Boron-containing quantum dot complex aggregate, preparation method therefor, and use thereof

Abstract

A boron-containing quantum dot complex aggregate, a preparation method therefor, and a use thereof. The boron-containing quantum dot complex aggregate comprises a tri-coordinated boron-containing quantum dot complex and tetra-coordinated boron-containing quantum dot complex conforming to formulas I and II and formed by means of chemical bonding of a boron-containing compound to a quantum dot. The boron-containing compound and the quantum dot in the tri-coordinated boron-containing quantum dot complex are covalently bonded, and the boron-containing compound and the quantum dot in the tetra-coordinated boron-containing quantum dot complex are coordinately bonded. The proportion of X-B coordination bonds in the boron-containing quantum dot complex aggregate to the sum of the numbers of X-B covalent bonds and X-B coordination bonds is 0.10-50%. The boron-containing quantum dot complex can exhibit both relatively strong binding ability and oxidation resistance, has good heat resistance, and is conducive to improving the stability of quantum dots while ensuring excellent optical performance and effectively avoiding the occurrence of black and yellow spots.

Description

A boron-containing quantum dot composite aggregate, its preparation method and application Technical Field

[0001] This disclosure belongs to the field of quantum dot technology, specifically relating to a boron-containing quantum dot composite aggregate, its preparation method, and its application. Background Technology

[0002] Quantum dots (QDs) are a class of crystalline nanoparticles exhibiting size-dependent properties due to the quantum confinement effect of electronic states. Because of their excellent luminescent properties (tunable emission wavelength, high quantum yield, and narrow and symmetrical emission spectrum), they have broad application prospects in display, lighting, solar energy, and biomedicine fields. Currently, the application of quantum dot photoluminescence technology in LCD backlighting is maturing, and different embedding schemes such as QD on chip, QD on edge, QD on surface, and QD on plate have been developed for various backlight structures. However, the stability of quantum dots remains one of the most significant obstacles to their application in LCDs.

[0003] Quantum dots typically consist of an inorganic core-shell or bare core and surface ligands. As a nanomaterial (with particle sizes generally between 1-30 nm), due to their large specific surface area, surface atoms readily react with water and oxygen to form defects, causing a significant decrease in fluorescence. The surface ligands of quantum dots bind to their inorganic surface, reducing the number of surface defect states caused by dangling bonds and simultaneously providing colloidal stability. Therefore, surface ligands play a dominant role in maintaining the colloidal properties of quantum dots and passivating surface defects.

[0004] Quantum dot surface ligands can be classified into three types (Owen J. The coordination chemistry of nanocrystal surfaces. Science, 2015, 347:614-615): such as L-type ligands (RNH2 and PR3 types that provide two lone pairs of electrons), X-type ligands (carboxylate, phosphate, and Cl- types that provide one lone pair of electrons). -L-type and X-type ligands (long-chain carboxylates or phosphonates capable of accepting lone pairs of electrons) are generally considered to bind to cations on the quantum dot surface to protect metal cations (such as Zn, Cd, etc.); while Z-type ligands act as electron acceptors to bind to anions to protect anions (such as Se, S, etc.). (Z. Hens. From ligands to binding motifs and beyond; the enhanced versatility of nanocrystal surfaces. Dalton Trans., 2016, 45, 13277-13283). Nicholas Kirkwood et al., Journal of the American Chemical Society 2018 140(46), 15712-15723, found that the increase in band gap energy level caused by surface states is the main reason affecting the optical and electronic properties of quantum dots. The defect states of group II-VIA and group III-VA quantum dots are mainly caused by anions on the surface of the quantum dots. Using Z-type ligands (Lewis acids) can effectively passivate the defect states caused by anions, thereby improving the PLQY of quantum dots. Rahul Singh et al., ACS Applied Nano Materials 2022 5(12), 18014-18022, found that using Z-type ligands (ZnCl2, CdCl2, etc.) to treat the surface of CdSe / ZnS gradient alloy core-shell quantum dots confirmed that the Z-type ligands passivated the defect states of the quantum dots by bonding with unsaturated chalcogen atoms on the surface, and their PLQY and optical stability were significantly improved.

[0005] Currently, the strategy of using Z-type ligands to improve the optical performance and stability of quantum dots has become an indispensable means in the field of quantum dot applications. For example, US20190031952A1 and CN110205111A used organic zinc thiolates and metal thiolates to improve the optical performance and stability of quantum dot composites and their devices; CN115181561A used metal carboxylates and metal phosphonates to improve the stability of quantum dot composites and their devices; CN112480927A used metal halides and organic ligands to improve the stability of quantum dot materials; CN113366083A used Z-type ligand ZnCl2 to improve the optical performance and stability of quantum dot materials; CN113710773A used zinc dioleate and metal halides to improve the quantum yield of InP quantum dots; and CN114341312A used zinc acetate and zinc fluoride to treat InP / ZnSe and InP / ZnSe / ZnS quantum dots to improve their optical properties and stability.

[0006] All of the above patented technologies use metal salts, especially organometallic salts (mostly zinc salts) Z-type ligands and their complexes to improve the optical properties and stability of quantum dots. However, the use of such Z-type ligands has certain limitations, such as: organothiols have insufficient temperature resistance (<200℃) and are not suitable for high-temperature (210℃-270℃) melt extrusion processing of quantum dot diffusion plates; organocarboxylate salts and organophosphonates have poor dispersion in the processing of PS quantum dot diffusion plates and are prone to producing black and yellow spots on the plate surface.

[0007] Although quantum dots using boron-containing compounds as ligands have appeared in the existing technology, their optical properties and stability have not been studied in depth, making it difficult to meet the requirements of optical diffusion plates for high stability and heat resistance of quantum dots.

[0008] It should be noted that this part of the disclosure only provides background technology related to this disclosure, and does not necessarily constitute prior art or publicly known technology.

[0009] Summary of the Invention

[0010] The purpose of this disclosure is to overcome the shortcomings of existing quantum dot composites in terms of poor stability and heat resistance, and to provide a boron-containing quantum dot composite aggregate, its preparation method and application. This boron-containing quantum dot composite can balance strong binding ability and oxidation resistance, has good heat resistance, which is conducive to improving the stability of quantum dots, while ensuring excellent optical performance and effectively avoiding the appearance of black and yellow spots.

[0011] To achieve the above objectives, in a first aspect, this disclosure provides a boron-containing quantum dot complex aggregate comprising a three-coordinate boron-containing quantum dot complex and a four-coordinate boron-containing quantum dot complex formed by chemical bonding of a boron-containing compound to quantum dots. In the three-coordinate boron-containing quantum dot complex, the boron-containing compound is covalently bonded to the quantum dots, and in the four-coordinate boron-containing quantum dot complex, the boron-containing compound is coordinately bonded to the quantum dots. The proportion of the number of XB coordinate bonds in the boron-containing quantum dot complex aggregate to the sum of the number of XB covalent bonds and XB coordinate bonds is 0.10%-50%, where X is selected from X1, X2, X3, X4, X5, and X6. The general chemical formula of the three-coordinate boron-containing quantum dot complex is as shown in Formula 1 below, and the general chemical formula of the four-coordinate boron-containing quantum dot complex is as shown in Formula 2 below.

[0012] Where QD stands for quantum dot; R8, R9, R 10 R 11 R 12 R 13Each of the following groups is independently selected from alkoxy, hydrocarbon, substituted hydrocarbon, halogen, carboxyl, hydroxyl, aldehyde, ester, and amide groups. The substituents in the substituted hydrocarbon groups are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups. n1 = a natural number, n2 = a natural number. X1, X2, X3, X4, X5, and X6 are independently selected from group VIA, group VA, and group IVA elements, respectively.

[0013] In some preferred embodiments of this disclosure, the boron-containing quantum dot composite aggregate is a boron-containing quantum dot dispersion, wherein the boron content in the boron-containing quantum dot dispersion is 1000ppm-9000ppm.

[0014] In some preferred embodiments of this disclosure, the boron-containing quantum dot composite aggregate is a boron-containing quantum dot composite plate, and the boron content in the boron-containing quantum dot composite plate is 13ppm-1750ppm.

[0015] In some preferred embodiments of this disclosure, X1, X2, X3, X4, X5, and X6 are each independently selected from O, S, Se, Te, N, P, As, C, Si, and Ge.

[0016] In some preferred embodiments of this disclosure, X1, X2, X3, X4, X5, and X6 are each independently selected from O or S.

[0017] In some preferred embodiments of this disclosure, R8, R9, R 10 R 11 R 12 R 13 Each group is independently selected from alkoxy groups with 1-18 carbon atoms, hydrocarbon groups with 1-18 carbon atoms, substituted hydrocarbon groups with 1-18 carbon atoms, halogens, carboxyl groups, hydroxyl groups, aldehyde groups, ester groups, and amide groups; the hydrocarbon groups with 1-18 carbon atoms are selected from alkyl groups with 1-18 carbon atoms, aryl groups with 6-18 carbon atoms, alkenyl groups with 2-18 carbon atoms, and alkynyl groups with 2-18 carbon atoms.

[0018] In some preferred embodiments of this disclosure, R8, R9, R 10 R 11 R 12 R 13 Each of the following groups is independently selected from alkoxy groups having 1-18 carbon atoms, alkyl groups having 1-18 carbon atoms, aryl or substituted aryl groups having 6-18 carbon atoms, and hydroxyl groups; wherein the substituent group in the substituted aryl group having 6-18 carbon atoms is selected from at least one of alkyl, halogen, hydroxyalkyl, alkoxy, halogen, carboxyl, and aldehyde groups.

[0019] In some preferred embodiments of this disclosure, R8 and R9 are each independently selected from hydroxyl, alkoxy with 1-18 carbon atoms, alkyl with 1-18 carbon atoms, aryl or substituted aryl with 6-18 carbon atoms, wherein R8 or R9 is selected from substituted aryl with 6-18 carbon atoms, and the substituent group in the substituted aryl is selected from at least one of alkyl, hydroxyalkyl and halogen.

[0020] R 10 R 11 R 12 R 13 Each of the following groups is independently selected from hydroxyl, alkoxy group with 1-18 carbon atoms, alkyl group with 1-18 carbon atoms, and aryl or substituted aryl group with 6-18 carbon atoms, wherein R 10 R 11 R 12 Or R 13 If the substituted aryl group is selected from substituted aryl groups having 6-18 carbon atoms, the substituent group in the substituted aryl group is selected from at least one of alkoxy, hydroxyalkyl, alkyl, and halogen. In some preferred embodiments of this disclosure, the tricoordinate boron-containing quantum dot complex is selected from: At least one of them.

[0021] In some preferred embodiments of this disclosure, the four-coordinate boron-containing quantum dot complex is selected from: At least one of them.

[0022] In some preferred embodiments of this disclosure, the quantum dot has a bare core structure, and the surface of the bare core structure has at least one of group IVA atoms, group VA anions, and group VIA anions.

[0023] In some preferred embodiments of this disclosure, the quantum dot has a core-shell structure, and the shell surface of the core-shell structure contains at least one of group IVA atoms, group VA anions, and group VIA anions.

[0024] Secondly, this disclosure provides a method for preparing a boron-containing quantum dot dispersion, comprising the following steps:

[0025] S1. Prepare boron-containing compounds and dispersion solvents;

[0026] S2. Add quantum dots to the system of boron-containing compound and dispersion solvent and introduce inert gas;

[0027] S3. The system obtained in S2 is heated, mixed and dispersed, and kept at a constant temperature for reaction. During this process, boron-containing compounds react with quantum dots to form tri-coordinate boron-containing quantum dot complexes and tetra-coordinate boron-containing quantum dot complexes. In the tri-coordinate boron-containing quantum dot complex, the boron-containing compound is covalently bonded to the quantum dots, and in the tetra-coordinate boron-containing quantum dot complex, the boron-containing compound is coordinately bonded to the quantum dots. The ratio of XB coordinate bonds in the boron-containing quantum dot dispersion to the sum of the number of XB covalent bonds and XB coordinate bonds is 0.10%-50%, where X is selected from X1, X2, X3, X4, X5, and X6.

[0028] S4, Cooling;

[0029] In S3, the general chemical formula of the three-coordinate boron-containing quantum dot complex is as shown in Formula 1 below, and the general chemical formula of the four-coordinate boron-containing quantum dot complex is as shown in Formula 2 below.

[0030] Where QD stands for quantum dot; R8, R9, R 10 R 11 R 12 R 13 Each of the elements is independently selected from alkoxy, hydrocarbon, substituted hydrocarbon, halogen, carboxyl, hydroxyl, aldehyde, ester, and amide groups. The substituents in the substituted hydrocarbon groups are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups. n1 = a natural number, n2 = a natural number, and X1, X2, X3, X4, X5, and X6 are independently selected from group VIA, group VA, and group IVA elements, respectively.

[0031] In some preferred embodiments of this disclosure, the boron content in the boron-containing quantum dot dispersion is 1000ppm-9000ppm.

[0032] In some preferred embodiments of this disclosure, in S2, the mass ratio of quantum dots to boron-containing compounds is 1:0.25-5, and / or, in S1, the mass ratio of boron-containing compounds to dispersing solvent is 0.01-0.5:1.

[0033] In some preferred embodiments of this disclosure, the dispersing solvent in S1 includes at least one of alkanes, aromatics, organic amines, octadecenes, organic carboxylic acids containing 1-18 carbon atoms, liquid paraffin, acrylates, organosilanes, and organophosphines.

[0034] In some preferred embodiments of this disclosure, the reaction temperature of the heat preservation reaction in S3 is higher than the melting point of the boron-containing compound and the dispersing solvent system, but lower than the boiling point of the boron-containing compound and the dispersing solvent system, the reaction time is 0.1h-3h, and the stirring speed for mixing and dispersing is 100rpm-300rpm.

[0035] In some preferred embodiments of this disclosure, when it is necessary to increase the proportion of covalent bonds, the reaction temperature in S3 is controlled to be 100°C-300°C; when it is necessary to increase the proportion of coordinate bonds, the reaction temperature in S3 is controlled to be 30°C-100°C and not equal to 100°C.

[0036] In some preferred embodiments of this disclosure, the quantum dots have a core-shell structure or a bare core structure, and the quantum dots exist in the form of a solid or a concentrated liquid, wherein the mass fraction of the solid content of quantum dots in the concentrated liquid is 5%-50%.

[0037] In some preferred embodiments of this disclosure, the boron-containing compound includes at least one of the following three general formulas and their dehydration condensation, esterification, and amidation derivatives:

[0038] General formula 1, R1, R2, and R3 are each independently selected from hydrocarbon groups, alkoxy groups, halogens, and substituted hydrocarbon groups;

[0039] General Formula 2 R4 and R5 are each independently selected from carboxyl, substituted hydrocarbon, halogen, hydrocarbon, alkoxy, and hydroxyl groups;

[0040] Formula 3 R6 is selected from H or from substituted hydrocarbon groups, halogens, aldehydes, carboxyl groups, and hydroxyalkyl groups; R7 is selected from hydrocarbon groups, alkoxy groups, hydroxyalkyl groups, and hydroxyl groups.

[0041] In the three general formulas, each substituent in the substituted hydrocarbon group is independently selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups.

[0042] In some preferred embodiments of this disclosure, the boron-containing compound includes at least formula III.

[0043] In some preferred embodiments of this disclosure, the number of carbon atoms in any carbon-containing group of Formula I, Formula II, and Formula III is less than 18, wherein the hydrocarbon group is selected from alkyl, aryl, alkenyl, and alkynyl.

[0044] Thirdly, this disclosure provides a boron-containing quantum dot dispersion, which is prepared by the method for preparing boron-containing quantum dot dispersion described in the second aspect.

[0045] Fourthly, this disclosure provides a method for preparing a boron-containing quantum dot composite plate, comprising the following steps:

[0046] S101 provides boron-containing compounds, quantum dot concentrates, polymer granules, and functional additives for sheet materials;

[0047] S102. Mix the quantum dot concentrate with at least a portion of the polymer particles to obtain a quantum dot polymer mixture;

[0048] S103. A mixture of quantum dot polymers, boron-containing compounds, and functional additives for boards are melt-extruded to form a boron-containing quantum dot composite board. During this process, the boron-containing compounds react with the quantum dots to form tri-coordinate boron-containing quantum dot composites and tetra-coordinate boron-containing quantum dot composites. In the tri-coordinate boron-containing quantum dot composite, the boron-containing compounds are covalently bonded to the quantum dots, and in the tetra-coordinate boron-containing quantum dot composite, the boron-containing compounds are coordinately bonded to the quantum dots. The ratio of XB coordinate bonds in the boron-containing quantum dot composite board to the sum of the number of XB covalent bonds and XB coordinate bonds is 0.10%-50%, where X is selected from X1, X2, X3, X4, X5, and X6.

[0049] In S103, the general chemical formula of the three-coordinate boron-containing quantum dot complex is as shown in Formula 1 below, and the general chemical formula of the four-coordinate boron-containing quantum dot complex is as shown in Formula 2 below.

[0050] Where QD stands for quantum dot; R8, R9, R 10 R 11 R 12 R 13 Each of the elements is independently selected from alkoxy, hydrocarbon, substituted hydrocarbon, halogen, carboxyl, hydroxyl, aldehyde, ester, and amide groups. The substituents in the substituted hydrocarbon groups are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups. n1 = a natural number, n2 = a natural number, and X1, X2, X3, X4, X5, and X6 are independently selected from group VIA, group VA, and group IVA elements, respectively.

[0051] In some preferred embodiments of this disclosure, the boron content in the boron-containing quantum dot composite plate is 13ppm-1750ppm.

[0052] In some preferred embodiments of this disclosure, the mass ratio of quantum dots to the total amount of boron compounds is 1:0.5-40, and the mass of the boron compounds used for coordination bonding with other lone pair electrons or conjugated electron donors in the raw materials other than quantum dots is 1.2%-1000% of the mass of quantum dots.

[0053] In some preferred embodiments of this disclosure, the melt extrusion process of S103 includes: performing a second mixed extrusion of a boron-containing compound, an antioxidant, a light stabilizer, and another portion of polymer granules to obtain auxiliary granules; then feeding the quantum dot polymer mixture and the auxiliary granules into a first extruder, feeding the dispersant and toughening agent into a second extruder and a third extruder respectively, and then performing melt extrusion; wherein, the temperature of the second mixed extrusion is 180℃-220℃.

[0054] In some preferred embodiments of this disclosure, the melt extrusion conditions described in S103 include: a processing temperature of 210°C-270°C and a reaction time of 1-2 min.

[0055] In some preferred embodiments of this disclosure, the stirring speed of the first mixture in S102 is 300-700 rpm.

[0056] In some preferred embodiments of this disclosure, the boron-containing quantum dot composite plate is a boron-containing quantum dot optical diffusion plate, and the corresponding board functional additives include at least one of antioxidants, light diffusing agents, toughening agents, and light stabilizers; the quantum dots include red quantum dots and / or green quantum dots, and the polymer granules are selected from polystyrene, polymethyl methacrylate, polycarbonate, polyethylene, and polypropylene.

[0057] More preferably, the thickness of the boron-containing quantum dot composite plate is 1.2mm-3.0mm.

[0058] More preferably, in S101, based on the total amount of raw materials, the mass fraction of boron-containing compounds is 0.05%-1%, the mass fraction of quantum dot concentrate is 0.05%-0.2%, the mass fraction of quantum dots in the quantum dot concentrate is 5%-50%, the mass fraction of antioxidant is 0.1%-2%, the total mass fraction of light diffusing agent and toughening agent is 0.5%-2%, and the mass fraction of light stabilizer is 0.05%-2%.

[0059] In some preferred embodiments of this disclosure, the boron-containing compound includes at least one of the following three general formulas and their dehydration condensation, esterification, and amidation derivatives:

[0060] General formula 1, R1, R2, and R3 are each independently selected from hydrocarbon groups, alkoxy groups, halogens, and substituted hydrocarbon groups;

[0061] General Formula 2 R4 and R5 are each independently selected from carboxyl, substituted hydrocarbon, halogen, hydrocarbon, alkoxy, and hydroxyl groups;

[0062] Formula 3 R6 is selected from H or from substituted hydrocarbon groups, halogens, aldehydes, carboxyl groups, and hydroxyalkyl groups; R7 is selected from hydrocarbon groups, alkoxy groups, hydroxyalkyl groups, and hydroxyl groups.

[0063] In the three general formulas, each substituent in the substituted hydrocarbon group is independently selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups.

[0064] In some preferred embodiments of this disclosure, the boron-containing compound includes at least formula III.

[0065] In some preferred embodiments of this disclosure, the number of carbon atoms in any carbon-containing group of Formula I, Formula II, and Formula III is less than 18, wherein the hydrocarbon group is selected from alkyl, aryl, alkenyl, and alkynyl.

[0066] Fifthly, this disclosure provides a boron-containing quantum dot composite plate, which is prepared by the method for preparing a boron-containing quantum dot composite plate described in the fourth aspect.

[0067] In a sixth aspect, this disclosure provides an application of the boron-containing quantum dot composite aggregate described in the first aspect in quantum dot diffuser plates, quantum dot phototransfer films, quantum dot on-chip packages, and quantum dot electroluminescent devices. Beneficial effects:

[0068] This disclosure, through the aforementioned technical solution, particularly through boron-containing compound-stabilized quantum dots, forms three-coordinate boron-containing quantum dot complexes and four-coordinate boron-containing quantum dot complexes with suitable boron content. Since boron has more valence orbitals (4) than valence bond electrons (3), when boron forms neutral compounds with quantum dots, it mainly undergoes sp2 hybridization to form planar triangular three-coordinate boron-containing quantum dot complexes while retaining an empty p orbital. This gives the three-coordinate boron compounds a significant electron-deficient property, making them readily accept electron-rich group attacks to form four-coordinate boron-containing quantum dot complexes. Therefore, boron-containing compounds can be used as… A Z-type ligand binds to the anions on the surface of quantum dots to form a more stable protection. The boron compound has good heat resistance and ensures excellent optical performance, effectively avoiding the appearance of black and yellow spots. Furthermore, by controlling the ratio of XB coordination bonds to the sum of XB covalent bonds and XB coordination bonds in the boron-containing quantum dot complex aggregates within an appropriate range, the strong binding ability of the three-coordinate boron-containing quantum dot complex and the strong oxidation resistance of the four-coordinate boron-containing quantum dot complex can be fully utilized. This approach is more conducive to balancing strong binding ability and oxidation resistance, resulting in better heat resistance, stability, and longer lifespan, further effectively preventing the appearance of black and yellow spots.

[0069] Compared to existing quantum dot composites, this disclosure significantly improves the stability of quantum dots. The fundamental principle is that boron-containing compounds (especially electron-deficient three-coordinate boron compounds) can act as ligands to protect the quantum dot anions, forming three-coordinate and four-coordinate boron-containing quantum dot composites with suitable boron content, thereby enhancing the stability of the quantum dots. This disclosure has a wide range of applications. In homogeneous systems, as long as the quantum dot surface is combined with the boron-containing compound provided in this disclosure, the stability improvement effect can be achieved regardless of the application. Furthermore, it can also improve the electron transport and stability performance of quantum dot materials in electroluminescence applications.

[0070] In the preferred embodiment of this disclosure, the mass content of boron element is controlled within a suitable range for boron-containing quantum dot complex aggregates existing in different forms. This is beneficial to improving the stability of quantum dots, enabling the boron-containing compounds to better and longer protect the optical properties of quantum dots, and further effectively avoiding the appearance of black and yellow spots. Attached Figure Description

[0071] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0072] Figure 1 shows the PLQY variation curves after aging for different times on quantum dot PS optical sheets prepared from green quantum dots obtained in some embodiments and comparative examples.

[0073] Figure 2 shows the PLQY variation curves after aging for different times on the quantum dot PS optical sheets prepared from red quantum dots obtained in some embodiments and comparative examples.

[0074] Figure 3 shows the color coordinate x of the boron-containing quantum dot optical diffusion plates obtained in some embodiments and comparative examples as a function of aging time.

[0075] Figure 4 shows the color coordinate y of the boron-containing quantum dot optical diffusion plates obtained in some embodiments and comparative examples as a function of aging time.

[0076] Figure 5 shows the Lv curves of boron-containing quantum dot optical diffusion plates obtained in some embodiments and comparative examples as a function of aging time. Detailed Implementation

[0077] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the ranges, the endpoint values ​​of the ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. The terms "optional" and "discretionary" mean that they may or may not be included (or may or may not be present).

[0078] In a first aspect, this disclosure provides a boron-containing quantum dot composite aggregate comprising a three-coordinate boron-containing quantum dot composite and a four-coordinate boron-containing quantum dot composite formed by chemical bonding of a boron-containing compound to quantum dots. In the three-coordinate boron-containing quantum dot composite, the boron-containing compound is covalently bonded to the quantum dots, and in the four-coordinate boron-containing quantum dot composite, the boron-containing compound is coordinately bonded to the quantum dots. The ratio of XB coordinate bonds to the sum of the number of XB covalent bonds and XB coordinate bonds in the boron-containing quantum dot composite aggregate is 0.10%-50%, where X is selected from X1, X2, X3, X4, X5, and X6. This disclosure employs an appropriate ratio of coordinate and covalent bonds, which can balance the stability of the boron-containing quantum dot composite aggregate while enhancing the protection of anions on the quantum dot surface (wherein the three-coordinate covalent bonds are stronger and the four-coordinate coordination bonds are more resistant to oxidation), thereby improving the stability and lifespan of the quantum dot composite material.

[0079] In this disclosure, the number of coordinate and covalent bonds can be determined by molecular absorption spectroscopy. The positions of the characteristic peaks in the molecular spectrum (including BS covalent and BS coordinate bonds) can be found in chemical handbooks and will not be elaborated here. For example, in molecular absorption spectra, such as the BO bond, the vibrational frequency in the Raman spectrum is 700-900 cm⁻¹. -1 The BO bond shows a peak position of 1350–1310 cm⁻¹ in NMR and IR spectra. -1 The coordination number can also be determined directly by the chemical shifts of boron atoms using nuclear magnetic resonance boron spectroscopy. Regardless of the method used to detect the number of coordinate and covalent bonds, they all fall within the range of coordinate and covalent bond ratios disclosed herein.

[0080] In this disclosure, the proportion of XB coordinate bonds to the sum of XB covalent bonds and XB coordinate bonds is 0.10%-50%, for example, the corresponding proportions can be 0.10%, 0.5%, 0.8%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%. The percentages are 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, etc., and the range between any two point values. More preferably, for example, it can be 8%-30%.

[0081] The general chemical formula of the tricoordinate boron-containing quantum dot complex is shown in Formula 1 below, and the general chemical formula of the tetracoordinate boron-containing quantum dot complex is shown in Formula 2 below.

[0082] Where QD stands for quantum dot; R8, R9, R 10 R 11 R 12 R 13 Each of the elements is independently selected from alkoxy, hydrocarbon, substituted hydrocarbon, halogen, carboxyl, hydroxyl, aldehyde, ester, and amide groups. The substituents in the substituted hydrocarbon groups are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups. n1 = a natural number, n2 = a natural number, and X1, X2, X3, X4, X5, and X6 are independently selected from group VIA, group VA, and group IVA elements, respectively.

[0083] In this disclosure, "hydrocarbon group" includes alkyl, aryl, alkenyl, and alkynyl. "Substituted hydrocarbon group" refers to a group in which a hydrogen atom selected from alkyl, aryl, alkenyl, and alkynyl is substituted with a substituent. For example, a hydrocarbon group having 1-18 carbon atoms is selected from alkyl having 1-18 carbon atoms, aryl having 6-18 carbon atoms, alkenyl having 2-18 carbon atoms, and alkynyl having 2-18 carbon atoms; a substituted hydrocarbon group having 1-18 carbon atoms is selected from substituted alkyl having 1-18 carbon atoms, substituted aryl having 6-18 carbon atoms, substituted alkenyl having 2-18 carbon atoms, and substituted alkynyl having 2-18 carbon atoms. In this disclosure, "1-18 carbon atoms" means that the number of carbon atoms can be selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, and 18. "The number of carbon atoms is 6-18" means that the number of carbon atoms can be selected from 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, and 18, and so on.

[0084] The quantum dots (QDs) disclosed herein can be specifically monodisperse quantum dot particles or quantum dot aggregates. As long as the surface of the quantum dots contains at least one element from Group VIA, Group VA, or Group IVA, they can form tricoordinate boron-containing quantum dot complexes and / or tetracoordinate boron-containing quantum dot complexes. It is understood that X1, X2, X3, X4, X5, and X6 are elements present on the surface of the quantum dot QD, enabling the quantum dots to chemically bond with boron-containing compounds.

[0085] Among them, n1 and n2 are natural numbers, for example, each can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, etc. The measured values ​​of n1 and n2 in the boron-containing quantum dot complex aggregates and the n1 and n2 calculated based on the theoretical values ​​of the raw material input are both natural numbers.

[0086] Preferably, n1 = 0-20 and n2 = 0-20. Using suitable and preferred ranges for n1 and n2 can ensure the solution properties of boron-containing quantum dot complex aggregates while enhancing the binding force between boron-containing compound molecules and the quantum dot surface (more covalent or coordination binding sites), thereby further improving the dispersibility and stability of boron-containing quantum dot complex aggregates.

[0087] In some preferred embodiments of this disclosure, X1, X2, X3, X4, X5, and X6 are each independently selected from O, S, Se, Te, N, P, As, C, Si, and Ge.

[0088] In some preferred embodiments of this disclosure, R8, R9, R 10 R 11 R 12 R 13 Each group is independently selected from alkoxy groups, hydrocarbon groups, substituted hydrocarbon groups, halogens, carboxyl groups, hydroxyl groups, aldehyde groups, ester groups, and amide groups, each with 1-18 carbon atoms. The hydrocarbon group can be a straight-chain hydrocarbon group, a branched hydrocarbon group, or a cyclic hydrocarbon group. As long as it meets the above-mentioned range and the corresponding general formula structure and the corresponding content of coordinate and covalent bonds, the effects of this disclosure can be achieved.

[0089] More preferably, R8, R9, R 10 R 11 R 12 R 13 Each of the following is independently selected from alkoxy groups having 1-18 carbon atoms, alkyl groups having 1-18 carbon atoms, preferably 2-16 carbon atoms, aryl or substituted aryl groups having 6-18 carbon atoms, and hydroxyl groups.

[0090] More preferably, the substituent group in the substituted aryl group having 6-18 carbon atoms is selected from at least one of alkyl, halogen, hydroxyalkyl, alkoxy, halogen, carboxyl, and aldehyde groups.

[0091] The halogen disclosed herein can be selected from fluorine, chlorine, and bromine.

[0092] In some preferred embodiments, the boron-containing quantum dot composite aggregate is a boron-containing quantum dot composite plate, wherein R8, R9, and R... 10 R 11 R 12 R 13 All halogens contained are fluorine. The preferred embodiment of this disclosure not only ensures improved quantum dot stability and excellent optical performance, but also effectively prevents the formation of black and yellow spots.

[0093] In some preferred embodiments of this disclosure, the boron-containing quantum dot composite aggregate is a boron-containing quantum dot dispersion, wherein R8, R9, and R... 10 R 11 They do not both contain phenyl groups; and / or, R8 and R9 are not both halogens, and R 10 R 11 The preferred scheme disclosed herein is not simultaneously halogenated. It is more conducive to improving the stability of quantum dots, while ensuring excellent optical performance, and further effectively avoiding the appearance of black and yellow spots.

[0094] This disclosure does not impose any restrictions on the form in which boron-containing quantum dot complex aggregates exist, and the form can be selected according to the actual application.

[0095] In some preferred embodiments of this disclosure, the boron-containing quantum dot composite aggregate is a boron-containing quantum dot dispersion. The boron content in the boron-containing quantum dot dispersion is 1000ppm-9000ppm, specifically 1000ppm, 1500ppm, 2000ppm, 2500ppm, 3000ppm, 3500ppm, 4000ppm, 4500ppm, 5000ppm, 5500ppm, 6000ppm, 6500ppm, 7000ppm, 7500ppm, 8000ppm, 8500ppm, 9000ppm, etc., or any range between two values. Using this preferred boron content results in better stability of the boron-containing quantum dot dispersion and a stronger protective effect of the boron compound on the optical properties of the quantum dots.

[0096] In some preferred embodiments of this disclosure, the boron-containing quantum dot composite aggregate is a boron-containing quantum dot composite plate, wherein the boron content in the boron-containing quantum dot composite plate is 13ppm-1750ppm, specifically, it can be 13ppm, 20ppm, 30ppm, 40ppm, 50ppm, 60ppm, 70ppm, 80ppm, 90ppm, 100ppm, 200ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm, 800ppm, 900ppm, 1000ppm, 1100ppm, 1200ppm, 1300ppm, 1400ppm, 1500ppm, 1600ppm, 1700ppm, 1750ppm, etc., or any range between two values. With this preferred suitable boron content, the stability of the boron-containing quantum dot composite plate gradually improves, and the protective effect of the boron-containing compound on the optical properties of the quantum dots is stronger.

[0097] The boron-containing quantum dot composite plate disclosed herein can be prepared by conventional methods using a corresponding quantum dot dispersion as a raw material, or it can be prepared directly using a corresponding boron-containing compound as a raw material. In this disclosure, compared to the boron-containing quantum dot composite plate, the boron-containing quantum dot dispersion has a higher quantum dot content, allowing for a higher boron content to facilitate improved processing and handling efficiency.

[0098] In this disclosure, a three-coordinate boron-containing compound is formed by covalently bonding anions (such as group V and VI elements such as sulfur, selenium, oxygen, nitrogen, and phosphorus) on the surface of quantum dots to form a three-coordinate boron-containing quantum dot complex. Here, ZnS is used as an example on the quantum dot surface, and the bonding process is as follows:

[0099] Compared to traditional Z-type ligands, the anion adjacent to boron in the three-coordinate boron-containing quantum dot complex disclosed in this paper exhibits stronger antioxidant capacity. This is due to the conjugation effect between the empty p orbitals of the three-coordinate boron and the lone pair electrons of the adjacent anion. Under the influence of this conjugation effect, the electrons of the anion are more difficult to be taken away by oxidants. The three-coordinate boron-containing quantum dot complex directly binds the lone pair electrons of the anion on the quantum dot surface (such as sulfur) through coordination bonds to form a four-coordinate boron-containing quantum dot complex. This significantly reduces the reducing power of the anion, making it more difficult to be oxidized (the effect of coordination bonds makes it more difficult for the anion to be taken away by oxidants; this effect is stronger than the conjugation effect).

[0100] In some preferred embodiments of this disclosure, the tricoordinated boron-containing quantum dot complex is selected from: At least one of them.

[0101] The four-coordinate boron-containing quantum dot complex was selected from: At least one of them.

[0102] In some preferred embodiments of this disclosure, the quantum dot has a bare core structure, and the surface of the bare core structure has at least one of group IVA atoms, group VA anions, and group VIA anions.

[0103] In some other preferred embodiments of this disclosure, the quantum dot has a core-shell structure, and the shell surface of the core-shell structure contains at least one of group IVA atoms, group VA anions, and group VIA anions.

[0104] Any quantum dot whose surface has at least one of group IVA atoms, group VA anions, or group VIA anions can be used in this disclosure and can be chemically bonded to boron-containing compounds to form boron-containing quantum dot complex aggregates including tricoordinate boron-containing quantum dot complexes and tetracoordinate boron-containing quantum dot complexes.

[0105] The quantum dot surface contains group VA and group VIA anions, such as anions corresponding to group VA and group VIA elements like sulfur, selenium, oxygen, nitrogen, and phosphorus.

[0106] In some specific embodiments of this disclosure, the bare-core quantum dots can be binary quantum dots (such as CdSe, CdS, ZnSe, ZnS quantum dots), M-ary alloy quantum dots (M is a positive integer ≥3; ternary, quaternary, pentary, and even higher-order elements belong to alloy quantum dots, which are obtained by mixing and alloying multiple binary components), etc. Exemplarily, bare-core quantum dots can be selected from IA-IVA-VIIA group compound semiconductors (such as CsPdCl3), IIIA-VA group compound semiconductors (such as InP), IVA-VIA group compound semiconductors (such as PdS), IVA-VIA-VIA group compound semiconductors (such as PdSeS), IIA-IIIA-VA group compound semiconductors, IIIA-VA-VIA group compound semiconductors (such as InPS), IIA-IIIA-VA-VIA group compound semiconductors, IIA-VIA group compound semiconductors, IIA-IIA-VI ... Compound semiconductors of Groups A-VIA, IA-IIIA-IVA-VIA-VIIA, IB-IIIA-VIA (e.g., CuInS), IB-IIIA-VIA-VIA (e.g., CuInSeS), IIB-VIA (e.g., CdSe), IIIA-IIB-VA (e.g., InZnP), IIB-IIIA-VIA, IIB-IIIA-VA-VIA, IB-IIIA-VIA, IB-IIB-IIIA-VIA, IIB-IIB-VIA (e.g., ZnCdSe), IIB-IIB-VIA-VIA (e.g., ZnCdSeS), IIB-VIA-VIA (e.g., CdSeS), IB-IIB-IVA-VIA, perovskite quantum dots, and carbon quantum dots.

[0107] In some specific embodiments of this disclosure, the feasible range of core materials for core-shell structured quantum dots is consistent with that for bare core structured quantum dots, and the shell material can be selected from inorganic compounds (such as inorganic oxides, sulfides, nitrides), organic polymer compounds (such as polyamides, polystyrene, etc.), organosilicon polymers (such as polytetramethoxysilane, polyphenyltrimethoxysilane, etc.).

[0108] Furthermore, the shell material of core-shell quantum dots can also include group IIB-VIA compounds (such as ZnS, ZnO, etc.), group IIA-VIA compounds (such as MgO), group IIIA-VA compounds (such as BN), group IIIA-VIA compounds (such as Al2O3, B2O3, etc.), group IIIA-VIA compounds (such as Al2O3, B2O3, etc.), group IVA-VIA compounds (such as SiO2), group IVB-VIA compounds (such as ZrO2), and group VIIA halide metal salt compounds (such as ZnCl2).

[0109] In the aforementioned corresponding compound semiconductors, elements from different groups can be combined arbitrarily, and one or more elements from the same group can be combined arbitrarily; for example, IIB-VIA compound semiconductors can be a combination of one or more elements from the IIB group and one or more elements from the VIA group, and this combination can be a bare core structure or a core-shell structure.

[0110] For example, quantum dots corresponding to group IIB-VIA compound semiconductors can include binary core-shell structures (such as CdSe / CdS, CdSe / ZnS, CdSe / CdS / ZnS, CdTe / ZnS, CdS / ZnS, etc.), ternary core-shell structures (such as CdSeS / ZnS, ZnCdSe / ZnS, CdSeTe / ZnS, etc.), and quaternary core-shell structures (such as ZnCdSeS / ZnS, ZnCdSeTe / ZnS, etc.). It is understood that CdSe / CdS refers to a core-shell structure with CdSe as the core and CdS as the shell, ZnCdSe / ZnS refers to a core-shell structure with ZnCdSe as the core and ZnS as the shell, and so on.

[0111] For example, quantum dots corresponding to IIB-IIIA-VIA group compound semiconductors may include CuInSe2, CuInS2, CuInSe2 / ZnS, and CuInS2 / ZnS, etc.

[0112] For example, quantum dots corresponding to IVA-VIA family compound semiconductors may include: SnS, SnSe, SnTe, PbS, PbSe, PbTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbSSe, SnPbSeTe, SnPbSTe, etc.

[0113] For example, quantum dots corresponding to IB-IIB-IVA-VIA group compound semiconductors may include CuZnSnSe, CuZnSnS, etc.

[0114] For example, quantum dots corresponding to IIIA-VA group compound semiconductors may include: GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, InP / ZnS, InP / ZnSe / ZnS, etc.

[0115] The boron-containing quantum dot complex aggregates disclosed herein can exist in any form, such as in solution or in plate form.

[0116] In this disclosure, the structures of tri-coordinated and tetra-coordinated boron-containing quantum dot complexes present in boron-containing quantum dot complex aggregates can be determined by nuclear magnetic resonance. 11 The absorption spectra used for testing include B-spectrum, synchrotron radiation absorption testing, and covalent bond infrared characteristic absorption spectrum. These testing methods are all existing technologies and will not be described in detail here.

[0117] Secondly, this disclosure provides a method for preparing a boron-containing quantum dot dispersion, comprising the following steps:

[0118] S1. Prepare boron-containing compounds and dispersion solvents;

[0119] S2. Add quantum dots to the system of boron-containing compound and dispersion solvent and introduce inert gas;

[0120] S3. The system obtained in S2 is heated, mixed and dispersed, and kept at a constant temperature for reaction. During this process, boron-containing compounds react with quantum dots to form tri-coordinate boron-containing quantum dot complexes and tetra-coordinate boron-containing quantum dot complexes. In the tri-coordinate boron-containing quantum dot complex, the boron-containing compound is covalently bonded to the quantum dots, and in the tetra-coordinate boron-containing quantum dot complex, the boron-containing compound is coordinately bonded to the quantum dots. The ratio of XB coordinate bonds in the boron-containing quantum dot dispersion to the sum of the number of XB covalent bonds and XB coordinate bonds is 0.10%-50%, where X is selected from X1, X2, X3, X4, X5, and X6.

[0121] S4, Cooling;

[0122] In S3, the general chemical formula of the three-coordinate boron-containing quantum dot complex is as shown in Formula 1 below, and the general chemical formula of the four-coordinate boron-containing quantum dot complex is as shown in Formula 2 below.

[0123] Where QD stands for quantum dot; R8, R9, R 10 R 11 R 12 R 13Each of the elements is independently selected from alkoxy, hydrocarbon, substituted hydrocarbon, halogen, carboxyl, hydroxyl, aldehyde, ester, and amide groups. The substituents in the substituted hydrocarbon groups are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups. n1 = a natural number, n2 = a natural number, and X1, X2, X3, X4, X5, and X6 are independently selected from group VIA, group VA, and group IVA elements, respectively.

[0124] Preferably, the boron content in the boron-containing quantum dot dispersion is 1000ppm-9000ppm.

[0125] In some preferred embodiments of the second aspect of this disclosure, in step S2, the mass ratio of quantum dots to boron-containing compounds is 1:0.25-5. This preferred approach enhances the direct covalent bonding between quantum dots and boron-containing compounds, thereby facilitating an increase in the proportion of tricoordinate boron-containing quantum dot complexes.

[0126] In some preferred embodiments of the second aspect of this disclosure, the mass ratio of the boron-containing compound to the dispersing solvent in S1 is 0.01-0.5:1. This preferred approach promotes the dispersion of the boron-containing compound while enhancing the coupling effect between them (with larger values ​​for the natural numbers n1 and n2), thereby improving the structural stability of the tri-coordinate and tetra-coordinate boron-containing quantum dot complexes (superior to having more and stronger binding sites between BX).

[0127] In some preferred embodiments of the second aspect of this disclosure, the dispersing solvent in S1 includes at least one selected from alkanes, aromatics, organic amines, octadecenes, organic carboxylic acids containing 1-18 carbon atoms, liquid paraffin, acrylates, organosilanes, and organophosphorus compounds. Organic carboxylic acids containing 1-18 carbon atoms may be selected, for example, from octanoic acid, oleic acid, linoleic acid, stearic acid, etc.

[0128] In some preferred embodiments of the second aspect of this disclosure, the reaction temperature of the heat-preserving reaction in S3 is higher than the melting point of the system of boron-containing compound and dispersing solvent, but lower than the boiling point of the system of boron-containing compound and dispersing solvent, and the reaction time is 0.1 h to 3 h. This preferred method allows the solvent to remain in a liquid state while avoiding excessive solvent evaporation due to high reaction temperature, thereby facilitating a greater degree of reaction.

[0129] Preferably, the stirring speed for mixing and dispersing is 100 rpm to 300 rpm. This preferred method can avoid material splashing and sticking to the walls, thereby improving the uniformity of the reaction.

[0130] The reaction temperature of the heat preservation reaction in S3 described in this disclosure can be determined according to the ratio of covalent bonds and coordinate bonds to be formed. For example, it can be a high temperature range of 100℃-300℃, preferably 100℃-230℃, which is conducive to the formation of covalent bonds, or a low temperature range of 30℃-100℃, which is conducive to the formation of coordinate bonds, but not equal to 100℃.

[0131] In some preferred embodiments of the second aspect of this disclosure, when it is necessary to increase the proportion of covalent bonds, the reaction temperature in S3 is controlled to be 100℃-300℃, preferably 100℃-230℃; when it is necessary to increase the proportion of coordinate bonds, the reaction temperature in S3 is controlled to be 30℃-100℃, but not equal to 100℃. Using this preferred approach, the proportion of covalent and coordinate bonds can be controlled more quickly and accurately.

[0132] In some preferred embodiments of the second aspect of this disclosure, the quantum dots have a core-shell structure or a bare core structure, and exist in solid or concentrated form, with the mass fraction of quantum dots in the concentrated solution being 5%-50%. This preferred approach ensures homogeneity of the system solution while maximizing the concentration of reactants (quantum dots), thereby improving the processing efficiency of boron-containing quantum dot dispersions.

[0133] In schemes where quantum dots exist in the form of a concentrated solution, the solvent in the concentrated solution can be at least one of the following: alkanes (such as hexane, octane, liquid paraffin, octadecene, etc.), aromatics (such as toluene), organic amines (such as trioctylamine), organic carboxylic acids containing 1 to 18 carbon atoms (such as oleic acid), organic lipids (such as acrylates), organosilanes (such as mercaptopropyltrimethoxysilane), and organophosphorus compounds (such as trioctylphosphine). Those skilled in the art can select the solvent in the concentrated solution according to actual needs.

[0134] In some preferred embodiments of the second aspect of this disclosure, the boron-containing compound includes at least one of the following three general formulas and their dehydration condensation, esterification, and amidation derivatives:

[0135] General formula 1, R1, R2, and R3 are each independently selected from hydrocarbon groups, alkoxy groups, halogens, and substituted hydrocarbon groups;

[0136] General Formula 2 R4 and R5 are each independently selected from carboxyl, substituted hydrocarbon, halogen, hydrocarbon, alkoxy, and hydroxyl groups;

[0137] Formula 3 R6 is selected from H or from substituted hydrocarbon groups, halogens, aldehydes, carboxyl groups, and hydroxyalkyl groups; R7 is selected from hydrocarbon groups, alkoxy groups, hydroxyalkyl groups, and hydroxyl groups. In the three general formulas, each substituent in the substituted hydrocarbon group is independently selected from at least one of halogens, hydroxyalkyl groups, alkyl groups, hydroxyl groups, alkoxy groups, carboxyl groups, aldehyde groups, ester groups, and amide groups. The hydrocarbon group can be a straight-chain hydrocarbon group, a branched hydrocarbon group, or a cyclic hydrocarbon group. As long as it conforms to the above range and the corresponding general formula structure and the mass content of the corresponding coordinated boron-containing quantum dot complex, the effects of this disclosure can be achieved.

[0138] It is understood that boron-containing compounds may conform to one or more of the three general formulas mentioned above. For example, they may include at least one compound of general formula one, at least one compound of general formula two, and at least one compound of general formula three.

[0139] Understandably, the hydrocarbon group is selected from alkyl, aryl, alkenyl, and alkynyl groups.

[0140] In some preferred embodiments of this disclosure, the boron-containing compound includes at least Formula III, which is more conducive to improving its dispersibility in polymer substrates (such as polystyrene (PS)) while enhancing the electron-withdrawing effect of boron through an inductive effect, thereby improving its protection against anions.

[0141] In some preferred embodiments of the second aspect of this disclosure, the number of carbon atoms in any carbon-containing group of Formula 1, Formula 2, or Formula 3 is 18 or less.

[0142] More preferably, in formula II, R4 is selected from carboxyl, substituted hydrocarbon, allyl, aryl, and hydroxyl groups, and R5 is selected from alkoxy, hydroxyl, hydroxyalkyl, and hydrocarbon groups.

[0143] R6 can be selected from one or more of the aforementioned ranges, and different groups of R6 can be distributed at different positions on the benzene ring in Formula 3. In some more preferred embodiments of the second aspect of this disclosure, in Formula 3, the group position of R6 is meta-m or para-p, which is more conducive to the electron-withdrawing group enhancing the electron-capturing ability of the empty orbitals of boron atoms, and further improving the antioxidant effect of the four-coordinate boron quantum dot complex bound by coordinate bonds.

[0144] In some specific embodiments of this disclosure, the boron-containing compound is selected from the following compounds: wait.

[0145] In the second aspect, using a preferred range of boron-containing compounds is more conducive to the dissolution and dispersion of boron-containing compounds in high-concentration quantum dot solutions and increases their covalent bonding ability with the quantum dot surface.

[0146] In the preparation method of the second aspect of this disclosure, the ratio of coordination bonds and covalent bonds can be controlled by adjusting the time, temperature and other conditions of the heat treatment of the boron-containing compound.

[0147] Thirdly, this disclosure provides a boron-containing quantum dot dispersion, which is prepared by the method for preparing boron-containing quantum dot dispersion described in the second aspect.

[0148] Fourthly, this disclosure provides a method for preparing a boron-containing quantum dot composite plate, comprising the following steps:

[0149] S101 provides boron-containing compounds, quantum dot concentrates, polymer granules, and functional additives for sheet materials;

[0150] S102. Mix the quantum dot concentrate with at least a portion of the polymer particles to obtain a quantum dot polymer mixture;

[0151] S103. A mixture of quantum dot polymers, boron-containing compounds, and functional additives for boards are melt-extruded to form a boron-containing quantum dot composite board. During this process, the boron-containing compounds react with the quantum dots to form tri-coordinate boron-containing quantum dot composites and tetra-coordinate boron-containing quantum dot composites. In the tri-coordinate boron-containing quantum dot composite, the boron-containing compounds are covalently bonded to the quantum dots, and in the tetra-coordinate boron-containing quantum dot composite, the boron-containing compounds are coordinately bonded to the quantum dots. The ratio of XB coordinate bonds in the boron-containing quantum dot composite board to the sum of the number of XB covalent bonds and XB coordinate bonds is 0.10%-50%, where X is selected from X1, X2, X3, X4, X5, and X6.

[0152] In S103, the general chemical formula of the three-coordinate boron-containing quantum dot complex is as shown in Formula 1 below, and the general chemical formula of the four-coordinate boron-containing quantum dot complex is as shown in Formula 2 below.

[0153] Where QD stands for quantum dot; R8, R9, R 10 R 11 R 12 R 13 Each of the following groups is independently selected from alkoxy, hydrocarbon, substituted hydrocarbon, halogen, carboxyl, hydroxyl, aldehyde, ester, and amide groups. The substituents in the substituted hydrocarbon groups are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, and amide groups. n1 = a natural number, n2 = a natural number, and X1, X2, X3, X4, X5, and X6 are independently selected from group VIA, group VA, and group IVA elements, respectively.

[0154] Preferably, the boron content in the boron-containing quantum dot composite plate is 13ppm-1750ppm.

[0155] In some preferred embodiments of the fourth aspect of this disclosure, the mass ratio of the total amount of quantum dots to the total amount of boron-containing compounds is 1:(0.5-40).

[0156] More preferably, the mass of the boron-containing compound used for coordination bonding with other lone pair electrons or conjugated electron donors in the raw material (excluding quantum dots) is 1.2%-1000% of the mass of the quantum dots. This preferred embodiment allows for bonding with Lewis bases (electron donors) other than quantum dots while protecting the anions on the quantum dot surface, thus facilitating the improvement of the thermal conductivity and oxidation resistance of the substrate through the boron-containing composite.

[0157] Among them, it is used to react with other lone pairs of electrons or conjugated electron donors in the raw materials other than quantum dots, such as antioxidants, light stabilizers, group V and VI elements on hindered amines, as well as benzene rings, alkenes, alkynes, etc.

[0158] In some preferred embodiments of the fourth aspect of this disclosure, the melt extrusion conditions described in S103 include: a processing temperature of 210°C-270°C and a reaction time of 1-2 min.

[0159] In some preferred embodiments of the fourth aspect of this disclosure, the stirring speed of the first mixture in S102 is 300-700 rpm.

[0160] The boron-containing quantum dot composite plate disclosed herein can be used in various quantum dot application fields. The corresponding functional additives and polymer granules can be selected according to different application fields. In some preferred embodiments of the fourth aspect of this disclosure, the boron-containing quantum dot composite plate is a boron-containing quantum dot optical diffusion plate, and the corresponding functional additives include at least one of antioxidants, light diffusing agents, toughening agents, and light stabilizers. The raw materials other than boron compounds and quantum dots are common additives in conventional diffusion plates. To ensure balanced product performance, the dosage of each common additive can be determined within the corresponding ranges in the prior art.

[0161] Further preferably, the melt extrusion process of S103 includes: secondly mixing and extruding a boron-containing compound, an antioxidant, a light stabilizer, and another portion of polymer granules to obtain auxiliary granules; then feeding the quantum dot polymer mixture and auxiliary granules into a first extruder, and feeding the dispersant and toughening agent into a second extruder and a third extruder respectively, followed by melt extrusion. Even more preferably, the temperature of the second mixing and extrusion is 180℃-220℃.

[0162] More preferably, in S101, based on the total amount of raw materials, the mass fraction of boron compound is 0.05%-1%, the mass fraction of quantum dot concentrate is 0.05%-0.2%, the mass fraction of quantum dots in the quantum dot concentrate is 5%-50%, the mass fraction of antioxidant is 0.1%-2%, the total mass fraction of light diffusing agent and toughening agent is 0.5%-2%, and the mass fraction of light stabilizer is 0.05%-2%. Adopting this preferred scheme is more conducive to the balanced performance of the produced quantum dot diffuser plate, meeting the requirements of production line processing and product lifespan.

[0163] Preferably, the quantum dots comprise red quantum dots and / or green quantum dots.

[0164] Preferably, the polymer granules are selected from polystyrene, polymethyl methacrylate, polycarbonate, polyethylene, and polypropylene.

[0165] Preferably, the thickness of the boron-containing quantum dot composite board is 1.2mm-3.0mm. A thinner boron-containing quantum dot composite board is more conducive to providing certain mechanical strength and optical path while reducing the amount of substrate used in the board, thus lowering raw material costs.

[0166] The range of boron-containing compounds in the fourth aspect of this disclosure is the same as that in the second aspect, and will not be repeated here.

[0167] The selection of the boron-containing compound in the methods of the second and fourth aspects of this disclosure can be based on whether it facilitates chemical bonding. Preferably, in the preparation of the dispersion of the second aspect of this disclosure, since the mass fraction of quantum dots is relatively high (e.g., 10%), the selected boron-containing compound only needs to have high solubility in the system to match the high concentration of quantum dots and facilitate chemical bonding; further preferred are boron-containing compounds with hydroxyl and / or alkoxy groups, which can utilize the hydrolysis of alkoxy groups and the binding ability of hydroxyl groups to further form a more robust three-coordinate structure with the surface of quantum dots.

[0168] In the preparation of the composite plate according to the fourth aspect of this disclosure, the quantum dot mass fraction is relatively low (e.g., 0.1%), and the range of composite plate substrates such as PS, PMMA, and PC is relatively fixed. Therefore, the boron-containing compound should be more compatible with the chemical environment of the diffusion plate. For example, boron-containing compounds containing alkyl or aryl groups are preferred in polystyrene substrates to facilitate chemical bonding. Further preferred are boron-containing compounds with alkyl and / or aryl groups, which can utilize the hydrophobicity of alkyl and / or aryl groups to improve dispersibility in the PS substrate and form a more oxidation-resistant four-coordinate structure with the quantum dot surface.

[0169] In the preparation of the composite plate according to the fourth aspect of this disclosure, the ratio of coordination bonds and covalent bonds can be controlled by adjusting conditions such as the temperature of the second mixing extrusion, the extrusion temperature of the melt extrusion, the extrusion speed, and the extrusion time.

[0170] Fifthly, this disclosure provides a boron-containing quantum dot composite plate, which is prepared by the method for preparing a boron-containing quantum dot composite plate described in the fourth aspect.

[0171] Compared to the conventional method of directly preparing quantum dot PS optical sheets using quantum dot concentrate, this disclosure adopts a method of directly preparing boron quantum dot composite plates using boron-containing compounds, resulting in boron-containing quantum dot composite plates with better stability and product aging performance.

[0172] In a sixth aspect, this disclosure provides an application of the boron-containing quantum dot composite aggregate described in the first aspect in quantum dot diffuser plates, quantum dot phototransfer films, quantum dot on-chip packages, and quantum dot electroluminescent devices.

[0173] The embodiments of this disclosure described below are exemplary and are only used to explain this disclosure, and should not be construed as limiting this disclosure.

[0174] 1. Preparation of boron-containing quantum dot dispersion:

[0175] Example 1

[0176] Take 200g of decane, 10g of dodecylboronic acid, 2g of 4-methylphenylboronic acid, and 2g of oleic acid and place them in a 500mL four-necked stirred reactor equipped with a reflux condenser. Introduce argon gas and start stirring (100rpm). Add 20g of CdSe / CdS / ZnS core-shell red quantum dot solid (Em (emission wavelength) = 625nm, Fwhm (full width at half maximum) = 23nm) to the system. After the quantum dot solid disperses, heat the system to 160℃ (reaction temperature) and keep it at that temperature for 2h. Then cool it down to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0177] Example 2

[0178] Take 200g of tri-n-octylamine, 10g of boric acid, and 20g of oleic acid and place them in a 500mL four-necked stirred reactor equipped with a reflux condenser. Introduce argon gas and start stirring (200rpm). Add 20g of CdSe / CdS / ZnS core-shell red quantum dot solid (Em=625nm, Fwhm=23nm) to the system. After the quantum dot solid disperses, heat the system to 220℃ and keep it at that temperature for 2h. Then cool it down to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0179] Example 3

[0180] Take 200g of octane, 10g of trioctyl borate, 1g of boric acid, and 2g of oleic acid and place them in a 500mL four-necked stirred reactor equipped with a reflux condenser. Introduce argon gas and start stirring (100rpm). Add 20g of CdSe / CdS / ZnS core-shell green quantum dot solid (Em=538nm, Fwhm=23nm) to the system. After the quantum dot solid disperses, heat the system to 100℃ and keep it at that temperature for 2h. Then cool it down to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0181] In particular, an appropriate amount of oleic acid can increase the polarity of the mixed solvent formed by octane and oleic acid, thus promoting dissolution; at the same time, it can also act as a surface ligand to disperse solid quantum dots to a certain extent.

[0182] Example 4

[0183] Take 200g of liquid paraffin, 10g of difluorophenylboronic acid, 2g of trioctyl borate, and 2g of oleic acid and place them in a 500mL four-necked stirred reactor equipped with a reflux condenser. Introduce argon gas and start stirring (100rpm). Add 20g of CdSe / CdS / ZnS core-shell green quantum dot solid (Em=538nm, Fwhm=23nm) to the system. After the quantum dot solid disperses, heat the system to 230℃ and keep it at that temperature for 2h. Then cool it down to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0184] Example 5

[0185] Take 100g of trimethoxyphenylsilane, 100g of trimethoxydodecylsilane, 10g of hydroxymethylphenylboronic acid, and 2g of oleic acid and place them in a 500mL four-necked stirred reactor equipped with a reflux condenser. Introduce argon gas and start stirring (100rpm). Add 20g of CdSe / CdS / ZnS core-shell green quantum dot solid (Em=538nm, Fwhm=23nm) to the system. After the quantum dot solid disperses, heat the system to 180℃ and keep it at that temperature for 1h. Then cool it down to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0186] Example 6

[0187] Take 200g of trioctylphosphine, 10g of trioctyl borate, and 2g of boric acid and place them in a 500mL four-necked stirred reactor equipped with a reflux condenser. Introduce argon gas and start stirring (100rpm). Add 20g of CdSe / CdS / ZnS core-shell green quantum dot solid (Em=538nm, Fwhm=23nm) to the system. After the quantum dot solid disperses, heat the system to 200℃ and keep it at that temperature for 2h. Then cool it down to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0188] Example 7

[0189] Take 200g of octane, 10g of boric acid, and 2g of diisooctylphosphonic acid and place them in a 500mL four-necked stirred reactor equipped with a reflux condenser. Introduce argon gas and start stirring (100rpm). Add 20g of CdSe / CdS / ZnS core-shell red quantum dot solid (Em=625nm, Fwhm=23nm) to the system. After the quantum dot solid disperses, heat the system to 110℃ and keep it at that temperature for 2h. Then cool it down to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0190] Example 8

[0191] 200g toluene, 10g tributylboron, and 2g 4-methylphenylboronic acid were placed in a 500mL four-necked stirred reactor equipped with a reflux condenser. Argon gas was introduced and stirring was started (100rpm). 20g of CdSe / CdS / ZnS core-shell green quantum dot solids (Em=538nm, Fwhm=23nm) were added to the system. After the quantum dot solids were dispersed, the system was heated to 200℃ and kept at that temperature for 2h. Then the temperature was cooled to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0192] Example 9

[0193] 200g of isobornyl methacrylate, 10g of dimethoxyphenylboronic acid, and 2g of oleic acid were placed in a 500mL four-necked stirred reactor equipped with a reflux condenser. Argon gas was introduced and stirring was started (100rpm). 20g of CdSe / CdS / ZnS core-shell red quantum dot solid (Em=625nm, Fwhm=23nm) was added to the system. After the quantum dot solid dispersed, the system was heated to 180℃ and kept at that temperature for 2h. Then, the temperature was cooled to 30℃ to obtain a uniform boron-containing quantum dot dispersion.

[0194] Example 1-a

[0195] The reaction was carried out in accordance with Example 1, except that the reaction temperature after the quantum dot solid dispersion was increased until the proportion of BX covalent bonds and BX coordination bonds reached the ratio shown in Table 2, and the reaction temperature was below 300°C.

[0196] Example 1-b

[0197] The reaction was carried out in accordance with Example 1, except that the reaction temperature after the quantum dot solid dispersion was reduced until the proportion of BX covalent bonds and BX coordination bonds reached the ratio shown in Table 2, and the reaction temperature was 30℃-100℃ and less than 100℃.

[0198] Example 1-c

[0199] The procedure was carried out in accordance with Example 1, except that the type of quantum dots was different, specifically replaced with core-shell structured CdZnSe / ZnSe / ZnS quantum dots, while the amount remained the same.

[0200] Example 1-d

[0201] The procedure was carried out in accordance with Example 1, except that the type of quantum dots was different. Specifically, quaternary ZnCdSeS alloy quantum dots with bare core structure were used, while the amount remained the same.

[0202] Example 1-e

[0203] The procedure was carried out in accordance with Example 1, except that the type of boron-containing compound was different, specifically 10g of boron tribromide and 2g of 4-methylphenylboronic acid.

[0204] Example 1-f

[0205] The procedure was carried out in accordance with Example 1, except that the type of boron-containing compound was different. Specifically, it consisted of 10g of dibromohydroxyboron (which was prepared by slowly adding 3 equivalents of boron tribromide to 1 equivalent of water and partially hydrolyzing it, and was prepared and used immediately, with subsequent preparations following the same principle) and 2g of 4-methylphenylboronic acid.

[0206] Example 1-g

[0207] The procedure was carried out in accordance with Example 1, except that the types of boron-containing compounds were different, specifically 10g of 3-carboxypropylboronic acid and 2g of 4-methylphenylboronic acid.

[0208] Example 1-h

[0209] The procedure was carried out in accordance with Example 1, except that the types of boron-containing compounds were different, specifically 10g of 4-bromobutylboronic acid and 2g of 4-methylphenylboronic acid.

[0210] Example 1-i

[0211] The procedure was carried out in accordance with Example 1, except that the types of boron-containing compounds were different. Specifically, it consisted of 10g of monoethyl phenylboronic acid (obtained by controlled hydrolysis of diethyl phenylboronic acid, prepared and used immediately, with subsequent preparations following the same principle) and 2g of 4-methylphenylboronic acid.

[0212] Example 1-j

[0213] The procedure was carried out in accordance with Example 1, except that the types of boron-containing compounds were different, specifically 10g of diphenylboronic acid and 2g of 4-methylphenylboronic acid.

[0214] Example 1-k

[0215] The procedure was carried out in accordance with Example 1, except that the types of boron-containing compounds were different, specifically 10g of 4-trifluoromethylphenylboronic acid and 2g of 4-methylphenylboronic acid.

[0216] Example 1-1

[0217] The procedure was carried out in accordance with Example 1, except that the types of boron-containing compounds were different, specifically 10g of 3-aldehyde phenylboronic acid and 2g of 4-methylphenylboronic acid.

[0218] Example 1-m

[0219] The procedure was carried out in accordance with Example 1, except that the types of boron-containing compounds were different, specifically 10g of 4-carboxyphenylboronic acid and 2g of 4-methylphenylboronic acid.

[0220] Comparative Example 1

[0221] CdSe / CdS / ZnS core-shell green quantum dot octane dispersion (Em = 538 nm, Fwhm = 23 nm). The mass fraction of quantum dots in the green quantum dot octane dispersion is approximately 17%.

[0222] Comparative Example 2

[0223] A green core-shell quantum dot dispersion of CdSe / CdS / ZnS treated with organothiol metal salt (Em = 538 nm, Fwhm = 23 nm). The mass ratio of organothiol metal salt to green core-shell quantum dots is 0.6:1.

[0224] Comparative Example 3

[0225] A green core-shell quantum dot dispersion of CdSe / CdS / ZnS treated with organophosphonic acid metal salt (Em = 538 nm, Fwhm = 23 nm). The mass ratio of organophosphonic acid metal salt to green core-shell quantum dots is 0.6:1.

[0226] Comparative Example 4

[0227] CdSe / CdS / ZnS core-shell red quantum dot octane dispersion (Em = 625 nm, Fwhm = 23 nm). The mass fraction of quantum dots in the red quantum dot octane dispersion is approximately 17%.

[0228] Comparative Example 5

[0229] Octane dispersion of CdSe / CdS / ZnS core-shell red quantum dots after treatment with organothiol metal salt (Em = 625 nm, Fwhm = 23 nm); the mass ratio of organothiol metal salt to red core-shell quantum dots is 0.6:1.

[0230] Comparative Example 6

[0231] A CdSe / CdS / ZnS red core-shell quantum dot dispersion treated with organophosphonic acid metal salt (Em = 625 nm, Fwhm = 23 nm). The mass ratio of organophosphonic acid metal salt to red core-shell quantum dots is 0.6:1.

[0232] Comparative Example 9

[0233] The procedure was carried out in accordance with Example 1, except that the proportions of BX covalent bonds and BX coordinate bonds were controlled to reach the proportions shown in Table 2. To meet this condition change, the following adjustment was required: the amount of boron-containing compounds (dodecylboronic acid and 4-methylphenylboronic acid) was reduced by 90%, while the other conditions remained unchanged.

[0234] Comparative Example 10

[0235] The procedure was carried out in accordance with Example 1, except that the proportion of BX covalent bonds and BX coordination bonds was controlled to reach the proportions shown in Table 2. To meet this condition change, the amount of quantum dots was increased by 10 times, while the other conditions remained unchanged.

[0236] Test Example 1

[0237] 1. The B element content of the corresponding quantum dot dispersions (such as boron-containing quantum dot dispersions or boron-free quantum dot dispersions) obtained in the above examples and comparative examples was determined by ICP-OES (inductively coupled plasma optical emission spectrometry), and the results are shown in Tables 1-2.

[0238] And through molecular absorption spectroscopy (nuclear magnetic resonance) 11 The proportions of BX covalent bonds and BX coordination bonds in the corresponding quantum dot dispersions of each example were detected by B-spectrum analysis, and the results are shown in Tables 1-2.

[0239] 2. The corresponding quantum dot dispersions obtained in the above examples and comparative examples were used to prepare conventional quantum dot PS (polystyrene) optical sheets, which were then aged to track the changes in PLQY (i.e., photoluminescence quantum yield) of the sheets.

[0240] The preparation method of quantum dot PS optical sheet is as follows:

[0241] A certain mass of PS granules, additives (generally hindered phenolic and hindered amine antioxidants, mainly to prevent oxidation and degradation of PS during melt extrusion and in harsh environments; here, antioxidant 1010 and antioxidant 770 are compounded at a mass ratio of 2:1), and corresponding quantum dot dispersion are mixed evenly in a mixer. The mass ratio of PS granules, additives, and corresponding quantum dot dispersion is 825:8.33:1. The mixed granules are added to a micro twin-screw extruder using a feeding funnel, melt-sheared and mixed evenly, and then extruded into strips (extrusion processing temperature 260℃). The strips are then formed into sheets of 10cm×10cm×1mm using a tablet press. The mass fraction of the quantum dot dispersion is 0.12%, the mass fraction of the additives is 1%, and the mass fraction of PS is the balance.

[0242] The quantum dot PS optical sheet was subjected to aging tests under the following conditions: 85℃, 90% RH, and 800W / m². 2 Under blue light irradiance (blue light wavelength of 450nm), 1mm thick quantum dot PS optical sheets will warp, requiring clamps to secure the edges of the sheet in the aging chamber. The aging process is generally tested at intervals of 24-72 hours (subject to actual testing time). An integrating sphere is used to measure the quantum yield (PLQY) of the quantum dot PS optical sheets. The results are shown in Tables 1 and 2, and Figures 1 and 2. In Tables 1 and 2, " / " indicates that the quantum yield decrease is too large (i.e., green decrease greater than 20%, red decrease greater than 15%), at which point the test is stopped. In Tables 1 and 2, "D" represents the comparative example, and "S" represents the specific example.

[0243] The density of black and yellow spots on the board surface was measured using a CCD visual inspection instrument. A "black and yellow spot" was defined as a localized dark spot with a diameter greater than 0.1 mm that could be identified by the CCD visual inspection instrument. The results are shown in Table 1-2. In subsequent tables, the density of black and yellow spots on the board surface is represented by "β" (unit: spots / m³). 2 ).

[0244] Table 1. Test results for examples of green quantum dots.

[0245] Table 2 Test results for examples corresponding to red quantum dots

[0246] The stability data in Tables 1 and 2, and Figures 1 and 2, show that the embodiments of this disclosure prepare boron-containing quantum dot composite aggregates by treating and coating the quantum dot surface with an appropriate amount of boron-containing compound, achieving protection of anions on the quantum dot surface, resulting in good heat resistance. When using this quantum dot material to prepare quantum dot PS sheets, the stability of the quantum dots is significantly improved compared to existing technologies in the absence of a water-oxygen barrier film. It can withstand high-temperature and high-humidity blue light aging (85℃, 90% RH, 800W / m²) for over 1500 hours.2 At the same time, it also takes into account the effective avoidance of black and yellow spots.

[0247] Furthermore, adopting R8, R9, and R of this disclosure 10 R 11 They do not both contain phenyl groups; and / or, R8 and R9 are not both halogens, and R 10 R 11 Examples that are not simultaneously halogenated are more conducive to improving the stability of quantum dots, while ensuring excellent optical performance and further effectively avoiding the appearance of black and yellow spots.

[0248] 2. Preparation of boron-containing quantum dot optical diffusion plates:

[0249] Example 10

[0250] Step (1) Take 200kg PS granules, 500g green quantum dot concentrate (mass fraction ≈17%, solvent is n-octane) and 100g red quantum dot concentrate (mass fraction ≈17%, solvent is n-octane) and put them into a high-speed mixer (stirring speed is 500rpm) and stir for 3min to mix evenly to obtain a quantum dot polymer mixture for later use.

[0251] Step (2) Take 0.5 kg boric acid, 0.5 kg dodecyl boric acid, 1 kg antioxidant 1076, 0.5 kg light stabilizer 123, and 47.5 kg PS granules, mix and stir evenly, then extrude and granulate to obtain auxiliary agent granules. The extrusion temperature is 200℃. The granules are then homogenized and ready for use.

[0252] Step (3) Using a loss-in-weight balance, a uniformly mixed quantum dot polymer mixture and additive granules are added to the B-layer extruder, 25 kg of PS diffusion masterbatch is added to the A-layer extruder, and 25 kg of PS toughening masterbatch is added to the C-layer extruder. These are then extruded together to form a three-layer structure plate with AC sandwiched with B. The quantum dot concentrate content in the ABC three-layer structure plate is 0.1%, and the quantum dot mass percentage is 0.017%. The above materials are then melt-extruded at high temperature and calendered to obtain a quantum dot diffusion plate with a thickness of 1.5 mm. The melt extrusion processing temperature is 260℃, and the reaction time is 1.5 min.

[0253] Example 11

[0254] The procedure was carried out in accordance with Example 10, except that step (2) was different. Step (2) was as follows: 1 kg of boric acid, 0.7 kg of hydroxymethylbenzyl boric acid, 1 kg of antioxidant 1010, 0.5 kg of light stabilizer 770 and 46.8 kg of PS granules were mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0255] Example 12

[0256] The procedure was carried out in accordance with Example 10, except that step (2) was different. Step (2) was as follows: 1.2 kg of triethyl borate, 1.2 kg of cyclopropylboric acid, 1.2 kg of antioxidant MD-1024, 0.5 kg of light stabilizer 944 and 45.9 kg of PS granules were mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0257] Example 13

[0258] The procedure was carried out in accordance with Example 10, except that step (2) was different. Step (2) was as follows: 0.3 kg of boric acid, 0.3 kg of dodecyl boric acid, 1 kg of antioxidant 1076, 0.5 kg of light stabilizer 123 and 47.9 kg of PS granules were mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0259] Example 14

[0260] The procedure was carried out in accordance with Example 10, except that step (2) was different. Step (2) was as follows: 0.6 kg of boric acid, 0.6 kg of dodecyl boric acid, 1 kg of antioxidant 1076, 0.5 kg of light stabilizer 123 and 47.3 kg of PS granules were mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0261] Example 15

[0262] The procedure was carried out in accordance with Example 10, except that step (2) was different. Step (2) was as follows: 1.2 kg of boric acid, 1.2 kg of dodecyl boric acid, 1 kg of antioxidant 1076, 0.5 kg of light stabilizer 123 and 46.1 kg of PS granules were mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0263] Example 16

[0264] The procedure was carried out in accordance with Example 10, except that step (2) was different. Step (2) was as follows: 2 kg of boric acid, 2 kg of dodecyl boric acid, 1 kg of antioxidant 1076, 0.5 kg of light stabilizer 123 and 44.5 kg of PS granules were mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0265] Example 10-a

[0266] The procedure was carried out in accordance with Example 10, except that the melt extrusion processing temperature in step (3) was increased until the proportions of BX covalent bonds and BX coordinate bonds reached the ratios shown in Table 5. The chemical structures of the tricoordinate boron-containing quantum dot complex and the tetracoordinate boron-containing quantum dot complex contained in the product remained unchanged.

[0267] Example 10-b

[0268] The procedure was carried out in accordance with Example 10, except that the melt extrusion processing temperature in step (3) was reduced until the proportions of BX covalent bonds and BX coordinate bonds were controlled to meet the ratios shown in Table 5. The chemical structures of the tricoordinate boron-containing quantum dot complex and the tetracoordinate boron-containing quantum dot complex contained in the product remained unchanged.

[0269] Example 10-c

[0270] The procedure was carried out in accordance with Example 10, except that the type of quantum dots was different; specifically, core-shell structured CdZnSe / ZnSe / ZnS quantum dots were used instead, while the amount remained the same. The chemical structures of the tricoordinate boron-containing quantum dot complex and the tetracoordinate boron-containing quantum dot complex contained in the product remained unchanged.

[0271] Example 10-d

[0272] The procedure was carried out in accordance with Example 10, except that the type of quantum dots was different; specifically, quaternary ZnCdSeS alloy quantum dots with a bare core structure were used, while the amount remained the same. The chemical structures of the tri-coordinate boron-containing quantum dot complex and the tetra-coordinate boron-containing quantum dot complex contained in the product remained unchanged.

[0273] Example 10-e

[0274] The procedure was carried out in accordance with Example 10, except that the amount of boric acid used in step (2) was adjusted to 0 kg and the amount of dodecylboric acid used was 1 kg. In this example, the mass of the boron-containing compound used for coordination bonding with other lone pair electron or conjugated electron donors in the raw material other than quantum dots was 900% of the mass of the quantum dots.

[0275] Example 17

[0276] The procedure was carried out in accordance with Example 10, except that boron tribromide was used instead of boric acid in step (2), while the amount remained the same.

[0277] Example 18

[0278] The procedure was carried out in accordance with Example 10, except that in step (2), 4-methylphenylboronic acid was used instead of boric acid, while the amount remained the same.

[0279] Example 19

[0280] The procedure was carried out in accordance with Example 10, except that in step (2), 3-carboxypropylboronic acid was used instead of boric acid, while the amount remained the same.

[0281] Example 20

[0282] The procedure was carried out in accordance with Example 10, except that in step (2), 4-bromobutylboronic acid was used instead of boric acid, while the amount remained the same.

[0283] Example 21

[0284] The procedure was carried out in accordance with Example 10, except that hydroxypropyl boric acid was used instead of boric acid in step (2), while the amount remained the same.

[0285] Example 22

[0286] The procedure was carried out in accordance with Example 10, except that diethyl borate was used instead of boric acid in step (2), while the amount remained the same.

[0287] Example 23

[0288] The procedure was carried out in accordance with Example 10, except that in step (2), phenylboronic acid monoethyl ester was used instead of boric acid, while the amount remained the same.

[0289] Example 24

[0290] The procedure was carried out in accordance with Example 10, except that in step (2), 4-trifluoromethylphenylboronic acid was used instead of boric acid, while the amount remained the same.

[0291] Example 25

[0292] The procedure was carried out in accordance with Example 10, except that in step (2), β,B-bis(4-fluorophenyl)boronic acid was used instead of boric acid, while the amount remained the same.

[0293] Example 26

[0294] The procedure was carried out in accordance with Example 10, except that in step (2), 3-aldehyde phenylboronic acid was used instead of boric acid, while the amount remained the same.

[0295] Example 27

[0296] The procedure was carried out in accordance with Example 10, except that in step (2), 4-carboxyphenylboronic acid was used instead of boric acid, while the amount remained the same.

[0297] Comparative Example 7

[0298] The same procedure was followed as in Example 10, except that the types of quantum dots were the same and the total amount was the same, but no boron-containing compounds were added. Specifically, in step (2), only 1 kg of antioxidant 1076, 0.5 kg of light stabilizer 123, and 48.5 kg of PS granules were added, mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0299] Comparative Example 8

[0300] The same procedure was followed as in Example 10, except that the types of quantum dots were the same and the total amount was the same, but thiols and phosphates were used instead of boron compounds. Specifically, in step (2), 0.5 kg of zinc octyl thiol salt, 0.5 kg of zinc dodecyl phosphonate salt, 1 kg of antioxidant 1076, 0.5 kg of light stabilizer 123, and 47.5 kg of PS granules were mixed and stirred evenly, and then extruded and granulated to obtain the additive granules, which were then prepared for use.

[0301] Comparative Example 11

[0302] The procedure was carried out in accordance with Example 10, except that the proportion of BX covalent bonds and BX coordinate bonds was controlled to reach the proportions shown in Table 5. To meet this condition change, it is necessary to adjust the amount of boron compound used in step (2). Step (2) is as follows: Take 0.03 kg of boric acid, 0.03 kg of dodecyl boric acid, 1 kg of antioxidant 1076, 0.5 kg of light stabilizer 123, and 48.44 kg of PS granules, mix and stir evenly, and then extrude and granulate to obtain auxiliary granules. The granules are then homogenized and ready for use.

[0303] The products of the above embodiments and comparative examples were subjected to corresponding absorption spectra (nuclear magnetic resonance) tests. 11 B-spectroscopy analysis showed that the three-coordinate boron-containing quantum dot complexes and the four-coordinate boron-containing quantum dot complexes correspond to Formula 1 and Formula 2, respectively, as shown in Tables 3-1 and 3-2. Only the most basic structure of the corresponding general formulas is shown here, excluding derived forms. The product is chain-like, and n1 and n2 are natural numbers, calculated based on theoretical values ​​of the feed.

[0304] Table 3-1 Chemical structures of triligand boron-containing quantum dot complexes

[0305] Table 3-2 Chemical structures of tetraligand boron-containing quantum dot complexes

[0306] Test Example 2

[0307] Taking Comparative Examples 7-8 and Examples 10-12 as examples, aging tests were conducted on the quantum dot PS optical diffusion plates prepared on the corresponding production lines. The test conditions were 85°C, 90% RH, and 800 W / m². 2 Blue light irradiance (blue light wavelength of 450nm), the aging process test time is generally 100-200h interval, and the color coordinates x, y and luminance Lv value of the quantum dot PS optical diffusion plate are measured using a color analyzer. The results are shown in Figure 3 (change of color coordinate x), Figure 4 (change of color coordinate y), and Figure 5 (change of luminance Lv value).

[0308] The same aging tests were performed on Examples 13-16 as described above. The initial values ​​before aging and the test results after the last aging for Examples 13-16 and Comparative Example 8 are shown in Table 4. Here, Δx and Δy are the differences between the chromaticity coordinate X value after aging and the chromaticity coordinate X value before aging, respectively, and the differences between the chromaticity coordinate Y value after aging and the chromaticity coordinate Y value before aging. If a decrease occurs, Δx and Δy are negative. ΔLv% is calculated as (brightness Lv value after aging - brightness Lv value before aging) / brightness Lv value before aging.

[0309] Table 4

[0310] The data in Figures 3-5 and Table 4 above show that: the embodiments of this disclosure use an appropriate amount of boron-containing compound to prepare quantum dot optical diffusion plates, which have good heat resistance and achieve the coating of quantum dots by boron-containing compound during the extrusion process; compared with the prior art (without boron compound), this disclosure significantly improves the stability of quantum dot optical diffusion plates and ensures excellent optical performance. Among them, the optical performance and stability of Examples 13 / 14 / 15 / 16 are basically comparable to the level of Example 10, with Example 13 being slightly worse than Example 10, and the optical performance and stability of Examples 14 / 15 / 16 gradually improving.

[0311] Test Example 3

[0312] For the quantum dot PS optical diffusion plates prepared on the production lines corresponding to the above comparative examples and embodiments, the elemental B of different quantum dot diffusion plates was measured using ICP-OES, and the results are shown in Table 5.

[0313] The density of black and yellow spots on the board surface was measured using the same method as in Test Example 1, and the results are shown in Table 5. The density of black and yellow spots on the board surface will be represented by "β" in subsequent tables.

[0314] And through molecular absorption spectroscopy (nuclear magnetic resonance) 11 The proportions of BX covalent bonds and BX coordinate bonds in the quantum dot PS optical diffuser plates of each example were detected by B-spectrum analysis, and the results are shown in Table 5.

[0315] Table 5

[0316] The data in Figures 3-5 and Tables 4-5 above show that: the embodiments of this disclosure use an appropriate amount of boron-containing compound to prepare quantum dot optical diffusion plates, which have good heat resistance, significantly improve the stability of quantum dot optical diffusion plates, ensure excellent optical performance, and effectively avoid the appearance of black and yellow spots.

[0317] Furthermore, as can be seen from Examples 10 and 13-16 and the data in Tables 4 and 5, the stability of the quantum dot optical diffusion plate in the embodiments of this disclosure is positively correlated with the amount of boron-containing compound (mass content of boron). When the boron content is within a suitable range, the stability gradually increases, which fully demonstrates the protection of the optical properties of quantum dots by the boron-containing compound.

[0318] The preferred embodiments of this disclosure have been described in detail above; however, this disclosure is not limited thereto. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in this disclosure and are all within the protection scope of this disclosure. Industrial applicability

[0319] This disclosure utilizes boron-containing compound-stabilized quantum dots to form three-coordinate and four-coordinate boron-containing quantum dot complexes with suitable boron content. Since boron has more valence orbitals (4) than valence bond electrons (3), boron primarily functions as sp electrons when forming neutral compounds with quantum dots. 2 Hybridization forms a planar tricoordinate boron-containing quantum dot complex with one empty p orbital. This gives the tricoordinate boron compound a significant electron-deficient property, making it susceptible to attack from electron-rich groups and forming a tetracoordinate boron-containing quantum dot complex. Therefore, the boron compound can act as a Z-type ligand to bind to the anions on the quantum dot surface, providing more stable protection. The boron compound exhibits good heat resistance while ensuring excellent optical properties, effectively preventing the formation of black and yellow spots. Furthermore, by controlling the ratio of XB coordination bonds to the sum of XB covalent bonds and XB coordination bonds in the boron-containing quantum dot complex aggregates within an appropriate range, the strong binding ability of the tricoordinate boron-containing quantum dot complex and the strong oxidation resistance of the tetracoordinate boron-containing quantum dot complex can be fully utilized. This approach better balances strong binding ability and oxidation resistance, resulting in better heat resistance, stability, and longer lifespan, further effectively preventing the formation of black and yellow spots. Compared to existing quantum dot composites, this disclosure significantly improves the stability of quantum dots. The fundamental principle is that boron-containing compounds (especially electron-deficient three-coordinate boron compounds) can act as ligands to protect the quantum dot anions, forming three-coordinate and four-coordinate boron-containing quantum dot composites with suitable boron content, thereby enhancing the stability of the quantum dots. This disclosure has a wide range of applications and shows promising potential in electroluminescence applications.

Claims

1. A boron-containing quantum dot composite aggregate, characterized by, The application relates to a three-coordinated boron-containing quantum dot complex and a four-coordinated boron-containing quantum dot complex formed by chemical bonding of a boron-containing compound and quantum dots, the boron-containing compound and the quantum dots are covalently bonded in the three-coordinated boron-containing quantum dot complex, the boron-containing compound and the quantum dots are coordinately bonded in the four-coordinated boron-containing quantum dot complex, the proportion of the number of X-B coordination bonds to the sum of the number of X-B covalent bonds and the number of X-B coordination bonds in the boron-containing quantum dot complex aggregate is 0.10%-50%, and X is selected from X1, X2, X3, X4, X5 and X6; wherein, the chemical general formula of the three-coordinated boron-containing quantum dot complex is formula I, and the chemical general formula of the four-coordinated boron-containing quantum dot complex is formula II. wherein QD is a quantum dot; R8, R9, R 10 , R 11 , R 12 , R 13 are each independently selected from alkoxy, hydrocarbyl, substituted hydrocarbyl, halogen, carboxyl, hydroxyl, aldehyde, ester, amide, and the substituents in substituted hydrocarbyl are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, amide; n1 = natural number, n2 = natural number; X1, X2, X3, X4, X5, X6 are each independently selected from Group VIA element, Group VA element, Group IVA element.

2. The boron-containing quantum dot complex aggregate of claim 1, wherein, The boron-containing quantum dot complex aggregate is a boron-containing quantum dot dispersion liquid, and the content of boron in the boron-containing quantum dot dispersion liquid is 1000 ppm-9000 ppm.

3. The boron-containing quantum dot complex aggregate according to claim 1 or 2, wherein The boron-containing quantum dot complex aggregate is a boron-containing quantum dot composite board, and the content of boron in the boron-containing quantum dot composite board is 13 ppm-1750 ppm.

4. The boron-containing quantum dot complex aggregate according to any one of claims 1 to 3, wherein X1, X2, X3, X4, X5, X6 are each independently selected from O, S, Se, Te, N, P, As, C, Si, Ge; and / or, R8, R9, R 10 , R 11 , R 12 , R 13 are each independently selected from the group consisting of alkoxy group having 1 to 18 carbon atoms, hydrocarbon group having 1 to 18 carbon atoms, substituted hydrocarbon group having 1 to 18 carbon atoms, halogen, carboxyl group, hydroxyl group, aldehyde group, ester group, amide group; the hydrocarbon group having 1 to 18 carbon atoms is selected from the group consisting of alkyl group having 1 to 18 carbon atoms, aryl group having 6 to 18 carbon atoms, alkenyl group having 2 to 18 carbon atoms, alkynyl group having 2 to 18 carbon atoms.

5. The boron-containing quantum dot complex aggregate according to any one of claims 1 to 4, wherein X1, X2, X3, X4, X5, X6 are each independently selected from O and S; and / or, R8, R9, R 10 , R 11 , R 12 , R 13 are each independently selected from the group consisting of alkoxy of 1 to 18 carbon atoms, alkyl of 1 to 18 carbon atoms, aryl or substituted aryl of 6 to 18 carbon atoms, hydroxy; The substituent group in the substituted aryl group with 6-18 carbon atoms is selected from at least one of alkyl, hydroxyalkyl, alkoxy, halogen, carboxyl, aldehyde group.

6. The boron-containing quantum dot complex aggregate according to any one of claims 1 to 5, wherein, R8 and R9 are each independently selected from hydroxyl, alkoxy with 1-18 carbon atoms, alkyl with 1-18 carbon atoms, aryl or substituted aryl with 6-18 carbon atoms, wherein if R8 or R9 is selected from substituted aryl with 6-18 carbon atoms, the substituent group in the substituted aryl group is selected from at least one of alkyl, hydroxyalkyl and halogen; R 10 , R 11 , R 12 , R 13 are each independently of the others selected from the group consisting of hydroxy, alkoxy having 1 to 18 carbon atoms, alkyl having 1 to 18 carbon atoms, aryl or substituted aryl having 6 to 18 carbon atoms, wherein R 10 , R 11 , R 12 or R 13 are selected from substituted aryl having 6 to 18 carbon atoms, then the substituents in the substituted aryl are selected from at least one of alkoxy, hydroxyalkyl, alkyl and halogen.

7. The boron-containing quantum dot complex aggregate according to any one of claims 1 to 6, wherein, The tri-coordinated boron-containing quantum dot complex is selected from at least one of: The tetra-coordinated boron-containing quantum dot complex is selected from at least one of: at least one of:

8. The boron-containing quantum dot complex aggregate according to any one of claims 1 to 7, wherein, The quantum dot is a bare core structure, and the surface of the bare core structure has at least one of group IVA atoms, group VA anions and group VIA anions.

9. The boron-containing quantum dot complex aggregate according to any one of claims 1 to 8, wherein, The quantum dot is a core-shell structure, and the shell surface of the core-shell structure contains at least one of group IVA atoms, group VA anions and group VIA anions.

10. A method for producing a boron-containing quantum dot dispersion liquid, characterized by, The method comprises the following steps: S1, preparing a boron-containing compound and a dispersion solvent; S2, adding quantum dots to the system of the boron-containing compound and the dispersion solvent and introducing inert gas; S3, heating, mixing and dispersing the system obtained in S2 and performing heat preservation reaction; during the reaction, a three-coordination boron-containing quantum dot complex and a four-coordination boron-containing quantum dot complex are formed through the reaction of the boron-containing compound and the quantum dots, the boron-containing compound and the quantum dots are covalently connected in the three-coordination boron-containing quantum dot complex, the boron-containing compound and the quantum dots are coordinately connected in the four-coordination boron-containing quantum dot complex, and the proportion of X-B coordination bond in the sum of X-B covalent bond and X-B coordination bond in the boron-containing quantum dot dispersion liquid is 0.10%-50%, X is selected from X1, X2, X3, X4, X5 and X6; S4, cooling; In S3, the chemical general formula of the three-coordinated boron-containing quantum dot complex is as follows: Formula I, and the chemical general formula of the four-coordinated boron-containing quantum dot complex is as follows: Formula II. In Formula I and Formula II, QD is a quantum dot; R8, R9, R 10 , R 11 , R 12 , R 13 are each independently selected from alkoxy, hydrocarbyl, substituted hydrocarbyl, halogen, carboxyl, hydroxyl, aldehyde, ester, amide, the substituents in substituted hydrocarbyl are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, amide, n1 = natural number, n2 = natural number, X1, X2, X3, X4, X5, X6 are each independently selected from Group VIA element, Group VA element, Group IVA element.

11. The method for preparing a boron-containing quantum dot dispersion liquid according to claim 10, characterized by, The content of boron in the boron-containing quantum dot dispersion liquid is 1000 ppm-9000 ppm.

12. The method for producing a boron-containing quantum dot dispersion liquid according to claim 10 or 11, characterized by, In S2, the mass ratio of the quantum dots to the boron-containing compound is 1:0.25-5, and / or in S1, the mass ratio of the boron-containing compound to the dispersion solvent is 0.01-0.5:

1.

13. The method for producing a boron-containing quantum dot dispersion liquid according to any one of claims 10 to 12, characterized by, In S1, the dispersion solvent comprises at least one of alkane, arene, organic amine, octadecene, organic carboxylic acid with 1-18 carbon atoms, liquid paraffin, acrylate, organosilane and organophosphine. And / or in S3, the reaction temperature of the heat preservation reaction is higher than the melting point of the system of the boron-containing compound and the dispersion solvent and lower than the boiling point of the system of the boron-containing compound and the dispersion solvent, the reaction time is 0.1 h-3 h, and the stirring speed of the mixing and dispersing is 100 rpm-300 rpm.

14. The method for producing a boron-containing quantum dot dispersion liquid according to any one of claims 10 to 13, characterized by, When the proportion of covalent bond needs to be increased, the reaction temperature in S3 is controlled to be 100-300℃; when the proportion of coordination bond needs to be increased, the reaction temperature in S3 is controlled to be 30-100℃ and not equal to 100℃.

15. The method for producing a boron-containing quantum dot dispersion liquid according to any one of claims 10 to 14, characterized by, The quantum dots are of core-shell structure or bare core structure, and the quantum dots exist in solid or concentrated liquid form, and the solid content mass fraction of the quantum dots in the concentrated liquid is 5-50%.

16. The method for producing a boron-containing quantum dot dispersion liquid according to any one of claims 10 to 15, characterized by, The boron-containing compound includes at least one of the following three general compounds and their dehydration condensation, esterification, amidation derivative compounds: General Formula One, R1, R2, R3are each independently selected from the group consisting of hydrocarbyl, alkoxy, halogen, substituted hydrocarbyl; general formula two, R4, R5 are each independently selected from carboxyl, substituted hydrocarbon group, halogen, hydrocarbon group, alkoxy, hydroxyl; General Formula III, R6 is selected from H or selected from substituted hydrocarbon group, halogen, aldehyde group, carboxyl, and R7 is selected from hydrocarbon group, alkoxy, hydroxyalkyl, hydroxyl; In the three general compounds, the substituents in the substituted hydrocarbon group are each independently selected from at least one of halogen, hydroxyl, alkoxy, carboxyl, aldehyde group, ester group, amide group.

17. The method for producing a boron-containing quantum dot dispersion liquid according to any one of claims 10 to 16, characterized by, The boron-containing compound at least includes the third general formula; And / or, the number of carbon atoms in any carbon-containing group in the first general formula, the second general formula and the third general formula is less than 18, wherein the hydrocarbon group is selected from alkyl, aryl, alkenyl and alkynyl.

18. A boron-containing quantum dot dispersion, characterized in that, The boron-containing quantum dot dispersion liquid is prepared by the preparation method of the boron-containing quantum dot dispersion liquid according to any one of claims 10-17.

19. A method for preparing a boron-containing quantum dot composite board, characterized by, The method comprises the following steps: S101, providing a boron-containing compound, a quantum dot concentrate, a polymer pellet, and a plate functional additive; S102, mixing the quantum dot concentrate with at least part of the polymer pellet to obtain a quantum dot polymer mixture; S103, melt extruding the quantum dot polymer mixture, the boron-containing compound and the plate functional additive to form a boron-containing quantum dot composite plate; during the melt extrusion, the boron-containing compound reacts with the quantum dots to form a three-coordination boron-containing quantum dot composite and a four-coordination boron-containing quantum dot composite, the boron-containing compound in the three-coordination boron-containing quantum dot composite is covalently bonded to the quantum dots, the boron-containing compound in the four-coordination boron-containing quantum dot composite is coordinately bonded to the quantum dots, the proportion of X-B coordination bond to the sum of X-B covalent bond and X-B coordination bond in the boron-containing quantum dot composite plate is 0.10%-50%, and X is selected from X1, X2, X3, X4, X5 and X6; In S103, the three-coordinated boron-containing quantum dot complex has a chemical formula as shown in Formula I below, and the four-coordinated boron-containing quantum dot complex has a chemical formula as shown in Formula II below. wherein QD is a quantum dot; R8, R9, R 10 , R 11 , R 12 , R 13 are each independently selected from alkoxy, hydrocarbyl, substituted hydrocarbyl, halogen, carboxyl, hydroxyl, aldehyde, ester, amide, the substituents in substituted hydrocarbyl are selected from at least one of halogen, hydroxyalkyl, alkyl, hydroxyl, alkoxy, carboxyl, aldehyde, ester, amide, n1 = natural number, n2 = natural number, X1, X2, X3, X4, X5, X6 are each independently selected from group VIA element, group VA element, group IVA element.

20. The method for preparing the boron-containing quantum dot composite plate according to claim 19, characterized in that, The content of boron element in the boron-containing quantum dot composite plate is 13-1750 ppm; And / or, the mass ratio of the total amount of quantum dots and boron-containing compounds is 1:(0.5-40), and the mass of the boron-containing compound used for coordination combination with other lone pair electron or conjugate electron donors in the raw material except the quantum dots is 1.2%-1000% of the mass of the quantum dots.

21. The method for preparing a boron-containing quantum dot composite plate according to claim 19 or 20, characterized in that, The melt extrusion process of S103 includes: second mixing extrusion of the boron-containing compound, the antioxidant, the light stabilizer and another part of the polymer pellet to obtain an additive pellet; then, the quantum dot polymer mixture and the additive pellet are put into a first extruder, the diffusion agent and the toughening agent are respectively put into a second extruder and a third extruder, and then melt extrusion is performed; wherein the temperature of the second mixing extrusion is 180-220℃.

22. The method of claim 19-21, wherein the method further comprises the step of: The melt extrusion conditions of S103 include: the processing temperature is 210-270℃, and the reaction time is 1-2 min; ​ And / or, the stirring speed of the first mixing in S102 is 300-700 rpm.

23. The method for preparing a boron-containing quantum dot composite plate according to any one of claims 19 to 22, characterized in that, The boron-containing quantum dot composite plate is a boron-containing quantum dot optical diffusion plate, and the corresponding plate functional additives include at least one of an antioxidant, a light diffuser, a toughening agent, and a light stabilizer; the quantum dots include red quantum dots and / or green quantum dots, and the high molecular particle is selected from polystyrene, polymethyl methacrylate, polycarbonate, polyethylene, and polypropylene; wherein the thickness of the boron-containing quantum dot composite plate is 1.2-3.0 mm. And / or, in S101, the mass fraction of the boron-containing compound is 0.05%-1% based on the total amount of raw materials, the mass fraction of the quantum dot concentrate is 0.05%-0.2%, the mass fraction of the quantum dots in the quantum dot concentrate is 5%-50%, the mass fraction of the antioxidant is 0.1%-2%, the total mass fraction of the light diffuser and the toughening agent is 0.5%-2%, and the mass fraction of the light stabilizer is 0.05%-2%.

24. The method of claim 19-23, wherein the method further comprises the step of: The boron-containing compound includes at least one of the following three general compounds and their dehydration condensation, esterification, and amidation derivatives: ​ General Formula One, R1, R2, and R3 are each independently selected from a hydrocarbon group, an alkoxy group, a halogen, and a substituted hydrocarbon group; Formula II R4 and R5 are each independently selected from a carboxyl group, a substituted hydrocarbon group, a halogen, a hydrocarbon group, an alkoxy group, and a hydroxyl group; General Formula Three, R6 is selected from H or a substituted hydrocarbon group, a halogen, an aldehyde group, a carboxyl group, and a hydroxyl alkyl group, and R7 is selected from a hydrocarbon group, an alkoxy group, a hydroxyl alkyl group, and a hydroxyl group; In the three general compounds, the substituents in the substituted hydrocarbon group are each independently selected from at least one of a halogen, a hydroxyl alkyl group, an alkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an aldehyde group, an ester group, and an amide group.

25. The method for preparing a boron-containing quantum dot composite plate according to any one of claims 19 to 24, characterized in that, The boron-containing compound at least includes the third general formula. And / or, the number of carbon atoms in any carbon-containing group in the first general formula, the second general formula, and the third general formula is less than 18, wherein the hydrocarbon group is selected from an alkyl group, an aryl group, an alkenyl group, and an alkinyl group.

26. A boron-containing quantum dot composite panel, comprising: The boron-containing quantum dot composite plate is prepared by the preparation method of any one of claims 19-25.

27. An application of the boron-containing quantum dot composite aggregate of any one of claims 1-9 in a quantum dot diffusion plate, a quantum dot light conversion agricultural film, a quantum dot on-chip packaging, and a quantum dot electroluminescent device.

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