Large-scale synthesis equipment and preparation method of rare earth nanometer luminescent material

Abstract

This invention discloses a large-scale synthesis equipment and preparation method for rare-earth luminescent nanomaterials, belonging to the field of rare-earth luminescent nanomaterial preparation technology. The large-scale synthesis equipment of this invention includes a main reactor, a stirring device, a reaction device, support legs, a feeding system, and a control system. This large-scale synthesis equipment integrates multiple parallel reaction units, centralized heating, and stirring. By constructing multiple parallel and equivalent small reaction units within the same main reactor and utilizing a unified thermal field and synchronous stirring mechanism, multiple liquid-phase reaction systems simultaneously complete nucleation, growth, and phase transformation processes under highly consistent reaction kinetics. This achieves stable large-scale preparation of rare-earth luminescent nanomaterials without increasing reaction complexity, offering advantages such as high yield, controllable product morphology and size, low energy consumption, and good reproducibility. Through parameter control, the preparation of rare-earth luminescent nanomaterials with various sizes and morphologies can be achieved.

Description

Technical Field

[0001] This invention belongs to the field of rare earth nanoluminescent material preparation technology, specifically relating to a large-scale synthesis equipment and preparation method for rare earth nanoluminescent materials. Background Technology

[0002] Rare-earth ion upconversion luminescence possesses characteristics such as large anti-Stokes shift, wide spectral distribution, narrow peak width, long luminescence lifetime, and no fluorescence bleaching, making rare-earth upconversion luminescent materials promising for broad applications and significant practical value in fields such as bioimaging, photodynamic therapy, information storage, fluorescence detection, infrared detection, and optical encryption. However, their practical application and industrialization heavily rely on the stable, reproducible, and large-scale preparation capabilities of high-quality rare-earth nanoluminescent materials. The level of large-scale preparation directly affects the consistency of material properties, device reliability, and the scalability of application scenarios, making it a key link in achieving deviceization and supply chain integration.

[0003] Currently, commonly used laboratory synthesis methods include thermal decomposition, high-temperature coprecipitation, and hydrothermal / solvothermal methods. While these methods can effectively control the particle size, morphology, phase composition, and doping ratio of rare-earth luminescent nanomaterials on a milligram to hundred-milligram scale, they generally suffer from problems such as uneven heat and mass transfer, difficulty in precisely controlling reaction conditions, difficulty in maintaining pure phase, widening of particle size distribution, and significant batch-to-batch fluctuations in luminescence performance when scaled up to gram-level or higher production. Furthermore, these methods typically rely on high-temperature conditions, toxic or volatile precursors, strictly inert atmospheres or vacuum environments, and expensive surfactants, placing high demands on equipment and safety, and creating significant environmental and cost pressures, severely restricting their industrial application.

[0004] Therefore, there is an urgent need for a large-scale synthesis equipment and preparation method that is suitable for mass production, has mild process conditions, good repeatability, and can stably obtain high-quality rare earth nanoluminescent materials. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention provides a large-scale synthesis apparatus and preparation method for rare-earth luminescent nanomaterials. The large-scale synthesis apparatus for rare-earth luminescent nanomaterials integrates multiple parallel reaction units with centralized heating and stirring. By constructing multiple parallel and equivalent small reaction units within the same main reactor and utilizing a unified thermal field and synchronous stirring mechanism, multiple liquid-phase reaction systems simultaneously complete nucleation, growth, and phase transformation processes under highly consistent reaction kinetics conditions. This achieves stable large-scale preparation of rare-earth luminescent nanomaterials without increasing reaction complexity.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] This invention provides a large-scale synthesis apparatus for rare earth nano-luminescent materials, comprising a main reactor, a stirring device, a reaction device, support legs, a feeding system, and a control system; the reaction device is located inside the main reactor; the support legs are used to support and fix the main reactor;

[0008] The stirring device includes a motor, a reducer, a main stirring shaft, a gearbox, several sub-stirring shafts, several stirring paddles, and a first support; the motor, reducer, main stirring shaft, gearbox, sub-stirring shafts, and stirring paddles are connected in sequence; the first support is used to fix the gearbox inside the main reaction vessel;

[0009] The reaction apparatus includes several small reactors, a heating device, a rotating disk, a rotating device, and a second support; the second support is used to fix the rotating device inside the main reaction vessel; the rotating disk is mounted on the rotating device and can rotate; the heating device is used to heat the small reactors; the several small reactors are distributed circumferentially on the rotating disk along the main stirring shaft;

[0010] The stirring paddle is located inside the small reactor;

[0011] The feeding system is used to feed materials into a small reactor;

[0012] The control system is used to control the stirring device, the reaction device, and the feeding system.

[0013] Preferably, the main reactor includes a cylinder, a lid, a gasket, a flange, a nut, and a screw; the gasket, flange, nut, and screw are used to fix and seal the cylinder and lid.

[0014] More preferably, the bottom of the cylinder is provided with a first drain pipe and a first valve for draining the reaction liquid after the reaction.

[0015] More preferably, the vessel lid is provided with a first feeding hole, an inert gas hole, a vacuum hole, a vacuum gauge, a pressure gauge, and a second feeding hole.

[0016] More preferably, the first feeding port is equipped with a valve, the inert gas port is equipped with a valve, the vacuum port is equipped with a valve, and the second feeding port is equipped with a valve.

[0017] More preferably, the feeding system includes a first feeding pipe and a second feeding pipe, the first feeding pipe being connected to a first feeding hole and the second feeding pipe being connected to a second feeding hole.

[0018] Preferably, the gearbox is a single-drive multi-synchronous transmission gearbox.

[0019] Preferably, the number of the sub-stirring shafts, the number of stirring paddles, and the number of small reactors are the same.

[0020] Preferably, the rotating device can drive a rotating disk to rotate around the main stirring shaft.

[0021] Preferably, the small reactor is provided with a second drain pipe and a second valve at the bottom; used to collect the reaction liquid after the reaction to the bottom of the cylinder.

[0022] Preferably, the heating device is arranged around the outside of the small reactor for uniform heating.

[0023] Preferably, the heating device is an electric heating device.

[0024] This invention provides a method for the large-scale preparation of rare-earth luminescent nanomaterials, using the aforementioned large-scale synthesis equipment, and comprising the following steps:

[0025] (1) Rare earth acetate precursor and sodium hydrofluoride are added to a small reactor through a feeding system. After repeated vacuuming and filling with inert gas to remove air, the heating and stirring devices are controlled by a control system to react and obtain a rare earth nanoluminescent material solution.

[0026] (2) Add ethanol to the obtained rare earth nanoluminescent material solution, then centrifuge, dry and ball mill to obtain rare earth nanoluminescent material.

[0027] Preferably, the rare earth acetate precursor comprises yttrium acetate, ytterbium acetate, erbium acetate, oleic acid, and 1-octadecene, wherein the molar ratio of yttrium acetate, ytterbium acetate, and erbium acetate is (78-82):(16-20):2, the volume ratio of oleic acid to 1-octadecene is 14:(7-16), and the ratio of the total molar amount of yttrium acetate, ytterbium acetate, and erbium acetate to the total volume of oleic acid and 1-octadecene is 1 mmol:(2-4) mL.

[0028] More preferably, the rare earth acetate precursor comprises yttrium acetate, ytterbium acetate, erbium acetate, oleic acid, and 1-octadecene, wherein the molar ratio of yttrium acetate, ytterbium acetate, and erbium acetate is 80:18:2, the volume ratio of oleic acid to 1-octadecene is 2:1 or 7:8, and the ratio of the total molar amount of yttrium acetate, ytterbium acetate, and erbium acetate to the total volume of oleic acid and 1-octadecene is 1 mmol:3 mL.

[0029] Preferably, the molar ratio of sodium hydrofluoride to the total molar ratio of yttrium acetate, ytterbium acetate and erbium acetate is (2-3):1.

[0030] More preferably, the molar ratio of sodium hydrofluoric acid to the total molar ratio of yttrium acetate, ytterbium acetate and erbium acetate is 2:1.

[0031] Preferably, the temperature program for the reaction is as follows: heating to 240-260 ℃ at a heating rate of 5-10 ℃ / min, then holding at that temperature for 30-60 min, and after holding at that temperature, heating to 300-320 ℃ at a heating rate of 2-5 ℃ / min, then holding at that temperature for 30-60 min.

[0032] More preferably, the temperature program of the reaction is as follows: heating to 250 °C at a heating rate of 7.5 °C / min, holding at that temperature for 40 min, and after holding at that temperature, heating to 310 °C at a heating rate of 2 °C / min, and then holding at that temperature for 50 min; or heating to 250 °C at a heating rate of 7.5 °C / min, holding at that temperature for 30 min, and after holding at that temperature, heating to 310 °C at a heating rate of 2 °C / min, and then holding at that temperature for 30 min.

[0033] Preferably, the stirring rate of the reaction is 200-500 r / min.

[0034] Preferably, the volume ratio of the rare earth nanoluminescent material solution to ethanol is 1:(1-3).

[0035] This invention enables the reproducible control of the particle size, morphology, and luminescence properties of rare-earth nanoluminescent materials by adjusting the precursor composition ratio, heating rate, and holding time.

[0036] The beneficial effects of this invention are:

[0037] This invention achieves synchronous transmission between the main stirring shaft and the secondary stirring shafts via a gearbox, and controls the temperature, stirring speed, and reaction time in a unified manner. Each small reactor reacts in parallel, enabling the large-scale preparation of rare earth nano-luminescent materials. It effectively solves the problems of uneven heat and mass transfer and poor batch consistency in traditional methods. It has the advantages of high yield, controllable product morphology and size, low energy consumption, and good repeatability, and is suitable for the industrial production of high-quality rare earth upconversion nanomaterials.

[0038] This invention enables the preparation of rare earth nanoluminescent materials of various sizes and morphologies through parameter control. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of the equipment for the large-scale synthesis of rare earth nanoluminescent materials of the present invention;

[0040] Figure 2 This is a schematic diagram of the structure of the equipment for the large-scale synthesis of rare earth nanoluminescent materials of the present invention;

[0041] Figure 3 This is a schematic diagram showing the arrangement of multiple small reactors;

[0042] Figure 4 A flowchart of a method for large-scale preparation of rare-earth luminescent nanomaterials;

[0043] Figure 5 TEM, XRD, and emission spectra of the rare-earth-doped nanoluminescent material prepared in Example 2 under 980 nm laser excitation;

[0044] Figure 6 TEM, XRD, and emission spectra of the rare-earth-doped nanoluminescent material prepared in Example 3 under 980 nm laser excitation;

[0045] Figure 7 The images show the TEM, XRD, and emission spectra of the rare-earth-doped luminescent nanomaterials prepared in Example 4 under 980 nm laser excitation.

[0046] Among them, 1. main reactor, 2. stirring device, 3. reaction device, 4. support leg, 5. feeding system, 6. control system;

[0047] 11. Shell body; 12. Lid; 13. Gasket; 14. Flange; 15. Nut; 16. Screw.

[0048] 111. First drain pipe; 112. First valve;

[0049] 121. First feed port; 122. Inert gas port; 123. Vacuum port; 124. Vacuum gauge; 125. Pressure gauge; 126. Second feed port;

[0050] 21. Motor; 22. Reducer; 23. Main stirring shaft; 24. Gearbox; 25. Sub-stirring shaft; 26. Stirring paddle; 27. First support.

[0051] 31. Small reactor; 32. Second drain pipe; 33. Second valve; 34. Heating device; 35. Rotating disk; 36. Rotating device; 37. Second support.

[0052] 51. First feeding pipe; 52. Second feeding pipe. Detailed Implementation

[0053] The present invention will be further described below with reference to embodiments.

[0054] The following will clearly and completely describe the concept, specific solutions, and technical effects of the present invention with reference to embodiments, so as to fully understand the purpose, features, and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. The various technical features in the present invention can be combined interactively without contradicting each other.

[0055] Example 1

[0056] This invention provides a large-scale synthesis apparatus for rare-earth nanoluminescent materials, referenced in [reference]. Figures 1-3 It includes a main reactor 1, a stirring device 2, a reaction device 3, support legs 4, a feeding system 5, and a control system 6;

[0057] The main reactor 1 is fixed to the ground by support legs 4;

[0058] The main reactor 1 includes a cylinder 11, a lid 12, a gasket 13, a flange 14, a nut 15, and a screw 16; the cylinder 11 is connected to the lid 12 through the gasket 13, flange 14, nut 15, and screw 16 (sealing structure) to form a closed chamber to ensure the sealing of the reaction process; the lid is located on the top of the main reactor.

[0059] The bottom of the cylinder 11 is provided with a first drain pipe 111 and a first valve 112 for discharging the reaction liquid after the reaction.

[0060] The vessel lid 12 is provided with a first feeding port 121, an inert gas port 122, a vacuum port 123, a vacuum gauge 124, a pressure gauge 125, and a second feeding port 126. The first feeding port 121 is used to inject the precursor solution and is equipped with a valve; the inert gas port 122 is used to inject inert gas and is equipped with a valve; the vacuum port 123 is used to evacuate and is equipped with a valve; the vacuum gauge 124 and the pressure gauge 125 are used to measure and monitor the vacuum degree and pressure; and the second feeding port 126 is used to inject sodium hydrofluoric acid and is equipped with a valve.

[0061] The stirring device 2 includes a motor 21, a reducer 22, a main stirring shaft 23, a gearbox 24, several sub-stirring shafts 25, several stirring paddles 26, and a first support 27. The motor, reducer, and main stirring shaft are connected in sequence. The main stirring shaft drives the sub-stirring shafts through the gearbox. The gearbox is fixed to the cylinder through the first support. Each sub-stirring shaft is equipped with a stirring paddle at its end. The number of sub-stirring shafts corresponds to the number of small reactors. The stirring paddles are located inside the small reactors. The main stirring shaft is located at the center of the main reactor. The upper end of the main stirring shaft passes through the reactor cover and is connected to the driving device. The main stirring shaft is synchronously linked with multiple sub-stirring shafts through the gearbox, so that when the main stirring shaft rotates, each sub-stirring shaft rotates synchronously. The reaction system in each small reactor reacts in parallel under the same stirring conditions. The shear rate of the reaction system in each small reactor remains consistent, thereby ensuring the synchronicity of the nucleation and growth processes.

[0062] The gearbox 24 has the capability of "one-drive-multiple" synchronous transmission; an example is one-drive-eight.

[0063] The reaction device 3 is located inside the main reaction vessel 1;

[0064] The reaction apparatus 3 includes several small reactors 31 (e.g., eight). Figure 3 The reactor has dimensions of Ø120mm×H200mm; the number and size of the small reactors can be flexibly set according to the actual reaction scale and output, and the number of synchronous drives of the gearbox can be adjusted accordingly. It also includes a heating device 34, a rotating disk 35, a rotating device 36, and a second support 37. The second support is fixed to the cylinder, the rotating device is located at the center of the second support, and the rotating disk is located on the rotating device. Several small reactors are evenly installed on the rotating disk, and the small reactors are evenly distributed around the main stirring shaft, preferably in a ring arrangement. Each small reactor has a sub-stirring shaft above it, and a stirring paddle is installed at the lower end of the sub-stirring shaft. The stirring paddle can be driven by a motor. A heating device is arranged around the outer wall of the small reactor. The heating device is an electric heating device, used to provide a stable and uniform reaction temperature for the reaction system. The heating device is electrically connected to the control system, which precisely controls the reaction temperature. The heating device forms a uniform temperature field, and the reaction temperature difference between the small reactors is controlled within ±2℃.

[0065] The rotating device 36 can drive the rotating disk 35 to rotate around the main stirring shaft 23.

[0066] The small reactor 31 is equipped with a second drain pipe 32 and a second valve 33 at the bottom; used to collect the reaction liquid after the reaction to the bottom of the cylinder 11.

[0067] The feeding system 5 includes a first feeding pipe 51 and a second feeding pipe 52. The first feeding pipe 51 is connected to the first feeding hole 121 and feeds each small reactor 31 by rotating the rotating disk 35. The second feeding pipe 52 is connected to the second feeding hole 126 and feeds each small reactor 31 by rotating the rotating disk 35.

[0068] The control system 6 is used to control valves, stirring devices, heating devices, rotating devices, etc.; it can uniformly control the heating temperature, heating rate and heating time of the heating device, control the stirring speed of the stirring device, control the opening and closing of the valves, and control the rotation and rotation angle of the rotating device.

[0069] The operation mode of the large-scale synthesis equipment for the rare-earth nanoluminescent materials of the present invention is as follows:

[0070] After the device is assembled, the first feeding port 121 is connected to the precursor preparation tank, the inert gas port 122 is connected to the inert gas cylinder, the vacuum port 123 is connected to the vacuum pump, the second feeding port 126 is connected to the sodium hydrofluoride addition pump, and the first drain pipe 111 is connected to the storage tank, centrifuge, oven and ball mill in sequence.

[0071] The materials are added to the precursor preparation tank to prepare the precursor solution. The precursor solution and sodium hydrofluoric acid are injected into the small reactor 31 through the feeding system. The main reactor 1 is made into an inert gas atmosphere by evacuation-filling-evacuation-filling. The stirring device 2 and the heating device 34 are started by the control system. The reaction is carried out under stirring and heating conditions. After the reaction, the reaction liquid is collected to the bottom of the cylinder 11 through the second drain pipe 32, and then collected to the storage tank through the first drain pipe 111. The reaction liquid is then centrifuged, dried and ball-milled in sequence to obtain rare earth nanoluminescent materials.

[0072] The large-scale synthesis equipment of this invention enables the liquid-phase reaction system in multiple small reactors to maintain a high degree of consistency in heat transfer conditions, stirring and shear conditions, and reaction time scale, thereby achieving the synchronous occurrence of reaction nucleation, growth, and crystal phase transformation processes.

[0073] Accordingly, this invention also provides a method for the large-scale preparation of rare-earth luminescent nanomaterials, using the aforementioned large-scale synthesis equipment, with reference to... Figure 4 This includes the following steps:

[0074] (1) Rare earth acetate precursor and sodium hydrofluoride are added to a small reactor through a feeding system at a certain stoichiometric ratio. The solution in each small reactor does not exceed 2 / 3 of its volume. After the chamber is sealed, the air is removed by repeated vacuuming and inert gas filling process (repeated twice, with vacuuming time of 5-10 min and filling time of 1-3 min). The heating time, heating temperature, heating rate and stirring speed are controlled by the control system. The temperature is raised to 250 ℃ at a heating rate of 5-10 ℃ / min, and then held for 30-60 min. After the holding time is completed, the temperature is raised to 310 ℃ at a heating rate of 2-5 ℃ / min, and then held for 30-60 min. The gas pressure in the main reactor is monitored by a barometer during the reaction.

[0075] (2) During the heating process, sodium hydrofluoride decomposes into active sodium fluoride and hydrogen fluoride in the rare earth acetate precursor solution, and nucleates with rare earth ions at the solid-liquid interface. Subsequently, growth and phase transformation occur to form rare earth doped nanoluminescent materials with uniform size. All processes are completed in a small reactor.

[0076] (3) After the heat preservation is completed, stop heating, cool to room temperature, and collect the rare earth-doped nanoluminescent material solution in the vertical storage tank;

[0077] (4) Add a certain amount of ethanol to the obtained rare earth-doped nanoluminescent material solution, and then perform centrifugation, drying, ball milling and other processes to obtain the final product.

[0078] Example 2

[0079] The NaYF4:Yb,Er luminescent nanomaterials were prepared using the large-scale synthesis equipment and preparation method of the rare earth nanoluminescent materials described in Example 1 of this invention, specifically including the following steps:

[0080] 2000 mmol of a mixed precursor containing yttrium acetate, ytterbium acetate, erbium acetate, oleic acid, and 1-octadecene was added to eight small reactors via a feeding system. The molar ratio of yttrium acetate, ytterbium acetate, and erbium acetate was 80:18:2. Oleic acid was added in 4000 mL portions, and 1-octadecene in 2000 mL portions, totaling 6000 mL. 750 mL of rare earth precursor solution was added to each small reactor. Subsequently, 500 mmol of sodium hydrofluoric acid powder was added to each small reactor, totaling 4000 mmol. After the chambers were sealed, the main reactor was subjected to a vacuum pump and parallel inert gas (argon) cylinders for evacuation-purging-evacuation-purging cycles, with evacuation time of 8 min and purging time of 2 min. The heating time, heating temperature, heating rate, and stirring speed were then controlled using a control system. Maintaining a stirring rate of 330 r / min, the temperature was increased to 250 ℃ at a heating rate of 7.5 ℃ / min, and then held for 40 min. After the holding period, the temperature was increased to 310 ℃ at a heating rate of 2 ℃ / min, and then held for 50 min. After the holding period, heating was stopped, and the mixture was cooled to room temperature. After the stirring was stopped, the solution containing rare earth-doped nanoluminescent materials was collected into a vertical storage tank through the valves of the small reactor and the cylinder. Finally, a large amount of rare earth-doped nanoluminescent material powder was obtained through ethanol precipitation (reaction solution to ethanol volume ratio of 1:1), centrifugation, drying, and ball milling.

[0081] The TEM, XRD, and emission spectra of the NaYF4:Yb,Er nanoluminescent material prepared in this embodiment under 980 nm laser excitation are shown below. Figure 5 .

[0082] Example 3

[0083] NaYF4:Yb,Er luminescent nanomaterials were prepared using the large-scale synthesis equipment and preparation method of rare earth nanoluminescent materials in Example 1 of this invention. The size, morphology, and luminescent properties differed from those in Example 2. Specifically, the preparation included the following steps:

[0084] 2000 mmol of a mixed precursor containing yttrium acetate, ytterbium acetate, erbium acetate, oleic acid, and 1-octadecene was added to eight small reactors via a feeding system. The molar ratio of yttrium acetate, ytterbium acetate, and erbium acetate was 80:18:2. Oleic acid was added in 2800 mL, and 1-octadecene in 3200 mL, totaling 6000 mL. 750 mL of rare earth precursor solution was added to each small reactor. Subsequently, 500 mmol of sodium hydrofluoric acid powder was added to each small reactor, totaling 4000 mmol. After the chambers were sealed, the main reactor was evacuated and purged using a vacuum pump and a parallel inert gas (argon) cylinder. The evacuation time was 8 min, and the purging time was 2 min. The heating time, heating temperature, heating rate, and stirring speed were then controlled using a control system. Maintaining a stirring rate of 330 r / min, the temperature was increased to 250 ℃ at a heating rate of 7.5 ℃ / min, and then held for 40 min. After the holding period, the temperature was increased to 310 ℃ at a heating rate of 2 ℃ / min, and then held for 50 min. After the holding period, heating was stopped, and the mixture was cooled to room temperature. After the stirring was stopped, the solution containing rare earth-doped nanoluminescent materials was collected into a vertical storage tank through the valves of the small reactor and the cylinder. Finally, a large amount of rare earth-doped nanoluminescent material powder was obtained through ethanol precipitation (reaction solution to ethanol volume ratio of 1:1), centrifugation, drying, and ball milling.

[0085] The TEM, XRD, and emission spectra of the NaYF4:Yb,Er nanoluminescent material prepared in this embodiment under 980 nm laser excitation are shown below. Figure 6 .

[0086] Example 4

[0087] NaYF4:Yb,Er luminescent nanomaterials were prepared using the large-scale synthesis equipment and preparation method of rare earth nanoluminescent materials in Example 1 of this invention. The size, morphology, and luminescent properties differed from those in Example 2. Specifically, the preparation included the following steps:

[0088] 2000 mmol of a mixed precursor containing yttrium acetate, ytterbium acetate, erbium acetate, oleic acid, and 1-octadecene was added to eight small reactors via a feeding system. The molar ratio of yttrium acetate, ytterbium acetate, and erbium acetate was 80:18:2. Oleic acid was added in 4000 mL portions, and 1-octadecene in 2000 mL portions, totaling 6000 mL. 750 mL of rare earth precursor solution was added to each small reactor. Subsequently, 500 mmol of sodium hydrofluoric acid powder was added to each small reactor, totaling 4000 mmol. After the chambers were sealed, the main reactor was subjected to a vacuum pump and parallel inert gas (argon) cylinders for evacuation-purging-evacuation-purging cycles, with evacuation time of 8 min and purging time of 2 min. The heating time, heating temperature, heating rate, and stirring speed were then controlled using a control system. Maintaining a stirring rate of 330 r / min, the temperature was increased to 250 ℃ at a heating rate of 7.5 ℃ / min, and then held for 30 min. After the holding period, the temperature was increased to 310 ℃ at a heating rate of 2 ℃ / min, and then held for 30 min. After the holding period, heating was stopped, and the mixture was cooled to room temperature. After the stirring was stopped, the solution containing rare earth-doped nanoluminescent materials was collected into a vertical storage tank through the valves of the small reactor and the cylinder. Finally, a large amount of rare earth-doped nanoluminescent material powder was obtained through ethanol precipitation (reaction solution to ethanol volume ratio of 1:1), centrifugation, drying, and ball milling.

[0089] The TEM, XRD, and emission spectra of the NaYF4:Yb,Er nanoluminescent material prepared in this embodiment under 980 nm laser excitation are shown below. Figure 7 .

[0090] from Figure 5-7 It can be seen that the NaYF4:Yb,Er nanoluminescent materials prepared by different process parameters in Examples 2-4 have different sizes, morphologies and luminescence properties, and have high yield and good uniformity; the particle size of Examples 2-4 decreases in turn, and the luminescence intensity decreases in turn.

[0091] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present invention.

Claims

1. A large-scale synthesis device for rare-earth nanoluminescent materials, characterized in that, It includes a main reactor (1), a stirring device (2), a reaction device (3), a support leg (4), a feeding system (5), and a control system (6); the reaction device (3) is located inside the main reactor (1); the support leg (4) is used to support and fix the main reactor (1); The stirring device (2) includes a motor (21), a reducer (22), a main stirring shaft (23), a gearbox (24), several sub-stirring shafts (25), several stirring paddles (26), and a first support (27); the motor (21), reducer (22), main stirring shaft (23), gearbox (24), sub-stirring shafts (25), and stirring paddles (26) are connected in sequence; the first support (27) is used to fix the gearbox (24) inside the main reactor (1); The reaction apparatus (3) includes several small reactors (31), a heating device (34), a rotating disk (35), a rotating device (36), and a second support (37); the second support (37) is used to fix the rotating device (36) inside the main reaction vessel (1); the rotating disk (35) is mounted on the rotating device (36) and can rotate; the heating device (34) is used to heat the small reactors (31); the several small reactors (31) are distributed circumferentially on the rotating disk (35) along the main stirring shaft (23); The stirring paddle (26) is located inside the small reactor (31); The feeding system (5) is used to feed the small reactor (31); The control system (6) is used to control the stirring device (2), the reaction device (3) and the feeding system (5).

2. The equipment for large-scale synthesis of rare earth nanoluminescent materials according to claim 1, characterized in that, The main reactor (1) includes a cylinder (11), a lid (12), a gasket (13), a flange (14), a nut (15), and a screw (16).

3. The equipment for large-scale synthesis of rare earth nanoluminescent materials according to claim 2, characterized in that, The bottom of the cylinder (11) is provided with a first drain pipe (111) and a first valve (112). The vessel lid (12) is provided with a first feeding hole (121), an inert gas hole (122), a vacuum hole (123), a vacuum gauge (124), a pressure gauge (125), and a second feeding hole (126).

4. The equipment for large-scale synthesis of rare-earth nanoluminescent materials according to claim 3, characterized in that, The first feeding port (121) is equipped with a valve, the inert gas port (122) is equipped with a valve, the vacuum port (123) is equipped with a valve, and the second feeding port (126) is equipped with a valve.

5. The equipment for large-scale synthesis of rare earth nanoluminescent materials according to claim 3, characterized in that, The feeding system (5) includes a first feeding pipe (51) and a second feeding pipe (52). The first feeding pipe (51) is connected to the first feeding hole (121), and the second feeding pipe (52) is connected to the second feeding hole (126).

6. The equipment for large-scale synthesis of rare earth nanoluminescent materials according to claim 1, characterized in that, The gearbox (24) is a single-drive multi-synchronous transmission gearbox; The number of the sub-stirring shafts (25), the number of stirring paddles (26), and the number of small reactors (31) are the same; The rotating device (36) can drive the rotating disk (35) to rotate around the main stirring shaft (23).

7. The equipment for large-scale synthesis of rare-earth nanoluminescent materials according to claim 1, characterized in that, The small reactor (31) is equipped with a second drain pipe (32) and a second valve (33) at the bottom; The heating device (34) is arranged around the outside of the small reactor (31); The heating device (34) is an electric heating device.

8. A method for large-scale preparation of rare-earth nanoluminescent materials, characterized in that, The rare earth nanoluminescent materials are prepared using the large-scale synthesis equipment described in any one of claims 1-7, and include the following steps: (1) Rare earth acetate precursor and sodium hydrofluoride are added to a small reactor through a feeding system (5). After repeated vacuuming and filling with inert gas to remove air, the heating device (34) and stirring device (2) are controlled by a control system (6) to react and obtain a rare earth nanoluminescent material solution. (2) Add ethanol to the obtained rare earth nanoluminescent material solution, then centrifuge, dry and ball mill to obtain rare earth nanoluminescent material.

9. The method for preparing rare-earth nanoluminescent materials according to claim 8, characterized in that, The rare earth acetate precursor comprises yttrium acetate, ytterbium acetate, erbium acetate, oleic acid, and 1-octadecene, wherein the molar ratio of yttrium acetate, ytterbium acetate, and erbium acetate is (78-82):(16-20):2, the volume ratio of oleic acid to 1-octadecene is 14:(7-16), and the ratio of the total molar amount of yttrium acetate, ytterbium acetate, and erbium acetate to the total volume of oleic acid and 1-octadecene is 1 mmol:(2-4) mL. The molar ratio of sodium hydrofluoric acid to the total molar ratio of yttrium acetate, ytterbium acetate, and erbium acetate is (2-3):

1.

10. The method for preparing rare-earth nanoluminescent materials according to claim 8, characterized in that, The temperature program for the reaction is as follows: heat to 240-260 ℃ at a heating rate of 5-10 ℃ / min, then hold at that temperature for 30-60 min, and after holding at that temperature, heat to 300-320 ℃ at a heating rate of 2-5 ℃ / min, then hold at that temperature for 30-60 min. The stirring rate of the reaction is 200-500 r / min; The volume ratio of the rare earth nanoluminescent material solution to ethanol is 1:(1-3).

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