Eu-doped fluorescent glass-ceramics, preparation method thereof, and fluorescence performance control method

Abstract

The present invention provides a Eu-doped fluorescent microcrystalline glass, a preparation method thereof, and a method for regulating fluorescence properties. The glass composition and preparation method of the present invention are simple, and microcrystallization can be achieved by cooling the glass melt at room temperature. No microcrystallization heat treatment step is required, which reduces energy consumption and is low in cost. The microcrystalline glass prepared by the present invention has a fluorescent function and can stably emit light under ultraviolet light excitation. It can be used in LED light-emitting devices, displays, artistic decoration and other fields. The present invention adjusts the relative content of calcium fluoride and zirconium oxide in the glass matrix to achieve spontaneous crystal precipitation during the cooling of the glass liquid, change the type and content of the precipitated crystals, thereby achieving regulation of the glass structure and its fluorescence properties; at the same time, the fluorescence properties can be regulated by regulating the excitation wavelength.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical functional glass, and in particular relates to a Eu-doped fluorescent microcrystalline glass, a preparation method thereof, and a fluorescence performance control method. Background Art

[0002] Glass-ceramics is a multiphase material containing a microcrystalline phase and a glass phase. Currently, rare earth and transition metal co-doped glass-ceramics have found some applications. Calcium fluoride is abundant in nature and has low refractive index and low density, making it a suitable material for luminescent host materials. The presence of calcium fluoride in glass not only acts as a nucleating agent to form crystals, but also enhances luminescence efficiency by reducing the non-radiative transition losses of luminescent ions in the glass. Zirconia crystals are often used as optical materials due to their high hardness and refractive index, wide optical band gap, low optical loss, and high transparency from the near-infrared to the visible light. Zirconia has three crystal structures: monoclinic, tetragonal, and cubic. However, only the monoclinic phase is stable at room temperature. Studies have shown that doping zirconia with certain oxides, such as calcium oxide, magnesium oxide, and yttrium oxide, can prevent tetragonal and cubic zirconia crystals from transforming into the monoclinic phase.

[0003] Eu-doped light-converting fluorescent microcrystalline glass has application value in the fields of LED light-emitting devices, artistic decoration, color display, etc. The currently commonly used technology for regulating the fluorescence properties of microcrystalline glass is mainly to regulate it by subjecting the base glass to microcrystallization heat treatment to precipitate a crystal. The above method requires a high temperature, high energy consumption, high cost, and cumbersome preparation method. For example, Chinese patent document CN106517797A discloses a microcrystalline glass that can be applied to warm white light LEDs and its preparation process. This warm white light LED microcrystalline glass uses SiO2, B2O3 and Al2O3 to form the main network skeleton components of the glass; Li2O, Na2O, K2O as glass network modifiers; ZrO2 and TiO2 as glass nucleating agents; BaCO3, Y2O3, SiO2 and BaF2 are components of the target precipitated crystal phase; and Eu ions as doped white light emitting centers. The invention provides a glass-ceramic for warm white LEDs that emits warm white light when excited by 350-nanometer ultraviolet light. This glass-ceramic can be used as a fluorescent material to construct white LEDs excited by ultraviolet chips. When powered, it emits warm white light under (near) ultraviolet light. However, the preparation of this glass-ceramic requires high temperatures, consumes a lot of energy, and is costly, and does not involve the regulation of luminescence properties. Chinese patent document CN101381204A discloses a fluorescent glass-ceramic and a method for its preparation. The CaO-MgO-SiO2 fluorescent microcrystalline glass is prepared from raw materials including CaO, MgO, SiO2, Al2O3, B2O3, ZnO, Na2O, ZrO2 and Eu2O3; the molar percentage of each raw material is: CaO 19%, MgO 16%, SiO2 58%, Al2O3 3%, B2O31.5%, ZnO1.5%, Na2O 0.5%, ZrO2 0.4%, Eu2O3 0.1%. The preparation method is to first prepare glass by melting method, and obtain microcrystalline glass containing tiny grains after heat treatment. The fluorescent microcrystalline glass obtained by this method has both good luminescence properties of crystal materials and excellent stability of glass materials. It can be used in white light LED devices to solve the problem of poor color stability of current white light LEDs. However, in order to obtain Eu 2+ ions, a reducing atmosphere was used during melting, the preparation process was relatively complicated, required a higher temperature, high energy consumption, high cost, and did not involve the regulation of luminescence performance. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a Eu-doped fluorescent microcrystalline glass, its preparation method and fluorescence performance control method. The glass composition and preparation method of the present invention are simple, and microcrystallization can be achieved by cooling the glass melt at room temperature. There is no need for microcrystallization heat treatment steps, which reduces energy consumption and has low costs. The microcrystalline glass prepared by the present invention has a fluorescent function and can stably emit light under ultraviolet light excitation. It can be used in LED light-emitting devices, displays and artistic decorations. The present invention uses SiO2-B2O3-Al2O3-CaF2-ZrO2-Na2O system glass as a matrix, and rare earth Eu 3+ / Eu 2+ As the luminescence center, by adjusting the relative contents of calcium fluoride and zirconium oxide in the glass matrix, spontaneous crystal precipitation during the cooling of the glass liquid is achieved, and the type and content of the precipitated crystals are changed, thereby achieving the regulation of the glass structure and its fluorescence properties; at the same time, the fluorescence properties can also be regulated by adjusting the excitation wavelength.

[0005] In order to achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] A Eu-doped fluorescent glass-ceramic, comprising the following components in molar fractions:

[0007] SiO2: 30-50 parts, B2O3: 5-15 parts, Al2O3: 2-8 parts, microcrystalline phase component: 1-30 parts, Na2O: 10-20 parts, Eu2O3: 0.01-0.1 parts; the microcrystalline phase component is one or both of CaF2 and ZrO2.

[0008] According to the preferred embodiment of the present invention, the Eu-doped fluorescent glass-ceramics comprises the following components in molar fractions:

[0009] SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, microcrystalline phase component: 1-30 parts, Na2O: 15 parts, Eu2O3: 0.05 parts.

[0010] Preferably, the Eu-doped fluorescent glass-ceramics comprises the following components in molar fractions:

[0011] SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, microcrystalline phase component: 30 parts, Na2O: 15 parts, Eu2O3: 0.05 parts.

[0012] Preferably according to the present invention, when the microcrystalline phase component is a combination of CaF2 and ZrO2, the molar ratio of ZrO2 to CaF2 is 1:5-5:1.

[0013] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0014] (1) fully grinding and uniformly mixing silicon dioxide, boric acid, aluminum oxide, a microcrystalline phase raw material, sodium carbonate, and europium oxide to obtain a glass batch; the microcrystalline phase raw material is one or a combination of calcium fluoride or zirconium oxide;

[0015] (2) melting the glass batch material to obtain molten glass;

[0016] (3) Pour the glass liquid into a preheated mold and cool it at room temperature to form it; then anneal it to obtain Eu-doped fluorescent microcrystalline glass.

[0017] According to the present invention, preferably, in step (2), the melting process is as follows: heating to 300-500°C at a heating rate of 4-6°C / min, then heating to 950-1050°C at a heating rate of 5-7°C / min, then heating to 1500-1600°C at a heating rate of 4-5°C / min, melting for 0.5-2 hours, and the melting atmosphere adopts an air atmosphere; preferably, the melting process is as follows: heating to 400°C at a heating rate of 5°C / min, then heating to 1000°C at a heating rate of 6°C / min, then heating to 1550°C at a heating rate of 4.8°C / min, and melting for 1 hour.

[0018] According to the preferred embodiment of the present invention, in step (3), the temperature of the preheated mold is 460-480°C, preferably 470°C.

[0019] According to the present invention, preferably, in step (3), the atmosphere for room temperature cooling and molding is air.

[0020] According to the preferred embodiment of the present invention, in step (3), the annealing temperature is 450-500°C, the annealing time is 1-3 hours, and the annealing atmosphere is air; preferably, the annealing temperature is 470°C, and the annealing time is 2 hours. The purpose of annealing is to reduce stress in the glass and prevent glass cracking.

[0021] Preferably, according to the present invention, under the condition that the total content of the microcrystalline phase components remains unchanged, the type and content of crystals in the glass are regulated by controlling the molar ratio of calcium fluoride and zirconium oxide, thereby achieving the regulation of the structure of the microcrystalline glass and its fluorescence properties; or, the fluorescence properties of the microcrystalline glass are regulated by changing the excitation wavelength. As the ZrO2 content increases, the content of CaF2 crystals in the glass decreases. When the molar ratio of zirconium oxide to calcium fluoride is 1:2, the glass will contain both CaF2 crystals and cubic ZrO2 crystals. When the zirconium oxide content continues to increase to a molar ratio of zirconium oxide to calcium fluoride of 1:1, the content of CaF2 crystals in the glass decreases sharply, and no ZrO2 crystals are generated; when the zirconium oxide content continues to increase, the glass contains monoclinic ZrO2 crystals and no CaF2 crystals.

[0022] The method for regulating the fluorescence properties of the Eu-doped fluorescent microcrystalline glass comprises the following steps: controlling the molar ratio of calcium fluoride to zirconium oxide while keeping the total content of the microcrystalline phase components constant, thereby regulating the type and content of crystals in the glass, thereby regulating the fluorescence properties of the microcrystalline glass; or regulating the fluorescence properties of the microcrystalline glass by changing the excitation wavelength. As the ZrO2 content increases, the content of CaF2 crystals in the glass decreases. When the molar ratio of zirconium oxide to calcium fluoride is 1:2, the glass will contain both CaF2 crystals and cubic ZrO2 crystals. When the zirconium oxide content is further increased to a molar ratio of zirconium oxide to calcium fluoride of 1:1, the content of CaF2 crystals in the glass decreases sharply, and no ZrO2 crystals are generated. When the zirconium oxide content is further increased, the glass contains monoclinic ZrO2 crystals and no CaF2 crystals.

[0023] The Eu-doped fluorescent glass-ceramics are used in artistic decoration, LED light-emitting devices or LED displays.

[0024] The technical features and beneficial effects of the present invention are as follows:

[0025] 1. The fluorescent microcrystalline glass of the present invention has a simple composition and preparation method. Microcrystallization can be achieved by cooling the glass liquid at room temperature. There is no need for basic glass microcrystallization heat treatment steps, which reduces energy consumption and is low in cost.

[0026] 2. The present invention uses SiO2-B2O3-Al2O3-CaF2-ZrO2-Na2O system glass as the matrix, rare earth Eu 3+ / Eu 2+ By adjusting the relative contents of calcium fluoride and zirconium oxide in the glass matrix, spontaneous crystal precipitation occurs during the cooling of the molten glass. The type and content of the precipitated crystals can be varied, thereby adjusting the glass structure and its fluorescence properties. Furthermore, the fluorescence properties can be controlled by adjusting the excitation wavelength. The present invention allows the spontaneous precipitation of two types of crystals during the cooling of the molten glass. By controlling the crystal type and relative content, the fluorescence properties of the material can be adjusted.

[0027] 3. Generally, you want to get Eu in the sample 2+ The invention adopts Eu2O3 as raw material to introduce europium ions, and successfully realizes Eu2O3 in air atmosphere by designing appropriate glass matrix composition. 3+ Xiang Eu 2+ The reduction of the catalyst reduces the preparation cost and increases the preparation safety.

[0028] 4. The microcrystalline glass prepared by the present invention has a fluorescent function and can emit light stably under ultraviolet light excitation, and can be used in the fields of LED light-emitting devices, displays and artistic decoration.

[0029] 5. The glass composition of the present invention is a whole. The absence, replacement or inappropriate use of any component will not achieve the excellent effect of the present invention, that is, spontaneous crystallization during cooling cannot be achieved or the amount of crystallization is small and the regulation of fluorescence performance cannot be achieved. For example, the content of B2O3, Na2O, and Al2O3 will affect crystallization. If it is not appropriate, it will inhibit crystallization. At the same time, changes in the content of B2O3 and Al2O3 will affect Eu 3+ Xiang Eu 2+ Restoration. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is the emission spectrum of the glass-ceramics prepared in Example 1 under excitation at wavelengths of 300, 320, and 362 nm.

[0031] Figure 2 This is the excitation spectrum of the glass prepared in Example 3 monitored at wavelengths of 423 and 612 nm.

[0032] Figure 3 This is the emission spectrum of the glass prepared in Example 3 under excitation at wavelengths of 300, 320 and 362 nm.

[0033] Figure 4 X-ray diffraction patterns of the glass-ceramics prepared in Examples 1, 2, 3 and 4.

[0034] Figure 5 Infrared spectra of the glass-ceramics prepared in Examples 1, 2, 3 and 4.

[0035] Figure 6 Emission spectra of the glass-ceramics prepared in Examples 1 and 3 under excitation at a wavelength of 300 nm.

[0036] Figure 7 These are the emission spectra of the glass-ceramics prepared in Examples 1, 2, 3 and 4 under excitation at a wavelength of 362 nm.

[0037] Figure 8 X-ray diffraction patterns of the glass-ceramics prepared in Examples 5, 6 and 7.

[0038] Figure 9 These are the emission spectra of the glass-ceramics prepared in Examples 5, 6 and 7 under excitation at a wavelength of 330 nm.

[0039] Figure 10 Emission spectra of the glass-ceramics prepared in Examples 1, 3 and 7 under excitation at a wavelength of 330 nm. DETAILED DESCRIPTION

[0040] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described below in conjunction with specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0041] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] Example 1

[0043] A Eu-doped fluorescent microcrystalline glass comprises the following components in molar proportions: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, CaF2: 30 parts, Na2O: 15 parts, and Eu2O3: 0.05 parts.

[0044] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0045] (1) According to the composition of the above glass, silicon dioxide, boric acid, aluminum oxide, calcium fluoride, sodium carbonate, and europium oxide are accurately weighed, and these raw materials are fully ground and mixed to obtain a glass batch.

[0046] (2) Melting: Pour the glass batch into a corundum crucible, heat it from room temperature to 400°C at a heating rate of 5°C / min, then heat it to 1000°C at a heating rate of 6°C / min, and then heat it to 1550°C at a heating rate of 4.8°C / min. Melt it at this temperature for 1 hour to obtain glass liquid. The melting atmosphere is air atmosphere.

[0047] (3) Pour the glass liquid obtained in step (2) into a copper mold preheated to 470°C, cool it to room temperature in an air atmosphere, and anneal it at 470°C for 2 hours (in an air atmosphere) to obtain microcrystalline glass.

[0048] The emission spectra of the glass-ceramics prepared in this embodiment under different wavelength excitation are as follows: Figure 1 As shown, there is a broad emission band in the emission spectrum at 360-560 nm, which is derived from Eu 2+ ions 5d-4f electronic transition, and with the change of excitation wavelength, the relative intensity and emission peak position of broadband emission also change; the emission peaks at 574nm, 592nm and 599nm, 612nm, 654nm, and 704nm are derived from Eu 3+ Ionic 5 D0- 7 F0, 5 D0- 7 F1,5 D0- 7 F2, 5 D0- 7 F3, 5 D0- 7 F4 electron transition. This embodiment uses Eu2O3 as a raw material to introduce europium ions, does not use a reducing atmosphere, and prepares microcrystalline glass in an air atmosphere. Generally, if you want to get Eu in the sample 2+ It is necessary to use a reducing atmosphere (such as H2 atmosphere, CO atmosphere) for preparation. From this embodiment, it can be seen that by designing a suitable glass matrix composition, Eu 3+ Xiang Eu 2+ The reduction of the catalyst reduces the preparation cost and increases the preparation safety.

[0049] Example 2

[0050] A Eu-doped fluorescent microcrystalline glass comprises the following components in molar proportions: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, ZrO2: 5 parts, CaF2: 25 parts, Na2O: 15 parts, and Eu2O3: 0.05 parts.

[0051] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0052] (1) According to the composition of the above glass, silicon dioxide, boric acid, aluminum oxide, calcium fluoride, zirconium oxide, sodium carbonate, and europium oxide are accurately weighed, and these raw materials are fully ground and mixed to obtain a glass batch.

[0053] (2) Melting: Pour the glass batch into a corundum crucible, heat it from room temperature to 400°C at a heating rate of 5°C / min, then heat it to 1000°C at a heating rate of 6°C / min, and then heat it to 1550°C at a heating rate of 4.8°C / min. Melt it at this temperature for 1 hour to obtain glass liquid. The melting atmosphere is air atmosphere.

[0054] (3) Pour the glass liquid obtained in step (2) into a copper mold preheated to 470°C, cool it to room temperature in an air atmosphere, and anneal it at 470°C for 2 hours (in an air atmosphere) to obtain microcrystalline glass.

[0055] Example 3

[0056] A Eu-doped fluorescent microcrystalline glass comprises the following components in molar proportions: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, ZrO2: 10 parts, CaF2: 20 parts, Na2O: 15 parts, and Eu2O3: 0.05 parts.

[0057] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0058] (1) According to the composition of the above glass, silicon dioxide, boric acid, aluminum oxide, calcium fluoride, zirconium oxide, sodium carbonate, and europium oxide are accurately weighed, and these raw materials are fully ground and mixed to obtain a glass batch.

[0059] (2) Melting: Pour the glass batch into a corundum crucible, heat it from room temperature to 400°C at a heating rate of 5°C / min, then heat it to 1000°C at a heating rate of 6°C / min, and then heat it to 1550°C at a heating rate of 4.8°C / min. Melt it at this temperature for 1 hour to obtain glass liquid. The melting atmosphere is air atmosphere.

[0060] (3) Pour the glass liquid obtained in step (2) into a copper mold preheated to 470°C, cool it to room temperature in an air atmosphere, and anneal it at 470°C for 2 hours (in an air atmosphere) to obtain microcrystalline glass.

[0061] The excitation spectra of the glass-ceramics prepared in this example under the monitoring of wavelengths of 423 and 612 nm are as follows: Figure 2 The excitation spectrum obtained at 423 nm is obtained by Eu 2+ The excitation spectrum under 612nm wavelength monitoring shows excitation peaks at 362, 382, ​​394, and 464nm, corresponding to Eu 3+ Ionic 7 F0- 5 D4, 7 F0- 5 G2, 7 F0- 5 L6 and 7 F0- 5 D2 electronic transition. The emission spectra of the glass-ceramics prepared in this embodiment at different excitation wavelengths are as follows: Figure 3 As shown, the figure shows Eu 2+ and Eu 3+ The broad emission band at 380-570 nm originates from Eu 2+ ions 5d-4f electronic transition. With the increase of excitation wavelength, the peak of the broad emission band produces a blue shift phenomenon. The emission peak positions are 470nm (λex=300nm), 430nm (λex=320nm), 423nm (λex=362nm), and the relative intensity increases accordingly. The emission peaks at 578, 592, 612, 631, 654, and 704nm are derived from Eu 3+ This shows that the luminescence properties of the glass-ceramics prepared in this embodiment can be regulated by changing the excitation wavelength.

[0062] Example 4

[0063] A Eu-doped fluorescent microcrystalline glass comprises the following components in molar proportions: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, ZrO2: 15 parts, CaF2: 15 parts, Na2O: 15 parts, and Eu2O3: 0.05 parts.

[0064] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0065] (1) According to the composition of the above glass, silicon dioxide, boric acid, aluminum oxide, calcium fluoride, zirconium oxide, sodium carbonate, and europium oxide are accurately weighed, and these raw materials are fully ground and mixed to obtain a glass batch.

[0066] (2) Melting: Pour the glass batch into a corundum crucible, heat it from room temperature to 400°C at a heating rate of 5°C / min, then heat it to 1000°C at a heating rate of 6°C / min, and then heat it to 1550°C at a heating rate of 4.8°C / min. Melt it at this temperature for 1 hour to obtain glass liquid. The melting atmosphere is air atmosphere.

[0067] (3) Pour the glass liquid obtained in step (2) into a copper mold preheated to 470°C, cool it to room temperature in an air atmosphere, and anneal it at 470°C for 2 hours (in an air atmosphere) to obtain microcrystalline glass.

[0068] The X-ray diffraction patterns of the glass-ceramics prepared in Examples 1, 2, 3 and 4 are as follows: Figure 4 As shown. The spectra of Examples 1, 2, 3 and 4 have the same diffraction peaks, corresponding to CaF2 crystals (PDF 35-0816). Example 3 has some more diffraction peaks than Examples 1, 2 and 4. These diffraction peaks correspond to cubic ZrO2 crystals (PDF 49-1642). As the ZrO2 content increases, the amount of CaF2 crystals precipitated decreases. When the ratio of zirconium oxide to calcium fluoride is 1:2 (Example 3), CaF2 crystals and cubic ZrO2 crystals are generated in the sample at the same time. When the ratio of zirconium oxide to calcium fluoride is 1:1 (Example 4), the content of CaF2 crystals in the sample decreases sharply, and no ZrO2 crystals are generated. Generally, when crystals are precipitated in glass, they need to be subjected to microcrystallization heat treatment. From Figure 4 It can be seen from the X-ray diffraction results in that by precisely designing the glass matrix composition, the precipitation of a single crystal and the simultaneous precipitation of two crystals during the cooling of the glass melt can be achieved.

[0069] The infrared spectra of the glasses prepared in Examples 1, 2, 3 and 4 are as follows: Figure 5As shown in the figure, there are four main absorption bands. Absorption band 1 corresponds to BO symmetric stretching vibration, absorption band 2 corresponds to BO asymmetric stretching vibration, absorption band 3 corresponds to Al-O bending vibration, absorption band 4 corresponds to Si-O-Si and Si-O-Al bending vibrations, and absorption band 5 is due to the stretching vibration of the OH group caused by the introduction of water when preparing the KBr pellets used for Fourier transform infrared spectroscopy measurements. As can be seen from the figure, the position and intensity of each absorption band also change by changing the matrix glass composition, indicating that the glass structure has changed, resulting in changes in luminescence properties.

[0070] The emission spectra of the glass-ceramics prepared in Examples 1 and 3 at 300 nm excitation are as follows: Figure 6 As shown. It can be seen that the Eu 3+ The luminescence is lower than Eu 2+ , while Example 3 is derived from Eu 3+ The luminescence is higher than Eu 2+ This shows that Examples 1 and 3Eu 3+ Xiang Eu 2+ The degree of conversion varies. Figure 4 The X-ray diffraction patterns show that Example 1 primarily contains CaF2 crystals, while Example 3 primarily contains CaF2 crystals and cubic ZrO2 crystals. This demonstrates that by varying the relative amounts of CaF2 and ZrO2 in the glass matrix, the type of crystals in the prepared material can be adjusted, thereby regulating the luminescence properties of the material.

[0071] The emission spectra of the glass-ceramics prepared in Examples 1, 2, 3 and 4 under 362 nm wavelength excitation are as follows: Figure 7 As shown, the emission spectrum contains Eu 2+ and Eu 3+ With the increase of zirconium oxide content, the emission peak from Eu 2+ The emission peak intensity gradually decreases.

[0072] Example 5

[0073] A Eu-doped fluorescent microcrystalline glass comprises the following components in molar proportions: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, ZrO2: 20 parts, CaF2: 10 parts, Na2O: 15 parts, and Eu2O3: 0.05 parts.

[0074] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0075] (1) According to the composition of the above glass, silicon dioxide, boric acid, aluminum oxide, calcium fluoride, zirconium oxide, sodium carbonate, and europium oxide are accurately weighed, and these raw materials are fully ground and mixed to obtain a glass batch.

[0076] (2) Melting: Pour the glass batch into a corundum crucible, heat it from room temperature to 400°C at a heating rate of 5°C / min, then heat it to 1000°C at a heating rate of 6°C / min, and then heat it to 1550°C at a heating rate of 4.8°C / min. Melt it at this temperature for 1 hour to obtain glass liquid. The melting atmosphere is air atmosphere.

[0077] (3) Pour the glass liquid obtained in step (2) into a copper mold preheated to 470°C, cool it to room temperature in an air atmosphere, and anneal it at 470°C for 2 hours (in an air atmosphere) to obtain microcrystalline glass.

[0078] Example 6

[0079] A Eu-doped fluorescent microcrystalline glass comprises the following components in molar proportions: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, ZrO2: 25 parts, CaF2: 5 parts, Na2O: 15 parts, and Eu2O3: 0.05 parts.

[0080] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0081] (1) According to the composition of the above glass, silicon dioxide, boric acid, aluminum oxide, calcium fluoride, zirconium oxide, sodium carbonate, and europium oxide are accurately weighed, and these raw materials are fully ground and mixed to obtain a glass batch.

[0082] (2) Melting: Pour the glass batch into a corundum crucible, heat it from room temperature to 400°C at a heating rate of 5°C / min, then heat it to 1000°C at a heating rate of 6°C / min, and then heat it to 1550°C at a heating rate of 4.8°C / min. Melt it at this temperature for 1 hour to obtain glass liquid. The melting atmosphere is air atmosphere.

[0083] (3) Pour the glass liquid obtained in step (2) into a copper mold preheated to 470°C, cool it to room temperature in an air atmosphere, and anneal it at 470°C for 2 hours (in an air atmosphere) to obtain microcrystalline glass.

[0084] Example 7

[0085] A Eu-doped fluorescent microcrystalline glass comprises the following components in molar proportions: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, ZrO2: 30 parts, Na2O: 15 parts, and Eu2O3: 0.05 parts.

[0086] The method for preparing the Eu-doped fluorescent glass-ceramics comprises the following steps:

[0087] (1) According to the composition of the above glass, silicon dioxide, boric acid, aluminum oxide, zirconium oxide, sodium carbonate, and europium oxide are accurately weighed, and these raw materials are fully ground and mixed to obtain a glass batch.

[0088] (2) Melting: Pour the glass batch into a corundum crucible, heat it from room temperature to 400°C at a heating rate of 5°C / min, then heat it to 1000°C at a heating rate of 6°C / min, and then heat it to 1550°C at a heating rate of 4.8°C / min. Melt it at this temperature for 1 hour to obtain glass liquid. The melting atmosphere is air atmosphere.

[0089] (3) Pour the glass liquid obtained in step (2) into a copper mold preheated to 470°C, cool it to room temperature in an air atmosphere, and anneal it at 470°C for 2 hours (in an air atmosphere) to obtain microcrystalline glass.

[0090] The X-ray diffraction patterns of the glass-ceramics prepared in Examples 5, 6 and 7 are as follows: Figure 8 As shown in the figure, the materials prepared in these three examples all have obvious diffraction peaks, corresponding to monoclinic ZrO2 crystals (PDF 37-1484), and the diffraction peak intensity increases in the order of Examples 5, 6, and 7, indicating that the crystal content in these three samples increases successively.

[0091] The emission spectra of the glass-ceramics prepared in Examples 5, 6 and 7 under 330 nm wavelength excitation are as follows: Figure 9 As shown. The spectrum shows Eu 2+ and Eu 3+ The broad emission band at 400-570 nm originates from Eu 2+ It can be seen that with the increase of zirconium oxide content, Eu 2+ The relative intensity of the emission band gradually increases, and the emission peak position blue-shifts (507nm→500nm→493nm). Figure 8 The X-ray diffraction patterns show that Examples 5, 6, and 7 all contain monoclinic ZrO2 crystals, and the crystal content increases in sequence. 2+ The relative emission intensity increases.

[0092] Figure 10 The emission spectra of the materials prepared in Examples 1, 3, and 7 at an excitation wavelength of 330 nm are shown. 3+ The relative emission intensity of the ions is very low, and compared with Examples 1 and 3, the Eu 2+ The emission peak of the ion is obviously red-shifted. Figure 4 and Figure 8The X-ray diffraction patterns show that Examples 1, 3, and 7 contain CaF2 crystals, CaF2 crystals / cubic ZrO2 crystals, and monoclinic ZrO2 crystals, respectively. By varying the relative amounts of CaF2 and ZrO2 in the sample composition, we can adjust the type and amount of crystals in the prepared materials, thereby regulating the fluorescence properties of the materials.

[0093] Table 1 Color coordinates of fluorescent glass-ceramics

[0094]

[0095] Table 1 lists the color coordinates of some embodiments of the present invention. It can be seen that the color coordinates of the glass-ceramics of the present invention can be adjusted by the glass matrix composition, crystallization type and content, glass structure and excitation wavelength, so that the fluorescent glass-ceramics can be adapted to different application environments.

[0096] This invention produces Eu-doped fluorescent glass-ceramics by cooling a high-temperature melt. By varying the relative contents of CaF2 and ZrO2 in the glass matrix, the type and content of crystallization, the glass structure, and the fluorescent properties of the material can be adjusted. The glass-ceramics of this invention are suitable for applications in artistic decoration, LED light-emitting devices, color displays, and other fields.

[0097] The above description is merely a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any person skilled in the art may utilize the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes for application in other fields. However, any simple modification, equivalent change, and modification of the above embodiments made in accordance with the technical essence of the present invention without departing from the technical solution of the present invention shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A Eu-doped fluorescent glass-ceramic, characterized in that: The following components are included in molar fractions: composition: SiO2: 30-50 parts, B2O3: 5-15 parts, Al2O3: 2-8 parts, microcrystalline phase components: 1-30 parts, Na2O: 10-20 parts, Eu2O3: 0.01-0.1 parts; the microcrystalline phase components are a combination of CaF2 and ZrO2, and the molar ratio of ZrO2 to CaF2 is 1:5-5:

1.

2. The Eu-doped fluorescent glass-ceramics according to claim 1, characterized in that: Eu-doped fluorescent glass-ceramics includes the following components in molar fractions: composition: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, microcrystalline phase component: 1-30 parts, Na2O: 15 parts, Eu2O3: 0.05 parts.

3. The Eu-doped fluorescent glass-ceramics according to claim 2, characterized in that: Eu-doped fluorescent glass-ceramics includes the following components in molar fractions: composition: SiO2: 40 parts, B2O3: 10 parts, Al2O3: 5 parts, microcrystalline phase component: 30 parts, Na2O: 15 parts, Eu2O3: 0.05 parts.

4. The method for preparing the Eu-doped fluorescent glass-ceramics according to any one of claims 1 to 3, comprising the steps of: (1) Grinding silicon dioxide, boric acid, aluminum oxide, microcrystalline raw material, sodium carbonate, and europium oxide thoroughly and mixing them uniformly to obtain a glass batch; the microcrystalline raw material is calcium fluoride or zirconium oxide, or a combination of the two; (2) Melting the glass batch material to obtain molten glass; (3) Pour the glass liquid into a preheated mold and cool it at room temperature to form it; then anneal it to obtain Eu-doped fluorescent microcrystalline glass.

5. The method for preparing Eu-doped fluorescent glass-ceramics according to claim 4, characterized in that: In step (2), the melting process is as follows: heating to 300-500°C at a heating rate of 4-6°C / min, then heating to 950-1050°C at a heating rate of 5-7°C / min, and then heating to 1500-1600°C at a heating rate of 4-5°C / min, melting for 0.5-2 hours, and the melting atmosphere adopts air atmosphere.

6. The method for preparing Eu-doped fluorescent glass-ceramics according to claim 4, characterized in that: In step (3), one or more of the following conditions are included: i. The temperature of the preheated mold is 460-480℃; ii. The atmosphere for room temperature cooling molding is air; iii. The annealing temperature is 450-500°C, the annealing time is 1-3 hours, and the annealing atmosphere is air.

7. The method for preparing Eu-doped fluorescent glass-ceramics according to claim 4, characterized in that: By controlling the molar ratio of calcium fluoride and zirconium oxide while keeping the total content of the microcrystalline phase components unchanged, the type and content of crystals in the glass can be regulated, thereby regulating the structure of the microcrystalline glass and its fluorescence properties; or, by changing the excitation wavelength, the fluorescence properties of the microcrystalline glass can be regulated.

8. The method for regulating the fluorescence properties of Eu-doped fluorescent microcrystalline glass as described in any one of claims 1 to 3 comprises the steps of: controlling the molar ratio of calcium fluoride and zirconium oxide while keeping the total content of microcrystalline phase components unchanged, thereby regulating the type and content of crystals in the glass, thereby regulating the fluorescence properties of the microcrystalline glass; or regulating the fluorescence properties of the microcrystalline glass by changing the excitation wavelength.

9. Application of the Eu-doped fluorescent glass-ceramics as claimed in any one of claims 1 to 3 in artistic decoration, LED light-emitting devices or LED displays.

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