Preparation and application of scintillation ceramic powder-silicon oxide aerogel composite luminescent material

Abstract

The application discloses a kind of preparation and application of scintillation ceramic powder silica aerogel composite luminescent material, comprising: with Tb4O7, Al (NO3) 3·9H2O, Gd (NO3) 3·6H2O, Ce (NO3) 3·6H2O and citric acid as raw material, scintillation ceramic powder is prepared using sol-gel method;Tetraethyl orthosilicate, deionized water and ethanol are mixed and stirred, scintillation ceramic powder is added, continue to stir, ammonia is added to catalyze, continue to stir, when it is close to gel state, it is transferred to a suitable mold, and a wet gel is formed, then soaked in ethanol, and then dried using ethanol supercritical, to obtain scintillation ceramic powder silica aerogel composite luminescent material.The scintillation ceramic powder silica aerogel composite luminescent material prepared by the application has good luminescent performance and luminescent thermal stability, high internal quantum efficiency, and can be applied to energy saving and environmental protection, laser lighting and other dual-use fields.

Description

Technical Field

[0001] This invention belongs to the field of silica aerogel preparation technology, and more specifically, this invention relates to the preparation and application of a scintillation ceramic powder@silica aerogel composite luminescent material. Background Technology

[0002] Solid-state lighting devices, represented by light-emitting diodes (LEDs), play a vital role in home lighting, plant lighting, and automotive lighting. However, traditional LED chips are limited by Auger recombination, resulting in severe light decay and unstable light color, significantly restricting their application in ultra-high brightness and ultra-high power lighting and display scenarios. Therefore, laser lighting based on laser diodes (LDs) has attracted considerable attention and shows broad market application potential in special lighting fields such as deep-sea lighting, automotive lighting, and medical lighting. On the one hand, laser components are small, making production easier and more energy-efficient. On the other hand, laser excitation of phosphors is highly efficient, without the "efficiency roll-off" phenomenon. However, current methods of obtaining white light by remotely exciting fluorescent materials using blue or near-ultraviolet LD chips are limited by luminescence saturation and light extraction, thus restricting improvements in luminous efficiency and color stability. Summary of the Invention

[0003] One object of the present invention is to solve at least the above-mentioned problems and / or defects, and to provide at least the advantages described below.

[0004] To achieve these objectives and other advantages of the present invention, a method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material is provided, comprising the following steps:

[0005] Step 1: Heat the HNO3 solution, then add the rare earth oxide Tb4O7 to the HNO3 solution, mix and stir until a colorless and transparent solution is obtained;

[0006] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 2-4 times to remove excess HNO3 until the solution pH is neutral. Then add Al(NO3)3·9H2O, Gd(NO3)3·6H2O, Ce(NO3)3·6H2O and citric acid to the solution and stir. The reaction will produce a pale yellow gel.

[0007] Step 3: Dry the pale yellow gel, grind it into powder, and sinter it at high temperature to obtain scintillation ceramic powder;

[0008] Step 4: Mix tetraethyl orthosilicate, deionized water and ethanol, add scintillation ceramic powder, continue stirring, add ammonia water for catalysis, continue stirring, and when it is close to the gel state, transfer it to a suitable mold to form a wet gel, soak it in ethanol, and then use ethanol supercritical drying to obtain scintillation ceramic powder@silica aerogel composite luminescent material.

[0009] Preferably, in step one, the volume fraction of the HNO3 solution is 40-60%, and the solution is heated to 80-100°C.

[0010] Preferably, in step one, the volume-to-mass ratio of HNO3 solution to Tb4O7 is 20 mL: 0.6–0.8 g; the mixture is stirred and reacted for 0.5–1.5 h.

[0011] Preferably, in step two, the molar ratio of Al(NO3)3·9H2O, Gd(NO3)3·6H2O, Ce(NO3)3·6H2O, citric acid and Tb4O7 in step one is 18~22:6~10:0.05~0.15:30~36:0.8~1.0.

[0012] Preferably, in step two, the stirring is carried out for 0.5 to 1.5 hours; the reaction is carried out at 70 to 90°C for 3 to 4 hours.

[0013] Preferably, in step three, the drying temperature is 130–170°C; the specific method for high-temperature sintering is as follows: heat to 550–650°C at a heating rate of 5–15°C / min and hold for 0.5–1.5 h, then heat to 1400–1600°C and hold for 2–4 h.

[0014] Preferably, in step four, the concentration of ammonia is 1.5–2.5 mol / L; and the volume ratio of tetraethyl orthosilicate, deionized water, ethanol, and ammonia is 1:1:4:0.2–0.3.

[0015] Preferably, in step four, the amount of scintillation ceramic powder added is 5% to 20% of the total mass of tetraethyl orthosilicate and scintillation ceramic powder, wherein the mass of tetraethyl orthosilicate = V 正硅酸乙酯 *0.51, V 正硅酸乙酯 This represents the volume (mL) of tetraethyl orthosilicate.

[0016] Preferably, in step four, the mixture is stirred for 20–40 min; stirring is continued for 0.5–1.5 h; and ethanol is soaked for 20–28 h.

[0017] Preferably, step three further includes pretreatment of the gel before high-temperature sintering. The specific method of pretreatment is as follows: Eu2O3 is dissolved in nitric acid solution, and then the pale yellow gel is cut into cubes and added to the solution. The mixture is stirred for 2-5 minutes, the cubes are taken out, dried, and placed in an ultrasonic levitation device. Under vacuum conditions, the ultrasonic standing wave generator is turned on to make the cubes levitate stably. The high-frequency induction heater is turned on and heated for 10-30 minutes. The cubes are then taken out, washed with deionized water 3-5 times, dried, and ground into powder.

[0018] Preferably, the molar ratio of Eu₂O₃ to Tb₄O₇ in step one is 0.01–0.1:0.8–1.0; the volume fraction of the nitric acid solution is 5–15%; the mass-to-volume ratio of Eu₂O₃ to the nitric acid solution is 0.03–0.05 g:100–150 mL; the dimensions of the cubic block are 3–5 mm * 3–5 mm * 3–5 mm; and the vacuum is 10 °C. -1 ~10 Pa; the temperature of the heat treatment is 500~700℃.

[0019] Application of a scintillation ceramic powder@silica aerogel composite luminescent material prepared by the method described above in laser lighting.

[0020] The present invention has at least the following beneficial effects:

[0021] (1) This invention provides a method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material for laser illumination using tetraethyl orthosilicate as a silicon source and scintillation ceramic powder as a luminescent matrix. Its advantages are that it can improve the thermal stability of the luminescent material and avoid the luminescence intensity decay caused by thermal quenching effect; the silica aerogel particles, as scattering centers, can prevent the laser from directly penetrating the fluorescent material, improve the photoconversion efficiency, and avoid reflection loss at the laser incident interface and total internal reflection loss of the converted light at the exit interface.

[0022] (2) This invention uses the sol-gel method to prepare scintillation ceramic powder with good luminescence performance. The selection of Gd(NO3)3·6H2O and Ce(NO3)3·6H2O makes the fluorescence emission peak located in the yellow light region. The material exhibits yellow luminescence, which is more suitable for the method of mixing blue laser and yellow light to finally synthesize white light in the field of laser lighting, and can achieve more efficient luminescence. In addition, the selection of Gd(NO3)3·6H2O and Ce(NO3)3·6H2O improves the internal quantum yield of luminescence of the material and reduces the loss of converted light during transmission. This is of great help to the application of laser lighting devices. It not only helps to improve the lighting stability of laser lighting devices, but also realizes the energy-saving and environmentally friendly characteristics of laser lighting devices.

[0023] (3) Before high-temperature sintering, the present invention also immerses the gel in a nitric acid solution of Eu2O3 to coat the surface of the gel with Eu, thereby improving its surface defects. After heat treatment, some Eu enters the interior of the material through thermal diffusion and ultrasonic action, improving its microstructure and further improving the internal quantum yield of the material. In addition, ultrasonic suspension heating is used, which makes the heating more uniform, the heating efficiency higher, and there is no pollution, resulting in a purer material.

[0024] (4) The scintillation ceramic powder@silica aerogel composite luminescent material prepared by the present invention has good luminescence performance and luminescence thermal stability, high internal quantum yield, and can be applied to dual-use fields such as energy conservation and environmental protection, laser lighting, etc.

[0025] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0026] Figure 1 The excitation spectrum (emission wavelength 570 nm) of the scintillation ceramic powder prepared in Example 1;

[0027] Figure 2 The emission spectrum (excitation wavelength 465 nm) of the scintillation ceramic powder prepared in Example 1;

[0028] Figure 3 The internal quantum yield of the scintillation ceramic powder prepared in Example 1;

[0029] Figure 4 This is a sample image of the scintillation ceramic powder@silica aerogel composite luminescent material prepared in Example 2 with a 5% doping ratio.

[0030] Figure 5 The internal quantum yield of the 5% doped scintillation ceramic powder@silica aerogel composite luminescent material prepared in Example 2;

[0031] Figure 6 Scanning electron microscope image of the 20% doped scintillation ceramic powder@silica aerogel composite luminescent material prepared in Example 7;

[0032] Figure 7 Comparison of internal quantum yield of scintillation ceramic powder prepared in Example 1 and scintillation ceramic powder@silica aerogel composite luminescent material prepared in Examples 2-7;

[0033] Figure 8 A comparison of the luminescence thermal stability of the scintillation ceramic powder prepared in Example 1 and the 20% doped scintillation ceramic powder@silica aerogel composite luminescent material prepared in Example 7. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0035] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0036] Example 1

[0037] A method for preparing scintillation ceramic powder includes the following steps:

[0038] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0039] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0040] Step 3: Dry the pale yellow gel at 150℃, grind it into powder, heat it to 600℃ at a heating rate of 10℃ / min and hold for 1 hour, then heat it to 1500℃ and hold for 3 hours, and let it cool naturally to obtain scintillation ceramic powder.

[0041] The excitation spectrum (emission wavelength 570 nm) of the scintillation ceramic powder prepared in this embodiment was tested, and the results are as follows: Figure 1 As shown; the emission spectrum (excitation wavelength 465 nm) of the scintillation ceramic powder prepared in this embodiment was tested, and the results are as follows. Figure 2 As shown; the internal quantum yield of the scintillation ceramic powder prepared in this embodiment was tested, with a test blank sample (REF) as a control, and the results are as follows. Figure 3 As shown, its internal quantum yield is 70.14%.

[0042] Example 2

[0043] A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material includes the following steps:

[0044] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0045] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0046] Step 3: Dry the pale yellow gel at 150℃, grind it into powder, heat it to 600℃ at a heating rate of 10℃ / min and hold it for 1 hour, then heat it to 1500℃ and hold it for 3 hours, and let it cool naturally to obtain scintillation ceramic powder.

[0047] Step 4: Mix 3 mL of tetraethyl orthosilicate, 3 mL of deionized water, and 12 mL of ethanol and stir for 30 min. Add 0.0805 g of scintillation ceramic powder and continue stirring for 1 h. Add 0.72 mL of 2 mol / L ammonia water for catalysis and continue stirring. The gelation time is 11 min 32 s. When it is close to the gel state, transfer it to a mold to form a cylindrical wet gel with a diameter of 20 mm and a height of 30 mm. Soak it in ethanol for 24 h, and then use supercritical ethanol drying to obtain a 5% doped scintillation ceramic powder@silica aerogel composite luminescent material. Figure 4 As shown.

[0048] The internal quantum yield of the scintillation ceramic powder@silica aerogel composite luminescent material prepared in this embodiment was tested, with a test blank sample (REF) as a control. The results are as follows: Figure 5 As shown, its internal quantum yield is 92.14%.

[0049] Example 3

[0050] A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material includes the following steps:

[0051] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0052] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0053] Step 3: Dry the pale yellow gel at 150℃, grind it into powder, heat it to 600℃ at a heating rate of 10℃ / min and hold it for 1 hour, then heat it to 1500℃ and hold it for 3 hours, and let it cool naturally to obtain scintillation ceramic powder.

[0054] Step 4: Mix 3 mL of tetraethyl orthosilicate, 3 mL of deionized water, and 12 mL of ethanol and stir for 30 min. Add 0.1240 g of scintillation ceramic powder and continue stirring for 1 h. Add 0.72 mL of 2 mol / L ammonia water for catalysis and continue stirring. The gelation time is 11 min 07 s. When it is close to the gel state, transfer it to a mold to form a cylindrical wet gel with a diameter of 20 mm and a height of 30 mm. Soak it in ethanol for 24 h and then use supercritical ethanol drying to obtain a scintillation ceramic powder@silica aerogel composite luminescent material with a doping ratio of 7.5% and an internal quantum yield of 83.49%.

[0055] Example 4

[0056] A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material includes the following steps:

[0057] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0058] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0059] Step 3: Dry the pale yellow gel at 150℃, grind it into powder, heat it to 600℃ at a heating rate of 10℃ / min and hold it for 1 hour, then heat it to 1500℃ and hold it for 3 hours, and let it cool naturally to obtain scintillation ceramic powder.

[0060] Step 4: Mix 3 mL of tetraethyl orthosilicate, 3 mL of deionized water, and 12 mL of ethanol and stir for 30 min. Add 0.1700 g of scintillation ceramic powder and continue stirring for 1 h. Add 0.72 mL of 2 mol / L ammonia water for catalysis and continue stirring. The gelation time is 10 min 53 s. When it is close to the gel state, transfer it to a mold to form a cylindrical wet gel with a diameter of 20 mm and a height of 30 mm. Soak it in ethanol for 24 h and then use supercritical ethanol drying to obtain a 10% doped scintillation ceramic powder@silica aerogel composite luminescent material with an internal quantum yield of 80.42%.

[0061] Example 5

[0062] A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material includes the following steps:

[0063] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0064] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0065] Step 3: Dry the pale yellow gel at 150℃, grind it into powder, heat it to 600℃ at a heating rate of 10℃ / min and hold it for 1 hour, then heat it to 1500℃ and hold it for 3 hours, and let it cool naturally to obtain scintillation ceramic powder.

[0066] Step 4: Mix 3 mL of tetraethyl orthosilicate, 3 mL of deionized water, and 12 mL of ethanol and stir for 30 min. Add 0.2186 g of scintillation ceramic powder and continue stirring for 1 h. Add 0.72 mL of 2 mol / L ammonia water for catalysis and continue stirring. The gelation time is 12 min 12 s. When it is close to the gel state, transfer it to a mold to form a cylindrical wet gel with a diameter of 20 mm and a height of 30 mm. Soak it in ethanol for 24 h and then use supercritical ethanol drying to obtain a scintillation ceramic powder@silica aerogel composite luminescent material with a doping ratio of 12.5% ​​and an internal quantum yield of 74.41%.

[0067] Example 6

[0068] A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material includes the following steps:

[0069] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0070] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0071] Step 3: Dry the pale yellow gel at 150℃, grind it into powder, heat it to 600℃ at a heating rate of 10℃ / min and hold it for 1 hour, then heat it to 1500℃ and hold it for 3 hours, and let it cool naturally to obtain scintillation ceramic powder.

[0072] Step 4: Mix 3 mL of tetraethyl orthosilicate, 3 mL of deionized water, and 12 mL of ethanol and stir for 30 min. Add 0.2700 g of scintillation ceramic powder and continue stirring for 1 h. Add 0.72 mL of 2 mol / L ammonia water for catalysis and continue stirring. The gelation time is 13 min 25 s. When it is close to the gel state, transfer it to a mold to form a cylindrical wet gel with a diameter of 20 mm and a height of 30 mm. Soak it in ethanol for 24 h and then use supercritical ethanol drying to obtain a scintillation ceramic powder@silica aerogel composite luminescent material with a 15% doping ratio and an internal quantum yield of 70.61%.

[0073] Example 7

[0074] A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material includes the following steps:

[0075] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0076] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0077] Step 3: Dry the pale yellow gel at 150℃, grind it into powder, heat it to 600℃ at a heating rate of 10℃ / min and hold it for 1 hour, then heat it to 1500℃ and hold it for 3 hours, and let it cool naturally to obtain scintillation ceramic powder.

[0078] Step 4: Mix 3 mL of tetraethyl orthosilicate, 3 mL of deionized water, and 12 mL of ethanol and stir for 30 min. Add 0.3825 g of scintillation ceramic powder and continue stirring for 1 h. Add 0.72 mL of 2 mol / L ammonia water for catalysis and continue stirring. The gelation time is 12 min 44 s. When it is close to the gel state, transfer it to a mold to form a cylindrical wet gel with a diameter of 20 mm and a height of 30 mm. Soak in ethanol for 24 h, and then use supercritical ethanol drying to obtain a 20% doped scintillation ceramic powder@silica aerogel composite luminescent material. Its scanning electron microscope image is shown below. Figure 6 As shown, its internal quantum yield is 73.27%.

[0079] Example 8

[0080] A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material includes the following steps:

[0081] Step 1: Heat 20 mL of 50% HNO3 solution to 90°C, then add 0.7149 g of rare earth oxide Tb4O7 to the HNO3 solution, mix and stir for 1 h until a colorless and transparent solution is obtained.

[0082] Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 3 times to remove excess HNO3 until the solution pH is neutral. Then add 7.3549g Al(NO3)3·9H2O, 3.5382g Gd(NO3)3·6H2O, 0.0426g Ce(NO3)3·6H2O and 6.5900g citric acid to the solution and stir for 1 hour. React at 80℃ for 3 hours to obtain a pale yellow gel.

[0083] Step 3: Dissolve 0.0346g Eu2O3 in 100mL of 10% HNO3. After drying the pale yellow gel at 150℃, cut it into 5mm*5mm*5mm cubic blocks and add it to the solution. Stir for 3 minutes, remove the cubic blocks, dry them, and place them in an ultrasonic levitation device. Under a vacuum of 1Pa, turn on the ultrasonic standing wave generator to stabilize the cubic blocks. Turn on the high-frequency induction heater and treat them at 600℃ for 20 minutes. Remove the cubic blocks, wash them four times with deionized water, dry them at 150℃, grind them into powder, heat them to 600℃ at a heating rate of 10℃ / min and hold for 1 hour, then heat them to 1500℃ and hold for 3 hours. Allow them to cool naturally to obtain scintillation ceramic powder.

[0084] Step 4: Mix 3 mL of tetraethyl orthosilicate, 3 mL of deionized water, and 12 mL of ethanol and stir for 30 min. Add 0.0805 g of scintillation ceramic powder and continue stirring for 1 h. Add 0.72 mL of 2 mol / L ammonia water for catalysis and continue stirring. The gelation time is 11 min 15 s. When it is close to the gel state, transfer it to a mold to form a cylindrical wet gel with a diameter of 20 mm and a height of 30 mm. Soak it in ethanol for 24 h and then use supercritical ethanol drying to obtain a 5% doped scintillation ceramic powder@silica aerogel composite luminescent material with an internal quantum yield of 96.38%.

[0085] Compared with Example 2, the scintillation ceramic powder@silica aerogel composite luminescent material of this embodiment has a higher internal quantum yield. This indicates that the present invention coats Eu on the surface of the gel, which improves its surface defects. After heat treatment, some Eu enters the interior of the material through thermal diffusion and ultrasonic action, which improves its microstructure. At the same time, ultrasonic suspension heating is used, which makes the heating more uniform, has higher heating efficiency, and is pollution-free, resulting in a purer material, which is conducive to improving the internal quantum yield of the material.

[0086] The internal quantum yields of the scintillation ceramic powder prepared in Example 1 and the scintillation ceramic powder@silica aerogel composite luminescent materials prepared in Examples 2-7 are as follows: Figure 7 As shown, the different internal quantum yields indicate that there are differences in energy utilization among the samples. It can be seen that the internal quantum yields of the scintillation ceramic powder@silica aerogel composite luminescent materials with different doping ratios of the present invention are all higher than those of the scintillation ceramic powder, indicating that the scintillation ceramic powder@silica aerogel composite luminescent material prepared by the present invention has good luminescent performance, high energy utilization, and high luminescent efficiency.

[0087] The luminescence thermal stability of the scintillation ceramic powder prepared in Example 1 and the 20% doped scintillation ceramic powder@silica aerogel composite luminescent material prepared in Example 7 is as follows: Figure 8 As shown, the scintillation ceramic powder@silica aerogel composite luminescent material of the present invention exhibits superior luminescent thermal stability within the temperature range of 25–300℃.

[0088] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for preparing a scintillation ceramic powder@silica aerogel composite luminescent material, characterized in that, Includes the following steps: Step 1: Heat the HNO3 solution, then add the rare earth oxide Tb4O7 to the HNO3 solution, mix and stir until a colorless and transparent solution is obtained; Step 2: Evaporate the solution to dryness, then add deionized water to dissolve it. Repeat this process 2-4 times to remove excess HNO3 until the solution pH is neutral. Then add Al(NO3)3·9H2O, Gd(NO3)3·6H2O, Ce(NO3)3·6H2O, and citric acid to the solution and stir. The reaction will produce a pale yellow gel. The molar ratio of Al(NO3)3·9H2O, Gd(NO3)3·6H2O, Ce(NO3)3·6H2O, citric acid, and Tb4O7 from Step 1 is 18-22:6-10:0.05-0.15:30-36:0.8-1.

0. Step 3: Dry and grind the pale yellow gel into powder, and sinter it at high temperature to obtain scintillation ceramic powder; the specific method of high temperature sintering is as follows: heat to 550~650℃ at a heating rate of 5~15℃ / min and hold for 0.5~1.5h, then heat to 1400~1600℃ and hold for 2~4h. Step 4: Mix tetraethyl orthosilicate, deionized water and ethanol, add scintillation ceramic powder, continue stirring, add ammonia water for catalysis, continue stirring, and when it is close to the gel state, transfer it to a suitable mold to form a wet gel, soak it in ethanol, and then use ethanol supercritical drying to obtain scintillation ceramic powder@silica aerogel composite luminescent material.

2. The preparation method of the scintillation ceramic powder@silica aerogel composite luminescent material as described in claim 1, characterized in that, In step one, the volume fraction of the HNO3 solution is 40-60%, and it is heated to 80-100℃.

3. The preparation method of the scintillation ceramic powder@silica aerogel composite luminescent material as described in claim 1, characterized in that, In step one, the volume-to-mass ratio of HNO3 solution to Tb4O7 is 20 mL: 0.6~0.8 g; the mixture is stirred and reacted for 0.5~1.5 h.

4. The preparation method of the scintillation ceramic powder@silica aerogel composite luminescent material as described in claim 1, characterized in that, In step two, the mixture is stirred for 0.5 to 1.5 hours; the reaction is carried out at 70 to 90°C for 3 to 4 hours.

5. The preparation method of the scintillation ceramic powder@silica aerogel composite luminescent material as described in claim 1, characterized in that, In step three, the drying temperature is 130~170℃.

6. The preparation method of the scintillation ceramic powder@silica aerogel composite luminescent material as described in claim 1, characterized in that, In step four, the concentration of ammonia is 1.5~2.5 mol / L; the volume ratio of tetraethyl orthosilicate, deionized water, ethanol and ammonia is 1:1:4:0.2~0.

3.

7. The preparation method of the scintillation ceramic powder@silica aerogel composite luminescent material as described in claim 1, characterized in that, In step four, the amount of scintillation ceramic powder added is 5% to 20% of the total mass of tetraethyl orthosilicate and scintillation ceramic powder.

8. The preparation method of the scintillation ceramic powder@silica aerogel composite luminescent material as described in claim 1, characterized in that, In step four, mix and stir for 20-40 minutes; continue stirring for 0.5-1.5 hours; and soak in ethanol for 20-28 hours.

9. The application of a scintillation ceramic powder@silica aerogel composite luminescent material prepared by the preparation method according to any one of claims 1-8 in laser lighting.

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