A rare earth europium complex, its POE light-converting adhesive film and preparation method thereof

Abstract

The present invention belongs to the field of solar cell encapsulation film and its preparation, and particularly relates to a rare earth europium complex EuMFT containing a reactive double bond and POE / POE- g Preparation method of PHEMA / EuMFT light-converting adhesive film. First, prepare an ethanol solution of europium chloride, and use methacrylic acid (MAA), 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione (FTFA) as ligands and triphenylphosphine oxide (TPPO) as a co-ligand to synthesize the rare earth fluorescent complex Eu(MMA)(FTFA)2TPPO2 (EuMFT). The complex has good fluorescence effect. EuMFT is mixed with the modifier POE- g The POE light-converting adhesive film provided by the present invention has long-term light-converting effect and UV resistance, and also has good bonding performance.

Description

Technical Field

[0001] The present invention belongs to the field of solar cell encapsulation adhesive films and preparation thereof, and particularly relates to a rare earth europium complex containing a reactive double bond, a POE light-converting adhesive film containing the rare earth europium complex and a preparation method thereof. Background Art

[0002] Solar energy is a sustainable and clean energy source, and crystalline silicon solar cells play a leading role in light conversion. To prevent the cells from being damaged in harsh environments such as light and UV rays over a long period of time, they are usually protected with excellent encapsulation films. POE has high transmittance, high volume resistivity, and low water vapor permeability, making it a good encapsulation material. Since the spectrum of response of silicon solar cells does not match the solar energy spectrum, the conversion efficiency remains very low. How to broaden the spectral response of cells and improve the efficiency of solar cells is an urgent problem that the solar cell industry needs to solve. Selecting down-shifting species to convert ultraviolet light, which solar cells cannot respond to, into visible light is an effective way to improve the conversion efficiency of photovoltaic modules.

[0003] Europium complexes absorb ultraviolet light and emit visible light that solar cells can respond to. This not only improves solar cell conversion efficiency but also effectively addresses the problem of traditional UV absorbers and antioxidants, which absorb UV light and convert it into heat, leading to energy loss in the battery and becoming ineffective and difficult to remove after long-term use. Conventional small-molecule europium complex light-conversion agents have poor compatibility with POE and tend to migrate to the substrate surface during use, causing the film to lose its light-conversion properties. There is an urgent need to develop europium complexes with improved compatibility with POE and superior light-conversion and UV-resistance. Summary of the Invention

[0004] Based on the above technical problems, the purpose of the present invention is to provide a rare earth europium complex containing a reactive double bond and a POE light-converting adhesive film, as well as their preparation methods.

[0005] The present invention first uses methacrylic acid (MAA) and 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione (FTFA) as ligands and triphenylphosphine oxide (TPPO) as a co-ligand to synthesize a rare earth europium complex EuMFT with a reactive double bond, and then combines EuMFT and a modifier POE- g -PHEMA and other additives are added to POE, because POE- g -PHEMA and EuMFT have a strong interaction force, while POE- gThe good compatibility of PHEMA and POE allows EuMFT to be evenly dispersed in POE to create the film raw material, which is then laminated and cross-linked to produce the light-converting film. During the lamination and cross-linking process, EuMFT bonds to the POE molecular chains through a double-bond addition reaction, forming a high-molecular-weight light-converting agent. This imparts permanent light-converting and UV-resistant properties to the film, preventing the small-molecule light-converting agent from migrating to the POE surface during use and becoming ineffective. Furthermore, the introduction of polar components effectively enhances intermolecular forces, giving the light-converting film improved bonding properties.

[0006] The present invention first provides a rare earth europium complex containing a reactive double bond, with rare earth europium as a central ion, methacrylic acid (MAA) and 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione (FTFA) as ligands, and triphenylphosphine oxide (TPPO) as a co-ligand; the rare earth europium complex has a reactive double bond, and its structural formula is as follows:

[0007] .

[0008] The present invention further provides a method for preparing the above-mentioned rare earth europium complex containing a reactive double bond, which specifically comprises the following steps:

[0009] (1) Prepare ethanol solutions of EuCl3, MAA, FTFA, and TPPO respectively;

[0010] The preparation of the EuCl3 ethanol solution can be: EuCl3 or its hydrate is dissolved in ethanol to prepare the EuCl3 ethanol solution; or Eu2O3 is reacted with hydrochloric acid until crystals appear, and ethanol is added to prepare the EuCl3 ethanol solution; wherein, the reaction temperature of the reaction of Eu2O3 with hydrochloric acid is 60-100 ° C, and the reaction time is 0.5-3 h.

[0011] Furthermore, an appropriate amount of Eu2O3 and hydrochloric acid were added to a three-necked round-bottom flask, placed in an oil bath, and mechanically stirred at 60-90°C until the solution became clear from turbidity. Further stirring resulted in the appearance of crystals, and an appropriate amount of ethanol was added to obtain an ethanol solution of EuCl3.

[0012] (2) Preparation of rare earth europium fluorescent complex: The ethanol solutions of MAA, FTFA, and TPPO were added dropwise to the ethanol solution of EuCl3, and triethylamine was used as a pH regulator to synthesize the rare earth europium complex Eu(MMA)(FTFA)2TPPO2, which was labeled as EuMFT.

[0013] Among them, the molar ratio of EuCl3, MAA, FTFA and TPPO is 1:1:2:2.

[0014] More specifically, the specific steps of step (2) are: preparing MAA ethanol solution, FTFA ethanol solution and TPPO ethanol solution respectively; dropping MAA ethanol solution into EuCl3 ethanol solution, adding pH regulator to adjust pH to 6-7, reaction temperature to 60-80°C, and fully reacting; then dropping FTFA ethanol solution, and fully reacting; finally dropping TPPO ethanol solution, and reacting to produce precipitate; collecting the precipitate by centrifugation, washing and drying.

[0015] Further, weighed MAA was added dropwise to an ethanolic solution of EuCl₃. Triethylamine was added to adjust the pH to approximately 6-7. After a reaction time of 1-2 hours, FTFA was added dropwise, and the reaction continued for 1-2 hours. Then, an ethanolic solution of TPPO was added dropwise, and the reaction continued for 3-5 hours. The reaction produced a precipitate, which was washed three times with ethanol and dried to obtain the complex EuMFT.

[0016] The rare earth europium complex containing a reactive double bond provided by the present invention has light conversion and fluorescence properties and can be used to prepare POE light conversion adhesive film.

[0017] The present invention also provides a POE light-converting adhesive film containing the rare earth europium complex, which comprises, by weight percentage:

[0018] EuMFT 0.15-0.6 wt%

[0019] Modifier 4-12 wt%

[0020] Crosslinking agent 1-3 wt%

[0021] Antioxidant 0.05-5 wt%

[0022] UV absorber 0.03-4 wt%

[0023] POE margin.

[0024] Among them, the modifier is maleic anhydride, acrylic acid, glycidyl methacrylate, citric acid, itaconic acid, palmitic acid, stearic acid, PS- g -PA、PS- b -PA、MA- g -LDPE、MA- g -EVA, ABS- g -MAH、POE- g -PHEMA、POE- g -MAH、POE- g -NH2, POE-g-GMA or more, preferably POE- g -PHEMA.

[0025] The crosslinking agent is one or more of dicumyl peroxide (DCP), benzoyl peroxide (BPO), di-tert-butyl peroxide (DTBP), diethylenetriamine (DTA), tert-butyl peroxycarbonate-2-ethylhexyl ester (TBEC), 2,5-dimethyl-2,5-di-tert-butyl peroxyhexane (bis-25), ethylene glycol diacetate (EGDE), ethylene glycol diacrylate (EGDA), diisopropylbenzene hydroperoxide (DBHP), and N,N-methylenebisacrylamide (MBA), preferably tert-butyl peroxycarbonate-2-ethylhexyl ester (TBEC).

[0026] The antioxidants include aromatic amine antioxidants such as diaryl secondary amines, p-phenylenediamine, ketone amines, aldehyde amines, etc., hindered phenol antioxidants such as antioxidant 1010, antioxidant 1076, 2,6-di-tert-butyl-4-methylphenol, antioxidant 1098, etc., auxiliary antioxidants such as phosphites, antioxidant 168, thioethers, etc., preferably aromatic amine antioxidants, more preferably antioxidant 1010.

[0027] The ultraviolet absorber is a light stabilizer such as light stabilizer GW-540 (ingredient: tris (1,2,2,6,6-pentamethylpiperidinyl) phosphite), light stabilizer 744 (ingredient: 4-benzoyloxy-2,2,6,6-tetramethylpiperidine), light stabilizer HPT (ingredient: hexamethylphosphoric triamide), ultraviolet absorber RMB (ingredient: resorcinol monobenzoate), ultraviolet absorber UVP-327 (ingredient: 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole), ultraviolet absorber UV-531 (ingredient: 2-hydroxy-4-n-octyloxybenzophenone), ultraviolet absorber UV-9 (ingredient: 2-hydroxy-4-methoxybenzophenone), ultraviolet absorber UV-P (ingredient: 2-(2'-hydroxy-5'-methylphenyl)benzotriazole), preferably an ultraviolet absorber; more preferably an ultraviolet absorber UV-531.

[0028] The present invention also provides the above-mentioned modifier POE- g -PHEMA preparation method: HEMA and initiator DCP are mixed evenly with a small amount of acetone until completely dissolved. POE is weighed and mixed with the acetone solution and stirred evenly. The mixture is allowed to stand in a fume hood for a period of time until the acetone is completely evaporated. The two groups of mixtures are added to the internal mixer and mixed after reaction. The grafted product POE- g -PHEMA.

[0029] The preparation method of the above-mentioned POE light-converting adhesive film is to blend the pre-dried POE particles with the rare earth europium complex containing reactive double bonds of the present invention, a modifier, a cross-linking agent and other additives using an internal mixer, and then laminate and cure on a flat vulcanizer to prepare POE / POE- g-PHEMA / EuMFT light-converting film.

[0030] Furthermore, the POE particles were dried in an oven, and then the set ratio of EuMFT and 4-12 wt% of POE- g -PHEMA is blended with 1-3 wt% of a crosslinker, TBEC, 0.05-5 wt% of an antioxidant, and 0.03-4 wt% of a UV absorber using an internal mixer. The film is then laminated and cured on a flat-plate vulcanizer to produce a light-converting adhesive film. The internal mixer temperature is set to 80-90°C, the speed is set to 40-60 r / min, the hot pressing temperature is set to 150-160°C, and the hot pressing time is set to 10-15 minutes. After the hot pressing is completed, the film is removed and cold pressed at room temperature for 5-10 minutes.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The present invention uses MAA and FTFA as ligands and TPPO as co-ligand to synthesize a rare earth europium complex containing a reactive double bond, EuMFT. g -PHEMA is added to the POE matrix to prepare a light-converting film. The light-converting property of EuMFT can convert ultraviolet light in the 300 nm-400 nm range that cannot be used by solar cells into visible light with a characteristic wavelength of 612 nm, thereby improving the conversion efficiency of the cell. g -PHEMA and EuMFT generate strong intermolecular forces, resulting in uniform dispersion of EuMFT within the matrix. During subsequent lamination and crosslinking, the double bonds of EuMFT participate in the reaction, further firmly bonding to the POE molecular chains to form a high-molecular-weight light-converting agent. This avoids the problem of small-molecule light-converting agents migrating and concentrating on the substrate surface during use, causing failure. The light-converting adhesive film prepared by this invention not only exhibits long-lasting light conversion and UV resistance, but also exhibits superior bonding properties compared to conventional POE adhesive films. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is the infrared spectrum of EuMFT prepared in the present invention.

[0034] Figure 2 This is the ultraviolet absorption spectrum of EuMFT prepared in the present invention.

[0035] Figure 3 : The fluorescence spectra of the complex EuMFT in the example and the complexes in comparative examples 3-6. DETAILED DESCRIPTION

[0036] The present invention is not limited to the following specific embodiments. Based on the disclosure of the present invention, a person skilled in the art may adopt a variety of other specific embodiments to implement the present invention. Any simple changes or modifications made to the design structure and concept of the present invention fall within the scope of protection of the present invention. It should be noted that the embodiments and features of the embodiments of the present invention may be combined with each other unless they conflict.

[0037] Unless otherwise defined, the technical terms used in the following examples have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. The materials and reagents used in the following examples, unless otherwise specified, are conventional materials and reagents and can be purchased commercially.

[0038] The POE particles used in the following specific examples were purchased from The Dow Chemical Company, USA; g -PHEMA was laboratory-made; TBEC was purchased from Shangyu Shaofeng Chemical Co., Ltd.; antioxidant 1010 was purchased from Tianjin Li'anlong New Materials Co., Ltd.; UV absorber UV-531 was purchased from Changzhou Youfeng Chemical Co., Ltd. Eu2O3 and TPPO were purchased from Aladdin Reagent Co., Ltd.; FTFA was purchased from Shanghai MacLean Biochemical Technology Co., Ltd.

[0039] The crosslinker POE-g-PHEMA used in the following specific examples of the present invention was prepared as follows: Preparation of POE-g-PHEMA: HEMA (1.8 g) and the initiator DCP (0.18 g) were uniformly mixed with a small amount of acetone until completely dissolved. 35 g of POE was weighed and mixed with the acetone solution, stirring evenly. The mixture was allowed to stand in a fume hood for a period of time until the acetone was completely evaporated. The two mixtures were added separately to an internal mixer set at 150°C and 60 rpm. The reaction was continued for 10 minutes, and the grafted product was removed.

[0040] Purification of the grafted product: Weigh 2 g of the POE-grafted product, cut it into small particles, place it in a flask containing 100 mL of xylene, heat it to 140°C with stirring until the particles are fully dissolved, then add it dropwise to 500 mL of methanol. Filter out the precipitated flocculent material. Repeat this process twice, then dry it in a vacuum oven at 60°C to obtain the purified POE-g-PHEMA product. Using an infrared calibration curve, the actual grafting yield was calculated to be 3.87%.

[0041] The present invention is further described in detail below in conjunction with the embodiments: Example 1

[0042] (1) Preparation of EuCl3 ethanol solution

[0043] 1 mmol (0.3519 g) of Eu2O3 was reacted with an appropriate amount of concentrated hydrochloric acid (about 1.6 ml) in a three-necked flask, and the mixture was stirred and evaporated to semi-dryness in an 80°C oil bath. 10 ml of ethanol was added to dissolve the EuCl3 in ethanol to obtain an ethanol solution.

[0044] (2) Preparation of EuMFT

[0045] Weigh 1 mmol (0.0861 g) of MAA, 2 mmol (0.297 ml) of FTFA, and 2 mmol (0.5566 g) of TPPO and dissolve them in 20 ml of ethanol. Add MAA dropwise to the EuCl3 ethanol solution, add an appropriate amount of triethylamine (approximately 2 ml), set the reaction temperature to 70°C, and the reaction time to 1 hour. Add FTFA for 1 hour, and then add the TPPO ethanol solution dropwise for 3 hours. The reaction produces a precipitate, which is washed three times with ethanol and dried under vacuum at 60°C for 12 hours to obtain the complex EuMFT.

[0046] (3) POE / POE- g - Preparation of PHEMA / EuMFT light-converting adhesive film

[0047] The POE particles were dried in an oven at 60 °C for more than 12 h, and then 6 wt% POE- g -PHEMA and 0.15 wt% EuMFT were blended with 2 wt% crosslinker TBEC, 0.1 wt% antioxidant, and 0.3 wt% UV absorber using an internal mixer. The internal mixer temperature was set to 80 ° C and the speed was set to 60 r / min. The resulting composite material was cross-linked and cured on a flat vulcanizer. The hot pressing temperature was set to 150 ° C, the hot pressing time was set to 10 min, and the cold pressing time was set to 5 min. 0.15 wt% POE / POE- g -PHEMA / EuMFT light-converting film.

[0048] Figure 1 The infrared spectrum of EuMFT is (c) the free ligand MAA at 2960 cm -1 and 2930 cm -1 The corresponding methyl and methylene stretching vibration peaks shifted to 2976 cm-1 after the complex was formed from (d). -1 and 2927 cm -1 , and located at 1636cm -1 The characteristic peak of carboxyl group near the complex is at 1537 cm -1The antisymmetric stretching vibration peak of carboxylic acid appears near the ligand, indicating that MAA participates in the coordination. (b) The carbonyl stretching vibration peak of the free ligand FTFA appears at 1620 cm -1 , when forming complexes with rare earth ions, it shifts to 1627 cm -1 Nearby, in rare earth complexes, at 1305 cm -1 、1184 cm -1 、1135 cm -1 The stretching vibration peak of -CF3 appears at 1121 cm, which shows that FTFA is bidentately coordinated with the rare earth ion. In addition, the P=O stretching absorption vibration of the free ligand TPPO (a) appears at 1121 cm -1 After coordination, the spectral band blue-shifted to 1096 cm -1 In the complex spectrum, 600-750 cm -1 The vibration peak corresponds to the out-of-plane bending vibration of CH in the TPPO aromatic ring, indicating that TPPO participates in the coordination. In the low-frequency region, the complex band is at 542 cm -1 An absorption peak appears near the surface of the nanostructured carbon monoxide (C2O) and is the CO-Eu coupled vibration absorption peak, indicating the synthesis of the complex EuMFT.

[0049] Figure 2 The UV absorption spectra of the ligand and the complex EuMFT are shown in Figure 2. The MAA solution has a strong absorption near 222 nm, which corresponds to the π→π * The FTFA solution has strong absorption mainly around 276 nm and 346 nm, corresponding to the π→π transition of the ligand. * Transition and n→π * In addition to strong absorption near 209 nm and 223 nm, TPPO solution also has obvious absorption at 265 nm and 272 nm, corresponding to the π→π transition of the ligand, respectively. * Transition and n→π * The EuMFT solution exhibits a sharp absorption peak at 212 nm, primarily derived from the characteristic absorption peak of the ligand MAA (222 nm). Larger absorption peaks are observed near 275 nm and 343 nm, primarily derived from the characteristic absorption peaks of the ligand FTFA (276 nm and 346 nm). Furthermore, sharper absorption peaks are observed near 207 nm and 209 nm, primarily derived from the characteristic absorption peaks of the ligand TPPO (209 nm and 223 nm), indicating that FTFA, MAA, and TPPO participate in the coordination.

[0050] Figure 3 The fluorescence spectra of the complex EuMFT in the embodiment and the complexes in comparative examples 3-6 are shown. 3+The emission peak spectrum consists of five peaks near 578, 592, 612, 652 and 702 nm, attributed to 5 D0→ 7 F J (J = 0 → 4) conversion emission. The characteristic emission intensity corresponding to 612 nm shows that the complex EuMFT has a strong fluorescence effect.

[0051] It can be seen from Table 1 that the crosslinking degree of the light-converting adhesive film prepared in Example 1 is 88.6%.

[0052] Table 2 shows that the tensile strength of the light-converting adhesive film prepared in Example 1 is 18.5 MPa, the elongation at break is 1424%, and the peel strength is 22.9 N / cm.

[0053] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back sheet from the inside out to form the light conversion film in Example 1 show a cell efficiency of 13.14%. Example 2

[0054] (1) Preparation of EuCl3 ethanol solution is the same as in Example 1

[0055] (2) Preparation of EuMFT is the same as in Example 1

[0056] (3) POE / POE- g -PHEMA / EuMFT light conversion film

[0057] The POE particles were dried in an oven at 60 °C for more than 12 h, and then 6 wt% POE- g -PHEMA and 0.30 wt% EuMFT were melt blended with 2 wt% crosslinker TBEC, 0.1 wt% antioxidant, and 0.3 wt% UV absorber using an internal mixer. The internal mixer temperature was set to 80 ° C and the speed was set to 60 r / min. The resulting composite material was cross-linked and cured on a flat vulcanizer. The hot pressing temperature was set to 150 ° C, the hot pressing time was set to 10 min, and the cold pressing time was set to 5 min. 0.30 wt% POE / POE- g -PHEMA / EuMFT light-converting film.

[0058] It can be seen from Table 1 that the crosslinking degree of the light-converting adhesive film prepared in Example 2 is 89.3%.

[0059] Table 2 shows that the tensile strength of the light-converting adhesive film prepared in Example 2 is 20.9 MPa, the elongation at break is 1382%, and the peel strength is 25.2 N / cm.

[0060] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back sheet from the inside out to form the light conversion film in Example 2 show a cell efficiency of 13.27%. Example 3

[0061] (1) Preparation of EuCl3 ethanol solution is the same as in Example 1

[0062] (2) Preparation of EuMFT is the same as in Example 1

[0063] (3) POE / POE- g -PHEMA / EuMFT light conversion film

[0064] The POE particles were dried in an oven at 60 °C for more than 12 h, and then 6 wt% POE- g -PHEMA and 0.45 wt% EuMFT were melt blended with 2 wt% crosslinker TBEC, 0.1 wt% antioxidant, and 0.3 wt% UV absorber using an internal mixer. The internal mixer temperature was set to 80 ° C and the speed was set to 60 r / min. The obtained composite material was cross-linked and cured on a flat vulcanizer. The hot pressing temperature was set to 150 ° C, the hot pressing time was set to 10 min, and the cold pressing time was set to 5 min. 0.45 wt% POE / POE- g -PHEMA / EuMFT light-converting film.

[0065] It can be seen from Table 1 that the crosslinking degree of the light-converting adhesive film prepared in Example 3 is 90.8%.

[0066] Table 2 shows that the tensile strength of the light-converting adhesive film prepared in Example 3 is 22.7 MPa, the elongation at break is 1214%, and the peel strength is 28.4 N / cm.

[0067] Table 3 shows that the cell JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back sheet from the inside out to form the light conversion film in Example 3 show a cell efficiency of 13.30%. Example 4

[0068] (1) Preparation of EuCl3 ethanol solution is the same as in Example 1

[0069] (2) Preparation of EuMFT is the same as in Example 1

[0070] (3) POE / POE- g -PHEMA / EuMFT light conversion film

[0071] The POE particles were dried in an oven at 60 °C for more than 12 h, and then 6 wt% of POE- g -PHEMA and 0.60 wt% EuMFT were melt blended with 2 wt% crosslinker TBEC, 0.1 wt% antioxidant, and 0.3 wt% UV absorber using an internal mixer. The internal mixer temperature was set to 80 ° C and the speed was set to 60 r / min. The obtained composite material was cross-linked and cured on a flat vulcanizer. The hot pressing temperature was set to 150 ° C, the hot pressing time was set to 10 min, and the cold pressing time was set to 5 min. 0.60 wt% POE / POE- g -PHEMA / EuMFT light-converting film.

[0072] It can be seen from Table 1 that the crosslinking degree of the light-converting adhesive film prepared in Example 4 is 91.7%.

[0073] Table 2 shows that the tensile strength of the light-converting adhesive film prepared in Example 4 is 23.4 MPa, the elongation at break is 1174%, and the peel strength is 33.8 N / cm.

[0074] Table 3 shows that the cell JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back sheet from the inside out to form the light conversion film in Example 4 show a cell efficiency of 14.08%. Comparative Example 1

[0075] The difference between Comparative Example 1 and Example 1 is that EuMFT and modifier POE- g -PHEMA, to prepare POE film.

[0076] It can be seen from Table 1 that the crosslinking degree of the film prepared in Comparative Example 1 is 89.9%.

[0077] Table 2 shows that the tensile strength of the film prepared in Comparative Example 1 is 15.9 MPa, the elongation at break is 1511%, and the peel strength is 12.9 N / cm.

[0078] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the film, the glass and the back plate from the inside out to form the film in Comparative Example 1 show a cell efficiency of 12.95%. Comparative Example 2

[0079] The difference between Comparative Example 2 and Example 1 is that no EuMFT was added in Comparative Example 2, and POE / POE- g -PHEMA film.

[0080] It can be seen from Table 1 that the crosslinking degree of the film prepared in Comparative Example 2 is 86.8%.

[0081] Table 2 shows that the tensile strength of the film prepared in Comparative Example 2 is 16.4 MPa, the elongation at break is 1629%, and the peel strength is 18.7 N / cm.

[0082] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the film, the glass and the back plate from the inside out to form the film in Comparative Example 2 show a cell efficiency of 12.99%. Comparative Example 3

[0083] (1) Preparation of EuCl3 ethanol solution is the same as in Example 1

[0084] (2) Preparation of Eu(FTFA)3(TPPO)2 (EuFT)

[0085] Weigh 3 mmol (0.445 ml) of FTFA and 2 mmol (0.5566 g) of TPPO and dissolve them in 20 ml of ethanol. Stir at 60°C for 30 minutes, then dropwise add EuCl₃ ethanol solution and a small amount of triethylamine (approximately 2 ml). Adjust the pH to 7, set the reaction temperature to 70°C, and react for 3 hours. Once the reaction is complete, wash with deionized water, centrifuge, and dry to obtain pale yellow EuFT. Its structural formula is as follows:

[0086]

[0087] (3) POE / POE- g - Preparation of PHEMA / EuFT light-converting adhesive film

[0088] EuFT was used to replace the EuMFT containing active double bonds in Example 1 to prepare 0.15 wt% POE / POE- g -PHEMA / EuFT light-converting film.

[0089] It can be seen from Table 1 that the crosslinking degree of the light-converting adhesive film prepared in Comparative Example 3 is 86.3%.

[0090] Table 2 shows that the tensile strength of the light-converting adhesive film prepared in Comparative Example 3 is 23.1 MPa, the elongation at break is 1057%, and the peel strength is 22.6 N / cm.

[0091] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back plate from the inside out to form the light conversion film in Comparative Example 3 show a cell efficiency of 13.33%. Comparative Example 4

[0092] (1) Preparation of EuCl3 ethanol solution is the same as in Example 1

[0093] (2) Preparation of Eu(DMPA)3Phen (EuDP)

[0094] Weigh 3 mmol (0.4024 g) of 2,2-dihydroxymethylpropionic acid (DMPA) and 1 mmol (0.1982 g) of 1,10-phenanthroline (Phen) and dissolve each in 10 ml of ethanol. Add the DMPA ethanol solution dropwise to the EuCl3 ethanol solution and allow to react for 10 minutes. Add an appropriate amount of triethylamine (approximately 2 ml) to adjust the pH to approximately 7. After 20 minutes of reaction, slowly add the Phen ethanol solution and allow to react for 3 hours, producing a white precipitate. This precipitate is then centrifuged, washed three times with ethanol, and dried to yield the complex EuDP. Its structural formula is as follows:

[0095]

[0096] (3) POE / POE- g -Preparation of PHEMA / EuDP light-converting adhesive film

[0097] EuDP was used to replace the EuMFT containing active double bonds in Example 1 to prepare 0.15 wt% POE / POE- g -PHEMA / EuDP light conversion film.

[0098] It can be seen from Table 1 that the crosslinking degree of the light-converting adhesive film prepared in Comparative Example 4 is 86.5%.

[0099] From Table 2, it can be seen that the tensile strength of the light-converting adhesive film prepared in Comparative Example 4 is 17.1 MPa, the elongation at break is 1564%, and the peel strength is 20.1 N / cm.

[0100] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back plate from the inside out to form the light conversion film in Comparative Example 4 show a cell efficiency of 13.05%. Comparative Example 5

[0101] (1) Preparation of EuCl3 ethanol solution is the same as in Example 1

[0102] (2) Preparation of Eu(OXA)3Phen (EuOP)

[0103] Dissolve 3 mmol (0.4984 g) of phthalic acid (OXA) in 25 ml of ethanol and 1 mmol (0.1982 g) of phenanthene in 10 ml of ethanol. Adjust the temperature to 60°C and drip the OXA ethanol solution into the EuCl3 ethanol solution for 10 minutes. Add an appropriate amount of triethylamine (approximately 2 ml) to adjust the pH to approximately 7. After 20 minutes of reaction, drip the phenanthene ethanol solution and continue the reaction for 3 hours to produce a white precipitate. Centrifuge, wash three times with ethanol, and dry to obtain the complex EuOP. Its structural formula is as follows:

[0104]

[0105] (3) POE / POE- g - Preparation of PHEMA / EuOP light-converting adhesive film

[0106] EuOP was used to replace the EuMFT containing active double bonds in Example 1 to prepare 0.15 wt% POE / POE- g -PHEMA / EuOP light conversion film.

[0107] It can be seen from Table 1 that the crosslinking degree of the light-converting adhesive film prepared in Comparative Example 5 is 86.2%.

[0108] Table 2 shows that the tensile strength of the light-converting adhesive film prepared in Comparative Example 5 is 16.8 MPa, the elongation at break is 1596%, and the peel strength is 19.8 N / cm.

[0109] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back plate from the inside out to form the light conversion film in Comparative Example 5 show a cell efficiency of 13.03%. Comparative Example 6

[0110] (1) Preparation of EuCl3 ethanol solution is the same as in Example 1

[0111] (2) Preparation of Eu(DBM)3TPPO2(EuDT)

[0112] Dissolve 3 mmol (0.6728 g) of dibenzoylmethane (DBM) and 2 mmol (0.5566 g) of TPPO in 10 ml of ethanol. Add the DBM ethanol solution to the EuCl3 ethanol solution and drip into the EuCl3 ethanol solution. Let it react for 10 minutes. Adjust the pH to approximately 7 with triethylamine (approximately 2 ml). After 20 minutes of reaction, slowly add the TPPO ethanol solution and let it react for 3 hours to produce a white precipitate. Centrifuge, wash three times with ethanol, and dry to obtain the complex EuDP. Its structural formula is as follows:

[0113]

[0114] (3) POE / POE- g -Preparation of PHEMA / EuDT light-converting adhesive film

[0115] EuDT was used to replace the EuMFT containing active double bonds of the present invention to prepare 0.15 wt% POE / POE- g -PHEMA / EuDT light-converting film.

[0116] It can be seen from Table 1 that the crosslinking degree of the film prepared in Comparative Example 6 is 86.9%.

[0117] It can be seen from Table 2 that the tensile strength of the film prepared in Comparative Example 6 is 17.4 MPa, the elongation at break is 1532%, and the peel strength is 20.5 N / cm.

[0118] Table 3 shows that the JV characteristic parameters of the cell prepared by laminating the crystalline silicon solar cell, the light conversion film, the glass and the back plate from the inside out to form the light conversion film in Comparative Example 6 show a cell efficiency of 13.06%.

[0119] Table 1 shows the crosslinking degree of POE film

[0120] .

[0121] As can be seen from the Examples and Comparative Example 2 in Table 1, the degree of crosslinking of the film increases with increasing EuMFT content, and the active double bonds of EuMFT participate in the crosslinking reaction during curing. Comparative Examples 2-6 and Example 1 show that small molecule complexes without double bonds have little effect on the degree of crosslinking of the film during curing.

[0122] Table 2 shows the mechanical properties of POE film

[0123] .

[0124] From Comparative Examples 1 and 2 in Table 2, it can be seen that the modifier POE- g-The introduction of PHEMA increases the tensile strength and elongation at break, playing a toughening role. It can be seen from Examples 1-4 that with the increase of EuMFT content, the tensile strength of the light-converting film increases significantly and the elongation at break decreases. It can be seen that the chemical bond generated by EuMFT and the POE matrix during cross-linking significantly enhances the bonding force, and the strong polar complex and the hydroxyl groups on the surface of the encapsulated glass produce chemical bonds during cross-linking, further improving the peel strength and significantly improving the bonding performance. In Comparative Examples 4-6, the polarity of the complex produces hydrogen bonds with the matrix, which increases the tensile strength, decreases the elongation at break, and increases the peel strength, but the degree of change is not large. In Comparative Example 3, the strong polarity of the complex produces a strong force with the matrix, which significantly increases the tensile strength and peel strength of the film, but is still less than the tensile strength and peel strength of the film in Example 4. This shows that EuMFT can effectively improve the bonding force of the matrix.

[0125] Table 3 JV characteristic parameters of batteries prepared with POE film

[0126] .

[0127] As shown in Examples 1-4 in Table 3, cell efficiency increases with increasing EuMFT content. Comparative Examples 2 and 4 show that the photoelectric conversion efficiency increases from 12.99% to 14.08%. The presence of EuMFT-doped light-converting adhesive film effectively improves the cell's photoelectric conversion efficiency. Comparative Examples 3-6 show that doping POE films with other complexes also improves cell conversion efficiency, but to a lesser extent than with EuMFT.

[0128] The film was subjected to UV aging and long-term storage to test its fluorescence effect and investigate its permanent light conversion and UV resistance. The film was placed in a UV aging chamber, irradiated with UV light of 0.87 W / m² in the wavelength range of 280 nm to 400 nm. The irradiation in the 280 nm to 320 nm band accounted for (3-10)% of the total irradiation. The film was irradiated for 500 h at a temperature of 60°C ± 5°C. After the film was removed and stored for a period of time, its light conversion performance was tested. The results are shown in Table 4.

[0129] Table 4 Fluorescence intensity of POE film after UV aging

[0130] .

[0131] As can be seen from the examples, the excitation and emission peak intensities before and after aging remain essentially unchanged, and the fluorescence intensity is essentially unaffected by UV aging and prolonged storage. This indicates that the EuMFT complex has good compatibility with the POE matrix and will not migrate to the surface of the matrix during use, causing failure. It exhibits permanent light conversion and good UV resistance. However, the light-converting film in the comparative example exhibits a halving of its excitation and emission peak intensities after aging and prolonged storage, significantly reducing its fluorescence performance. This is significantly affected by the external environment, likely due to migration or failure of the small molecule light-converting agent during aging. It lacks permanent light conversion and its UV resistance is far inferior to that of the POE / POE- g -PHEMA / EuMFT light-converting film.

[0132] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A POE light-converting film, characterized in that: The POE light-converting adhesive film contains a rare earth europium complex, POE, and additives; the additives include one or more of a modifier, a cross-linking agent, an antioxidant, and an ultraviolet absorber; the rare earth europium complex uses rare earth europium as a central ion, methacrylic acid (MAA) and 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione (FTFA) as ligands, and triphenylphosphine oxide (TPPO) as a co-ligand; the rare earth europium complex has a reactive double bond, and its structural formula is as follows: 。 2. The POE light-converting adhesive film according to claim 1, characterized in that: The preparation method of the rare earth europium complex specifically comprises the following steps: providing EuCl3 ethanol solution, MAA ethanol solution, FTFA ethanol solution and TPPO ethanol solution respectively; Preparation of rare earth europium fluorescent complex: MAA ethanol solution is added dropwise to EuCl3 ethanol solution, pH is adjusted to 6-7 by adding pH adjuster, and fully reacted; then FTFA ethanol solution is added dropwise and fully reacted; finally, TPPO ethanol solution is added dropwise to react to produce precipitate; the precipitate is collected by centrifugation, washed, and dried to obtain rare earth europium complex Eu(MMA)(FTFA)2TPPO2, labeled as EuMFT.

3. The POE light-converting adhesive film according to claim 2, characterized in that: The molar ratio of EuCl3, MAA, FTFA and TPPO is 1:1:2:

2.

4. The POE light-converting adhesive film according to claim 2, characterized in that: The pH regulator is triethylamine.

5. The POE light-converting adhesive film according to claim 2, characterized in that: The reaction temperature is 60-80°C.

6. The POE light-converting adhesive film according to claim 1, characterized in that: The composition by weight percentage is: Rare earth europium complex 0.15-0.6 wt% Modifier 4-12 wt% Crosslinking agent 1-3 wt% Antioxidant 0.05-5 wt% UV absorber 0.03-4 wt% POE margin.

7. The POE light-converting adhesive film according to claim 6, characterized in that: The modifier is maleic anhydride, acrylic acid, glycidyl methacrylate, citric acid, itaconic acid, palmitic acid, stearic acid, PS- g -PA、PS- b -PA、MA- g -LDPE、MA- g -EVA, ABS- g -MAH、POE- g -PHEMA、POE- g -MAH、POE- g -NH2, POE-g-GMA or more; The crosslinking agent is one or more of dicumyl peroxide (DCP), benzoyl peroxide (BPO), di-tert-butyl peroxide (DTBP), diethylenetriamine (DTA), tert-butyl peroxy-2-ethylhexyl ester (TBEC), 2,5-dimethyl-2,5-di-tert-butyl peroxyhexane (bis-25), ethylene glycol diacetate (EGDE), ethylene glycol diacrylate (EGDA), diisopropylbenzene hydroperoxide (DBHP), and N,N-methylenebisacrylamide (MBA); The antioxidant is one or more of aromatic amine antioxidants, hindered phenol antioxidants, and auxiliary antioxidants; The ultraviolet absorber is one or more of the following: light stabilizer GW-540, light stabilizer 744, light stabilizer HPT, ultraviolet absorber RMB, ultraviolet absorber UVP-327, ultraviolet absorber UV-531, ultraviolet absorber UV-9, and ultraviolet absorber UV-P.

8. A method for preparing the POE light-converting adhesive film according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: mixing pre-dried POE particles with rare earth europium complex and other additives in an internal mixer, and then laminating and curing on a flat vulcanizing machine to prepare POE / POE- g -PHEMA / EuMFT light-converting film.

9. The method for preparing the POE light-converting adhesive film according to claim 8, wherein: The temperature of the internal mixer is set to 80-90 °C, and the speed is set to 40-60 r / min; the hot pressing temperature of the lamination curing is set to 150-160 °C, the hot pressing time is set to 10-15 min, and the cold pressing time is set to 5-10 min.

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