, POE (polyolefin elastomer) film is mainly used to replace EVA film, and the excellent anti-aging performance of POE is used to reduce acetate ions from the film end, thereby reducing the concentration of Na + to achieve the effect of inhibiting PID. However, the POE film has low polarity and poor adhesion to the glass or backplane, and it is easy to have string offset during lamination in the component manufacturing process. At the same time, the compatibility between the POE resin and the polar additives is poor, making it easy for the polar additives to precipitate during subsequent processing and use.

[0003] Most solar photovoltaic power station bases are built in suburban areas, and the surface of photovoltaic glass is prone to dust accumulation. The deposition of dust will significantly reduce the power generation efficiency and affect the heat dissipation capacity of the components, and may cause the photovoltaic panel to burn under extreme conditions. To continuously keep the surface of the photovoltaic panel clean, it needs to be manually cleaned during the maintenance of the photovoltaic power station, which is costly. Moreover, existing manual conventional cleaning, robot cleaning, high-pressure water cleaning and other methods will cause rapid damage to the surface anti-transmittance coating of the solar photovoltaic power generation panel, resulting in a faster attenuation of the transmittance.

[0004] Currently, on the market, the anti-PID performance of components is mainly improved by improving the film. By replacing with POE without acidic groups, or by adding additives (such as titanium dioxide) to reduce the precipitation of free acetate ions in EVA. These have inhibited the PID effect of the components to a certain extent. However, the change in the film formula will cause unpredictable defects in the component manufacturing process and requires a long manufacturing running-in period. The hydrophilicity of titanium dioxide mainly stems from the internal defects in its anatase TiO2. After the defects absorb photons below 387.5 nm, the electrons in the valence band are excited to the conduction band, forming highly active electrons e - , and positively charged holes h + , and the electrons combine with Ti 4+react, and the holes react with the oxygen ions on the surface to form Ti 3+ and oxygen vacancies. Subsequently, the water in the air dissociates and adsorbs on the oxygen vacancies to form chemically adsorbed hydroxyl groups. These hydroxyl groups have strong oxidizing and strong hydration abilities, which are beneficial for decomposing most organic substances and forming a water film. However, the above-mentioned defects of titanium dioxide will gradually disappear under long-term light excitation, and finally the hydrophilicity and photocatalytic effect will be lost. SUMMARY OF THE INVENTION

[0005] In view of the above problems existing in the prior art, the present invention provides an anti-PID self-cleaning nano-coated glass and its preparation method and application.

[0006] Specifically, one aspect of the present invention provides an anti-PID self-cleaning nano-coated glass, which comprises a glass substrate and an anti-PID self-cleaning nano-coating located on the glass substrate. The anti-PID self-cleaning nano-coating comprises a SiO2 network crosslinked by first nano-SiO2 and second nano-SiO2 and a polyanionic organic compound. Among them, the particle size of the first nano-SiO2 is 20-80 nm, and the particle size of the second nano-SiO2 is 100-120 nm.

[0007] In one or more embodiments, the first nano-SiO2 is derived from SiO2 wet sol.

[0008] In one or more embodiments, the polyanionic organic compound is selected from polymers of sulfonates.

[0009] In one or more embodiments, the polyanionic organic compound is selected from one or both of sodium polyvinyl sulfonate and sodium polystyrene sulfonate.

[0010] In one or more embodiments, the thickness of the anti-PID self-cleaning nano-coating is 120-140 nm.

[0011] Another aspect of the present invention provides a method for preparing an anti-PID self-cleaning nano-coating, the method comprising the following steps:

[0012] S1: Mix tetraethyl orthosilicate, water, and ethanol uniformly, and adjust the pH of the solution to 3-5 with acid to obtain a SiO2 wet sol containing first nano-SiO2, and set aside;

[0013] S2: Add second nano-SiO2 and a dispersant to the SiO2 wet sol prepared in step S1, and stir until the liquid becomes clear to obtain a SiO2 dispersion, and set aside;

[0014] S3: Add a coupling agent, ethanol, water, and a polyanionic organic compound to the SiO2 dispersion obtained in step S2, and stir until the liquid becomes clear to obtain a glass coating for standby;

[0015] S4: Coat the glass coating obtained in step S3 and heat for curing to obtain the anti-PID self-cleaning nano-coating.

[0016] In one or more embodiments, in step S1, the ethyl silicate is tetraethyl orthosilicate, and the acid is hydrochloric acid, acetic acid, or phosphoric acid.

[0017] In one or more embodiments, in step S1, the mass ratio of ethyl silicate to water is 1:3 - 4:11, and the mass ratio of ethyl silicate to ethanol is 3:4 - 4:3.

[0018] In one or more embodiments, in step S2, the dispersant is selected from the structure of formula I: In formula I, R1, R2, R3, and R4 are each independently selected from methyl, methoxy, or halogen, and R1, R2, R3, and R4 are not simultaneously methyl, methoxy, or halogen.

[0019] In one or more embodiments, in step S2, the dispersant is selected from one or more of trimethylmethoxysilane, dimethyldichlorosilane, and trimethoxymethylsilane.

[0020] In one or more embodiments, in step S1, the mass ratio of the ethyl silicate to the second nanoparticles in step S2 is 1:1 - 2:1, and the mass ratio of the ethyl silicate in step S1 to the dispersant in step S2 is 3:2 - 4:1.

[0021] In one or more embodiments, in step S3, the coupling agent is selected from one or more of amino-silane coupling agents and epoxy-silane coupling agents; the amino-silane coupling agents include KH540 and KH550, and the epoxy-silane coupling agent includes KH560.

[0022] In one or more embodiments, in step S3, the mass ratio of the SiO2 dispersion obtained in step S2 to the coupling agent in step S3 is 8:3 - 6:1, the mass ratio of the SiO2 dispersion obtained in step S2 to the ethanol in step S3 is 8:25 - 3:5, the mass ratio of the SiO2 dispersion obtained in step S2 to the water in step S3 is 8:75 - 12:65, and the mass ratio of the SiO2 dispersion obtained in step S2 to the polyanionic organic compound in step S3 is 4:1 - 12:1.

[0023] In one or more embodiments, in step S4, the coating method is roll coating.

[0024] In one or more embodiments, in step S4, the temperature for heat curing is 170°C - 185°C.

[0025] In one or more embodiments, in step S4, the time for heat curing is 1 - 2 minutes.

[0026] Another aspect of the present invention also provides an anti-PID self-cleaning nano-coating prepared by the method of any one of the embodiments herein.

[0027] Another aspect of the present invention also provides an anti-PID self-cleaning nano-coated glass, and the anti-PID self-cleaning nano-coated glass comprises a glass substrate and the anti-PID self-cleaning nano-coating described in any one of the embodiments herein located on the glass substrate.

[0028] Another aspect of the present invention also provides a solar cell, and the solar cell includes the anti-PID self-cleaning nano-coated glass prepared by any one of the embodiments herein. Description of the Drawings

[0029] Figure 1 It is a schematic diagram of the preparation method of the anti-PID self-cleaning nano-coated glass in some embodiments of the present invention. Detailed Embodiments

[0030] To enable those skilled in the art to understand the features and effects of the present invention, the following provides a general description and definition of the terms and phrases mentioned herein. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art for the present invention. When there are conflicting situations, the definition in this specification shall prevail.

[0031] The theories or mechanisms described and disclosed herein, whether correct or not, shall not limit the scope of the present invention in any way, that is, the content of the present invention can be implemented without being limited by any specific theory or mechanism.

[0032] In this article, terms such as "comprising", "including", "containing" and similar terms cover the meanings of "consisting essentially of" and "consisting of". For example, when it is disclosed herein that "A comprises B and C", it should be considered that "A consists essentially of B and C" and "A consists of B and C" have been disclosed herein.

[0033] In this article, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents and concentrations, are only for the sake of brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be regarded as having covered and specifically disclosed all possible sub-ranges and individual numerical values within the range (including integers and fractions).

[0034] In this text, unless otherwise specified, percentages refer to mass percentages and ratios refer to mass ratios.

[0035] In this text, when describing embodiments or examples, it should be understood that they are not used to limit the present invention to these embodiments or examples. On the contrary, all alternatives, improvements, and equivalents of the methods and materials described in the present invention can be covered within the scope defined by the present invention.

[0036] In this text, for the sake of brevity of description, all possible combinations of all technical features in each embodiment or example are not described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered as being within the scope described in this specification.

[0037] The preparation method of the anti-PID self-cleaning nano-coated glass of the present invention comprises the following steps:

[0038] S1: Mix 15-20 parts by mass of tetraethyl orthosilicate, 55-60 parts by mass of water, and 15-20 parts by mass of ethanol uniformly, and adjust the pH of the solution to 3-5 with an acid to obtain a wet SiO2 sol for standby;

[0039] S2: Add 10-15 parts by mass of nano-SiO2 and 5-10 parts by mass of a dispersant to the wet SiO2 sol prepared in step S1, and stir until the liquid becomes transparent and clear to obtain a SiO2 dispersion for standby;

[0040] S3: Take 8-12 parts by mass of the SiO2 dispersion prepared in step S2, add 2-3 parts by mass of a coupling agent, 20-25 parts by mass of ethanol, 65-75 parts by mass of water, and 1-2 parts by mass of a polyanionic organic compound to the SiO2 dispersion, and stir until the liquid becomes transparent and clear to obtain a glass coating for standby;

[0041] S4: Coat the glass coating obtained in step S3 on the surface of a glass substrate, and heat and cure it at 170°C - 185°C for 1-2 minutes to obtain the anti-PID self-cleaning nano-coated glass.

[0042] In the present invention, the water is preferably deionized water.

[0043] In step S1 of the present invention, the mass fraction of the tetraethyl orthosilicate used is preferably 15-20 parts by mass, such as 16 parts by mass, 17 parts by mass, 18 parts by mass, 19 parts by mass. Controlling the amount of tetraethyl orthosilicate within the foregoing range is beneficial to improving the anti-PID and self-cleaning capabilities of the solar cell module assembled with the anti-PID self-cleaning nano-coated glass, and is also beneficial to improving the mechanical strength and light transmittance of the coating.

[0044] In step S1 of the present invention, the mass fraction of ethanol used is preferably 15-20 parts by mass, such as 16 parts by mass, 17 parts by mass, 18 parts by mass, 19 parts by mass. The acid used is 1-2 parts by mass. Controlling the amount of ethanol within the aforementioned range is beneficial to improving the PID resistance and self-cleaning ability of the solar cell module assembled with the anti-PID self-cleaning nano-coated glass, and is also beneficial to improving the mechanical strength and light transmittance of the coating.

[0045] In step S1 of the present invention, the final pH of the SiO2 wet sol solution is 3-5, such as pH = 3, pH = 4, pH = 5. Controlling the pH of the SiO2 wet sol solution within the aforementioned range is beneficial to improving the PID resistance and self-cleaning ability of the solar cell module assembled with the anti-PID self-cleaning nano-coated glass, and is also beneficial to improving the mechanical strength and light transmittance of the coating. The acid used to adjust the pH of the solution can be hydrochloric acid solution, acetic acid solution or phosphoric acid solution, and the mass fraction of the hydrochloric acid solution, acetic acid solution or phosphoric acid solution used is preferably 5%.

[0046] In step S1 of the present invention, the prepared SiO2 wet sol is in a chain structure, and the particle size of the SiO2 wet sol is 100-120 nm, such as 101 nm, 102 nm, 103 nm, 104 nm, 105 nm, 106 nm, 107 nm, 108 nm, 109 nm, 110 nm, 111 nm, 112 nm, 113 nm, 114 nm, 115 nm, 116 nm, 117 nm, 118 nm, 119 nm. Controlling the particle size of the SiO2 wet sol within the aforementioned range is beneficial to improving the PID resistance and self-cleaning ability of the solar cell module assembled with the anti-PID self-cleaning nano-coated glass, and is also beneficial to improving the mechanical strength and light transmittance of the coating.

[0047] In step S2 of the present invention, the mass fraction of nano-SiO2 used is 10-15 parts by mass, such as 11 parts by mass, 12 parts by mass, 13 parts by mass, 14 parts by mass. Controlling the amount of nano-SiO2 within the aforementioned range is beneficial to improving the PID resistance and self-cleaning ability of the solar cell module assembled with the anti-PID self-cleaning nano-coated glass, and is also beneficial to improving the mechanical strength and light transmittance of the coating.

[0048] In step S2 of the present invention, the particle size of the nano-SiO2 used is 20-80 nm, such as 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm.

[0049] The inventors of the present invention unexpectedly found that in step S2, nano-SiO2 with a particle size of 20 - 80 nm during the wet state of film solution curing and crosslinking crosslinked with SiO2 particles with a size of 100 - 120 nm in the SiO2 wet sol to form a dense SiO2 film with tiny pores. This dense SiO2 film has excellent antireflection and antireflective properties and mechanical properties. When the particle size of the nano-SiO2 is too large, a dense SiO2 film cannot be formed, resulting in a significant decrease in the hardness of the coating. When the particle size of the nano-SiO2 is too small, the mechanical properties of the film layer will be significantly improved, but it will lead to a decrease in the porosity of the film layer and a decrease in the antireflection and antireflective properties of the film layer.

[0050] In step S2 of the present invention, the dispersant can modify the hydroxyl groups on the surface of SiO2, reduce the agglomeration of nano-SiO2, make it uniformly distributed in the film solution, and improve the light transmittance of the film layer.

[0051] In step S2 of the present invention, the mass fraction of the dispersant used is 5 - 10 parts by mass, such as 6 parts by mass, 7 parts by mass, 8 parts by mass, 9 parts by mass.

[0052] In step S3 of the present invention, the SiO2 dispersion liquid used is 8 - 12 parts by mass, such as 9 parts by mass, 10 parts by mass, 11 parts by mass.

[0053] In step S3 of the present invention, the coupling agent can graft the hydroxyl groups that are not fully modified in step S2, further improving the uniformity of SiO2 in the film solution.

[0054] In step S3 of the present invention, the coupling agent used is 2 - 3 parts by mass.

[0055] In step S3 of the present invention, the ethanol used is 20 - 25 parts by mass, such as 21 parts by mass, 22 parts by mass, 23 parts by mass, 24 parts by mass.

[0056] In step S3 of the present invention, the polyanionic organic compound is one or a combination of two of sodium polyvinyl sulfonate and sodium polystyrene sulfonate containing sulfonic acid root polar groups. Its sulfonic acid root groups have strong hydration ability, which can make the film layer show superhydrophilicity and carry negative charges. Through electrostatic adsorption, it can effectively weaken the tendency of free sodium and calcium ions in the glass to migrate to the surface of the battery chip, achieving the effect of anti-PID.

[0057] In step S3 of the present invention, the polyanionic organic compound used is preferably 1 - 2 parts by mass. Controlling the dosage of the polyanionic organic compound within the aforementioned range is beneficial to improving the anti-PID and self-cleaning capabilities of the solar cell module assembled with the anti-PID self-cleaning nano-coated glass, and is also beneficial to improving the mechanical strength and light transmittance of the coating.

[0058] In step S4 of the present invention, the glass coating is applied by roll coating at a roll coating speed of 4 - 10 m / min, such as 5 m / min, 6 m / min, 7 m / min, 8 m / min, 9 m / min.

[0059] In step S4 of the present invention, the heat curing temperature is 170°C - 185°C, such as 171°C, 172°C, 173°C, 174°C, 175°C, 176°C, 177°C, 178°C, 179°C, 180°C, 181°C, 182°C, 183°C, 184°C.

[0060] In step S4 of the present invention, the heat curing time is 1 - 2 min, such as 1 min 10 s, 1 min 20 s, 1 min 30 s, 1 min 40 s, 1 min 50 s, 1 min 60 s.

[0061] In some embodiments, as Figure 1 shown, the method for preparing the anti-PID self-cleaning nano-coating of the present invention includes:

[0062] S1: Mix 55 - 60 parts by mass of deionized water, 15 - 20 parts by mass of tetraethyl orthosilicate, and 15 - 20 parts by mass of ethanol in a reaction kettle, add 1 - 2 parts by mass of acid while stirring, and adjust the pH of the solution to 3 - 5 to obtain a SiO2 wet sol.

[0063] S2: In the reaction kettle, add 10 - 15 parts by mass of nano-SiO2 and 8 parts by mass of trimethyldichlorosilane to the SiO2 wet sol prepared in step S1, and stir until the liquid is transparent and clear to obtain a SiO2 dispersion.

[0064] S3: Take 8 - 12 parts by mass of the SiO2 dispersion prepared in step S2, and sequentially add 2 - 3 parts by mass of a coupling agent, 20 - 25 parts by mass of ethanol, 65 - 75 parts by mass of deionized water, and 1 - 2 parts by mass of a polyanionic organic compound thereto, mix evenly, and stir until the liquid is transparent and clear to obtain a glass coating.

[0065] S4: Coat the glass coating obtained in step S3 on the glass surface, preferably by roll coating, and then heat cure at 170 - 185°C for 1 - 2 min to obtain the anti-PID self-cleaning nano-coated glass.

[0066] In the present invention, the thickness of the anti-PID self-cleaning nano-coating is preferably 120-140 nm, such as 121 nm, 122 nm, 123 nm, 124 nm, 125 nm, 126 nm, 127 nm, 128 nm, 129 nm, 130 nm, 131 nm, 132 nm, 133 nm, 134 nm, 135 nm, 136 nm, 137 nm, 138 nm, 139 nm, and more preferably 123-127 nm. Controlling the coating thickness within the aforementioned range is beneficial to improving the anti-PID and self-cleaning capabilities of the solar cell module assembled with the anti-PID self-cleaning nano-coated glass, and is also beneficial to improving the mechanical strength and light transmittance of the coating. When the coating thickness is too large, the glass transmittance decreases, resulting in power attenuation of the solar cell module. When the coating thickness is too small, the role of the coating in improving the anti-PID and self-cleaning capabilities of the module cannot be effectively exerted.

[0067] Another aspect of the present invention provides a solar cell module, which includes the anti-PID self-cleaning nano-coated glass described in any of the embodiments herein.

[0068] In one or more embodiments, the solar cell module includes one or more of the following devices: a PN junction device containing III-V or II-IV group elements, a Cu-In-Ga-Se thin film device, an organic sensitizer device, an organic thin film device, a quantum dot thin film device, an amorphous silicon solar cell, a microcrystalline silicon solar cell, and a crystalline silicon solar device.

[0069] Another aspect of the present invention provides a method for enhancing the anti-PID performance of a solar cell, which includes introducing the anti-PID self-cleaning nano-coated glass described in any of the embodiments herein into the solar cell.

[0070] In one or more embodiments, the solar cell includes one or more of the following devices: a PN junction device containing III-V or II-IV group elements, a Cu-In-Ga-Se thin film device, an organic sensitizer device, an organic thin film device, a quantum dot thin film device, an amorphous silicon solar cell device, a microcrystalline silicon solar cell device, and a crystalline silicon solar device.

[0071] In the present invention, an antireflection film composed of nano-silica and anionic polyelectrolyte is coated on the glass surface. The present invention has the following beneficial technical effects: Since the anionic polyelectrolyte has many negative charges on its main chain, it can electrostatically adsorb sodium and calcium ions in the front glass, weakening Na +The migration trend towards SiNx / EVA reduces the positive charge density at the SiNx / EVA and SiNx / Si interfaces, effectively improving the component's resistance to PID-s and PID-p. At the same time, the polar functional groups of the anionic polyelectrolyte, such as the sulfonic acid groups of sodium polystyrene sulfonate, have strong hydration ability and exhibit strong hydrophilicity, ensuring that the WCA on the component surface can reach below 10°. It is oleophobic and hydrophilic. When it rains or condenses, a water film forms on the entire surface of the hydrophilic coating and flows down under the action of gravity. At the same time, because its affinity for water is much stronger than that for dirt, water will automatically seep under the dirt, float the dirt up, and flow down with the water, achieving a self-cleaning effect. Under the washing of natural rainwater, the glass surface can be efficiently cleaned. In addition, this solution only coats a layer of film solution on the glass surface, has no impact on the component manufacturing process, and can quickly enter mass production.

[0072] The present invention will be described below by way of specific embodiments. It should be understood that these embodiments are illustrative only and are not intended to limit the scope of the present invention. The methods, reagents, and materials used in the embodiments are conventional methods, reagents, and materials in the art unless otherwise specified. The compounds in the embodiments can all be purchased through commercial channels.

[0073] In the present invention, the particle size of SiO2 is measured by scanning electron microscopy (SEM).

[0074] Example 1

[0075] This example prepares an anti-PID self-cleaning nano-coated glass and a solar cell module through the following steps:

[0076] S1: In a reaction kettle, 50 parts by mass of deionized water, 15 parts by mass of tetraethyl orthosilicate, and 15 parts by mass of ethanol are mixed. While stirring, 2 parts by mass of a 5% hydrochloric acid solution is added, and the pH of the solution is adjusted to 4 to obtain a SiO2 wet sol with an average particle size of 100 nm.

[0077] S2: In the reaction kettle, 10 parts by mass of nano-SiO2 with an average particle size of 20 nm and 8 parts by mass of trimethyldichlorosilane are added to the SiO2 wet sol. After mixing, it is stirred until the liquid is transparent and clear to obtain a SiO2 dispersion.

[0078] S3: Take 8 parts by mass of the SiO2 dispersion, and sequentially add 2 parts by mass of KH540 coupling agent, 20 parts by mass of ethanol, 68 parts by mass of deionized water, and 2 parts by mass of sodium polystyrene sulfonate (Mw: 70000; Sigma-Aldrich, China). Mix well and stir until the liquid is transparent and clear to obtain a glass coating.

[0079] S4: Set the axis speed of the roller to 6 m / min, coat the above-mentioned glass coating on the glass surface by roll coating, and after baking at 185 °C for 1.5 min, obtain a coated glass with a film thickness of about 125 nm;

[0080] S5: Prepare a solar cell module. Use the coated glass, 430 g EPE of Saiwu, 410 g EPE of Saiwu, TOPCON cell, Yubang tin-copper solder tape, bus bar, and 2.0 mm enameled back glass of Follett prepared in this example to prepare the module. The specific operation method is as follows: Use the solder tape for series welding to form a cell string, then use the bus bar for overlapping welding to form a cell string group, and then stack them in the order of back glass, 410 g EPE, cell string group, 430 g EPE, and the coated glass of this example, heat, evacuate, laminate, and hold pressure in a laminator, take out and cool and frame.

[0081] Example 2

[0082] Prepare the glass coating, coated glass and solar cell module of Example 2 by a method similar to that of Example 1, but the difference is that: replace the nano-SiO₂ with an average particle size of 20 nm used in step S2 with nano-SiO₂ with an equal mass fraction and an average particle size of 50 nm.

[0083] Example 3

[0084] Prepare the glass coating, coated glass and solar cell module of Example 3 by a method similar to that of Example 1, but the difference is that: replace the nano-SiO₂ with an average particle size of 20 nm used in step S2 with nano-SiO₂ with an equal mass fraction and an average particle size of 80 nm.

[0085] Example 4

[0086] Prepare the glass coating, coated glass and solar cell module of Example 4 by a method similar to that of Example 1, but the difference is that: during roll coating in step S4, the axis speed of the roller used is 5 m / min, and the thickness of the glass film layer obtained after roll coating and baking is about 140 nm.

[0087] Example 5

[0088] Prepare the glass coating, coated glass and solar cell module of Example 3 by a method similar to that of Example 1, but the difference is that: the pH of the solution in step S1 is 3, and SiO₂ wet sol with an average particle size of 120 nm is obtained.

[0089] Comparative Example 1

[0090] Prepare a solar cell module according to step S5 of Example 1 using ordinary photovoltaic coated glass (Follett double-layer coated embossed glass).

[0091] Comparative Example 2

[0092] The glass coating, coated glass, and solar cell module of Comparative Example 2 were prepared by a method similar to that of Example 1, except that: no dispersant was added in step S2.

[0093] Comparative Example 3

[0094] The glass coating, coated glass, and solar cell module of Comparative Example 3 were prepared by a method similar to that of Example 1, except that: no polyanionic organic compound was added in step S3.

[0095] Comparative Example 4

[0096] The glass coating, coated glass, and solar cell module of Comparative Example 4 were prepared by a method similar to that of Example 1, except that: the nano-SiO2 with an average particle size of 20 nm used in step S2 was replaced with nano-SiO2 with an average particle size of 100 nm in the same mass fraction.

[0097] Comparative Example 5

[0098] The glass coating, coated glass, and solar cell module of Comparative Example 5 were prepared by a method similar to that of Example 1, except that: during roll coating in step S4, the linear speed of the roll axis was 3 m / min, and the thickness of the glass film layer obtained after roll coating and baking was about 180 nm.

[0099] Test Example

[0100] The coated glass and solar cell modules prepared in the above Examples 1-5 and Comparative Examples 1-5 were tested for performance by the following test methods in the present invention:

[0101] The transmittance of the coated glass was measured using an OptoTest GST-3;

[0102] The water contact angle of each coated glass was recorded using a Drop Shape Analyzer DSA100;

[0103] The pencil hardness of each film layer was tested according to the standard of GB / T6739-2006;

[0104] The module was placed outdoors at an oblique angle of 35°, and its dust accumulation was observed for 3 months, recorded with "+", and the more the number, the more serious the dust accumulation;

[0105] The PID test of the solar cell module was carried out under the conditions of 85 °C, 85% RH, and -1000 V for 192 h, and its power attenuation was recorded.

[0106] The results of each test are shown in Table 1.

[0107] Table 1: Performance test results of Examples 1-5 and Comparative Examples 1-5

[0108]

[0109] As shown in Table 1, compared with Comparative Example 1, the light transmittance of Examples 1-5 is basically the same, indicating that the glass film layer of the present invention meets the basic requirements of existing photovoltaic modules for glass antireflection enhancement. In Examples 1-5, due to the addition of polyanionic organic compounds, the film layer contains strong hydrophilic groups, and the water contact angle is about 10.5°, showing strong hydrophilicity. Therefore, it performs well in the outdoor dust accumulation test for 3 months, significantly better than Comparative Example 1. Moreover, due to the presence of negatively charged sulfonate groups in the film layer, it performs well in the PID test, and the PID 192h power attenuation is about 2%, compared with the 4.89% power attenuation of ordinary coated glass modules, showing good anti-PID performance.

[0110] In Comparative Example 2, since no dispersant was added to the film solution in step S2, the nano-SiO2 agglomerated, resulting in an insufficiently dense glass film layer, a decrease in coating hardness, and a reduction in light transmittance.

[0111] In Comparative Example 3, since no polyanionic organic compound was added to the film solution in step S3, the water contact angle of its glass surface is similar to that of Comparative Example 1 and does not show hydrophilicity. Therefore, it accumulates a lot of dust in the outdoor dust accumulation test. And in the PID 192h test, the power attenuation of its component is 5.01%, which is equivalent to that of Comparative Example 1.

[0112] In Comparative Example 4, since the particle size of the nano-SiO2 added to the film solution in step S2 is 100nm, compared with Examples 1-5, its light transmittance and coating hardness have decreased significantly, indicating that the particle size of nano-SiO2 affects the quality of the film layer. When the particle size is too large, the antireflection and antireflection enhancement effects and mechanical properties of the film layer will decrease significantly. The nano-SiO2 added to the film solution in step S2 uses the 20-80nm disclosed in the present invention, which can effectively crosslink with the large-particle SiO2 in the SiO2 wet sol to form a dense SiO2 film with tiny pores, thereby obtaining better antireflection and antireflection enhancement performance and mechanical properties.

[0113] In Comparative Example 5, the film layer thickness is about 180nm. As can be seen from Table 1, compared with Examples 1-4, its light transmittance has decreased significantly, indicating that an overly thick film layer on the glass surface will affect the antireflection and antireflection enhancement performance of the film layer.

Claims

1. An anti-PID self-cleaning nano-coating, characterized in that, The anti-PID self-cleaning nano-coating comprises a SiO2 network crosslinked by first nano-SiO2 and second nano-SiO2 and a polyanionic organic compound, wherein the particle size of the first nano-SiO2 is 20-80 nm, and the particle size of the second nano-SiO2 is 100-120 nm.

2. The anti-PID self-cleaning nano-coating according to claim 1, wherein the first nano-SiO2 is derived from SiO2 wet sol; the polyanionic organic compound is selected from polymers of sulfonates, preferably one or both of sodium polyvinyl sulfonate and sodium polystyrene sulfonate; the thickness of the anti-PID self-cleaning nano-coating is 120-140 nm.

3. The preparation method of the anti-PID self-cleaning nano-coating according to claim 1 or 2, characterized in that, The method comprises the following steps: S1: Mix tetraethyl orthosilicate, water and ethanol uniformly, adjust the pH of the solution to 3-5 with an acid to obtain a SiO2 wet sol containing the first nano-SiO2, and set aside; S2: Add the second nano-SiO2 and a dispersant to the SiO2 wet sol prepared in step S1, and stir until the liquid becomes clear to obtain a SiO2 dispersion, and set aside; S3: Add a coupling agent, ethanol, water and a polyanionic organic compound to the SiO2 dispersion prepared in step S2, and stir until the liquid becomes clear to obtain a glass coating, and set aside; S4: Coating the glass coating obtained in step S3, and heating and curing to obtain the anti-PID self-cleaning nano-coating.

4. The preparation method according to claim 3, characterized in that, The preparation method has one or more of the following characteristics: In step S1, the tetraethyl orthosilicate is tetraethyl orthosilicate, and the acid is hydrochloric acid, acetic acid or phosphoric acid; In step S1, the mass ratio of tetraethyl orthosilicate to water is 1:3-4:11, and the mass ratio of tetraethyl orthosilicate to ethanol is 3:4-4:3; In step S2, the dispersant is selected from the structure of formula I: In formula I, R1, R2, R3, and R4 are each independently selected from methyl, methoxy, or halogen, and R1, R2, R3, and R4 are not simultaneously methyl, methoxy, or halogen. Preferably, the dispersant is selected from one or more of trimethylmethoxysilane, dimethyldichlorosilane, and trimethoxymethylsilane; In step S2, the mass ratio of the tetraethyl orthosilicate in step S1 to the second nano-particles in step S2 is 1:1-2:1, and the mass ratio of the tetraethyl orthosilicate in step S1 to the dispersant in step S2 is 3:2-4:1; In step S3, the coupling agent is selected from one or more of amino-silane coupling agents and epoxy-silane coupling agents. The amino-silane coupling agents include KH540 and KH550, and the epoxy-silane coupling agents include KH560; In step S3, the mass ratio of the SiO2 dispersion prepared in step S2 to the coupling agent in step S3 is 8:3-6:1, the mass ratio of the SiO2 dispersion prepared in step S2 to the ethanol in step S3 is 8:25-3:5, the mass ratio of the SiO2 dispersion prepared in step S2 to the water in step S3 is 8:75-12:65, and the mass ratio of the SiO2 dispersion prepared in step S2 to the polyanionic organic compound in step S3 is 4:1-12:1; In step S4, the coating method is roll coating; In step S4, the temperature of heating and curing is 170°C-185°C; In step S4, the time of heating and curing is 1-2 min.

5. The anti-PID self-cleaning nano-coating prepared by the preparation method according to claim 3 or 4.

6. An anti-PID self-cleaning nano-coated glass, characterized in that, The anti-PID self-cleaning nano-coated glass comprises a glass substrate and the anti-PID self-cleaning nano-coating as described in Claim 1, 2 or 5 on the glass substrate.

7. A solar cell comprising the anti-PID self-cleaning nano-coated glass as described in Claim 6.

8. A glass coating, characterized in that, The glass coating comprises first nano-SiO2, second nano-SiO2, a polyanionic organic compound and a solvent, wherein the particle size of the first nano-SiO2 is 20 - 80 nm and the particle size of the second nano-SiO2 is 100 - 120 nm.

9. The glass coating as described in Claim 8, characterized in that the first nano-SiO2 is derived from SiO2 wet sol; the polyanionic organic compound is selected from polymers of sulfonates, preferably one or both of sodium polyvinyl sulfonate and sodium polystyrene sulfonate; the solvent comprises water and ethanol; the glass coating further comprises a dispersant and a coupling agent.

10. The preparation method of the glass coating according to claim 8 or 9, characterized in that The method comprises the following steps: S1: Mix tetraethyl orthosilicate, water and ethanol uniformly, adjust the pH of the solution to 3 - 5 with an acid to obtain SiO2 wet sol containing first nano-SiO2, and set aside; S2: Add second nano-SiO2 and a dispersant to the SiO2 wet sol prepared in step S1, stir until the liquid becomes clear to obtain SiO2 dispersion, and set aside; S3: Add a coupling agent, ethanol, water and a polyanionic organic compound to the SiO2 dispersion prepared in step S2, stir until the liquid becomes clear to obtain a glass coating.

11. The preparation method according to claim 10, characterized in that, The preparation method has one or more of the following characteristics: In step S1, the tetraethyl orthosilicate is tetraethyl orthosilicate, and the acid is hydrochloric acid, acetic acid or phosphoric acid; In step S1, the mass ratio of tetraethyl orthosilicate to water is 1:3 - 4:11, and the mass ratio of tetraethyl orthosilicate to ethanol is 3:4 - 4:3; In step S2, the dispersant is selected from the structure of formula I: In formula I, R1, R2, R3, and R4 are each independently selected from methyl, methoxy, or halogen, and R1, R2, R3, and R4 are not simultaneously methyl, methoxy, or halogen. Preferably, the dispersant is selected from one or more of trimethylmethoxysilane, dimethyldichlorosilane, and trimethoxymethylsilane; In step S2, the mass ratio of tetraethyl orthosilicate in step S1 to the second nano-particles in step S2 is 1:1 - 2:1, and the mass ratio of tetraethyl orthosilicate in step S1 to the dispersant in step S2 is 3:2 - 4:1; In step S3, the coupling agent is selected from one or more of amino-silane coupling agents and epoxy-silane coupling agents. The amino-silane coupling agents include KH540 and KH550, and the epoxy-silane coupling agent includes KH560; In step S3, the mass ratio of the SiO2 dispersion prepared in step S2 to the coupling agent in step S3 is 8:3 - 6:1, the mass ratio of the SiO2 dispersion prepared in step S2 to the ethanol in step S3 is 8:25 - 3:5, the mass ratio of the SiO2 dispersion prepared in step S2 to the water in step S3 is 8:75 - 12:65, and the mass ratio of the SiO2 dispersion prepared in step S2 to the polyanionic organic compound in step S3 is 4:1 - 12:1.

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