A photovoltaic light conversion adhesive film with up-down multifunctional conversion and a preparation method thereof

Abstract

This invention discloses a photovoltaic light-converting film with multifunctional upper and lower conversion and its preparation method, comprising a stop layer, a light conversion layer, and a scattering layer, wherein the thickness ratio of the stop layer, the light conversion layer, and the scattering layer is 1:(0.2~1):(0.2~0.5); the stop layer includes a UVB absorber, the light conversion layer includes a light-converting masterbatch, and the scattering layer includes a refractive masterbatch; the light-converting masterbatch is obtained by granulation of a light-converting agent and blank particles, wherein the blank particles are EVA particles or POE particles; the light-converting agent includes an upper light-converting agent and a lower light-converting agent, wherein the upper light-converting agent is an inorganic rare earth nanomaterial, and the lower light-converting agent is an organic aggregation-induced emission type triazine-based star molecule with a particle size of 30-50 nm; the content of the upper conversion agent in the light-converting masterbatch is 0.1%-10%, and the content of the lower conversion agent in the light-converting masterbatch is 0.1%-10%.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic light conversion adhesive film technology, specifically relating to a photovoltaic light conversion adhesive film with multi-functional up-down conversion and its preparation method. Background Technology

[0002] The ultraviolet frequencies that have a significant impact on solar cells can be divided into two types: UVA (ultraviolet A, wavelength 380nm-320nm, photon energy 3.1-3.9eV) and UVB (wavelength 320nm-280nm, photon energy 3.9-4.4eV). The photon energy at 320nm is 3.88eV, at 360nm it is 3.45eV, at 380nm it is 3.26eV, and at 400nm it is 2.95eV. In TOPCon cells, Si-H bonds break above 3.5eV, and in HJT cells, Si-H bonds break above 2.9eV.

[0003] The solar spectrum is a broadband pattern ranging from 200 nm to 2500 nm. For crystalline silicon photovoltaic cells, due to their semiconductor bandgap of 1.1 eV, they can only respond to light waves in the 200 nm to 1200 nm range. For high-energy photons, such as ultraviolet and blue-green light, the absorption of one photon only produces one electron. Hole pairs and other energy are lost as heat through lattice resonance; light with wavelengths greater than 1200nm cannot be absorbed by crystalline silicon photovoltaic cells, resulting in the complete loss of this portion of solar energy. Calculations show that currently available crystalline silicon photovoltaic cells can effectively utilize approximately 486W / m of energy from the solar spectrum. 2 Of the energy that cannot be effectively utilized, 164 W / m can be used for upconversion (infrared light to visible light). 2 The portion that can be used for downconversion (ultraviolet to visible light) has 149W / m 2 .

[0004] Currently, increasing the power output of photovoltaic (PV) modules is quite difficult. Even a 0.2% increase in module power, combined with the economies of scale in the PV industry, is of considerable value. PV light conversion films, as an important component of PV modules, contribute significantly to improving module power. A common type of conventional PV light conversion film is the down-conversion film. Patent application CN116741866A discloses a composite film and PV module. The composite film includes a stop-off layer, a first isolation layer, and a down-conversion layer stacked sequentially. The stop-off layer contains a stop agent and is used to control the spectral irradiation range; the down-conversion layer is a film with down-conversion function, used to convert ultraviolet light to visible light; the first isolation layer prevents the stop-off layer and the down-conversion layer from merging. PV modules encapsulated with this composite film can maintain a high light conversion efficiency over a long period, maximizing the light conversion effect and significantly improving both module output power and reliability. However, in the existing technology, the application of upconversion materials in patent CN117229728A is relatively limited. At the same time, due to losses such as interface reflection, there is still room for improvement in the utilization rate of sunlight by photovoltaic light conversion films.

[0005] In patent CN118834620A, the existing method for obtaining a light-converting film converts short-wavelength ultraviolet light into visible light usable by photovoltaic modules, but does not address long-wavelength near-infrared light. However, in the solar spectrum, ultraviolet light accounts for only 5%, while near-infrared and infrared light account for as much as 49%. Furthermore, current light-converting agents mainly include inorganic agents, organic fluorescent pigments, and rare-earth organic complexes. However, inorganic agents have poor dispersibility in the film and low luminescence performance; organic fluorescent pigments, while exhibiting strong luminescence performance, have poor ultraviolet weather resistance; and rare-earth organic complexes have high initial brightness and good compatibility with the matrix material, but poor weather resistance and are prone to photodegradation under sunlight.

[0006] Currently used light-conversion films generally suffer from the following problems: 1) migration of the light-conversion aid leads to a decrease in light conversion function; 2) incomplete ultraviolet light conversion, with some ultraviolet light reaching the solar cell and causing damage; 3) the light-conversion agent is prone to failure, directly exposing the solar cell to the ultraviolet environment and damaging it. To address these problems, existing technologies include adding a stopper agent to the light-conversion film. The stopper agent and the light-conversion aid are used simultaneously; even if the light-conversion aid fails, the stopper agent can still protect the solar cell from ultraviolet damage. However, in this method, the stopper agent and the light-conversion aid interact, weakening the light conversion effect. Summary of the Invention

[0007] This invention provides a photovoltaic light conversion film with multi-functional up-down conversion and its preparation method, which at least solves the technical problem that the use of conventional stop agents and light conversion agents in combination reduces the light conversion efficiency of the film.

[0008] To achieve the above objectives, in a first aspect, the present invention provides a photovoltaic light-converting film with multifunctional up-and-down switching, comprising a cutoff layer, a light conversion layer, and a scattering layer, wherein the thickness ratio of the cutoff layer, the light conversion layer, and the scattering layer is 1:(0.2~1):(0.2~0.5). The cutoff layer includes a UVB absorber, the light conversion layer includes a light conversion masterbatch, and the scattering layer includes a refractive masterbatch. The light conversion masterbatch is obtained by granulation of a light conversion agent and blank particles, wherein the blank particles are EVA particles or POE particles. The light-converting agent includes an upper light-converting agent and a lower light-converting agent. The upper light-converting agent is an inorganic rare earth nanomaterial, and the lower light-converting agent is an organic aggregation-induced emission type triazine star molecule with a particle size of 30-50 nm. The upconversion agent is present in the masterbatch at a content of 0.1%-10%; The downconversion agent is present in the masterbatch at a content of 0.1%-10%.

[0009] Preferably, the mass ratio of the upper light-converting agent to the lower light-converting agent is (1~2):(1~3).

[0010] Preferably, the mass ratio of the upper light-converting agent to the lower light-converting agent is (1~2):1.

[0011] Preferably, the mass ratio of the upper light-converting agent to the lower light-converting agent is 1:(1~3).

[0012] Preferably, the inorganic rare earth nanomaterials are selected from Er 3+ Y2O3, Er 3+ ZrO2, Yb 3+ -Er 3+ ZrO2, Er 3+ YAlO3, Er 3+ -Yb 3+ Gd2O3, Er 3+ YF3, Yb 3+ -Er 3+ :NaYF4 or Er 3+ At least one of LaF3; the organic aggregation-induced emission triazine star molecule is TTPE-Tr.

[0013] Preferably, the UVB absorber is selected from at least one of diethylhexylbutamidotriazinone, 4-methylbenzyl camphor, humosasulfate, ethylhexyl salicylate, ethylhexyl methoxycinnamate, dimethyl PABA ethylhexyl ester, ethylhexyl triazinone, and phenylbenzimidazole sulfonic acid.

[0014] Preferably, the refractive masterbatch is prepared by mixing high refractive index particles with blank particles; the high refractive index particles are selected from at least one of cadmium sulfide, zinc sulfide, cadmium selenide, cadmium telluride, titanium dioxide, and zirconium dioxide.

[0015] Preferably, the light conversion layer comprises the following components: 100 parts of base resin, 0.01-0.5 parts of phototransfer masterbatch, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant.

[0016] Preferably, the stop layer comprises the following components: 100 parts of matrix resin, 0.05-0.5 parts of UVB absorber, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant.

[0017] Preferably, the scattering layer comprises the following components: 100 parts of matrix resin, 0.01-0.5 parts of refractive masterbatch, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant.

[0018] Preferably, the crosslinking agent is selected from at least one of 2-ethylhexyl carbonate peroxide, tert-butyl peroxycarbonate-2-ethylhexyl, 1,1-bis-tert-butyl peroxide-3,3,5-trimethylcyclohexane, tert-butyl peroxide-3,5,5-trimethylhexanoate, and benzoyl peroxide.

[0019] Preferably, the crosslinking agent is selected from at least one of trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, triallyl isocyanurate, tetramethyltetravinylcyclotetrasiloxane, 4-acryloylmorpholine, 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate, neopentyl glycol (2)PO diacrylate, polyethylene glycol 200 diacrylate, EO (3) trimethylolpropane triacrylate, and 3(propoxy)propanetriol triacrylate.

[0020] Preferably, the coupling agent is selected from at least one of vinyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, aminopropyltrimethoxysilane, bis(3-triethoxysilylpropyl)amine, N,N-dimethyl-3-aminopropyltrimethoxysilane, 1,3,5-tris(trimethoxysilylpropyl)isocyanate, n-dodecyltrimethoxysilane, n-octyltrimethoxysilane, cyclohexyltrimethoxysilane, and 1,3,5-tris(trimethoxysilylpropyl)isocyanate.

[0021] Preferably, the light stabilizer is selected from at least one of bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, bis(2,2,6,6-tetramethylpiperidinyl) sebacate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, (1-octoxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate / mono(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, and poly-{[6-[(1,1,3,3,-tetramethylbutyl)-amino]1,3,5,-triazine-2,4-diyl][(2,2,6,6-tetramethylpiperidinyl)-imino]}.

[0022] Preferably, the antioxidant is selected from at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 3,5-di-tert-butyl-4-hydroxybenzyl diethylphosphonate, and 4,4'-p-isopropyl diphenyl C12-15-ol phosphite.

[0023] Secondly, the present invention provides a method for preparing a photovoltaic photoconverter film with up-down multi-functional conversion, comprising the following steps: (1) Preparation of the cutoff layer: After the UVB absorber, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly, the cutoff layer is prepared by casting film process; the temperature of casting film process is 88~93℃ and the thickness is 0.1~0.2mm; (2) Preparation of light conversion layer: The upper light conversion agent, the lower light conversion agent and blank particles are mixed, melted, extruded and granulated to obtain light conversion masterbatch. The granulation temperature is 85~100℃. The light conversion masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly and then the light conversion layer is obtained by casting film process. The casting film process temperature is 88~93℃ and the thickness is 0.1~0.2mm. The mixing speed for even mixing in the preparation of light conversion layer is 400~850rpm. (3) Preparation of scattering layer: High refractive index particles are mixed with blank particles, and after melting, extrusion and granulation, a refractive masterbatch is obtained. The granulation temperature is 85~100℃. The refractive masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly and then the scattering layer is obtained by casting film process. The casting film process temperature is 88~93℃ and the thickness is 0.1~0.2mm.

[0024] Preferably, in step (2), the mixing speed for uniform mixing during the preparation of the light conversion layer is 700~850 rpm.

[0025] The beneficial effects of this invention are as follows: This invention simultaneously adds both an upper and lower light-converting agent, enabling optimized utilization of sunlight. Furthermore, the lower light-converting agent used in this invention is an organic aggregation-induced emission material, exhibiting good compatibility with the film matrix material, high light conversion efficiency, and high photostability. The upper light-converting agent uses an inorganic rare-earth nano-light-converting agent, which boasts high luminescence efficiency and a nano-sized particle size, thus having no impact on the film's transmittance. The light-converting masterbatch employs a proportional blending of organic and inorganic light-converting agents, combining their advantages to maximize light conversion efficiency and stability. Aggregation-induced emission materials are novel organic light-converting materials that solve the problem of fluorescence quenching at high concentrations in traditional organic dyes. They exhibit stronger luminescence in the aggregated state and, when used in combination with polymers and other carriers, demonstrate excellent light conversion effects and temperature resistance. Containing aromatic or heterocyclic structures, they can achieve highly efficient light conversion in specific matrices through molecular design. The downconversion agent in the light conversion layer is an organic aggregation-induced emission type triazine star molecule with a particle size of 30-50nm. The moderate particle size makes it easier to disperse evenly in the film matrix, avoiding agglomeration and ensuring the uniformity and mechanical properties of the film. It can also avoid problems such as light scattering caused by large particle size reducing the effective transmission distance of light in the film and affecting the overall photoelectric conversion efficiency. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of the photovoltaic light-converting adhesive film provided in Embodiment 1 of the present invention.

[0028] Figure 2 This is a schematic diagram of the structure of the photovoltaic light-converting adhesive film provided in Comparative Example 1 of the present invention. Detailed Implementation

[0029] In this invention, unless otherwise stated, directional terms such as "up," "down," "left," and "right" are generally understood in conjunction with the accompanying drawings and the directions shown in actual applications.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0032] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. The terms "optional" and "discretionary" mean that they may or may not be included (or may or may not be present).

[0033] To address the aforementioned problems, this invention provides a photovoltaic light-converting film with multi-functional up-and-down switching capabilities, such as... Figure 1 As shown, the light-converting film includes a cutoff layer, a light conversion layer, and a scattering layer. The thickness ratio of the cutoff layer, the light conversion layer, and the scattering layer is 1:(0.2~1):(0.2~0.5). It can be one or any two of the following: 1:0.2:0.2, 1:0.3:0.2, 1:0.4:0.2, 1:0.5:0.2, 1:0.2:0.3, 1:0.2:0.4, 1:0.2:0.5. The three-layer integrated light-converting film achieves a dual objective: it provides precise protection through the cutoff layer and converts the originally harmful energy into gain through the light conversion layer, thus achieving a unity of protection and efficiency enhancement.

[0034] The aforementioned cutoff layer includes a UVB absorber, the aforementioned light conversion layer includes a light conversion masterbatch, and the aforementioned scattering layer includes a refractive masterbatch. The light conversion masterbatch is obtained by granulation of the light conversion agent and blank particles, wherein the blank particles are EVA particles or POE particles. When the masterbatch is mixed with EVA particles or POE particles, it is equivalent to secondary dispersion, which can ensure that the light conversion agent is evenly distributed in the final photovoltaic film. The aforementioned UVB absorber has high absorption intensity (transmittance <20) in the 280~320nm light wave range and high transmittance (>70%) in the 320~380nm light wave range. The combination of the UVB cutoff layer and the light conversion layer has no effect on the light conversion efficiency of the film. Adding a UVB absorber can reduce the amount of light conversion agent used and reduce the cost of the film.

[0035] The aforementioned light-converting agent includes an upper light-converting agent and a lower light-converting agent. The upper light-converting agent is an inorganic rare-earth nanomaterial, and the lower light-converting agent is an organic aggregation-induced emission type triazine-based star-shaped molecule with a particle size of 30-50 nm, which can be any value within the range of 30 nm, 35 nm, 40 nm, 45 nm, and 50 nm. A transparent inorganic filler with a high refractive index is added to the film layer to work together to maximize the refractive index of the film, reduce light loss at the interface, and improve the initial power of the component. If the particle size is too small (e.g., less than 10 nm), the intermolecular interaction is weak, which may lead to insufficient light absorption cross-section, affecting the light energy capture efficiency. In the high-shear, high-temperature environment of melt blending, extremely small particles, due to their extremely high Brownian motion kinetic energy and surface activity, are very likely to break through the coupling agent coating layer and undergo hard aggregation, forming secondary particles >100 nm, which become light scattering centers and sources of mechanical defects. If the particle size is too large (e.g., more than 100 nm), it will induce light scattering, reduce the effective transmission distance of light in the film, and affect the overall photoelectric conversion efficiency. The light conversion layer is only 0.1~0.2 mm thick, and the particle size of 30~50 nm is about one ten-thousandth to three ten-thousandths of the layer thickness. The light field is continuously distributed within the layer, avoiding "fluorescence quenching hotspots" (where excessively high local concentrations cause energy backhaul or self-absorption) caused by uneven local concentration.

[0036] The content of the above-mentioned upconversion agent in the optical conversion masterbatch is 0.1%-10%, and can be one or any two of the following values: 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%. The content of the aforementioned downconversion agent in the light conversion masterbatch is 0.1%-10%, and can be one or any two of the following values: 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%. Traditional organic dyes are prone to "aggregation-induced quenching (ACQ)" at high concentrations, meaning that the molecules aggregate together and stop emitting light, which limits the amount that can be added. The downconversion agent is an organic aggregation-induced luminescence type triazine star molecule with "aggregation-induced luminescence" characteristics, such as becoming brighter the more aggregated it is. This allows for the addition of higher concentrations of the light conversion agent to the film, thereby compensating for the shortcoming that the single-molecule conversion efficiency of organic materials may be lower than that of rare earth materials. By adding a higher amount, a better effect of improving the luminescence effect can be achieved.

[0037] In this invention, organic and inorganic light-converting agents are coated onto a light-converting agent carrier in an optimal mixing ratio to prepare a light-converting agent masterbatch. The masterbatch is then dispersed in a membrane matrix to form a light-converting membrane. Coating the light-converting agent onto the carrier effectively prevents its oxidation and deliquescence. Furthermore, it allows for pre-dispersion of the agent, improving its dispersibility in the membrane matrix. Simultaneously, the complementary properties of the organic and inorganic light-converting agents enhance the weather resistance and service life of the light-converting membrane.

[0038] Optionally, in one embodiment, the mass ratio of the upper light-converting agent to the lower light-converting agent is (1~2):(1~3). By optimizing the ratio of inorganic upper light-converting agent to organic lower light-converting agent added to the masterbatch and optimizing the mixing speed, the dispersibility and stability of the light-converting agent in the film matrix are greatly improved, the light conversion performance is stable, and the adverse effects of ultraviolet and near-infrared light on the module are reduced, thus extending the service life of the module.

[0039] Optionally, in one embodiment, the mass ratio of the upper light-converting agent to the lower light-converting agent is (1~2):1, which can be one of 1:1, 2:1 or any two of them.

[0040] Optionally, in one embodiment, the mass ratio of the upper light-converting agent to the lower light-converting agent is 1:(1~3), which can be one of 1:1, 1:2, 1:3 or any two of them.

[0041] The simultaneous addition of an upper and lower light-converting agent in this invention enables better utilization of sunlight. Furthermore, the lower light-converting agent used in this invention is an organic aggregation-induced emission material, which has good compatibility with the film substrate material, high light conversion efficiency, and high photostability. The upper light-converting agent uses rare-earth nano-light-converting agents, which have high luminous efficiency and a nano-sized particle size, thus having no impact on the film transmittance.

[0042] Optionally, in one embodiment, the above-mentioned inorganic rare earth nanomaterials are selected from Er 3+ Y2O3, Er 3+ ZrO2, Yb 3 + -Er 3+ ZrO2, Er 3+ YAlO3, Er 3+ -Yb 3+ Gd2O3, Er 3+ YF3, Yb 3+ -Er 3+ :NaYF4 or Er 3+ At least one of LaF3; the aforementioned organic aggregation-induced emission triazine star-shaped molecule is TTPE-Tr. Combining aggregation-induced emission (AIE) agents such as triazine star-shaped molecules (TTPE-Tr) with inorganic rare earth agents represents a promising organic-inorganic hybrid strategy in photovoltaic films (such as EVA or POE films). This combination is not a simple physical mixture, but rather based on the complementarity of the two in terms of spectral response, luminescence mechanism, and stability.

[0043] The advantages of TTPE-Tr aggregation-induced emission conversion agent and inorganic rare earth conversion agent in photovoltaic film applications are as follows: Complementary spectral coverage: Inorganic rare earth conversion agents excel at absorbing specific wavelengths of ultraviolet light and emitting narrow-band red or green light, exhibiting high and stable conversion efficiency, but their absorption bands are typically narrow (mainly due to ff transitions). TTPE-Tr (AIE molecule), as an organic molecule, typically possesses a broad ultraviolet absorption band, and its emission wavelength can be adjusted through chemical modification. The combination of the two can create a synergistic effect of broad-spectrum absorption and precise emission. TTPE-Tr can absorb the weakly absorbed ultraviolet bands of rare earth ions, converting them into visible light, or transfer energy to inorganic rare earth ions through an energy transfer mechanism, enhancing the luminescence intensity of inorganic rare earth ions (i.e., the "antenna effect"). Complementary aggregated emission mechanism: Traditional organic dyes are prone to aggregation at high concentrations, leading to quenching (ACQ), meaning the molecules aggregate and cease luminescence, limiting the amount that can be added. TTPE-Tr (AIE) exhibits aggregation-induced emission properties, becoming brighter with increased aggregation. In the high-viscosity, solid matrix of the film, AIE molecules tend to aggregate, which maximizes their luminescence efficiency. AIE molecules address the issue of insufficient brightness in films due to excessive organic light-converting agents, allowing for the addition of higher concentrations of light-converting agents to compensate for the lower single-molecule conversion efficiency of organic materials compared to rare-earth materials.

[0044] In this invention, the inorganic rare earth light-converting agent alone exhibits high light conversion efficiency, but is limited by its small absorption cross-section and narrow spectral range (specific wavelength). It has excellent weather resistance / lifespan (weather resistance, high temperature resistance), but its processing performance is characterized by difficulty in dispersion and easy aggregation. The organic aggregation-induced emission type triazine star molecule alone has high initial light conversion efficiency and a wide spectral range, but is prone to drift, has poor weather resistance / lifespan (easily photobleached and degraded), and its processing performance is characterized by easy dispersion but easy migration. The combined use of TTPE-Tr's aggregation-induced emission light-converting agent and the inorganic rare earth light-converting agent results in extremely high light conversion efficiency. The high-concentration luminescence characteristics of the AIE molecule compensate for the shortcomings of rare earth... Overcoming the drawback of weak absorption, this system achieves synergistic effects, covering a wider ultraviolet band (280-400nm), converting more ineffective ultraviolet light into visible light (400-700nm) that can be absorbed by the battery, significantly improving weather resistance and lifespan. The chemical stability of rare earth ions provides skeletal support for the system, delaying the photoaging of organic AIE molecules. The rigid structure of AIE molecules themselves is generally more stable than that of traditional dyes, improving dispersion performance. AIE molecules are stable in the aggregated state and are not prone to phase separation. They are dispersed together with rare earth particles in the EVA / POE matrix, reducing the risk of crystal points or haze in the film.

[0045] The combination of TTPE-Tr and inorganic rare earth light-converting agents in this invention essentially utilizes the high-concentration luminescence advantage of AIE materials to compensate for the small absorption cross-section of rare earth materials, while simultaneously leveraging the ultra-high stability of rare earth materials to enhance the weather resistance of the organic system. This photovoltaic film modification achieves a balance of high efficiency, long lifespan, and low cost. When applied to photovoltaic modules, this film improves power generation gain (especially in the early morning, late evening, and on cloudy days). TTPE-Tr materials typically exhibit good response to weak and diffused light; combined with the efficient conversion of inorganic rare earths, it allows modules to more effectively utilize diffused ultraviolet light in low-light environments such as early morning, late evening, or cloudy days, thus extending the overall power generation duration. This further extends the module's lifespan, as the inorganic rare earth materials themselves are extremely stable and can maintain performance over a long period. The introduction of AIE molecules, which convert harmful ultraviolet light into useful light, reduces the aging and damage (yellowing) of the EVA / POE film matrix caused by ultraviolet light, thereby protecting the solar cells. Furthermore, it can further reduce costs. Although rare earth materials have good performance, they are expensive, while pure organic materials are inexpensive but have a short lifespan. By combining a small amount of rare earth with high-efficiency AIE, it is possible to reduce the amount of expensive rare earth materials used while maintaining high performance and long lifespan, thus optimizing the overall cost of the film.

[0046] Optionally, in one embodiment, the UVB absorber is selected from at least one of diethylhexylbutamidotriazinone, 4-methylbenzyl camphor, homosalate, ethylhexyl salicylate, ethylhexyl methoxycinnamate, dimethyl PABA ethylhexyl ester, ethylhexyl triazinone, and phenylbenzimidazole sulfonic acid; preferably, it is selected from diethylhexylbutamidotriazinone. Diethylhexylbutamidotriazinone has an extremely high extinction coefficient in the 280-310 nm UVB region, while its transmittance above 320 nm is >70%. This facilitates the almost unaffected penetration of light above 320 nm through the cutoff layer, where it is efficiently captured by TTPE-Tr for downconversion. Light below 320 nm is preferentially absorbed by the cutoff layer and converted into harmless heat energy, preventing it from reaching the light conversion layer, thus avoiding the influence of light below 320 nm on TTPE-Tr, etc.

[0047] Optionally, in one embodiment, the aforementioned refractive masterbatch is prepared by mixing high-refractive-index particles with blank particles; the high-refractive-index particles are selected from at least one of cadmium sulfide, zinc sulfide, cadmium selenide, cadmium telluride, titanium dioxide, and zirconium dioxide; wherein, zinc sulfide has a refractive index as high as 2.3~2.4 at 550nm light wavelength, which can effectively increase the refractive index of the masterbatch and the final film, enhance light scattering and path length, form a micro-nano refractive interface in the scattering layer, and further facilitate the extension of the transmission path of visible light after TTPE-Tr conversion within the component, thereby improving light energy utilization. High-refractive-index particles can promote the aggregation-induced emission effect of TTPE-Tr, maintain a highly efficient luminescent state, and assist TTPE-Tr in maintaining an ideal aggregation state in the masterbatch matrix, ensuring its high luminescence efficiency. The core advantage of TTPE-Tr is the aggregation-induced emission effect, that is, strong fluorescence is emitted when molecules aggregate due to restricted intramolecular rotation. High-refractive-index inorganic particles can act as "aggregation nuclei," guiding TTPE-Tr molecules to form ordered and uniform nano-aggregates around them through surface adsorption, rather than random stacking that leads to fluorescence quenching, thus stabilizing their efficient luminescence state.

[0048] Optionally, in one embodiment, the light conversion layer comprises the following components: The light conversion layer comprises 100 parts of matrix resin, 0.01-0.5 parts of light conversion masterbatch, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant. This composition significantly delays the yellowing and embrittlement of the film, ensuring stable light conversion efficiency throughout its entire lifespan (over 25 years), and preventing rapid power degradation of the module due to film aging. This composition endows the film with extremely high heat resistance, creep resistance, and mechanical strength. Good compatibility ensures uniform dispersion of light-converting particles within the film, preventing aggregation or precipitation over time, thus guaranteeing uniform optical performance.

[0049] Optionally, in one embodiment, the above-mentioned stop layer comprises the following components: 100 parts of matrix resin, 0.05-0.5 parts of UVB absorber, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant.

[0050] Optionally, in one embodiment, the scattering layer comprises the following components: The matrix resin comprises 100 parts, refractive masterbatch 0.01-0.5 parts, crosslinking agent 0.3-1 parts, co-crosslinking agent 0.2-0.8 parts, coupling agent 0.1-0.6 parts, light stabilizer 0.05-0.3 parts, and antioxidant 0.01-0.2 parts. The high refractive index particles in the resulting scattering layer form numerous tiny refractive interfaces within the resin matrix, causing multiple scattering of incident light. This significantly increases the light transmission path length within the module, enhances the probability of light absorption by the solar cell, and thus improves the short-circuit current.

[0051] Optionally, in one embodiment, the crosslinking agent is selected from at least one of 2-ethylhexyl carbonate tert-amyl peroxide, tert-butyl peroxycarbonate-2-ethylhexyl peroxide, 1,1-bis-tert-butyl peroxide-3,3,5-trimethylcyclohexane, tert-butyl peroxide-3,5,5-trimethylhexanoate, and benzoyl peroxide; wherein, 1,1-bis-tert-butyl peroxide-3,3,5-trimethylcyclohexane is the most stable of all organic peroxides, and does not decompose at high casting temperatures during preparation, thus avoiding free radical damage to the TTPE-Tr conjugated structure; during lamination, crosslinking forms a dense network, restricting intramolecular rotation of TTPE-Tr, enhancing its aggregation-induced emission (AIE) effect, while preventing migration and precipitation, and ensuring photoconversion stability.

[0052] Optionally, in one embodiment, the aforementioned crosslinking agent is selected from at least one of the following: trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, triallyl isocyanurate, tetramethyltetravinylcyclotetrasiloxane, 4-acryloylmorpholine, 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate, neopentyl glycol (2)PO diacrylate, polyethylene glycol 200 diacrylate, EO (3) trimethylolpropane triacrylate, and 3(propoxy)propaneglycerol triacrylate; wherein, triallyl isocyanurate has extremely high bond energy, improving the heat and weather resistance of the film, preventing TTPE-Tr migration and precipitation, and ensuring long-term light conversion stability. When used in conjunction with the crosslinking agent 1,1-di-tert-butylperoxide-3,3,5-trimethylcyclohexane, a dense three-dimensional crosslinked network is formed, restricting the intramolecular rotation of TTPE-Tr and enhancing its aggregation-induced light emission effect.

[0053] Optionally, in one embodiment, the coupling agent is selected from at least one of the following: vinyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, aminopropyltrimethoxysilane, bis(3-triethoxysilylpropyl)amine, N,N-dimethyl-3-aminopropyltrimethoxysilane, 1,3,5-tris(trimethoxysilylpropyl)isocyanate, n-dodecyltrimethoxysilane, n-octyltrimethoxysilane, cyclohexyltrimethoxysilane, and 1,3,5-tris(trimethoxysilylpropyl)isocyanate; wherein, γ-(methacryloyloxy)propyltrimethoxysilane achieves significant effects in terms of chemical bonding ability with the polymer matrix, modification effect on inorganic fillers, and weather resistance of the final material. The organic-terminated methacryloyloxy group contains a carbon-carbon double bond (C=C). During the crosslinking process initiated by peroxides (such as BIPB), this double bond can directly participate in the polymer's crosslinking network, forming a strong covalent bond that firmly anchors TTPE-Tr and prevents migration. The inorganic end condenses with rare-earth nanocrystals, improving dispersion and preventing aggregation. The dense network restricts intramolecular rotation, enhancing the AIE aggregation luminescence effect. The trimethoxysilyl group at the inorganic end hydrolyzes to generate silanol, which can undergo condensation reactions with high-refractive-index particles (such as zinc sulfide), UVB absorber carriers, or hydroxyl groups on the glass surface, forming extremely strong Si-O-Me bonds. This effectively prevents particle aggregation and sedimentation, ensuring the transparency and uniformity of the light transfer layer and scattering layer. The resulting interface layer effectively blocks water vapor penetration, protecting the solar cell from corrosion.

[0054] Optionally, in one embodiment, the light stabilizer is selected from bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, bis(2,2,6,6-tetramethylpiperidinyl) sebacate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, (1-octoxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate / mono(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate At least one of bis(2,2,6,6-tetramethylbutyl) sebacate and poly-{[6-[(1,1,3,3,-tetramethylbutyl)-amino]1,3,5,-triazine-2,4-diyl][(2,2,6,6-tetramethylpiperidinyl)-imino]; wherein, bis(2,2,6,6-tetramethylpiperidinyl) sebacate can capture free radicals, quench singlet oxygen, block photo-oxidation chain reaction, protect the conjugated star-shaped skeleton of TTPE-Tr from ultraviolet light degradation, and maintain its aggregation-induced emission activity and long-term photoconversion stability.

[0055] Optionally, in one embodiment, the antioxidant is selected from at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 3,5-di-tert-butyl-4-hydroxybenzyl diethylphosphonate, and 4,4'-p-isopropyl diphenyl C12-15-ol phosphite; wherein, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] terminates the oxidation chain reaction by capturing free radicals, preventing the TTPE-Tr conjugated backbone from being oxidized and destroyed during high-temperature processing and UV aging; its high molecular weight structure is resistant to extraction and has long-lasting stability, ensuring the long-lasting aggregation-induced emission properties and conversion efficiency of TTPE-Tr.

[0056] This invention also proposes a method for preparing a photovoltaic light-converting film with multifunctional up-down conversion, comprising the following steps: (1) Preparation of the cutoff layer: After the UVB absorber, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly, the cutoff layer is prepared by casting film process; the temperature of casting film process is 88~93℃ and the thickness is 0.1~0.2mm; In this embodiment, compared to traditional extrusion blown film or high-temperature casting (typically >140°C), 88~93°C is a low processing temperature, which greatly reduces the volatilization or thermal decomposition loss of UVB absorbers and hindered amine light stabilizers (HALS) under high-temperature shear. The low-temperature process avoids the initial yellowing of the resin matrix due to overheating, ensuring that the initial color of the stop layer is water-white and transparent, without affecting the appearance of the photovoltaic module.

[0057] (2) Preparation of light conversion layer: The upper light conversion agent, the lower light conversion agent and blank particles are mixed, melted, extruded and granulated to obtain light conversion masterbatch. The granulation temperature is 85~100℃. The light conversion masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly and then the light conversion layer is obtained by casting film process. The casting film process temperature is 88~93℃ and the thickness is 0.1~0.2mm. The mixing speed for even mixing in the preparation of light conversion layer is 400~850rpm. In this embodiment, the casting temperature is 88-93°C, ensuring that the active particles in the light conversion masterbatch do not undergo thermal degradation, maintaining the integrity of their crystal or molecular structure, thereby guaranteeing the highest fluorescence quantum yield. The casting temperature of 88-93°C is much lower than the thermal degradation temperature of the resin (EVA / POE), avoiding initial yellowing of the matrix during film formation and ensuring extremely high initial transmittance of the light conversion layer. A rotation speed of 400 rpm or higher provides sufficient shear force to break up the agglomerates of the light conversion masterbatch, allowing the coupling agent to be more uniformly coated on the particle surface, achieving the best molecular bridging effect. Compared to ultra-high-speed dispersion (>1000 rpm), the upper limit of 850 rpm avoids excessive mechanical shear heat. This is particularly important for light stabilizers and antioxidants containing long-chain molecules, preventing polymer chain breakage due to excessive shearing and also reducing bubble formation.

[0058] (3) Preparation of scattering layer: High refractive index particles are mixed with blank particles, and after melting, extrusion and granulation, a refractive masterbatch is obtained. The granulation temperature is 85~100℃. The refractive masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly and then the scattering layer is obtained by casting film process. The casting film process temperature is 88~93℃ and the thickness is 0.1~0.2mm.

[0059] In this embodiment, the granulation temperature is strictly controlled at 85~100℃, which is a relatively mild range. This ensures that the surface modifier (coupling agent) of the high refractive index particles does not undergo thermal decomposition and maintains its oleophilic properties, thereby achieving uniform nanoscale dispersion in the matrix.

[0060] Optionally, in one embodiment, the mixing speed during the preparation of the light conversion layer is 700-850 rpm, which generates sufficient centrifugal and shear forces to effectively break up micron- or even nano-sized powder agglomerates. Only by completely breaking up the agglomerates can the light conversion agent be uniformly distributed in the resin matrix, further avoiding the fluorescence quenching effect caused by excessively high local concentrations (i.e., particles that are too close together do not emit light), ensuring maximum light conversion efficiency and uniform light distribution.

[0061] The present invention will be further described in detail below with reference to specific embodiments.

[0062] Example 1 A photovoltaic light-converting adhesive film with multiple functions, such as... Figure 1 As shown, the light-converting film includes a cutoff layer, a light conversion layer, and a scattering layer: The aforementioned light conversion layer comprises the following components: 100 parts of base resin, 0.2 parts of phototransfer masterbatch, 0.5 parts of crosslinking agent, 0.6 parts of co-crosslinking agent, 0.4 parts of coupling agent, 0.2 parts of light stabilizer, and 0.1 parts of antioxidant.

[0063] The aforementioned cutoff layer comprises the following components: 100 parts of matrix resin, 0.3 parts of UVB absorber, 0.5 parts of crosslinking agent, 0.4 parts of co-crosslinking agent, 0.3 parts of coupling agent, 0.2 parts of light stabilizer, and 0.1 parts of antioxidant.

[0064] The aforementioned scattering layer comprises the following components: 100 parts of matrix resin, 0.3 parts of refractive masterbatch, 0.8 parts of crosslinking agent, 0.5 parts of co-crosslinking agent, 0.3 parts of coupling agent, 0.2 parts of light stabilizer, and 0.1 parts of antioxidant.

[0065] The crosslinking agent mentioned above is selected from 1,1-di-tert-butylperoxide-3,3,5-trimethylcyclohexane; The aforementioned crosslinking agent is selected from triallyl isocyanurate; The coupling agent mentioned above is selected from γ-(methacryloyloxy)propyltrimethoxysilane; The above light stabilizer is selected from bis(2,2,6,6-tetramethylpiperidinyl) sebacate; The antioxidant mentioned above is selected from pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid].

[0066] A method for preparing a photovoltaic light-converting adhesive film with multi-functional up-down switching capability includes the following steps: (1) Preparation of the cutoff layer: After the UVB absorber, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly, the cutoff layer is prepared by casting film process; the temperature of casting film process is 88℃ and the thickness is 0.15mm. (2) Preparation of light conversion layer: The upper light conversion agent, the lower light conversion agent and blank particles are mixed, melted, extruded and granulated to obtain light conversion masterbatch. The granulation temperature is 90℃. The light conversion masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly and then the light conversion layer is obtained by casting film process. The casting film process temperature is 88℃ and the thickness is 0.15mm. The mixing speed for even mixing in the preparation of light conversion layer is 800rpm. (3) Preparation of scattering layer: High refractive index particles are mixed with blank particles, and after melting, extrusion and granulation, a refractive masterbatch is obtained. The granulation temperature is 95℃. After the refractive masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly, the scattering layer is obtained by casting film process. The casting film process temperature is 88℃ and the thickness is 0.1mm.

[0067] The mass ratio of the upper and lower light-converting agents is 2:1; Inorganic rare earth nanomaterials are selected from Yb 3+ -Er 3+ :NaYF4 or Er3+ The organic aggregation-induced emission type triazine star-shaped molecule is TTPE-Tr, with a particle size of 30 nm.

[0068] The UVB absorber is selected from diethylhexylbutamidotriazine ketone; the refractive masterbatch is prepared by mixing high refractive index particles with blank particles, and the high refractive index particles are selected from zinc sulfide.

[0069] Example 2 The difference between Example 2 and Example 1 is that in step (2), the mass ratio of the upper light-converting agent to the lower light-converting agent in the light-converting layer is 1:2, and the mixing speed for uniform mixing in the preparation of the light conversion layer is 400 rpm.

[0070] Example 3 The difference between Example 3 and Example 1 is that in step (2), the mass ratio of the upper light-converting agent to the lower light-converting agent in the light-converting layer is 1:3, and the mixing speed for uniform mixing in the preparation of the light conversion layer is 400 rpm.

[0071] Example 4 The difference between Example 4 and Example 1 is that in step (2), the particle size of the triazine star-shaped molecule of the lower light-converting agent organic aggregation-induced emission type is 50 nm.

[0072] Example 5 The difference between Example 5 and Example 1 is that in step (2), the content of the upconversion agent in the optical conversion masterbatch is 5%; the content of the downconversion agent in the optical conversion masterbatch is 5%.

[0073] Example 6 The difference between Example 6 and Example 1 is that in step (2), the upconversion agent inorganic rare earth nanomaterial is replaced with Er 3+ -Yb 3+ :Gd2O 3。

[0074] Example 7 The difference between Example 7 and Example 1 is that, in step (1), the high refractive index particles in the refractive masterbatch are selected from titanium dioxide.

[0075] Example 8 The difference between Example 8 and Example 1 is that in step (1), the UVB absorber is replaced with ethylhexyltriazine ketone.

[0076] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the light-converting film only includes a cut-off layer and a light conversion layer, and no scattering layer is provided.

[0077] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the cut-off layer in the light-converting film is replaced with a conventional UV cut-off layer, product model F806P / F806PS.

[0078] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the light-converting film only includes a light conversion layer and a scattering layer, and no stop layer is provided.

[0079] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that the light-converting film only includes a cut-off layer and a scattering layer, and no light conversion layer is provided.

[0080] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that the stop layer in the light conversion film is replaced with a conventional UV stop layer, product model F806P / F806PS, and the light conversion layer only includes the lower light conversion agent and blank particles mixed together to obtain the light conversion masterbatch, without the upper light conversion agent added to the light conversion layer.

[0081] Performance testing methods: 1. Spectral transmittance test Test method: The prepared thin film sample is placed in the sample chamber of the spectrophotometer. The wavelength scanning range is set, and the instrument emits light of different wavelengths that pass through the sample; the detector receives the transmitted light intensity. By comparing the incident light intensity and the transmitted light intensity, the transmittance at each wavelength point is calculated. Finally, the data in the 280-380nm and 380-1100nm bands are integrated or weighted averaged to obtain the values ​​in the table.

[0082] 2. Photoluminescence quantum yield test The light-converting film was sandwiched between two pieces of glass for testing to simulate a real-world packaging environment. The sample was excited using light of a specific wavelength. An integrating sphere collected all emitted fluorescence (emission light) and unabsorbed excitation light from the sample. The calculation was: PLQY = number of emitted photons / number of absorbed photons.

[0083] 3. Photovoltaic module power testing Standard test conditions: irradiance 1000 W / m², spectrum AM 1.5G, and cell temperature 25℃.

[0084] Test method: A complete photovoltaic module with a light conversion film attached is placed under a solar simulator. The simulator emits simulated sunlight to illuminate the module. An IV tester scans the module's current-voltage curve. The maximum power point is extracted from the curve.

[0085] 4. UV aging / weathering resistance test and degradation rate Test method (aging): The module is placed in an aging chamber and irradiated for an extended period using ultraviolet lamps (typically simulating the 300-400nm wavelength band). After aging, the module's power is measured again using a solar simulator. Power degradation rate = (initial power - power after aging) / initial power × 100%.

[0086] Table 1 Performance Test Results

[0087] Compared with Comparative Examples 1, 2, 3, 4 and 5, the light-converting films prepared in Examples 1 to 10 have higher visible light transmittance, higher initial power of the components, and are all more than 0.5% higher than conventional UV cut-off / light-converting films (Comparative Example 5). They also have good light stability, and the power is still more than 85% of the initial power after damp heat UV aging.

[0088] Comparing Examples 1 to 10, Example 1 shows that the inorganic light-converting agent is more than the organic light-converting agent, with a ratio of 2:1, and the performance and stability of the light-converting film after aging are relatively optimal when the high rotation speed is 800 rpm.

[0089] The above results indicate that: The key to improving the solar energy utilization efficiency of photovoltaic modules lies in the addition of light conversion agents to the encapsulant film. Specifically, the upper light conversion agent converts infrared light into visible light usable by the photovoltaic module, while the lower light conversion agent converts ultraviolet light into visible light. Adding both upper and lower light conversion agents to the encapsulant film enhances the module's initial power output, i.e., its solar energy utilization efficiency.

[0090] In Example 1, the film utilizes a light-converting agent to convert ultraviolet and infrared light into visible light, which has a high utilization rate in photovoltaic modules, resulting in a 0.6% increase in the initial power of the module compared to Comparative Example 5.

[0091] Furthermore, it exhibits slow UV aging and excellent photostability. This demonstrates that by optimizing the ratio of inorganic upper-conversion agent to organic lower-conversion agent added to the masterbatch and optimizing the mixing speed, the dispersibility and stability of the conversion agent in the film matrix are significantly improved. This results in stable light conversion performance and reduces the adverse effects of UV and near-infrared light on the module, extending its lifespan. Compared to Comparative Example 5, Example 1 shows higher visible light transmittance and higher conversion efficiency, increasing module power by more than 0.2%. Moreover, its preparation process is simple, making it highly valuable for large-scale application in the photovoltaic industry.

[0092] Comparing Examples 1 and 2, it can be seen that, in principle, the higher the content of the inorganic light-converting agent, the lower the transmittance in the visible light region due to material properties. However, the inorganic light-converting agent exhibits better damp heat aging stability than the organic light-converting agent.

[0093] As can be seen from the comparison between Example 1 and Example 3, the inorganic rare earth nanomaterial has a smaller mass than the organic light conversion agent, resulting in poorer performance and stability of the light conversion layer.

[0094] As can be seen from the comparison between Example 1 and Example 4, the particle size of the organic light-converting agent becomes larger, the performance of the light conversion layer deteriorates, and the overall photoelectric conversion efficiency is affected.

[0095] Comparing Example 1 and Example 5, it can be seen that when the inorganic rare earth nanomaterials have the same mass as the organic light-converting agent, the performance of the light conversion layer deteriorates, affecting the overall photoelectric conversion efficiency.

[0096] As can be seen from the comparison between Example 1 and Example 6, if other types of inorganic rare earth nanomaterials are selected as the upconversion agent, the performance of the light conversion layer will be worse, which will affect the overall photoelectric conversion efficiency.

[0097] As can be seen from the comparison between Example 1 and Example 7, the refractive masterbatch is prepared by mixing high refractive index particles with blank particles. If other types of high refractive index particles are selected, the performance of the scattering layer will deteriorate, affecting the overall photoelectric conversion efficiency.

[0098] As can be seen from the comparison between Example 1 and Example 8, when other types of UVB absorbers are selected, the performance of the cut-off layer deteriorates, affecting the overall photoelectric conversion efficiency.

[0099] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A photovoltaic light-converting adhesive film with multi-functional up-down switching capability, characterized in that, It includes a cutoff layer, a light conversion layer, and a scattering layer, wherein the thickness ratio of the cutoff layer, the light conversion layer, and the scattering layer is 1:(0.2~1):(0.2~0.5). The cutoff layer includes a UVB absorber, the light conversion layer includes a light conversion masterbatch, and the scattering layer includes a refractive masterbatch. The light conversion masterbatch is obtained by granulation of a light conversion agent and blank particles, wherein the blank particles are EVA particles or POE particles. The light-converting agent includes an upper light-converting agent and a lower light-converting agent. The upper light-converting agent is an inorganic rare earth nanomaterial, and the lower light-converting agent is an organic aggregation-induced emission type triazine star molecule with a particle size of 30-50 nm. The upconversion agent is present in the masterbatch at a content of 0.1%-10%; The downconversion agent is present in the masterbatch at a content of 0.1%-10%.

2. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The mass ratio of the upper light-converting agent to the lower light-converting agent is (1~2):(1~3).

3. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The mass ratio of the upper light-converting agent to the lower light-converting agent is (1~2):

1.

4. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The inorganic rare earth nanomaterials are selected from Er 3+ Y2O3, Er 3+ ZrO2, Yb 3+ -Er 3+ ZrO2, Er 3+ YAlO3, Er 3+ -Yb 3+ Gd2O3, Er 3+ YF3, Yb 3+ -Er 3+ :NaYF4 or Er 3+ At least one of LaF3; The organic aggregation-induced emission type triazine star molecule is TTPE-Tr.

5. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The UVB absorber is selected from at least one of diethylhexylbutamidotriazinone, 4-methylbenzyl camphor, humosasulfate, ethylhexyl salicylate, ethylhexyl methoxycinnamate, dimethyl PABA ethylhexyl ester, ethylhexyl triazinone, and phenylbenzimidazole sulfonic acid.

6. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The refractive masterbatch is prepared by mixing high refractive index particles with blank particles; the high refractive index particles are selected from at least one of cadmium sulfide, zinc sulfide, cadmium selenide, cadmium telluride, titanium dioxide, and zirconium dioxide.

7. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The light conversion layer comprises the following components: 100 parts of base resin, 0.01-0.5 parts of phototransfer masterbatch, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant.

8. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The cutoff layer comprises the following components: 100 parts of matrix resin, 0.05-0.5 parts of UVB absorber, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant.

9. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to claim 1, characterized in that, The scattering layer comprises the following components: 100 parts of matrix resin, 0.01-0.5 parts of refractive masterbatch, 0.3-1 parts of crosslinking agent, 0.2-0.8 parts of co-crosslinking agent, 0.1-0.6 parts of coupling agent, 0.05-0.3 parts of light stabilizer, and 0.01-0.2 parts of antioxidant.

10. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to any one of claims 5 to 7, characterized in that, The crosslinking agent is selected from at least one of 2-ethylhexyl peroxide tert-amyl carbonate, tert-butyl peroxide 2-ethylhexyl carbonate, 1,1-bis-tert-butyl peroxide-3,3,5-trimethylcyclohexane, tert-butyl peroxide-3,5,5-trimethylhexanoate, and benzoyl peroxide. The crosslinking agent is selected from at least one of the following: trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, triallyl isocyanurate, tetramethyltetravinylcyclotetrasiloxane, 4-acryloylmorpholine, 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate, neopentyl glycol (2)PO diacrylate, polyethylene glycol 200 diacrylate, EO (3) trimethylolpropane triacrylate, and 3(propoxy)glycerol triacrylate. The coupling agent is selected from at least one of the following: vinyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, aminopropyltrimethoxysilane, bis(3-triethoxysilylpropyl)amine, N,N-dimethyl-3-aminopropyltrimethoxysilane, 1,3,5-tris(trimethoxysilylpropyl)isocyanate, n-dodecyltrimethoxysilane, n-octyltrimethoxysilane, cyclohexyltrimethoxysilane, and 1,3,5-tris(trimethoxysilylpropyl)isocyanate.

11. The photovoltaic light-converting adhesive film with up-down multi-functional conversion according to any one of claims 7 to 9, characterized in that, The light stabilizer is selected from at least one of bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, bis(2,2,6,6-tetramethylpiperidinyl) sebacate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, (1-octoxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate / mono(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, and poly-{[6-[(1,1,3,3,-tetramethylbutyl)-amino]1,3,5,-triazine-2,4-diyl][(2,2,6,6-tetramethylpiperidinyl)-imino]; The antioxidant is selected from at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 3,5-di-tert-butyl-4-hydroxybenzyl diethylphosphonate, and 4,4'-p-isopropyl diphenyl C12-15-ol phosphite.

12. The method for preparing the photovoltaic light-converting film with up-down multifunctional conversion according to any one of claims 1 to 11, characterized in that, Includes the following steps: (1) Preparation of the cutoff layer: After the UVB absorber, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly, the cutoff layer is prepared by casting film process; the temperature of casting film process is 88~93℃ and the thickness is 0.1~0.2mm; (2) Preparation of light conversion layer: The upper light conversion agent, the lower light conversion agent and blank particles are mixed, melted, extruded and granulated to obtain light conversion masterbatch. The granulation temperature is 85~100℃. The light conversion masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly and then the light conversion layer is obtained by casting film process. The casting film process temperature is 88~93℃ and the thickness is 0.1~0.2mm. The mixing speed for even mixing in the preparation of light conversion layer is 400~850rpm. (3) Preparation of scattering layer: High refractive index particles are mixed with blank particles, and after melting, extrusion and granulation, a refractive masterbatch is obtained. The granulation temperature is 85~100℃. The refractive masterbatch, crosslinking agent, co-crosslinking agent, coupling agent, light stabilizer and antioxidant are mixed evenly and then the scattering layer is obtained by casting film process. The casting film process temperature is 88~93℃ and the thickness is 0.1~0.2mm.

13. The method for preparing the photovoltaic light-converting adhesive film with up-down multifunctional conversion according to claim 12, characterized in that, In step (2), the mixing speed for uniform mixing during the preparation of the light conversion layer is 700~850 rpm.

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