Continuous treatment method and device and preparation method of quantum dots

Abstract

The invention relates to a continuous treatment method and device and a preparation method of quantum dots. The continuous treatment method comprises the steps of purification, particle size grading and cleaning, specifically, a gel medium used for particle size grading is cleaned; the purification step comprises the following steps: a contact step: enabling the quantum dot system to be treated to be in contact with the stationary phase; in the extraction step, an extraction agent is used for eluting non-target components in the quantum dot system to be treated, the non-target components comprise one or more of unreacted components, impurity components and free ligand components, and in the extraction step, the target components are substantially reserved in a stationary phase; an elution step in which an eluent is used to elute the target component from the stationary phase; a regeneration step, wherein the regeneration step comprises cleaning the stationary phase by using a cleaning agent; in the purification step, one or more times of circulation formed by the steps or the steps are carried out to continuously carry out the purification step, and the target component comprises purified quantum dots.

Description

Technical Field

[0001] The invention belongs to the field of materials and relates to a method for processing nano materials, in particular to a continuous processing method and device and a method for preparing quantum dots. Background Art

[0002] The synthesis of quantum dot materials can be completed in organic media and aqueous media. Among them, the organic phase synthesis can obtain quantum dot materials with high crystal quality by screening high boiling point organic solvents, precursors and ligands and / or surfactants. In addition, the organic solvent can also be combined with the precursor material as a ligand to prevent the agglomeration of nanomaterials. During the aqueous phase synthesis, the precursor is combined into a nano quantum dot material in the presence of a surfactant (such as mercaptopropionic acid, etc.).

[0003] Furthermore, by synthesizing quantum dot materials in an organic medium or an aqueous medium, a purification step is usually required to obtain the final product. During the purification process, impurities, solvents, unreacted precursors or excess ligands can be removed by purification. On the one hand, the composition of the purified system is relatively complex, and on the other hand, the result of purification will have a significant impact on the quality of the quantum dot product. Therefore, the purification step is also very important for quantum dot materials, especially for colloidal quantum dot materials.

[0004] Quantum dot purification technology is a method of purifying quantum dot stock solution after synthesis to remove impurities and excess ligands, thereby improving the purity and optical properties of quantum dots. Traditional purification methods, including precipitant precipitation filtration, solvent extraction, membrane filtration, electrophoretic separation, and chromatographic separation, usually need to be combined according to actual needs to achieve the best purification effect.

[0005] Reference 1 discloses a method for preparing a rare earth colloidal quantum dot material, wherein after heating a quantum dot precursor mixture to grow crystals, the quantum dots are precipitated by adding ethanol or acetone solution, and then the final purified quantum dots are obtained by centrifugal separation. Reference 2 discloses a method for preparing lead sulfide colloidal quantum dots, wherein after obtaining a lead sulfide colloidal quantum dot stock solution, impurities are removed by centrifugal treatment. Reference 3 adds a certain amount of precipitant to a system to be purified containing quantum dots, mixes, precipitates the quantum dots, separates the quantum dots from the system to be purified, and obtains powdered quantum dots. Reference 4 discloses a method for purifying quantum dots and a device for purifying quantum dots, which removes impurities such as oil-soluble ligands in the quantum dot stock solution through an ultrafiltration membrane. Similar to Reference 4, Reference 5 removes long-chain ligand substances on quantum dots by designing an ultrafiltration membrane. Reference 6 discloses a method for purifying quantum dots, wherein the quantum dot solution is adjusted to be alkaline, DNA is added to the alkaline quantum dot solution and mixed, and further a gel electrophoresis method is used to obtain quantum dots coated with DNA on the surface. Reference 7 uses molecular sieves to separate the required graphene quantum dot materials through adsorption and desorption.

[0006] In addition, it is known that solid phase extraction (SPE) is a sample pretreatment technology that has been developed since the mid-1980s. It is developed by combining liquid-solid extraction and liquid chromatography technology. It is mainly used for the pretreatment of liquid chromatography samples to separate, purify and enrich target detection objects. SPE technology is based on the theory of liquid-solid chromatography and uses selective adsorption and selective elution to enrich, separate and purify samples. It is a physical extraction process that includes liquid and solid phases; it can also be roughly regarded as a simple chromatographic process.

[0007] There are not many reports on the direct treatment of quantum dot reaction systems using solid phase extraction technology. Reference 8 describes a simple and universal carbon dot purification procedure. After the hydrothermal heating process, the reaction mixture usually contains unreacted starting materials and by-products as well as carbon dots. The purification method is based on solid phase extraction technology, in which the reaction mixture is adsorbed on porous alumina, and the carbon dots are separated from the by-products and unreacted organic matter using an appropriate solvent, and finally the carbon dots are recovered from the alumina using a simple method. In addition, there are also reports on the use of chromatography technology to separate and detect quantum dot materials of different particle sizes (reference 9).

[0008] In addition, for the particle size classification of quantum dot materials, attempts have been made to use electric fields for electrophoresis or electrodeposition, which seems to be a more effective method, especially considering the sensitivity of quantum dot materials of different charges and sizes to the electric field potential. Reference 10 discloses a method for purifying quantum dots, by adjusting the quantum dot solution to be alkaline, adding DNA to the alkaline quantum dot solution and mixing, and further obtaining quantum dots with DNA coated on the surface by gel electrophoresis. Reference 11 provides a purification device, purification method and purification system for a nanocrystal solution, which purifies quantum dot materials by electric fields and membrane filters. In addition, there are also reports of attempts to use gel chromatography to classify quantum dots by particle size, such as reference 12.

[0009] Although the above-mentioned prior art has conducted a certain degree of research on the purification or particle size classification methods of quantum dot materials, it is still not sufficient to provide a continuous, efficient, and online direct purification and classification method for quantum dot stock solution (reaction product system).

[0010] References:

[0011] Reference 1: CN106340592A

[0012] Reference 2: CN111635759A

[0013] Reference 3: CN108219792A

[0014] Reference 4: CN106474932A

[0015] Reference 5: CN111375312A

[0016] Reference 6: CN110938422A

[0017] Reference 7: CN104777081A

[0018] Reference 8: Apostolos, K., et al. (2018) Solid Phase Extraction for the Purification of Violet, Blue, Green and Yellow Emitting Carbon Dots.

[0019] Nanoscale, 24, 11293-11296.

[0020] Cited literature 9: Hinterberger, V., et al. (2019) Purification and Structural Elucidation of Carbon Dots by Column Chromatography. Nanoscale, 11, 8464-8474.

[0021] Reference 10: CN110938422A

[0022] Reference 11: CN106823814A

[0023] Reference 12: Study on the Purification and Fluorescence Properties of Carbon Quantum Dots by Gel Penetrate Chromatography, Ting Jiang et al, Advances in Analytical Chemistry, 2018, 8(3), 103-111 Summary of the invention

[0024] Problem that the invention aims to solve

[0025] As mentioned above, on the one hand, the solid phase extraction technology in the prior art is usually used for pre-treatment of liquid chromatography, but not directly for direct purification of quantum dot reaction stock solution. On the other hand, for example, Reference 8 and Reference 9, although both use stationary phases in the so-called "purification", in fact, their stationary phases mainly play the role of separating quantum dots of different diameters (particle size classification of size exclusion chromatography), rather than directly obtaining purified quantum dot materials through solid phase extraction. For example, Reference 8 extracts quantum dots of different particle sizes (different optical properties) from the stationary phase by combining different solvents, but still requires subsequent washing and filtration to obtain the final product. Its purification and classification process is not suitable for large-scale and efficient production.

[0026] In addition, the above-mentioned classification and purification methods are not efficient. Especially when the current purification technology is scaled up, batch purification requires more manual operations, and the cost of semi-automatic or fully automatic purification is quite high. Moreover, these conventional technical methods have great limitations in continuous repetitive production, and it is difficult to couple to the downstream of the automated synthesis of quantum dots. In particular, considering that the regeneration of the stationary phase / extraction column and the purification efficiency are mutually restricted, the online continuous purification process itself has not been applied on a large scale.

[0027] Furthermore, although references 10 and 11 use methods such as electric fields for purification or particle size classification, this method has certain requirements on the type of quantum dots, especially the surface properties. Or, if the particle size classification is to be precisely controlled, it is necessary to precisely control the potential distribution or use a filter membrane as an auxiliary, which is difficult in terms of operation and therefore reduces the feasibility of large-scale application.

[0028] Regarding reference 12, gel chromatography was used to fractionate the carbon dots by size, but it was not possible to directly and continuously process the carbon quantum dot synthesis reaction products.

[0029] Therefore, based on the above-mentioned problems existing in the prior art, the present invention primarily provides a method that can be directly used to process a quantum dot synthesis reaction product system. The method is a continuous, efficient, and online processing method. Moreover, through the adjustment of different elution steps, the final quantum dot material obtained by the method of the present invention can have good purity even without further cooperation with other purification methods. The purified quantum dot material can be further directly subjected to particle size classification with the aid of gel chromatography.

[0030] In addition, another object of the present invention is to provide a device or system for online continuous processing, which can directly process the quantum dot synthesis reaction product system in an efficient and high-purity manner by executing the above-mentioned method, and obtain purified and well-graded quantum dot materials, which can meet the needs of large-scale production and can be reused.

[0031] In addition, another object of the present invention is to provide a method for preparing quantum dots, which can continuously and efficiently prepare quantum dot materials and can screen the particle size of quantum dots online.

[0032] Solutions for solving problems

[0033] [1] The present invention primarily provides a continuous processing method, which is a continuous processing method for quantum dot materials, wherein the method comprises the following steps:

[0034] A purification step, purifying the quantum dot system to be treated to obtain purified quantum dots, and

[0035] a step of particle size classification, wherein the purified quantum dots are subjected to particle size classification using gel chromatography;

[0036] A cleaning step for cleaning the gel medium used for particle size classification;

[0037] Wherein, the purification step comprises:

[0038] A contacting step, so that the quantum dot system to be treated contacts with the stationary phase;

[0039] An extraction step, using an extractant to elute non-target components in the quantum dot system to be treated, wherein the non-target components include one or more of unreacted components, impurity components, and free ligand components, and the target components are substantially retained in the stationary phase during the extraction step;

[0040] an elution step, using an eluent to elute the target component from the stationary phase;

[0041] a regeneration step, wherein the regeneration step comprises using a cleaning agent to clean the stationary phase,

[0042] In the purification step, the above steps or the cycles formed by the steps (i.e., purification cycles) are performed once or multiple times to continuously perform the purification steps.

[0043] And, the target component includes the purified quantum dots.

[0044] [2] The treatment method according to [1], wherein the quantum dot system to be treated is an untreated reaction product system directly obtained from a quantum dot material synthesis reaction; and the regeneration step also includes a step of drying the cleaned stationary phase.

[0045] [3]. The treatment method according to [1] or [2], wherein the quantum dot system to be treated is an oily quantum dot system or an aqueous quantum dot system.

[0046] [4] The treatment method according to any one of [1] to [3], wherein the stationary phase is composed of particles, and the surface of the particles is modified by silane having a long-chain alkyl group.

[0047] [5] A treatment method according to any one of [1] to [4], wherein in the purification step, a cycle formed by the above steps is performed one or more times, and after the cycle starts, while the regeneration step is being performed, at least one of the contacting step, the extraction step, and the elution step is being performed.

[0048] [6] The treatment method according to any one of [1] to [5], wherein in the extraction step, the non-target components are eluted by the solvation of the extractant, and / or in the extraction step, one or more of the following conditions are adjusted to elute the non-target components:

[0049] i. Polarity of the extractant

[0050] ii. Solubility of the extractant

[0051] iii. Flow rate of the extractant

[0052] iv. Working time of the extractant

[0053] v. Extraction temperature.

[0054] [7] The treatment method according to any one of [1] to [6], wherein in the elution step, one or more eluents are used to elute the target component through the solvation effect of the eluents; and / or, in the second elution step, one or more of the following conditions are adjusted to elute the target component:

[0055] i. Polarity of the eluent

[0056] ii. Solubility of the eluent

[0057] iii. Eluent flow rate

[0058] iv. Working time of the eluent

[0059] v. Elution temperature.

[0060] [8] A processing method according to any one of [1] to [7], wherein the target component including the purified quantum dots is directly processed using gel chromatography, and optionally, the gel chromatography includes processing using a porous gel material.

[0061] [9] Furthermore, the present invention also provides a device for use in the processing method described in any one of [1] to [8] above, wherein the device comprises:

[0062] Purification system and grading system,

[0063] Wherein, the purification system comprises:

[0064] Injection unit, solid phase extraction unit and sample recovery unit,

[0065] The sample injection unit is used to place the quantum dot system to be processed.

[0066] The solid phase extraction unit comprises a mobile phase providing unit, a stationary phase unit and optionally a solvent / waste liquid collecting unit;

[0067] The grading system includes:

[0068] A gel chromatography unit connected in series with the stationary phase unit, wherein the mobile phase required by the gel chromatography unit of the fractionation system is provided via the mobile phase providing unit in the purification system or via an additional mobile phase providing unit different therefrom.

[0069]

[10] . In addition, the present invention also provides a method for preparing quantum dots, the method comprising:

[0070] Steps for synthesizing quantum dot materials;

[0071] Successive processing steps of quantum dot materials,

[0072] The step of continuously treating the quantum dot material comprises treating the reaction product system obtained by the step of synthesizing the quantum dot material using the continuous treatment method described in any one of [1] to [8].

[0073] Effects of the Invention

[0074] By implementing the above technical solution, the present invention can achieve the following technical effects:

[0075] 1) The method of the present invention is a continuous method for processing quantum dot materials, which can directly purify and grade the reaction product system obtained from the quantum dot synthesis step that has not been processed in other steps, and can be processed online and continuously to obtain high-purity quantum dot materials.

[0076] 2) The method and apparatus of the present invention can provide a continuous, online, efficient processing method through multiple purification cycles, thereby increasing the scale of the purification process, and directly coupling the purification of quantum dots with particle size classification, thereby providing large-scale, efficient purification and particle size classification processing directly for the quantum dot product system.

[0077] 3) The method and device of the present invention have good scalability and compatibility, and can be further coupled with other subsequent processing methods and devices of quantum dots, providing more flexibility in the processing of quantum dot materials.

[0078] 4) In some preferred embodiments, by adjusting the stationary phase characteristics (such as particle size, etc.), the retention characteristics and regeneration capacity are balanced, making continuous purification possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 It is a schematic diagram of the online solid phase extraction purification system of the present invention (only one solid phase extraction column is shown).

[0080] Figure 2 Microscope morphology of the quantum dot film before and after purification. DETAILED DESCRIPTION

[0081] The following is a detailed description of the present invention. The following description of the technical features is based on representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. It should be noted that:

[0082] In this specification, the numerical range expressed using "a numerical value A to a numerical value B" means a range including the endpoints numerical values ​​A and B.

[0083] In the present specification, the use of “substantially” or “essentially” means that the standard deviation from a theoretical model or theoretical data is within a range of 3%, preferably 2%, and more preferably 1%.

[0084] In this specification, unless otherwise specified, "%" means mass percentage.

[0085] In this specification, "room temperature" is used to refer to a temperature range of 23±2°C.

[0086] In this specification, the word "may" means both performing a certain process and not performing a certain process.

[0087] In this specification, the term "plurality" refers to a number of 2 or more.

[0088] In this specification, the "boiling point" refers to the boiling point under normal pressure.

[0089] In this specification, the term "classification" refers to classification in terms of particle size or size unless otherwise specified.

[0090] In this specification, unless otherwise specified, "quantum dot" and "quantum dot material" have equivalent physical and chemical meanings.

[0091] In the present specification, "optional" or "optionally" means that the event or situation described below may or may not occur, and the description includes cases where the event occurs and cases where it does not occur.

[0092] In this specification, the references to "some specific / preferred embodiments", "other specific / preferred embodiments", "embodiments", etc., mean that the specific elements (e.g., features, structures, properties and / or characteristics) described in connection with the embodiments are included in at least one embodiment described herein, and may or may not exist in other embodiments. In addition, it should be understood that the elements may be combined in various embodiments in any suitable manner.

[0093] The present invention primarily provides a new strategy for the purification and particle size classification of quantum dot materials based on solid phase extraction-gel chromatography. Specifically, it relates to a method and apparatus for continuous and efficient purification treatment and gel chromatography particle size classification based on solid phase extraction technology. The treatment method and apparatus of the present invention are particularly suitable for directly purifying the reaction product system obtained by synthesizing quantum dot materials. Furthermore, multiple purification cycles can be performed, and the purified quantum dots obtained in each purification cycle can be directly subjected to particle size classification by gel chromatography. Therefore, the treatment method of the present invention can achieve online, large-scale continuous purification and classification of quantum dot materials.

[0094] <First aspect>

[0095] In a first aspect of the present invention, a method for processing quantum dot materials is provided, in particular, a method for continuously purifying quantum dot materials and classifying their particle sizes. The method of the present invention mainly comprises the following steps:

[0096] A purification step, purifying the quantum dot system to be treated to obtain purified quantum dots; and

[0097] The step of particle size classification is to classify the purified quantum dots by gel chromatography.

[0098] A cleaning step for cleaning the gel medium used for particle size classification;

[0099] Wherein, the purification step comprises:

[0100] A contacting step, so that the quantum dot system to be treated contacts with the stationary phase;

[0101] An extraction step, using an extractant to elute non-target components in the quantum dot system to be treated, wherein the non-target components include one or more of unreacted components, impurity components, and free ligand components, and the target components are substantially retained in the stationary phase during the extraction step;

[0102] an elution step, using an eluent to elute the target component from the stationary phase;

[0103] a regeneration step, wherein the regeneration step comprises using a cleaning agent to clean the stationary phase,

[0104] In the purification step, the above steps or cycles formed by the steps (i.e., purification cycles) are performed once or multiple times to continuously perform the purification steps.

[0105] In some specific embodiments, in the purification step, one or more cycles formed by the above steps are performed, and after the cycle starts, while the regeneration step is being performed, at least one of the contacting step, the extraction step, and the elution step is being performed.

[0106] And, the target component includes the purified quantum dots.

[0107] Furthermore, in principle, there is no particular limitation on the temperature at which the above steps are performed. The steps may be performed at room temperature, or the relevant elements or devices may be heated whenever necessary.

[0108] (Quantum dot system to be processed)

[0109] In principle, there is no particular limitation on the quantum dot system to be processed in the present invention, and the system may include any non-target components in addition to the target quantum dot material. These non-target components may include one or more of: unreacted raw material components, solvents, excess or free ligand components, and other impurity components (e.g., byproducts during quantum dot synthesis).

[0110] Further, in some specific embodiments, the quantum dot system to be treated in the present invention can be a reaction product system directly obtained by the synthesis reaction of the synthetic quantum dot material, and the "directly" here means that after the reaction, no other steps that may cause changes in the system composition are performed. Such a reaction product system may also be referred to as a "quantum dot stock solution" in some occasions.

[0111] For the above-mentioned reaction product system of the present invention, after the quantum dot synthesis reaction is completed, the reaction mixture can usually be cooled to room temperature or other processing temperature for subsequent purification and particle size classification.

[0112] In principle, the present invention has no particular limitation on the synthesis method of quantum dots, for example, methods for preparing quantum dot materials from II-VI, IV-VI or III-V semiconductor elements may be used.

[0113] In some specific embodiments of the present invention, the synthesis method of the quantum dot material includes a method for synthesizing II-VI semiconductor quantum dot materials such as cadmium sulfide (CdS), cadmium tin (CdSe), cadmium telluride (CdTe) and zinc sulfide (Zns); a method for synthesizing IV-VI semiconductor quantum dot materials such as lead sulfide (PbS) and lead selenide (PbSe); a method for synthesizing III-V semiconductor quantum dot materials such as indium phosphide (InP) and indium arsenide (InAs); a method for synthesizing a core-shell structure Quantum dot materials such as CdS / ZnS, CdSe / CdS, CdSe / ZnS, CdSe / CdS / ZnS, CdTe / CdS, CdTe / CdS / ZnS, ZnSe / ZnS, InP / ZnSe, InP / ZnS, InP / ZnSe / ZnS, InP / GaP / ZnS; methods for synthesizing carbon quantum dot materials, noble metal single substances such as Au, Ag and other quantum dot materials, and methods for synthesizing quantum dot materials based on perovskite structure. These methods can be methods based on organic media (oily quantum dot materials) or methods based on aqueous media (aqueous quantum dot materials). For such methods, more specifically, hot injection methods or microfluidic methods can be included.

[0114] In some preferred embodiments of the present invention, the synthesis method applicable to the present invention can be selected from those synthesis methods for forming (semiconductor) oily colloidal quantum dot materials; in some other preferred embodiments, the synthesis method applicable to the present invention can be selected from those quantum dot synthesis methods based on hot injection or microfluidic synthesis.

[0115] Furthermore, in the synthesis method of quantum dot materials based on organic media, the following can be cited: first, the raw materials are dissolved in an organic solvent or a ligand to form a precursor, and then they are mixed under heating conditions to form the quantum dot material through a chemical reaction.

[0116] Regarding the above-mentioned organic solvents or ligands, it should be noted that, when preparing the precursor, the organic solvent itself can also be a ligand. Therefore, in some specific embodiments, the organic solvent can generally be divided into a ligand organic solvent and a non-ligand organic solvent.

[0117] In some specific embodiments of the present invention, the ligand or ligand-containing organic solvent usually has a relatively high boiling point (preferably, for example, a boiling point above 300° C.), dissolving the raw materials to form a quantum dot precursor. For the ligand or ligand-containing organic solvent, common ones include some polar organic solvents with long-chain alkyl groups, including acid compounds, amine compounds, thiol compounds, and phosphorus-containing compounds with long-chain alkyl groups. Specifically, oleylamine, dodecyl mercaptan, oleic acid, dioctyl ether, trioctyl phosphine oxide (TOPO), trioctyl phosphine (TOP), hexylphosphonic acid (HPA), tetradecylphosphonic acid (TDPA), etc. and mixtures thereof can be cited.

[0118] For non-ligand organic solvents, they can generally be octadecene, diphenyl ether, paraffin oil, methyl pyrrolidone, etc. In addition, it is related to the required reaction temperature. When the reaction temperature allows, the non-ligand organic solvent can also be a low boiling point solvent such as ethanol and toluene. For the use of non-ligand organic solvents, after using ligands or ligand organic solvents to dissolve raw materials to obtain quantum dot precursors, the precursors can be dissolved or dispersed in these solvents.

[0119] There is no particular limitation on the reaction method. After preparing precursors with the aid of ligands or ligand-containing organic solvents, two or more precursors may be simultaneously injected into another organic solvent to carry out the growth reaction of quantum crystals under heating conditions. Alternatively, one ligand may be injected into another ligand solution to carry out the growth reaction of quantum crystals under heating conditions.

[0120] The above raw materials are mainly the sources of various elements in quantum dots. These raw materials can be one or more of their simple substances, oxides, salt compounds, organic compounds, etc. For example, in some specific embodiments, when synthesizing AxBy type quantum dots (wherein A can be Cd, Hg, Pb, Zn, Ag, Cu, Mn, Sn, Ni, Bi or Eu, etc.; B can be S, Se or Te), the oxide, salt compound or organic compound of A can be dissolved in a ligand or a ligand organic solvent to obtain a precursor, and in addition, the simple substance of B is dissolved in an organic solvent to form another precursor, and then the two precursors are mixed in a heated state to prepare quantum dots.

[0121] In addition, the present invention has no particular limitation on the temperature conditions for preparing quantum dots. For example, in the hot injection method, the reaction temperature can usually be controlled within the range of 180 to 380° C. as required.

[0122] The present invention is not particularly limited to the above-mentioned synthesis method based on aqueous media, and the raw materials can be dissolved in water and hydrothermally synthesized in the presence of a surfactant. Such a surfactant can be a compound having a bipolar head, typically an alkyl acid compound having a thiol group, etc.

[0123] The quantum dot stock solution obtained by the above-mentioned synthesis reaction usually contains organic solvents, unreacted raw materials (precursors), excess free ligands and other impurities (such as by-products, etc.) in addition to the target quantum dot crystals. Substances other than quantum dots need to be removed through subsequent purification treatment.

[0124] There is no particular limitation on the morphology of the quantum dot crystals in the above stock solution, for example, they may have a spherical or substantially spherical structure, a rod-like structure, a sheet-like structure, a cone-like structure, a tower-like structure, a polygonal structure, a cubic structure, etc. In some preferred embodiments of the present invention, the obtained quantum dot crystals have a spherical or substantially spherical morphology; in other preferred embodiments, the obtained quantum dot crystals have a (spherical or substantially spherical) core-shell structure.

[0125] There is no particular restriction on the particle size of the target quantum dot crystal material. In some specific embodiments of the present invention, the quantum dot stock solution may include quantum dot crystal material with a particle size of 1 to 70 nm. Preferably, the particle size range may be 2 to 60 nm, more preferably 3 to 50 nm, and further preferably 4 to 40 nm.

[0126] In addition, there is no particular limitation on the apparatus used for synthesizing quantum dot materials, and in some preferred embodiments, such an apparatus has stirring and / or inert gas supply components.

[0127] In some preferred embodiments of the present invention, the quantum dot system to be processed in the present invention may be an oily quantum dot system containing colloidal quantum dots, especially containing semiconductor colloidal quantum dots.

[0128] (Purification Step)

[0129] The purification step of the present invention mainly involves purifying the synthesized quantum dot stock solution to obtain target components including purified quantum dots.

[0130] The purification step includes: a contacting step, an extracting step, an eluting step, and a (stationary phase) regeneration step. In addition, in the purification step, each of the above steps or a cycle formed by each of the steps (i.e., a purification cycle) may be performed once or multiple times to continuously perform the purification step.

[0131] Steps to contact

[0132] In the contacting step of the present invention, the quantum dot system to be processed is mainly contacted with the stationary phase so that the stationary phase adsorbs, especially completely adsorbs the quantum dot system. In some specific embodiments, the additional solvent provided in the mobile phase providing unit described below can be used as a carrier to transport the quantum dot system to be processed to the stationary phase.

[0133] For the stationary phase in the present invention, it can be an organic or inorganic substance with a porous surface structure. In some preferred embodiments, from the perspective of convenient stationary phase regeneration, preferably, a porous inorganic substance is used as the stationary phase. For such a stationary phase, in some specific embodiments of the present invention, it can be a metal or semi-metal oxygen-containing system. Preferably, it can be a silicon oxygen-containing system. For such a stationary phase, various forms of silicon dioxide can be listed, such as silica gel, glass (fused silica), etc.

[0134] The stationary phase of the present invention can be used in a granular form, that is, the stationary phase is preferably composed of particles, and such particles can be substantially spherical particles. From the perspective of solid phase extraction effect, the particle size of such particles can be less than 1000 μm, preferably less than 800 μm, more preferably less than 600 μm, and more preferably less than 400 μm. If the particle size is too high, the pores between the packed particles are too large. In addition, from the perspective of smooth flow of the mobile phase and prevention of leakage, the particle size of the particles can be greater than 100 μm.

[0135] Furthermore, from the perspective of effective retention of the quantum dot material, the pore size of the surface openings of the above-mentioned stationary phase is less than 700 angstroms, preferably less than 500 angstroms, and more preferably less than 400 angstroms. In principle, there is no particular restriction on the lower limit of the pore size, and for example, it can be greater than 10 angstroms, preferably greater than 20 angstroms, and more preferably greater than 30 angstroms.

[0136] In addition, from the perspective of adsorption, preferably, the surface of the above-mentioned stationary phase can be further modified. The method of modification can be adjusted according to the different objects to be treated. For example, in some specific embodiments, when a reverse phase stationary phase is required, a non-polar, hydrophobic stationary phase can be obtained by modifying the surface of the stationary phase with an alkyl group or the like.

[0137] For such silane, a long-chain alkyl group is preferred, for example, one or more alkyl groups having carbon atoms of 12 to 32. Specific examples thereof include octadecyltrimethoxysilane and the like.

[0138] The above-mentioned stationary phase of the present invention is mainly set to take into account the realization of the following performances:

[0139] For the stationary phase, its adsorption selectivity and the difficulty of desorption usually show opposite trends, that is, in the solid phase extraction process, the better the selective retention effect of the stationary phase on the target component, the more difficult it is to desorb the target component during desorption. Of course, this does not always cause great trouble for discontinuous operation, because for such discontinuous operation, there is a higher degree of freedom in the control time, but this still affects the operating efficiency. For continuous operation, for example, after the operation cycle described in the present invention is turned on, before the next contact step begins, at least one regenerated stationary phase must be prepared, so this requires that the balance between the selective retention and desorption of the stationary phase should be regulated. It has been found that in the present invention, when the particle size of the stationary phase particles is preferably controlled at 105μm to 250μm (for example, 110μm, 130μm, 150μm, 170μm, 190μm, 200μm, 210μm, 230μm, etc.) (especially when the pore size of the opening on the surface of the particle is 10 to 700 angstroms), the above balance can be better achieved. Through this particle characteristic, not only can the appropriate specific surface area be retained, but also the appropriate spacing / gaps between particles can be maintained, so that good retention selectivity can be achieved, and better efficiency can be achieved during desorption. This allows the stationary phase to be regenerated and immediately enter the next cycle of contact steps. This greatly improves the efficiency for large-scale continuous online purification of quantum dots.

[0140] Through experiments, it was found that the number of quantum dots adsorbed by the stationary phase with a particle size of 200 μm was 166, the number of quantum dots adsorbed by the stationary phase with a particle size of 750 μm was 55, and the number of quantum dots adsorbed by the stationary phase with a particle size of 350 μm was about 70. The particle size of the stationary phase provided by the present application is smaller, and the surface is etched, so its specific surface area is greatly increased, and the final adsorption amount is also greatly increased.

[0141] For the use of the stationary phase of the present invention, typically, the stationary phase can be filled into a tube to form a columnar stationary phase. For such a tube, from the perspective of ease of operation, the inner diameter is preferably 8 cm or less, for example, 1 to 6 cm, 2 to 5 cm. In addition, the tube length is not particularly limited in principle, and can usually be 10 to 80 cm, preferably 20 to 50 cm.

[0142] Furthermore, the filling rate (filling volume rate) of the stationary phase in the tube can generally be 50 V% or more and 95 V% or less from the perspective of solid phase extraction efficiency.

[0143] The contacting step of the present invention mainly uses the above-mentioned stationary phase to completely adsorb the quantum dot system to be processed. For such an operation, the quantum dot system to be processed can also be injected into a tube containing the stationary phase with the aid of an injection device.

[0144] Extraction steps

[0145] After the contacting step, the extraction step of the present invention may be performed.

[0146] The extraction step of the present invention is mainly to elute non-target components other than the target quantum dot material. As mentioned above, the non-target components mainly include one or more of unreacted raw material components, solvents, excess or free ligand components and other impurity components (such as by-products during quantum dot synthesis).

[0147] In the present invention, the above elution is mainly performed by the difference in solvation (affinity) of the mobile phase. In the present invention, the mobile phase used in this step is also referred to as "extractant" for the convenience of distinguishing it from the mobile phase of the subsequent second elution step.

[0148] The extractant used in the extraction step of the present invention can be selected from one or more solvents, and these solvents can be single-component solvents or multi-component mixed solvents.

[0149] When these solvents are used as extractants, in some specific embodiments, the extractant has a lower solvation effect on the target quantum dots than on the non-target components. In other specific embodiments, multiple solvents can be used continuously to elute the non-target components. Among them, when each solvent is used as an extractant, the solvation effect on the target quantum dots is lower than the solvation effect on any one of the non-target components, and the extractant provides sufficient solvation for at least one of the non-target components to elute it from the stationary phase.

[0150] In some other specific embodiments, during the extraction step, the target quantum dots are precipitated on the surface of the stationary phase due to the use of an extractant.

[0151] In addition, due to the porous structure of the stationary phase surface, for example, it can accommodate target quantum dots with a wide particle size range, thereby ensuring that the recovery rate of the quantum dots is sufficient.

[0152] Furthermore, the strength of the difference in the solvation effect of the extractant or the degree of elution can be adjusted by one or more of the following methods:

[0153] i. Polarity of the extractant

[0154] ii. Solubility of the extractant

[0155] iii. Flow rate of the extractant

[0156] iv. Working time of the extractant

[0157] v. Extraction temperature.

[0158] Furthermore, the step of determining the completion of the extraction may be performed using conventional detection or monitoring methods in the art, which may include optical detection methods and the like.

[0159] In addition, the eluate in the first elution step can be collected by a solvent recovery or waste liquid collection device.

[0160] Elution steps

[0161] In the present invention, by performing the extraction step, all non-target components in the quantum dot system to be processed can be eluted. Furthermore, in the elution step, the mobile phase is adjusted to elute the target quantum dots from the stationary phase.

[0162] The mobile phase that can be used in the elution step can generally be selected according to the properties of the target quantum dots. The properties of the quantum dots here mainly include the properties of the functional groups on the surface of the quantum dots, the properties of the surface ligands, and the like.

[0163] For such a mobile phase, it is mainly to provide sufficient solvation (affinity) for the target quantum dots to elute the quantum dots adsorbed on the surface of the stationary phase. In the present invention, the mobile phase used in this step is also referred to as "eluent" for the convenience of distinguishing it from the mobile phase of the aforementioned extraction step.

[0164] The eluent used in the elution step of the present invention can be selected from one or more solvents, and these solvents can be single-component solvents or multi-component mixed solvents.

[0165] When these solvents are used as eluents, in some specific embodiments, the eluent can provide sufficient solvation for all target quantum dots so that all target quantum dots can be eluted from the surface of the stationary phase under the action of the eluent. In other specific embodiments, multiple solvents can be used continuously to elute the above-mentioned target quantum dot components. Among them, when each solvent is used as an eluent, the solvation effect on the target quantum dots in some particle size ranges is greater than that on the target quantum dots in other particle size ranges so that the former can be preferentially eluted from the stationary phase relative to the latter.

[0166] Furthermore, the strength of the difference in solvation of the eluent or the degree of elution can be adjusted by one or more of the following methods:

[0167] i. Polarity of the eluent

[0168] ii. Solubility of the eluent

[0169] iii. Eluent flow rate

[0170] iv. Working time of the eluent

[0171] v. Elution temperature.

[0172] Furthermore, the completion of the step of determining the elution may be performed by conventional detection or monitoring methods in the art, which may include optical detection methods and the like.

[0173] In addition, the fraction obtained in the elution step (purified product system) can be directly subjected to the particle size fractionation step (gel chromatography treatment) described below.

[0174] Steps of regeneration

[0175] The regeneration step of the present invention is mainly used to regenerate the stationary phase so that the stationary phase can be reused.

[0176] The regeneration step of the present invention includes using a cleaning agent to clean the stationary phase.

[0177] In principle, there is no particular limitation on the cleaning agent, as long as it can substantially completely desorb the components adsorbed on the stationary phase.

[0178] In some specific embodiments, the cleaning agent may be a fluid having a strong solvation effect on the quantum dot material, and examples of the fluid include organic solvents of a single type or a mixture of multiple substances, supercritical fluids, and the like.

[0179] In some other specific embodiments, the cleaning agent may be the same as or different from the mobile phase used in the above elution step.

[0180] Furthermore, the cleaning effect can be adjusted by adjusting the flow rate of the cleaning agent, the working time, the cleaning temperature and other conditions (if necessary).

[0181] Cleaning agents can also be recovered through solvent recovery devices.

[0182] In addition, in the regeneration step, the stationary phase after being cleaned with the cleaning agent may be further treated by heating, drying, etc. without limitation.

[0183] Continuous cycle processing / purification cycle processing

[0184] The purification steps of the present invention may be performed once or multiple times, or may be a continuous treatment method in which multiple cycles of the steps are sequentially performed.

[0185] In particular, when the cycle starts, while the regeneration step is being performed, at least one of the contacting step, the extracting step and the eluting step is being performed.

[0186] In some preferred embodiments of the present invention, after the regeneration step of the current cycle is completed, the contacting step of the next cycle can be immediately entered.

[0187] In some other preferred embodiments of the present invention, after the contacting step is completed, the next contacting step is immediately performed using a purified stationary phase / solid phase extraction column.

[0188] Such a continuous processing method provides the possibility for large-scale, online processing of quantum dot materials.

[0189] (Particle size classification steps)

[0190] The particle size classification step of the present invention is mainly based on gel chromatography to classify the particle size.

[0191] For gel chromatography, a porous gel material can be used as a stationary phase, and there is no particular limitation on such a material, which can be selected from an organic polymer or an inorganic material. Preferably, these materials are subjected to a hydrophobic surface treatment. Alternatively, the gel material can be an inorganic porous material, such as silica gel, alumina, etc.; an organic polymer, such as polyacrylamide gel, etc.; a porous material, such as porous crystalline polymers (COFs), porous organic polymers (POPs), etc.

[0192] Preferably, the gel material is metal organic frameworks (MOFs), covalent organic frameworks (COFs), porous organic polymers (POPs).

[0193] For the above materials, when necessary, they can be swollen by a solvent before use to make the internal pores more sufficient. In some preferred embodiments, when treating the above preferred types of quantum dot materials of the present invention, non-polar solvents can be used as swelling agents, for example, toluene, dichloroethylene, tetrachloroethylene, etc.

[0194] In principle, there is no particular limitation on the use of the above materials. Typically, for example, they can be filled into a tube in the form of spherical particles to form a gel chromatography column. Further, the target component containing the purified quantum dots is directly fractionated through the gel chromatography column, and the required mobile phase can be selected according to the characteristics of the quantum dots and the gel chromatography.

[0195] In addition, in some preferred embodiments of the present invention, after the particle size separation step, a step of regenerating the gel chromatography column (i.e., a cleaning step) may be included, and the gel medium (filled in the gel chromatography column) used for particle size classification may be cleaned, so that the gel chromatography column can be reused, thereby continuously performing the particle size classification process.

[0196] <Second Aspect>

[0197] In the second aspect of the present invention, Figure 1 As shown, a system or device for continuous, online processing of quantum dot materials is provided, which is used to perform the purification and particle size classification method described in the first aspect above.

[0198] Furthermore, the system or device mainly includes: a purification system and a classification system.

[0199] The purification system may include a sample injection unit, a solid phase extraction unit, and a sample recovery unit, and optionally a detection unit, a temperature control unit, a valve, a diversion unit, and the like.

[0200] Wherein, the sampling unit is used to place the quantum dot system to be processed. In some preferred embodiments, the sampling unit can be an automatic sampling unit, and preferably, can be connected to the quantum dot synthesis unit.

[0201] As for the solid phase extraction unit, it may include a mobile phase providing unit, a stationary phase unit and optionally a solvent / waste liquid recovery or collection unit.

[0202] The mobile phase supply unit may supply one or more solvents through a mobile phase pump.

[0203] For the stationary phase unit, it is preferred that it can be a cylindrical particle-filled column. In addition, in some other specific embodiments, the stationary phase unit has a plurality of substantially identical filling columns connected in parallel, such as 2 to 4, etc. Thus, when a filling column is regenerated, a new filling column can be directly used to perform the method in the first aspect, thereby improving the purification efficiency.

[0204] In addition, for the solvent collection unit, in some preferred embodiments, it can be allowed to be connected to the mobile phase providing unit to directly return the collected solvent to the mobile phase providing unit. For the waste liquid recovery unit, in some specific embodiments, it can also be allowed to be connected to the quantum dot synthesis unit to directly return the waste liquid to the quantum dot synthesis unit for new quantum dot synthesis.

[0205] The system or device for performing the above purification step of the present invention can perform one or more purification cycles of the present invention, and can realize online and continuous purification. Therefore, the continuous treatment of the present invention includes two meanings. On the one hand, it is the continuous purification of the directly obtained quantum dot reactants, and on the other hand, it can also further purify the purified system continuously.

[0206] Regarding the liquid inlet and outlet mode of the stationary phase, in order to improve the consistency of the liquid flow path and improve the purification efficiency, the present invention preferably enters from the lower end of the stationary phase unit and flows out from the upper end.

[0207] For the fractionation system, this may include a gel chromatography unit.

[0208] In some preferred embodiments, the gel chromatography unit may be a filled gel chromatography column. The gel particles filled in the gel chromatography column may have a diameter of 40 to 100 μm, and the filled inner diameter of the gel chromatography column may generally be 1 to 7 cm, and the length may be 10 to 30 cm.

[0209] In addition, the mobile phase required for the gel chromatography unit may be provided by the mobile phase supply unit in the above purification system, or by an additional independent mobile phase supply unit.

[0210] In some preferred embodiments, the gel chromatography column can be regenerated after use, for example, the mobile phase is used to continue flushing to clean the gel chromatography column. Therefore, in some other preferred embodiments, multiple, for example, 2-3 identical or different gel chromatography columns can be set in the gel chromatography unit, and when one gel chromatography column is regenerated, another gel chromatography column is used to grade the amount points.

[0211] For quantum dots treated with a gel chromatography column, quantum dot particles of different sizes can be collected at different retention times.

[0212] By means of the above-mentioned system or device for processing quantum dot materials of the present invention, the purification-particle size classification cycle of the present invention can be performed once or multiple times, and online, continuous, and rapid purification-particle size classification processing from quantum dot synthesis to final quantum dot classification / screening can be realized.

[0213] Example

[0214] The embodiments of the present invention will be described in detail below in conjunction with the examples, but those skilled in the art will appreciate that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If no specific conditions are specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be obtained commercially.

[0215] (Prepare materials)

[0216] Synthesis of quantum dot materials: CdSe quantum dot stock solution was synthesized by hot injection or microfluidics, and its absorption peak position, concentration, and half-peak width were detected by Agilent Cary 8454 UV-visible spectrophotometer. The obtained quantum dot stock solution was divided into two groups, group 1 and group 2.

[0217] Solid phase extraction column filler (two identical columns, column A and column B): fill the modified glass microspheres into the solid phase extraction column (filling range 50% to 100%), tighten the lid and set aside. The diameter of the glass microspheres is 200 μm; column specifications: inner diameter 3 cm, length 40 cm.

[0218] Gel permeation chromatography column filler (column X): Disperse 100g of gel medium in 1000mL of toluene / dichloromethane / tetrachloroethylene solvent, let stand for 12 hours, then fill the dispersion into the gel permeation chromatography column (fill), tighten the lid and set aside. The diameter of the gel medium is 60μm; column specifications: inner diameter 20mm, length 120mm.

[0219] (Purification and Fractionation)

[0220] Quantum dot adsorption process (contact step): open valve 1, valve 3, valve 4, valve 6, valve 7, turn on the HPLC liquid phase pump, and adjust the pump speed to 10mL min -1 , draw 10mL of quantum dot stock solution 1 into the syringe, and adjust the injection speed to 10mL·min -1 ; Two phases are injected simultaneously, and the injection speed ratio of the peristaltic pump (controlling the injection of quantum dot stock solution) and the HPLC pump is controlled at 3 (the ratio of quantum dots and extractant is regulated by controlling the injection speed ratio). After the quantum dot solution is injected into column A, close the peristaltic pump and valve 4; after the contact step is completed, switch to column B to continue the step of contacting the quantum dot stock solution group 2.

[0221] Elution process (including extraction and elution steps): HPLC pump injection speed is adjusted to 10 mL min -1And adjust valves 1 and 2 to adjust the composition of the mobile phase, and then wash the adsorbed quantum dots to remove non-target components respectively, and elute the target component, and the time is controlled to be 10 minutes. After the elution is completed, close valves 1, 3, 4, 6, 7, and the HPLC pump, and the target component enters the gel permeation chromatography column X, and then regenerate column A according to the following steps. After the regeneration, column A can continue to repeat the above purification steps. After column A enters regeneration, column B waits for the regeneration of column X and then performs the above elution process, so that the target component in the original liquid group 1 enters column X.

[0222] Particle size screening process: After the target component enters column X, open valve 2, valve 3, valve 5, valve 8, turn on the HPLC pump, and adjust the pump speed to 10 mL min -1 , samples were collected according to different retention times to obtain quantum dot solutions with different particle sizes.

[0223] Regeneration of solid phase extraction column: open valve 4, valve 6, valve 7, draw 10mL of eluent from the syringe, and adjust the peristaltic pump injection speed to 10mL min -1 After the residual quantum dots in the pipeline are rinsed clean, close the peristaltic pump and valve 4. Open valves 1, 3, 6, and 7, turn on the HPLC pump, and adjust the pump speed to 10 mL min -1 , time 1min, after injection, close valve 1. Open valve 2, turn on the HPLC pump, adjust the pump speed to 10mL·min-1, time 1min, after injection, close valve 2. Repeat the above steps 4 times.

[0224] Gel permeation chromatography column regeneration: Open valve 1, valve 3, valve 5, valve 7, turn on the HPLC pump, and adjust the pump speed to 10 mL min -1 , time 1min, close valve 1 after injection. Open valve 2, turn on the HPLC pump, and adjust the pump speed to 10mL·min -1 , time 1min, close valve 2 after injection. Repeat the above steps 5 times.

[0225] Evaluation of purification results:

[0226] After diluting the solution before and after purification to a certain concentration, use a pipette to draw 10-15 μL of it and apply it on a glass slide. After drying, observe the morphology under a microscope (such as Figure 2 ). The results showed that there were a lot of impurities in the membrane before purification, but no impurities in the membrane after purification, indicating that the purification was effective.

[0227] It should be noted that, although the technical solution of the present invention is introduced with specific examples, those skilled in the art will appreciate that the present invention should not be limited thereto.

[0228] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A continuous processing method, which is a continuous processing method for quantum dot materials, characterized in that: The method comprises the following steps: A purification step, purifying the quantum dot system to be treated to obtain purified quantum dots, and a particle size classification step, wherein the purified quantum dots are subjected to online particle size classification using gel chromatography; A cleaning step for cleaning the gel medium used for particle size classification; Wherein, the purification step comprises: A contacting step, so that the quantum dot system to be treated contacts with the stationary phase; An extraction step, using an extractant to elute non-target components in the quantum dot system to be treated, wherein the non-target components include one or more of unreacted components, impurity components, and free ligand components, and the target components are substantially retained in the stationary phase during the extraction step; an elution step, using an eluent to elute the target component from the stationary phase; a regeneration step, wherein the regeneration step comprises using a cleaning agent to clean the stationary phase; In the purification step, the above steps or cycles formed by each step are performed once or multiple times to continuously perform the purification step. And, the target component includes the purified quantum dots.

2. The processing method according to claim 1, characterized in that: The quantum dot system to be treated is an untreated reaction product system directly obtained from the synthesis reaction of the quantum dot material; the regeneration step also includes a step of drying the stationary phase after cleaning.

3. The processing method according to claim 1 or 2, characterized in that: The quantum dot system to be processed is one of an oily quantum dot system and an aqueous quantum dot system.

4. The processing method according to any one of claims 1 to 3, characterized in that: The stationary phase consists of particles whose surfaces are modified by silanes having long-chain alkyl groups.

5. The processing method according to any one of claims 1 to 4, characterized in that: In the purification step, a cycle formed by the above steps is performed one or more times, and after the cycle starts, while the regeneration step is being performed, at least one of the contacting step, the extraction step, and the elution step is being performed.

6. The processing method according to any one of claims 1 to 5, characterized in that: In the extraction step, the non-target components are eluted by the solvation of the extractant, and / or, one or more of the following conditions are adjusted in the extraction step to elute the non-target components: i. Polarity of the extractant ii. Solubility of the extractant iii. Flow rate of the extractant iv. Working time of the extractant v. Extraction temperature.

7. The processing method according to any one of claims 1 to 6, characterized in that: In the eluting step, one or more eluents are used to elute the target component through the solvation of the eluents; and / or, In the elution step, one or more of the following conditions are adjusted to elute the target component: i. Polarity of the eluent ii. Solubility of the eluent iii. Eluent flow rate iv. Working time of the eluent v. Elution temperature.

8. The processing method according to any one of claims 1 to 7, characterized in that: The target components including the purified quantum dots are directly processed using gel chromatography, and optionally, the gel chromatography includes processing using a porous gel material.

9. A device for the treatment method according to any one of claims 1 to 8, characterized in that: The device comprises: Purification system and grading system, Wherein, the purification system comprises: Injection unit, solid phase extraction unit and sample recovery unit, The sample injection unit is used to place the quantum dot system to be processed. The solid phase extraction unit comprises a mobile phase providing unit, a stationary phase unit and optionally a solvent / waste liquid collecting unit; The grading system includes: A gel chromatography unit connected in series with the stationary phase unit, wherein the mobile phase required by the gel chromatography unit of the fractionation system is provided via the mobile phase providing unit in the purification system or via an additional mobile phase providing unit different therefrom.

10. A method for preparing quantum dots, characterized in that: The method comprises: Steps for synthesizing quantum dot materials; Successive processing steps of quantum dot materials, The step of continuously treating the quantum dot material comprises treating a reaction product system obtained by the step of synthesizing the quantum dot material according to the continuous treatment method according to any one of claims 1 to 8.

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