Green luminescent material and production method thereof

Abstract

The invention discloses a green luminescent material and a production method thereof, and belongs to the field of luminescent materials, and the general chemical formula is Si < 6-z > Al < z > O < z > N < 8-z >: xEu < 2 + >. The luminescent material is formed by multiple times of high-temperature sintering, Eu < 2 + > is introduced by multiple times through each high-temperature sintering, and then a final product is obtained through low-temperature annealing and post-treatment. The prepared green luminescent material has high color purity and luminance, has wide application prospects in preparation of white light LED backlight sources, and is especially applied to ultra-wide color gamut liquid crystal backlight source devices. The sintering process method provided by the invention is suitable for large-scale industrial production of beta-sialon green light-emitting materials with various light-emitting wavelengths; the beta-sialon green luminescent material with high color purity and high brightness is produced by adjusting and controlling process parameters such as a sintering aid, a sintering temperature, a sintering atmosphere, sintering times and the addition amount of Eu < 2 + > during each high-temperature sintering.

Description

Technical Field

[0001] The present invention relates to the field of luminescent materials, and particularly to a green luminescent material and a production method thereof. Background Art

[0002] After being excited by a light source, luminescent materials can emit light in the wavelength range from ultraviolet to infrared. Therefore, light-emitting devices composed of light-emitting diodes (LEDs) and luminescent materials have been widely used in lighting, liquid crystal displays, night vision, and other scenarios. For example, combining luminescent materials in the cyan, green, yellow, orange, and red wavelength bands with blue LEDs can improve the color rendering index of the light-emitting device. Another example is that combining narrow-band emitting green and red luminescent materials with blue LEDs can improve the color gamut of the light-emitting device.

[0003] To improve the stability of luminescent materials and the service life of light-emitting devices, oxynitride luminescent materials have stood out among luminescent materials such as sulfides, aluminates, phosphates, and silicates. Among them, as a silicon nitride solid solution, sialon luminescent materials have two crystal forms. After Eu 2+ doping, they can be used as efficient yellow and green luminescent materials respectively, and can be effectively excited from near-ultraviolet light to blue light. The chemical composition formula of β-sialon is Si 6-z Al z O z N 8-z :Eu 2+ (0 < z ≤ 4.2). As the substitution amount of Al-O for Si-N changes, the rigidity and order degree of the β-sialon crystal structure also change, and then the emission peak position and full width at half maximum also change, ranging from 500 nm to 600 nm. In order to obtain a β-sialon green luminescent material with high color purity, it is necessary to reduce the oxygen content in the crystal structure to cause a blue shift and narrowing of the emission spectrum. However, since the length of the Al-O bond is greater than that of the Si-N bond, as the substitution amount decreases, the reduction of the unit cell parameter also decreases. And the radius of Eu 3+ is smaller than that of Eu 2+ , so it is easier to enter the interstitial position of the β-sialon crystal structure, resulting in a sharp decrease in luminescence brightness. Therefore, the high color purity and high luminescence brightness of β-sialon green luminescent materials are inherent contradictions in its structure itself.

[0004] Currently, β-sialon green luminescent materials generally have the problems of insufficient luminescence brightness and low color purity. According to the currently reported literature: (1) Non-patent literature "Characterization and properties of green-emitting β-SiAlON:Eu 2+"Powder Phosphors for White Light-Emitting Diodes", Hirosaki, T., Xie, R.-J., Kimoto, K., Appl. Phys. Lett. 86, 211905(2004) discloses β-Sialon:Eu synthesized by reacting for 8 h under nitrogen conditions at 1 Mpa and 1900 °C 2+ luminescent material, the axial size and radial size of the particles are 4 μm and 0.5 μm respectively. The smaller particle size results in poor luminescence brightness, and the color coordinate y is only 0.64; (2) The non-patent literature "Luminescent properties of Sialon:Eu 2+ green phosphors synthesized by gas pressured sintering", Ryu, J.H., Park, Y.G., Won, H.S., Suzuki, H., Kim, S.H., Yoon, C., J. Ceram. Soc. Jpn. 116, 389-394(2008) discloses β-Sialon:Eu synthesized by reacting for 2 h under nitrogen conditions at 0.92 Mpa and 2000 °C 2+ luminescent material, the particle length is 3 - 5 μm, the diameter is 0.5 - 1 μm, and the color coordinate y is only 0.65; (3) The non-patent literature "Toward Higher Color Purity and Narrower Emission Band β-sialon:Eu 2+ by Reducing the Oxygen Concentration", Takahashi, K., Xie, R.-J., Hirosaki, N., Electrochem. Solid-State Lett. 14(11), E38-340(2011) discloses β-Sialon:Eu synthesized by holding for 8 h under nitrogen conditions at 1 Mpa and 2000 °C 2+ luminescent material, the particle length is about 4 μm, the diameter is about 0.5 μm, and the color coordinate y is 0.67.

[0005] It can be seen from the above non-patent literature that it is difficult to achieve a β-sialon green luminescent material with high luminescence brightness. According to non-patent literature (3), it can be seen that reducing the Al-O bond in the β-sialon green luminescent material can achieve an improvement in color purity, but the reduction of the Al and O contents also causes the growth of grain size and Eu 2+Doping becomes increasingly difficult, so it is more difficult to improve the color purity of β-sialon green luminescent materials while achieving high luminous brightness. In summary, there is an urgent need to provide a narrow-band emission β-sialon green luminescent material with high color purity and high brightness and its production method. Summary of the Invention

[0006] The purpose of the present invention is to solve the above problems of insufficient luminous brightness and poor color purity of β-sialon green luminescent materials in the prior art, and to provide a green luminescent material and its production method. The green luminescent material is prepared by multiple high-temperature sinterings, low-temperature annealings, and post-treatments, and Eu 2+ is introduced in batches through each high-temperature sintering to ensure that while improving the luminous intensity, the color purity of its luminescence is not affected.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A production method of a green luminescent material, comprising the following steps:

[0009] 1) Mixing of raw materials and fluoride sintering aids: The raw materials include silicon raw materials, aluminum raw materials, and europium raw materials. The above raw materials are ground, mixed, and sieved with fluoride sintering aids; wherein, at least one of the silicon raw materials, aluminum raw materials, and europium raw materials includes nitrides and oxides;

[0010] 2) High-temperature sintering: The above mixture is subjected to the first high-temperature sintering to obtain a primary heat treatment product; after the primary heat treatment product is cooled, it is taken out, ground, and sieved, and then mixed with europium raw materials and subjected to the second high-temperature sintering to obtain a secondary heat treatment product; the secondary heat treatment product is ground, sieved, and then mixed with europium raw materials and subjected to the third high-temperature sintering to obtain a tertiary heat treatment product;

[0011] 3) Annealing treatment: The tertiary heat treatment product is ground, sieved, mixed with europium raw materials, and annealed, cooled, ground, and sieved to obtain an annealed product; or the tertiary heat treatment product is ground, sieved, directly annealed, cooled, ground, and sieved to obtain an annealed product;

[0012] 4) Acid treatment: The annealed product is acid-treated, centrifuged to obtain an acid-treated product; pure water is added to the acid-treated product to adjust the pH, and then it is subjected to multiple ultrasonic and centrifugation treatments, and finally dried to obtain the green luminescent material.

[0013] The silicon raw material is one or more of Si, Si3N4, SiO2, silicate, silicon oxynitride; the aluminum raw material is one or more of Al, AlN, Al2O3, AlCl3, AlF3, Al(OH)3; the europium raw material is one or more of Eu2O3, EuN, Eu(OH)3, EuCl3, EuF3, EuCl2; the fluoride sintering aid includes one or more of CaF2, SrF2, LiF, AlF3, CeF3, EuF3, LaF3, BaF2, NH4F, NaF, MgF2, BeF2. When two aluminum raw materials are mixed, such as Al2O3 and AlN, the molar ratio of the two is in the range of 10:90 to 90:10.

[0014] The added amount of the fluoride sintering aid is 1% to 4% of the mass of the raw material.

[0015] In the mixture of the first high temperature sintering, the stoichiometric ratio of Si:Al:Eu is 5.60~5.97:0.03~0.40:0.004~0.012.

[0016] In the second high-temperature sintering, the mass ratio of the first heat treatment product to the europium raw material is 1:0.001~0.04; in the third high-temperature sintering, the mass ratio of the second heat treatment product to the europium raw material is 1:0.001~0.04.

[0017] In the annealing process of the present invention, when the tertiary heat treatment product is mixed with the europium raw material for annealing, the mass ratio of the tertiary heat treatment product to the europium raw material is 1:0.001-0.04.

[0018] In each sintering (high temperature, low temperature) step, a vacuum sintering step should be included in the heating stage to remove water vapor, O2, impurities, etc. that exist or adhere to the inside of the sintering equipment, the crucible, the surface of the raw material particles, etc. The vacuum sintering temperature range is preferably 400~1000℃.

[0019] The high-temperature sintering temperature is 1800-2200° C., the sintering pressure is not higher than 10 MPa, the high-temperature sintering time each time is 1-20 hours, and the sintering atmosphere is at least one of N2, H2, Ar, He or NH3.

[0020] When the reaction raw materials are sintered at the expected temperature or higher, the activation element Eu can be incorporated into the β-sialon green luminescent material more effectively; when the reaction raw materials are sintered at the expected temperature or lower, the decomposition of the reaction raw materials of the β-sialon green luminescent material can be effectively inhibited. The sintering atmosphere for high-temperature sintering is preferably a gas containing nitrogen, which can inhibit the decomposition of the reaction raw materials of the β-sialon green luminescent material. Since there are high-temperature volatile gases in the reaction raw materials, the higher the atmospheric pressure, the higher the ability to inhibit decomposition. Therefore, from the perspective of long-term use of industrial equipment and manufacturing capacity, the atmospheric pressure is more preferably 0.5~2 Mpa.

[0021] The temperature of the annealing treatment is 600~1800 °C, the pressure of the annealing treatment is not higher than 10 Mpa, the time of the annealing treatment is 1~20 h, and the atmosphere is at least one of N2, H2, Ar, He or NH3. When the heat-treated product is annealed at the expected temperature or higher, the activation element Eu can be incorporated into the β-sialon green luminescent material more effectively, and the unstable phases in the heat-treated product, such as amorphous phase, low-crystalline phase, and impurity phase, can be removed; when the heat-treated product is sintered at the expected temperature or lower, the decomposition of the reaction raw materials of the β-sialon green luminescent material can be effectively inhibited. The annealing atmosphere for low-temperature annealing is preferably a gas containing nitrogen, which can inhibit the decomposition of the reaction raw materials of the β-sialon green luminescent material.

[0022] When the sintering aid is mixed with the reaction raw materials and then sintered, the reaction between the raw materials will be promoted, and the solid-phase reaction process will be easier to proceed. Therefore, it can be considered to be added during the production of the product. The temperature of the high-temperature sintering should be the same as or higher than the temperature at which the substance used as the sintering aid forms a liquid phase, so as to achieve the purpose of promoting the reaction.

[0023] In the present invention, the products that have completed high-temperature sintering and low-temperature annealing are post-treated, including acid treatment, ultrasonic treatment, classification treatment, and drying. The amorphous phase, low-crystalline phase, and impurity phase in the β-sialon green luminescent material are reduced through post-treatment. Specifically, the acid in the acid treatment process is one or several of HF, HNO3, HCl, H2O2, H2SO4, and H2CO3, and preferably a mixed acid solution of HF and HNO3. The acid treatment step should be carried out under heating and stirring conditions, which helps to accelerate the reaction. The heating temperature is preferably 50~100 °C; the acid treatment time is preferably 15~60 minutes. After taking out the β-sialon green luminescent material after acid treatment, pure water is added for washing until the pH is maintained at 6~7, and it is put into an ultrasonic machine for ultrasonic treatment multiple times, 30~60 minutes each time. The upper turbid liquid is continuously sucked away and pure water is added until the upper liquid is clear, and then it is subjected to classification treatment using a centrifuge, and this is repeated 3~5 times to remove the β-sialon green luminescent material with small particle sizes.

[0024] A green luminescent material prepared by the production method, with the chemical general formula Si 6-z Al z O z N 8-z :xEu 2 + , where 0 < z ≤ 0.25, 0 < x ≤ 0.1. The green luminescent material emits fluorescence with a peak within the wavelength range of 500 - 600 nm under ultraviolet or blue light excitation with a wavelength of 250 - 500 nm

[0025] Compared with the prior art, the beneficial effects achieved by the technical solution of the present invention are as follows:

[0026] According to the implementation method of the present invention, a green phosphor with both high color purity and high brightness characteristics can be prepared. The chemical general formula of the phosphor is Si 6-z Al z O z N 8-z :xEu 2+ . The green phosphor uses Eu 2+ as the activator. Under 450 nm blue light excitation, when the external quantum efficiency of luminescence reaches 37.3%, its color purity can reach (0.2466, 0.6999). Therefore, the phosphor can be applied to ultra-wide color gamut white LED backlight devices excited by blue LEDs. The innovation point of the present invention lies in the optimization of luminescence performance. By precisely controlling the chemical composition of Si 6-z Al z O z N 8-z :xEu 2+ and optimizing the sintering process, such as adjusting the proportions of elements such as Si, Al, and Eu, and introducing the luminescence center step by step through multiple sinterings, the luminescence performance of the phosphor can be optimized to meet the application requirements of high resolution and high definition displays. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is the emission spectrum diagram of the green luminescent material prepared in Example 1.

[0028] Figure 2 It is the scanning electron microscope image of the green luminescent material prepared in Example 1.

[0029] Figure 3 It is the X-ray diffraction pattern of the green luminescent material prepared in Example 1.

[0030] Figure 4 It is the emission spectrum diagram of the green luminescent material prepared in Example 44.

[0031] Figure 5Scanning electron microscope image of the green light-emitting material prepared in Example 44. Detailed implementation mode

[0032] 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 the drawings and embodiments.

[0033] Example 1

[0034] The preparation method of the green light-emitting material in this example includes the following steps:

[0035] 1. Weigh silicon, aluminum nitride, aluminum oxide, europium oxide, and sodium fluoride. Among them, the stoichiometric ratio of Si:Al:Eu is 5.93:0.07:0.006, and the stoichiometric ratio of aluminum nitride and aluminum oxide is 0.05:0.02. Sodium fluoride is 2wt% of the sintering raw material quality. Mix them evenly by dry method in an Al2O3 mortar and pass through a 150-mesh sieve, and then transfer them to a boron nitride crucible. High-temperature sinter at 1950 °C under a nitrogen atmosphere (purity > 99.999%) at 0.9 Mpa for 15 h, take it out after natural cooling, grind it into fine powder in an Al2O3 mortar and pass through a 150-mesh sieve to obtain the primary heat treatment product;

[0036] 2. Weigh according to the ratio of adding 0.0034 g of Eu2O3 per gram of the primary heat treatment product, mix evenly by dry method in an Al2O3 mortar and pass through a 150-mesh sieve, and then transfer it to a boron nitride crucible. Perform secondary sintering under the same conditions, take it out after natural cooling, grind it into fine powder in an Al2O3 mortar and pass through a 150-mesh sieve to obtain the secondary heat treatment product;

[0037] 3. Weigh according to the ratio of adding 0.0035 g of Eu2O3 per gram of the secondary heat treatment product, mix evenly by dry method in an Al2O3 mortar and pass through a 150-mesh sieve, and then transfer it to a boron nitride crucible. High-temperature sinter at 1925 °C under a nitrogen atmosphere (purity > 99.999%) at 0.9 Mpa for 15 h, take it out after natural cooling, grind it into fine powder in an Al2O3 mortar and pass through a 150-mesh sieve to obtain the tertiary heat treatment product;

[0038] 4. Transfer the tertiary heat treatment product to a boron nitride crucible, keep it at 1400 °C for 4 h under a nitrogen-hydrogen gas (volume ratio of 95 / 5) atmosphere at atmospheric pressure (0.1 Mpa). Subsequently, during the process of cooling to room temperature, keep it at 1100 °C for another 4 h, take it out after natural cooling, grind it into fine powder in an Al2O3 mortar and pass through a 150-mesh sieve to obtain the annealed product;

[0039] 5. Place the annealed product in a container, add hydrofluoric acid (HF, 50%) and nitric acid (HNO3, 68%) into the container according to the mass ratio of 1:1, mix with the annealed product, and perform acid treatment at 75 °C and 450 rpm / min for 30 min. After centrifugation, take out the acid-treated product;

[0040] 6. Place the acid-treated product in a container, add pure water until the pH = 6 - 7, then perform ultrasonic treatment for 30 min each time, and remove the upper turbid liquid until the upper liquid is clear during each ultrasonic interval. Then perform fractionation treatment, and centrifuge three times at 2000 rpm / min to obtain the fractionated product;

[0041] 7. Place the fractionated product in a container, place it in an electrothermal blast drying oven, heat to 80 °C, and dry overnight to obtain a narrow-band emission β - sialon green luminescent material with high color purity and high brightness, Figure 1 , Figure 2 and Figure 3 are the emission spectrum, scanning electron microscope image and X-ray diffraction pattern of the β - sialon green luminescent material respectively.

[0042] Examples 2 - 6

[0043] Except for not adding sodium fluoride or replacing it with other sintering aids, the production methods of the green luminescent materials in Examples 2 - 7 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Examples 1 - 7 were tested, and the results are shown in Table 1. From the results in Table 1, it can be seen that when NaF is added as a sintering aid, a β - sialon green luminescent material with both the best external quantum efficiency and the best luminescence color purity can be obtained.

[0044] Table 1

[0045]

[0046] Examples 7 - 9

[0047] Except for changing the mass ratio of the added sintering raw materials to sodium fluoride, the production methods of the green luminescent materials in Examples 7 - 9 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Example 1 and Examples 7 - 9 were tested, and the results are shown in Table 2. From the results in Table 2, it can be seen that when the addition amount of the sintering aid NaF accounts for 2% of the mass of the sintering raw materials, a β - sialon green luminescent material with both the best external quantum efficiency and the best luminescence color purity can be obtained.

[0048] Table 2

[0049]

[0050] Examples 10 - 12

[0051] Except for changing the sintering temperature of the high-temperature sintering once, the production methods of the green luminescent materials in Examples 10 - 12 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Example 1 and Examples 10 - 12 were tested, and the results are shown in Table 3. It can be seen from the results in Table 3 that when the sintering temperature is 1950 °C, β - sialon green luminescent materials with both the best external quantum efficiency and the best luminescence color purity can be obtained.

[0052] Table 3

[0053]

[0054] Examples 13 - 20

[0055] Except for changing the mass ratio of the primary heat treatment product to Eu2O3, the production methods of the green luminescent materials in Examples 13 - 20 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Example 1 and Examples 13 - 20 were tested, and the results are shown in Table 4. It can be seen from the results in Table 4 that when the mass ratio of Eu2O3 to the primary heat treatment product is 0.0034 g / g, β - sialon green luminescent materials with both the best external quantum efficiency and the best luminescence color purity can be obtained.

[0056] Table 4

[0057]

[0058] Examples 21 - 28

[0059] Except for changing the mass ratio of the secondary heat treatment product to Eu2O3, the production methods of the green luminescent materials in Examples 21 - 28 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Example 1 and Examples 21 - 28 were tested, and the results are shown in Table 5. It can be seen from the results in Table 5 that when the mass ratio of Eu2O3 to the secondary heat treatment product is 0.0035 g / g, β - sialon green luminescent materials with both the best external quantum efficiency and the best luminescence color purity can be obtained.

[0060] Table 5

[0061]

[0062] Examples 29 - 36

[0063] Except for changing the mass ratio of the product of three heat treatments to Eu2O3, the production methods of the green luminescent materials in Examples 29 to 36 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Example 1 and Examples 29 to 36 were tested, and the results are shown in Table 6. From the results in Table 6, it can be seen that when the mass ratio of Eu2O3 to the product of three heat treatments is 0 g / g, a β-sialon green luminescent material with both the best external quantum efficiency and the best luminescence color purity can be obtained.

[0064] Table 6

[0065]

[0066] Examples 37 - 40

[0067] Except for changing the annealing atmosphere of the low-temperature annealing, the production methods of the green luminescent materials in Examples 37 to 40 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Example 1 and Examples 37 to 40 were tested, and the results are shown in Table 7. From the results in Table 7, it can be seen that when the annealing atmosphere of the low-temperature annealing is nitrogen / hydrogen, a β-sialon green luminescent material with both the best external quantum efficiency and the best luminescence color purity can be obtained.

[0068] Table 7

[0069]

[0070] Examples 41 - 48

[0071] Except for changing the stoichiometric ratio of Si:Al:Eu in the primary sintering raw materials, the production methods of the green luminescent materials in Examples 41 to 48 are the same as those in Example 1. The quantum efficiency and luminescence color purity of the green luminescent materials prepared in Example 1 and Examples 41 to 48 were tested, and the results are shown in Table 8. From the results in Table 8, it can be seen that when the stoichiometric ratio of Si:Al:Eu in the primary sintering raw materials is 5.93:0.07:0.006, a β-sialon green luminescent material with both high external quantum efficiency and high luminescence color purity can be obtained. Figure 4 and Figure 5 are the emission spectrum and scanning electron microscope image of the β-sialon green luminescent material of Example 44, respectively.

[0072] Table 8

[0073]

[0074] In summary, a green phosphor with both high color purity and high brightness characteristics can be prepared according to the implementation method of the present invention. The chemical general formula of the phosphor is Si 6-z Al z Oz N 8-z : xEu 2+ This green phosphor uses Eu 2+ as an activator. When excited by 450 nm blue light, its color purity can reach (0.2466, 0.6999) when the external quantum efficiency of luminescence reaches 37.3%. Thus, this phosphor can be applied to ultra-wide color gamut white LED backlight devices excited by blue LEDs. The innovation of this invention lies in the optimization of luminescence performance. By precisely controlling the chemical composition of Si 6-z Al z O z N 8-z : xEu 2+ and optimizing the sintering process, such as adjusting the ratios of elements such as Si, Al, Eu, etc. and by sintering multiple times and gradually introducing luminescence centers, the optimization of the luminescence performance of the phosphor can be achieved to meet the application requirements of high resolution and high definition displays.

Claims

1. A production method of a green light-emitting material, characterized in that, It includes the following steps: 1) Mixing of raw materials and fluoride sintering aids: The raw materials include silicon raw materials, aluminum raw materials and europium raw materials. The above raw materials are ground, mixed and sieved with fluoride sintering aids; wherein, at least nitride and oxide are included in the silicon raw materials, aluminum raw materials and europium raw materials; 2) High-temperature sintering: The above mixture is sintered at high temperature for the first time to obtain a primary heat treatment product; after the primary heat treatment product is cooled, it is taken out, ground and sieved, then mixed with europium raw materials, and sintered at high temperature for the second time to obtain a secondary heat treatment product; the secondary heat treatment product is ground and sieved, then mixed with europium raw materials, and sintered at high temperature for the third time to obtain a tertiary heat treatment product; 3) Annealing treatment: The tertiary heat treatment product is ground and sieved, then mixed with europium raw materials for annealing treatment, cooled, ground and sieved to obtain an annealed product; or the tertiary heat treatment product is ground and sieved and directly annealed, cooled, ground and sieved to obtain an annealed product; 4) Acid treatment: The annealed product is treated with acid, centrifuged to obtain an acid-treated product; then pure water is added to the acid-treated product to adjust the pH, and then it is subjected to multiple ultrasonic and centrifugation treatments, and finally dried to obtain the green luminescent material.

2. The production method of the green light-emitting material according to claim 1, wherein: The silicon raw material is one or more of Si single substance, Si3N4, SiO2, silicate, silicon oxynitride; the aluminum raw material is one or more of Al single substance, AlN, Al2O3, AlCl3, AlF3, Al(OH)3; the europium raw material is one or more of Eu2O3, EuN, Eu(OH)3, EuCl3, EuF3, EuCl2; the fluoride sintering aids include one or more of CaF2, SrF2, LiF, AlF3, CeF3, EuF3, LaF3, BaF2, NH4F, NaF, MgF2, BeF2.

3. The production method of the green light-emitting material according to claim 1, characterized in that: The addition amount of the fluoride sintering aids is 1% - 4% of the mass of the raw materials.

4. The production method of the green light-emitting material according to claim 1, characterized in that: In the mixture of the first high-temperature sintering, the stoichiometric ratio of Si:Al:Eu is 5.60 - 5.97:0.03 - 0.40:0.004 - 0.

012.

5. The production method of the green light-emitting material according to claim 1, characterized in that: In the second high-temperature sintering, the mass ratio of the primary heat treatment product to the europium raw material is 1:0.001 - 0.04; in the third high-temperature sintering, the mass ratio of the secondary heat treatment product to the europium raw material is 1:0.001 - 0.

04.

6. The production method of the green light-emitting material according to claim 1, characterized in that: In the annealing treatment, when the tertiary heat treatment product is mixed with the europium raw material for annealing treatment, the mass ratio of the tertiary heat treatment product to the europium raw material is 1:0.001 - 0.

04.

7. The production method of the green light-emitting material according to claim 1, characterized in that: The temperature of the high-temperature sintering is 1800 - 2200 °C, the sintering pressure is not higher than 10 Mpa, the time of each high-temperature sintering is 1 - 20 h, and the sintering atmosphere is at least one of N2, H2, Ar, He or NH3.

8. The production method of the green light-emitting material according to claim 1, characterized in that: The temperature of the annealing treatment is 600 - 1800 °C, the pressure of the annealing treatment is not higher than 10 Mpa, the time of the annealing treatment is 1 - 20 h, and the atmosphere is at least one of N2, H2, Ar, He or NH3.

9. A green luminescent material prepared by the production method according to any one of claims 1 - 8.

10. The green light-emitting material according to claim 9, characterized in that: Its chemical general formula is Si 6-z Al z O z N 8-z :xEu 2+ , where 0 < z ≤ 0.25 and 0 < x ≤ 0.1.

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