Ultraviolet conversion adhesive film based on quantum dots as well as preparation method and application of ultraviolet conversion adhesive film

Abstract

The invention relates to the technical field of solar cells, and discloses an ultraviolet conversion adhesive film based on quantum dots and a preparation method and application thereof.The ultraviolet conversion adhesive film comprises the quantum dots, a polymer matrix, an antioxidant, a light stabilizer and a functional additive by mass, the ratio of the quantum dots to the polymer matrix to the antioxidant to the light stabilizer to the functional additive is 1 part: (0.05-2 parts): (1-5 parts): (1-8 parts): (1-10 parts). The ultraviolet conversion adhesive film disclosed by the invention can absorb ultraviolet light and convert the ultraviolet light, so that the damage of the ultraviolet light to a solar cell is reduced; the adhesive film can also be used as a solar cell packaging film, provides excellent protection performance, and improves the photoelectric conversion efficiency and stability of a solar cell.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a quantum dot-based ultraviolet conversion adhesive film and a preparation method and application thereof. Background Art

[0002] As an important representative of new energy, the conversion efficiency and stability of solar cells have always been the focus of research. The spectrum of sunlight ranges from 300nm to 2400nm, which can generally be divided into ultraviolet light, visible light and infrared light. When sunlight is incident on the solar cell module, due to the limitation of the wavelength response of the solar cell material itself, the solar cell can only absorb a part of the light of a specific wavelength. Ultraviolet (UV) is a general term for radiation with a frequency of 750THz-30PHz in the electromagnetic spectrum and a wavelength of 400nm-10nm in a vacuum, which cannot cause people's vision. However, the ultraviolet part of sunlight has a certain negative impact on the performance of solar cells, such as causing aging of packaging materials and reducing battery life. Although the ultraviolet part of the solar spectrum accounts for a small proportion, but the energy is high (accounting for 1~7% of the solar radiation), but the absorption and conversion efficiency of solar cells for ultraviolet light in the existing technology is low.

[0003] Some researchers want to absorb ultraviolet light through perovskite, but they found that traditional perovskite solar cells have a weak ability to absorb ultraviolet light and cannot fully utilize this energy, resulting in a certain amount of energy loss in the photoelectric conversion process. In addition, ultraviolet light can also cause the film of solar cells to turn yellow, causing the photovoltaic components to age and reducing the transmittance of sunlight, thereby further reducing the power generation efficiency of solar cells. Therefore, it is of great significance to develop a solar cell encapsulation film that can efficiently convert ultraviolet light while providing good encapsulation protection. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a quantum dot-based UV conversion adhesive film and a preparation method and application thereof. The UV conversion adhesive film of the present invention can absorb ultraviolet light and convert ultraviolet light, thereby reducing the damage of ultraviolet light to solar cells; the adhesive film can also be used as a solar cell encapsulation film, providing excellent protection performance and improving the photoelectric conversion efficiency and stability of solar cells.

[0005] The present invention provides a quantum dot-based ultraviolet conversion adhesive film, which comprises quantum dots, a polymer matrix, an antioxidant, a light stabilizer and a functional additive. The ratio of the quantum dots, the polymer matrix, the antioxidant, the light stabilizer and the functional additive is 1 part: (0.05 parts to 2 parts): (1 part to 5 parts): (1 part to 8 parts): (1 part to 10 parts) by mass.

[0006] Furthermore, the quantum dots include one or more of cadmium-based quantum dots, sulfur-based quantum dots, perovskite quantum dots, carbon-based quantum dots, metal phosphide quantum dots, metal oxide quantum dots, metal nitride quantum dots, silicon-based quantum dots, and organic quantum dots.

[0007] Furthermore, the general formula of the cadmium-based quantum dots is CdW, wherein W is selected from S 2- 、Se 2- 、Te 2- One or more of .

[0008] Furthermore, the general formula of the sulfur-based quantum dots is M1 x S y , where M1 is selected as Zn 2+ 、Cd 2+ 、Ag + One or more of, x and y are determined by the method of balancing the chemical formula of sulfur-based quantum dots.

[0009] Furthermore, the general formula of the perovskite quantum dot is ABR3, wherein A is selected from one or more of formamidinium ion, methylamine ion, and cesium ion; B is selected from Pb 2+ Sn 2+ 、Eu 2+ , Cu 2+ 、Ni 2+ One or more of; R is selected from one or more of halogen ions.

[0010] Furthermore, the carbon-based quantum dots include carbon-based quantum dots composed of one or more elements selected from C, O, N and H.

[0011] Furthermore, the general formula of the metal phosphide quantum dot is M2 x1 P y1 , wherein M2 is selected from In 3+ , Ga 3+ 、Zn 2+ , Cu 2+ One or more of, x1 and y1 are determined by the method of balancing the chemical formula of metal phosphide quantum dots.

[0012] Furthermore, the general formula of the metal oxide quantum dot is M3 x2 O y2 , wherein M3 is selected from Cu 2+ 、Zn 2+ , Fe 3+ , Ba 2+ 、Ti + , Li + , Mn 3+ , Mn 4+One or more of, x2 and y2 are determined by the chemical formula balancing method of metal oxide quantum dots.

[0013] Furthermore, the general formula of the metal nitride quantum dot is M4 x3 N y3 , wherein M4 is selected from Ti 3+ 、Al 3+ , Ga 3+ , Fe 3+ , Fe 4+ One or more of, x3 and y3 are determined by the method of chemical formula balancing of metal nitride quantum dots.

[0014] Furthermore, the silicon-based quantum dots include one or more of intrinsic silicon-based quantum dots and doped silicon-based quantum dots.

[0015] Furthermore, the organic quantum dots include one or more of conjugated polymer quantum dots, dendrimer quantum dots, and organic small molecular weight quantum dots.

[0016] Furthermore, the size of the quantum dots is 3nm~30nm.

[0017] Furthermore, the main absorption band of the quantum dots is lower than 1000nm, and the emission wavelength is between 300nm and 1000nm.

[0018] Furthermore, the polymer matrix includes one or more of polyvinyl alcohol (PVA), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene-polyvinyl acetate copolymer (EVA), ethylene and octene copolymer (POE), polyvinyl butyral (PVB), polyvinylidene fluoride (PVDF), polyvinyl acetate (PVAc), cellulose acetate (CA), polysulfone (PSU), aromatic polyamide (PPA), polyimide (PI), polystyrene (PS), polymethyl methacrylate (PMMA), thermoplastic polyolefin (TPO), and polyurethane (PU).

[0019] Furthermore, the antioxidant includes one or more of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 1076 (β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 168 (tris[2.4-di-tert-butylphenyl] phosphite), ethylenediaminetetraacetic acid (EDTA), diphenylamine, and p-phenylenediamine.

[0020] Furthermore, the light stabilizer includes one or more of titanium dioxide (TiO2), zinc oxide (ZnO), nickel-dithiocarbamate complex, 2-(2'-hydroxy-5'-tert-octylphenyl) benzotriazole; triphenyl phosphite, light stabilizer 622, BASF Tinuvin 770, BASF Tinuvin 622, and Chimassorb 944.

[0021] Furthermore, the functional additives include one or more of organic small molecule passivators, high molecular polymer passivators, surfactants, high molecular dispersants, amino acids and their derivatives, organic phosphonic acid compounds, conductive polymer additives, and small molecule hole transport material additives.

[0022] Furthermore, the organic small molecule passivator includes one or more of ethylenediaminetetraacetic acid (EDTA), triethanolamine (TEA), acetylacetone (acac), pyridine (Py) and aniline (An).

[0023] Furthermore, the high molecular polymer passivator includes one or more of polyvinyl pyrrolidone (PVP), polystyrene (PS), polyethylene glycol (PEG) and polyacrylic acid (PAA).

[0024] Furthermore, the surfactant includes one or more of sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), polyoxyethylene sorbitan monooleate (Tween-80), Triton X-100 (Triton X-100) and aureeth-7 (AEO-7).

[0025] Further, the polymer dispersant includes one or more of polycarboxylic acid sodium salt (PAA-Na), polystyrene-maleic anhydride copolymer (SMA), sodium polyacrylate (PAAS), polyvinyl butyral (PVB) and polyamide-amine (PAMAM) dendritic macromolecules. Furthermore, the amino acids and their derivatives include one or more of glycine (Gly), lysine (Lys), cysteine ​​(Cys), glutamic acid (Glu) and phenylalanine (Phe).

[0026] Furthermore, the organic phosphonic acid compound includes one or more of aminotrimethylenephosphonic acid (ATMP), ethylenediaminetetramethylenephosphonic acid (EDTMP), 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), hydroxyethylidene diphosphonic acid (HEDP) and hexamethylenediaminetetramethylenephosphonic acid (HDTMP).

[0027] Furthermore, the conductive polymer additive includes one or more of polyaniline (PANI), polythiophene (PTh), polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(p-phenylenevinylene) (PPV).

[0028] Further, the small molecule hole transport material additive includes one or more of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), N,N'-di(1-naphthyl)-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (α-NPD), spiro-bifluorene-9,9'-bis(9-phenyl-9H-carbazole) (Spiro-OMeTAD), 4-(diphenylamino)benzaldehyde (DPAB) and tris(4-bromophenyl)amine (TBPA).

[0029] The present invention also provides a method for preparing the ultraviolet conversion adhesive film, which comprises mixing quantum dots, a polymer matrix, a light stabilizer, an antioxidant and a functional additive to form a film.

[0030] Furthermore, the film forming temperature is 140°C-200°C.

[0031] Furthermore, the quantum dots include one or more of cadmium-based quantum dots, sulfur-based quantum dots, perovskite quantum dots, carbon-based quantum dots, metal phosphide quantum dots, metal oxide quantum dots, metal nitride quantum dots, silicon-based quantum dots, and organic quantum dots.

[0032] Furthermore, the general formula of the cadmium-based quantum dots is CdW, wherein W is selected from S 2- 、Se 2- 、Te 2- One or more of .

[0033] Furthermore, the general formula of the sulfur-based quantum dots is M1 x S y , where M1 is selected as Zn 2+ 、Cd 2+ 、Ag + One or more of, x and y are determined by the method of balancing the chemical formula of sulfur-based quantum dots.

[0034] Furthermore, the general formula of the perovskite quantum dot is ABR3, wherein A is selected from one or more of formamidinium ion, methylamine ion, and cesium ion; B is selected from Pb 2+ Sn 2+ 、Eu 2+ , Cu 2+ 、Ni 2+ One or more of; R is selected from one or more of halogen ions.

[0035] Furthermore, the carbon-based quantum dots include carbon-based quantum dots composed of one or more elements selected from C, O, N and H.

[0036] Furthermore, the general formula of the metal phosphide quantum dot is M2 x1 P y1 , wherein M2 is selected from In 3+ , Ga 3+ 、Zn 2+ , Cu 2+ One or more of, x1 and y1 are determined by the method of balancing the chemical formula of metal phosphide quantum dots.

[0037] Furthermore, the general formula of the metal oxide quantum dot is M3 x2 O y2 , wherein M3 is selected from Cu 2+ 、Zn 2+ , Fe 3+ , Ba 2+ 、Ti + , Li + , Mn 3+ , Mn 4+ One or more of, x2 and y2 are determined by the chemical formula balancing method of metal oxide quantum dots.

[0038] Furthermore, the general formula of the metal nitride quantum dot is M4 x3 N y3 , wherein M4 is selected from Ti 3+ 、Al 3+ , Ga 3+ , Fe 3+ , Fe 4+ One or more of, x3 and y3 are determined by the method of chemical formula balancing of metal nitride quantum dots.

[0039] Furthermore, the silicon-based quantum dots include one or more of intrinsic silicon-based quantum dots and doped silicon-based quantum dots.

[0040] Furthermore, the organic quantum dots include one or more of conjugated polymer quantum dots, dendrimer quantum dots, and organic small molecular weight quantum dots.

[0041] Furthermore, the size of the quantum dots is 3nm~30nm.

[0042] Furthermore, the polymer matrix includes one or more of polyvinyl alcohol (PVA), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene-polyvinyl acetate copolymer (EVA), ethylene and octene copolymer (POE), polyvinyl butyral (PVB), polyvinylidene fluoride (PVDF), polyvinyl acetate (PVAc), cellulose acetate (CA), polysulfone (PSU), aromatic polyamide (PPA), polyimide (PI), polystyrene (PS), polymethyl methacrylate (PMMA), thermoplastic polyolefin (TPO), and polyurethane (PU).

[0043] Furthermore, the antioxidant includes one or more of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 1076 (β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 168 (tris[2.4-di-tert-butylphenyl] phosphite), ethylenediaminetetraacetic acid (EDTA), diphenylamine, p-phenylenediamine, etc.

[0044] Furthermore, the light stabilizer includes one or more of titanium dioxide (TiO2), zinc oxide (ZnO), nickel-dithiocarbamate complex, 2-(2'-hydroxy-5'-tert-octylphenyl) benzotriazole; triphenyl phosphite, light stabilizer 622, BASF Tinuvin 770, BASF Tinuvin 622, and Chimassorb 944.

[0045] Furthermore, the functional additives include one or more of organic small molecule passivators, high molecular polymer passivators, surfactants, high molecular dispersants, amino acids and their derivatives, organic phosphonic acid compounds, conductive polymer additives, and small molecule hole transport material additives.

[0046] Furthermore, the organic small molecule passivator includes one or more of ethylenediaminetetraacetic acid (EDTA), triethanolamine (TEA), acetylacetone (acac), pyridine (Py) and aniline (An).

[0047] Furthermore, the high molecular polymer passivator includes one or more of polyvinyl pyrrolidone (PVP), polystyrene (PS), polyethylene glycol (PEG) and polyacrylic acid (PAA).

[0048] Furthermore, the surfactant includes one or more of sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), polyoxyethylene sorbitan monooleate (Tween-80), Triton X-100 (Triton X-100) and aureeth-7 (AEO-7).

[0049] Furthermore, the polymer dispersant includes one or more of polycarboxylic acid sodium salt (PAA-Na), polystyrene-maleic anhydride copolymer (SMA), sodium polyacrylate (PAAS), polyvinyl butyral (PVB) and polyamide-amine (PAMAM) dendritic macromolecules.

[0050] Furthermore, the amino acids and their derivatives include one or more of glycine (Gly), lysine (Lys), cysteine ​​(Cys), glutamic acid (Glu) and phenylalanine (Phe).

[0051] Furthermore, the organic phosphonic acid compound includes one or more of aminotrimethylenephosphonic acid (ATMP), ethylenediaminetetramethylenephosphonic acid (EDTMP), 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), hydroxyethylidene diphosphonic acid (HEDP) and hexamethylenediaminetetramethylenephosphonic acid (HDTMP).

[0052] Furthermore, the conductive polymer additive includes one or more of polyaniline (PANI), polythiophene (PTh), polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(p-phenylenevinylene) (PPV).

[0053] Further, the small molecule hole transport material additive includes one or more of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), N,N'-di(1-naphthyl)-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (α-NPD), spiro-bifluorene-9,9'-bis(9-phenyl-9H-carbazole) (Spiro-OMeTAD), 4-(diphenylamino)benzaldehyde (DPAB) and tris(4-bromophenyl)amine (TBPA).

[0054] The present invention also provides the use of the ultraviolet conversion adhesive film as a battery packaging film of a solar cell.

[0055] The embodiments of the present invention have the following technical effects: 1. The UV conversion film provided by the present invention combines the excellent UV conversion performance of quantum dots and the good packaging performance of the polymer matrix, providing a new packaging solution for solar cells. By precisely controlling the synthesis and preparation process, the uniform distribution and high stability of quantum dots in the film are achieved, ensuring the efficient conversion of UV light and the improvement of battery performance.

[0056] 2. The UV conversion adhesive film of the present invention has good light transmittance, thermal stability and weather resistance, and can protect solar cells from damage by ultraviolet light and extend the battery life.

[0057] 3. The ultraviolet conversion film of the present invention can absorb ultraviolet light and convert it, thereby reducing the damage of ultraviolet light to solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0059] Figure 1 is a flow chart of a method provided by an embodiment of the present invention; Figure 2 The UV test graph (dashed line) and PL test graph (solid line) of the CdSe UV conversion film provided in Example 1 of the present invention; Figure 3 The UV test graph (dashed line) and PL test graph (solid line) of the ZnS UV conversion film provided in Example 2 of the present invention; Figure 4 It is CsPbBr provided in Example 3 of the present invention. 0.5 Cl 2.5 TEM image of perovskite quantum dots; Figure 5 It is CsPbBr provided in Example 3 of the present invention. 0.5 Cl 2.5 UV test graph (dashed line) and PL test graph (solid line) of UV conversion film; Figure 6 1 is a UV test graph (dashed line) and a PL test graph (solid line) of the CsPbBr3 ultraviolet conversion film provided in Example 4 of the present invention; Figure 7 1 is a UV test graph (dashed line) and a PL test graph (solid line) of the CsPbI3 UV conversion film provided in Example 5 of the present invention; Figure 8 It is a comparison of the membrane permeabilities obtained in Example 1 of the present invention and Comparative Example 1. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0061] In the first aspect, some embodiments of the present invention provide a quantum dot-based UV conversion adhesive film, which includes quantum dots, a polymer matrix, an antioxidant, a light stabilizer and a functional additive. By mass, the ratio of the quantum dots, the polymer matrix, the antioxidant, the light stabilizer and the functional additive is 1 part: (0.05 parts to 2 parts): (1 part to 5 parts): (1 part to 8 parts): (1 part to 10 parts).

[0062] In some embodiments, the quantum dots include one or more of cadmium-based quantum dots, sulfur-based quantum dots, perovskite quantum dots, carbon-based quantum dots, metal phosphide quantum dots, metal oxide quantum dots, metal nitride quantum dots, silicon-based quantum dots, and organic quantum dots.

[0063] In some embodiments, the general formula of the cadmium-based quantum dots is CdW, wherein W is selected from S 2- 、Se 2- 、Te 2- One or more of .

[0064] In some embodiments, the general formula of the sulfur-based quantum dots is M1 x S y , where M1 is selected as Zn 2+ 、Cd 2+ 、Ag + One or more of, x and y are determined by the method of balancing the chemical formula of sulfur-based quantum dots.

[0065] In some embodiments, the general formula of the perovskite quantum dot is ABR3, wherein A is selected from one or more of formamidinium ion, methylamine ion, and cesium ion; B is selected from Pb 2+ Sn 2+ 、Eu 2+ , Cu 2+ 、Ni 2+ One or more of; R is selected from one or more of halogen ions.

[0066] In some embodiments, the carbon-based quantum dots include carbon-based quantum dots composed of one or more elements selected from C, O, N and H.

[0067] In some embodiments, the general formula of the metal phosphide quantum dot is M2x1 P y1 , wherein M2 is selected from In 3+ , Ga 3+ 、Zn 2+ , Cu 2+ One or more of, x1 and y1 are determined by the method of balancing the chemical formula of metal phosphide quantum dots.

[0068] In some embodiments, the general formula of the metal oxide quantum dot is M3 x2 O y2 , wherein M3 is selected from Cu 2+ 、Zn 2+ , Fe 3+ , Ba 2+ 、Ti + , Li + , Mn 3+ , Mn 4+ One or more of, x2 and y2 are determined by the chemical formula balancing method of metal oxide quantum dots.

[0069] In some embodiments, the general formula of the metal nitride quantum dot is M4 x3 N y3 , wherein M4 is selected from Ti 3+ 、Al 3+ , Ga 3+ , Fe 3+ , Fe 4+ One or more of, x3 and y3 are determined by the method of chemical formula balancing of metal nitride quantum dots.

[0070] In some embodiments, the silicon-based quantum dots include one or more of intrinsic silicon-based quantum dots and doped silicon-based quantum dots.

[0071] In some embodiments, the organic quantum dots include one or more of conjugated polymer quantum dots, dendrimer quantum dots, and organic small molecular weight quantum dots.

[0072] In some embodiments, the size of the quantum dots is 3-30 nm.

[0073] Synthesis of quantum dots in the present invention. Using hot injection method, sol-gel method or other suitable methods, under the protection of inert gas, the perovskite precursor solution is mixed with the solvent, and the temperature, time and reaction conditions are precisely controlled to synthesize quantum dots with uniform size and excellent ultraviolet conversion performance. Specifically, the main absorption band of the quantum dots of the present invention is below 1000nm, the emission wavelength is in the range of 300nm to 1000nm, the fluorescence yield of the quantum dots is greater than 70%, and the half-peak width is less than 50nm.

[0074] In some embodiments, the polymer matrix includes one or more of polyvinyl alcohol (PVA), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene-polyvinyl acetate copolymer (EVA), ethylene and octene copolymer (POE), polyvinyl butyral (PVB), polyvinylidene fluoride (PVDF), polyvinyl acetate (PVAc), cellulose acetate (CA), polysulfone (PSU), aromatic polyamide (PPA), polyimide (PI), polystyrene (PS), polymethyl methacrylate (PMMA), thermoplastic polyolefin (TPO), and polyurethane (PU).

[0075] In some embodiments, the antioxidant includes one or more of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 1076 (β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 168 (tris[2.4-di-tert-butylphenyl] phosphite), ethylenediaminetetraacetic acid (EDTA), diphenylamine, p-phenylenediamine, etc.

[0076] In some embodiments, the light stabilizer includes one or more of titanium dioxide (TiO2), zinc oxide (ZnO), nickel-dithiocarbamate complex, 2-(2'-hydroxy-5'-tert-octylphenyl) benzotriazole; triphenyl phosphite, light stabilizer 622, BASF Tinuvin 770, BASF Tinuvin 622, and Chimassorb 944.

[0077] In some embodiments, the functional additives include one or more of organic small molecule passivators, high molecular polymer passivators, surfactants, high molecular dispersants, amino acids and their derivatives, organic phosphonic acid compounds, conductive polymer additives, and small molecule hole transport material additives.

[0078] In some embodiments, the organic small molecule passivator includes one or more of ethylenediaminetetraacetic acid (EDTA), triethanolamine (TEA), acetylacetone (acac), pyridine (Py) and aniline (An).

[0079] In some embodiments, the polymer passivator includes one or more of polyvinyl pyrrolidone (PVP), polystyrene (PS), polyethylene glycol (PEG) and polyacrylic acid (PAA).

[0080] In some embodiments, the surfactant includes one or more of sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), polyoxyethylene sorbitan monooleate (Tween-80), Triton X-100 and laureth-7 (AEO-7).

[0081] In some embodiments, the polymer dispersant includes one or more of polycarboxylic acid sodium salt (PAA-Na), polystyrene-maleic anhydride copolymer (SMA), sodium polyacrylate (PAAS), polyvinyl butyral (PVB) and polyamide-amine (PAMAM) dendrimers. In some embodiments, the amino acids and their derivatives include one or more of glycine (Gly), lysine (Lys), cysteine ​​(Cys), glutamic acid (Glu) and phenylalanine (Phe).

[0082] In some embodiments, the organic phosphonic acid compound includes one or more of aminotrimethylenephosphonic acid (ATMP), ethylenediaminetetramethylenephosphonic acid (EDTMP), 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), hydroxyethylidene diphosphonic acid (HEDP) and hexamethylenediaminetetramethylenephosphonic acid (HDTMP).

[0083] In some embodiments, the conductive polymer additive includes one or more of polyaniline (PANI), polythiophene (PTh), polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT), and poly(p-phenylenevinylene) (PPV).

[0084] In some embodiments, the small molecule hole transport material additive includes one or more of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), N,N'-di(1-naphthyl)-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (α-NPD), spiro-bifluorene-9,9'-bis(9-phenyl-9H-carbazole) (Spiro-OMeTAD), 4-(diphenylamino)benzaldehyde (DPAB) and tris(4-bromophenyl)amine (TBPA).

[0085] In a second aspect, some embodiments of the present invention also provide a method for preparing the UV conversion adhesive film, which comprises mixing quantum dots, a polymer matrix, a light stabilizer, an antioxidant and a functional additive into a film.

[0086] The synthesized quantum dots are mixed with a polymer matrix, a light stabilizer, an antioxidant and functional additives, and a uniformly distributed UV conversion adhesive film is formed through solution casting, hot pressing or other suitable molding processes.

[0087] In some embodiments, the film forming temperature is 140°C-200°C.

[0088] In some embodiments, the quantum dots include one or more of cadmium-based quantum dots, sulfur-based quantum dots, perovskite quantum dots, carbon-based quantum dots, metal phosphide quantum dots, metal oxide quantum dots, metal nitride quantum dots, silicon-based quantum dots, and organic quantum dots.

[0089] In some embodiments, the general formula of the cadmium-based quantum dots is CdW, wherein W is selected from S 2- 、Se 2- 、Te 2- One or more of .

[0090] In some embodiments, the general formula of the sulfur-based quantum dots is M1 x S y , where M1 is selected as Zn 2+ 、Cd 2+ 、Ag + One or more of, x and y are determined by the method of balancing the chemical formula of sulfur-based quantum dots.

[0091] In some embodiments, the general formula of the perovskite quantum dot is ABR3, wherein A is selected from one or more of formamidinium ion, methylamine ion, and cesium ion; B is selected from Pb 2+ Sn 2+ 、Eu 2+ , Cu 2+ 、Ni 2+ One or more of; R is selected from one or more of halogen ions.

[0092] In some embodiments, the carbon-based quantum dots include carbon-based quantum dots composed of one or more elements selected from C, O, N and H.

[0093] In some embodiments, the general formula of the metal phosphide quantum dot is M2 x1 P y1 , wherein M2 is selected from In 3+ , Ga 3+ 、Zn 2+ , Cu 2+ One or more of, x1 and y1 are determined by the method of balancing the chemical formula of metal phosphide quantum dots.

[0094] In some embodiments, the general formula of the metal oxide quantum dot is M3x2 O y2 , wherein M3 is selected from Cu 2+ 、Zn 2+ , Fe 3+ , Ba 2+ 、Ti + , Li + , Mn 3+ , Mn 4+ One or more of, x2 and y2 are determined by the chemical formula balancing method of metal oxide quantum dots.

[0095] In some embodiments, the general formula of the metal nitride quantum dot is M4 x3 N y3 , wherein M4 is selected from Ti 3+ 、Al 3+ , Ga 3+ , Fe 3+ , Fe 4+ One or more of, x3 and y3 are determined by the method of chemical formula balancing of metal nitride quantum dots.

[0096] In some embodiments, the silicon-based quantum dots include one or more of intrinsic silicon-based quantum dots and doped silicon-based quantum dots.

[0097] In some embodiments, the organic quantum dots include one or more of conjugated polymer quantum dots, dendrimer quantum dots, and organic small molecular weight quantum dots.

[0098] In some embodiments, the size of the quantum dots is 3 nm to 30 nm.

[0099] In some embodiments, the polymer matrix includes one or more of polyvinyl alcohol (PVA), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene-polyvinyl acetate copolymer (EVA), ethylene and octene copolymer (POE), polyvinyl butyral (PVB), polyvinylidene fluoride (PVDF), polyvinyl acetate (PVAc), cellulose acetate (CA), polysulfone (PSU), aromatic polyamide (PPA), polyimide (PI), polystyrene (PS), polymethyl methacrylate (PMMA), thermoplastic polyolefin (TPO), and polyurethane (PU).

[0100] In some embodiments, the antioxidant includes one or more of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 1076 (β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), antioxidant 168 (tris[2.4-di-tert-butylphenyl] phosphite), ethylenediaminetetraacetic acid (EDTA), diphenylamine, p-phenylenediamine, etc.

[0101] In some embodiments, the light stabilizer includes one or more of titanium dioxide (TiO2), zinc oxide (ZnO), nickel-dithiocarbamate complex, 2-(2'-hydroxy-5'-tert-octylphenyl) benzotriazole; triphenyl phosphite, light stabilizer 622, BASF Tinuvin 770, BASF Tinuvin 622, and Chimassorb 944.

[0102] In some embodiments, the functional additives include one or more of organic small molecule passivators, high molecular polymer passivators, surfactants, high molecular dispersants, amino acids and their derivatives, organic phosphonic acid compounds, conductive polymer additives, and small molecule hole transport material additives.

[0103] In some embodiments, the organic small molecule passivator includes one or more of ethylenediaminetetraacetic acid (EDTA), triethanolamine (TEA), acetylacetone (acac), pyridine (Py) and aniline (An).

[0104] In some embodiments, the polymer passivator includes one or more of polyvinyl pyrrolidone (PVP), polystyrene (PS), polyethylene glycol (PEG) and polyacrylic acid (PAA).

[0105] In some embodiments, the surfactant includes one or more of sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), polyoxyethylene sorbitan monooleate (Tween-80), Triton X-100 and laureth-7 (AEO-7).

[0106] In some embodiments, the polymer dispersant includes one or more of polycarboxylic acid sodium salt (PAA-Na), polystyrene-maleic anhydride copolymer (SMA), sodium polyacrylate (PAAS), polyvinyl butyral (PVB) and polyamide-amine (PAMAM) dendrimers. In some embodiments, the amino acids and their derivatives include one or more of glycine (Gly), lysine (Lys), cysteine ​​(Cys), glutamic acid (Glu) and phenylalanine (Phe).

[0107] In some embodiments, the organic phosphonic acid compound includes one or more of aminotrimethylenephosphonic acid (ATMP), ethylenediaminetetramethylenephosphonic acid (EDTMP), 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), hydroxyethylidene diphosphonic acid (HEDP) and hexamethylenediaminetetramethylenephosphonic acid (HDTMP).

[0108] In some embodiments, the conductive polymer additive includes one or more of polyaniline (PANI), polythiophene (PTh), polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT), and poly(p-phenylenevinylene) (PPV).

[0109] In some embodiments, the small molecule hole transport material additive includes one or more of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), N,N'-di(1-naphthyl)-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (α-NPD), spiro-bifluorene-9,9'-bis(9-phenyl-9H-carbazole) (Spiro-OMeTAD), 4-(diphenylamino)benzaldehyde (DPAB) and tris(4-bromophenyl)amine (TBPA).

[0110] On the third aspect, some embodiments of the present invention further provide the use of the UV conversion adhesive film as a battery packaging film for solar cells.

[0111] The following is described in conjunction with the embodiments and comparative examples: Embodiment 1:

[0112] Step (1): Mix 2.5 mmol of selenium powder, 1.0 mL of trioctylphosphine sulfide (TOP) and 10.0 mL of 1-octadecene (ODE), evacuate the reaction bottle for 80 min, then increase the temperature and heat to 250 °C under nitrogen protection for 2 h to obtain a selenium precursor for use.

[0113] Step (2): 3 mmol of CdO, 5.5 mL of oleic acid (OA) and 50 mL of ODE were mixed, vacuumed and heated to 180°C. After all the solids were dissolved, the mixture was cooled to room temperature, 3.5 mL of OA and 3.5 mL of oleylamine (OAm) were added, and the temperature was then raised to 240°C. After reaching the temperature, the selenium precursor (3 mL) in step (1) heated to 250°C was immediately injected. After reacting for 30 s, the heating jacket was removed, and the mixture was cooled to room temperature using an ice water bath. The mixture was centrifuged and purified using methyl acetate at a speed of 6500 rpm for 10 min to obtain CdSe quantum dots, which were then stored in n-hexane for later use. In the present invention, CdSe quantum dots can also be obtained commercially.

[0114] Step (3): Take 0.5 mL of the CdSe quantum dots (10 mg / mL) obtained in step (2), 5 mg of the polymer matrix (POE), 7.5 mg of the antioxidant 1010, 15 mg of the light stabilizer (TiO2) and 10 mg of the functional additive (PVP), mix them evenly, put them into a twin-screw extruder for extrusion, and the resulting film is a UV conversion film.

[0115] Among them, the temperature of the screw is set to 140℃-160℃-180℃-180℃-160℃-140℃, the heating rate is 5℃ / min, the cooling rate is 5℃ / min, the screw speed is 20rmp, the traction speed is 10rmp, and the thickness of the obtained UV conversion film is 500μm.

[0116] Step (4): Testing the UV conversion film.

[0117] Embodiment 2:

[0118] Step (1): Mix 2.5 mmol sulfur powder, 1.0 mL TOP and 10.0 mL ODE, evacuate the reaction bottle for 80 min, then increase the temperature and heat to 200 °C under nitrogen protection for 2 h to obtain a sulfur precursor for use.

[0119] Step (2): 3 mmol of zinc acetate (Zn(CH3COO)2) and 5.5 mL of OA and 50 mL of ODE were mixed, vacuumed and heated to 150°C. After the solid was completely dissolved, it was cooled to room temperature, 3.5 mL of OA and 3.5 mL of OAm were added, and the temperature was then raised to 180°C. After reaching the temperature, the selenium precursor (3 mL) in step (1) heated to 200°C was immediately injected. After reacting for 30 s, the heating jacket was removed, and the mixture was cooled to room temperature using an ice water bath. The mixture was centrifuged and purified with methyl acetate at a speed of 6500 rpm for 10 min to obtain ZnS quantum dots, which were then stored in n-hexane for later use. In the present invention, ZnS quantum dots can also be obtained commercially.

[0120] Step (3): Take 0.5 mL of the ZnS quantum dots (10 mg / mL) obtained in step (2), 5 mg of the polymer matrix (POE), 7.5 mg of the antioxidant 1010, 15 mg of the light stabilizer (TiO2) and 10 mg of the functional additive (PVP), mix them evenly, put them into a twin-screw extruder for extrusion, and the resulting film is a UV conversion film.

[0121] Among them, the temperature of the screw is set to 140℃-160℃-180℃-180℃-160℃-140℃, the heating rate is 5℃ / min, the cooling rate is 5℃ / min, the screw speed is 20rmp, the traction speed is 10rmp, and the thickness of the obtained UV conversion film is 500μm.

[0122] Step (4): Testing the UV conversion film.

[0123] Embodiment 3:

[0124] Step (1): After mixing 2.5 mmol of cesium carbonate (Cs2CO3), 2 mL of oleic acid (OA) and 30 mL of 1-octadecene (ODE), the reaction bottle was evacuated for 80 min, and then the temperature was increased and heated to 150°C under nitrogen protection and maintained for 2 h, thereby obtaining a clear cesium oleate solution.

[0125] Step (2): 35 mL of ODE and 2 mmol of lead bromide (PbBr2) and chlorine bromide (PbCl2) were mixed, wherein the molar ratio of lead bromide to chlorine bromide was 0.5:2.5, and the mixture was heated to 150°C under vacuum. Then, 3 mL of OA and 3 mL of oleylamine (OAm) were added under nitrogen protection, and the temperature was raised to 180°C. After reaching the temperature, the cesium oleate heated to 150°C in step (1) was immediately injected, and then the mixture was quickly cooled to room temperature in an ice water bath, and centrifuged with methyl acetate at a speed of 8000 rpm for 5 min to obtain CsPbBr 0.5 Cl 2.5The perovskite quantum dots were then stored in n-hexane for later use.

[0126] Step (3): Take 0.5 mL of CsPbBr obtained in step (2) 0.5 Cl 2.5 Quantum dots (10 mg / mL), 5 mg polymer matrix (POE), 7.5 mg antioxidant 1010, 15 mg light stabilizer (TiO2) and 10 mg functional additive (PVP) are uniformly mixed and put into a twin-screw extruder for extrusion. The resulting film is a UV conversion film.

[0127] Among them, the temperature of the screw is set to 140℃-160℃-180℃-180℃-160℃-140℃, the heating rate is 5℃ / min, the cooling rate is 5℃ / min, the screw speed is 20rmp, the traction speed is 10rmp, and the thickness of the obtained UV conversion film is 500μm.

[0128] Step (4): Testing the UV conversion film.

[0129] Embodiment 4:

[0130] The difference between Example 4 and Example 3 is that only lead bromide is added in step (2), and the prepared perovskite quantum dots are CsPbBr3, and the rest are the same as those in Example 3.

[0131] Embodiment 5:

[0132] The difference between Example 5 and Example 3 is that in step (2), lead iodide is used instead of lead bromide and chlorine bromide, and the prepared perovskite quantum dots are CsPbI3, and the rest are the same as those in Example 3.

[0133] Comparative Example 1: The difference between Comparative Example 1 and Example 3 is that no perovskite quantum dots are added, and the rest is the same as Example 3.

[0134] The embodiments and comparative examples were tested: Transmission Electron Microscope (TEM): This experiment uses JEOL's JEM-2800 TEM to observe microstructures at the micrometer and nanometer scales. Before scanning, the quantum point solution to be measured needs to be dispersed on a micro-grid copper mesh covered with an ultra-thin carbon film and observed after it is fully dried.

[0135] Steady-state Photoluminescence Spectra (PL): When the sample is excited by light, electrons jump from the valence band to the conduction band and leave holes in the valence band. The electrons in the conduction band and the holes in the valence band relax to the bottom of the conduction band or the top of the valence band, and then emit photons through radiation recombination to return to the ground state, thus forming a spectrum of light with different wavelengths and intensities. The steady-state photoluminescence spectrometer used in this experiment is Edinburgh's FS5, with an excitation wavelength of 450nm.

[0136] UV-Vis Absorption Spectrum: Prepare the quantum film on the substrate, ensure the uniformity and integrity of the film, put it into the sample cell of the UV-visible spectrophotometer, set the wavelength range to 200~800nm, and measure the absorbance or transmittance at different wavelengths. According to the formula T=10 -A (Where T is transmittance and A is absorbance) Calculate the transmittance at each wavelength. The UV spectrophotometer used in this experiment is Cary 100 from Varian.

[0137] Results and Analysis: Through the method of the present invention, a UV conversion film is successfully obtained, such as Figure 1 shown.

[0138] like Figure 2 This is a PL test image of the CdSe UV conversion film prepared in Example 1, with an emission position at 547 nm and a FWHM of 36 nm.

[0139] like Figure 3 This is a PL test image of the ZnS UV conversion film prepared in Example 2, with an emission position at 507 nm and a FWHM of 26 nm.

[0140] like Figure 4 The CsPbBr prepared in Example 3 0.5 Cl 2.5 TEM image of quantum dots showing uniform and monodisperse cubic shapes of CsPbBr 0.5 Cl 2.5 The morphology of quantum dots.

[0141] like Figure 5 The CsPbBr prepared in Example 3 0.5 Cl 2.5 PL test chart of UV conversion film, the emission position is 409nm, and the FWHM is 18nm.

[0142] like Figure 6 This is a PL test image of the CsPbBr3 UV conversion film prepared in Example 4, with an emission position at 508 nm and a FWHM of 25 nm.

[0143] like Figure 7 This is a PL test image of the CsPbI3 UV conversion film prepared in Example 5, with an emission position at 682nm and a FWHM of 32nm.

[0144] like Figure 8 The CsPbBr prepared in Example 3 0.5 Cl 2.5 The transmittance diagram of the UV conversion film shows that the transmittance of the visible light part is >91%.

[0145] In summary, the ultraviolet conversion film of the present invention can absorb ultraviolet light and convert it, thereby reducing the damage of ultraviolet light to solar cells.

[0146] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A quantum dot-based ultraviolet conversion film, characterized in that: The UV conversion film includes quantum dots, a polymer matrix, an antioxidant, a light stabilizer and a functional additive. By mass, the ratio of the quantum dots, the polymer matrix, the antioxidant, the light stabilizer and the functional additive is 1 part: (0.05 parts to 2 parts): (1 part to 5 parts): (1 part to 8 parts): (1 part to 10 parts).

2. The ultraviolet conversion film according to claim 1, characterized in that: The quantum dots include one or more of cadmium-based quantum dots, sulfur-based quantum dots, perovskite quantum dots, carbon-based quantum dots, metal phosphide quantum dots, metal oxide quantum dots, metal nitride quantum dots, silicon-based quantum dots, and organic quantum dots; The general formula of the cadmium-based quantum dots is CdW, wherein W is selected from S 2- 、Se 2- 、Te 2- One or more of; The general formula of the sulfur-based quantum dots is M1 x S y , where M1 is selected as Zn 2+ 、Cd 2+ 、Ag + One or more of, x and y are determined by the method of balancing the chemical formula of sulfur-based quantum dots; The general formula of the perovskite quantum dot is ABR3, wherein A is selected from one or more of formamidinium ion, methylamine ion, and cesium ion; B is selected from Pb 2+ Sn 2+ 、Eu 2+ , Cu 2+ 、Ni 2+ One or more of; R is selected from one or more of halogen ions; The carbon-based quantum dots include carbon-based quantum dots composed of one or more elements selected from C, O, N and H; The general formula of the metal phosphide quantum dot is M2 x1 P y1 , wherein M2 is selected from In 3+ , Ga 3+ 、Zn 2+ , Cu 2+ One or more of, x1 and y1 are determined by a method of balancing the chemical formula of metal phosphide quantum dots; The general formula of the metal oxide quantum dot is M3 x2 O y2 , wherein M3 is selected from Cu 2+ 、Zn 2+ , Fe 3+ , Ba 2+ 、Ti + , Li + , Mn 3 + , Mn 4+ One or more of, x2 and y2 are determined by a method of balancing the chemical formula of metal oxide quantum dots; The general formula of the metal nitride quantum dot is M4 x3 N y3 , wherein M4 is selected from Ti 3+ 、Al 3+ , Ga 3+ , Fe 3+ , Fe 4+ One or more of, x3 and y3 are determined by a method of balancing the chemical formula of metal nitride quantum dots; The silicon-based quantum dots include one or more of intrinsic silicon-based quantum dots and doped silicon-based quantum dots; The organic quantum dots include one or more of conjugated polymer quantum dots, dendrimer quantum dots, and organic small molecular weight quantum dots; The size of the quantum dots is 3 nm to 30 nm.

3. The UV conversion film according to claim 1, characterized in that: The polymer matrix includes one or more of polyvinyl alcohol, polyethylene terephthalate, polycarbonate, polyethylene-polyvinyl acetate copolymer, ethylene and octene copolymer, polyvinyl butyral, polyvinylidene fluoride, polyvinyl acetate, cellulose acetate, polysulfone, aromatic polyamide, polyimide, polystyrene, polymethyl methacrylate, thermoplastic polyolefin, and polyurethane.

4. The ultraviolet conversion film according to claim 1, characterized in that: The antioxidant includes one or more of antioxidant 1010, antioxidant 1076, antioxidant 168, ethylenediaminetetraacetic acid, diphenylamine, and p-phenylenediamine.

5. The ultraviolet conversion adhesive film according to claim 1, characterized in that: The light stabilizer includes one or more of titanium dioxide, zinc oxide, nickel-dithiocarbamate complex, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, triphenyl phosphite, light stabilizer 622, BASF Tinuvin 770, BASF Tinuvin 622, and Chimassorb 944.

6. The ultraviolet conversion adhesive film according to claim 1, characterized in that: The functional additives include one or more of organic small molecule passivators, high molecular polymer passivators, surfactants, high molecular dispersants, amino acids and their derivatives, organic phosphonic acid compounds, conductive polymer additives, and small molecule hole transport material additives.

7. The ultraviolet conversion adhesive film according to claim 6, characterized in that: The organic small molecule passivator includes one or more of ethylenediaminetetraacetic acid, triethanolamine, acetylacetone, pyridine and aniline; The polymer passivator includes one or more of polyvinyl pyrrolidone, polystyrene, polyethylene glycol and polyacrylic acid; The surfactant includes one or more of sodium lauryl sulfate, cetyl trimethyl ammonium bromide, polyoxyethylene sorbitan monooleate, Triton X-100 and laureth-7; The polymer dispersant includes one or more of polycarboxylic acid sodium salt, polystyrene-maleic anhydride copolymer, sodium polyacrylate, polyvinyl butyral and polyamide-amine dendrimer; The amino acids and their derivatives include one or more of glycine, lysine, cysteine, glutamic acid and phenylalanine; The organic phosphonic acid compound includes one or more of aminotrimethylenephosphonic acid, ethylenediaminetetramethylenephosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, hydroxyethylidene diphosphonic acid and hexamethylenediaminetetramethylenephosphonic acid; The conductive polymer additive includes one or more of polyaniline, polythiophene, polypyrrole, poly(3,4-ethylenedioxythiophene) and poly(p-phenylene vinylene); The small molecule hole transport material additive includes one or more of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-di(1-naphthyl)-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, spiro-bifluorene-9,9'-bis(9-phenyl-9H-carbazole), 4-(diphenylamino)benzaldehyde and tris(4-bromophenyl)amine.

8. The method for preparing the ultraviolet conversion adhesive film according to any one of claims 1 to 7, characterized in that: The preparation method comprises mixing quantum dots, a polymer matrix, a light stabilizer, an antioxidant and a functional additive to form a film.

9. The preparation method according to claim 8, characterized in that: The film forming temperature is 140°C-200°C.

10. Use of the UV conversion adhesive film described in any one of claims 1 to 7 or the UV conversion adhesive film obtained by the preparation method described in any one of claims 8 to 9 as a cell packaging film for solar cells.

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