Photovoltaic glass etching additive and application thereof

Abstract

The present invention provides an additive for etching photovoltaic glass and an application thereof, belonging to the field of photovoltaic technology. The additive for etching photovoltaic glass provided by the present invention can prepare a pyramid-like structure on a glass plate by a simple and low-cost chemical etching method, thereby forming a velvet surface on the surface of the photovoltaic glass, reducing the reflectivity of the photovoltaic glass, increasing light transmission, and improving the power of the photovoltaic module. The raw materials of the additive for etching photovoltaic glass are simple and easy to obtain, the preparation method is simple, and the preparation cost of velvet photovoltaic glass can be effectively reduced, and the application value is very high.

Description

Technical Field

[0001] The invention belongs to the technical field of photovoltaics, and in particular relates to an additive for etching photovoltaic glass and application thereof. Background Art

[0002] Photovoltaic glass is a common cover material in photovoltaic systems, typically used to encapsulate silicon solar cells. However, the high reflectivity of photovoltaic glass weakens the light energy absorbed by the solar cells, thereby reducing the solar cell's photoelectric conversion efficiency.

[0003] At present, anti-reflection film coating and surface texturing technology are usually used in industrial production to reduce the emissivity of photovoltaic glass, thereby increasing the light transmittance of photovoltaic glass. Anti-reflection film coating is a method that uses the phase interference between the two media of anti-reflection film and glass to re-enter the interior of the glass, thereby increasing the transmittance of light. In the existing technology, vacuum coating method, chemical vapor deposition method and sol-gel method are usually used to prepare anti-reflection film coating, but the preparation conditions of anti-reflection film coating are strict and the process production cost is high, which leads to high production cost of solar cells. Surface texturing technology is to use an etching process to form a geometric structure of a certain area on the surface of the material. Commonly used methods are mechanical etching, laser etching, chemical corrosion, etc. However, mechanical etching and laser etching equipment are expensive and consume huge energy, which increases the cost of preparing velvet glass. Therefore, it is necessary to provide a chemical etching method with simple preparation method and low cost to prepare velvet glass. Summary of the Invention

[0004] To address the shortcomings of the prior art, the present invention provides a photovoltaic glass etching additive and its application. The photovoltaic glass etching additive provided by the present invention can produce a pyramid-like structure on a glass plate using a simple and low-cost chemical etching method, thereby forming a textured surface on the photovoltaic glass surface, thereby reducing the reflectivity of the photovoltaic glass, increasing light transmission, and improving the power of photovoltaic modules. The photovoltaic glass etching additive has simple and readily available raw materials and a simple preparation method, effectively reducing the production cost of textured photovoltaic glass and possessing high application value.

[0005] The present invention first provides an additive for photovoltaic glass etching, which comprises, by mass percentage, 5% to 10% inorganic salt, 1% to 3% oxidant, 0.01% to 0.05% surfactant, 0.5% to 5% dispersant, and the balance is water; the inorganic salt comprises any one of the following combinations:

[0006] A: Sodium sulfate and zinc dihydrogen phosphate; or

[0007] B: Potassium chloride and solid phosphorous acid; or

[0008] C: Ammonium ferric citrate and sodium acetate.

[0009] Preferably, the mass percentage of the sodium sulfate in the additive for photovoltaic glass etching is 3% to 6%; the mass percentage of the zinc dihydrogen phosphate in the additive for photovoltaic glass etching is 2% to 5%.

[0010] Preferably, the mass percentage of the potassium chloride in the additive for photovoltaic glass etching is 3% to 5%; the mass percentage of the solid phosphorous acid in the additive for photovoltaic glass etching is 3% to 5%.

[0011] Preferably, the mass percentage of the ammonium ferric citrate in the additive for photovoltaic glass etching is 3% to 5%; the mass percentage of the sodium acetate in the additive for photovoltaic glass etching is 3% to 5%.

[0012] Preferably, the oxidant comprises hydrogen peroxide; the surfactant comprises sodium lauroyl sarcosinate, lauroyl glutamate, sodium dodecylbenzenesulfonate or sodium octylsulfonate; and the dispersant comprises a polycarboxylate dispersant.

[0013] The present invention also provides the use of the above-mentioned photovoltaic glass etching additive in the preparation of textured photovoltaic glass.

[0014] Preferably, the application includes:

[0015] Evenly mixing the photovoltaic glass etching additive with the acid solution to obtain a glass etching solution;

[0016] The photovoltaic glass sheet is placed in a glass etching solution and is kept in a vertical state for etching. The etching temperature and etching time are controlled. After the etching is completed, the photovoltaic glass sheet is washed to obtain a velvet photovoltaic glass.

[0017] Preferably, the acid solution comprises one or more of hydrofluoric acid, oxalic acid or glacial acetic acid.

[0018] Preferably, the corrosion temperature is 20-25° C., and the corrosion time is 180-300 s.

[0019] Compared with the prior art, the advantages of the present invention are:

[0020] When the photovoltaic glass etching additive described in the present invention is used to prepare velvet photovoltaic glass, the additive is first formulated into a glass etching solution. The acid solution in the etching solution destroys the incomplete Si-O bonds in the photovoltaic glass, causing the Si element to dissolve in the etching solution as a soluble salt. After the Si element precipitates and decreases on the surface of the photovoltaic glass, the sodium, zinc and other elements inside are exposed. The addition of inorganic salts to the photovoltaic glass etching additive can cause the sodium and zinc salts around the photovoltaic glass to precipitate and form a template, hindering further corrosion of the photovoltaic glass by the acid solution, and ultimately etching out a pyramid structure or velvet-like surface at the defect. In addition, the photovoltaic glass etching additive can also achieve anisotropic etching of photovoltaic glass.

[0021] In the present invention, hydronium ions are generated in water by adding hydrogen peroxide, thereby inhibiting the ionization of hydrofluoric acid, increasing the concentration of hydrofluoric acid and thus increasing the reaction rate; and the addition of sodium octylsulfonate and a polycarboxylate dispersant reduces the surface tension of the glass surface, making the velvet surface etched by the glass more uniform.

[0022] The present invention adopts a simple and low-cost chemical etching method to prepare a pyramid-like structure on a glass plate, thereby forming a velvet surface on the surface of the photovoltaic glass, reducing the reflectivity of the photovoltaic glass, increasing light transmission, and improving the power of the photovoltaic module; the raw materials of the photovoltaic glass etching additive are simple and easy to obtain, the preparation method is simple, and it can effectively reduce the preparation cost of the velvet photovoltaic glass, and has high application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a diagram of the surface structure of the photovoltaic glass in Example 1.

[0024] Figure 2 This is a diagram of the surface structure of the photovoltaic glass in Example 2.

[0025] Figure 3 This is a diagram of the surface structure of the photovoltaic glass with a snowflake-like velvet surface in Example 3. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.

[0027] Example 1:

[0028] (1) Preparation of additives for photovoltaic glass etching:

[0029] 6% by mass of sodium sulfate, 4% of zinc dihydrogen phosphate, 2% of hydrogen peroxide, 0.01% of sodium octyl sulfonate, and 0.5% of a polycarboxylate dispersant are added to water and mixed evenly to obtain an additive for photovoltaic glass etching.

[0030] (2) Preparation of velvet photovoltaic glass:

[0031] Add the photovoltaic glass etching additive to 5% hydrofluoric acid by volume, mix well to obtain glass etching solution; place the photovoltaic glass sheet in the glass etching solution, keep it in a vertical state, control the etching temperature to 20°C, and the etching time to 180s to obtain the corroded photovoltaic glass sheet; use 10% hydrochloric acid by volume to wash the corroded photovoltaic glass sheet to obtain the following: Figure 1 Photovoltaic glass shown.

[0032] Figure 1 This is a diagram of the surface structure of the photovoltaic glass prepared in this embodiment. As can be seen from the figure, the acid etching solution reacts with the photovoltaic glass, and finally a pyramid-like structure is formed on the glass surface; the structure of the photovoltaic glass surface is relatively uniform, and the structural units are also relatively dense.

[0033] Example 2:

[0034] (1) Preparation of additives for photovoltaic glass etching:

[0035] 3-5% by mass of potassium chloride, 3-5% by mass of solid phosphorous acid, 1-3% by mass of hydrogen peroxide, 0.01-0.05% by mass of sodium dodecylbenzenesulfonate, and 0.5-5% by mass of a polycarboxylate dispersant are added to water and mixed uniformly to obtain an additive for photovoltaic glass etching.

[0036] (2) Preparation of velvet photovoltaic glass:

[0037] Add the photovoltaic glass etching additive to 1% hydrofluoric acid by volume, mix well to obtain the glass etching solution, and set aside. Then place the photovoltaic glass sheet in the glass etching solution, keep it in a vertical state, control the etching temperature to 20℃, and the etching time to 180s to obtain the etched photovoltaic glass sheet. Use 10% hydrochloric acid by volume to wash the etched photovoltaic glass sheet to obtain the following: Figure 2 Photovoltaic glass shown.

[0038] Figure 2 This is a diagram of the surface structure of the photovoltaic glass prepared in this embodiment. It can be seen from the figure that dense and uniform pyramid-like structures appear on the surface of the photovoltaic glass. Countless pyramid-like structures gather into a dense velvet surface, which can effectively reduce the reflectivity of the glass and thus improve its transmittance.

[0039] Example 3:

[0040] (1) Preparation of additives for photovoltaic glass etching:

[0041] 2%-3% by mass of ammonium ferric citrate, 3%-5% by mass of sodium acetate, 2% by mass of hydrogen peroxide, 0.01-0.03% by mass of sodium dodecylbenzenesulfonate, and 0.5% by mass of a polycarboxylate dispersant are added to water and mixed evenly to obtain an additive for photovoltaic glass etching.

[0042] (2) Preparation of velvet photovoltaic glass:

[0043] The photovoltaic glass is pretreated with a mixed acid solution of 1-3% by mass hydrofluoric acid, 2-3% by mass oxalic acid, and 10% by mass acetic acid for 5-10 minutes and set aside. An additive for photovoltaic glass etching is added to the hydrofluoric acid with a volume fraction of 5-8%, and the mixture is mixed evenly to obtain a glass etching solution, which is set aside.

[0044] Then, the pretreated photovoltaic glass sheet was placed in the glass etching solution, kept in a vertical state, and the etching temperature was controlled to be 20°C and the etching time was 180s to obtain the corroded photovoltaic glass sheet. The corroded photovoltaic glass sheet was washed with hydrochloric acid with a volume fraction of 10%, and the following was obtained: Figure 3 Photovoltaic glass shown.

[0045] Figure 3 This is a structural diagram of the photovoltaic glass surface with a snowflake-like velvet surface prepared in this embodiment. It can be seen from the figure that a dense, uniform snowflake-like structure is formed on the surface of the photovoltaic glass after acid etching. The surface of each structural unit is rough and not smooth, which can effectively reduce light reflection.

[0046] The embodiments described are preferred implementations of the present invention, but the present invention is not limited to the above implementations. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention are within the scope of protection of the present invention.

Claims

1. An additive for photovoltaic glass etching, characterized in that: The photovoltaic glass etching additive comprises, by mass percentage, 5% to 10% inorganic salt, 1% to 3% oxidant, 0.01% to 0.05% surfactant, 0.5% to 5% dispersant, and the balance is water; the inorganic salt is any one of the following combinations: A: Sodium sulfate and zinc dihydrogen phosphate; or B: Potassium chloride and solid phosphorous acid; or C: ammonium ferric citrate and sodium acetate; When the inorganic salt is combination A, the mass percentage of the sodium sulfate in the photovoltaic glass etching additive is 3% to 6%; the mass percentage of the zinc dihydrogen phosphate in the photovoltaic glass etching additive is 2% to 5%; When the inorganic salt is combination B, the mass percentage of the potassium chloride in the photovoltaic glass etching additive is 3% to 5%; the mass percentage of the solid phosphorous acid in the photovoltaic glass etching additive is 3% to 5%; When the inorganic salt is combination C, the mass percentage of the ammonium ferric citrate in the photovoltaic glass etching additive is 3% to 5%; the mass percentage of the sodium acetate in the photovoltaic glass etching additive is 3% to 5%; The oxidant includes hydrogen peroxide; the surfactant includes sodium lauroyl sarcosinate, lauroyl glutamic acid, sodium dodecylbenzene sulfonate or sodium octyl sulfonate; and the dispersant includes a polycarboxylate dispersant.

2. Use of the photovoltaic glass etching additive according to claim 1 in the preparation of textured photovoltaic glass.

3. The use according to claim 2, characterized in that The applications include: Evenly mixing the photovoltaic glass etching additive with the acid solution to obtain a glass etching solution; The photovoltaic glass sheet is placed in a glass etching solution and is kept in a vertical state for etching. The etching temperature and etching time are controlled. After the etching is completed, the photovoltaic glass sheet is washed to obtain a velvet photovoltaic glass.

4. The use according to claim 3, characterized in that The acid solution includes one or more of hydrofluoric acid, oxalic acid or glacial acetic acid.

5. The use according to claim 3, characterized in that The corrosion temperature is 20-25° C., and the corrosion time is 180-300 s.

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