A Eu 2+ -doped single-phase white light-emitting phosphor and preparation method thereof

Abstract

The present invention discloses a Eu 2+ -doped single-phase white light-emitting phosphor and a preparation method thereof. The Eu 2+ -doped single-phase white light-emitting phosphor of the present invention has a chemical general formula of Ca 9‑y LiMg 1‑x A 2x / 3 (PO4)7: yEu 2+ , wherein A is selected from Al and / or Ga; x and y respectively represent numerical values within the following ranges: 0.1 ≤ x < 1.0, 0.001 ≤ y ≤ 0.2. The Eu 2+ -doped single-phase white light-emitting phosphor of the present invention, by adding Al and / or Ga, causes local structural distortion, induces the redistribution of Eu 2+ , thereby broadening the full width at half maximum of the emission peak and the emission band, enabling its spectral range to cover the entire visible light region, having good continuity of the emission spectrum and a complete spectrum, and the peak shape of its emission peak being similar to the visible light peak shape of sunlight, improving the luminescence quality of the phosphor, making its emitted light close to the natural light level, and having a good LED white light illumination effect.

Description

Technical Field

[0001] The present invention relates to the technical field of inorganic luminescent materials, and more specifically, to a Eu 2+ -doped single-phase white light-emitting phosphor and a preparation method thereof. Background Art

[0002] Single-phase white light-emitting phosphors are potential luminescent materials for white LED devices. Currently, single-phase white light-emitting phosphors are usually developed by co-doping with multiple activator ions. However, co-doping with multiple activator ions often faces energy transfer between different activator ions, and energy loss occurs during the energy transfer process, resulting in low luminescence efficiency of the single white light-emitting phosphor developed by this method. The white light-emitting phosphor developed by doping with a single activator ion (such as Eu 2+ ) can effectively overcome the above problems and is an effective way to develop more efficient white light-emitting phosphors.

[0003] However, compared with the solar spectrum, the white light-emitting phosphors developed by doping with a single activator ion usually have problems of poor emission spectrum continuity and partial spectrum absence, which affect the luminescence quality of the phosphors, make the emitted light far from the natural light level, and are not conducive to healthy lighting. For example, the LiCa3MgV3O 12 :Eu 3+ phosphor prepared by the high-temperature solid-phase reaction method in the article (Yan Xiaosong, Li Wanwan, Liu Ji, etc. A single-phase white light-emitting phosphor suitable for near-ultraviolet LED excitation [J]. Chinese Journal of Luminescence, 2010, 31(1): 39-43.) has problems of poor emission spectrum continuity and partial spectrum absence.

[0004] Therefore, it is of great significance to develop a Eu 2+ -doped single-phase white light-emitting phosphor with good emission spectrum continuity and complete spectrum similar to sunlight emission. Summary of the Invention

[0005] The primary object of the present invention is to overcome the problems of poor emission spectrum continuity and partial spectrum absence in the single-phase white light-emitting phosphor in the above-mentioned prior art, and to provide a Eu 2+ -doped single-phase white light-emitting phosphor.

[0006] Another object of the present invention is to provide a preparation method of a Eu 2+ -doped single-phase white light-emitting phosphor.

[0007] Still another object of the present invention is to provide an application of a Eu 2+ -doped single-phase white light-emitting phosphor in the preparation of LED devices.

[0008] The above technical object of the present invention is achieved by the following technical solutions:

[0009] A kind of Eu 2+ -doped single-phase white light-emitting phosphor, whose chemical general formula is Ca 9-y LiMg 1-x A 2x / 3 (PO4)7: yEu 2 + , wherein, A is selected from Al and / or Ga; x and y respectively represent the numerical values in the following ranges: 0.1 ≤ x < 1.0, 0.001 ≤ y ≤ 0.2.

[0010] The Eu 2+ -doped single-phase white light-emitting phosphor of the present invention uses Eu 2+ as a single activating ion, uses Ca9LiMg(PO4)7 as a matrix structure, and by adding Al 3+ and / or Ga 3+ , causes local structural distortion, induces the redistribution of Eu 2+ , thereby broadening the full width at half maximum of the emission peak and the emission wavelength band, enabling its spectral range to cover the entire visible light region, having good continuity of the emission spectrum and a complete spectrum, and the peak shape of its emission peak being similar to the visible light peak shape of sunlight, improving the luminescence quality of the phosphor, making its emitted light close to the natural light level, and having a good LED white light illumination effect.

[0011] The reason why A in the present invention can be selected from Al and / or Ga is that Al and Ga are not only in the same main group, but also have similar atomic radii and can replace each other.

[0012] Specifically, the A is Al.

[0013] Specifically, the x represents the numerical value in the following range: 0.1 ≤ x ≤ 0.9.

[0014] Further, the x represents the numerical value in the following range: 0.25 ≤ x ≤ 0.75.

[0015] Specifically, the y represents the numerical value in the following range: 0.01 ≤ y ≤ 0.1.

[0016] Further, the y represents the numerical value in the following range: y = 0.01.

[0017] A preparation method of a Eu 2+ -doped single-phase white light-emitting phosphor includes the following steps:

[0018] Mix a calcium source, a lithium source, a magnesium source, an A source, a phosphorus source, and a europium source, and perform sintering treatment in a reducing atmosphere to obtain the Eu 2+ -doped single-phase white light-emitting phosphor;

[0019] The A source is selected from an aluminum source and / or a gallium source.

[0020] Specifically, the aluminum source is selected from one or two of aluminum oxides or hydroxides.

[0021] Further, the aluminum source is selected from aluminum oxides, specifically aluminum oxide (Al2O3).

[0022] Specifically, the gallium source is selected from one or two of gallium oxides or hydroxides.

[0023] Further, the gallium source is selected from gallium oxides, specifically gallium oxide (Ga2O3).

[0024] Specifically, the calcium source is selected from one or more of calcium carbonate, bicarbonate, oxalate, nitrate, sulfate, oxide, nitride, fluoride, chloride or bromide.

[0025] Further, the calcium source is selected from calcium carbonate, specifically calcium carbonate.

[0026] Specifically, the lithium source is selected from one or more of lithium carbonate, bicarbonate, oxalate, nitrate, sulfate, oxide, nitride, fluoride, chloride or bromide.

[0027] Further, the lithium source is selected from lithium carbonate, specifically lithium carbonate.

[0028] Specifically, the magnesium source is selected from one or more of magnesium carbonate, bicarbonate, oxalate, nitrate, sulfate, oxide, nitride, fluoride, chloride or bromide.

[0029] Further, the magnesium source is selected from magnesium oxide, specifically magnesium oxide (MgO).

[0030] Specifically, the europium source is selected from one or more of europium carbonate, bicarbonate, oxalate, nitrate, sulfate, oxide, nitride, fluoride, chloride or bromide.

[0031] Further, the europium source is selected from europium oxides, specifically europium oxide (Eu2O3).

[0032] Specifically, the phosphorus source is selected from one or more of phosphates, dihydrogen phosphates or hydrogen phosphates.

[0033] Further, the phosphorus source is selected from one of dihydrogen phosphates or hydrogen phosphates.

[0034] Furthermore, the phosphorus source is selected from ammonium dihydrogen phosphate or diammonium hydrogen phosphate.

[0035] Specifically, the reducing atmosphere is selected from a CO atmosphere, an H2 atmosphere, a nitrogen-hydrogen mixed atmosphere or an argon-hydrogen mixed atmosphere.

[0036] Specifically, the temperature of the sintering treatment is 1150-1400 °C, and the heating rate is 1-10 °C / min.

[0037] Further, the temperature of the sintering treatment is 1250 °C, and the heating rate is 5 °C / min.

[0038] Specifically, the time of the sintering treatment is 1-12 h.

[0039] The above Eu 2+ The application of the doped single-phase white light-emitting phosphor in the preparation of LED devices should also be within the protection scope of the present invention.

[0040] The present invention has the following beneficial effects:

[0041] The Eu 2+ doped single-phase white light-emitting phosphor of the present invention uses Eu 2+ as a single activator ion, uses Ca9LiMg(PO4)7 as a matrix structure, and by adding Al and / or Ga, causes local structural distortion, induces the redistribution of Eu 2+ , thereby broadening the full width at half maximum of the emission peak and the emission band, so that its spectral range covers the entire visible light region, the emission spectrum has good continuity and integrity, and the peak shape of its emission peak is similar to the visible light peak shape of sunlight, improving the luminescence quality of the phosphor, making its emitted light close to the natural light level, and having a good LED white light illumination effect.

[0042] In addition, the Eu 2+ doped single-phase white light-emitting phosphor of the present invention has good color stability under high temperature conditions. Moreover, the preparation method of the Eu 2+ doped single-phase white light-emitting phosphor adopted by the present invention has the characteristics of simple process, controllable conditions and low preparation cost.

[0043] Therefore, the Eu 2+ doped single-phase white light-emitting phosphor of the present invention can be used in fields such as healthy and comfortable full-spectrum lighting, visible light communication, and smart agriculture. Description of the Drawings

[0044] Figure 1 For the X-ray powder diffraction pattern of the Eu 2+ doped single-phase white light-emitting phosphor in Example 1.

[0045] Figure 2 For the emission spectrum diagram of the Eu 2+ doped single-phase white light-emitting phosphor in Example 1.

[0046] Figure 3 For Comparative Example 1 Eu 2+ Emission spectrum diagram of the doped phosphor.

[0047] Figure 4 For Example 2 Eu 2+ Emission spectrum diagram of the doped single-phase white light-emitting phosphor.

[0048] Figure 5 For Example 3 Eu 2+ Emission spectrum diagram of the doped single-phase white light-emitting phosphor.

[0049] Figure 6 For Example 1 Eu 2+ Color stability diagram of the doped single-phase white light-emitting phosphor. Detailed implementation mode

[0050] The present invention will be further described below in conjunction with embodiments. These embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. The experimental methods without specific conditions in the following examples are usually carried out according to the conventional conditions in the art or according to the conditions recommended by the manufacturer; the raw materials, reagents, etc. used, unless otherwise specified, are all raw materials and reagents that can be obtained from commercial channels such as conventional markets. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention fall within the scope of protection required by the present invention.

[0051] Example 1

[0052] This example provides a Eu 2+ doped single-phase white light-emitting phosphor, whose chemical formula is Ca 8.99 LiMg 1 / 2 Al 1 / 3 (PO4)7:0.01Eu 2+ ; its preparation method includes the following steps:

[0053] Mix and grind 1.0105 g of calcium carbonate (CaCO3), 0.0415 g of lithium carbonate (Li2CO3), 0.0226 g of magnesium oxide (MgO), 0.0191 g of aluminum oxide (Al2O3), 0.9043 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0020 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer it to a corundum crucible and place it in an atmosphere sintering furnace. Introduce a reducing atmosphere of nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat it to 1250 °C at a heating rate of 5 °C / min, carry out sintering treatment, keep the temperature at 1250 °C for 5 h during sintering, and naturally cool it to room temperature. Further grind the sintered product to obtain the chemical formula Ca 8.99 LiMg 1 / 2Al1 / 3 (PO4)7:0.01Eu 2+ Eu-doped single-phase white light-emitting phosphor. 2+ Doped single-phase white light-emitting phosphor.

[0054] Examples 2 to 3 and Comparative Example 1

[0055] Examples 2 to 3 provide different Eu 2+ Doped single-phase white light-emitting phosphor and its preparation method, and Comparative Example 1 provides Eu 2+ Doped phosphor, the difference between them and Example 1 is that the dosages of the magnesium source and the A source are different. At the same time, Examples 2 to 3 and Comparative Example 1 also have different chemical formulas from Example 1, as shown in the following table. The rest are the same as Example 1:

[0056] Table 1 Phosphor Formulas of Examples 1 to 3 and Comparative Example 1

[0057]

[0058]

[0059] Example 4

[0060] This example provides a Eu 2+ Doped single-phase white light-emitting phosphor with the chemical formula Ca 8.999 LiMg 9 / 10 Al 1 / 15 / (PO4)7:0.001Eu 2+ ; Its preparation method includes the following steps:

[0061] Mix and grind 1.0105 g of calcium carbonate (CaCO3), 0.0414 g of lithium carbonate (Li2CO3), 0.0407 g of magnesium oxide (MgO), 0.0038 g of aluminum oxide (Al2O3), 0.9034 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0002 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place it in an atmosphere sintering furnace. Introduce a reducing atmosphere of nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat it to 1250 °C at a heating rate of 5 °C / min, perform sintering treatment, keep the temperature at 1250 °C for 5 h for sintering, and cool it naturally to room temperature. Further grind the sintered product to obtain the Eu with the chemical formula Ca 8.999 LiMg 9 / 10 Al 1 / 15 / (PO4)7:0.001Eu 2+ Doped single-phase white light-emitting phosphor. 2+ Doped single-phase white light-emitting phosphor.

[0062] Example 5

[0063] This example provides a Eu 2+ doped single-phase white light-emitting phosphor with the chemical formula Ca 8.8 LiMg 1 / 10 Al 3 / 5 (PO4)7:0.2Eu 2+ ; The preparation method includes the following steps:

[0064] Mix and grind 0.9826 g of calcium carbonate (CaCO3), 0.0412 g of lithium carbonate (Li2CO3), 0.0045 g of magnesium oxide (MgO), 0.0341 g of aluminum oxide (Al2O3), 0.8983 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0393 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place it in an atmosphere sintering furnace. Pass a reducing atmosphere nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat it to 1250 °C at a heating rate of 5 °C / min, carry out sintering treatment, keep the temperature at 1250 °C for 5 h for sintering, and naturally cool to room temperature. Further grind the sintered product to obtain the Eu 8.8 LiMg 1 / 10 Al 3 / 5 (PO4)7:0.2Eu 2+ doped single-phase white light-emitting phosphor. 2+

[0065] Example 6

[0066] This example provides a Eu 2+ doped single-phase white light-emitting phosphor with the chemical formula Ca 8.99 LiMg 1 / 2 Ga 1 / 3 (PO4)7:0.01Eu 2+ ; The preparation method includes the following steps:

[0067] ​Mix and grind 1.0025 g of calcium carbonate (CaCO3), 0.0412 g of lithium carbonate (Li2CO3), 0.0225 g of magnesium oxide (MgO), 0.0348 g of gallium oxide (Ga2O3), 0.8971 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0020 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place in an atmosphere sintering furnace. Pass a reducing atmosphere nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat to 1250 °C at a heating rate of 5 °C / min for sintering treatment, keep the temperature at 1250 °C for 5 h for sintering, and cool naturally to room temperature. Further grind the sintered product to obtain a Eu 8.99 LiMg 1 / 2Ga 1 / 3 (PO4)7:0.01Eu 2+ doped single-phase white light-emitting phosphor. 2+

[0068] Example 7

[0069] This example provides a Eu 2+ doped single-phase white light-emitting phosphor with the chemical formula Ca 8.99 LiMg 3 / 4 Ga 1 / 6 (PO4)7:0.01Eu 2+ ; its preparation method includes the following steps:

[0070] Mix and grind 1.0056 g of calcium carbonate (CaCO3), 0.0413 g of lithium carbonate (Li2CO3), 0.0338 g of magnesium oxide (MgO), 0.0175 g of gallium oxide (Ga2O3), 0.8999 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0020 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place in an atmosphere sintering furnace. Pass a reducing atmosphere nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat to 1250 °C at a heating rate of 5 °C / min for sintering treatment, keep the temperature at 1250 °C for 5 h for sintering, and cool naturally to room temperature. Further grind the sintered product to obtain a Eu 8.99 LiMg 3 / 4Ga 1 / 6 (PO4)7:0.01Eu 2+ doped single-phase white light-emitting phosphor. 2+

[0071] Example 8

[0072] This example provides a Eu 2+Doped single-phase white light-emitting phosphor with the chemical formula Ca 8.99 LiMg 1 / 4 Ga 1 / 2 (PO4)7:0.01Eu 2+ ; The preparation method includes the following steps:

[0073] Mix and grind 0.9994 g of calcium carbonate (CaCO3), 0.0410 g of lithium carbonate (Li2CO3), 0.0112 g of magnesium oxide (MgO), 0.0520 g of gallium oxide (Ga2O3), 0.8944 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0020 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place it in an atmosphere sintering furnace. Pass a reducing atmosphere nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat it to 1250 °C at a heating rate of 5 °C / min for sintering treatment, keep the sintering temperature at 1250 °C for 5 h, cool it naturally to room temperature, and further grind the sintered product to obtain the phosphor with the chemical formula Ca 8.99 LiMg 1 / 4Ga 1 / 2 (PO4)7:0.01Eu 2+ -doped single-phase white light-emitting phosphor. 2+

[0074] Example 9

[0075] This example provides a Eu 2+ -doped single-phase white light-emitting phosphor with the chemical formula Ca 8.99 LiMg 1 / 2 Al 1 / 6Ga 1 / 6 (PO4)7:0.01Eu(PO4)7:0.01Eu 2+ ; The preparation method includes the following steps:

[0076] Mix and grind 1.0065 g of calcium carbonate (CaCO3), 0.0413 g of lithium carbonate (Li2CO3), 0.0225 g of magnesium oxide (MgO), 0.0095 g of aluminum oxide (Al2O3), 0.0175 g of gallium oxide (Ga2O3), 0.9007 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0020 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place it in an atmosphere sintering furnace. Pass a reducing atmosphere nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat it to 1250 °C at a heating rate of 5 °C / min for sintering treatment, keep the sintering temperature at 1250 °C for 5 h, cool it naturally to room temperature, and further grind the sintered product to obtain the phosphor with the chemical formula Ca 8.99 LiMg 1 / 2Al 1 / 6 Ga 1 / 6 (PO4)7:0.01Eu 2+ doped single-phase white light-emitting phosphor. 2+ Doped single-phase white light-emitting phosphor.

[0077] Example 10

[0078] This example provides a Eu 2+ doped single-phase white light-emitting phosphor with the chemical formula Ca 8.95 LiMg 1 / 2 Al 1 / 3 (PO4)7:0.05Eu 2+ ; Its preparation method includes the following steps:

[0079] Mix and grind 1.0043 g of calcium carbonate (CaCO3), 0.0414 g of lithium carbonate (Li2CO3), 0.0226 g of magnesium oxide (MgO), 0.0191 g of aluminum oxide (Al2O3), 0.9028 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0099 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place it in an atmosphere sintering furnace. Pass a reducing atmosphere nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat it to 1250 °C at a heating rate of 5 °C / min, carry out sintering treatment, keep the temperature at 1250 °C for 5 h for sintering, and naturally cool to room temperature. Further grind the sintered product to obtain the Eu 8.95 LiMg 1 / 2Al 1 / 3 (PO4)7:0.05Eu 2+ doped single-phase white light-emitting phosphor. 2+ Doped single-phase white light-emitting phosphor.

[0080] Example 11

[0081] This example provides a Eu 2+ doped single-phase white light-emitting phosphor with the chemical formula Ca 8.95 LiMg 1 / 2 Al 1 / 3 (PO4)7:0.05Eu 2+ ; Its preparation method includes the following steps:

[0082] Mix and grind 0.9966 g of calcium carbonate (CaCO3), 0.0413 g of lithium carbonate (Li2CO3), 0.0225 g of magnesium oxide (MgO), 0.0190 g of aluminum oxide (Al2O3), 0.9008 g of ammonium dihydrogen phosphate (NH4H2PO4) and 0.0197 g of europium oxide (Eu2O3) in an agate mortar for 30 min, then transfer to a corundum crucible and place in an atmosphere sintering furnace. Pass a reducing atmosphere nitrogen-hydrogen mixture (92% N2, 8% H2) into the furnace body, heat to 1250 °C at a heating rate of 5 °C / min for sintering treatment, hold for 5 h at 1250 °C, cool naturally to room temperature, and further grind the sintered product to obtain a Eu 8.95 LiMg 1 / 2Al 1 / 3 (PO4)7:0.05Eu 2+ -doped single-phase white light-emitting phosphor. 2+

[0083] Sample Characterization

[0084] Perform X-ray powder diffraction analysis and emission spectrum analysis on the Eu 2+ -doped single-phase white light-emitting phosphor of each embodiment of the present invention and the Eu 2+ -doped phosphor of Comparative Example 1.

[0085] Figure 1 The X-ray powder diffraction pattern of the Eu 2+ -doped single-phase white light-emitting phosphor of Example 1. It can be seen from Figure 1 that the Eu 2+ -doped single-phase white light-emitting phosphor of the present invention was successfully prepared.

[0086] Figure 2 The emission spectrum diagram of the Eu 2+ -doped single-phase white light-emitting phosphor of Example 1. Figure 3 The emission spectrum diagram of the Eu 2+ -doped phosphor of Comparative Example 1. It can be seen from Figures 2 - 3 that the emission wavelength range of the Eu 2+ -doped single-phase white light-emitting phosphor of the present invention is 375 - 830 nm, and the full width at half maximum of the emission peak reaches about 330 nm, indicating that the Eu 2+ -doped single-phase white light-emitting phosphor of the present invention uses Eu 2+ as a single activator ion, uses Ca9LiMg(PO4)7 as the matrix structure, and by adding Al, local structural distortion is caused, inducing Eu 2+The redistribution broadens the full width at half maximum of the emission peak and the emission band, enabling its emission spectrum to cover the entire visible light region. The emission spectrum has good continuity and integrity, and the shape of its emission peak is similar to that of the visible light peak of sunlight, improving the luminescence quality of the phosphor, making its emitted light approach the natural light level, and having a good LED white light illumination effect.

[0087] Figure 4 For Example 2 Eu 2+ Emission spectrum diagram of a single-phase white light-emitting phosphor doped with Eu. Figure 5 For Example 3 Eu 2+ Emission spectrum diagram of a single-phase white light-emitting phosphor doped with Eu. From Figures 4 - 5 It can be seen that the more the content of aluminum in the single-phase white light-emitting phosphor doped with Eu 2+ the more similar the shape of the emission peak is to that of the visible light peak of sunlight, and the emission spectrum has good continuity and integrity.

[0088] In addition, the emission spectrum diagrams of Example 4, 7 and the single-phase white light-emitting phosphor doped with Eu 2+ are similar, and the emission spectrum diagrams of Example 5, 8 and the single-phase white light-emitting phosphor doped with Eu 2+ are similar, and the emission spectrum diagrams of Example 6, 9 - 11 and the single-phase white light-emitting phosphor doped with Eu 2+ are similar.

[0089] Performance Test

[0090] The single-phase white light-emitting phosphor doped with Eu in each embodiment of the present invention 2+ was subjected to a test on the photochromic stability: The single-phase white light-emitting phosphor doped with Eu 2 + was placed in an Oxford temperature control device, and the emission spectrum at room temperature (300K) and 425K was measured using an Edinburgh fluorescence spectrometer, and the CIE chromaticity coordinates at each temperature were obtained through conversion.

[0091] Figure 6 For Example 1 Eu 2+ Photochromic stability diagram of a single-phase white light-emitting phosphor doped with Eu. From Figure 6 it can be seen that the CIE chromaticity coordinates of the single-phase white light-emitting phosphor doped with Eu 2+ in Example 1 at 300K and 425K are almost overlapping, with only a slight shift, indicating that the single-phase white light-emitting phosphor doped with Eu 2+ can maintain a stable photochromic output at different working temperatures, that is, the single-phase white light-emitting phosphor doped with Eu 2+ in the present invention has good photochromic stability under high temperature conditions.

[0092] The Eu in Embodiments 2 to 11 of the present invention 2+ The doped single-phase white light-emitting phosphor has similar light color stability to that of Example 1.

[0093] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. 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 claims of the present invention.

Claims

1. A Eu 2+ -doped single-phase white light-emitting phosphor, characterized in that Its chemical general formula is Ca 9-y LiMg 1-x A 2x / 3 (PO4)7: yEu 2+ , where A is Al; x and y respectively represent numerical values in the following ranges: 0.1 ≤ x < 1.0, 0.001 ≤ y ≤ 0.

2.

2. The Eu 2+ -doped single-phase white light-emitting phosphor according to claim 1, characterized in that The x represents a numerical value in the following range: 0.1 ≤ x ≤ 0.

9.

3. The Eu 2+ -doped single-phase white light-emitting phosphor according to claim 1, characterized in that The y represents a numerical value in the following range: 0.01 ≤ y ≤ 0.

1.

4. The preparation method of the Eu 2+ -doped single-phase white light-emitting phosphor according to any one of claims 1 to 3, characterized in that It includes the following steps: Mix a calcium source, a lithium source, a magnesium source, an A source, a phosphorus source, and a europium source, and perform sintering treatment under a reducing atmosphere to obtain Eu 2+ -doped single-phase white light-emitting phosphor; The A source is selected from aluminum sources.

5. The preparation method of the Eu 2+ -doped single-phase white light-emitting phosphor according to claim 4, characterized in that The aluminum source is selected from one or two of aluminum oxides or hydroxides.

6. The preparation method of the Eu 2+ -doped single-phase white light-emitting phosphor according to claim 4, characterized in that The europium source is selected from one or more of europium carbonate, bicarbonate, oxalate, nitrate or oxide.

7. The preparation method of the Eu 2+ -doped single-phase white light-emitting phosphor according to claim 4, characterized in that The calcium source is selected from one or more of calcium carbonate, bicarbonate, oxalate, nitrate or oxide.

8. The application of the Eu 2+ -doped single-phase white light-emitting phosphor according to any one of claims 1 to 3 in the preparation of LED devices.

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