Method for removing white spots of texturing material and texturing sheet and solar cell

Abstract

The present disclosure provides a method for removing white spots of texturing raw material and a texturing wafer and a solar cell, and belongs to the technical field of photovoltaics. The method comprises the following steps: before texturing, the texturing raw material is sequentially subjected to pickling, rough polishing and cleaning; wherein the pickling is performed by using an acid solution, the composition of the acid solution comprises HF and HCl; the rough polishing is performed by using a first alkali solution, the composition of the first alkali solution comprises at least one of NaOH and KOH; the cleaning is performed by using a second alkali solution, the second alkali solution comprises at least one of NaOH and KOH and H2O2. The method can effectively remove the white spots of the texturing raw material, and can ensure the appearance and uniformity of the texturing surface after texturing, reduce the reflectivity of the texturing wafer, and the above method does not need to add additional equipment, and the cost is low.

Description

Technical Field

[0001] This disclosure relates to the field of photovoltaic technology, and more specifically, to a method for removing white spots from texturing materials and to texturing sheets and solar cells. Background Technology

[0002] TOPCon solar cells, due to their high efficiency and low cost, have gradually become one of the mainstream technologies in the photovoltaic industry. Currently, in the manufacturing process of TOPCon cells, white spots are unavoidable in the incoming wafers. These white spots are generally left over from the wafer slicing process, caused by residues of silicon wafer cleaning solution and by adhesive rods introduced onto the wafer surface via diamond wire, which are difficult to clean in subsequent processes. Current methods for removing white spots from incoming wafers before texturing struggle to achieve both good white spot removal and good surface properties, resulting in high reflectivity after texturing.

[0003] In view of this, this disclosure is hereby made. Summary of the Invention

[0004] The purpose of this disclosure is to provide a method for removing white spots from texturing materials, as well as texturing sheets and solar cells, to solve or improve the aforementioned technical problems.

[0005] This disclosure can be implemented as follows: In a first aspect, this disclosure provides a method for removing white spots from incoming fabric for flocking, comprising the following steps: before flocking, the incoming fabric for flocking is sequentially subjected to acid washing, rough polishing, and cleaning; Acid washing is performed using an acid solution, the components of which include HF and HCl. The coarse polishing is performed using a first alkaline solution, the components of which include at least one of NaOH and KOH; The cleaning is performed using a second alkaline solution, which includes at least one of NaOH and KOH, as well as H2O2.

[0006] In an optional embodiment, the acid solution comprises 1% to 1.04% HF and 1.14% to 1.18% HCl by mass percentage.

[0007] In an optional embodiment, the acid solution comprises 1.02% HF and 1.16% HCl by mass percentage.

[0008] In an optional embodiment, the pickling temperature is 20℃~30℃, and the pickling time is 1500s~1700s.

[0009] In an optional embodiment, the first alkaline solution comprises, by mass percentage, at least one of NaOH and KOH, at a concentration of 1.98% to 2.02%.

[0010] In an optional embodiment, the first alkaline solution comprises, by mass percentage, at least 2% of NaOH and KOH.

[0011] In an optional implementation, the coarse polishing temperature is 70℃~80℃, and the coarse polishing time is 200s~400s.

[0012] In an optional embodiment, the second alkaline solution comprises, by mass percentage, at least one of NaOH and KOH (0.18% to 0.22%) and 1.07% to 1.11% H2O2.

[0013] In an optional embodiment, the second alkaline solution comprises, by mass percentage, at least 0.2% of NaOH and KOH and 1.09% of H2O2.

[0014] In an optional implementation, the cleaning temperature is 60℃~70℃ and the cleaning time is 180s~240s.

[0015] Secondly, this disclosure provides a flocking sheet, which is obtained by processing flocking material through any of the methods described in the foregoing embodiments and then flocking it.

[0016] In an optional implementation, the reflectivity of the felt does not exceed 9.5%.

[0017] Thirdly, this disclosure provides a solar cell that includes the texturing sheet of the aforementioned embodiments.

[0018] The beneficial effects of this disclosure include: The method for removing white spots from incoming texturing materials disclosed herein includes the following steps: before texturing, the incoming texturing materials are sequentially acid-washed, coarsely polished, and cleaned. Acid washing primarily removes adhesive residue and surface contaminants (such as silicone oil) from the surface of the incoming texturing materials; coarse polishing optimizes the surface smoothness of the product and improves the uniformity of the solution on the product surface after texturing; cleaning removes silicate products generated during coarse polishing, preventing them from affecting the uniformity of the texturing surface and the reflectivity of the texturing sheet.

[0019] The method for removing white spots from incoming flocking material provided in this disclosure can effectively remove white spots from incoming flocking material, and can ensure the appearance and uniformity of the flocking surface after flocking, reduce the reflectivity of flocking sheet, and the above method does not require additional equipment and has low cost. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 These are photographs showing the color spots on the incoming flocking material after it has been treated in Example 1 and then flocked again. Figure 2 The photo shows the pile surface of the pile material after being processed in Example 1 and then piled again. Figure 3 Photographs showing the color spots on the incoming flocking material after being treated in Comparative Example 1 and then flocking again. Figure 4 This is a photograph of the pile surface of the incoming pile material after being processed in Comparative Example 1 and then piled again. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions in the embodiments of this disclosure will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0023] The following provides a detailed explanation of the method for removing white spots from the incoming texturing material and the texturing sheet and solar cell.

[0024] The inventors point out that existing pre-textured contamination removal processes typically use alkaline solutions (such as NaOH) for cleaning. However, the reaction rate between alkaline solutions and adhesive residues is extremely slow, making it difficult for normal rough polishing to remove the residue completely. Extending the cleaning time or increasing the alkaline solution concentration can improve the removal effect, but it also causes excessively rapid corrosion in the normal areas of the product, affecting the surface smoothness and uniformity of the texturized surface. Additionally, ultrasonic cleaning of the incoming texturized material using ethanol, acetone, and propanol is also available, but this method is costly.

[0025] Based on this, the present disclosure provides a method for removing white spots from incoming flocking material, including the following steps: before flocking, the incoming flocking material is sequentially acid-washed, coarsely polished, and cleaned.

[0026] The pickling process mainly removes adhesive residues and surface contaminants (such as silicone oil) from the surface of the incoming texturing material; coarse polishing removes the damaged layer, optimizes the surface smoothness of the product, and improves the uniformity of the solution on the surface of the product after texturing; cleaning removes the silicate residues generated by the coarse polishing corrosion, improves the surface cleanliness of the product, and prevents them from affecting the uniformity of the texturing surface and the reflectivity of the texturing sheet.

[0027] In some alternative embodiments, acid washing is performed using an acid solution comprising HF and HCl. Specifically, the acid solution is a mixture of HF, HCl, and water.

[0028] In the above acid solution, HF can remove adhesive residue, while HCl acts as a complexing agent. Using both HF and HCl as the active ingredients in the acid solution provides superior cleaning effectiveness and a more complete reaction compared to using either HF or HCl alone.

[0029] In some alternative embodiments, the acid solution comprises 1% to 1.04% HF and 1.14% to 1.18% HCl by mass percentage.

[0030] The mass percentage of HF in the acid solution can be 1%, 1.01%, 1.02%, 1.03%, or 1.04%, or other values ​​within the range of 1% to 1.04%. If the mass percentage of HF in the acid solution is less than 1%, it is not conducive to maximizing the cleaning effect; if the mass percentage of HF in the acid solution is greater than 1.04%, it is not conducive to cost control and the removal of chemical residues.

[0031] The mass percentage of HCl in the acid solution can be 1.14%, 1.15%, 1.16%, 1.17%, or 1.18%, or other values ​​within the range of 1.14% to 1.18%. If the mass percentage of HCl in the acid solution is less than 1.14%, it is not conducive to maximizing the complexing agent's effect; if the mass percentage of HCl in the acid solution is greater than 1.18%, it is not conducive to maximizing the HF reaction.

[0032] In some typical implementations, the acid solution includes 1.02% HF and 1.16% HCl by mass percentage, which can achieve better pickling results.

[0033] In some optional embodiments, the pickling temperature is room temperature (i.e., 20℃~30℃), and the pickling time can be 1500s~1700s, such as 1500s, 1550s, 1600s, 1650s or 1700s.

[0034] In some alternative embodiments, coarse polishing is performed using a first alkaline solution, the first alkaline solution comprising at least one of NaOH and KOH.

[0035] In some alternative embodiments, the first alkaline solution comprises, by mass percentage, at least one of NaOH and KOH, at a concentration of 1.98% to 2.02%.

[0036] The mass percentage of NaOH and / or KOH contained in the first alkaline solution can be 1.98%, 1.99%, 2.00%, 2.01%, or 2.02%, or other values ​​within the range of 1.98% to 2.02%. If the mass percentage of NaOH and / or KOH contained in the first alkaline solution is less than 1.98%, it is not conducive to the removal of surface oil and dirt; if the mass percentage of NaOH and / or KOH contained in the first alkaline solution is greater than 2.02%, it is not conducive to the product manufacturing process, for example, it may lead to the product being too thin, increasing the breakage rate, and increasing process costs.

[0037] In some typical implementations, the first alkaline solution includes at least 2% NaOH and KOH by mass percentage, which can achieve better coarse polishing results.

[0038] In some alternative implementations, the coarse polishing temperature can be 70℃~80℃, such as 70℃, 75℃, or 80℃, or other values ​​within the range of 70℃~80℃. The coarse polishing time can be 200s~400s, such as 200s, 250s, 300s, 350s, or 400s, or other values ​​within the range of 200s~400s.

[0039] In some alternative embodiments, a second alkaline solution is used for cleaning, the second alkaline solution comprising at least one of NaOH and KOH and H2O2.

[0040] In the aforementioned acid solution, NaOH and / or KOH can react with hydrogen peroxide to undergo a redox reaction, while H2O2 can clean away silicates and other substances generated during the rough polishing process through the redox reaction, ensuring the cleanliness of the incoming material surface. Using NaOH and / or KOH, along with H2O2, as the active components of the second alkaline solution offers advantages over using only alkali or H2O2 as the active component of the acid solution, resulting in a superior redox reaction and more thorough removal of products and impurities.

[0041] In some alternative embodiments, the second alkaline solution comprises, by mass percentage, at least one of NaOH and KOH (0.18% to 0.22%) and 1.07% to 1.11% H2O2.

[0042] The mass percentage of NaOH and / or KOH in the second alkaline solution can be 0.18%, 0.19%, 0.2%, 0.21%, or 0.22%, or other values ​​within the range of 0.18% to 0.22%. If the mass percentage of NaOH and / or KOH in the second alkaline solution is less than 0.18%, it is not conducive to the removal of surface oil and dirt; if the mass percentage of NaOH and / or KOH in the second alkaline solution is greater than 0.22%, it is not conducive to maximizing the redox reaction and will weaken the reaction between hydrogen peroxide and alkali.

[0043] The mass percentage of H2O2 in the second alkaline solution can be 1.07%, 1.08%, 1.09%, 1.1%, or 1.11%, or other values ​​within the range of 1.07% to 1.11%. If the mass percentage of H2O2 in the second alkaline solution is less than 1.07%, it is not conducive to maximizing the redox reaction; if the mass percentage of H2O2 in the second alkaline solution is greater than 1.11%, it is not conducive to the complete reaction of the alkali.

[0044] In some typical implementations, the second alkaline solution includes at least one of NaOH and KOH and 1.09% H2O2 by mass percentage, which can achieve better cleaning results.

[0045] In some alternative implementations, the cleaning temperature can be 60°C to 70°C (e.g., 60°C, 65°C, or 70°C), and the cleaning time can be 180s to 240s (e.g., 180s, 200s, 220s, or 240s).

[0046] As described above, the method for removing white spots from texturing materials provided in this disclosure can effectively remove adhesive residues such as sticky glue and silicone oil from the surface of the texturing material, improve the surface smoothness of the product, optimize the uniformity of the texturing surface after texturing, enhance the light trapping effect, and thus improve the appearance quality and photoelectric conversion efficiency of the battery.

[0047] Accordingly, this disclosure also provides a flocking sheet, which is obtained by processing flocking material through the above method and then flocking it.

[0048] In some alternative implementations, the reflectivity of the felt does not exceed 9.5%. For example, it can be 9.2% to 9.5%.

[0049] The texturing process described in this disclosure can refer to conventional texturing processes in the art, and the texturing solution used can also be a conventional texturing solution in the art, without further elaboration or limitation here.

[0050] In addition, this disclosure also provides a solar cell containing the aforementioned texturing sheet.

[0051] The features and performance of this disclosure will be further described in detail below with reference to embodiments.

[0052] Example 1 This embodiment provides a method for removing white spots from incoming flocking material, including the following steps: S1: Pickling.

[0053] The incoming texturing material with abnormal color spots was placed in a volumetric tank containing 800L of acid solution and pickled at 25°C for 1600s. The acid solution consisted of HF, HCl, and deionized water; by mass percentage, the acid solution included 1.02% HF and 1.16% HCl.

[0054] S2: Coarse polishing.

[0055] The pickled texturing material is placed in a volumetric tank containing 800L of the first alkali solution and coarsely polished at 75°C for 300s. The first alkali solution consists of NaOH and deionized water; by mass percentage, the first alkali solution contains 2% NaOH.

[0056] S3: Cleaning.

[0057] The rough-polished texturing material was placed in a volumetric tank containing 800L of a second alkaline solution and washed at 67°C for 200s. The second alkaline solution consisted of NaOH, H2O2, and deionized water; by mass percentage, the second alkaline solution included 0.2% NaOH and 1.09% H2O2.

[0058] Example 2 The difference between this embodiment and Embodiment 1 is that in S1, the acid solution is composed of HF, HCl and deionized water; by mass percentage, the acid solution includes 1% HF and 1.14% HCl.

[0059] That is, the contents of HF and HCl are different in the acid solution.

[0060] Example 3 The difference between this embodiment and Embodiment 1 is that in S1, the acid solution is composed of HF, HCl and deionized water; by mass percentage, the acid solution includes 1.04% HF and 1.18% HCl.

[0061] That is, the contents of HF and HCl are different in the acid solution.

[0062] Example 4 The difference between this embodiment and embodiment 1 is that in S1, the incoming fabric with abnormal color spots is placed in a volumetric tank containing 800L of acid solution and pickled at 30°C for 1500s.

[0063] That is, the pickling temperature and pickling time are different.

[0064] Example 5 The difference between this embodiment and embodiment 1 is that in S1, the incoming fabric with abnormal color spots is placed in a volumetric tank containing 800L of acid solution and pickled at 20°C for 1700s.

[0065] That is, the pickling temperature and pickling time are different.

[0066] Example 6 The difference between this embodiment and Embodiment 1 is that in S2, the pickled texturing material is placed in a volumetric tank containing 800L of the first alkaline solution and coarsely polished at 75°C for 300s. The first alkaline solution consists of NaOH and deionized water; by mass percentage, the first alkaline solution includes 1.98% NaOH.

[0067] That is, the NaOH content is different in the first alkaline solution.

[0068] Example 7 The difference between this embodiment and Embodiment 1 is that in S2, the pickled texturing material is placed in a volumetric tank containing 800L of the first alkaline solution and coarsely polished at 75°C for 300s. The first alkaline solution consists of NaOH and deionized water; by mass percentage, the first alkaline solution includes 2.02% NaOH.

[0069] That is, the NaOH content is different in the first alkaline solution.

[0070] Example 8 The difference between this embodiment and Embodiment 1 is that in S2, the pickled texturing material is placed in a volumetric tank containing 800L of the first alkaline solution and coarsely polished at 70°C for 400s. The first alkaline solution consists of NaOH and deionized water; by mass percentage, the first alkaline solution includes 2% NaOH.

[0071] That is, the coarse polishing temperature and coarse polishing time are different.

[0072] Example 9 The difference between this embodiment and Embodiment 1 is that in S2, the pickled texturing material is placed in a volumetric tank containing 800L of the first alkaline solution and coarsely polished at 80°C for 200s. The first alkaline solution consists of NaOH and deionized water; by mass percentage, the first alkaline solution includes 2% NaOH.

[0073] That is, the coarse polishing temperature and coarse polishing time are different.

[0074] Example 10 The difference between this embodiment and Embodiment 1 is that in S3, the second alkaline solution is composed of NaOH, H2O2 and deionized water; by mass percentage, the second alkaline solution includes 0.18% NaOH and 1.07% H2O2.

[0075] That is, the contents of NaOH and H2O2 are different in the second alkaline solution.

[0076] Example 11 The difference between this embodiment and Embodiment 1 is that in S3, the second alkaline solution is composed of NaOH, H2O2 and deionized water; by mass percentage, the second alkaline solution includes 0.22% NaOH and 1.11% H2O2.

[0077] That is, the contents of NaOH and H2O2 are different in the second alkaline solution.

[0078] Example 12 The difference between this embodiment and Embodiment 1 is that the rough polished fabric is placed in a volumetric tank containing 800L of the second alkaline solution and washed at 35°C for 300s.

[0079] That is, the cleaning temperature and cleaning time are different.

[0080] Example 13 The difference between this embodiment and Embodiment 1 is that the rough polished fabric is placed in a volumetric tank containing 800L of the second alkaline solution and washed at 45°C for 250s.

[0081] That is, the cleaning temperature and cleaning time are different.

[0082] Comparative Example 1 The difference between this comparative example and Example 1 is that, before the texturing process, steps S1 and S2 were not performed; only step S3, the cleaning process, was performed.

[0083] Comparative Example 2 The difference between this comparative example and Example 1 is that, before the texturing process, step S1 was not performed; only step S2 (rough polishing) and step S3 (cleaning) were performed.

[0084] Comparative Example 3 The difference between this comparative example and Example 1 is that before the flocking process, step S3 is performed first, followed by step S2, and then step S1.

[0085] Comparative Example 4 The difference between this comparative example and Example 1 is that in S1, the acid solution is composed of HF, HCl and deionized water; by mass percentage, the acid solution includes 0.9% HF and 1.16% HCl.

[0086] That is, the HF content varies in acidic solutions.

[0087] Comparative Example 5 The difference between this comparative example and Example 1 is that in S1, the acid solution is composed of HF, HCl and deionized water; by mass percentage, the acid solution includes 1.1% HF and 1.16% HCl.

[0088] That is, the HF content varies in acidic solutions.

[0089] Comparative Example 6 The difference between this comparative example and Example 1 is that in S1, the acid solution is composed of HF, HCl and deionized water; by mass percentage, the acid solution includes 1.02% HF and 1.1% HCl.

[0090] That is, the HCl content varies in the acid solution.

[0091] Comparative Example 7 The difference between this comparative example and Example 1 is that in S1, the acid solution is composed of HF, HCl and deionized water; by mass percentage, the acid solution includes 1.02% HF and 1.2% HCl.

[0092] That is, the HCl content varies in the acid solution.

[0093] Comparative Example 8 The difference between this comparative example and Example 1 is that in S2, the first alkaline solution is composed of NaOH and deionized water; by mass percentage, the first alkaline solution includes 1.95% NaOH.

[0094] That is, the NaOH content is different in the first alkaline solution.

[0095] Comparative Example 9 The difference between this comparative example and Example 1 is that in S2, the first alkaline solution is composed of NaOH and deionized water; by mass percentage, the first alkaline solution includes 2.05% NaOH.

[0096] That is, the NaOH content is different in the first alkaline solution.

[0097] Comparative Example 10 The difference between this comparative example and Example 1 is that in S3, the second alkaline solution is composed of NaOH, H2O2 and deionized water; by mass percentage, the second alkaline solution includes 0.15% NaOH and 1.09% H2O2.

[0098] That is, the NaOH content is different in the second alkaline solution.

[0099] Comparative Example 11 The difference between this comparative example and Example 1 is that in S3, the second alkaline solution is composed of NaOH, H2O2 and deionized water; by mass percentage, the second alkaline solution includes 0.25% NaOH and 1.09% H2O2.

[0100] That is, the NaOH content is different in the second alkaline solution.

[0101] Comparative Example 12 The difference between this comparative example and Example 1 is that in S3, the second alkaline solution is composed of NaOH, H2O2 and deionized water; by mass percentage, the second alkaline solution includes 0.2% NaOH and 1.05% H2O2.

[0102] That is, the H2O2 content is different in the second alkaline solution.

[0103] Comparative Example 13 The difference between this comparative example and Example 1 is that in S3, the second alkaline solution is composed of NaOH, H2O2 and deionized water; by mass percentage, the second alkaline solution includes 0.2% NaOH and 1.15% H2O2.

[0104] That is, the H2O2 content is different in the second alkaline solution.

[0105] Test case The texturing materials obtained from Examples 1-13 and Comparative Examples 1-13 were texturing in the following manner to obtain texturing sheets. The surface condition and reflectivity of each texturing sheet were compared, and the results are shown in Table 1. Figures 1 to 4 As shown. Examples 1 to 13 are considered "OK", while Comparative Examples 1 to 13 are considered "NG".

[0106] The texturing method is as follows: The texturing sheet is placed in a volumetric tank containing 800L of texturing solution and texturized at 25℃ for 1600s. The texturing solution consists of NaOH, texturing additives, and deionized water; by mass percentage, the texturing solution includes 0.8% NaOH and 0.2% texturing additives. The texturing additives were purchased from Jiaxing Xiaochen Photovoltaic Technology Co., Ltd., model number KT08A-E03.

[0107] Table 1 Comparison Results

[0108] As can be seen from Table 1, the method provided in this embodiment can effectively remove color spots from incoming materials and obtain a uniform velvet surface, thereby reducing the reflectivity of the velvet sheet.

[0109] A comparison of Comparative Example 1 and Example 1 shows that cleaning alone cannot remove the adhesive residue and silicone oil left on the slabs, resulting in white spots on the textured surface after texturing. The adhesion of dirt prevents the textured surface from growing properly. A comparison of Comparative Example 2 and Example 1 shows that coarse polishing and cleaning alone are also insufficient to effectively remove the adhesive residue and silicone oil left on the slabs, resulting in white spots on the textured surface after texturing. The adhesion of dirt prevents the textured surface from growing properly. A comparison of Comparative Example 3 and Example 1 shows that changing the order of steps S1 to S3 also fails to achieve satisfactory spot removal and a uniform textured surface. Therefore, only by first removing the adhesive residue and silicone oil with an acid solution as provided in this disclosure can a normal textured surface be grown.

[0110] As can be seen from Comparative Examples 4-13 and Example 1, when the conditions for pickling, rough polishing or washing are not set properly, it will be difficult to effectively remove the white spots on the incoming material for velveting and ensure the appearance and uniformity of the velvet surface after velveting, ultimately increasing the reflectivity of the velvet sheet.

[0111] In summary, the method for removing white spots from incoming texturing materials provided in this disclosure can effectively remove white spots from the texturing material, ensure the appearance and uniformity of the texturing surface after texturing, reduce the reflectivity of the texturing sheet, and enhance the light-trapping effect, thereby improving the appearance quality and photoelectric conversion efficiency of the battery. Furthermore, the above method requires no additional equipment, has low cost, and is suitable for large-scale production and routine handling of color spots on incoming materials.

[0112] The above description is merely a preferred embodiment of this disclosure and is not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A method for removing white spots from incoming flocking material, characterized in that, Includes the following steps: Before the texturing process, the incoming texturing material is sequentially pickled, coarsely polished, and washed. The acid washing process involves using an acid solution, the components of which include HF and HCl. The coarse polishing is performed using a first alkaline solution, the first alkaline solution comprising at least one of NaOH and KOH; The cleaning is performed using a second alkaline solution, which includes at least one of NaOH and KOH, as well as H2O2.

2. The method according to claim 1, characterized in that, The acid solution comprises 1% to 1.04% HF and 1.14% to 1.18% HCl by mass percentage; Preferably, the acid solution comprises 1.02% HF and 1.16% HCl by mass percentage.

3. The method according to claim 2, characterized in that, The pickling temperature is 20℃~30℃, and the pickling time is 1500s~1700s.

4. The method according to claim 1, characterized in that, The first alkaline solution comprises, by mass percentage, at least one of NaOH and KOH, at a concentration of 1.98% to 2.02%. Preferably, by mass percentage, the first alkaline solution comprises at least 2% of NaOH and KOH.

5. The method according to claim 4, characterized in that, The temperature for rough polishing is 70℃~80℃, and the polishing time is 200s~400s.

6. The method according to claim 1, characterized in that, The second alkaline solution comprises, by mass percentage, at least one of NaOH and KOH (0.18% to 0.22%) and 1.07% to 1.11% H2O2. Preferably, the second alkaline solution comprises, by mass percentage, at least one of NaOH and KOH (0.2%) and 1.09% H2O2.

7. The method according to claim 6, characterized in that, The cleaning temperature is 60℃~70℃, and the cleaning time is 180s~240s.

8. A type of flocking sheet, characterized in that, It is obtained by processing incoming materials for flocking using the method described in any one of claims 1 to 7, followed by flocking.

9. The flocking sheet according to claim 8, characterized in that, The reflectivity of the fabricated sheet does not exceed 9.5%.

10. A solar cell, characterized in that, The solar cell contains the texturing sheet as described in claim 8 or 9.

Images