A preparation method and production equipment of perovskite quantum dots and their composites

Through solid phase sintering method and optimized reaction equipment, the industrial mass production and environmental pollution of perovskite quantum dots are solved, and efficient perovskite quantum dot preparation is achieved.

CN119951418BActive Publication Date: 2025-08-08LONGYAN UNIV
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Patent Information

Application Number
CN202510432120.7
Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Filing Date
2025-04-08
Publication Date
2025-08-08
Estimated Expiration
2045-04-08

AI Technical Summary

Technical Problem

The preparation method of perovskite quantum dots in the prior art cannot achieve industrial mass production, and the traditional heat injection method has difficulties in environmental pollution and grain size control.

Method used

The solid phase sintering method is used, AlO(OH) is used as the matrix, and the reaction process is optimized through the material lifting mechanism, the driving mechanism and the cooling mechanism to ensure that CsPbX3 does not grow up at high temperatures and form a dry solid powder.

Benefits of technology

The industrial mass production of perovskite quantum dots is realized, which avoids environmental pollution, maintains the quantum bound domain effect, and improves the reaction efficiency and production process.

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Abstract

The present invention discloses a method and production equipment for preparing perovskite quantum dots and their composites, relating to the technical field of preparing perovskite quantum dots and their composites. The method comprises a reactor; a material lifting mechanism, the material lifting mechanism comprising an annular groove formed on the inner wall of the reactor, the inner wall of the annular groove being symmetrically and slidably connected to two mounting brackets, the inner walls of the two mounting brackets being rotatably connected to a first rod, the side walls of the first rods being fixedly connected to a lifting plate, and the inner wall of the reactor being symmetrically and fixedly connected to two limiting rods, the side walls of the two limiting rods being slidably connected to a slider. The present invention utilizes a solid-phase sintering method, which, compared to the traditional hot injection method, allows for industrial mass production. Furthermore, AlO(OH) is used as a matrix. At high temperatures, AlO(OH) is limited by its own pore size, preventing the size of CsPbX3 from growing with increasing temperature, thereby retaining the quantum confinement effect. Furthermore, the method does not require the participation of surface ligands, and can synthesize dry solid powders, reducing environmental hazards.
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Description

Technical Field

[0001] The present invention relates to the technical field of preparation of perovskite quantum dots and their composites, and in particular to a preparation method and production equipment of perovskite quantum dots and their composites. Background Art

[0002] In recent years, quantum dot materials have been applied in the field of flat panel displays due to their unique advantages of high color saturation corresponding to narrow emission spectra, which can significantly improve the color display range of display devices.

[0003] Currently, perovskite quantum dots and their composites are prepared by hot injection. However, the perovskite quantum dots synthesized by the traditional hot injection method cannot be dried into solid powder due to the presence of environmentally harmful surface oily ligands, which will pollute the environment. Moreover, the experimental operation is cumbersome. The participation of condensed water, three-necked flask, and nitrogen makes this method only suitable for small-scale laboratory-level production and not for industrial mass production, which seriously limits its practical application. In addition, due to the quantum confinement effect of perovskite quantum dots, the increase in sintering temperature will cause the CsPbX3 grain size to grow uncontrollably.

[0004] Based on this, we propose a preparation method and production equipment for perovskite quantum dots and their composites. Summary of the Invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a method and production equipment for preparing perovskite quantum dots and their composites.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for preparing perovskite quantum dots and their composites comprises the following steps:

[0008] S1. First, weigh appropriate amounts of CsBr, PbBr2, and AlO(OH) according to the ratio. The ratio of (CsBr: PbBr2) and AlO(OH) is 0.082 mmol and 2.46 mmol respectively.

[0009] S2. Grind the weighed CsBr, PbBr2 and AlO(OH) into powder for 30 min to fully mix them;

[0010] S3. Then, the powdered CsBr, PbBr2 and AlO(OH) are placed in the equipment for sintering. The sintering temperature is controlled at 650 degrees Celsius, and nitrogen is introduced for protection during the sintering process.

[0011] S4. After sintering, perovskite quantum dots in the form of blue, green and red quantum dot powders can be obtained.

[0012] A production device for perovskite quantum dots and their composites, comprising:

[0013] reactor;

[0014] The lifting mechanism comprises an annular groove provided on the inner wall of the reactor, the inner wall of the annular groove is symmetrically and slidably connected to two mounting brackets, the inner walls of the two mounting brackets are rotatably connected to a first rod, the side wall of the first rod is fixedly connected to a lifting plate, the inner wall of the reactor is symmetrically and fixedly connected to two limit rods, the side walls of the two limit rods are commonly slidably connected to a slider, the side wall of the slider is provided with a limiting groove, the inner wall of the limiting groove is symmetrically and slidably connected to two L-shaped rods, the other ends of the two L-shaped rods are fixedly connected to the mounting rods, the side walls of the mounting rods are symmetrically and fixedly connected to the two L-shaped brackets, the side walls of the lifting plate are fixedly connected to the second rod, the side walls of the two L-shaped brackets are provided with two sliding grooves, and the side walls of the second rod are slidably connected to the inner walls of the two sliding grooves;

[0015] A driving mechanism is installed on the reaction furnace.

[0016] Preferably, the driving mechanism includes a rotating shaft rotatably connected to the top of the reactor, a reciprocating screw is fixedly connected to the lower end of the rotating shaft, the side wall of the reciprocating screw is threadedly connected to the slider, the upper end of the reactor is fixedly connected to the motor, and the output end of the motor passes through the upper end of the reactor and is fixedly connected to the rotating shaft.

[0017] Preferably, the driving mechanism also includes two driving rods symmetrically fixedly connected to the side walls of the reciprocating screw, the lower ends of the two driving rods are respectively fixedly connected to the upper ends of the two mounting frames, the side walls of the mounting rods are provided with vertical grooves, the vertical grooves pass through the side walls of the mounting rods, and the side walls of the driving rods are slidably connected to the inner walls of the vertical grooves.

[0018] Preferably, the lower ends of the two mounting frames are fixedly connected to two fixing rods, the other ends of the two fixing rods are commonly fixedly connected to an annular cover, and the lower end of the annular cover is arranged to fit the bottom of the reactor.

[0019] Preferably, a material gathering mechanism is installed on the annular cover, and the material gathering mechanism includes two T-shaped rods symmetrically and slidingly connected to the side wall of the annular cover, one end of each of the two T-shaped rods passes through the inner wall of the annular cover and is fixedly connected to a push plate, the side wall of the lifting plate is fixedly connected to a fixing frame, the upper end of the T-shaped rod is fixedly connected to a third rod, the side wall of the fixing frame is rotatably connected to a connecting rod, and the other end of the connecting rod is rotatably connected to the third rod.

[0020] Preferably, a mounting groove is provided in the top of the reaction furnace, and a plurality of fan blades are fixedly connected to the side wall of the rotating shaft located in the mounting groove.

[0021] Preferably, a first annular cavity is provided in the reaction furnace, a plurality of first exhaust holes are provided at the bottom of the first annular cavity, one end of the first exhaust hole is connected to the mounting groove, a first solenoid valve is installed on the inner wall of the first exhaust hole, an air supply pipe is fixedly connected to the inner wall of the first annular cavity, and the other end of the air supply pipe is connected to an external air pump.

[0022] Preferably, the reactor is provided with a cooling mechanism, the cooling mechanism comprising a second annular cavity provided in the reactor, two second exhaust holes provided in the bottom of the second annular cavity, the other end of the second exhaust hole being connected to the mounting groove, a pressure relief valve being installed on the inner wall of the second exhaust hole, the first annular cavity being connected to the second annular cavity through a plurality of one-way air inlet holes, a second solenoid valve being installed on the inner wall of the one-way air inlet hole, an installation cavity provided in the side wall of the reactor, a temperature sensor being installed on the inner wall of the installation cavity, and the temperature sensor being connected to the first solenoid valve and the second solenoid valve through a PLC control circuit.

[0023] Preferably, a feed pipe is fixedly connected to the upper end of the reaction furnace, a discharge pipe is fixedly connected to the lower end of the reaction furnace, and a valve is installed at the lower end of the discharge pipe.

[0024] The present invention has the following beneficial effects:

[0025] 1. Compared with the traditional hot injection method, the solid-phase sintering method can be used for industrial mass production. In addition, AlO (OH) is used as the matrix. At high temperatures, due to the limitation of the pore size of AlO (OH), the size of CsPbX3 cannot grow with increasing temperature, retaining the quantum confinement effect. In addition, the participation of surface ligands is not required, and dry solid powder can be synthesized, reducing the harm to the environment.

[0026] 2. By setting up a lifting mechanism and a driving mechanism, during the reaction process, as the sintering temperature increases, the CsBr and PbBr2 materials melt and vaporize to become gaseous CsBr and PbBr2, and the gaseous CsBr and PbBr2 will flow upward in the reactor, and then the AlO (OH) at the bottom will not be able to fully contact with the gaseous CsBr and PbBr2, and then CsBr and PbBr2 will not be well distributed in the pores of AlO (OH) to form perovskite quantum dots. Therefore, during the sintering process, the motor is started so that the lifting plate can shovel up the AlO (OH) at the bottom of the reactor and then lift it to the middle position of the reactor, so that AlO (OH) can fully contact with the gaseous CsBr and PbBr2, so that the gaseous CsBr and PbBr2 are distributed in the pores of AlO (OH) to form perovskite quantum dots;

[0027] 3. When the reciprocating screw rotates, it will synchronously drive the two mounting frames to rotate through the two driving rods, and then drive the two lifting plates to make circular motion, thereby lifting AlO (OH) at different positions, maximizing the contact between all AlO (OH) and CsBr and PbBr2, so that the reaction is more complete and no waste is caused;

[0028] 4. By setting up a material gathering mechanism, the lifting plate will drive the fixed frame to rotate repeatedly when it rotates repeatedly, and then the fixed frame will drive the T-bar to move back and forth through the connecting rod and the third rod, thereby driving the push plate to move back and forth. When the lifting plate rotates away from the inner wall of the reactor, the push plate will move toward the center of the reactor, and then push the AlO (OH) at the edge of the annular cover into the center of the reactor for accumulation. At this time, the lifting plate can scoop up more AlO (OH), and each time more AlO (OH) will come into contact with the gaseous CsBr and PbBr2, thereby improving the reaction efficiency and accelerating the production process.

[0029] 5. By setting the mounting slots and fan blades, the rotating shaft will drive multiple fan blades to rotate. Under the action of the fan blades, on the one hand, the nitrogen discharged through the first exhaust hole can flow downward quickly and contact with the lower material, forming a protective and air-isolating effect. On the other hand, when the nitrogen flows downward, it can effectively inhibit the upward flow of gaseous CsBr and PbBr2, so that the gaseous CsBr and PbBr2 stay in the middle and lower part of the reactor as much as possible. Cooperating with the lifting plate, AlO (OH) can fully contact with more CsBr and PbBr2 as much as possible.

[0030] 6. By setting a cooling mechanism, when the temperature in the reactor 1 exceeds 650 degrees Celsius, the temperature sensor will sense a signal, and the first solenoid valve and the second solenoid valve will be energized through the PLC control circuit. The first solenoid valve will be energized to close, and the second solenoid valve will be energized to open. Then, the nitrogen entering the first annular cavity will enter the second annular cavity through the one-way air inlet hole. The nitrogen will accumulate in the second annular cavity, and the pressure in the second annular cavity will gradually increase. Then, the nitrogen will gradually increase in pressure. When the pressure in the second annular cavity exceeds the threshold of the pressure relief valve, the pressure relief valve will open, and the nitrogen will instantly enter the reactor through the second exhaust hole. According to the principle of nitrogen expansion refrigeration, nitrogen is released after being pressurized. Its pressure will decrease during the expansion process, and then the change in molecular energy will cause the temperature to drop. Therefore, the nitrogen released after pressurization can serve the purpose of refrigeration and reduce the temperature in the reactor. When the temperature drops to 650 degrees Celsius, the temperature sensor will cut off the power supply through the PLC control circuit, and then the first solenoid valve will be de-energized and opened, and the second solenoid valve will be de-energized and closed, thereby ensuring normal nitrogen supply. Therefore, the temperature can be automatically lowered according to the temperature changes in the reactor, so that the temperature in the reactor is always maintained at the optimal reaction temperature of around 650 degrees Celsius. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the three-dimensional structure of a perovskite quantum dot and composite production device proposed by the present invention;

[0032] Figure 2 for Figure 1 Schematic cross-sectional view of the structure;

[0033] Figure 3 for Figure 2 Structural diagram of the middle lifting mechanism;

[0034] Figure 4 for Figure 2 A schematic diagram of the structure enlargement at point A;

[0035] Figure 5 for Figure 2 A magnified schematic diagram of the structure at point B in FIG.

[0036] Figure 6 for Figure 2 Schematic diagram of the enlarged structure at point C in FIG.

[0037] In the figure: 1, reactor; 2, annular groove; 3, mounting frame; 4, first rod; 5, lifting plate; 6, limiting rod; 7, slider; 8, limiting groove; 9, L-shaped rod; 10, mounting rod; 11, L-shaped frame; 12, second rod; 13, slide; 14, rotating shaft; 15, reciprocating screw; 16, motor; 17, annular cover; 18, T-shaped rod; 19, push plate; 20, fixing rod; 21, fixing frame; 22, third Rod; 23. Connecting rod; 24. First annular cavity; 25. First exhaust hole; 26. First solenoid valve; 27. Air supply pipe; 28. Mounting slot; 29. Fan blade; 30. Second annular cavity; 31. Second exhaust hole; 32. Pressure relief valve; 33. One-way air inlet hole; 34. Second solenoid valve; 35. Mounting cavity; 36. Temperature sensor; 37. Feed pipe; 38. Discharge pipe; 39. Drive rod; 40. Vertical slot. DETAILED DESCRIPTION

[0038] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0039] A method for preparing perovskite quantum dots and their composites comprises the following steps:

[0040] S1. First, weigh appropriate amounts of CsBr, PbBr2, and AlO(OH) according to the ratio. The ratio of (CsBr: PbBr2) and AlO(OH) is 0.082 mmol and 2.46 mmol respectively.

[0041] S2. Grind the weighed CsBr, PbBr2 and AlO(OH) into powder for 30 min to fully mix them;

[0042] S3. Then, the powdered CsBr, PbBr2 and AlO(OH) are placed in the equipment for sintering. The sintering temperature is controlled at 650 degrees Celsius, and nitrogen is introduced for protection during the sintering process.

[0043] S4. After sintering, perovskite quantum dots in the form of blue, green and red quantum dot powders can be obtained.

[0044] Reference Figure 1 - Figure 6 , a production device for perovskite quantum dots and their composites, comprising:

[0045] Reactor 1;

[0046] Lifting mechanism, such as Figure 2 - Figure 3 As shown, the lifting mechanism includes an annular groove 2 provided on the inner wall of the reactor 1, two mounting brackets 3 are symmetrically and slidably connected to the inner wall of the annular groove 2, the inner walls of the two mounting brackets 3 are rotatably connected to the first rod 4, the side walls of the first rod 4 are fixedly connected to the lifting plate 5, the inner wall of the reactor 1 is symmetrically and fixedly connected to two limiting rods 6, the side walls of the two limiting rods 6 are commonly slidably connected to a slider 7, the side wall of the slider 7 is provided with a limiting groove 8, the inner wall of the limiting groove 8 is symmetrically and slidably connected to two L-shaped rods 9, the other ends of the two L-shaped rods 9 are fixedly connected to the mounting rod 10, the side wall of the mounting rod 10 is symmetrically and fixedly connected to two L-shaped brackets 11, the side wall of the lifting plate 5 is fixedly connected to the second rod 12, the side walls of the two L-shaped brackets 11 are provided with two sliding grooves 13, and the side wall of the second rod 12 is slidably connected to the inner walls of the two sliding grooves 13;

[0047] A driving mechanism is installed on the reaction furnace 1 .

[0048] like Figure 2 As shown, the driving mechanism includes a rotating shaft 14 rotatably connected to the top of the reactor 1, a reciprocating screw 15 is fixedly connected to the lower end of the rotating shaft 14, and the side wall of the reciprocating screw 15 is threadedly connected to the slider 7. A motor 16 is fixedly connected to the upper end of the reactor 1, and the output end of the motor 16 passes through the upper end of the reactor 1 and is fixedly connected to the rotating shaft 14.

[0049] Furthermore, during the reaction process, as the sintering temperature increases, the CsBr and PbBr2 materials melt and gasify to become gaseous CsBr and PbBr2, and the gaseous CsBr and PbBr2 will flow upward in the reactor 1, and the AlO (OH) at the bottom will not be able to fully contact with the gaseous CsBr and PbBr2, and CsBr and PbBr2 will not be able to be well dispersed in the pores of AlO (OH) to form perovskite quantum dots. Therefore, during the sintering process, the motor 16 is started to drive the shaft 14 to rotate, and at this time the rotation of the shaft 14 will synchronously drive The reciprocating screw 15 rotates, and the slider 7 slides back and forth quickly up and down. The slider 7 drives the mounting rod 10 to move back and forth up and down through the L-shaped rod 9, and then drives the L-shaped frame 11 to move back and forth up and down, thereby driving the lifting plate 5 to rotate back and forth with the center of the first rod 4 as the center of the circle. Then, the lifting plate 5 can scoop up the AlO (OH) at the bottom of the reactor 1, and then lift it to the middle position of the reactor 1, so that the AlO (OH) can fully contact with the gaseous CsBr and PbBr2, so that the gaseous CsBr and PbBr2 are dispersed in the pores of the AlO (OH), forming perovskite quantum dots.

[0050] like Figure 2 - Figure 3 As shown, the driving mechanism also includes two driving rods 39 symmetrically fixedly connected to the side walls of the reciprocating screw 15, the lower ends of the two driving rods 39 are respectively fixedly connected to the upper ends of the two mounting frames 3, and a vertical groove 40 is provided on the side wall of the mounting rod 10. The vertical groove 40 passes through the side wall of the mounting rod 10, and the side wall of the driving rod 39 is slidably connected to the inner wall of the vertical groove 40.

[0051] Furthermore, when the reciprocating screw 15 rotates, the two mounting frames 3 are synchronously driven to rotate through the two driving rods 39, thereby driving the two lifting plates 5 to perform circular motion, thereby lifting AlO (OH) at different positions, maximizing the contact between all AlO (OH) and CsBr and PbBr2, thereby making the reaction more complete and causing no waste.

[0052] The lower ends of the two mounting frames 3 are fixedly connected to two fixing rods 20 , and the other ends of the two fixing rods 20 are commonly fixedly connected to an annular cover 17 , and the lower end of the annular cover 17 is arranged in contact with the bottom of the reactor 1 .

[0053] like Figure 2 and Figure 5As shown, a material gathering mechanism is installed on the annular cover 17, and the material gathering mechanism includes two T-shaped rods 18 symmetrically slidably connected to the side wall of the annular cover 17, one end of the two T-shaped rods 18 passes through the inner wall of the annular cover 17 and is fixedly connected to a push plate 19, the side wall of the lifting plate 5 is fixedly connected to a fixing frame 21, the upper end of the T-shaped rod 18 is fixedly connected to a third rod 22, the side wall of the fixing frame 21 is rotatably connected to a connecting rod 23, and the other end of the connecting rod 23 is rotatably connected to the third rod 22.

[0054] Furthermore, when the lifting plate 5 rotates repeatedly, it will drive the fixed frame 21 to rotate repeatedly, and then the fixed frame 21 will drive the T-shaped rod 18 to move back and forth through the connecting rod 23 and the third rod 22, thereby driving the push plate 19 to move back and forth. When the lifting plate 5 rotates in a direction away from the inner wall of the reactor 1, the push plate 19 will move toward the center of the reactor 1, and then push the AlO (OH) at the edge of the annular cover 17 into the center of the reactor 1 for accumulation. At this time, the lifting plate 5 can scoop up more AlO (OH), and each time more AlO (OH) will come into contact with the gaseous CsBr and PbBr2, thereby improving the efficiency of the reaction and accelerating the production process.

[0055] like Figure 2 and Figure 6 As shown, a mounting groove 28 is provided on the top of the reaction furnace 1 , and a plurality of fan blades 29 are fixedly connected to the side wall of the rotating shaft 14 located in the mounting groove 28 .

[0056] Furthermore, the rotating shaft 14 drives the plurality of fan blades 29 to rotate. Under the action of the fan blades 29, on the one hand, the nitrogen discharged through the first exhaust hole 25 can flow downward quickly and contact the lower material, forming a protective and air-isolating effect. On the other hand, when the nitrogen flows downward, it can effectively inhibit the upward flow of gaseous CsBr and PbBr2, so that the gaseous CsBr and PbBr2 stay as much as possible in the middle and lower part of the reactor 1, and cooperate with the lifting plate 5 to allow AlO (OH) to fully contact with more CsBr and PbBr2 as much as possible.

[0057] like Figure 2 and Figure 6 As shown, a first annular cavity 24 is provided in the reactor 1, and a plurality of first exhaust holes 25 are provided at the bottom of the first annular cavity 24. One end of the first exhaust hole 25 is connected to the mounting groove 28. A first solenoid valve 26 is installed on the inner wall of the first exhaust hole 25. The first solenoid valve 26 is closed when powered on and opened when powered off. An air supply pipe 27 is fixedly connected to the inner wall of the first annular cavity 24, and the other end of the air supply pipe 27 is connected to an external air pump.

[0058] Furthermore, during the sintering process, the external air pump is started to pump nitrogen into the first annular cavity 24 through the air supply pipe 27, and then the nitrogen enters the reactor 1 through the multiple first exhaust holes 25 to protect and isolate the air.

[0059] The reaction furnace 1 is equipped with a cooling mechanism, such as Figure 2 and Figure 6 As shown, the cooling mechanism includes a second annular cavity 30 provided in the reactor 1, two second exhaust holes 31 are provided at the bottom of the second annular cavity 30, the other end of the second exhaust hole 31 is connected to the mounting groove 28, and a pressure relief valve 32 is installed on the inner wall of the second exhaust hole 31. The first annular cavity 24 is connected to the second annular cavity 30 through a plurality of one-way air inlet holes 33. The one-way air inlet holes 33 only allow nitrogen in the first annular cavity 24 to enter the second annular cavity 30. A second solenoid valve 34 is installed on the inner wall of the one-way air inlet hole 33. The second solenoid valve 34 is opened when power is turned on and closed when power is turned off. An installation cavity 35 is provided in the side wall of the reactor 1, and a temperature sensor 36 is installed on the inner wall of the installation cavity 35. The temperature sensor 36 is connected to the first solenoid valve 26 and the second solenoid valve 34 through a PLC control circuit.

[0060] Furthermore, when the temperature in the reactor 1 exceeds 650 degrees Celsius, the temperature sensor 36 will sense a signal and energize the first solenoid valve 26 and the second solenoid valve 34 through the PLC control circuit. The first solenoid valve 26 is energized to close, and the second solenoid valve 34 is energized to open. Then, the nitrogen entering the first annular cavity 24 will enter the second annular cavity 30 through the one-way air inlet 33. The nitrogen will accumulate in the second annular cavity 30, and the pressure in the second annular cavity 30 will gradually increase. Then, the nitrogen will gradually be pressurized. When the pressure in the second annular cavity 30 exceeds the threshold of the pressure relief valve 32, the pressure relief valve 32 will open, and the nitrogen will instantly pass through the second exhaust hole 31. After entering the reactor 1, according to the nitrogen expansion refrigeration principle, the nitrogen is released after being pressurized. The pressure will decrease during the expansion process, and then the molecular energy change causes the temperature to drop. Therefore, the nitrogen released after pressurization can serve the purpose of refrigeration and can reduce the temperature in the reactor 1. When the temperature drops to 650 degrees Celsius, the temperature sensor 36 will cut off the power supply through the PLC control circuit, and then the first solenoid valve 26 will be de-energized and opened, and the second solenoid valve 34 will be de-energized and closed, thereby ensuring normal nitrogen supply. Therefore, the temperature can be automatically lowered according to the temperature change in the reactor 1, so that the temperature in the reactor 1 is always maintained at the optimal reaction temperature of about 650 degrees Celsius.

[0061] like Figure 2 As shown, a feed pipe 37 is fixedly connected to the upper end of the reaction furnace 1 , a discharge pipe 38 is fixedly connected to the lower end of the reaction furnace 1 , and a valve is installed at the lower end of the discharge pipe 38 .

[0062] In the present invention, first, the materials are measured according to the feeding ratio of (CsBr: PbBr2) and AlO (OH) of 0.082 mmol and 2.46 mmol, and then the materials are ground into powder and added into the reactor 1 through the feed pipe 37. The reactor 1 is started and the materials are sintered at a high temperature. The sintering temperature is controlled at 650 degrees Celsius.

[0063] During the sintering process, the external air pump is started to pump nitrogen into the first annular cavity 24 through the air supply pipe 27. The nitrogen then enters the reactor 1 through the multiple first exhaust holes 25 to protect and isolate the air.

[0064] During the reaction process, as the sintering temperature increases, the CsBr and PbBr2 materials melt and vaporize to become gaseous CsBr and PbBr2, and the gaseous CsBr and PbBr2 will flow upward in the reactor 1, and the AlO (OH) at the bottom will not be able to fully contact with the gaseous CsBr and PbBr2, and CsBr and PbBr2 will not be able to be well dispersed in the pores of AlO (OH) to form perovskite quantum dots. Therefore, during the sintering process, the motor 16 is started to drive the rotating shaft 14 to rotate, and the rotating shaft 14 will drive the multiple fan blades 29 to rotate. Under the action of the fan blades 29, on the one hand, the nitrogen discharged through the first exhaust hole 25 can flow downward quickly and contact with the lower material to form a protective air isolation effect. On the other hand, when the nitrogen flows downward, it can be well The upward flow of gaseous CsBr and PbBr2 is suppressed, so that the gaseous CsBr and PbBr2 stay in the middle and lower part of the reactor 1 as much as possible, and at this time, the rotation of the rotating shaft 14 will synchronously drive the reciprocating screw 15 to rotate, and then the slider 7 will slide back and forth quickly up and down, and the slider 7 will drive the mounting rod 10 to move back and forth up and down through the L-shaped rod 9, and then drive the L-shaped frame 11 to move back and forth up and down, thereby driving the lifting plate 5 to rotate back and forth with the center of the first rod 4 as the center of the circle, and then the lifting plate 5 can scoop up the AlO (OH) at the bottom of the reactor 1, and then lift it to the middle position of the reactor 1, and then AlO (OH) can fully contact with the gaseous CsBr and PbBr2, so that the gaseous CsBr and PbBr2 are dispersed in the pores of AlO (OH), forming perovskite quantum dots.

[0065] When the lifting plate 5 rotates repeatedly, it will drive the fixed frame 21 to rotate repeatedly, and then the fixed frame 21 will drive the T-shaped rod 18 to move back and forth through the connecting rod 23 and the third rod 22, thereby driving the push plate 19 to move back and forth. When the lifting plate 5 rotates in a direction away from the inner wall of the reactor 1, the push plate 19 will move toward the center of the reactor 1, and then push the AlO (OH) at the edge of the annular cover 17 into the center of the reactor 1 for accumulation. At this time, the lifting plate 5 can scoop up more AlO (OH), and each time more AlO (OH) will come into contact with the gaseous CsBr and PbBr2, thereby improving the reaction efficiency and accelerating the production process.

[0066] When the reciprocating screw 15 rotates, it will synchronously drive the two mounting frames 3 to rotate through the two driving rods 39, and then drive the two lifting plates 5 to make circular motion, so that AlO (OH) at different positions can be lifted, so that all AlO (OH) can contact with CsBr and PbBr2 to the maximum extent, so that the reaction is more complete and no waste is caused. When the mounting frame 3 rotates, it will drive the annular cover 17 to rotate synchronously through the fixed rod 20, and then the push plate 19 will also rotate synchronously to maintain the aggregation of AlO (OH) at the bottom.

[0067] When the temperature in the reactor 1 exceeds 650 degrees Celsius, the temperature sensor 36 will sense a signal and energize the first solenoid valve 26 and the second solenoid valve 34 through the PLC control circuit. The first solenoid valve 26 is energized to close, and the second solenoid valve 34 is energized to open. Then, the nitrogen entering the first annular cavity 24 will enter the second annular cavity 30 through the one-way air inlet 33. The nitrogen will accumulate in the second annular cavity 30, and the pressure in the second annular cavity 30 will gradually increase. Then, the nitrogen will gradually increase in pressure. When the pressure in the second annular cavity 30 exceeds the threshold of the pressure relief valve 32, the pressure relief valve 32 will open, and the nitrogen will instantly enter through the second exhaust hole 31. In the reactor 1, according to the nitrogen expansion refrigeration principle, the nitrogen is released after being pressurized, and its pressure will decrease during the expansion process, and then the molecular energy change causes the temperature to drop. Therefore, the nitrogen released after pressurization can serve the purpose of refrigeration and can reduce the temperature in the reactor 1. When the temperature drops to 650 degrees Celsius, the temperature sensor 36 will cut off the power supply through the PLC control circuit, and then the first solenoid valve 26 will be de-energized and opened, and the second solenoid valve 34 will be de-energized and closed, thereby carrying out normal nitrogen supply. Therefore, the temperature can be automatically lowered according to the temperature change in the reactor 1, so that the temperature in the reactor 1 is always maintained at the optimal reaction temperature of about 650 degrees Celsius.

[0068] After sintering is completed, the valve on the discharge pipe 38 is opened, and the obtained perovskite quantum dots of blue, green and red quantum dot powders are discharged through the discharge pipe 38 and collected.

[0069] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A production device for perovskite quantum dots and their composites, characterized in that: include: Reactor (1); A material lifting mechanism, the material lifting mechanism comprises an annular groove (2) provided on the inner wall of the reaction furnace (1), the inner wall of the annular groove (2) is symmetrically and slidably connected to two mounting frames (3), the inner walls of the two mounting frames (3) are both rotatably connected to a first rod (4), the side walls of the first rod (4) are fixedly connected to a lifting plate (5), the inner wall of the reaction furnace (1) is symmetrically and fixedly connected to two limiting rods (6), the side walls of the two limiting rods (6) are jointly and slidably connected to a slider (7), the side wall of the slider (7) is provided with a limiting groove (8), the inner wall of the limiting groove (8) is symmetrically and slidably connected to two L-shaped rods (9), the other ends of the two L-shaped rods (9) are both fixedly connected to a mounting rod (10), the side walls of the mounting rod (10) are symmetrically and slidably connected to two L-shaped frames (11), the side wall of the lifting plate (5) is fixedly connected to a second rod (12), the side walls of the two L-shaped frames (11) are provided with two sliding grooves (13), and the side wall of the second rod (12) is slidably connected to the inner walls of the two sliding grooves (13); A driving mechanism is installed on the reaction furnace (1); The driving mechanism comprises a rotating shaft (14) rotatably connected to the top of the reaction furnace (1), a reciprocating screw (15) fixedly connected to the lower end of the rotating shaft (14), a side wall of the reciprocating screw (15) being threadedly connected to the slider (7), a motor (16) fixedly connected to the upper end of the reaction furnace (1), an output end of the motor (16) passing through the upper end of the reaction furnace (1) and fixedly connected to the rotating shaft (14); The driving mechanism further comprises two driving rods (39) symmetrically fixedly connected to the side walls of the reciprocating screw (15), the lower ends of the two driving rods (39) being fixedly connected to the upper ends of the two mounting frames (3) respectively, the side walls of the mounting rod (10) being provided with a vertical groove (40), the vertical groove (40) being arranged through the side walls of the mounting rod (10), and the side walls of the driving rod (39) being slidably connected to the inner walls of the vertical groove (40).

2. The production equipment of perovskite quantum dots and their composites according to claim 1, characterized in that: in: The lower ends of the two mounting frames (3) are fixedly connected to two fixing rods (20), and the other ends of the two fixing rods (20) are fixedly connected to an annular cover (17). The lower end of the annular cover (17) is arranged to fit the bottom of the reactor (1).

3. The production equipment of perovskite quantum dots and their composites according to claim 2, characterized in that: in: A material gathering mechanism is installed on the annular cover (17), and the material gathering mechanism includes two T-shaped rods (18) symmetrically slidably connected to the side wall of the annular cover (17), one end of each of the two T-shaped rods (18) passes through the inner wall of the annular cover (17) and is fixedly connected to a push plate (19), the side wall of the lifting plate (5) is fixedly connected to a fixing frame (21), the upper end of the T-shaped rod (18) is fixedly connected to a third rod (22), the side wall of the fixing frame (21) is rotatably connected to a connecting rod (23), and the other end of the connecting rod (23) is rotatably connected to the third rod (22).

4. The production equipment of perovskite quantum dots and their composites according to claim 1, characterized in that: in: A mounting groove (28) is provided on the top of the reaction furnace (1), and a plurality of fan blades (29) are fixedly connected to the side wall of the rotating shaft (14) located in the mounting groove (28).

5. The production equipment of perovskite quantum dots and their composites according to claim 4, characterized in that: in: A first annular cavity (24) is provided in the reaction furnace (1), a plurality of first exhaust holes (25) are provided at the bottom of the first annular cavity (24), one end of the first exhaust hole (25) is communicated with the mounting groove (28), a first solenoid valve (26) is installed on the inner wall of the first exhaust hole (25), an air supply pipe (27) is fixedly connected to the inner wall of the first annular cavity (24), and the other end of the air supply pipe (27) is communicated with an external air pump.

6. The production equipment of perovskite quantum dots and their composites according to claim 5, characterized in that: in: The reactor (1) is provided with a cooling mechanism, which comprises a second annular cavity (30) provided in the reactor (1), two second exhaust holes (31) provided at the bottom of the second annular cavity (30), the other end of the second exhaust hole (31) being in communication with the installation groove (28), a pressure relief valve (32) being provided on the inner wall of the second exhaust hole (31), the first annular cavity (24) being in communication with the second annular cavity (30) through a plurality of one-way air inlet holes (33), a second solenoid valve (34) being provided on the inner wall of the one-way air inlet hole (33), a mounting cavity (35) provided in the side wall of the reactor (1), a temperature sensor (36) being provided on the inner wall of the mounting cavity (35), the temperature sensor (36) being connected to the first solenoid valve (26) and the second solenoid valve (34) through a PLC control circuit.

7. The production equipment of perovskite quantum dots and their composites according to claim 1, characterized in that: in: The upper end of the reaction furnace (1) is fixedly connected to a feed pipe (37), the lower end of the reaction furnace (1) is fixedly connected to a discharge pipe (38), and a valve is installed at the lower end of the discharge pipe (38).

Citation Information

Patent Citations

  • Preparation method of perovskite quantum dot powder

    CN114479831A