Quantum dot online production system and quantum dot production method

Abstract

The invention relates to a quantum dot online production system and a quantum dot production method. The quantum dot online production system comprises a quantum dot synthesis part and a quantum dot purification part, wherein the quantum dot synthesis part comprises a precursor reaction unit; a precursor conveying unit; a quantum dot synthesis unit; an online monitoring unit; the precursor reaction unit, the precursor conveying unit, the quantum dot synthesis unit and the product collection unit are communicated in sequence, and the online monitoring unit is located between the quantum dot synthesis unit and the product collection unit. By adopting the quantum dot online production system disclosed by the invention, integrated online production and purification from raw materials to high-purity quantum dot products can be realized. The quality of the quantum dots is improved through real-time high-precision regulation and control of reaction conditions in the synthesis process, and full-automatic and uninterrupted continuous production is achieved.

Description

Technical Field

[0001] The invention relates to a quantum dot online production system and a method for producing quantum dots, and belongs to the field of fine material synthesis. Background Art

[0002] Traditional methods of synthesizing quantum dots often involve the control of temperature, solvent, pressure or other reaction conditions of chemical reactions. These reaction conditions are usually difficult to control well, such as the need to quickly add the precursor solution to the reaction vessel to prevent the precursor from being oxidized, and the need to stir and mix the two solutions for a long time to allow the molecules in the two solutions to fully fuse and react completely.

[0003] Therefore, the reaction conditions of the traditional method of synthesizing quantum dots are difficult to control precisely, manual operations are highly random, batch differences are large, and it is difficult to achieve continuous production.

[0004] Moreover, real-time monitoring during the reaction process is also a common problem encountered in traditional laboratory synthesis of nanomaterials. For example, when synthesizing fluorescent quantum dots, the reaction is carried out in a three-necked flask, and a handheld ultraviolet lamp is often used to monitor the fluorescence. However, the fluorescence monitored through the reaction container is not accurate because the reaction container refraction and absorption of light, and when the emission light is in the blue band, some reactants are prone to absorb this band, which causes a lot of errors in real-time monitoring.

[0005] In addition, in the existing methods for synthesizing quantum dots, the precursor preparation and quantum dot synthesis and purification processes are relatively independent modules, and it is impossible to achieve integrated online synthesis and online purification from the initial raw materials to the final high-purity quantum dot products. Summary of the invention

[0006] Problem that the invention aims to solve

[0007] Based on the above-mentioned problems existing in the prior art, the present invention provides a quantum dot online production system and a method for producing quantum dots. The quantum dot production system of the present invention can realize online synthesis and purification from raw materials to quantum dots; realize real-time and high-precision control of reaction conditions during the quantum dot synthesis process; at the same time, through the online continuous purification of quantum dots, the quality of quantum dots is improved, the production efficiency is improved, and the fully automatic, uninterrupted and continuous production of high-purity quantum dots is realized.

[0008] Solutions for solving problems

[0009] The present invention provides a quantum dot online production system, which comprises: a quantum dot synthesis part and a quantum dot purification part;

[0010] The quantum dot synthesis unit comprises: a precursor reaction unit; a precursor delivery unit; a quantum dot synthesis unit; an online monitoring unit; and a product collection unit. The precursor reaction unit, the precursor delivery unit, the quantum dot synthesis unit and the product collection unit are connected in sequence, and the online monitoring unit is located between the quantum dot synthesis unit and the product collection unit.

[0011] The quantum dot purification unit comprises: an extraction unit, a liquid supply unit, a first driving unit and a liquid outlet unit.

[0012] Wherein, the extraction unit comprises a plurality of extraction columns;

[0013] Wherein, the liquid supply unit comprises a plurality of liquid supply pipes for supplying reagents of each purification stage to the extraction column, and one of the liquid supply pipes is used to communicate with the product collection unit and supply the collected product to the extraction column;

[0014] Wherein, the liquid outlet unit comprises a plurality of liquid outlet pipes for discharging the liquid produced in each purification stage;

[0015] Wherein, the first driving unit is used to drive the extraction unit to rotate so that the extraction column can be connected with the liquid supply pipe at different positions at different times, so that the plurality of extraction columns are respectively in different purification stages.

[0016] According to the quantum dot online production system of the present invention, the quantum dot purification section includes two second driving units, which are respectively connected to the liquid supply unit and the liquid outlet unit, and are used to respectively drive the liquid supply pipe in the liquid supply unit and the liquid outlet pipe in the liquid outlet unit to connect and disconnect with the extraction column.

[0017] According to the quantum dot online production system of the present invention, a solid phase unit is provided in the extraction column, and the solid phase unit includes basic microspheres with glass surfaces and silanes containing alkoxy groups and alkyl groups with 6-36 carbon atoms grafted on the surfaces of the basic microspheres.

[0018] According to the quantum dot online production system of the present invention, the precursor reaction unit includes at least a first reactor and a second reactor, the first reactor and / or the second reactor respectively include more than two reaction chambers, and the first reactor and the second reactor are respectively connected to the precursor delivery unit through a switching device.

[0019] According to the quantum dot online production system of the present invention, the precursor delivery unit includes a flow controller.

[0020] According to the quantum dot online production system of the present invention, the quantum dot synthesis unit includes a pipeline for passing the precursor, the quantum dot synthesis unit includes a pressurizer and / or a magnetizer, the quantum dot synthesis unit includes an oil bath heater, a sand bath heater, an electric heater or a magnetic thermal heater; and / or,

[0021] The quantum dot synthesis unit 3 includes at least one reaction zone, and the reaction conditions of each reaction zone are independently controlled.

[0022] According to the quantum dot online production system of the present invention, the online monitoring unit includes a spectroscopic analyzer and / or a nuclear magnetic resonance analyzer. The spectroscopic analyzer can monitor at least one of the emission peak position, half-peak width, absorption intensity, trough position, and quantum dot yield of the quantum dots. The nuclear magnetic resonance analyzer is used to analyze the hydrogen spectrum of the quantum dots.

[0023] According to the quantum dot online production system of the present invention, the product collection unit includes a liquid storage portion, the liquid storage portion includes more than one liquid reservoir, and the liquid reservoir includes a liquid level sensor.

[0024] According to the quantum dot online production system described in the present invention, the extraction column includes an inlet that can be connected to the liquid outlet of the liquid supply pipe and an outlet that can be connected to the liquid inlet of the liquid outlet pipe, and the liquid outlet of the liquid supply pipe and / or the liquid inlet of the liquid outlet pipe both include a conical guide port and a sealing ring.

[0025] The present invention also provides a method for producing quantum dots, which uses the quantum dot online production system of the present invention to produce quantum dots.

[0026] Effects of the Invention

[0027] The quantum dot online production system of the present invention can realize integrated online production and purification from raw materials to high-purity quantum dot products. The quality of quantum dots can be improved by real-time high-precision control of reaction conditions during the synthesis process. At the same time, the integrated online purification system can realize fully automatic, uninterrupted continuous production, greatly improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the quantum dot online production system of the present invention;

[0029] Figure 2 A schematic diagram of a quantum dot synthesis unit of a quantum dot online production system of the present invention;

[0030] Figure 3 A schematic diagram of a precursor reaction unit of a quantum dot synthesis section of a quantum dot online production system of the present invention;

[0031] Figure 4A schematic diagram of a quantum dot purification unit of a quantum dot online production system of the present invention;

[0032] Figure 5a-Figure 5b Schematic diagram of a liquid inlet unit or a liquid outlet unit of a quantum dot purification section of a quantum dot online production system of the present invention;

[0033] Figure 6a-6c A schematic diagram of a heater of a reaction unit of a quantum dot synthesis section of a quantum dot online production system of the present invention;

[0034] Figure 7a-7c A schematic diagram of a cooler of a product collection unit of a quantum dot synthesis section of a quantum dot online production system of the present invention;

[0035] Figure 8 Schematic diagram of an online monitoring unit of the quantum dot online production system used in Example 1;

[0036] 1. Precursor reaction unit; 1-1. First reactor; 1-2. Second reactor; 2. Precursor delivery unit; 3. Reaction unit; 4. Online monitoring unit; 5. Product collection unit; 6. Control panel; 7. Solenoid valve; 9. Liquid supply unit; 10. Extraction unit; 11. Liquid outlet unit; 12. First drive unit; 121. First rotating shaft; 122. Second rotating shaft; 123. Gear; 13. Second drive unit; 14. Conical guide port; 15. O-ring; 16. Fixed flange; 17 / 18. Liquid inlet pipe / liquid outlet pipe; 19. Sample inlet of cooler; 20. Sample outlet of cooler; 21. Fan of cooler; 22. Coolant of cooler; 23. Coolant inlet; 24. Coolant outlet, 25. Pipeline of heater. DETAILED DESCRIPTION

[0037] The following describes the embodiments of the present invention, but the present invention is not limited thereto. The present invention is not limited to the various structures described below, and various changes can be made within the scope of the invention claim, and the embodiments and embodiments obtained by appropriately combining the technical means disclosed in different embodiments and embodiments are also included in the technical scope of the present invention. In addition, all the documents recorded in this specification are cited in this specification as references.

[0038] Unless defined otherwise, technical and scientific terms used herein include the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0039] In this specification, the numerical range expressed using "numerical value A to numerical value B" or "numerical value A-numerical value B" means a range including the endpoints numerical values ​​A and B.

[0040] In this specification, the meaning of "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process. In this specification, "optional" or "optionally" means that the event or situation described below may or may not occur, and the description includes the situation where the event occurs and the situation where the event does not occur.

[0041] In this specification, when "%" appears, it means mass or weight percentage, that is, "mass %" or "weight %", unless otherwise specified.

[0042] In this specification, the use of “substantially” or “essentially” means that the range of industrial error or experimental error is taken into consideration.

[0043] In this specification, the references to "some specific / preferred embodiments", "other specific / preferred embodiments", "some specific / preferred technical solutions", "other specific / preferred technical solutions", etc. refer to the specific elements (e.g., features, structures, properties and / or characteristics) related to the embodiments described herein being 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.

[0044] The term "comprising" and any variations thereof in the specification and claims of the present invention and the above drawings are intended to cover non-exclusive inclusions. For example, a process, method or system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0045] The first invention

[0046] The present invention provides a quantum dot online synthesis system, such as Figure 1 As shown, the quantum dot online production system includes: a quantum dot synthesis section and a quantum dot purification section;

[0047] The quantum dot synthesis unit comprises: a precursor reaction unit 1; a precursor delivery unit 2; a quantum dot synthesis unit 3; an online monitoring unit 4 and a product collection unit 5. The precursor reaction unit 1, the precursor delivery unit 2, the quantum dot synthesis unit 3 and the product collection unit 5 are connected in sequence, and the online monitoring unit 4 is located between the quantum dot synthesis unit 3 and the product collection unit 5.

[0048] The quantum dot purification unit includes: an extraction unit 10, a liquid supply unit 9, a first driving unit 12 and a liquid outlet unit 11.

[0049] Wherein, the extraction unit 10 includes a plurality of extraction columns;

[0050] The liquid supply unit 9 includes a plurality of liquid supply tubes for supplying reagents for each purification stage to the extraction column, and one of the liquid supply tubes is used to communicate with the product collection unit 5 and provide the collected product to the extraction column;

[0051] Wherein, the liquid outlet unit 11 includes a plurality of liquid outlet pipes for discharging the liquid produced in each purification stage;

[0052] The first driving unit 12 is used to drive the extraction unit 10 to rotate so that the extraction columns can be connected to the liquid supply pipes at different positions at different times, so that the plurality of extraction columns are respectively in different purification stages.

[0053] According to the quantum dot online production system of the present invention, Figure 2 and Figure 3 As shown, the precursor reaction unit 1 includes at least a first reactor 1-1 and a second reactor 1-2, the first reactor 1-1 and / or the second reactor 1-2 respectively include more than two reaction chambers, and the first reactor 1-1 and the second reactor 1-2 are respectively connected to the precursor delivery unit 2 through a switch device. In the process of synthesizing quantum dots, it is usually necessary to prepare a variety of reaction precursors. By including more than two reactors, more than two reaction precursors can be prepared simultaneously, thereby improving production efficiency. In addition, the precursor reaction unit also includes an additive container directly delivered to the reaction chamber, and the amount of the additive container added to the reaction chamber is controllable.

[0054] According to the quantum dot online production system of the present invention, the precursor delivery unit 2 includes a flow controller to control the flow rate of the precursor entering the quantum dot synthesis unit 3. By adjusting the injection flow rate ratio of different precursors, diversified synthesis of peak shapes can be achieved.

[0055] According to the quantum dot online production system of the present invention, the quantum dot synthesis unit 3 includes a pipeline for allowing the precursor to pass through, the quantum dot synthesis unit 3 includes at least one of a pressurizer, a magnetizer, and an illuminator, and the quantum dot synthesis unit 3 includes an oil bath heater or a sand bath heater or an electric heater or a magnetic thermal heater.

[0056] In a possible preferred embodiment, Figure 6a As shown, the quantum dot synthesis unit 3 includes an oil bath heater, in which the pipeline 25 is distributed in a serpentine shape; Figure 6b As shown, the quantum dot synthesis unit 3 includes a sand bath heater, and the pipeline 25 is distributed in a spiral shape; Figure 6cAs shown, the quantum dot synthesis unit 3 includes an electric heater, and the pipeline 25 is wound and distributed on the electric heating rod. By using the above heater, the capacity of the reaction unit can be expanded and the heating uniformity can be ensured.

[0057] Preferably, the quantum dot synthesis unit includes at least one reaction zone, and the reaction conditions of each reaction zone are independently controlled, so that the reaction conditions can be set according to the needs of each reaction zone, thereby improving the practicality of the quantum dot online synthesis system.

[0058] Preferably, the quantum dot synthesis unit 3 comprises a temperature control module, which can control the heater to regulate the reaction temperature with a temperature control accuracy of 1°C and a fastest heating rate of 10°C / min.

[0059] According to the quantum dot online production system of the present invention, the online monitoring unit 4 includes a spectrum analyzer and / or a nuclear magnetic analyzer, and the spectrum analyzer can monitor at least one of the emission peak position, half-peak width, and absorption intensity of the quantum dots online. Optionally, in a specific embodiment, the spectrum analyzer is a fluorescence spectrum analyzer or an absorption spectrum analyzer.

[0060] During the synthesis process, if the peak position displayed by the online monitoring unit 4 is smaller than the target peak position, the injection rate of the flow controller of the precursor delivery unit 1 can be reduced or the temperature of the reaction unit can be appropriately reduced. On the contrary, if the peak position displayed by the online monitoring unit 4 is larger than the target peak position, the injection rate of the flow controller of the precursor delivery unit 1 can be increased or the temperature of the reaction unit can be appropriately increased until the displayed peak position matches the target peak. The efficiency of the quantum dot online production system is improved, and the quality of the synthesized quantum dots is improved.

[0061] According to the quantum dot online production system described in the present invention, the product collection unit 5 includes a liquid storage part, the liquid storage part includes more than one liquid reservoir, and the liquid reservoir includes a liquid level sensor. By arranging a liquid level sensor in the liquid reservoir, the liquid level of the liquid reservoir can be measured. When the liquid level reaches a preset value, it can be automatically switched to another liquid reservoir for liquid storage. In addition, the liquid level can be monitored in real time by the arranged liquid level sensor. When the liquid in the liquid reservoir connected to the liquid supply pipe of the quantum dot purification part is low, the liquid storage part can be controlled to rotate and switch to another liquid reservoir to be connected to the liquid supply pipe, so as to facilitate the continuity of the quantum dot online synthesis system, so that the production efficiency of the quantum dot synthesis part and the quantum dot purification part match each other.

[0062] In a possible preferred embodiment, a cooler is included in the product collection unit 5, such as Figure 7a As shown, the cooler includes a fan 21, the product enters through the inlet 19, flows out through the outlet 20, and is cooled by the fan 21; Figure 7bAs shown, the cooler includes a pipeline immersed in a cooling liquid 22, and the product enters through the inlet 19 and flows out through the outlet 20, and is cooled by the pipeline immersed in the static cooling liquid 22; Figure 7c As shown, the cooler includes a coolant 22 flow pipeline, the coolant enters from the inlet 23 of the coolant flow pipeline, and flows out from the outlet 24. The product flow pipeline passes through the coolant flow pipeline, the product enters through the injection port 19, and flows out through the outlet 20, and is cooled by the product flow pipeline immersed in the coolant 22.

[0063] like Figure 4 As shown, according to the quantum dot online production system of the present invention, the quantum dot purification section includes two second driving units 13, which are respectively connected to the liquid supply unit 9 and the liquid outlet unit 11, and are used to respectively drive the liquid supply pipe in the liquid supply unit 9 and the liquid outlet pipe in the liquid outlet unit 11 to connect and disconnect with the extraction column.

[0064] The multiple liquid supply pipes in the liquid supply unit 9 can be respectively fed with different solutions. The specific structure of the first driving unit 12 can be various, for example: a motor and a gear, a motor and a connecting rod, etc. Figure 4 As shown, the first drive unit includes a first rotating shaft 121 and a second rotating shaft 122, each of which is fixed with a gear 123, wherein a plurality of extraction columns are built into the first rotating shaft 121, and can be arranged along the circumference of the first rotating shaft 121, preferably arranged at equal intervals. The first rotating shaft 121 and the second rotating shaft 122 are meshed and driven by the gear 123, and the second rotating shaft 122 is connected to the motor, and the motor drives the second rotating shaft 122 to rotate, and the meshed gear 123 can further drive the first rotating shaft 121 to rotate, so that each extraction column passes through a predetermined position in time and communicates with the corresponding liquid supply pipe and liquid outlet pipe. The liquid outlet pipe in the liquid outlet unit 11 includes an outlet for discharging the solution. The second drive unit 13 is preferably a linear cylinder assembly, which exists in both the liquid supply unit 9 and the liquid outlet unit 11, and is used to push the liquid supply pipe in the liquid supply unit 9 upward and the liquid outlet pipe in the liquid outlet unit 11 downward, so as to achieve a close connection between the inlet, the outlet and the extraction column. The optional second drive unit can also be a motor and a connecting rod structure.

[0065] According to the quantum dot online production system of the present invention, the extraction column includes a solid phase unit, which includes a basic microsphere with a surface made of glass and a silane containing an alkoxy group and an alkyl group with a carbon number of 6 to 36 grafted on the surface of the basic microsphere. The solid phase unit can efficiently and stably purify the quantum dot material contained in the quantum dot stock solution and can be used repeatedly.

[0066] like Figure 5bAs shown, according to the quantum dot online production system of the present invention, the extraction column includes an inlet that can be connected to the liquid outlet of the liquid supply pipe and an outlet that can be connected to the liquid inlet of the liquid outlet pipe. The liquid outlet of the liquid supply pipe and the liquid inlet of the liquid outlet pipe both include a guide port 14 and a sealing ring 15. The cross section of the guide port 14 can be a figure with a narrow upper part and a wide lower part, preferably a cone or a trapezoid. The sealing ring 15 is sleeved on the outside of the guide port to facilitate the liquid outlet pipe and the liquid supply pipe to be sealed and connected with the corresponding extraction column.

[0067] In an optional embodiment, in the quantum dot purification section, the liquid supply unit 9 includes 5 liquid supply tubes, the extraction unit 10 includes 5 extraction columns, and the liquid outlet unit 11 includes 5 liquid outlet tubes. The liquid supply process, the liquid outlet process, and the circulation process of the extraction column are all program-controlled, thereby realizing a fully automatic, uninterrupted and continuous solid phase extraction process.

[0068] Among them, Figure 5a As shown, the number of the liquid supply pipe of the liquid supply unit 9, the extraction column of the extraction unit 10, and the liquid outlet pipe of the liquid outlet unit 11 are all 5, and the numbering rules are consistent, and they are all numbered as a, b, c, d, and e in clockwise order from the upward direction. Preferably, the structure of the liquid supply pipe and the liquid outlet pipe is similar, and both include a conical guide port 14, an O-shaped sealing ring 15, a fixing flange 16, and a liquid transmission hose 17 / 18, which can quickly form a sealed state with the column body of the extraction column to prevent leakage when passing liquid.

[0069] Different solutions are introduced into the five liquid supply pipes in the liquid supply unit. Figure 4 As shown, it comprises two first rotating shafts 121 and a second rotating shaft 122 with gears 123, wherein 5 extraction columns are built-in and fixed in the first rotating shaft 121, and the second rotating shaft 122 is connected to the motor, which drives the second rotating shaft 122 to rotate, and through the meshing gear 123, it can further drive the first rotating shaft 121 to rotate, so that the column body of each extraction column passes through the five positions a, b, c, d, and e in sequence; the inlet direction of the column body of the extraction column is provided with a membrane or valve for controlling the unidirectional flow of the liquid. The liquid discharged from the liquid outlet pipe can be selected to be discharged into the waste liquid pool or collected. The second driving unit 13 can be a linear cylinder assembly, which exists in both the liquid supply unit 9 and the liquid outlet unit 11, and is used to push the liquid supply pipe in the liquid supply unit 9 upward and the liquid outlet pipe in the liquid outlet unit 11 downward, so as to achieve a close connection between the inlet and the outlet and the extraction column.

[0070] Preferably, an example is given to illustrate a use cycle of the quantum dot purification unit, assuming that the position number of the extraction column in the fixed flange is consistent with the position number of the liquid supply pipe and the liquid outlet pipe as the initial position of the device. Taking the first extraction column at position a of the initial position as an example, the specific operation process is as follows.

[0071] ① The device is in contact with the closed state. The inlet of the liquid supply pipe at position a passes the solution La into the first extraction column, and its flow rate is controlled to be va and the liquid passing time is ta. At the same time, the outlet of the liquid outlet pipe at position a discharges the liquid. After the liquid passing is completed, the device returns to the separation state.

[0072] ② The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches position b, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact and closed state; the inlet of the liquid supply pipe at position b passes the solution Lb into the first extraction column, and its flow rate is controlled to be vb and the liquid passing time is tb. At the same time, the outlet of the liquid outlet pipe at position b discharges the liquid; after the liquid passing is completed, the device returns to the separation state.

[0073] ③ The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches position c, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact closed state; the inlet of the liquid supply pipe at position c passes the solution Lc into the first extraction column, and its flow rate is controlled to be vc and the liquid passing time is tc. At the same time, the outlet of the liquid outlet pipe at position c discharges the liquid; after the liquid passing is completed, the device returns to the separation state.

[0074] ④ The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches position d, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact closed state; the inlet of the liquid supply pipe at position d passes the solution Ld into the first extraction column, and its flow rate is controlled to be vd and the liquid passing time is td. At the same time, the outlet of the liquid outlet pipe at position d discharges the liquid; after the liquid passing is completed, the device returns to the separation state.

[0075] ⑤ The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches the e position, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact closed state; the inlet of the e-position liquid supply pipe passes the solution Le into the first extraction column, and its flow rate is controlled to be ve and the liquid passing time is te. At the same time, the outlet of the e-position liquid outlet pipe discharges the liquid; after the liquid passing is completed, the device returns to the separation state.

[0076] ⑥ The fixed flange is driven by the first driving unit 12 to rotate clockwise, so that the first extraction column returns to position a and undergoes the above process again.

[0077] When the quantum dot purification unit is running, a total of 5 extraction columns perform solid phase extraction simultaneously and in sequence. The rotation speed of the first drive unit 12 can be set as needed. Through cooperation with the synthesis unit, continuous solid phase extraction of large quantities of samples to be processed and continuous collection of processed samples are achieved. In addition, the rotation of the first drive unit 12, the control of the liquid supply unit 9 and the liquid outlet unit 11, and the control of the contact state and the separation state are all completed by program control. The operator only needs to set the relevant parameters before starting the operation, and no operation is required during the operation. That is, the entire process realizes continuous online full automation.

[0078] Second aspect

[0079] The present invention also provides a method for producing quantum dots, which uses the quantum dot online production system of the present invention to synthesize and purify the quantum dots.

[0080] When using the quantum dot online production system described in the present invention, online and continuous synthesis and purification of quantum dots can be achieved. There is no special restriction on the process of synthesizing and purifying quantum dots. Taking the synthesis and purification of CdSe quantum dots as an example, the synthesis and purification process of quantum dots is briefly described.

[0081] First, quantum dots are synthesized in a quantum dot synthesis unit.

[0082] Preparation of precursors

[0083] The precursor is synthesized in the precursor reaction unit 1. The method for preparing the precursor is not particularly limited. For example, the precursor can be prepared by the following steps.

[0084] Step 1: Add the raw materials required for preparing the cadmium precursor solution into the first reaction chamber 1-1-1 and the second reaction chamber 1-1-2 of the first reactor 1-1 of the precursor reaction unit 1, close the solenoid valve, set the target temperature, insulation time and stirring speed on the control panel, run the program, and the cadmium precursor can be obtained after the program ends.

[0085] Step 2: Add the raw materials required for preparing the selenium precursor solution into the first reaction chamber 1-2-1 and the second reaction chamber 1-2-2 of the second reactor 1-2 of the precursor reaction unit 1 respectively, close the solenoid valve, set the target temperature, insulation time and stirring speed on the control panel, run the program, and the selenium precursor can be obtained after the program ends.

[0086] Precursor delivery

[0087] As long as the precursor can be transported to the quantum dot synthesis unit 3 via the precursor transport unit 2, there is no particular limitation on the transport process of the precursor. For example, the cadmium precursor obtained by the first reactor 1-1 is pumped via the first injection pump, and the selenium precursor obtained by the second reactor 1-2 is pumped via the second injection pump, and then mixed in the mixer and transported to the quantum dot synthesis unit 3.

[0088] Synthesis of quantum dots

[0089] The precursor is transported to the quantum dot synthesis unit 3 via the precursor transport unit 2, the heating temperature is set, the flow rates of the cadmium precursor and the selenium precursor are set respectively, and the pressure is adjusted so that the reaction is in a high-pressure environment; after the reaction under the supercritical state, the quantum dots are produced, and the obtained quantum dot samples are monitored by the online monitoring unit 4. The quantum dots synthesized by the quantum dot online synthesis system have a narrow half-peak width.

[0090] Collection of quantum dots

[0091] The product collection unit 5 collects the produced quantum dots. Preferably, as described above, the liquid storage part of the product collection unit 5 includes more than one liquid reservoir, and the liquid reservoir includes a liquid level sensor. Through the liquid level sensor monitoring, after the liquid reservoir reaches a set full liquid state, it switches to the next liquid reservoir for collection, thereby realizing automatic collection of quantum dots.

[0092] Subsequently, the synthesized quantum dots are purified in the quantum dot purification unit.

[0093] The quantum dot purification process of the present invention is carried out by solid phase extraction. Preferably, the solid phase extraction includes five steps: pretreatment, loading, cleaning, elution, and regeneration. Accordingly, the liquid supply unit 9 includes five liquid supply tubes, the extraction unit 10 includes five extraction columns, and the liquid outlet unit 11 includes five liquid outlet tubes.

[0094] The liquid supply process, liquid discharge process, and circulation process of the extraction column are all controlled by a program, thereby realizing a fully automatic, uninterrupted and continuous solid phase extraction process.

[0095] The number of the liquid supply pipe of the liquid supply unit 9, the extraction column of the extraction unit 10, and the liquid outlet pipe of the liquid outlet unit 11 are all 5, and the numbering rules are consistent, and they are numbered a, b, c, d, and e in clockwise order from the upward direction. Preferably, the structure of the liquid supply pipe and the liquid outlet pipe is similar, and both include a tapered guide port 14, an O-ring 15, a fixed flange 16, and a liquid transmission hose 17 / 18, which can quickly form a sealed state with the column body of the extraction column to prevent leakage when passing liquid.

[0096] The five liquid supply pipes in the liquid supply unit are respectively fed with pretreatment liquid, synthesized quantum dots, cleaning liquid, elution liquid, and regeneration liquid. Figure 4 As shown, the first rotating shaft 121 can be driven to rotate so that the body of each extraction column passes through the five positions a, b, c, d, and e in sequence; the inlet direction of the body of the extraction column is provided with a membrane or valve for controlling the unidirectional flow of the liquid. The liquid outlet pipe in the liquid outlet unit 11 includes 5 outlets, among which the effluent from the outlet at position d needs to be recovered as the purified quantum dots, and the others are discharged as waste liquid. The second driving unit 13 can be a linear cylinder assembly, which exists in both the liquid supply unit 9 and the liquid outlet unit 11, and is used to push the liquid supply pipe in the liquid supply unit 9 upward and the liquid outlet pipe in the liquid outlet unit 11 downward, so as to achieve a close connection between the inlet, outlet and the extraction column.

[0097] When the position number of the extraction column in the fixed flange is consistent with the position number of the liquid supply pipe and the liquid outlet pipe, the device is in the initial position. Taking the first extraction column at position a of the initial position as an example, the specific operation process is as follows.

[0098] ① The device is in contact with the closed state. The inlet of the liquid supply pipe at position a passes the pretreated liquid La into the first extraction column, and its flow rate is controlled to be va and the liquid flow time is ta. At the same time, the outlet of the liquid outlet pipe at position a discharges the liquid into the waste liquid pool a. After the liquid flow is completed, the device returns to the separation state.

[0099] ② The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches position b, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact closed state; the inlet of the liquid supply pipe at position b passes the sample solution Lb into the first extraction column, and its flow rate is controlled to be vb and the liquid passing time is tb. At the same time, the outlet of the liquid outlet pipe at position b discharges the liquid into the waste liquid pool b; after the liquid passing is completed, the device returns to the separation state.

[0100] ③ The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches position c, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact closed state; the inlet of the liquid supply pipe at position c passes the cleaning liquid Lc into the first extraction column, and its flow rate is controlled to be vc and the liquid passing time is tc. At the same time, the outlet of the liquid outlet pipe at position c discharges the liquid into the waste liquid pool c; after the liquid passing is completed, the device returns to the separation state.

[0101] ④ The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches position d, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact closed state; the inlet of the liquid supply pipe at position d passes the eluent Ld into the first extraction column, and its flow rate is controlled to be vd and the liquid passing time is td. At the same time, the outlet of the liquid outlet pipe at position d discharges the liquid into the collector d to obtain the quantum dot product; after the liquid passing is completed, the device returns to the separation state.

[0102] ⑤ The fixed flange rotates clockwise under the drive of the first driving unit 12, so that the first extraction column reaches position e, and is driven by the second driving unit 13. The liquid supply pipe, the first extraction column, and the liquid outlet pipe are in a contact closed state; the inlet of the liquid supply pipe at position e passes the regeneration liquid Le into the first extraction column, and its flow rate is controlled to be ve and the liquid passing time is te. At the same time, the outlet of the liquid outlet pipe at position e discharges the liquid into the waste liquid pool e; after the liquid passing is completed, the device returns to the separation state.

[0103] ⑥ The fixed flange is driven by the first driving unit 12 to rotate clockwise, so that the first extraction column returns to position a and undergoes the above process again.

[0104] While the first extraction column at the initial position a is sequentially undergoing the above steps, the extraction columns at the initial positions b, c, d, and e are also sequentially undergoing the above steps, except that at the same time point, the extraction columns are in different steps in real time. Among them, ta, tc, td, te, are all not greater than tb.

[0105] When the quantum dot purification unit is running, a total of 5 extraction columns perform solid phase extraction simultaneously and in sequence. The first drive unit 12 rotates very fast, far exceeding the speed of the inflow of the synthesized quantum dot product, realizing the continuous solid phase extraction purification of a large number of samples to be processed and the continuous collection of the processed samples. In addition, the rotation of the first drive unit 12, the control of the liquid supply unit 9 and the liquid outlet unit 11, and the control of the contact state and the separation state are all completed by program control. The operator only needs to set the relevant parameters before starting the operation, and no operation is required during the operation, that is, the entire process is fully automated.

[0106] Example 1

[0107] Preparation of precursors

[0108] Step 1: Add the raw materials (cadmium oxide, oleic acid, octadecene) required for preparing the cadmium precursor solution into the first reaction chamber 1-1-1 and the second reaction chamber 1-1-2 of the first reactor respectively, close the solenoid valve, set the target temperature of 250°C, the insulation time of 2h, and the stirring speed of 100r / min on the control panel, run the program, and the cadmium precursor can be obtained after the program ends.

[0109] Step 2: Add the raw materials (selenium, tri-n-octylphosphine, octadecene) required for preparing the selenium precursor solution into the first reaction chamber 1-2-1 and the second reaction chamber 1-2-2 of the second reactor respectively, close the solenoid valve, set the target temperature to 30°C, the insulation time to 2h, and the stirring speed to 100r / min on the control panel, run the program, and the selenium precursor can be obtained after the program ends.

[0110] CdSe Quantum Dot Synthesis

[0111] The precursor is transported to the quantum dot synthesis unit 3 via the precursor transport unit 2, the oil bath temperature is set to 283°C, and the flow rates of the anion and cation precursors are set to 2550 μL / min respectively; after about 1 minute, quantum dots are produced, and the absorption peak of the sample monitored by the spectrometer is 506 nm.

[0112] Afterwards, online and continuous purification is carried out through the quantum dot purification section, wherein the five liquid supply pipes in the liquid supply unit are respectively introduced with pretreatment liquid (methanol), synthesized quantum dots, cleaning liquid (ethanol), eluent (n-hexane), and regeneration liquid (a mixture of methanol and n-hexane, the volume fraction ratio of which can be 1:1).

[0113] Example 2

[0114] Preparation of precursors

[0115] The precursor was obtained in the same manner as in Example 1.

[0116] CdSe Quantum Dot Synthesis

[0117] The oil bath temperature was set to 282°C, and the flow rates of the anion and cation precursors were set to 1200 μL / min, respectively; after about 3 minutes, quantum dots were produced, and online spectral monitoring showed that the absorption peak of the sample was 577 nm.

[0118] 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.

[0119] 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 terms used herein are selected 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 quantum dot online production system, characterized in that: The quantum dot online production system comprises: a quantum dot synthesis section and a quantum dot purification section; The quantum dot synthesis unit comprises: a precursor reaction unit (1); a precursor delivery unit (2); a quantum dot synthesis unit (3); an online monitoring unit (4); and a product collection unit (5); the precursor reaction unit (1), the precursor delivery unit (2), the quantum dot synthesis unit (3) and the product collection unit (5) are sequentially connected, and the online monitoring unit (4) is located between the quantum dot synthesis unit (3) and the product collection unit (5); The quantum dot purification unit comprises: an extraction unit (10), a liquid supply unit (9), a first drive unit (12) and a liquid outlet unit (11). Wherein, the extraction unit (10) comprises a plurality of extraction columns; The liquid supply unit (9) comprises a plurality of liquid supply pipes for supplying reagents for each purification stage to the extraction column, and one of the liquid supply pipes is used to communicate with the product collection unit (5) and supply the collected product to the extraction column; Wherein, the liquid outlet unit (11) comprises a plurality of liquid outlet pipes for discharging the liquid produced in each purification stage; The first driving unit (12) is used to drive the extraction unit (10) to rotate so that the extraction columns can be connected to the liquid supply pipes at different positions at different times, so that the plurality of extraction columns are respectively in different purification stages.

2. The quantum dot online production system according to claim 1, characterized in that: The quantum dot purification section comprises two second driving units (13), which are respectively connected to the liquid supply unit (9) and the liquid outlet unit (11), and are used to respectively drive the liquid supply pipe in the liquid supply unit (9) and the liquid outlet pipe in the liquid outlet unit (11) to connect with and disconnect from the extraction column.

3. The quantum dot online production system according to claim 1 or 2, characterized in that: The extraction column is provided with a solid phase unit, which includes basic microspheres whose surfaces are made of glass and silane containing alkoxy groups and alkyl groups with carbon atoms of 6-36 grafted on the surfaces of the basic microspheres.

4. The quantum dot online production system according to any one of claims 1 to 3, characterized in that: The precursor reaction unit (1) comprises at least a first reactor (1-1) and a second reactor (1-2), wherein the first reactor (1-1) and / or the second reactor (1-2) respectively comprise more than two reaction chambers, and the first reactor (1-1) and the second reactor (1-2) are respectively connected to the precursor delivery unit (2) via a switching device.

5. The quantum dot online production system according to any one of claims 1 to 4, characterized in that: The precursor delivery unit (2) comprises a flow controller.

6. The quantum dot online production system according to any one of claims 1 to 5, characterized in that: The quantum dot synthesis unit (3) comprises a pipeline for allowing the precursor to pass through, the quantum dot synthesis unit (3) comprises a pressurizer and / or a magnetizer, the quantum dot synthesis unit (3) comprises an oil bath heater, or a sand bath heater, or an electric heater or a magnetic thermal heater; and / or, The quantum dot synthesis unit (3) comprises at least one reaction zone, and the reaction conditions of each reaction zone are independently controlled.

7. The quantum dot online production system according to any one of claims 1 to 6, characterized in that: The online monitoring unit (4) comprises a spectrum analyzer and / or a nuclear magnetic analyzer, wherein the spectrum analyzer is capable of monitoring at least one of the emission peak position, half-peak width, absorption intensity, trough position, and quantum dot yield of the quantum dots, and the nuclear magnetic analyzer is used to analyze the hydrogen spectrum of the quantum dots.

8. The quantum dot online production system according to any one of claims 1 to 7, characterized in that: The product collection unit (5) comprises a liquid storage portion, the liquid storage portion comprises one or more liquid reservoirs, and the liquid reservoirs comprise liquid level sensors.

9. The quantum dot online production system according to claim 8, characterized in that: The extraction column comprises an inlet capable of communicating with a liquid outlet of a liquid supply pipe and an outlet capable of communicating with a liquid inlet of a liquid outlet pipe. The liquid outlet of the liquid supply pipe and / or the liquid inlet of the liquid outlet pipe both comprise a conical guide port (14) and a sealing ring (15).

10. A method for producing quantum dots, characterized in that: The quantum dots are produced by using the quantum dot online production system described in any one of claims 1 to 9.

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