High-thermal-stability lead halide perovskite quantum dot, preparation method thereof and light conversion adhesive film

Abstract

The invention relates to the technical field of semiconductor materials, and particularly provides a high-thermal-stability lead halide perovskite quantum dot, a preparation method thereof and a light conversion adhesive film. The invention aims to solve the problems of poor thermal stability and limited application of lead halide perovskite quantum dots in the prior art. Therefore, the invention provides the lead halide perovskite quantum dot with high thermal stability, the lead halide perovskite quantum dot with high thermal stability is aromatic carboxylic acid-CsPbX3, and X is one or two of Cl, Br and I. According to the preparation method, the aromatic carboxylic acid is used for carrying out surface treatment on the lead halide perovskite quantum dots, so that the existence of halogen ion vacancies is reduced, and meanwhile, carboxyl is used for passivating surface lead bases, so that the stability of the lead halide perovskite quantum dots is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor materials, and specifically provides a lead halide perovskite quantum dot with high thermal stability, a preparation method thereof, and a light-converting adhesive film. Background Art

[0002] Due to their excellent optoelectronic properties, lead-halide perovskites have been widely applied in photovoltaic and optoelectronic fields, achieving groundbreaking research results. However, lead-halide perovskite CsPbBr3 quantum dots decompose in water and are extremely unstable, a significant constraint on their application. Therefore, enhancing the water stability of perovskite materials has become a research hotspot. Finding methods to prepare water-stable lead-halide perovskite quantum dots can stabilize the performance of lead-halide perovskite optoelectronic devices and expand their applications in fluorescent labeling for biological detection in aquatic environments, which is of great significance.

[0003] Currently, the existing preparation method of lead halide perovskite nanomaterials usually adopts solvent thermal synthesis, but the synthesized lead halide quantum dots decompose when exposed to water or ethanol and no longer emit light. Even in the air, they will be extremely unstable and age rapidly due to the presence of water vapor.

[0004] CN107117646A discloses a method for preparing a lead halide perovskite quantum dot material. The method comprises: adding Cs2CO3 to a reaction flask A, adding octadecene and oleic acid to the reaction flask A, passing argon through a three-necked flask A, and stirring the reaction flask A; adding PbBr2 to a reaction flask B, adding octadecene to the reaction flask B, passing argon through the reaction flask B, and stirring the reaction flask B; heating the reaction flask A to 140-160°C and the reaction flask B to 170-190°C; after the temperatures stabilize, maintaining the temperatures of the reaction flasks A and B for a specified time; after the insulation of the reaction flasks A and B is completed, taking the solution in the reaction flask A and adding it to the reaction flask B; allowing the reaction flask B to react for a specified time to generate the perovskite quantum dot material; and subjecting the perovskite quantum dot material to an ice bath, freezing, and drying to obtain a lead halide perovskite quantum dot material powder. This method can produce a lead halide perovskite quantum dot material that can still stably emit light in water and ethanol environments. However, due to the properties of lead halide perovskite ionic crystals, when affected by the heat generated by rising temperature, the ions in lead halide perovskite quantum dots are prone to migration, causing the collapse of their own structure; at the same time, there are high-density defects on the surface of lead halide perovskite quantum dots, and heat will increase the non-radiative recombination on the surface of the quantum dots, resulting in a decrease in the fluorescence efficiency of the quantum dots or even quenching, affecting the use of perovskite quantum dots.

[0005] Accordingly, this field requires a new technical solution to solve the above technical problems. Summary of the Invention

[0006] The present invention aims to solve the above technical problems, that is, to solve the problems of poor thermal stability and limited application of lead halide perovskite quantum dots in the prior art.

[0007] In a first aspect, the present invention provides a high thermal stability lead halide perovskite quantum dot, wherein the high thermal stability lead halide perovskite quantum dot is an aromatic carboxylic acid -CsPbX3, and X is one or two of Cl, Br, and I.

[0008] In the preferred technical solution of the above-mentioned high thermal stability lead halide perovskite quantum dots, the CsPbX3 is CsPbCl3, CsPbBr3, CsPbI3, CsPb(Cl n Br 1-n )3 or CsPb(Br n I 1-n )3, 0<n<1.

[0009] In the preferred technical solution of the above-mentioned high thermal stability lead halide perovskite quantum dots, the aromatic carboxylic acid is any one of benzoic acid, phenylacetic acid, phthalic acid or salicylic acid.

[0010] In a second aspect, the present invention provides a method for preparing the high thermal stability lead halide perovskite quantum dots, wherein the preparation method comprises:

[0011] Providing a CsPbX3 solution;

[0012] The aromatic carboxylic acid is dispersed in the CsPbX3 solution to obtain the product.

[0013] In the preferred technical solution of the above preparation method, the mass ratio of the aromatic carboxylic acid to CsPbX3 in the CsPbX3 solution is 1:(15-30).

[0014] In the preferred technical solution of the above preparation method, the concentration of the CsPbX3 solution is 5-10 mg / ml.

[0015] In a third aspect, the present invention provides a light-converting adhesive film, wherein the light-converting adhesive film comprises the high thermal stability lead halide perovskite quantum dots described in the first aspect or the high thermal stability lead halide perovskite quantum dots prepared by the preparation method described in the second aspect.

[0016] In the preferred technical solution of the above-mentioned light-converting adhesive film, the mass proportion of the high thermal stability lead halide perovskite quantum dots in the light-converting adhesive film is 1.5 to 4 wt%.

[0017] In the preferred technical solution of the above light-converting adhesive film, the light-converting adhesive film further includes substrate particles.

[0018] In the preferred technical solution of the above-mentioned light-converting adhesive film, the substrate particles include the following components:

[0019] The high thermal stability lead halide perovskite quantum dots, preparation method and light-converting adhesive film of the present application have the following technical effects:

[0020] 1. The present invention uses aromatic carboxylic acids to treat the surface of lead halide perovskite quantum dots to reduce the presence of halogen ion vacancies, and simultaneously uses carboxyl groups to passivate the surface lead groups to obtain an aromatic carboxylic acid - CsPbX3, which improves the thermal stability of lead halide perovskite quantum dots;

[0021] 2. During the preparation process of the light-converting adhesive film provided by the present invention, an appropriate amount of acid absorber is added to remove excess acid, thereby eliminating its impact on photovoltaic modules and reducing potential-induced degradation (PID). After high-temperature and high-humidity aging tests, photovoltaic modules made with this light-converting adhesive film maintained power levels exceeding 90% of the original modules, with significantly reduced degradation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0023] Figure 1 This is the process flow for preparing high thermal stability lead halide perovskite quantum dots of the present invention;

[0024] Figure 2 This is a comparison chart of the changes in fluorescence efficiency of the quantum dots in Example 1 and Comparative Example 1 before and after being placed in a thermal environment of 85°C. DETAILED DESCRIPTION

[0025] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0026] In this application, the term "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0027] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0028] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. Some or all of the steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0029] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0030] The weights of the relevant components mentioned in the examples of this application may not only refer to the specific content of each component, but also represent the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the examples of this application, it is within the scope disclosed in the examples of this application. Specifically, the mass described in the examples of this application may be a mass unit known in the chemical industry, such as μg, mg, g, kg, etc.

[0031] The terms "first" and "second" are used solely for descriptive purposes to distinguish objects, such as substances, from one another and should not be understood to indicate or imply relative importance or to implicitly specify the quantity of the technical features being referred to. For example, without departing from the scope of the embodiments of this application, a first XX may also be referred to as a second XX, and similarly, a second XX may also be referred to as a first XX. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of such features.

[0032] The experimental methods in the following examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples are commercially available unless otherwise specified.

[0033] Based on the problems of poor thermal stability and limited application of lead halide perovskite quantum dots in the prior art as pointed out in the background art, the present invention provides lead halide perovskite quantum dots with high thermal stability, a preparation method thereof, and a light-converting adhesive film. The lead halide perovskite quantum dots are surface-treated with aromatic carboxylic acids to reduce the presence of halide ion vacancies. At the same time, the surface lead groups are passivated by carboxyl groups, thereby improving the thermal stability of the lead halide perovskite quantum dots.

[0034] Specifically, the present invention provides a high thermal stability lead halide perovskite quantum dot in a first aspect, wherein the high thermal stability lead halide perovskite quantum dot is an aromatic carboxylic acid -CsPbX3, and X is one or two of Cl, Br, and I.

[0035] Lead halide perovskite quantum dots have the advantages of high absorption efficiency, narrow half-width, high luminous efficiency, and tunable wavelength, but the poor thermal stability of lead halide perovskite greatly limits its application. The inventors have found that the fundamental reason for the poor thermal stability of lead halide perovskite quantum dots is their abundant surface defects (lead ion vacancies and halide ion vacancies). The present invention uses aromatic carboxylic acids to treat the surface of lead halide perovskite quantum dots, reducing the presence of halide ion vacancies, and at the same time passivating the surface lead groups with carboxyl groups to obtain an aromatic carboxylic acid-CsPbX3, which improves the thermal stability of lead halide perovskite quantum dots.

[0036] It should be noted that the high thermal stability lead halide perovskite quantum dots of the present invention are stored and used in a liquid state, specifically, they are dispersed in a hexane solution and stored for standby use.

[0037] In some specific embodiments, the CsPbX3 is CsPbCl3, CsPbBr3, CsPbI3, CsPb(Cl n Br 1-n )3 or CsPb(Br n I 1-n )3, 0<n<1.

[0038] In some specific embodiments, the aromatic carboxylic acid is any one of benzoic acid, phenylacetic acid, phthalic acid or salicylic acid.

[0039] In a second aspect, the present invention provides a method for preparing the high thermal stability lead halide perovskite quantum dots. Figure 1 As shown, the preparation method comprises:

[0040] S1, providing CsPbX3 solution;

[0041] S2. Dispersing the aromatic carboxylic acid into the CsPbX3 solution to obtain.

[0042] In some specific embodiments, the mass ratio of the aromatic carboxylic acid to CsPbX3 in the CsPbX3 solution is 1:(15-30).

[0043] In some specific embodiments, the concentration of the CsPbX3 solution is 5 to 10 mg / ml.

[0044] It should be noted that the CsPbX3 solution described in the present invention is a CsPbX3 hexane solution, which can be obtained by a method commonly used in the art, for example, by hot injection.

[0045] Specifically, in some embodiments, the CsPbX3 hexane solution can be obtained by a method comprising the following steps:

[0046] S11, preparation of Cs-precursor solution;

[0047] S12. Preparation of CsPbX3 hexane solution.

[0048] In some specific embodiments, the Cs-precursor solution is prepared by dissolving Cs2CO3 in a mixed solution of octadecene and oleic acid, evacuating the solution at a certain temperature for a period of time, heating the solution in an Ar environment, and stirring the solution until the solid is completely dissolved to obtain the Cs-precursor solution, which is then cooled for later use.

[0049] In some specific embodiments, in the preparation of the Cs-precursor solution, the vacuuming at a certain temperature for a period of time is vacuuming at 120-130° C. for 30 minutes to 1 hour. For example, in some embodiments, the vacuuming is performed at 120° C. for 30 minutes; in some embodiments, the vacuuming is performed at 120° C. for 1 hour; and in some embodiments, the vacuuming is performed at 130° C. for 30 minutes.

[0050] In some specific embodiments, in the preparation of the Cs-precursor solution, the temperature in the Ar environment is raised to 150-180° C. For example, it can be 150° C., 160° C., 180° C., 170° C., or any value within the range.

[0051] In some specific embodiments, in the preparation of the Cs-precursor solution, the temperature is lowered to 80-100° C. For example, the temperature may be lowered to 80° C., 90° C., 100° C., or any value within the range.

[0052] In some specific embodiments, the CsPbX3 hexane solution is prepared as follows: PbX2 is dissolved in a mixed solution of octadecene, oleic acid and oleylamine, vacuumed at a certain temperature for a period of time, heated in an Ar environment, and quickly injected with the Cs-precursor solution. After reacting for a period of time, it is cooled, cooled to room temperature and centrifuged to precipitate. After removing the supernatant, hexane is added to dissolve it again to obtain the CsPbX3 hexane solution.

[0053] In some specific embodiments, in the preparation of the CsPbX3 hexane solution, the vacuuming at a certain temperature for a period of time is vacuuming at 120-130°C for 30 minutes to 1 hour. For example, in some embodiments, the vacuuming is performed at 120°C for 30 minutes; in some embodiments, the vacuuming is performed at 120°C for 1 hour; and in some embodiments, the vacuuming is performed at 130°C for 30 minutes.

[0054] In some specific embodiments, in the preparation of the CsPbX3 hexane solution, the temperature in the Ar environment is raised to 150-190° C. For example, it can be 150° C., 160° C., 180° C., 170° C., 190° C., or any value within the range.

[0055] In some specific embodiments, in step S2, the step of dispersing the aromatic carboxylic acid into the CsPbX3 solution is:

[0056] Add the aromatic carboxylic acid to the CsPbX3 hexane solution and stir at room temperature until the aromatic carboxylic acid is completely dispersed in the solution.

[0057] In some specific embodiments, the stirring time is 1 hour.

[0058] The present invention provides a light-converting adhesive film in a third aspect, wherein the light-converting adhesive film comprises the high thermal stability lead halide perovskite quantum dots described in the first aspect or the high thermal stability lead halide perovskite quantum dots prepared by the preparation method described in the second aspect.

[0059] In some specific embodiments, the mass percentage of the high thermal stability lead halide perovskite quantum dots in the light-converting adhesive film is 1.5-4 wt %, for example, 1.5 wt %, 2 wt %, 2.5 wt %, 3 wt %, 3.5 wt %, 4 wt %, or any value within the range.

[0060] It should be noted that, in the present invention, the mass of the high thermal stability lead halide perovskite quantum dots is calculated based on the amount of the high thermal stability lead halide perovskite quantum dot solution.

[0061] In some embodiments, the high thermal stability lead halide perovskite quantum dot solution is the high thermal stability lead halide perovskite quantum dot hexane solution.

[0062] In the preferred technical solution of the above light-converting adhesive film, the light-converting adhesive film further includes substrate particles.

[0063] In the preferred technical solution of the above-mentioned light-converting adhesive film, the substrate particles include the following components:

[0064] This invention utilizes aromatic carboxylic acids to stabilize lead halide perovskite quantum dots. Considering the destructive effects of acids on quantum dots and the film, an appropriate amount of an acid absorber is added during the film preparation process to remove excess acid. Photovoltaic modules fabricated from this light-converting film have undergone high-temperature and high-humidity aging testing, demonstrating that power output remains above 90% of the original modules, with significantly reduced attenuation.

[0065] In some embodiments, the blank particles are one of EVA or POE.

[0066] In some specific embodiments, the cross-linking agent is one or more of tert-butyl peroxy-2-ethylhexane carbonate, 1,1-di-tert-butyl peroxy-3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di(tert-butyl peroxy)hexane, and tert-amyl peroxy(2-ethylhexyl)carbonate.

[0067] In some specific embodiments, the auxiliary cross-linking agent is one or more of triallyl isocyanurate, trimethylolpropane triacrylate, triallyl cyanurate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane triacrylate.

[0068] In some specific embodiments, the coupling agent is one or more of γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltri(β-methoxyethoxy)silane, vinyltriethoxysilane, and γ-glycidoxypropyltrimethoxysilane.

[0069] In some specific embodiments, the antioxidant is one or more of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-thiobis[ethyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], tris[2,4-di-tert-butylphenyl] phosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, tris(nonylphenyl) phosphite, and triphenyl phosphite.

[0070] In some specific embodiments, the light stabilizer is one or more of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinethanol) succinate, and bis(1,2,2,6,6-pentamethylpiperidinol) sebacate.

[0071] In some specific embodiments, the acid scavenger is one or both of Mg(OH)2 and MgO.

[0072] In this invention, considering the destructive effects of acids on quantum dots and films, an appropriate amount of an acid absorber is added during the preparation of the light-converting film to remove excess acid. Photovoltaic modules fabricated with this light-converting film have undergone high-temperature and high-humidity aging tests, and their power remains above 90% of the original modules, with significantly reduced attenuation.

[0073] It should be noted that the light-converting adhesive film can be prepared by a commonly used method in the art, and the present invention does not make any specific limitation thereto. For example, it can be prepared by a method comprising the following steps:

[0074] 1. Preparation of substrate particles

[0075] Blank particles, a cross-linking agent, a co-cross-linking agent, a coupling agent, an antioxidant, a light stabilizer, and an acid absorbent are uniformly mixed, and then melted, extruded, and granulated to obtain substrate particles;

[0076] 2. Preparation of light-converting film

[0077] The high thermal stability lead halide perovskite quantum dots are evenly mixed with substrate particles, and then melt-extruded and cast into a film to obtain the light-converting adhesive film.

[0078] In some specific embodiments, the high thermal stability lead halide perovskite quantum dots are mixed with the substrate particles in the form of a high thermal stability lead halide perovskite quantum dot hexane solution.

[0079] The following describes in detail the high thermal stability lead halide perovskite quantum dots, preparation method and light-converting adhesive film of the present invention through several specific embodiments.

[0080] Example 1

[0081] This embodiment provides a high thermal stability lead halide perovskite quantum dot, a preparation method and a light-converting adhesive film.

[0082] [High thermal stability lead halide perovskite quantum dots]

[0083] The high thermal stability lead halide perovskite quantum dots provided in this embodiment are benzoic acid-CsPbBr3.

[0084] Its preparation method is:

[0085] S1. Provide CsPbBr3 hexane solution

[0086] Preparation of Cs-precursor solution: 3.258 g of cesium carbonate (Cs2CO3) was dissolved in a mixed solution of 20 ml of octadecene (ODE) and 20 ml of oleic acid (OA), vacuumed at 120 °C for 30 min, heated to 150 °C in an Ar environment, stirred until the solid was completely dissolved to obtain a Cs-precursor solution, and cooled to 80 °C for use.

[0087] Preparation of CsPbBr3 hexane solution: 3.67g PbBr2 was dissolved in a mixed solution of ODE, OA and oleylamine (OAm) with a volume ratio of 10:1:1 (total 60ml), vacuumed at 120℃ for 30min, heated to 180℃ in an Ar environment, and quickly injected with 8ml Cs-precursor solution. After reacting for 5s, it was cooled in an ice bath, cooled to room temperature and centrifuged to precipitate. After removing the supernatant, 500ml hexane was added and redissolved to obtain a CsPbBr3 hexane solution with a concentration of 10mg / ml.

[0088] S2. Disperse aromatic carboxylic acid (benzoic acid) into CsPbBr3 hexane solution

[0089] Add 0.25g of benzoic acid to 500ml of the CsPbBr3 hexane solution and stir at room temperature for 1 hour until the benzoic acid is completely dispersed in the solution. Stop stirring, add excess ethyl acetate, and centrifuge twice to precipitate. Finally, disperse the resulting precipitate in the hexane solution to obtain a benzoic acid-CsPbBr3 hexane solution, which will be used as the light conversion agent in the subsequent light conversion film.

[0090] [Light-transfer film]

[0091] This embodiment further provides a light-converting adhesive film, wherein the raw materials for preparing the light-converting adhesive film include substrate particles and benzoic acid-CsPbBr3 hexane solution, and the mass proportion of the benzoic acid-CsPbBr3 hexane solution in the light-converting adhesive film is 2 wt%.

[0092] The components and dosage of the substrate particles are as follows:

[0093] The method for preparing the light-converting adhesive film of this embodiment comprises the following steps:

[0094] 1. Preparation of substrate particles

[0095] The blank particles, cross-linking agent, auxiliary cross-linking agent, coupling agent, antioxidant, light stabilizer and acid absorber are mixed uniformly according to the above amounts, poured into an extruder for extrusion and granulation, and the temperatures of the feed section, extrusion section and discharge section of the granulator are set to 110° C., 115° C. and 120° C., respectively. After melting, extrusion, wire drawing and pelletizing, substrate particles with a particle size of 2 mm are finally obtained.

[0096] 2. Preparation of light-converting film

[0097] Take 20g of benzoic acid-CsPbBr3 hexane solution and mix it evenly with 980g of substrate particles. After mixing evenly, pour it into the extruder. After heating to 140°C, the molten raw material is injected into the mold and cast into the film to finally obtain a light-converting film with a thickness of 0.5mm.

[0098] Example 2

[0099] This embodiment provides a high thermal stability lead halide perovskite quantum dot, a preparation method and a light-converting adhesive film.

[0100] [High thermal stability lead halide perovskite quantum dots]

[0101] The high thermal stability lead halide perovskite quantum dots provided in this embodiment are phenylacetic acid-CsPbCl3.

[0102] Its preparation method is:

[0103] S1. Provide CsPbCl3 hexane solution

[0104] Preparation of Cs-precursor: Dissolve 4 g of cesium carbonate (Cs2CO3) in a mixed solution of 50 ml of octadecene (ODE) and 50 ml of oleic acid (OA), evacuate at 120°C for 30 min, heat to 160°C in an Ar environment, stir until the solid is completely dissolved to obtain a Cs-precursor solution, and cool to 100°C for use.

[0105] Preparation of CsPbCl3 hexane solution: 2.78g PbCl2 was dissolved in a mixed solution of ODE, OA and oleylamine (OAm) with a volume ratio of 8:1:1 (total 50ml), vacuumed at 110℃ for 30min, heated to 190℃ in an Ar environment, and 6ml Cs-precursor solution was quickly injected. After reacting for 10s, it was cooled in an ice bath, cooled to room temperature and centrifuged to precipitate. After removing the supernatant, 800ml hexane was added and redissolved to obtain a CsPbCl3 hexane solution with a concentration of 5mg / ml.

[0106] S2. Disperse aromatic carboxylic acid (phenylacetic acid) into CsPbCl3 hexane solution

[0107] Add 0.20 g of phenylacetic acid to 600 ml of the above CsPbCl3 hexane solution and stir at room temperature for 1 hour until the phenylacetic acid is completely dispersed in the solution. Stop stirring, add excess ethyl acetate and centrifuge twice to precipitate. The resulting precipitate is finally dispersed in the hexane solution to obtain a phenylacetic acid-CsPbCl3 hexane solution, which is used as a light conversion agent in subsequent light conversion film.

[0108] [Light-transfer film]

[0109] This embodiment further provides a light-converting adhesive film. The raw materials for preparing the light-converting adhesive film include substrate particles and phenylacetic acid-CsPbCl3 hexane solution. The mass proportion of the phenylacetic acid-CsPbCl3 hexane solution in the light-converting adhesive film is 1.5 wt%.

[0110] The components and dosage of the substrate particles are as follows:

[0111] The method for preparing the light-converting adhesive film of this embodiment comprises the following steps:

[0112] 1. Preparation of substrate particles

[0113] Same as Example 1.

[0114] 2. Preparation of light-converting film

[0115] Take 15g of phenylacetic acid-CsPbCl3 hexane solution and mix it evenly with 985g of substrate particles. After mixing evenly, pour it into the extruder. After heating to 140°C, the molten raw material is injected into the mold and cast into a film with a thickness of 0.4mm.

[0116] Example 3

[0117] This embodiment provides a high thermal stability lead halide perovskite quantum dot, a preparation method and a light-converting adhesive film.

[0118] [High thermal stability lead halide perovskite quantum dots]

[0119] The high thermal stability lead halide perovskite quantum dots provided in this embodiment are phthalic acid-CsPbI3.

[0120] Its preparation method is:

[0121] S1. Provide CsPbI3 hexane solution

[0122] Preparation of Cs-precursor solution: Dissolve 2 g of cesium carbonate (Cs2CO3) in a mixed solution of 100 ml of octadecene (ODE) and 10 ml of oleic acid (OA), evacuate at 120 ° C for 1 h, heat to 180 ° C in an Ar environment, stir until the solid is completely dissolved to obtain a Cs-precursor solution, and cool to 100 ° C for use.

[0123] Preparation of CsPbI3 hexane solution: 3.4g PbI2 was dissolved in a mixed solution of ODE, OA and oleylamine (OAm) with a volume ratio of 10:1:1 (total 240ml), vacuumed at 120℃ for 1h, heated to 180℃ in an Ar environment, and 20ml Cs-precursor was quickly injected. After reacting for 5s, it was cooled in an ice bath, cooled to room temperature and centrifuged to precipitate. After removing the supernatant, 500ml hexane was added and redissolved to obtain a CsPbI3 hexane solution with a concentration of 8mg / ml.

[0124] S2. Disperse aromatic carboxylic acid (phthalic acid) into CsPbI3 hexane solution

[0125] Add 0.16 g of phthalic acid to 500 ml of the above-mentioned CsPbI3 hexane solution and stir at room temperature for 1 hour until the phthalic acid is completely dispersed in the solution. Stop stirring, add excess ethyl acetate and centrifuge twice. The obtained precipitate is finally dispersed in the hexane solution to obtain a phthalic acid-CsPbI3 hexane solution, which is used as a light conversion agent in the subsequent light conversion film.

[0126] [Light-transfer film]

[0127] This embodiment further provides a light-converting adhesive film. The raw materials for preparing the light-converting adhesive film include substrate particles and phthalic acid-CsPbI3 hexane solution. The mass proportion of the phthalic acid-CsPbI3 hexane solution in the light-converting adhesive film is 4 wt%.

[0128] The components and dosage of the substrate particles are as follows:

[0129] The method for preparing the light-converting adhesive film of this embodiment comprises the following steps:

[0130] 1. Preparation of substrate particles

[0131] Same as Example 1.

[0132] 2. Preparation of light-converting film

[0133] Take 40g of phthalic acid-CsPbI3 hexane solution and mix it evenly with 960g of substrate particles. After mixing evenly, pour it into the extruder. After heating to 140℃, the molten raw material is injected into the mold and cast into the film to finally obtain a light-converting film with a thickness of 0.3mm.

[0134] Example 4

[0135] This embodiment provides a high thermal stability lead halide perovskite quantum dot, a preparation method and a light-converting adhesive film.

[0136] [High thermal stability lead halide perovskite quantum dots]

[0137] The high thermal stability lead halide perovskite quantum dots provided in this embodiment are salicylic acid-CsPbCl 1.5 Br 1.5 .

[0138] Its preparation method is:

[0139] S1. Provide CsPbCl 1.5 Br 1.5 Hexane solution

[0140] Preparation of Cs-precursor solution: 3.2 g of cesium carbonate (Cs2CO3) was dissolved in a mixed solution of 120 ml of octadecene (ODE) and 10 ml of oleic acid (OA), vacuumed at 130 °C for 30 min, heated to 150 °C in an Ar environment, stirred until the solid was completely dissolved to obtain a Cs-precursor solution, and cooled to 90 °C for use.

[0141] CsPbCl 1.5 Br 1.5 Preparation of hexane solution: 1.8 g PbBr2 and 1.4 g PbCl2 were dissolved in a mixed solution of ODE, OA, and oleylamine (OAm) with a volume ratio of 10:1:1 (total 60 ml). The mixture was vacuumed at 120 °C for 1 h, heated to 180 °C in an Ar atmosphere, and 18 ml of Cs-precursor solution was rapidly injected. After reacting for 5 seconds, the mixture was cooled in an ice bath, cooled to room temperature, and centrifuged. After removing the supernatant, 1000 ml of hexane was added and redissolved to obtain a CsPbCl solution with a concentration of 5 mg / ml. 1.5 Br 1.5 Hexane solution.

[0142] S2. Disperse aromatic carboxylic acid (salicylic acid) into CsPbCl 1.5 Br 1.5 Hexane solution

[0143] Add 0.2g salicylic acid to 1200ml of the above CsPbCl 1.5 Br 1.5 The solution was stirred at room temperature for 1 h until salicylic acid was completely dispersed in the solution. Stirring was stopped, excess ethyl acetate was added and centrifuged twice. The obtained precipitate was finally dispersed in the hexane solution to obtain salicylic acid-CsPbCl 1.5 Br 1.5The hexane solution is used as the light-converting agent in the subsequent light-converting film.

[0144] [Light-transfer film]

[0145] This embodiment further provides a light-converting adhesive film, the raw materials for preparing the light-converting adhesive film include substrate particles and salicylic acid-CsPbCl 1.5 Br 1.5 , the salicylic acid-CsPbCl 1.5 Br 1.5 The mass proportion of the hexane solution in the light conversion film is 3 wt %.

[0146] The components and dosage of the substrate particles are as follows:

[0147] The method for preparing the light-converting adhesive film of this embodiment comprises the following steps:

[0148] 1. Preparation of substrate particles

[0149] Same as Example 1.

[0150] 2. Preparation of light-converting film

[0151] Take 30g of salicylic acid-CsPbCl 1.5 Br 1.5 The hexane solution was mixed evenly with 970 g of substrate particles and poured into an extruder. After the temperature was raised to 140° C., the molten raw material was injected into a mold and cast to obtain a light-converting film with a thickness of 0.5 mm.

[0152] Example 5

[0153] This embodiment provides a high thermal stability lead halide perovskite quantum dot, a preparation method and a light-converting adhesive film.

[0154] [High thermal stability lead halide perovskite quantum dots]

[0155] The high thermal stability lead halide perovskite quantum dots provided in this embodiment are benzoic acid-CsPbBr2I.

[0156] Its preparation method is:

[0157] S1. Provide CsPbBr2I hexane solution

[0158] Preparation of Cs-precursor solution: Dissolve 2.7 g of cesium carbonate (Cs2CO3) in a mixed solution of 50 ml of octadecene (ODE) and 10 ml of oleic acid (OA), evacuate at 120 ° C for 30 min, heat to 170 ° C in an Ar environment, stir until the solid is completely dissolved to obtain a Cs-precursor solution, and cool to 100 ° C for use.

[0159] Preparation of CsPbBr2I hexane solution: 2.51g PbBr2 and 1.23g PbCl2 were dissolved in a mixed solution of ODE, OA and oleylamine (OAm) with a volume ratio of 10:1:1 (total 120ml), vacuumed at 120℃ for 30min, heated to 190℃ in an Ar environment, and 12ml Cs-precursor solution was quickly injected. After reacting for 5s, the mixture was cooled in an ice bath, cooled to room temperature and centrifuged to precipitate. After removing the supernatant, 500ml hexane was added and redissolved to obtain a CsPbBr2I hexane solution with a concentration of 8mg / ml.

[0160] S2. Disperse aromatic carboxylic acid (benzoic acid) into CsPbBr2I hexane solution

[0161] Add 0.25 g of benzoic acid to 625 ml of the above CsPbBr2I hexane solution and stir at room temperature for 1 hour until the benzoic acid is completely dispersed in the solution. Stop stirring, add excess ethyl acetate and centrifuge twice. The resulting precipitate is finally dispersed in the hexane solution to obtain a benzoic acid-CsPbBr2I hexane solution, which can be used as a light conversion agent in subsequent light conversion adhesive films.

[0162] [Light-transfer film]

[0163] This embodiment further provides a light-converting adhesive film. The raw materials for preparing the light-converting adhesive film include substrate particles and benzoic acid-CsPbBr2I hexane solution. The mass proportion of the benzoic acid-CsPbBr2I hexane solution in the light-converting adhesive film is 3.5 wt%.

[0164] The components and dosage of the substrate particles are as follows:

[0165] The method for preparing the light-converting adhesive film of this embodiment comprises the following steps:

[0166] 1. Preparation of substrate particles

[0167] Same as Example 1.

[0168] 2. Preparation of light-converting film

[0169] Take 35g of benzoic acid-CsPbBr2I hexane solution and mix it evenly with 965g of substrate particles. After mixing evenly, pour it into the extruder. After heating to 140℃, the molten raw material is injected into the mold and cast into the film to finally obtain a light-converting film with a thickness of 0.4mm.

[0170] Test Example 1

[0171] This test example investigates the thermal stability of lead halide perovskite quantum dots before and after treatment with aromatic carboxylic acid in various embodiments of the present invention.

[0172] Test method: Take the CsPbBr3 quantum dots and benzoic acid-CsPbBr3 quantum dots obtained before and after adding benzoic acid in Example 1, and test the fluorescence quantum efficiency (PL) before and after 2 hours in a hot environment of 85°C. The test is carried out in accordance with the national standard GB / T44454-2024. The results are shown in Table 1 and Figure 1 shown.

[0173] Table 1 quantum dots PL before placement (%) PL after placement (%) <![CDATA[CsPbBr3]]> 95.4 22.28 <![CDATA[Benzoic acid-CsPbBr3]]> 94.64 90.27

[0174] The results showed that after 2 hours at 85°C, the fluorescence efficiency of benzoic acid-treated CsPbBr3 quantum dots remained unchanged, while the efficiency of untreated CsPbBr3 quantum dots decreased from 95.4% to 22.28%, indicating a significant improvement in the thermal stability of benzoic acid-CsPbBr3 quantum dots.

[0175] The thermal stability of lead halide perovskite quantum dots before and after treatment with aromatic carboxylic acid in other embodiments of the present invention was also investigated, and the results are shown in Table 2:

[0176] Table 2

[0177] From the results in Table 2, it can be seen that the thermal stability of lead halide perovskite quantum dots treated with aromatic carboxylic acid is significantly improved.

[0178] Test Example 2

[0179] This test example investigates the wet-heat aging stability of light-converting adhesive films made from lead halide perovskite quantum dots before and after treatment with aromatic carboxylic acid according to various embodiments of the present invention when applied to photovoltaic modules.

[0180] Test method:

[0181] Test sample 1: light-converting adhesive film prepared in Example 1;

[0182] Control sample 1: a light-conversion adhesive film prepared using the lead halide perovskite quantum dots in Example 1 without the treatment in step S2, and using the components and preparation method of the light-conversion adhesive film in Example 1;

[0183] Test sample 2: light-converting adhesive film prepared in Example 2;

[0184] Control sample 2: The lead halide perovskite quantum dots not treated in step S2 in Example 2 were used to prepare a light-converting adhesive film according to the composition and preparation method of the light-converting adhesive film in Example 2;

[0185] Test sample 3: light-converting adhesive film prepared in Example 3;

[0186] Control sample 3: a light-conversion adhesive film prepared using the lead halide perovskite quantum dots in Example 3 without the treatment in step S2, and using the components and preparation method of the light-conversion adhesive film in Example 3;

[0187] Test sample 4: light-converting adhesive film prepared in Example 4;

[0188] Control sample 4: a light-conversion adhesive film prepared using the lead halide perovskite quantum dots in Example 4 without the treatment in step S2, and using the components and preparation method of the light-conversion adhesive film in Example 4;

[0189] Test sample 5: light-converting adhesive film prepared in Example 5;

[0190] Control sample 5: a light-conversion adhesive film prepared using the lead halide perovskite quantum dots not treated in step S2 in Example 5 and the components and preparation method of the light-conversion adhesive film in Example 5;

[0191] After stacking photovoltaic glass, light-converting film, solar cell, encapsulation film and lower photovoltaic glass in the order of bottom to top, the photovoltaic glass is placed in a vacuum laminator. After vacuuming for 10 minutes, the temperature is raised to 120°C and laminated at a pressure of 25 MPa to obtain a photovoltaic module.

[0192] Each light-converting film sample was laminated to form a photovoltaic module. The initial module power and the power after 1000 hours of DH testing were measured, and the attenuation rate was calculated and compared. The PV module damp heat aging test was conducted in accordance with IEC61215-2:2021. DH stands for high-temperature, high-humidity aging. The test was conducted at a temperature of 85°C and a humidity of 85%. The power generation of the module was measured after 1000 hours of DH. Attenuation represents the power loss of the module after 1000 hours of DH aging.

[0193] The test results are shown in Table 3:

[0194] Table 3 Module initial power (W) DH1000h power (W) attenuation(%) Test sample 1 414.93 379.67 8.50 Control sample 1 411.87 74.13 82.00 Test sample 2 404.11 366.94 9.20 Control sample 2 408.35 49.28 87.93 Test sample 3 396.82 359.04 9.52 Control sample 3 401.76 39.69 90.12 Test sample 4 410.38 375.37 8.53 Control sample 4 409.26 61.79 84.90 Test sample 5 395.56 361.10 8.71 Control sample 5 392.24 55.77 85.78

[0195] It can be seen from the results in Table 3 above that compared with the photovoltaic modules made of the light-converting adhesive film made of lead halide perovskite quantum dots that have not been treated with aromatic carboxylic acid in each embodiment, the stability of the photovoltaic modules made of the light-converting adhesive film made of lead halide perovskite quantum dots that have been treated with aromatic carboxylic acid in the present invention has been significantly improved. After high-temperature and high-humidity aging tests, the power of the prepared photovoltaic modules still remains above 90% of the original photovoltaic modules, and the attenuation is significantly reduced.

[0196] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A high thermal stability lead halide perovskite quantum dot, characterized in that The high thermal stability lead halide perovskite quantum dots are aromatic carboxylic acids - CsPbX3, where X is one or two of Cl, Br, and I.

2. The high thermal stability lead halide perovskite quantum dots according to claim 1, characterized in that The CsPbX3 is CsPbCl3, CsPbBr3, CsPbI3, CsPb(Cl n Br 1-n )3 or CsPb(Br n I 1-n )3, 0<n<1.

3. The high thermal stability lead halide perovskite quantum dots according to claim 1 or 2, characterized in that The aromatic carboxylic acid is any one of benzoic acid, phenylacetic acid, phthalic acid or salicylic acid.

4. A method for preparing lead halide perovskite quantum dots with high thermal stability, characterized in that: The preparation method comprises: Providing a CsPbX3 solution; The aromatic carboxylic acid is dispersed in the CsPbX3 solution to obtain the product.

5. The preparation method according to claim 4, characterized in that The mass ratio of the aromatic carboxylic acid to CsPbX3 in the CsPbX3 solution is 1:(15-30).

6. The preparation method according to claim 4 or 5, characterized in that The concentration of the CsPbX3 solution is 5-10 mg / ml.

7. A light-converting film, characterized in that: The light-converting adhesive film comprises the high thermal stability lead halide perovskite quantum dots described in any one of claims 1-3 or the high thermal stability lead halide perovskite quantum dots prepared by the preparation method described in any one of claims 4-6.

8. The light-converting adhesive film according to claim 7, characterized in that: The mass proportion of the high thermal stability lead halide perovskite quantum dots in the light-converting adhesive film is 1.5-4wt%.

9. The light-converting adhesive film according to claim 8, characterized in that: The light-converting adhesive film further comprises substrate particles.

10. The light-converting adhesive film according to claim 9, characterized in that: The substrate particles include the following components:

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