Glass-ceramics, method for preparing the same and use thereof

Abstract

The application belongs to the technical field of luminescent materials, and discloses a glass ceramic and a preparation method and application thereof. 13 :Eu 2+ The glass ceramic provided by the application has a single crystal phase glass ceramic with a chemical formula of Al6Si2O The glass ceramic provided by the application has photoluminescence, long-afterglow luminescence, thermal excitation luminescence and photoexcitation luminescence, good luminescent performance, high temperature stability, and potential application value in the field of optical information storage. The application further provides a preparation method and application of the glass ceramic.

Description

Technical Field

[0001] This application belongs to the field of luminescent materials technology, and specifically relates to a glass ceramic and its preparation method and application. Background Technology

[0002] Rare earth-doped luminescent materials are widely used in display lighting, optical information storage, X-ray irradiation, multidimensional stress sensing, and biomedical imaging due to their unique optical properties.

[0003] Currently, research on rare-earth-doped luminescent materials mainly focuses on inorganic phosphors, fluorescent glasses, fluorescent ceramics, and fluorescent glass-ceramics. Phosphors typically need to be encapsulated in polymer matrices for application; however, organic polymer matrices are prone to photothermal degradation, limiting their applicability in extreme environments. Furthermore, phosphors are frequently plagued by thermal aging and color drift issues. Fluorescent glasses suffer from low luminescence efficiency due to their amorphous structure, while fluorescent ceramics, although exhibiting excellent performance, face challenges in preparing transparent ceramics due to stringent conditions, complex processes, and high costs.

[0004] With the continuous surge in global data volume, increasingly stringent requirements have been placed on the storage and protection of data requiring long-term preservation and secure encryption. Due to limitations such as susceptibility to electromagnetic interference and high long-term maintenance costs, traditional magnetic storage media struggle to meet the demands for long-term secure data archiving. Against this backdrop, the development of new encryption media has become a significant trend. Optical information storage, with its advantages of multi-dimensional information encryption and storage capabilities, long lifespan, and resistance to electromagnetic interference, is considered an important direction for next-generation high-density information anti-counterfeiting and secure storage. However, early single-mode optical storage carriers relied on materials with a single fluorescence characteristic, resulting in only one dimension of response. Therefore, the stored information is easily copied and forged, leading to limited security performance. To address this security risk, multi-mode luminescent media have emerged. Glass-ceramic materials with multiple luminescence modes combine the energy storage capacity of traps, enabling versatile luminescence responses to various external stimuli. This allows them to meet long-term information storage needs while simultaneously achieving information encryption and leakage detection, demonstrating potential application value in the field of optical information storage. Summary of the Invention

[0005] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a glass-ceramic, its preparation method, and its applications. This glass-ceramic exhibits multiple luminescence modes, excellent quantum efficiency, good thermal stability, and a suitable defect energy level (0.6 eV), making it suitable for optical information storage applications.

[0006] A first aspect of this application provides a glass-ceramic material comprising the chemical formula Al6Si2O. 13 Eu2 + Single-phase glass-ceramics.

[0007] In some embodiments, in the glass-ceramic, Eu 2+ The molar percentage of the single-crystal glass-ceramic is 0.8% to 2.0%. Specifically, it could be 0.8%, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, or 2.0%; or a range consisting of any two of the above values. In some embodiments, the glass-ceramic exhibits photoluminescence, with an excitation spectrum in the range of 250–400 nm and an emission spectrum peak at 447 ± 2 nm.

[0008] In some embodiments, the glass-ceramic has a long afterglow luminescence of ≥30 min and thermally excited luminescence and photoexcited luminescence.

[0009] In some embodiments, the quantum efficiency of photoluminescence of the glass-ceramic is ≥90%.

[0010] In some embodiments, the luminescence intensity of the glass ceramic at 300K is E1, at 390K it is E2, and at 480K it is E3; and E2 / E1≥85%, for example, it can be 85.5% or 86%; E3 / E1≥70%, for example, it can be 70.5% or 71%.

[0011] A second aspect of this application provides a method for preparing the glass-ceramic described in the first aspect of this application, comprising the following steps: A magnesium source, an aluminum source, a silicon source, and an europium source are mixed, and the resulting mixture is melted in a reducing atmosphere and slowly cooled to obtain the glass-ceramic.

[0012] In some embodiments, the method for preparing the amorphous glass precursor of the glass-ceramic includes the following steps: Magnesium, aluminum, silicon and europium sources are mixed, and the resulting mixture is melted in a reducing atmosphere and rapidly cooled to obtain the glass ceramic.

[0013] In some embodiments, the melting temperature is 1500-1600°C. Specifically, it could be 1500°C, 1550°C, 1600°C; or a range consisting of any two of these values. When the melting temperature is below 1500°C, such as 1400°C, a fully molten state cannot be achieved, and block-shaped glass-ceramics cannot be obtained.

[0014] In some embodiments, the melting time is 3-4 hours. For example, it can be 3 hours, 3.5 hours, 4 hours; or a range of values ​​consisting of any two of the above points.

[0015] In some embodiments, the slow cooling rate is 1-5°C / min. For example, it could be 1°C / min, 2°C / min, 3°C / min, 4°C / min, 5°C / min; or a range of values ​​consisting of any two of the above points.

[0016] In some embodiments, the rapid cooling rate is 25-30°C / min. For example, it can be 25°C / min, 26°C / min, 27°C / min, 28°C / min, 29°C / min, 30°C / min; or a range of values ​​consisting of any two of the above points.

[0017] In some embodiments, the reducing atmosphere is provided independently by at least one of toner and hydrogen.

[0018] When using toner in this application, the toner is placed outside the mixture to be heated, so that the toner can react with the residual air (mainly oxygen) in the furnace to generate reducing gases such as carbon monoxide, thereby providing a reducing environment.

[0019] In some embodiments, the mixing method includes grinding.

[0020] In some implementations, the mixing time is 20-30 minutes.

[0021] In some embodiments, the magnesium source includes magnesium oxide (MgO).

[0022] In some embodiments, the aluminum source includes aluminum oxide (Al2O3).

[0023] In some embodiments, the silicon source includes silicon oxide (SiO2).

[0024] In some embodiments, the europium source includes europium oxide (Eu2O3).

[0025] In some embodiments, the glass-ceramic comprises the following raw materials in molar fractions: SiO2 40-60%, Al2O3 10-30%, MgO 10-30%, and Eu2O3 0.8-2%. MgO, in this application, acts as a network modifier to improve the degree of network depolymerization, has a certain fluxing and crystallization-promoting effect, and functions as a glass network modifier. It can improve the degree of glass depolymerization, exists in the glass phase, but does not enter the crystal; without the addition of MgO, it cannot be completely melted, and a bulk glass-ceramic cannot be obtained.

[0026] A third aspect of this application provides the application of the glass ceramics described in the first aspect of this application, or the glass ceramics prepared by the preparation method described in the second aspect of this application, in the field of optical information storage.

[0027] Compared with the prior art, the beneficial effects of this application are as follows: (1) The glass ceramic provided in this application is dense and hard due to the optimization of the composition. It has good physical and chemical stability. It still has a luminous performance of more than 70% of the initial luminous intensity at a high temperature of 200℃, and the quantum efficiency at room temperature can be greater than 95%. It exhibits bright blue light emission under ultraviolet excitation.

[0028] (2) The glass ceramic provided in this application has four light emission modes: photoluminescence, long afterglow emission, thermally excited emission, and light-excited emission, which broadens its practical application scenarios and is expected to be applied in the field of optical information storage.

[0029] (3) The preparation method of the glass-ceramic material of this application is simple, safe and inexpensive. Attached Figure Description

[0030] Figure 1 This is the XRD pattern of the precursor glass prepared in Example 1 of this application; Figure 2 This is a photograph of the precursor glass obtained in Embodiment 1 of this application; Figure 3 This is the normalized excitation and emission spectrum of the precursor glass prepared in Example 1 of this application; Figure 4 This is the XRD pattern of the glass-ceramic prepared in Example 2 of this application; Figure 5 This is a scanning electron microscope (SEM) image of the glass-ceramic obtained in Example 2 of this application; Figure 6 This is the room temperature normalized excitation and emission spectrum of the glass-ceramic prepared in Example 2 of this application; Figure 7 This is the temperature-varying fluorescence spectrum of the glass-ceramic prepared in Example 2 of this application in the temperature range of 300-480K; Figure 8 This is the photoluminescence absolute fluorescence quantum yield test spectrum of the glass-ceramic prepared in Example 2 of this application; Figure 9 This is a test curve of the long afterglow luminescence performance of the glass-ceramic prepared in Example 2 of this application; Figure 10 This is a three-dimensional pyroelectric spectrum of the glass-ceramic prepared in Example 2 of this application; Figure 11 This is the luminescence performance test spectrum of the glass-ceramic obtained by Example 2 of this application under 980nm near-infrared light excitation. Figure 12 This is an example diagram of the application of the glass-ceramic optical information storage obtained in Embodiment 2 of this application. Detailed Implementation

[0031] The following specific embodiments further illustrate the content of this application in detail. Unless otherwise specified, the raw materials, reagents, or apparatus used in the embodiments can be obtained from conventional commercial sources or by existing technical methods. Unless otherwise specified, the experimental or testing methods are conventional methods in the art.

[0032] In this application, room temperature refers to 25±2℃.

[0033] Example 1 This example demonstrates the preparation of a precursor glass. The specific preparation steps are as follows: S1. Mix and grind 50% SiO2, 25% Al2O3, 25% MgO, and 0.8% Eu2O3 (total molar fraction of SiO2, Al2O3 and MgO) for 30 minutes. Place the uniformly mixed raw materials in a corundum crucible. S2. Place the corundum crucible containing the raw materials in a reducing atmosphere (carbon powder is used in this example), melt it in a box furnace at 1600°C for 3 hours, then quickly remove it and rapidly cool the melt (cooling rate is 30°C / min). After cooling to room temperature, the precursor amorphous glass is obtained.

[0034] The precursor glass is the precursor state of the glass-ceramic in this application. The glass-ceramic is the material after crystallization of the precursor glass. The precursor glass provides an amorphous control group for the glass-ceramic, which facilitates comparison of the differences before and after the phase transition through testing.

[0035] The X-ray diffraction peaks show that the precursor glass prepared in Example 1 exhibits amorphous peaks, with no crystalline diffraction peaks, indicating that amorphous glass was successfully prepared (see [link to X-ray diffraction chart]). Figure 1 The precursor glass produced still exhibits excellent transparency at a thickness of 1 mm; under 340 nm ultraviolet excitation, the precursor glass displays bright blue luminescence (see...). Figure 2 Normalized excitation and emission spectra at room temperature were measured using an Edinburgh FS980 fluorescence spectrometer (see [reference]). Figure 3 Eu can be observed 2+ It exhibits typical broad-peak emission with a central wavelength of 438 nm.

[0036] Example 2 This example demonstrates the preparation of a glass-ceramic comprising Al6Si2O 13 Eu 2+ The specific preparation steps for the single-crystal phase glass-ceramic are as follows: S1. Mix and grind 50% SiO2, 25% Al2O3, 25% MgO, and 0.8% Eu2O3 (total molar fraction of SiO2, Al2O3 and MgO) for 30 minutes. Place the uniformly mixed raw materials in a corundum crucible. S2. Place the corundum crucible containing the raw materials in a reducing atmosphere (carbon powder is used in this example), melt it in a box furnace at 1600°C for 3 hours, and then slowly cool it with the furnace (cooling rate is 5°C / min). After cooling to room temperature, glass ceramic is obtained.

[0037] The X-ray diffraction peaks show that the crystal diffraction peaks of the prepared glass-ceramic are similar to those of Al6Si2O. 13 The PDF standard card corresponds well, proving that Al6Si2O has been precipitated. 13 Single crystal phase (see) Figure 4 The glass-ceramic with micron-sized crystals was successfully fabricated using scanning electron microscopy (SEM). (See [link to SEM document]) Figure 5 The prepared glass-ceramic exhibited bright blue luminescence under ultraviolet excitation at a wavelength of 340 nm. Its normalized excitation and emission spectra at room temperature were measured using an Edinburgh FS980 fluorescence spectrometer (see [reference]). Figure 6 Eu can be observed 2+ Typical broad-peak emission, with the emission center wavelength located at 447 nm. The glass-ceramic was tested at varying temperatures from 300 to 480 K (see [reference]). Figure 7 It can be visually observed that the material retains 71% of its initial luminescence intensity at a high temperature of 480K, indicating that the glass-ceramic prepared in this application has good thermal stability. The photoluminescence quantum efficiency of the prepared glass-ceramic was measured using a C13534 ultraviolet-near-infrared absolute fluorescence quantum yield spectrometer (see [reference]). Figure 8 ), Figure 8 The blank control in the test was a BaSO4 standard white plate reference sample; the test results showed that the quantum efficiency of the glass ceramic prepared in Example 2 was as high as 97.3%.

[0038] The long afterglow performance of the glass-ceramic prepared in Example 2 was tested using an Edinburgh FS980 fluorescence spectrometer (see [reference]). Figure 9 It can be seen that the prepared glass-ceramic exhibits a long afterglow luminescence performance exceeding 30 minutes. The thermally excited luminescence performance of the glass-ceramic prepared in Example 2 was tested using a Linkmann Scientific Instruments TMHSE 6300 thermoluminescence analyzer. The 3D thermoluminescence spectrum shows (see...) Figure 10The resulting glass-ceramic exhibits significant thermoluminescence, with blue light emitted. Thermoluminescence spectroscopy calculations indicate that the glass-ceramic possesses a trap level depth of 0.6 eV, demonstrating relatively stable electron storage capability at room temperature. The photoluminescence properties of the glass-ceramic prepared in Example 2 were tested using an Edinburgh FS980 fluorescence spectrometer (see [link to relevant documentation]). Figure 11 As can be seen, after the afterglow disappears, irradiation with a 980nm near-infrared laser results in a significant luminescence response in the fabricated glass-ceramic, proving that the fabricated glass-ceramic possesses photoluminescence characteristics, and that the photoluminescence is blue. Based on these luminescence characteristics, Figure 12 An example of optical information storage application is given, which involves writing information under ultraviolet light and reading information by heating.

[0039] In summary, this application utilizes a melt self-crystallization method to prepare a doped Eu material. 2+ Multimodal glass-ceramic materials using rare earth ions: This method is low-cost, simple, and suitable for mass production. By controlling the cooling rate, precursor amorphous glass and Al6Si2O can be obtained separately. 13 Eu 2+ This glass-ceramic exhibits blue photoluminescence under ultraviolet excitation, good thermal stability, and a quantum yield of up to 97.3%. It also boasts a long afterglow emission performance exceeding 30 minutes, thermoluminescence with blue emission, and good optical information storage capabilities (trap level 0.6 eV). Furthermore, it displays photoluminescence excited by near-infrared excitation at 980 nm, making it a promising candidate for applications in optical information storage.

[0040] In addition, different matrices are doped with Eu 2+ There may be differences in the color of light emitted, light emission performance, and light emission mode, for example, glass-ceramic Mg2Al4Si5O 18 Eu 2+ It exhibits red light emission but lacks long-afterglow luminescence, thermoluminescence, and photoluminescence phenomena, failing to achieve multimodal luminescence. This application presents Al6Si2O prepared through composition optimization. 13 Eu 2+ Glass ceramics have four emission modes: photoluminescence, long afterglow emission, thermally excited emission, and photo-excited emission.

[0041] The preferred embodiments of this application have been described in detail above, but the invention of this application is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of this application, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A glass-ceramic, characterized in that, The glass-ceramic comprises Al6Si2O. 13 Eu 2+ Single-phase glass-ceramics.

2. The glass-ceramic according to claim 1, characterized in that, In the glass-ceramic, Eu 2+ The molar percentage of the single-crystal glass-ceramic is 0.8% to 2.0%.

3. The glass-ceramic according to claim 1, characterized in that, The glass-ceramic exhibits photoluminescence, with an excitation spectrum in the range of 250~400nm and an emission spectrum peak at 447±2nm.

4. The glass-ceramic according to claim 1, characterized in that, The glass-ceramic exhibits long afterglow luminescence of ≥30 min and thermal and photoluminescence.

5. The glass-ceramic according to claim 3, characterized in that, The quantum efficiency of photoluminescence in the glass-ceramic is ≥90%; And / or, the luminescence intensity of the glass ceramic at 300K is E1, at 390K it is E2, and at 480K it is E3; and E2 / E1≥85%; E3 / E1≥70%.

6. A method for preparing a glass-ceramic as described in any one of claims 1-5, characterized in that, Includes the following steps: A magnesium source, an aluminum source, a silicon source, and an europium source are mixed, and the resulting mixture is melted in a reducing atmosphere and slowly cooled to obtain the glass-ceramic.

7. The preparation method according to claim 6, characterized in that, The melting temperature is 1500-1600℃; and / or the melting time is 3-4 hours.

8. The preparation method according to claim 6, characterized in that, The slow cooling rate is 1-5°C / min.

9. The preparation method according to claim 6, characterized in that, The reducing atmosphere is provided independently by at least one of carbon powder and hydrogen.

10. The application of a glass-ceramic as described in any one of claims 1-5, or a glass-ceramic prepared by any one of claims 6-9, in the field of optical information storage.

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