Purple light excited cyan light emitting fluorescent material as well as preparation method and application thereof

Abstract

The invention relates to a purple light-excited cyan light-emitting fluorescent material as well as a preparation method and application thereof. The cyan light emitting fluorescent material is a Ce < 3 + > doped oxide cyan light emitting fluorescent material, the chemical expression of the cyan light emitting fluorescent material is SrCa0. 7Mg0. 3Lu4-xO8: xCe < 3 + >, and x is more than or equal to 0.003 and less than or equal to 0.05. The preparation method comprises the following steps: weighing a strontium source compound, a calcium source compound, a magnesium source compound, a lutetium source compound and a cerium source compound according to a stoichiometric ratio of a chemical expression of the green light emitting fluorescent material, grinding and uniformly mixing to obtain a mixture; sintering the mixture at high temperature, and cooling to obtain the purple light excited cyan fluorescent material. Compared with the prior art, the method has the advantages of optimizing the crystal field environment, constructing a cyan fluorescent material with wide-spectrum excitation characteristic, high luminous efficiency and excellent thermal stability and the like.

Description

Technical Field

[0001] This invention relates to the field of fluorescent materials technology, and in particular to a violet-excited cyan-emitting fluorescent material, its preparation method, and its application. Background Technology

[0002] In recent years, the rapid development of solid-state lighting technology has placed higher demands on the performance of fluorescent materials, especially in high-end lighting fields (such as full-spectrum LEDs and high color rendering index (CRI) health lighting), where there is an urgent need for high-efficiency fluorescent materials that can accurately fill the cyan wavelength range (450–500 nm). Traditional white LEDs mostly use blue chips to excite yellow phosphors, but the lack of the cyan region leads to insufficient color rendering index, making it difficult to achieve the continuity of the natural spectrum. Although some europium (Eu) and terbium (Tb) doped materials can emit cyan light, their excitation band is usually limited to the ultraviolet or near-ultraviolet region (<400 nm), resulting in low spectral matching with mainstream violet LED chips (400–420 nm). In addition, existing cyan fluorescent materials generally face bottlenecks such as poor thermal stability (significant decay of luminous intensity at high temperatures) and low internal quantum efficiency (usually below 40%), which seriously restricts their application in high-temperature operating environments and high-power lighting devices.

[0003] To address these issues, researchers began exploring novel rare-earth doping systems, in which cerium ions (Ce) are used. 3+ Ce2+, due to its 4f-5d transition characteristics, possesses advantages such as tunable excitation wavelength and short fluorescence lifetime, making it an important candidate for developing broadband excitation fluorescent materials. However, traditional Ce2+... 3+ Activation materials in oxide matrices are prone to emission peak shifting or broadening due to crystal field environment mismatch, making it difficult to achieve high-purity cyan light emission. Therefore, optimizing the crystal field environment through matrix composition design to construct cyan fluorescent materials with broad-spectrum excitation characteristics, high luminous efficiency, and excellent thermal stability has become a key technical challenge that urgently needs to be overcome in this field. This breakthrough will not only promote the efficient coupling of violet chips and fluorescent materials, but also provide core material support for the innovation of full-spectrum LED lighting, plant growth light sources, and display backlight technology.

[0004] Patent publication number CN119899668A discloses a cyan fluorescent material for violet-excited solar LEDs, its preparation method, and its application. The chemical formula of this fluorescent material is Ca2LuZr2Al. 1.5 Ga 1.5 O 12 :xCe 3+ Among them, 0.02≤x≤0.07, the excitation spectrum range covers 300~450nm, but there is still room for improvement in the thermal stability of this cyan fluorescent material. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art by providing a cyan-emitting fluorescent material excited by violet light, its preparation method and application, optimizing the crystal field environment, and constructing a cyan fluorescent material with broad-spectrum excitation characteristics, high luminescence efficiency and excellent thermal stability.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] One of the technical solutions of this invention is to provide a violet-excited cyan-emitting fluorescent material, wherein the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3 + Where 0.003≤x≤0.05.

[0008] Furthermore, x = 0.003, 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.04, 0.05.

[0009] Furthermore, the excitation spectrum of the cyan-emitting fluorescent material covers 280–450 nm.

[0010] Furthermore, the excitation wavelength of the cyan-emitting fluorescent material is 400–420 nm, with the optimal excitation wavelength being 410 nm.

[0011] Furthermore, the emission spectrum of the cyan-emitting fluorescent material covers the range of 420–650 nm, with a center wavelength at 475 nm.

[0012] Furthermore, under the excitation of the optimal excitation wavelength, the emission spectrum of the cyan-emitting fluorescent material covers the range of 420–650 nm, with a central wavelength at 475 nm.

[0013] Furthermore, the cyan-emitting fluorescent material is a powder.

[0014] The second technical solution of the present invention provides a method for preparing a cyan-emitting fluorescent material excited by violet light, comprising the following steps:

[0015] S1. Weigh out the strontium source compound, calcium source compound, magnesium source compound, lutetium source compound, and cerium source compound according to the stoichiometric ratio of the chemical expression of the blue light emitting fluorescent material, grind and mix them evenly to obtain a mixture;

[0016] S2. The mixture is sintered at high temperature and cooled to obtain the cyan fluorescent material excited by violet light.

[0017] Further, in step S1, the strontium source compound includes SrCO3;

[0018] The calcium source compound includes CaCO3;

[0019] The magnesium source compound includes (MgCO3)4·Mg(OH)2·5H2O;

[0020] The lutetium source compound includes Lu3O2;

[0021] The cerium source compound includes CeO2.

[0022] Furthermore, in step S1, the grinding time is 5 to 120 minutes.

[0023] Further, in step S2, the high-temperature sintering conditions are as follows: sintering at 900–1450°C for 4–15 hours in a reducing atmosphere selected from a mixture of 5% H2 and 95% N2 by volume.

[0024] Furthermore, the sintering temperature is 1100–1300℃, and the sintering time is 6–10 hours.

[0025] Furthermore, the reducing atmosphere refers to a mixture of 5% H2 and 95% N2 by volume.

[0026] Further, in step S2, the high-temperature sintering method is as follows: the mixture obtained in step S1 is placed in a crucible, and the crucible is placed in a vacuum tube furnace for high-temperature sintering under a reducing atmosphere.

[0027] The third technical solution of the present invention is to provide an application of a violet light-excited cyan light-emitting fluorescent material, which is used to prepare white LEDs, solar LEDs, and full-spectrum LEDs.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] (1) The cyan-emitting fluorescent material of the present invention is a novel, previously unreported cyan-emitting fluorescent material excited by violet light. The violet-excited cyan-emitting fluorescent material is an oxide-based phosphor with a wide excitation band. It can effectively absorb excitation light covering the range of 280 to 450 nm and can be excited by ultraviolet, violet, and blue light. It can be matched with various excitation chips for violet and ultraviolet light to achieve bright and dazzling cyan emission. The emission center is located at 475 nm and can be matched with commercial violet light chips.

[0030] (2) The fluorescent material of the present invention is a broad excitation blue light emission fluorescent material with the advantage of stable physicochemical properties. At the same time, the preparation process of the present invention is simple, does not require high temperature and high pressure, and is conducive to industrial production.

[0031] (3) The blue light emitting fluorescent material of the present invention has an emission wavelength of 420-650nm and can effectively absorb light in the wavelength range of 280-450nm. It can be well matched with existing violet light chips, has excellent light emission performance, meets the needs of commercial market, and has great development potential in the field of healthy lighting such as violet light-excited white light LED, violet light-excited solar-like LED, and violet light-excited full-spectrum LED.

[0032] (4) The SrCa of the present invention 0.7 Mg 0.3 Lu 4-x The O8 matrix, after synthesis, possesses the Pnma space group and belongs to the orthorhombic crystal system. The CeO2 used is reduced to Ce by hydrogen and nitrogen. 3+ It then reacts with the matrix to form a cyan phosphor.

[0033] (5) The SrCa of the present invention 0.7 Mg 0.3 Lu 4-x The O8 matrix uses LuO6 octahedrons as basic units, forming a three-dimensional rigid framework through shared vertex / edge connections. Its structure suppresses high-temperature lattice vibrations (reducing phonon energy) and reduces the conversion of excited state energy into thermal energy.

[0034] (6) In the blue-light emitting fluorescent material of the present invention, Mg 2+ -Lu 3+ Blocking vibrational energy to Ce 3+ Transmission, making Ce 3+ The surrounding phonon density decreases; Ca 2+ -Mg 2+ Stress balance prevents brittle fracture in the pure Mg system and reduces the coefficient of thermal expansion at high temperatures; Sr 2+ Stable Ce 3+ Lattice sites optimize crystal field splitting energy and enhance radiative transition rates; Ce 3+ It occupies a low-symmetry twisted octahedral site, with the 5d level deeply buried in a wide bandgap, resisting thermal ionization. Attached Figure Description

[0035] Figure 1 The images show the photoexcitation-emission spectra of the cyan-emitting fluorescent materials prepared in Examples 1-3 of this invention, where (a) is the excitation spectrum and (b) is the emission spectrum.

[0036] Figure 2 The graph shows the luminescence thermal stability of the cyan-emitting fluorescent material prepared in Example 2 of this invention. Detailed Implementation

[0037] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments. All other embodiments obtained by those skilled in the art based on the given embodiments without creative effort are within the scope of protection of this application.

[0038] Unless otherwise specified, the reagents, methods, instruments and equipment used in this invention are conventional reagents, methods, instruments and equipment in the art.

[0039] A violet-excited cyan-emitting fluorescent material, wherein the cyan-emitting fluorescent material is Ce 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where 0.003≤x≤0.05.

[0040] In some specific embodiments, x = 0.003, 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.04, 0.05.

[0041] In some specific embodiments, the excitation spectrum of the cyan-emitting fluorescent material covers 280–450 nm.

[0042] In some specific embodiments, the excitation wavelength of the cyan-emitting fluorescent material is 400–420 nm, with the optimal excitation wavelength being 410 nm.

[0043] In some specific embodiments, the cyan-emitting fluorescent material has an emission spectrum range of 420–650 nm, with a center wavelength of 475 nm.

[0044] In some specific embodiments, under the excitation of the optimal excitation wavelength, the emission spectrum of the cyan-emitting fluorescent material covers the range of 420–650 nm, with a center wavelength at 475 nm.

[0045] In some specific embodiments, the cyan-emitting fluorescent material is a powder.

[0046] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0047] S1. Weigh out the strontium source compound, calcium source compound, magnesium source compound, lutetium source compound, and cerium source compound according to the stoichiometric ratio of the chemical expression of the blue light emitting fluorescent material, grind and mix them evenly to obtain a mixture;

[0048] S2. The mixture is sintered at high temperature and cooled to obtain the cyan fluorescent material excited by violet light.

[0049] In some specific embodiments, in step S1, the strontium source compound includes SrCO3;

[0050] The calcium source compound includes CaCO3;

[0051] The magnesium source compound includes (MgCO3)4·Mg(OH)2·5H2O;

[0052] The lutetium source compound includes Lu3O2;

[0053] The cerium source compound includes CeO2.

[0054] In some specific embodiments, the grinding time in step S1 is 5 to 120 minutes.

[0055] In some specific embodiments, in step S2, the high-temperature sintering conditions are as follows: sintering at 900–1450°C for 4–15 hours in a reducing atmosphere selected from a mixture of 5% H2 and 95% N2 by volume.

[0056] In some specific embodiments, the sintering temperature is 1100–1300℃ and the sintering time is 6–10h.

[0057] In some specific embodiments, the reducing atmosphere refers to a mixture of 5% H2 and 95% N2 by volume.

[0058] In some specific embodiments, in step S2, the high-temperature sintering method is as follows: the mixture obtained in step S1 is placed in a crucible, and the crucible is placed in a vacuum tube furnace for high-temperature sintering under a reducing atmosphere.

[0059] An application of a violet-excited cyan-emitting fluorescent material, wherein the violet-excited cyan-emitting fluorescent material is used to prepare white LEDs, solar LEDs, and full-spectrum LEDs.

[0060] Each of the above embodiments can be implemented individually or in any combination of two or more.

[0061] The following description uses specific examples to illustrate the point.

[0062] Example 1

[0063] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0064] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1416:0.0672:0.0279:0.7628:0.0005, corresponding to x = 0.003. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g.

[0065] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1150°C for 8 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0066] In this embodiment, the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.003, i.e., the chemical formula is SrCa 0.7 Mg 0.3 Lu 3.997 O8:0.003Ce 3+ .

[0067] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000), such as... Figure 1 As shown in the figure. The results indicate that the phosphor in this system has a broad excitation band, covering the excitation spectrum from 280 to 450 nm, encompassing the ultraviolet and violet regions, with a peak at 410 nm, meaning the optimal excitation wavelength is 410 nm. This indicates that it can be effectively excited by ultraviolet and violet chips and matches well with various commercial chips. Under excitation by a 410 nm violet light source, the phosphor emits bright blue light, with an emission spectrum consisting of a broad emission band (420–650 nm) and a peak at 475 nm.

[0068] Example 2

[0069] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0070] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1416:0.0672:0.0279:0.7624:0.0008, corresponding to x = 0.005. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g.

[0071] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1200°C for 8.5 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0072] In this embodiment, the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.005, i.e., the chemical formula is SrCa 0.7 Mg 0.3 Lu 3.995 O8:0.005Ce 3+ .

[0073] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000), such as... Figure 1 As shown in the figure. The results indicate that the phosphor in this system has a broad excitation band, covering the excitation spectrum from 280 to 450 nm, encompassing the ultraviolet and violet regions, with a peak at 410 nm, meaning the optimal excitation wavelength is 410 nm. This indicates that it can be effectively excited by ultraviolet and violet chips and matches well with various commercial chips. Under excitation by a 410 nm violet light source, the phosphor emits bright blue light, with an emission spectrum consisting of a broad emission band (420–650 nm) and a peak at 475 nm.

[0074] Example 3

[0075] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0076] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1416:0.0672:0.028:0.7616:0.01, corresponding to x = 0.0017. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g.

[0077] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1300°C for 9 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0078] In this embodiment, the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.01, i.e., the chemical expression is SrCa 0.7 Mg 0.3 Lu 3.99 O8:0.01Ce 3 + .

[0079] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000), such as... Figure 1 As shown in the figure. The results indicate that the phosphor in this system has a broad excitation band, covering the excitation spectrum from 280 to 450 nm, encompassing the ultraviolet and violet regions, with a peak at 410 nm, meaning the optimal excitation wavelength is 410 nm. This indicates that it can be effectively excited by ultraviolet and violet chips and matches well with various commercial chips. Under excitation by a 410 nm violet light source, the phosphor emits bright blue light, with an emission spectrum consisting of a broad emission band (420–650 nm) and a peak at 475 nm.

[0080] Example 4

[0081] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0082] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1416:0.0672:0.028:0.7607:0.025, corresponding to x = 0.015. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g.

[0083] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1350°C for 10 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0084] In this embodiment, the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.015, i.e., the chemical formula is SrCa 0.7 Mg 0.3 Lu 3.985 O8:0.015Ce 3+ .

[0085] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000). The results showed that the fluorescence spectral properties of this cyan-emitting fluorescent material were similar to those in Example 1.

[0086] Example 5

[0087] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0088] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1417:0.0672:0.28:0.7599:0.0033, corresponding to x = 0.02. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g.

[0089] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1400°C for 11 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0090] In this embodiment, the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.02, the chemical formula is SrCa 0.7 Mg 0.3 Lu 3.98 O8:0.02Ce 3 + .

[0091] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000). The results showed that the fluorescence spectral properties of this cyan-emitting fluorescent material were similar to those in Example 1.

[0092] Example 6

[0093] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0094] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1417:0.0672:0.028:0.7581:0.005, corresponding to x = 0.03. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g.

[0095] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1450°C for 12 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0096] In this embodiment, the cyan-emitting fluorescent material is Ce.3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.03, i.e., the chemical formula is SrCa 0.7 Mg 0.3 Lu 3.97 O8:0.03Ce 3 + .

[0097] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000). The results showed that the fluorescence spectral properties of this cyan-emitting fluorescent material were similar to those in Example 1.

[0098] Example 7

[0099] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0100] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1417:0.0673:0.028:0.7564:0.0066, corresponding to x = 0.04. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g of the mixture.

[0101] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1450°C for 13 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0102] In this embodiment, the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.04, the chemical formula is SrCa 0.7 Mg 0.3 Lu 3.96 O8:0.04Ce 3+ .

[0103] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000). The results showed that the fluorescence spectral properties of this cyan-emitting fluorescent material were similar to those in Example 1.

[0104] Example 8

[0105] A method for preparing a cyan-emitting fluorescent material excited by violet light includes the following steps:

[0106] (1) SrCO3 (Titan, ≥99%), CaCO3 (Titan, ≥99%), (MgCO3)4·Mg(OH)2·5H2O (Titan, ≥98%), Lu2O3 (Titan, 99.99%), and CeO2 (Titan, 99.99%) were selected as starting materials. The ratio of Sr:Ca:Mg:Lu:Ce was 0.1418:0.0673:0.028:0.7547:0.0083, corresponding to x = 0.05. The five raw materials were weighed separately, and the total mass of the raw material mixture was controlled to be 10g.

[0107] (2) The above mixture was ground in an agate mortar for 30 minutes. After the mixture was evenly mixed, it was loaded into an alumina crucible. The alumina crucible containing the raw material was then placed in a reducing atmosphere of hydrogen and nitrogen (a mixture of 5% H2 and 95% N2 by volume) and calcined at 1450°C for 11.5 hours. After that, it was cooled to room temperature to obtain the powdered target product.

[0108] In this embodiment, the cyan-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where x = 0.05, i.e., the chemical formula is SrCa 0.7 Mg 0.3 Lu 3.95 O8:0.05Ce 3 + .

[0109] (3) The spectral properties of the phosphor in this system were tested using a fluorescence spectrometer (HITACHI F-7000). The results showed that the fluorescence spectral properties of this cyan-emitting fluorescent material were similar to those in Example 1.

[0110] Comparative Example 1

[0111] This comparative example provides a violet-excited cyan phosphor, the specific preparation method of which is as follows:

[0112] (1) CaCO3, (MgCO3)4·Mg(OH)2·5H2O, Lu2O3, and CeO2 were selected as starting materials, with a mass ratio of CaCO3, (MgCO3)4·Mg(OH)2·5H2O, Lu2O3, and CeO2 = 0.1709:0.0293:0.7989:0.009. The five materials were weighed separately, and the total mass of the mixture was controlled to be 10g.

[0113] (2) The above raw material mixture was placed in an agate mortar and ground for 60 minutes. After the material was mixed evenly, the mixture was loaded into an alumina crucible and calcined at 1200°C for 8.5 hours in a hydrogen-nitrogen mixed atmosphere. Then it was cooled to room temperature to obtain the target product.

[0114] This embodiment yields a cyan phosphor excited by violet light, with the general formula Ca. 1.7 Mg 0.3 Lu 4-x O8:xCe 3+ , where x = 0.005.

[0115] Comparative Example 2

[0116] This comparative example provides a violet-excited cyan phosphor, the specific preparation method of which is as follows:

[0117] (1) SrCO3, (MgCO3)4·Mg(OH)2·5H2O, Lu2O3, and CeO2 were selected as starting materials, with a mass ratio of SrCO3, (MgCO3)4·Mg(OH)2·5H2O, Lu2O3, and CeO2 = 0.1033:0.3399:0.5562:0.006. The five materials were weighed separately, and the total mass of the mixture was controlled to be 10g.

[0118] (2) The above raw material mixture was placed in an agate mortar and ground for 60 minutes. After the material was mixed evenly, the mixture was loaded into an alumina crucible and calcined at 1200°C for 8.5 hours in a hydrogen-nitrogen mixed atmosphere. Then it was cooled to room temperature to obtain the target product.

[0119] This embodiment yields a cyan phosphor excited by violet light, with the general formula SrMgLu. 4-x O8:xCe 3+ , where x = 0.005.

[0120] Comparative Example 3

[0121] This comparative example provides a violet-excited cyan phosphor, the specific preparation method of which is as follows:

[0122] (1) Weigh SrCO3, CaCO3, Lu2O3 and CeO2 as starting materials according to the stoichiometric ratio. The mass ratio of each material is SrCO3, CaCO3, Lu2O3 and CeO2 = 0.1415:0.0959:0.7618:0.008.

[0123] (2) The above raw material mixture was placed in an agate mortar and ground for 60 minutes. After the material was mixed evenly, the mixture was loaded into an alumina crucible and calcined at 1200°C for 8.5 hours in a hydrogen-nitrogen mixed atmosphere. Then it was cooled to room temperature to obtain the target product.

[0124] The violet-excited cyan phosphor obtained in this embodiment has the general formula SrCaLu. 4-x O8:xCe 3+ , where x = 0.005.

[0125] The reaction conditions and related properties of the cyan-emitting fluorescent materials in Examples 1-8 are shown in Table 1.

[0126] Table 1. Summary of preparation parameters and test results of cyan-emitting fluorescent materials in Examples 1-3

[0127] composition Example 1 Example 2 Example 3 <![CDATA[SrCO3]]> 0.1416 0.1416 0.1416 <![CDATA[CaCO3]]> 0.0672 0.0672 0.0672 <![CDATA[(MgCO3)4·Mg(OH)2·5H2O]]> 0.0279 0.0279 0.028 <![CDATA[Lu2O3]]> 0.7628 0.7624 0.7616 <![CDATA[CeO2]]> 0.0005 0.0008 0.01 Restoration time (h) 8 8.5 9 Reduction temperature (°C) 1150℃ 1200℃ 1300℃ Sintering Atmosphere <![CDATA[5%H2 / 95%N2]]> <![CDATA[5%H2 / 95%N2]]> <![CDATA[5%H2 / 95%N2]]> Excitation wavelength (nm) 410 410 410 Emission wavelength (nm) 475 475 475

[0128] Figure 2 SrCa in Example 2 0.7 Mg 0.3 Lu 3.995 O8:0.005Ce 3+ The thermal stability graph was measured every 30°C, and the thermal stability at 120°C was 80.83% of that at room temperature.

[0129] This is because Sr, Ca, Mg, Lu, and O together form the lattice structure, providing stable physical support and a specific chemical environment for the luminescent centers. Ce 3+ As an activating ion doped into the matrix, it becomes the luminescent center that actually generates light emission. The SrCa of this invention... 0.7 Mg 0.3 Lu 4-x The O8 matrix, after synthesis, possesses the Pnma space group and belongs to the orthorhombic crystal system. The CeO2 used is reduced to Ce by hydrogen and nitrogen. 3+ It then reacts with the matrix to form a cyan phosphor.

[0130] In the cyan-emitting fluorescent material of the present invention, Mg 2+ -Lu 3+ Blocking vibrational energy to Ce 3+ Transmission, making Ce 3+ The surrounding phonon density decreases; Ca 2+ -Mg 2+Stress balance prevents brittle fracture in the pure Mg system and reduces the coefficient of thermal expansion at high temperatures; Sr 2+ Stable Ce 3+ Lattice sites optimize crystal field splitting energy and enhance radiative transition rates; Ce 3+ Occupying a low-symmetry twisted octahedral lattice site, the 5d level is deeply buried in a wide wide gap, resisting thermal ionization. SrCa 0.7 Mg 0.3 Lu 4-x The O8 matrix uses LuO6 octahedrons as basic units, forming a three-dimensional rigid framework through shared vertex / edge connections. This structure suppresses high-temperature lattice vibrations (reducing phonon energy) and minimizes the conversion of excited-state energy into thermal energy. The unique Lu4O8 structure and the resulting Ce... 3+ The octahedral coordination environment has a relatively small crystal field splitting energy.

[0131] Although the present invention has been described in detail above with general descriptions, specific embodiments, and experiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A cyan-emitting fluorescent material excited by violet light, characterized in that, The blue-emitting fluorescent material is Ce. 3+ Doped oxide blue-emitting fluorescent materials, with the chemical formula SrCa 0.7 Mg 0.3 Lu 4-x O8:xCe 3+ Where 0.003≤x≤0.

05.

2. The violet-excited cyan-emitting fluorescent material according to claim 1, characterized in that, x＝0.003、0.005、0.01、0.015、0.02、0.025、0.03、0.04、0.05。 3. The violet-excited cyan-emitting fluorescent material according to claim 1, characterized in that, The excitation spectrum of the cyan-emitting fluorescent material covers 280–450 nm.

4. The violet-excited cyan-emitting fluorescent material according to claim 3, characterized in that, The excitation wavelength of the cyan-emitting fluorescent material is 400–420 nm.

5. The violet-excited cyan-emitting fluorescent material according to claim 1, characterized in that, The emission spectrum of the cyan-emitting fluorescent material covers the range of 420–650 nm, with a center wavelength of 475 nm.

6. The violet-excited cyan-emitting fluorescent material according to claim 1, characterized in that, The cyan-emitting fluorescent material is a powder.

7. A method for preparing a violet-excited cyan-emitting fluorescent material as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Weigh out the strontium source compound, calcium source compound, magnesium source compound, lutetium source compound, and cerium source compound according to the stoichiometric ratio of the chemical expression of the blue light emitting fluorescent material, grind and mix them evenly to obtain a mixture; S2. The mixture is sintered at high temperature and cooled to obtain the cyan fluorescent material excited by violet light.

8. The method for preparing a violet-excited cyan-emitting fluorescent material according to claim 1, characterized in that, In step S1, the strontium source compound includes SrCO3; The calcium source compound includes CaCO3; The magnesium source compound includes (MgCO3)4·Mg(OH)2·5H2O; The lutetium source compound includes Lu3O2; The cerium source compound includes CeO2.

9. The method for preparing a violet-excited cyan-emitting fluorescent material according to claim 1, characterized in that, In step S2, the conditions for high-temperature sintering are: vacuuming, maintaining a reducing atmosphere, and sintering at 900–1450°C for 4–15 hours.

10. The application of a violet-excited cyan-emitting fluorescent material as described in any one of claims 1 to 6, characterized in that, The cyan-emitting fluorescent material excited by violet light is used to prepare white LEDs, solar LEDs, and full-spectrum LEDs.

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