Near-zero thermal quenching efficient red fluorescent silicate material as well as preparation method and application thereof

Abstract

The invention discloses a near-zero thermal quenching efficient red fluorescent silicate material and a preparation method and application thereof, the chemical formula of the near-zero thermal quenching efficient red fluorescent silicate material is Ba5Y12 (1-x) Zn [O (SiO4)] 8: xEu < 3 + >, and x is equal to 0.00-0.50. The method is simple and convenient, and the prepared fluorescent powder has excellent luminescence performance and thermal stability. Under excitation of near ultraviolet of 394 nm, preferably Ba5Y12 (1-0.25) Zn [O (SiO4)] 8: 0.25 Eu < 3 + > shows high thermal stability of 97% at 150 DEG C / 95% at 200 DEG C and internal quantum efficiency of 94.3%. By combining the red fluorescent powder with other commercial fluorescent powder, a white light LED based on the red fluorescent powder can obtain stable white light emission and excellent color rendering performance.

Description

Technical Field

[0001] This application relates to the technical field of fluorescent materials, in particular to a highly efficient red fluorescent silicate material with near-zero thermal quenching, its preparation method, and applications. Background Art

[0002] Currently, white light-emitting diodes (WLEDs) have been widely used in the fields of lighting and display. However, their luminous efficiency and luminous quality still face challenges. Traditional WLEDs use GaN blue LEDs to excite yellow fluorescent materials to produce white light emission. However, the white light obtained by this method has problems such as low color rendering index (R a ), high correlated color temperature (CCT), etc. In addition, the unabsorbed blue light generated by WLEDs can damage human health. For example, if humans are exposed to short-wave blue light for a long time, it will cause symptoms such as visual fatigue, damage to eye tissues, and decreased sleep quality. To solve this problem, researchers have proposed a solution of ultraviolet light-excited red, green, and blue trichromatic phosphors to solve the blue light hazard, reduce the CCT, and improve the R a . However, due to the low luminous efficiency of existing red phosphors and the large influence of the luminous performance of red phosphors on temperature, the light sources of ultraviolet light-excited red, green, and blue trichromatic phosphors have problems of thermal quenching and unstable luminous color.

[0003] Therefore, developing a red fluorescent material that can be effectively excited by near-ultraviolet light and has suitable preparation conditions is of great significance for further optimizing the performance of WLEDs.

[0004] For example, CN202310662543.9 discloses a fluorescent material that can stably and efficiently emit far red light, and its chemical formula is (La 1-x-y-t Ln x Bi y Sr 1+t )(Sc 1-t Mn t )O 4 , where: 0 < x < 0.02, 0 < y < 0.02, 0 < t < 0.02; this material can solve the disadvantages of traditional oxide red fluorescent materials with Mn 4+ as the activator, such as low luminous efficiency and poor fluorescence thermal stability. This material emits far red light in the wavelength range of 650 nm to 750 nm under excitation by near-ultraviolet light with a wavelength of 320 nm. However, the internal quantum efficiency of this material's luminescence is about 50.28% and the excitation light source does not match the currently commercially available high-efficiency near-ultraviolet luminescent materials.

[0005] Rare earth Eu 3+ is an important activator ion with red light emission, and its emission spectrum mainly originates from the excited state within the 4f 6 electron configuration 5D 0 to the low energy level 7 F1, 7 F2 and 7 the energy level transitions of F4. Due to the shielding effect of the outer 5s 2 and 5p 6 shells, the 4f shell electrons are little affected by the crystal field. However, when Eu 3+ ions occupy the inversion center in the matrix, its emission spectrum will be mainly 5 D 0 → 7 F 1 magnetic dipole transitions, emitting orange-red light at about 595 nm. When Eu 3+ ions occupy the asymmetric center lattice sites, it will be mainly 5 D 0 → 7 F 2 electric dipole transitions, emitting red light at about 613 nm.

[0006] In addition, recent literature reports that when Eu 3+ ions occupy the tetragonal antiprismatic configuration with 8 coordination, 7 F 4 can achieve strong emission. However, most of the reported Eu 3+ -doped red fluorescent materials in recent years are low-concentration doped, resulting in low luminous efficiency and poor temperature stability, which limits their practical applications in WLEDs. For example, CN202210011849.3 discloses a borotellurite-based red fluorescent material, and the chemical general formula of this material is: Na 2 Y 2-x TeB 2 O 10 :xRE, RE is Eu 3+ or Sm 3+ , 0.01 ≤ x ≤ 0.7; the used matrix is Na 2 Y 2-x TeB 2 O 10 , when RE = 0.5Eu 3+ in this material, the internal quantum efficiency of the phosphor is 83.7%, but it still faces the challenge of efficient and stable red emission.

[0007] The matrix structure is crucial for the doping concentration, temperature stability, and luminescence quantum efficiency. In previous reports, various cation sites, large cation spacing, and high structural stability have shown positive effects on thermally quenching-resistant and high-quantum-efficiency luminescence.

[0008] Ba 5 Y 12 Zn[O(SiO4 )] 8 As a new type of silicate material system, it has excellent thermal stability, chemical stability and good optical properties, showing broad application prospects in the field of WLED.

[0009] Ba 5 Y 12 Zn[O(SiO 4 )] 8 The crystal structure includes [BaO 8 , [YO 7 , [ZnO 4 and [SiO 4 polyhedral environments, and these polyhedra form a stable network structure through the form of sharing or vertex connection. In addition, in this structure, the [YO 7 polyhedron is further divided by other metal cations, increasing the anti-concentration quenching ability of this material. Therefore, Ba 5 Y 12 Zn[O(SiO 4 )] 8 has the potential to be used as a candidate host material for Eu 3+ -doped high-efficiency red phosphors.

[0010] The information disclosed in the background art section is only intended to enhance the overall understanding of the present invention and should not be regarded as an admission or any form of implication that this information constitutes the prior art known to those of ordinary skill in the art. Summary of the Invention

[0011] The present application provides a high-efficiency red fluorescent silicate material with near-zero thermal quenching, its preparation method and application. A series of Ba 5 Y 12(1-x) Zn[O(SiO 4 )] 8 :xEu 3+ , x = 0.00 - 0.50 red phosphors are prepared by the high-temperature solid-state method.

[0012] The present application provides a high-efficiency red fluorescent silicate material with near-zero thermal quenching, and its chemical formula is Ba 5 Y 12(1-x) Zn[O(SiO 4 )] 8 :xEu 3+ , x = 0.00 - 0.50;

[0013] Specifically, x can also be 0.08, 0.17, 0.25, 0.33, 0.42, 0.50;

[0014] Preferably, x = 0.25.

[0015] Preferably, the chemical formula is Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ .

[0016] Preferably, during the temperature change from 25°C to 200°C, the emission spectra at different temperatures are basically the same; at 150°C and 200°C, the luminescence integral intensities of the samples obtained in Example 1 can maintain 97% and 95% at room temperature; the chromaticity coordinate values are (0.6586, 0.3401).

[0017] Another aspect of the present application also provides a preparation method of an efficient red fluorescent silicate material with near-zero thermal quenching, including the following steps:

[0018] Take the raw materials, mix them, grind them, pre-sinter them, raise the temperature and then carry out solid-phase reaction to obtain the red fluorescent powder with high temperature change stability as described above.

[0019] Preferably, the raw materials are Ba source, Y source, Zn source, Si source, Li source; or the raw materials are Ba source, Y source, Zn source, Si source, Li source, Eu source;

[0020] Preferably, the Ba source is BaCO 3 ; the Y source is Y 2 O 3 ; the Zn source is ZnO; the Si source is SiO 2 ; the Li source is LiCO 3 ; the Eu source is Eu 2 O 3 .

[0021] Preferably, the pre-sintering is carried out at 350 - 450°C for 20 - 30 h, and the heating rate of the pre-sintering is 4 - 6°C / min;

[0022] Preferably, after the pre-sintering, the sample is cooled to room temperature and then ground again for 25 - 35 min.

[0023] Specifically, the pre-sintering is carried out at 400°C for 24 h, and the heating rate of the pre-sintering is 5°C / min; after the pre-sintering, the sample is cooled to room temperature and then ground again for 30 min.

[0024] Preferably, the solid-phase reaction is to heat from room temperature to 1100 - 1200°C at a heating rate of 4 - 6°C / min, and hold at 1100 - 1200°C for 20 - 30 h, and then cool to room temperature at a cooling rate of 4 - 6°C / min.

[0025] Specifically, the solid-phase reaction is to heat from room temperature to 1170 °C at a heating rate of 5 °C / min and hold at 1170 °C for 24 h, and then cool to room temperature at a cooling rate of 5 °C / min.

[0026] Another aspect of the present application also provides an ultraviolet light-excited red, green, and blue trichromatic phosphor composition, including: the high-efficiency red fluorescent silicate material with near-zero thermal quenching as described above.

[0027] Another aspect of the present application also provides a WLED, including: the phosphor as described above.

[0028] The beneficial effects that the present application can produce include:

[0029] 1) The present application provides a preparation method of a high-efficiency red fluorescent silicate material with near-zero thermal quenching. This method is simple and convenient, and the prepared phosphor has high luminescence performance and stability.

[0030] 2) For the preparation method of the high-efficiency red fluorescent silicate material with near-zero thermal quenching provided by the present application, the best-concentration sample Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ shows ultra-high thermal stability and internal quantum efficiency. Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ phosphor has ultra-high luminous efficiency, and its internal quantum efficiency is as high as 94.3%. At the same time, the integrated emission intensity at 150 °C and 200 °C can maintain 97% and 95% of that at room temperature, showing the performance of near-zero thermal quenching; during the change process from 25 °C to 200 °C, the emission spectra are basically the same, and the color coordinate values are (0.6586, 0.3401). BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the XRD pattern of Ba 5 Y 12(1-x) Zn[O(SiO 4 )] 8 :xEu 3+ (x = 0.00 - 0.50) in Examples 1, 2, 3, 4, 5, 6, and 7 of the present invention;

[0032] Figure 2 This is the substance Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8: 0.25Eu 3+ Excitation and emission spectra.

[0033] Figure 3 For the Ba obtained in Examples 1, 3, 4, 5, 6, and 7 in the present invention 5 Y 12(1-x) Zn[O(SiO 4 )] 8 :xEu 3+ (x = 0.00 - 0.50), the emission spectrum obtained under excitation by incident light with a wavelength of 394 nm. The broken line graph b in the figure is the trend graph of the change in the integrated emission intensity with the change in the Eu doping concentration; 3+ ;

[0034] Figure 4 For the material Ba obtained in Example 1 of the present invention 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 : 0.25Eu 3+ Quantum efficiency graph;

[0035] Figure 5 For the spectral integrated intensity change graph of the material obtained in Example 1 of the present invention; where a) is the trend of the emission intensity of the material with temperature change; b) is the trend of the change in the spectral integrated intensity of the material with temperature change;

[0036] Figure 6 For the material Ba obtained in Example 1 of the present invention 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 : 0.25Eu 3+ Chromaticity coordinate graph and electroluminescence spectrum graph; where a) is the chromaticity coordinate graph of the material; b) is the electroluminescence spectrum graph of the WLED device prepared by combining this red phosphor with commercial blue and green phosphors (Illustration I is the physical diagram of the device without power supply; Illustration II is the light - emitting state diagram of the device under power supply); Detailed implementation manners

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited in any way. Any transformation or improvement made based on the teachings of the present invention falls within the protection scope of the present invention.

[0038] Embodiment

[0039] In the following embodiments, the materials and instruments used are obtained from commercial channels without special instructions; the detection methods used are existing methods without special instructions.

[0040] Embodiment 1 Preparation of Ba 5Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ Phosphor

[0041] (1) Weighing: Accurately weigh 0.6578 g of BaCO 3 (AR), 0.6774 g of Y 2 O 3 (99.99%), 0.0543 g of ZnO (99.99%), 0.3204 g of SiO 2 (AR), 0.0320 g of LiCO 3 (99.99%), 0.3519 g of Eu 2 O 3 (99.99%).

[0042] (2) Grinding: Mix the weighed raw materials in an agate mortar and grind for 30 min to fully disperse, then put the reactants into a corundum crucible.

[0043] (3) Pre-sintering: Place the corundum crucible containing the reactants into a muffle furnace and pre-sinter at 400 °C for 24 h; the heating rate is 5 °C / min. After the sample cools to room temperature, grind it again for 30 min.

[0044] (4) Solid-state reaction: Heat the sample after re-grinding from room temperature to 1170 °C at a heating rate of 5 °C / min and hold at this temperature for 24 h. Then, cool it to room temperature at a cooling rate of 5 °C / min. Finally, grind the sample to obtain the final product for subsequent characterization.

[0045] Example 2 Preparation of Ba 5 Y 12 Zn[O(SiO 4 )] 8 Matrix material

[0046] The preparation process is the same as that of Example 1, except that: The specific raw materials and their amounts in Example 2 are 0.6578 g of BaCO 3 (AR), 0.9032 g of Y 2 O 3 (99.99%), 0.0543 g of ZnO (99.99%), 0.3204 g of SiO 2 (AR), 0.0320 g of LiCO 3 (99.99%).

[0047] Example 3 Preparation of Ba 5 Y 12(1-0.08) Zn[O(SiO4 )] 8 : 0.08 Eu 3+ Phosphor

[0048] The preparation process is the same as that of Example 1, except that: the specific raw materials and their amounts used in Example 3 are 0.6578 g of BaCO 3 (AR), 0.8280 g of Y 2 O 3 (99.99%), 0.0543 g of ZnO (99.99%), 0.3204 g of SiO 2 (AR), 0.0320 g of LiCO 3 (99.99%), 0.1173 g of Eu 2 O 3 (99.99%).

[0049] Example 4 prepares Ba 5 Y 12(1-0.17) Zn[O(SiO 4 )] 8 : 0.17 Eu 3+ Phosphor

[0050] The preparation process is the same as that of Example 1, except that: the specific raw materials and their amounts used in Example 4 are 0.6578 g of BaCO 3 (AR), 0.7527 g of Y 2 O 3 (99.99%), 0.0543 g of ZnO (99.99%), 0.3204 g of SiO 2 (AR), 0.0320 g of LiCO 3 (99.99%), 0.2346 g of Eu 2 O 3 (99.99%).

[0051] Example 5 prepares Ba 5 Y 12(1-0.33) Zn[O(SiO 4 )] 8 : 0.33 Eu 3+ Phosphor

[0052] The preparation process is the same as that of Example 1, except that: the specific raw materials and their amounts used in Example 5 are 0.6578 g of BaCO 3 (AR), 0.6022 g of Y 2 O 3 (99.99%), 0.0543 g of ZnO (99.99%), 0.3204 g of SiO 2 (AR), 0.0320 g of LiCO3 (99.99%) and 0.4692 g of Eu 2 O 3 (99.99%).

[0053] Example 6 Preparation of Ba 5 Y 12(1-0.42) Zn[O(SiO 4 )] 8 : 0.42Eu 3+ phosphor

[0054] The preparation process is the same as that of Example 1, except that: the specific raw materials and their dosages in Example 6 are 0.6578 g of BaCO 3 (AR), 0.5269 g of Y 2 O 3 (99.99%), 0.0543 g of ZnO (99.99%), 0.3204 g of SiO 2 (AR), 0.0320 g of LiCO 3 (99.99%), 0.5866 g of Eu 2 O 3 (99.99%).

[0055] Example 7 Preparation of Ba 5 Y 12(1-0.50) Zn[O(SiO 4 )] 8 : 0.50Eu 3+ phosphor

[0056] The preparation process is the same as that of Example 1, except that: the specific raw materials and their dosages in Example 7 are 0.6578 g of BaCO 3 (AR), 0.4516 g of Y 2 O 3 (99.99%), 0.0543 g of ZnO (99.99%), 0.3204 g of SiO 2 (AR), 0.0320 g of LiCO 3 (99.99%), 0.7039 g of Eu 2 O 3 (99.99%).

[0057] Example 8

[0058] The differences from Example 1 are as follows: The pre-sintering is carried out at 350 °C for 20 h, and the heating rate of the pre-sintering is 4 °C / min; the solid-phase reaction is to heat from room temperature to 1100 °C at a heating rate of 4 °C / min and hold at 1100 °C for 20 h, and then cool to room temperature at a cooling rate of 4 °C / min. After pre-sintering, the sample is ground again for 25 min after cooling to room temperature.

[0059] Example 9

[0060] The differences from Example 1 are as follows: The pre-sintering is carried out at 450 °C for 30 h, and the heating rate of the pre-sintering is 6 °C / min; the solid-phase reaction is to heat from room temperature to 1200 °C at a heating rate of 6 °C / min and hold at 1200 °C for 30 h, and then cool to room temperature at a cooling rate of 6 °C / min. After pre-sintering, the sample is ground again for 35 min after cooling to room temperature.

[0061] Detection and analysis:

[0062] 1. The materials obtained in Examples 1-7 are subjected to XRD detection by the existing method, and the XRD patterns are as Figure 1 shown. It can be seen from the figure that Ba 5 Y 12(1-x) Zn[O(SiO 4 )] 8 :xEu 3+ , x = 0.00-0.50 substances are prepared in Examples 1-7. All samples are completely corresponding to the simulated diffraction peaks of Ba 5 Y 12 Zn[O(SiO 4 )] 8 , indicating that all the samples prepared and synthesized are of pure phase structure.

[0063] 2. The excitation and emission detection are carried out on Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ obtained in Example 1, and the results are as Figure 2 shown. It can be seen from the figure that a series of characteristic excitation peaks of Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ are obtained at a monitoring wavelength of 613 nm ( Figure 2 left figure). Including the 7 F 0 → 5 D 1 transition at 534 nm, the7 F 0 → 5 D 2 transition at 394 nm 7 F 0 → 5 L 6 transition at 381 nm 7 F 0 → 5 L 7 transition at 361 nm 7 F 0 → 5 D 4 transition and at 320 nm 7 F 0 → 5 H 3 transition. In addition, the 200 - 300 nm band is the charge transfer band (CTB) from O 2- to Eu 3+ ions. Among them, the 7 F 0 → 5 L 6 transition is the best excitation. Therefore, a series of characteristic emission peaks of Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ were recorded by using 394 nm as the excitation light source, corresponding to the 3+ D 5 → 0 F 7 (580 nm), 0 D 5 → 0 F 7 (592 nm), 1 D 5 → 0 F 7 (613 / 624 nm), 2 D 5 → 0 F 7 (654 nm), and 3 D 5 → 0 F 7 (709 nm) transitions of Eu ions. Among them, the 4 D 5 → 0 F 7 electric dipole transition at 613 nm occupies the main emission, indicating Eu 2 3+ ​Ions in Ba 5 Y 12 Zn[O(SiO 4 )] 8 mainly occupy the non-inversion symmetric center lattice sites. In addition, the optimal excitation of this material is 394 nm, which coincides with the emission spectrum of commercial near-ultraviolet chips and can be used as a material for commercial near-ultraviolet chips.

[0064] 3. The emission spectra of Examples 1, 3, 4, 5, 6, 7 Ba 5 Y 12(1-x) Zn[O(SiO 4 )] 8 :xEu 3+ (x = 8 - 50%) under 394 nm excitation are obtained, and the results are as Figure 3 shown. It can be seen from Figure 3 that as the doping concentration of Eu 3+ increases, the emission spectrum continuously enhances and reaches the highest at 0.25 Eu 3+ concentration doping, and then the emission intensity decreases with the increase of Eu 3+ doping concentration; this indicates that the optimal doping concentration of Eu 5 Y 12 Zn[O(SiO 4 )] 8 in the matrix system is 0.25. 3+

[0065] 4. The quantum efficiency of Example 1 obtained Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ is detected, and the results are as Figure 4 shown; it can be seen from the figure that under 394 nm excitation, the internal quantum efficiency of Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ is 94.3%, the absorption is 21.8%, and the external quantum efficiency is 20.6%.

[0066] 5. The emission intensity of the material of Example 1 obtained Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ with temperature change is detected, and the obtained trend graph is as Figure 5As shown in (a), it can be seen from the above figure that under the excitation of 394 nm, during the temperature change from 25 °C to 200 °C, the emission spectra at different temperatures are basically the same, indicating that the emission intensity of Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ has excellent temperature stability.

[0067] For the Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ material obtained in Example 1, the spectral integrated intensity detection with temperature change was carried out, and the obtained change trend is as Figure 5 shown in (b). It can be seen from the above figure that at 150 °C and 200 °C, the luminescence integrated intensity of the sample obtained in Example 1 can maintain 97% and 95% at room temperature, close to zero thermal quenching, and has good stability of luminescence integrated intensity at high temperature.

[0068] 6. For the Ba 5 Y 12(1-0.25) Zn[O(SiO 4 )] 8 :0.25Eu 3+ material in Example 1, chromaticity coordinate detection was carried out, and the obtained results are as Figure 6 shown in (a). The chromaticity coordinates (x, y) being (0.6586, 0.3401) indicate that the emission color of the prepared material is in the standard red light region. The red-emitting phosphor obtained in Example 1, commercial blue powder (BaMgAl 10 O 17 :Eu 2+ ) and green powder (Ba 2 SiO 4 :Eu 2 + ) were mixed according to the requirements of the existing fluorescent powder preparation formula for WLED devices. After directly mixing the mixed fluorescent powder with epoxy resin in the proportion required by the existing test, the obtained mixture was evenly coated on a 395 nm UV chip to obtain a WLED device; a WLED device was prepared by the existing method, and the obtained physical object is as Figure 6 shown in the insets of 6b, 6b(I) and 6b(II). Figure 6 6b(I) is a magnified photo of the physical object, and 6b(II) is a photo of the physical object in the lit state of the WLED device;

[0069] The HAAS-2000-VIS LED spectrometer was used to detect the optoelectronic performance of the WLED device, and the results are as Figure 6The spectrogram shown in b. From the obtained results, the spectral color coordinates of the device are (0.3399, 0.3730), indicating that the emission color of the fabricated device is in the standard white light region. In addition, the CCT is 5245 and the R a is 93, indicating that the preferred red phosphor can be combined with commercial phosphors to fabricate WLEDs with excellent performance.

[0070] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A near-zero thermal quenching high-efficiency red fluorescent silicate material, characterized in that: The chemical formula is Ba5Y 12(1-x) Zn[O(SiO4)]8:xEu 3+ , x=0.00~0.

50.

2. The near-zero thermal quenching high-efficiency red fluorescent silicate material according to claim 1, characterized in that: x＝0.25。 3. The near-zero thermal quenching high-efficiency red fluorescent silicate material according to claim 1, characterized in that: The chemical formula is Ba5Y 12(1-0.25) Zn[O(SiO4)]8:0.25Eu 3+ .

4. The near-zero thermal quenching high-efficiency red fluorescent silicate material according to claim 1, characterized in that: When the temperature changes from 25℃ to 200℃, the emission spectra at different temperatures are basically the same; At 150° C. and 200° C., the luminous integrated intensity of the sample obtained in Example 1 can maintain 97% and 95% of that at room temperature; the color coordinate values ​​are (0.6586, 0.3401).

5. A near-zero thermal quenching high-efficiency red fluorescent silicate material, characterized in that: The following steps are involved: The raw materials are mixed, ground, pre-sintered, heated, and subjected to solid phase reaction to obtain the near-zero thermal quenching high-efficiency red fluorescent silicate material as claimed in any one of claims 1 to 4.

6. The preparation method according to claim 5, characterized in that: The raw material is a Ba source, a Y source, a Zn source, a Si source, or a Li source; or the raw material is a Ba source, a Y source, a Zn source, a Si source, a Li source, or a Eu source; Preferably, the Ba source is BaCO3; the Y source is Y2O3; the Zn source is ZnO; the Si source is SiO2; the Li source is LiCO3; and the Eu source is Eu2O3.

7. The preparation method according to claim 5, characterized in that: The pre-sintering is carried out at 350-450°C for 20-30h, and the heating rate of the pre-sintering is 4-6°C / min; Preferably, after the pre-sintering, the sample is cooled to room temperature and then ground again for 25 to 35 minutes.

8. The preparation method according to claim 5, characterized in that: The solid phase reaction is to heat from room temperature to 1100-1200°C at a heating rate of 4-6°C / min, maintain at 1100-1200°C for 20-30h, and then cool to room temperature at a cooling rate of 4-6°C / min.

9. A red, green and blue tri-color phosphor composition excited by ultraviolet light, characterized in that: include: A highly efficient red fluorescent silicate material with near-zero thermal quenching according to any one of claims 1 to 4.

10. A WLED, characterized in that: include: The phosphor as claimed in claim 9.

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