Photovoltaic glass and preparation method thereof
阅读说明：本技术 一种光伏玻璃及其制备方法 (Photovoltaic glass and preparation method thereof ) 是由 田文顺 陈玉海 刘建军 于 2020-12-30 设计创作，主要内容包括：公开了一种光伏玻璃,包括光伏玻璃基体和含二氧化硅增透膜,所述增透膜通过含二氧化硅溶胶在所述光伏玻璃基体表面形成；该含二氧化硅溶胶由酸催化溶胶和碱催化溶胶混合而成；二者均含有表面活性剂。该光伏玻璃不仅透光率高同时机械硬度较高。(The photovoltaic glass comprises a photovoltaic glass substrate and an antireflection film containing silicon dioxide, wherein the antireflection film is formed on the surface of the photovoltaic glass substrate through sol containing silicon dioxide; the silica-containing sol is formed by mixing acid catalysis sol and alkali catalysis sol; both contain a surfactant. The photovoltaic glass is high in light transmittance and high in mechanical hardness.)
1. The photovoltaic glass comprises a photovoltaic glass substrate and an antireflection film containing silicon dioxide, wherein the antireflection film is formed on the surface of the photovoltaic glass substrate through sol containing silicon dioxide; the silica-containing sol is formed by mixing acid catalysis sol and alkali catalysis sol; the method is characterized in that the acid catalysis sol and the alkali catalysis sol both contain a surfactant.
2. The photovoltaic glass according to claim 1, wherein the acid-catalyzed sol is obtained by mixing, stirring and aging trialkoxymethylsilane serving as a precursor, absolute ethyl alcohol serving as a solvent and gemini quaternary ammonium salt serving as a surfactant under acid catalysis; advantageously, the trialkoxymethylsilane is selected from one or more of trimethoxymethylsilane, triethoxymethylsilane, tripropoxymethylsilane; and/or, the structural formula of the gemini quaternary ammonium salt is as follows: c14H29-[N(CH3)2]-(CH2CH2)-[N(CH3)2]-C14H29·2Br。
3. The photovoltaic glass of claim 1, wherein the acid-catalyzed sol is prepared by the following method: mixing trialkoxymethylsilane, absolute ethyl alcohol, deionized water, gemini quaternary ammonium salt and hydrochloric acid, stirring for 2-6 hours, and aging for 2-4 days to obtain the finished product.
4. The photovoltaic glass of claim 3, wherein the molar ratio of trialkoxymethylsilane, absolute ethanol, deionized water, gemini quaternary ammonium salt, and hydrochloric acid is 1: (25-35): (2-4): (0.4-0.8): (0.01-0.03).
5. The photovoltaic glass according to claim 1, wherein the alkali-catalyzed sol is obtained by mixing, stirring and aging tetraalkoxysilane serving as a precursor, absolute ethyl alcohol serving as a solvent and polyethylene glycol serving as a surfactant under the catalysis of alkali; advantageously, the tetraalkoxysilane is selected from one or more of tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane; and/or, the polyethylene glycol is PEG 2000.
6. The photovoltaic glass of claim 1, wherein the alkali-catalyzed sol is prepared by the following method: mixing and stirring tetraalkoxysilane, absolute ethyl alcohol, deionized water and ammonia water for 2-6 hours, and aging for 4-6 days; adding polyethylene glycol, and refluxing at 70-80 deg.C for 8-24 hr.
7. The photovoltaic glass of claim 6, wherein the molar ratio of tetraalkoxysilane, absolute ethanol, deionized water, ammonia, polyethylene glycol is 1: (35-55): (1-3): (0.8-1.2): (0.2-0.4).
8. The photovoltaic glass of claim 1, wherein the volume ratio of the acid-catalyzed sol to the base-catalyzed sol is from 1: (3-5).
9. A method of making a photovoltaic glass as described in any of claims 1-8, comprising:
filtering the silica-containing sol by using a microporous filter membrane;
a dip-coating method is adopted to carry out coating film-coating on the photovoltaic glass substrate at a speed of 80-100 mm/min;
keeping the temperature at 350-450 ℃ for 1-3h, and naturally cooling to room temperature.
10. The method of claim 9, wherein the photovoltaic glass substrate is selected from K9 glass.
Technical Field
The invention belongs to the technical field of photovoltaics, and relates to photovoltaic glass and a preparation method thereof.
Background
Solar Photovoltaic technology (photovoltaics) is a technology for converting solar energy into electricity, and starts in the 50 s of the 20 th century, and the core of the technology is a semiconductor substance capable of releasing electrons. In the solar photovoltaic technology, the most key core component is a crystalline silicon solar cell in a photoelectric device at present; secondly, the key core component is a photovoltaic glass cover plate; the latter is used to protect the crystalline silicon solar cell from external stress factors. The light transmission performance of photovoltaic glass is therefore an important factor affecting the efficiency and cost of solar photovoltaic modules.
Generally speaking, compared with the development of a crystalline silicon solar cell with higher efficiency, the development of the photovoltaic glass with high light transmittance is lower in cost and easier to realize technically. Therefore, the development of photovoltaic glass having high light transmittance is an urgent problem to be overcome, both for the module manufacturing enterprises and for the demand on the photovoltaic market.
The development of high-transmittance photovoltaic glass mainly focuses on the following aspects:
firstly, the content of transition metal elements in the raw materials of the photovoltaic glass is reduced, the oxidizing atmosphere in the combustion atmosphere is ensured, and the Redox value is reduced, so that the light transmittance of the photovoltaic glass is improved. However, the technical route has high raw material treatment cost and limited lifting space, and generally can only improve the light transmittance to about 91%.
Secondly, a light trapping structure is manufactured on the surface of the photovoltaic glass through a micro-nano machining process, and light is incident from the surface of the glass and is emitted from the light trapping structure by utilizing a total reflection phenomenon. However, the processing technology of the technical route is complex, and the photovoltaic glass is difficult to popularize and apply on large-area photovoltaic glass; meanwhile, the manufacturing cost is high, and the large-scale use is difficult.
Thirdly, a film with proper thickness, namely an antireflection film, is plated on the surface of the glass, and the principle is that light rays generate an interference phenomenon from the front surface and the rear surface of the film, so that the light transmittance of the light rays in the photovoltaic glass can be improved. The method for plating the antireflection film is very simple and has high economic benefit, so the method is a very common optimization method.
Chinese patent application CN107032359A discloses a preparation method of silica sol and a preparation method of photovoltaic glass, the preparation method of photovoltaic glass comprises: mixing methyltriethoxysilane, tetraethoxysilane, water and an organic solvent under the action of an acidic catalyst respectively, and reacting to generate acidic silica hydrosol; mixing an alcohol ether solvent and an acidic silica hydrosol to obtain a silica sol; providing a glass substrate, and forming a film on the surface of glass by using silica sol; providing a template for nano imprinting, wherein the surface of the template is provided with a pattern, and transferring the pattern of the template to a thin film on the surface of glass by an imprinting method to form the photovoltaic glass. The method can obtain the photovoltaic glass with the antireflection structure with large area and low cost.
Chinese patent application CN110002767A discloses a preparation method of a high light transmittance hydrophobic coating film for photovoltaic glass, comprising the following steps: (1) mixing a silicon source and an organic solvent, and carrying out primary sol-gel reaction under acid catalysis to obtain mixed sol A; (2) adding organic siloxane and a surfactant into the mixed sol A, and carrying out secondary sol-gel reaction under stirring to obtain mixed sol B; (3) and aging the mixed sol B, coating and performing heat treatment to obtain the hydrophobic coating. According to the invention, the coating precursor is prepared by a two-step sol-gel method and an optimized organic solvent, and the film obtained after coating has high hydrophobicity, high light transmittance and antifogging property, so that the light transmittance of the solar photovoltaic glass can be improved, and the photoelectric conversion efficiency of the solar cell can be improved.
However, the above patents all have the technical drawback of having undesirable mechanical properties. In view of the above technical defects, there is still a need to find a photovoltaic glass with high light transmittance and high mechanical hardness and a preparation method thereof.
Disclosure of Invention
The invention aims to provide photovoltaic glass with high light transmittance and high mechanical strength and a preparation method thereof.
In order to achieve the above object, in one aspect, the present invention provides a photovoltaic glass, including a photovoltaic glass substrate and an antireflection film containing silica, where the antireflection film is formed on the surface of the photovoltaic glass substrate by using a sol containing silica; the silica-containing sol is characterized by being prepared by mixing acid catalysis sol and alkali catalysis sol.
According to the photovoltaic glass, trialkoxymethylsilane is used as a precursor of the acid catalysis sol, absolute ethyl alcohol is used as a solvent, gemini quaternary ammonium salt is used as a surfactant, and the acid catalysis sol is obtained by mixing, stirring and aging under acid catalysis.
The photovoltaic glass is characterized in that trialkoxymethylsilane is selected from one or more of trimethoxymethylsilane, triethoxymethylsilane and tripropoxymethylsilane.
The photovoltaic glass provided by the invention is characterized in that the structural formula of the gemini quaternary ammonium salt is as follows: c14H29-[N(CH3)2]-(CH2CH2)-[N(CH3)2]-C14H29·2Br。
In the present invention, Gemini quaternary ammonium salt is prepared according to the method of Limin et al.
The photovoltaic glass provided by the invention is prepared by the following method: mixing trialkoxymethylsilane, absolute ethyl alcohol, deionized water, gemini quaternary ammonium salt and hydrochloric acid, stirring for 2-6 hours, and aging for 2-4 days to obtain the finished product.
The photovoltaic glass provided by the invention is prepared from trialkoxymethylsilane, absolute ethyl alcohol, deionized water, gemini quaternary ammonium salt and hydrochloric acid in a molar ratio of 1: (25-35): (2-4): (0.4-0.8): (0.01-0.03).
The photovoltaic glass is obtained by mixing, stirring and aging the alkali-catalyzed sol by taking tetraalkoxysilane as a precursor, absolute ethyl alcohol as a solvent and polyethylene glycol as a surfactant under the catalysis of alkali.
The photovoltaic glass provided by the invention is characterized in that the tetraalkoxysilane is selected from one or more of tetramethoxysilane, tetraethoxysilane and tetrapropoxysilane.
The photovoltaic glass provided by the invention, wherein the polyethylene glycol is PEG 2000.
The preparation method of the alkali-catalyzed sol comprises the following steps: mixing and stirring tetraalkoxysilane, absolute ethyl alcohol, deionized water and ammonia water for 2-6 hours, and aging for 4-6 days; adding polyethylene glycol, and refluxing at 70-80 deg.C for 8-24 hr.
The photovoltaic glass provided by the invention is characterized in that the molar ratio of tetraalkoxysilane to absolute ethyl alcohol to deionized water to ammonia water to polyethylene glycol is 1: (35-55): (1-3): (0.8-1.2): (0.2-0.4).
The photovoltaic glass provided by the invention is characterized in that the volume ratio of the acid catalysis sol to the alkali catalysis sol is 1: (3-5).
In another aspect, the invention also provides a preparation method of the photovoltaic glass, which comprises the following steps:
filtering the silica-containing sol by using a microporous filter membrane;
a dip-coating method is adopted to carry out coating film-coating on the photovoltaic glass substrate at a speed of 80-100 mm/min;
keeping the temperature at 350-450 ℃ for 1-3h, and naturally cooling to room temperature.
The preparation method provided by the invention is characterized in that the photovoltaic glass substrate is selected from K9 glass.
The photovoltaic glass has the beneficial technical effects that compared with the prior art, the photovoltaic glass has high light transmittance and higher mechanical hardness.
Detailed Description
It must be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include both one and more than one (i.e., two, including two) unless the context clearly dictates otherwise.
References to "comprising," "including," "having," and similar terms in this specification are not intended to exclude the presence of any optional components, steps or procedures, whether or not any optional components, steps or procedures are specifically disclosed. In order to avoid any doubt, all methods claimed through use of the term "comprising" may include one or more additional steps, apparatus parts or components and/or materials unless stated to the contrary. In contrast, the term "consisting of … …" excludes any component, step, or procedure not specifically recited or recited. Unless otherwise specified, the term "or" refers to the listed members individually as well as in any combination.
Furthermore, the contents of any referenced patent or non-patent document in this application are incorporated by reference in their entirety, especially with respect to definitions disclosed in the art (where not inconsistent with any definitions specifically provided herein) and general knowledge.
In the present invention, parts are parts by weight unless otherwise indicated, temperatures are indicated in ° c or at ambient temperature, and pressures are at or near atmospheric. There are many variations and combinations of reaction conditions (e.g., component concentrations, desired solvents, solvent mixtures, temperatures, pressures, and other reaction ranges) and conditions that can be used to optimize the purity and yield of the product obtained by the process. Only reasonable routine experimentation will be required to optimize such process conditions.
Example 1
Mixing and stirring triethoxymethylsilane, absolute ethyl alcohol, deionized water, gemini quaternary ammonium salt and hydrochloric acid for 4 hours and aging for 3 days to obtain acid catalytic sol; the molar ratio of the triethoxymethylsilane to the absolute ethyl alcohol to the deionized water to the gemini quaternary ammonium salt to the hydrochloric acid is 1: 30: 3: 0.6: 0.02; wherein, the structural formula of the gemini quaternary ammonium salt is as follows: c14H29-[N(CH3)2]-(CH2CH2)-[N(CH3)2]-C14H29·2Br。
Mixing tetraethoxysilane, absolute ethyl alcohol, deionized water and ammonia water, stirring for 4 hours, and aging for 5 days; adding polyethylene glycol, and refluxing at 75 deg.C for 12h to obtain base-catalyzed sol; the molar ratio of tetraethoxysilane, absolute ethyl alcohol, deionized water, ammonia water and polyethylene glycol is 1: 45: 2: 1: 0.3; wherein, the polyethylene glycol is PEG 2000.
According to the volume ratio of the acid catalysis sol to the alkali catalysis sol of 1: and 4, stirring and mixing the two for 2 hours to obtain the silica-containing sol.
Filtering the silica-containing sol by using a microporous filter membrane with the pore diameter of 0.2 micron;
a dip-coating method is adopted to carry out coating film lifting on a photovoltaic glass substrate (K9 glass) at a speed of 90 mm/min; keeping the temperature at 400 ℃ for 2h, and naturally cooling to room temperature.
Comparative example 1
Replacing triethoxymethylsilane with tetraethoxysilane; otherwise, the same procedure as in example 1 was repeated.
Comparative example 2
The procedure of example 1 was otherwise the same as in example 1 except that no gemini quaternary ammonium salt was added.
Comparative example 3
The procedure of example 1 was repeated except that PEG 2000 was not added.
Performance testing
The average light transmission (%) of the photovoltaic glass in the wavelength range of 400-800nm is measured by using an ultraviolet-visible spectrophotometer, and the mechanical hardness is measured according to GB/T6739-2006 and by using a Chinese high-grade drawing pencil (20 grades are divided into 9B to 9H from soft to hard).
The results are shown in Table 1.
TABLE 1
Glass sample
Light transmittance (%)
Mechanical strength
Example 1
95.2
6H
Comparative example 1
94.6
5H
Comparative example 2
93.7
3H
Comparative example 3
95.0
4H
As a result, it can be seen that example 1 of the present application has not only high light transmittance but also high mechanical hardness as compared with comparative examples 1 to 3.
Without wishing to be bound by any theory, the combination of a particular type of acid-catalyzed sol and base-catalyzed sol in combination with a particular surfactant results in an improvement in the above-described technical effect.
It should be understood that the detailed description of the invention is merely illustrative of the spirit and principles of the invention and is not intended to limit the scope of the invention. Furthermore, it should be understood that various changes, substitutions, deletions, modifications or adjustments may be made by those skilled in the art after reading the disclosure of the present invention, and such equivalents are also within the scope of the invention as defined in the appended claims.