Surface modified quantum dots, quantum dot composites and preparation methods thereof, and quantum dot products

Abstract

The present application provides surface-modified quantum dots, quantum dot complexes, and methods for preparing the same, as well as quantum dot products. The surface-modified quantum dots of the present application include a quantum dot body and an organic ligand modified on the surface of the quantum dot body, wherein the organic ligand is derived from an epoxysiloxane-polythiol compound, and the organic ligand comprises at least one thiol terminal group and several siloxane terminal groups, and the epoxysiloxane-polythiol compound is obtained by reacting polythiol with epoxysiloxane. The organic ligands from the epoxysiloxane-polythiol compound in the quantum dots can undergo hydrolysis and polycondensation reactions to form a quantum dot complex having an interpenetrating network structure, and the interpenetrating network structure effectively protects the quantum dots from water, oxygen, high temperature, and strong blue light, and the quantum dot products prepared from the quantum dot complex have excellent optical properties.

Description

Technical Field

[0001] The present application belongs to the field of nanomaterial technology, and specifically relates to surface-modified quantum dots, quantum dot composites and preparation methods thereof, and quantum dot products. Background Art

[0002] Quantum dots, also known as semiconductor nanocrystals, are a new type of semiconductor nanomaterial with a size of 1-10nm. Due to the quantum size effect and dielectric confinement effect, they have unique photoluminescence (PL) and electroluminescence (EL) properties. Compared with traditional organic fluorescent dyes, quantum dots have high quantum yield, high photochemical stability, not easy to photolyze, as well as wide excitation, narrow emission, high color purity, and the luminescent color can be adjusted by controlling the particle size of quantum dots. Excellent optical properties have broad application prospects in the display field. Among them, quantum dot photoluminescent film has become a research hotspot as one of the most concerned applications at present.

[0003] At present, since quantum dots are not resistant to water, oxygen, high temperature, and high-energy blue light, the quantum dot photoluminescent film prepared from them has poor stability, which is not conducive to the industrialization of quantum dot photoluminescent film and seriously restricts the development of quantum dot photoluminescent film. Summary of the invention

[0004] In response to the above technical problems, the present application provides a surface-modified quantum dot, comprising a quantum dot body and an organic ligand modified on the surface of the quantum dot body, wherein the organic ligand is derived from an epoxysiloxane-polythiol compound, and the organic ligand comprises at least one thiol end group and several siloxane end groups, and the epoxysiloxane-polythiol compound is obtained by the reaction of the thiol group of the polythiol with the epoxy group of the epoxysiloxane.

[0005] Further, the polythiol is at least one of pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate), tris [2- (3-mercaptopropionyloxy) ethyl] isocyanurate, 1,6-hexanedithiol, 2,3-dimercapto-1-propanol, propane-1,2,3-trithiol, 2-mercaptoethyl ether, 2-mercaptoethyl sulfide, 1,8-octanedithiol, 1,8-dimercapto-3,6-dithia-octane and trithiocyanic acid.

[0006] Furthermore, the molar ratio of the polythiol to the epoxysiloxane is 1:(0.5-4).

[0007] The present application also provides a quantum dot composite, comprising a quantum body and an interpenetrating network structure coated and connected to the quantum dot body, wherein the interpenetrating network structure is formed by hydrolysis and condensation of the organic ligands of a plurality of the surface-modified quantum dots as described above.

[0008] The present application also provides a method for preparing a quantum dot composite, comprising the steps of:

[0009] S1. At 20-60° C., a polythiol and an epoxysiloxane are subjected to a ring-opening reaction to form an epoxysiloxane-polythiol compound;

[0010] S2, reacting the epoxysiloxane-polythiol compound with the initial quantum dots at 60-120° C. to form surface-modified quantum dots, wherein the surface of the surface-modified quantum dots is modified with an organic ligand, and the organic ligand is derived from the epoxysiloxane-polythiol compound;

[0011] S3. At 60-140° C., the organic ligands in the surface-modified quantum dots undergo a hydrolysis-condensation reaction to form a quantum dot complex having an interpenetrating network structure.

[0012] Furthermore, the mass ratio of the epoxysiloxane-polythiol compound to the initial quantum dots is (0.1-20):1.

[0013] Furthermore, the reaction in step S3 is carried out in the presence of an amine.

[0014] Furthermore, the reaction system of step S3 contains organic aluminum and / or aluminum salt.

[0015] Furthermore, step S1 and / or step S2 are performed under an inert atmosphere.

[0016] The present application also provides a quantum dot product, comprising the above-mentioned quantum dot complex or the quantum dot complex prepared by the above-mentioned quantum dot complex preparation method.

[0017] Beneficial effects: The quantum dots of the present application are surface-modified with organic ligands, the organic ligands are derived from epoxysiloxane-polythiol compounds, the epoxysiloxane-polythiol compounds contain at least one thiol terminal group and several oxane terminal groups, and are obtained by a ring-opening reaction between polythiol and epoxysiloxane. The organic ligands from the epoxysiloxane-polythiol compounds in the quantum dots can undergo a hydrolysis and polycondensation reaction to form a quantum dot complex with an interpenetrating network structure. The interpenetrating network structure effectively protects the quantum dots from water, oxygen, high temperature, and strong blue light. The silicon groups contained in the quantum dots further enhance the temperature resistance of the quantum dots. Polythiol effectively improves the blue light tolerance performance. The quantum dot products prepared from the quantum dot complex have excellent optical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a reaction mechanism diagram of the quantum dot complex of Example 1 of the present application. DETAILED DESCRIPTION

[0019] The following will describe the technical solutions in the embodiments of the present application in detail in combination with the embodiments of the present application. It should be noted that the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0020] As described in the background art, the development of quantum dot photoluminescent films is severely restricted in the prior art due to the poor stability of the quantum dot photoluminescent films.

[0021] Based on this, the present application provides a surface-modified quantum dot, which includes a quantum dot body and an organic ligand modified on the quantum dot body, wherein the organic ligand is from an epoxysiloxane-polythiol compound, and the organic ligand includes at least one thiol terminal group and several siloxane terminal groups away from the quantum dot body, and the epoxysiloxane-polythiol compound is obtained by reacting the thiol of the polythiol with the epoxy group of the epoxysiloxane. The thiol on the epoxysiloxane-polythiol compound formed by the ring-opening reaction of the thiol of the polythiol with the epoxy group of the epoxysiloxane is easy to coordinate and connect on the quantum dot body, thereby obtaining a surface-modified quantum dot, and several oxane terminal groups on the organic ligand in the surface-modified quantum dot will undergo a hydrolysis reaction, and after the hydrolysis, the organic ligands will undergo a polycondensation reaction with each other, thereby forming an interpenetrating network structure, and the interpenetrating network structure is coated and connected on the surface of the quantum body to effectively protect the quantum dot body from damage by water oxygen, excessive blue light, and high temperature.

[0022] In a specific embodiment of the present application, the polythiol is at least one of pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate), tris [2- (3-mercaptopropionyloxy) ethyl] isocyanurate, 1,6-hexanedithiol, 2,3-dimercapto-1-propanol, propane-1,2,3-trithiol, 2-mercaptoethyl ether, 2-mercaptoethyl sulfide, 1,8-octanedithiol, 1,8-dimercapto-3,6-dithiaoctane and trithiocyanic acid. A portion of the thiol groups in the polythiol are used for ring-opening reaction with epoxysiloxane, and another portion of the thiol groups can form a coordination connection with the surface of the quantum dots, which is beneficial for the quantum dots to be coated by the interpenetrating network structure when preparing the quantum dot composite, thereby significantly enhancing the stability of the quantum dots.

[0023] In a specific embodiment of the present application, the epoxysiloxane is at least one of 3-glycidyloxypropyltriethoxysilane, (3-glycidyloxypropyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis[2-(3,4-epoxycyclohexyl-1-yl)ethyl]tetramethyldisiloxane, 1,3-bis(3-glycidyloxypropyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis[2-(3,4-epoxycyclohexyl)ethyl]tetramethyldisiloxane, epoxy-terminated phenyltrisiloxane, tetraepoxycyclosiloxane, and hexamethylcyclotrisiloxane, so as to facilitate effective ring-opening reaction with polythiol.

[0024] In another specific embodiment of the present application, the molar ratio of polythiol to epoxysiloxane is 1:(0.5-4), so that the subsequent reaction performance of the formed surface ligand is better.

[0025] The present application also provides a quantum dot complex having an interpenetrating network structure, which is formed by hydrolysis and condensation between the organic ligands of the above-mentioned surface-modified quantum dots. The interpenetrating network structure wraps the quantum dot body, providing good protection for the quantum dot body and effectively avoiding the adverse effects of water vapor, oxygen, temperature, and blue light on the quantum dot body.

[0026] The present application also provides a method for preparing a quantum dot composite, comprising the following steps:

[0027] S1. reacting polythiol with epoxysiloxane at 20-60° C. to form an epoxysiloxane-polythiol compound;

[0028] The epoxysiloxane-polythiol compound is obtained by a ring-opening reaction between polythiol and epoxysiloxane, in which a mercapto group and an epoxy group undergo a ring-opening reaction, and the formed epoxysiloxane-polythiol compound contains at least one mercapto terminal group and a plurality of oxane terminal groups.

[0029] In step S1 of the present application, the viscosity difference of the system before and after the reaction is greater than 50 cp to obtain a fully reacted epoxysiloxane-polythiol compound.

[0030] S2. Fully reacting the epoxysiloxane-polythiol compound with the initial quantum dots in a solvent at 60-120° C. to form surface-modified quantum dots, wherein the surface of the surface-modified quantum dots is modified with an organic ligand, and the organic ligand comes from the epoxysiloxane-polythiol compound;

[0031] The mercapto groups in the epoxysiloxane-polythiol compound will undergo coordination reaction and / or ligand exchange reaction with the initial quantum dots, thereby making the organic ligand connection stability on the surface of the modified quantum dots stronger.

[0032] S3. At 60-140° C., the organic ligands in the surface-modified quantum dots undergo a hydrolysis-condensation reaction to form a quantum dot complex having an interpenetrating network structure.

[0033] The oxyalkyl end groups of the organic ligands undergo hydrolysis and polycondensation to form an interpenetrating network structure. The interpenetrating network structure in the quantum dot complex wraps around the quantum dot body, providing good protection for the quantum dot body and enhancing the stability of the quantum dot body.

[0034] An exemplary reaction mechanism of the interpenetrating network structure of the present application is, for example, the reaction of the thiol groups from polythiol with the epoxy groups from epoxysiloxane, and then the interpenetrating network structure containing polythiol groups can be generated by hydrolyzing and condensing the siloxane groups. Some of the thiol groups in the interpenetrating network structure will be coordinated on the quantum dot body, and the interpenetrating network structure will be coated and connected to the quantum dots, thereby effectively protecting the quantum dots from the influence of high temperature, high humidity and high blue light.

[0035] In another specific embodiment of the present application, the mass ratio of the epoxysiloxane-polythiol compound to the initial quantum dots is (0.1-20):1, so that the interpenetrating network structure formed is more solid, and the water and oxygen barrier properties of the quantum dot composite are better and the tolerance to high temperature is stronger.

[0036] In another specific embodiment of the present application, the solvent is selected from but not limited to at least one of n-heptane, cyclohexane, n-hexane, xylene, and chloroform. Such solvents can better dissolve polythiol, epoxysiloxane, initial quantum dots, and modified quantum dots, and promote the efficient ring-opening reaction and hydrolysis-condensation reaction.

[0037] In another specific embodiment of the present application, step S3 is carried out in the presence of an amine to better promote the efficient hydrolysis condensation reaction, and the amine is preferably aqueous ammonia.

[0038] In another specific embodiment of the present application, the reaction system of step S3 contains organic aluminum and / or aluminum salt, so that the organic aluminum and / or aluminum salt can participate in the hydrolysis and condensation reaction, so that the formed interpenetrating network structure has better density, better water and oxygen barrier properties, and stronger tolerance to high temperature.

[0039] The organic aluminum includes at least one of organic aluminum alcohol and organic aluminum carboxylate, the organic aluminum alcohol includes at least one of aluminum isopropoxide and aluminum sec-butoxide, and the organic aluminum carboxylate includes at least one of basic aluminum acetate, aluminum gluconate, and aluminum tartrate. The aluminum salt includes at least one of aluminum trichloride, aluminum sulfate, aluminum nitrate, aluminum silicate, and aluminum sulfide.

[0040] In another specific embodiment of the present application, step S1 and / or step S2 is performed under an inert atmosphere to better protect the quantum dots from being attacked by water and oxygen.

[0041] The present application also provides an application of the above-mentioned quantum dot complex in the preparation of quantum dot products, wherein the quantum dot complex is added to plastic particles, curing glue or printing ink to make quantum dot products. For example, the quantum dot complex can be prepared into quantum dot glue liquid, quantum dot photoresist or quantum dot ink, and then prepared into quantum dot enhancement film, quantum dot diffusion plate, quantum dot color film, and then prepared into display device.

[0042] In the present application, the initial quantum dots include at least one of a II-VI group compound, a III-V group compound, and a perovskite quantum dot. For example, the II-VI group compound may include: CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgS Te, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, HgZnT eS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe or combinations thereof. The III-V compounds may include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, InZnP, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb or a combination thereof. The perovskite quantum dots include organic perovskite quantum dots and / or inorganic perovskite quantum dots, and the perovskite quantum dots may be related products purchased on the market.

[0043] It can be understood that the structure of the quantum dot body of the present application comes from the initial quantum dot, for example, the structure of the quantum dot body of the present application is the core structure or core-shell structure of the initial quantum dot.

[0044] Some exemplary embodiments according to the present application are described in more detail below; however, the exemplary embodiments of the present application are not limited thereto.

[0045] Example 1

[0046] S1. Preparation of epoxysiloxane-polythiol compound:

[0047] 1 g of pentaerythritol tetrakis (3-mercaptopropionate) and 1 g of 3-glycidyloxypropyltriethoxysilane were dissolved in 10 g of xylene. The system viscosity was 10 cp at this time. The mixture was reacted at 60° C. and nitrogen atmosphere for 24 h to perform a ring-opening reaction to form an epoxysiloxane-thiol compound. The system viscosity was 200 cp at this time.

[0048] S2. Preparation of surface modified quantum dots:

[0049] 12g of xylene solution of epoxysiloxane-thiol compound and 1g of initial quantum dots (green light quantum dots: CdSe / CdSeS / ZnS) were reacted at 90°C in a nitrogen atmosphere, and 10mg of the sample was dissolved in 3ml of PGMEA to form surface-modified quantum dots, wherein the surface-modified organic ligands of the surface-modified quantum dots were derived from epoxysiloxane-polythiol compound;

[0050] S3. Preparation of quantum dot complexes:

[0051] 0.5 ml of ammonia water was added to the surface modified quantum dots and reacted at 60° C. for 1 hour, then the temperature was raised to 120° C. and condensed for 3 hours to make the organic ligands in the surface modified quantum dots react with each other to prepare a quantum dot complex. The quantum dot complex has an interpenetrating network structure. The reaction process is as follows: Figure 1 shown.

[0052] Example 2

[0053] This embodiment is substantially the same as embodiment 1, except that 1 g of 3-glycidyloxypropyltriethoxysilane in step S1 is adjusted to 0.57 g of 3-glycidyloxypropyltriethoxysilane, the reaction temperature in step S1 is 20° C., and the viscosities of the system before and after the reaction are 10 cp and 128 cp, respectively.

[0054] Example 3

[0055] This embodiment is substantially the same as embodiment 1, except that 1 g of 3-glycidyloxypropyltriethoxysilane in step S1 is adjusted to 1.11 g of 3-glycidyloxypropyltriethoxysilane, the reaction temperature is adjusted to 40° C., and the viscosities of the system before and after the reaction are 15 cp and 356 cp, respectively.

[0056] Example 4

[0057] This embodiment is substantially the same as embodiment 1, except that 1 g of 3-glycidyloxypropyltriethoxysilane in step S1 is adjusted to 1.67 g of 3-glycidyloxypropyltriethoxysilane, and the viscosities of the system before and after the reaction are 18 cp and 800 cp, respectively.

[0058] Example 5

[0059] This embodiment is substantially the same as embodiment 1, except that 1 g of pentaerythritol tetrakis(3-mercaptopropionate) in step S1 is adjusted to 1.9 g of tris[2-(3-mercaptopropionyloxy)ethyl]isocyanurate, the temperature is adjusted to 40° C., and the viscosities of the system before and after the reaction are 19 cp and 234 cp, respectively.

[0060] Example 6

[0061] This embodiment is substantially the same as embodiment 1, except that 1 g of pentaerythritol tetrakis(3-mercaptopropionate) in step S1 is adjusted to 0.95 g of tris[2-(3-mercaptopropionyloxy)ethyl]isocyanurate, and the viscosities of the system before and after the reaction are 24 cp and 513 cp, respectively.

[0062] Example 7

[0063] This example is substantially the same as Example 1, except that 1 g of pentaerythritol tetrakis(3-mercaptopropionate) in step S1 is adjusted to 0.54 g of 1,6-hexanedithiol, and the viscosity of the system before and after the reaction is 9 cp and 89 cp, respectively.

[0064] Example 8

[0065] This embodiment is substantially the same as embodiment 1, except that 1 g of 3-glycidyloxypropyltriethoxysilane in step S1 is adjusted to 0.74 g of 1,3-bis(3-glycidyloxypropyl)-1,1,3,3-tetramethyldisiloxane, and the viscosities of the system before and after the reaction are 15 cp and 213 cp, respectively.

[0066] Example 9

[0067] This embodiment is substantially the same as Embodiment 1, except that: 1 g of pentaerythritol tetrakis (3-mercaptopropionate) in step S1 is adjusted to 1 g of 1,6-hexanedithiol, and 1 g of 3-glycidyloxypropyltriethoxysilane is adjusted to 2.42 g of 1,3-bis (3-glycidyloxypropyl) -1,1,3,3-tetramethyldisiloxane, and the viscosities of the system before and after the reaction are 14 cp and 278 cp, respectively.

[0068] Example 10

[0069] This embodiment is substantially the same as Embodiment 1, except that: 1 g of pentaerythritol tetrakis (3-mercaptopropionate) in step S1 is adjusted to 1 g of tris [2- (3-mercaptopropionyloxy) ethyl] isocyanurate, and 1 g of 3-glycidyloxypropyl triethoxysilane is adjusted to 1.38 g of 1,3-bis (3-glycidyloxypropyl) -1,1,3,3-tetramethyldisiloxane, and the viscosities of the system before and after the reaction are 14 cp and 278 cp, respectively.

[0070] Embodiment 11

[0071] This embodiment is substantially the same as Embodiment 1, except that in step S3, 3 g of aluminum isopropoxide is added to the surface-modified quantum dots before the temperature is raised to 120°C.

[0072] Example 12

[0073] This embodiment is substantially the same as Embodiment 1, except that in step S3, 20 g of aluminum isopropoxide is added to the surface-modified quantum dots before the temperature is raised to 120°C.

[0074] Embodiment 13

[0075] This embodiment is substantially the same as Embodiment 1, except that the initial quantum dots in step S2 are replaced with red light quantum dots: InP / ZnS.

[0076] Embodiment 14

[0077] This embodiment is substantially the same as embodiment 1, except that the initial quantum dots in step S2 are replaced with red light perovskite quantum dots: CsPbBr 3 .

[0078] Comparative Example 1

[0079] This comparative example is substantially the same as Example 1, except that 1 g of 3-glycidyloxypropyltriethoxysilane in step S1 is adjusted to 0.5 g of tetrapropoxysilane, and the viscosities of the system before and after the reaction are 45 cp and 67 cp, respectively.

[0080] Comparative Example 2

[0081] This comparative example is substantially the same as Example 15, except that 1 g of tris[2-(3-mercaptopropionyloxy)ethyl]isocyanurate in step S1 is adjusted to 0.73 g of dodecanethiol, and the viscosities of the system before and after the reaction are 87 cp and 118 cp, respectively.

[0082] Comparative Example 3

[0083] This comparative example is substantially the same as Example 16, except that 1 g of tris[2-(3-mercaptopropionyloxy)ethyl]isocyanurate in step S1 is removed, and the viscosity of the system before and after the reaction is 56 cp and 62 cp, respectively.

[0084] The original QD (green light quantum dot) and 800 mg of quantum dot powder in Examples 1 to 12 and Comparative Examples 1 to 3 were mixed with 20 g of polymethyl methacrylate, and a quantum dot film was prepared by co-extrusion in an extruder using a stepwise heating method from 185° C. to 200° C. The aging data of the quantum dot film was tested under two aging conditions. The aging conditions were: a temperature of 60° C., a humidity of 90%, and a power of 40 W / m 2 The test results are shown in Table 1. Test backlight: brightness is 1000nits, and the emission peak wavelength is at 447nm.

[0085] Table 1 Data of quantum dot film under aging conditions

[0086]

[0087]

[0088]

[0089] It can be seen from Table 1 that compared with the initial quantum dots and the quantum dot films prepared by the quantum dots of Comparative Examples 1 to 3, the quantum dot films prepared by the quantum dot composites of Examples 1 to 14 of the present application have strong anti-aging ability, high brightness and EQE maintenance rate, indicating that the quantum dot composites prepared by the technical scheme of the present application have good stability, and the quantum dot films prepared therefrom have high stability, which is conducive to promoting the commercial application of optical components containing quantum dots.

[0090] Although the inventors have elaborated and enumerated the technical solutions of the present application in detail, it should be understood that it is obvious for those skilled in the art to modify and / or adapt the above embodiments or adopt equivalent alternative solutions, which cannot deviate from the essence of the spirit of the present application. The terms appearing in the present application are used to explain and understand the technical solutions of the present application and cannot constitute limitations on the present application.

Claims

1. A quantum dot composite, characterized in that: It includes a quantum dot body and an interpenetrating network structure coated and connected to the quantum dot body, wherein the interpenetrating network structure is formed by hydrolysis and condensation of the organic ligands of a plurality of surface-modified quantum dots; the surface-modified quantum dots include a quantum dot body and an organic ligand modified on the surface of the quantum dot body, wherein the organic ligand is derived from an epoxysiloxane-polythiol compound, wherein the organic ligand contains at least one thiol terminal group and a plurality of siloxane terminal groups, and the epoxysiloxane-polythiol compound is obtained by the reaction of polythiol and epoxysiloxane.

2. The quantum dot composite according to claim 1, characterized in that The polythiol is at least one of pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate), tris [2- (3-mercaptopropionyloxy) ethyl] isocyanurate, 1,6-hexanedithiol, 2,3-dimercapto-1-propanol, propane-1,2,3-trithiol, 2-mercaptoethyl ether, 1,8-octanedithiol, 1,8-dimercapto-3,6-dithiaoctane and trithiocyanic acid.

3. The quantum dot composite according to claim 1, characterized in that The molar ratio of the polythiol to the epoxysiloxane is 1:(0.5-4).

4. A method for preparing a quantum dot complex, characterized in that: Includes steps: S1. At 20-60° C., a polythiol and an epoxysiloxane are subjected to a ring-opening reaction to form an epoxysiloxane-polythiol compound; S2, reacting the epoxysiloxane-polythiol compound with the initial quantum dots at 60-120° C. to form surface-modified quantum dots, wherein the surface of the surface-modified quantum dots is modified with an organic ligand, and the organic ligand is derived from the epoxysiloxane-polythiol compound; S3. At 60-140° C., the organic ligands in the surface-modified quantum dots undergo a hydrolysis-condensation reaction to form a quantum dot complex having an interpenetrating network structure.

5. The method for preparing the quantum dot composite according to claim 4, characterized in that: The mass ratio of the epoxysiloxane-polythiol compound to the initial quantum dots is (0.1-20):

1.

6. The method for preparing the quantum dot composite according to claim 4, characterized in that: In the step S3, the reaction is carried out in the presence of an amine.

7. The method for preparing a quantum dot composite according to claim 4, characterized in that: The reaction system in step S3 contains organic aluminum and / or aluminum salt.

8. The method for preparing a quantum dot composite according to claim 4, characterized in that: The step S1 and / or step S2 is performed under an inert atmosphere.

9. A quantum dot product, characterized in that: It comprises the quantum dot complex as described in any one of claims 1 to 3 or the quantum dot complex prepared by the method according to any one of claims 4 to 8.

Images