A nano fluorescent ceramic and its preparation method and application

Abstract

The present invention provides a nano fluorescent ceramic and its preparation method and application. The molecular formula of the nano fluorescent ceramic is A 3‑x B5O 12 :xCe, wherein the A element includes at least one of Y, Lu, Gd, and Tb elements, and the B element includes at least one of Al, Mg, and Si elements, wherein the Lu content in the A element is greater than 50%, the Al content in the B element is greater than 50%, and the Ce element replaces part of the A element and occupies its lattice site as a luminescent center, wherein 0

Description

Technical Field

[0001] The present invention relates to the technical field of fluorescent materials and laser lighting, and in particular to a nano fluorescent ceramic and a preparation method and application thereof. Background Art

[0002] Compared with LED light sources, lasers have advantages such as good directionality, high beam quality, high electro-optical conversion efficiency, long life, small size, and compact structure. They can be used in many fields such as security, ocean, and transportation. Among all-inorganic fluorescent conversion materials such as fluorescent single crystals, fluorescent glass, and fluorescent ceramics, fluorescent ceramics have the advantages of high reliability, good physical and chemical stability, and high thermal conductivity. They are an efficient and stable fluorescent conversion material and a key material in high-power and high-brightness laser lighting applications. The schematic diagram of nano or micro fluorescent ceramics enhancing light scattering is shown in the figure below. Figure 2 shown.

[0003] In laser lighting, luminous efficiency is a key performance indicator for fluorescent ceramics. Luminous efficiency refers to the ratio of the luminous flux emitted by a light source to its input power. Higher luminous efficiency indicates a greater ability of the lighting device to convert electrical energy into light. Laser lighting utilizes a single-wavelength, small-spot laser beam as excitation light. This results in a small excitation area for the fluorescent ceramic, limiting the light extraction efficiency and excitation light utilization rate at the luminescent center.

[0004] Patents CN112441817A and CN109467453A improve the luminous efficiency of micron-sized fluorescent ceramics by introducing pores within the micron-sized ceramics to enhance the scattering and absorption of incident laser light. However, the introduction of pores often reduces the thermal conductivity of the fluorescent ceramics, preventing rapid heat conduction and causing accumulation, resulting in thermal quenching. Introducing a second phase into fluorescent ceramics can also enhance the scattering of incident laser light. Patents CN112110729A and CN109678475A produce micron-sized fluorescent ceramics with high thermal conductivity by introducing an Al2O3 second phase. However, their light scattering, absorption, and scattering properties are limited, resulting in luminous efficiencies of only 113 lumens per watt and 98 lumens per watt, respectively.

[0005] In summary, compared to LED light sources, lasers have a smaller spot area, and micron-sized grains scatter less laser light, resulting in lower luminous efficiency in micron-sized fluorescent ceramics for laser illumination. Introducing pores and a second phase to enhance the scattering and absorption of incident laser light can effectively improve the luminous efficiency of micron-sized fluorescent ceramics, but this can lead to inverse developments in luminous efficiency and thermal conductivity. Nanosized grains, on the other hand, effectively enhance the scattering of incident laser light while maintaining high thermal conductivity, making them a preferred approach for enhancing the luminous efficiency of fluorescent ceramics. Summary of the Invention

[0006] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art and to provide a nano fluorescent ceramic and a preparation method and application thereof.

[0007] In order to achieve the above-mentioned purpose, the present invention provides a nano fluorescent ceramic in the first aspect, wherein the molecular formula of the nano fluorescent ceramic is A 3-x B5O 12 :xCe, wherein the A element includes at least one of Y, Lu, Gd, and Tb, and the B element includes at least one of Al, Mg, and Si; wherein, when the A element includes Lu and other elements, the Lu content is greater than 50%; when the B element includes Al and other elements, the Al content is greater than 50%; the Ce element replaces part of the A element and occupies its lattice site as a luminescent center, wherein, 0 <x≤0.015。

[0008] In one embodiment, the crystal structure of the crystalline phase of the nano fluorescent ceramic is the same as that of yttrium aluminum garnet, and the crystal particle size ranges from 80 to 1000 nanometers.

[0009] In one embodiment, the density of the nano fluorescent ceramic is not less than 95%.

[0010] In one embodiment, the nano fluorescent ceramic can emit broadband fluorescence with a peak wavelength in the range of 500 to 600 nanometers under the excitation of a blue light source, and the quantum efficiency is not less than 50%.

[0011] In a second aspect, the present invention provides a method for preparing a nano fluorescent ceramic, comprising:

[0012] Preparation of nanoscale raw materials;

[0013] Nano-fluorescent ceramics are obtained by sintering nano-scale raw materials using an ultra-fast sintering process.

[0014] In one embodiment, a method for preparing a nanoscale raw material includes:

[0015] Preparation of nanopowder of element A oxide: dissolving micron powder of element A oxide in excess nitric acid, placing in a reactor and reacting in an oven for 24 hours to obtain a reaction solution, removing the solution, adding an appropriate amount of supersaturated ammonium bicarbonate solution, stirring until the reaction is complete, neutralizing the solution with the remaining nitric acid, and reacting with the reaction solution to precipitate, centrifuging 3-5 times with deionized water or ethanol, drying in an oven, removing the solution, grinding it, transferring it to a muffle furnace, and calcining it at 900 degrees Celsius for 2 hours to obtain nanopowder of element A oxide; the particle size of the nanopowder of element A oxide is within 100 nanometers;

[0016] Nanopowders of element A oxide, nanopowders of element B oxide, and CeO2 are weighed in stoichiometric ratios, and 0.1% of a dispersant and 0.5% of a sintering aid are added to the raw materials to obtain a nano raw material mixture:

[0017] The nano-raw material mixture is ball-milled for 20 to 40 hours to be fully mixed, taken out, dried, ground and sieved to obtain the nano-scale raw material.

[0018] In one embodiment, an ultra-fast sintering process is used to sinter nanoscale raw materials to produce nano fluorescent ceramics, including:

[0019] The nanoscale raw materials are dry pressed to obtain a green body at a pressure of 20 to 60 kilonewtons;

[0020] The green body is placed in a muffle furnace for debinding, then subjected to cold isostatic pressing at 250 MPa, and finally placed in a pulsed Joule heat rapid sintering device. Nano-fluorescent ceramics are obtained by in-situ reaction sintering within 20 seconds at a sintering temperature of 1500-2000 degrees Celsius.

[0021] In one embodiment, the sintering process uses a heating and cooling rate of about 100,000 degrees Celsius per second.

[0022] In a third aspect, the present invention provides an application of nano fluorescent ceramics in the field of laser lighting.

[0023] The advantages and beneficial effects of the present invention over the prior art are:

[0024] (1) By regulating the sintering temperature and time, the present invention can produce nano-fluorescent ceramics with a particle size of 80 to 1000 nanometers. The nano-sized grains can effectively enhance the scattering of incident laser light, thereby improving the luminous efficiency. By optimizing the preparation process and sintering conditions, nano-fluorescent ceramics with a particle size range of 80 to 1000 nanometers can be obtained, with an internal quantum efficiency of up to 90% and a luminous efficiency of up to 248 lumens per watt. By regulating the composition, nano-fluorescent ceramics of different colors can be obtained. They can be effectively excited by blue laser light and emit broadband fluorescence with a peak wavelength of 500 to 600 nanometers.

[0025] (2) The ultra-fast preparation method for nano-luminescent ceramics provided by the present invention utilizes nanoscale raw materials and an ultra-rapid thermal shock strategy to achieve in-situ reaction sintering of the nano-luminescent ceramics. This method simplifies the preparation process and achieves rapid sintering. Furthermore, it achieves high doping of luminescent centers while maintaining constant quantum efficiency, thereby increasing the light saturation threshold of the fluorescent ceramics.

[0026] (3) The nano-fluorescent ceramics of the present invention have many advantages, including small particle size, high efficiency, good luminous efficacy, high light intensity, adjustable color, and long life. Furthermore, the prepared nano-fluorescent ceramics have high thermal conductivity and can be effectively excited by blue lasers. The nano-sized grains can enhance the scattering of incident laser light, improve the light conversion efficiency of blue lasers, and obtain a high-brightness lighting source. It is expected that the nano-fluorescent ceramics of the present invention and the preparation method will be widely used and developed in the field of laser lighting. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a process flow chart of the present invention;

[0028] Figure 2 Schematic diagram of enhanced light scattering of nano-fluorescent ceramics;

[0029] Figure 3 The morphology of the nano-Lu2O3 powder prepared by the coprecipitation method in Example 1 is shown before and after treatment.

[0030] Figure 4 The nano-Lu3Al5O sintered at 1800 degrees Celsius for different times in Examples 2-6 12 : XRD pattern of Ce fluorescent ceramics;

[0031] Figure 5 The nano-Lu3Al5O sintered at 1800 degrees Celsius for different times in Examples 2-6 12 : Morphology of Ce fluorescent ceramics;

[0032] Figure 6 The nano-Lu3Al5O sintered at 1800 degrees Celsius for different times in Examples 2-6 12 :Grain growth curve of Ce fluorescent ceramics;

[0033] Figure 7 The nano-Lu3Al5O obtained in Example 1 at the extreme sintering times of 1800 degrees Celsius, 1900 degrees Celsius, and 2000 degrees Celsius 12 : Morphology of Ce fluorescent ceramics;

[0034] Figure 8 The nano-Lu3Al5O was obtained by sintering at 1800 degrees Celsius for 10 seconds in Example 7. 12 : Excitation spectrum of Ce fluorescent ceramics;

[0035] Figure 9 The nano-Lu3Al5O was obtained by sintering at 1800 degrees Celsius for 10 seconds in Example 7. 12 :Emission spectrum of Ce fluorescent ceramics;

[0036] Figure 10 XRD patterns of the nano-Lu3Al5O 12 :Ce fluorescent ceramics obtained in Example 8 and Example 9;

[0037] Figure 11 Morphology diagrams of the nano-Lu3Al5O 12 :Ce fluorescent ceramics obtained in Comparative Example 1. Detailed implementation manners

[0038] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and more understandable, the present invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0039] In the first aspect, the present invention provides a nano-fluorescent ceramic, and the molecular general formula of the nano-fluorescent ceramic is A 3- x B5O 12 :xCe, where the A element includes at least one of Y, Lu, Gd, and Tb elements, and the B element includes at least one of Al, Mg, and Si elements; wherein, when the A element contains Lu and other elements, the Lu content is greater than 50%; when the B element contains Al and other elements, the Al content is greater than 50%; the Ce element replaces part of the A element and occupies its lattice site as a luminescence center, where 0 < x ≤ 0.015. The set range of the luminescence center will not cause problems such as concentration quenching or transparency decrease.

[0040] Further, the crystal structure of the crystalline phase of the nano-fluorescent ceramic is the same as that of yttrium aluminum garnet, and the crystal particle size range is 80 to 1000 nanometers.

[0041] Further, the density of the nano-fluorescent ceramic is not less than 95%. The nanoparticles make the particles bind more tightly. A higher sintering temperature helps to increase the diffusion rate of ceramic particles and promote the binding between particles. The ultra-short sintering time reduces the grain growth and the formation of crystal defects during the sintering process, and finally a highly dense fluorescent ceramic is obtained.

[0042] Further, when excited by a blue light source (wavelength 440 - 470 nanometers), the nano-fluorescent ceramic can emit broadband fluorescence with a peak wavelength in the range of 500 - 600 nanometers, and the quantum efficiency is not less than 50%.

[0043] In the second aspect, the present invention provides a preparation method of a nano-fluorescent ceramic, and the technological process is as Figure 1As shown, nanoscale raw materials and an ultra-rapid thermal shock strategy are used to achieve in-situ reaction sintering of nano-luminescent ceramics. This method does not require post-processing processes such as secondary sintering and annealing. The sintering process used is to prepare nano-luminescent ceramics by in-situ reaction sintering within 20 seconds at a heating and cooling rate of about 100,000 degrees Celsius per second and a temperature of 1,500 to 2,000 degrees Celsius. The specific steps include:

[0044] Step S1, preparing nanoscale raw materials;

[0045] Step S2: using an ultra-fast sintering process to sinter the nanoscale raw materials to produce nano fluorescent ceramics.

[0046] Furthermore, the preparation method of the nanoscale raw material includes:

[0047] Preparation of nanopowder of element A oxide: dissolving micron powder of element A oxide in excess nitric acid, placing in a reactor and reacting in an oven for 24 hours to obtain a reaction solution, removing the solution, adding an appropriate amount of supersaturated ammonium bicarbonate solution, stirring until the reaction is complete, neutralizing the solution with the remaining nitric acid, and reacting with the reaction solution to precipitate, centrifuging 3-5 times with deionized water or ethanol, drying in an oven, removing the solution, grinding it, transferring it to a muffle furnace, and calcining it at 900 degrees Celsius for 2 hours to obtain nanopowder of element A oxide; the particle size of the nanopowder of element A oxide is within 100 nanometers;

[0048] Among them, the nanopowder of element A oxide (such as Lu2O3) is self-made, and the nanopowder of element B oxide (such as Al2O3) is commercially available raw materials;

[0049] Weighing nanopowders of element A oxide, element B oxide, and CeO2 in a stoichiometric ratio, and adding 0.1% of a dispersant and 0.5% of a sintering aid in a mass ratio to the raw materials to obtain a nano raw material mixture;

[0050] The dispersant and sintering aid added in the present invention are ammonium citrate and ethyl orthosilicate respectively, but are not limited to these two. Any dispersant and sintering aid that does not contain impurities and does not chemically react with the powder can be used, such as polyacrylic acid (PAA) as a dispersant and MgO as a sintering aid.

[0051] The nano-raw material mixture is ball-milled for 20 to 40 hours to be fully mixed, taken out, dried, ground and sieved to obtain a nano-scale raw material;

[0052] The preferred ball milling time is 28 hours, and the nano-scale raw material particle size after ball milling is the smallest. The drying temperature is 80 degrees Celsius and the drying time is 24 hours;

[0053] Furthermore, the nanoscale raw materials are sintered using an ultra-fast sintering process to produce nano fluorescent ceramics, including:

[0054] The nanoscale raw materials are dry-pressed to obtain a green body at a pressure of 20 to 60 kilonewtons, preferably 40 kilonewtons, so that the green body is relatively dense and will not be partially crushed or have internal defects due to excessive pressure;

[0055] The green body is placed in a muffle furnace for debinding, followed by a cold isostatic pressing process at 250 MPa to make the body more compact. Finally, it is placed in a pulsed Joule heat rapid sintering device and sintered in situ at a sintering temperature of 1500-2000 degrees Celsius within 20 seconds to obtain nano-luminescent ceramics. The optimal sintering temperature is 1800 degrees Celsius and the optimal sintering time is 10 seconds. When debinding in the muffle furnace, it can be treated at 800°C for 8 hours.

[0056] Furthermore, the heating and cooling rate of the sintering process is about 100,000 degrees Celsius per second.

[0057] In a third aspect, the present invention provides an application of nano fluorescent ceramics in the field of laser lighting.

[0058] When excited by blue laser (440-470 nanometers), the nano-sized grains of nano-fluorescent ceramics can enhance the scattering of the incident laser, improve the light conversion efficiency of the blue laser, and obtain a high-brightness lighting source. It has great application prospects in the field of realizing high-brightness laser lighting.

[0059] The present invention has been subjected to multiple tests, and some of the test results are cited as references to further describe the invention in detail, which will be described in detail below in conjunction with specific embodiments.

[0060] Example 1

[0061] Step 1: Preparation of Lu element oxide nanopowder

[0062] The Lu2O3 micron powder is dissolved in excess nitric acid, placed in a reactor and reacted in an oven for 24 hours to obtain a reaction solution. After taking out, an appropriate amount of supersaturated ammonium bicarbonate solution is added and stirred until the reaction is complete, so that it is neutralized with the remaining nitric acid in the reaction solution and reacts with the reaction solution to precipitate. The precipitate is centrifuged 3 to 5 times with deionized water or ethanol, placed in an oven for drying, taken out, ground, and moved to a muffle furnace. It is calcined at 900 degrees Celsius for 2 hours to obtain Lu2O3 nanopowder for later use. Figure 3 The powder morphology before and after treatment is shown. It can be seen that the particle size of the powder is significantly reduced after treatment, and nano-scale Lu2O3 powder is successfully prepared.

[0063] Step 2: Preparation of nanomaterial mixture

[0064] According to Lu3Al5O 12 : Ce, weighing Lu2O3 nanopowder, Al2O3 nanopowder and CeO2 according to the stoichiometric ratio, and adding 0.1% of a dispersant and 0.5% of a sintering aid in a ratio of the mass of the raw materials to obtain a nano raw material mixture;

[0065] The nano-raw material mixture is ball-milled for 28 hours to be fully mixed, taken out, dried, ground and sieved to obtain the nano-scale raw material.

[0066] Step 3: Ultra-fast sintering of nano-fluorescent ceramics

[0067] The nanoscale raw materials are dry-pressed into green bodies at a pressure of 40 kilonewtons. The green bodies are placed in a muffle furnace for debinding at 800 degrees Celsius for 8 hours, and then subjected to cold isostatic pressing at 250 MPa. Finally, the green bodies are sintered in situ in a pulsed Joule heat rapid sintering device at 1500-2000 degrees Celsius for less than 20 seconds to obtain nano-fluorescent ceramics.

[0068] After experimental testing:

[0069] When in-situ sintered at 1500-2000 degrees Celsius for less than 10 seconds, the nano-luminescent ceramics produced had a uniformly distributed grain size within 400 nanometers, with a minimum particle size of 80 nanometers.

[0070] When the nano fluorescent ceramics are sintered in situ at 1500-2000 degrees Celsius for 10-15 seconds, the grain size is uniformly distributed between 400 and 700 nanometers.

[0071] When the nano fluorescent ceramics are sintered in situ at 1500-2000 degrees Celsius for 15-20 seconds, the grain size of the prepared nano fluorescent ceramics is uniformly distributed in the range of 700-1000 nanometers.

[0072] Among them, under the extreme sintering conditions where the fluorescent ceramics just sinter into phase, the particle size of the nano fluorescent ceramics is the smallest. Specifically: sintering at 1800 degrees Celsius for 8 seconds, sintering at 1900 degrees Celsius for 6.5 seconds, and sintering at 2000 degrees Celsius for 4 seconds. The morphology of the obtained nano fluorescent ceramics is shown in the figure below. Figure 7 shown.

[0073] Example 2

[0074] The difference from Example 1 is that the nano fluorescent ceramics are obtained by in-situ reaction sintering at 1800 degrees Celsius for 8 seconds.

[0075] Example 3

[0076] The difference from Example 2 is that the in-situ reaction sintering time is 11 seconds.

[0077] Example 4

[0078] The difference from Example 2 is that the in-situ reaction sintering time is 14 seconds.

[0079] Example 5

[0080] The difference from Example 2 is that the in-situ reaction sintering time is 17 seconds.

[0081] Example 6

[0082] The difference from Example 2 is that the in-situ reaction sintering time is 20 seconds.

[0083] Example 7

[0084] The difference from Example 2 is that the in-situ reaction sintering time is 10 seconds. The excitation spectrum and emission spectrum of the prepared nano fluorescent ceramics are shown as follows: Figure 8 and Figure 9 As shown;

[0085] Example 8

[0086] The difference from Example 2 is that the sintering temperature is 1900 degrees Celsius and the in-situ reaction sintering time is 6.5 seconds.

[0087] Example 9

[0088] The difference from Example 2 is that the sintering temperature is 2000 degrees Celsius and the in-situ reaction sintering time is 4 seconds.

[0089] The XRD patterns of the nano fluorescent ceramics obtained in Example 8 and Example 9 are as follows: Figure 10 As shown, the appearance is Figure 7 shown.

[0090] Comparative Example 1

[0091] The difference from Example 2 is that the in-situ reaction sintering time is 25 seconds. The morphology of the prepared fluorescent ceramic is as follows: Figure 11 As shown;

[0092] The nano fluorescent ceramics obtained in Examples 2-6 were tested for internal quantum efficiency, external quantum efficiency and absorptivity. The test results are shown in Table 1.

[0093]

[0094] The XRD patterns, morphology and grain growth curves of the nano fluorescent ceramics obtained in Examples 2-6 are shown in FIG. Figures 4 to 6 As shown, from Figure 4 It can be seen that pure phase fluorescent ceramics can be sintered under different sintering conditions;

[0095] As can be seen from the above, by regulating the sintering temperature and time, nanoluminescent ceramics with particle sizes of 80 to 1000 nanometers can be produced. The nanoscale grains effectively enhance the scattering of incident laser light, thereby improving luminous efficiency. By adjusting the composition of elements A and B, nanoluminescent ceramics of different colors can be obtained. These nanoluminescent ceramics can be effectively excited by blue laser light, and the emission spectrum exhibits broadband fluorescence with a peak wavelength in the 500 to 600 nanometer range.

[0096] The nano-luminescent ceramic, sintered using pulsed Joule heating at 1800 degrees Celsius in 20 seconds, features a microstructure with crystal grain sizes ranging from 80 to 1000 nanometers and an internal quantum efficiency of approximately 90%. Under blue laser excitation, light scattering within the nano-luminescent ceramic microstructure is enhanced, improving the blue light conversion efficiency, reaching a luminous efficacy of 248 lumens per watt.

[0097] The ultra-fast preparation method for nano-luminescent ceramics provided by this invention utilizes nanoscale raw materials and an ultra-rapid thermal shock strategy to achieve in-situ reaction sintering of the nano-luminescent ceramics. This method simplifies the preparation process and accelerates sintering. Furthermore, it achieves high doping of luminescent centers while maintaining constant quantum efficiency, thereby increasing the light saturation threshold of the fluorescent ceramics.

[0098] The nanoluminescent ceramics of this invention offer numerous advantages, including small particle size, high efficiency, excellent luminous efficacy, high light intensity, adjustable color, and long life. Furthermore, the resulting nanoluminescent ceramics possess high thermal conductivity and can be effectively excited by blue laser light. The nanosized grains enhance the scattering of incident laser light, improving the light conversion efficiency of blue laser light and resulting in a high-brightness illumination source. The nanoluminescent ceramics and their preparation methods are expected to be widely used and developed in the field of laser lighting.

[0099] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A nano fluorescent ceramic, characterized in that: The molecular general formula of the nano-fluorescent ceramic is A 3-x B5O 12 : xCe, where element A includes at least one of Y, Lu, Gd, and Tb elements, and element B includes at least one of Al, Mg, and Si elements; among them, when element A contains Lu and other elements, the Lu content is greater than 50%; when element B contains Al and other elements, the Al content is greater than 50%; Ce element replaces part of element A and occupies its lattice site as the luminescence center, where 0 < x ≤ 0.015; the crystal structure of the crystalline phase of the nano-fluorescent ceramic is the same as that of yttrium aluminum garnet, and the crystal particle size range is 80 - 1000 nanometers.

2. The nano fluorescent ceramic according to claim 1, characterized in that: The density of the nano fluorescent ceramic is not less than 95%.

3. The nano fluorescent ceramic according to claim 1, characterized in that: The nano fluorescent ceramic can emit broadband fluorescence with a peak wavelength in the range of 500 to 600 nanometers under the excitation of a blue light source, and the quantum efficiency is not less than 50%.

4. A method for preparing the nano fluorescent ceramic according to any one of claims 1 to 3, characterized in that: include: Preparation of nanoscale raw materials; Nano-fluorescent ceramics are obtained by sintering nano-scale raw materials using an ultra-fast sintering process.

5. The method for preparing the nano fluorescent ceramic according to claim 4, characterized in that: The preparation method of nano-scale raw materials comprises: Preparation of nanopowder of element A oxide: dissolving micron powder of element A oxide in excess nitric acid, placing in a reactor and reacting in an oven for 24 hours to obtain a post-reaction solution, removing the solution, adding an appropriate amount of supersaturated ammonium bicarbonate solution, stirring until the reaction is complete, neutralizing the solution with the remaining nitric acid, and reacting with the post-reaction solution to precipitate, centrifuging 3-5 times with deionized water or ethanol, drying in an oven, removing the solution, grinding it, transferring it to a muffle furnace, and calcining it at 900 degrees Celsius for 2 hours to obtain nanopowder of element A oxide; the nanopowder of element A oxide has a particle size of less than 100 nanometers; Weighing nanopowders of element A oxide, element B oxide, and CeO2 in a stoichiometric ratio, and adding 0.1% of a dispersant and 0.5% of a sintering aid in a mass ratio to the raw materials to obtain a nano raw material mixture; The nano-raw material mixture is ball-milled for 20 to 40 hours to be fully mixed, taken out, dried, ground and sieved to obtain the nano-scale raw material.

6. The method for preparing the nano fluorescent ceramic according to claim 4, characterized in that: Nano-scale raw materials are sintered using ultra-fast sintering technology to produce nano-fluorescent ceramics, including: The nanoscale raw materials are dry pressed to obtain green compacts at a pressure of 20 to 60 kilonewtons. The green body is placed in a muffle furnace for debinding, then subjected to cold isostatic pressing at 250 MPa, and finally placed in a pulsed Joule heat rapid sintering device. Nano-fluorescent ceramics are obtained by in-situ reaction sintering within 20 seconds at a sintering temperature of 1500-2000 degrees Celsius.

7. The method for preparing the nano fluorescent ceramic according to claim 6, characterized in that: The heating and cooling rate of the sintering process used is 100,000 degrees Celsius per second.

8. Use of the nano fluorescent ceramic according to any one of claims 1 to 3 in the field of laser lighting.

Images