Blue-light microcrystalline glass capable of being excited by purple light as well as preparation method and application of blue-light microcrystalline glass

Abstract

The invention discloses blue-light microcrystalline glass capable of being excited by purple light as well as a preparation method and application of the blue-light microcrystalline glass, and belongs to the technical field of fluorescent materials. The general chemical formula of crystals in the blue-light microcrystalline glass is Li (Sr, Ba) 2Al (PO4) 3: Eu < 2 + >, the crystal structure belongs to a monoclinic system, the space group is P21 / n, the blue-light microcrystalline glass is prepared from the following material components in mole fraction: 10-60 mol% of Li2CO3, 20-50 mol% of SrCO3, 0-50 mol% of BaCO3, 5-30 mol% of Al2O3, 20-60 mol% of P2O5, 0.005-10 mol% of Eu2O3 and 5-30 mol% of B2O3, and the total mole ratio of the material components is 100 mol%. The blue-light microcrystalline glass can be applied to preparation of white-light LED devices.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of fluorescent materials, and particularly relates to a blue light glass ceramic that can be excited by violet light, and a preparation method and application thereof. BACKGROUND

[0002] In recent years, with the deepening of the research on the photo-biological effect, the health attribute of the lighting source has become the focus of public attention. Under this background, the concept of healthy lighting has emerged as the times require, and the core goal is to simulate the sunlight environment through spectral regulation technology and to build a light-biological safe lighting system that meets the human circadian rhythm. As an important breakthrough in this field, the full-spectrum LED can accurately reproduce the continuous spectral distribution of sunlight, not only realizing the synchronous improvement of the color rendering index (R a > 97) and color fidelity (R f > 95), but also effectively inhibiting the physiological interference of short-wave blue light (415-455 nm), thereby providing an indoor space with a lighting solution that combines visual comfort and biological safety.

[0003] The current mainstream technical path of full-spectrum LED can be divided into two categories: 1. Blue light excitation multi-color fluorescent powder system. A 450-460 nm blue light chip excites green / red fluorescent powder (such as β-SiAlON:Eu 2+ , KSF:Mn 4+ ), and the sunlight is simulated through spectral superposition. Although this scheme has cost advantages, it has a significant lack of spectral continuity in the 500-580 nm cyan-yellow transition region, which limits the color gamut coverage (R g value) and the intensity of deep red light (> 650 nm) is insufficient, affecting the true restoration of natural light perception; 2. Full-spectrum fluorescent powder system excited by violet light. A 400-410 nm violet light chip excites blue / green / red three-primary color fluorescent powder (such as BaMgAl 10 O 17 :Eu 2 +, Lu3Al5O 12 :Ce 3 +, CaAlSiN3:Eu 2 +), and a continuous spectrum is constructed through triple-photon conversion. Compared with the traditional scheme, this technology has three major breakthrough advantages: (1) Spectral regulation dimension expansion: through fluorescent powder ratio optimization, the key missing bands of 490-510 nm and 580-630 nm can be accurately filled. (2) Blue light hazard index (BLH) is reduced by more than 40%, meeting the highest exemption level standard of EN62471 light biological safety. (3) It can achieve 98% of the sunlight spectral matching degree (380-780 nm), and has excellent visual-physiological synergistic optimization effect in medical, educational and other scenarios.

[0004] However, the current violet light excited blue light fluorescent material generally exists the problems of low luminous efficiency, insufficient violet light excitation efficiency and poor thermal stability. On the one hand, the performance breakthrough of blue light fluorescent material is relatively limited due to the limitation of the current mainstream blue light excitation scheme. On the other hand, the Stokes shift between the blue light fluorescent body and the violet light excitation source is too small (usually < 50 nm), which significantly reduces the excitation energy conversion efficiency. This technical bottleneck makes the development of violet light excited blue light fluorescent material much more difficult than that of green light / red light system, which becomes the key short board restricting the development of full-spectrum LED, and needs to be broken through by new material design and excitation mechanism innovation.

[0005] In addition, the common powder fluorescent material itself is easy to agglomerate and absorb moisture. If it is used with conventional resin, silica gel and other packaging materials, the thermal quenching effect will be intensified. In order to solve these problems, microcrystalline glass, as a new type of inorganic non-metallic material, enters the research field. It has the advantages of glass and ceramic, and has good optical uniformity, which can reduce light scattering; high chemical stability and strong environmental adaptability. Fluorescent microcrystalline glass is prepared by in-situ crystallization, and doping ions are introduced to realize luminescence. It not only retains the advantages of microcrystalline glass, but also can regulate the luminescent properties of fluorescent substances through microcrystallization, such as changing the crystal structure to affect the energy level and luminescent efficiency. Therefore, microcrystalline glass is an effective carrier of fluorescent materials.

[0006] The Chinese patent with publication number CN113897197A and application date October 25, 2021 discloses a kind of high thermal stability blue light emitting fluorescent material and its preparation method and application, its characteristics are using high temperature solid phase method under the action of fluxing agent and dispersion medium, in reducing atmosphere, successfully prepared new type blue light emitting fluorescent material. The fluorescent material has high thermal stability and exhibits negative thermal quenching performance at 80-240℃. However, it should be pointed out that the excitation spectrum of this material is in the ultraviolet region, so it is only suitable for ultraviolet LED white light devices and is not suitable for violet LED chip excitation full-spectrum emitting white light LED devices. The Chinese patent with publication number CN118599535A and application date October 25, 2021 discloses a kind of blue fluorescent glass ceramic and its preparation method and application. The fluorescent glass ceramic is prepared by co-sintering of substrate glass powder and blue fluorescent powder with chemical formula Gd2O3:xBi 3+ The material exhibits broadband blue light emission of 390-600 nm, and the raw materials are simple. However, the preparation method includes three steps of sintering of fluorescent powder, melting of substrate glass, and co-sintering of glass powder and fluorescent powder. The sintering temperature of the fluorescent powder reaches 1400-1500℃. This method is time-consuming and energy-consuming in the preparation process, which limits its practical production and application.

[0007] Wanjun Tang et al. published "Controllable luminescence in Eu2+ doped Li2Sr2Al(PO4)3 phosphor via tuning the Eu 2+ concentration and codoping Ce 3+ ”, the reported fluorescent material Li2Sr2Al(PO4)3 realizes controllable blue light emission through Eu 2+ ,Ce 3+ co-doping. The excitation main peak of the fluorescent material is located at 352 nm, covering the 300-420 nm band, and its emission spectrum fully covers the blue light emission band, which can be adapted to the current commercial violet chip. However, the Li2Sr2Al(PO4)3 material still has a Eu 3+ signal that can be obviously observed, which is not conducive to blue light emission, resulting in reduced luminous intensity, and its synthesis process involves the use of nitrate drugs and Ce2O3 drugs derived from rare earth resources, which has the disadvantages of high cost, environmental unfriendliness, and complex process. In view of this, the Eu 2+ doped Li2Sr2Al(PO4)3 fluorescent material is relatively limited in the application of violet light excitation white light LED devices, and needs to be further optimized.

[0008] In summary, in view of the technical bottleneck of the current blue light fluorescent material in the violet light excitation full-spectrum LED lighting, a new type of blue glass-ceramics that can be efficiently excited by violet light is designed, which can avoid the inherent defects of powder fluorescent materials while having high efficient luminescence and excellent physical and chemical stability. It has important reference value and application prospect for the research and preparation of high-performance violet light excitation full-spectrum LED devices. SUMMARY

[0009] To solve the problems in the prior art, the present application provides a blue glass-ceramics that can be excited by violet light and its preparation method and application. The blue glass-ceramics has efficient violet light excitation blue light emission characteristics, and the optical uniformity, high chemical and thermal stability of the glass-ceramics, and excellent mechanical properties of the ceramic.

[0010] The technical scheme of the present application is as follows:

[0011] One of the purposes of the present application is to provide a blue glass-ceramics that can be excited by violet light. The crystal chemical formula of the blue glass-ceramics is Li2(Sr,Ba)2Al(PO4)3:Eu 2+ , and the crystal structure belongs to monoclinic system with space group P21 / n.

[0012] Further, the blue light glass ceramic is prepared from the following material components with the following molar fractions: 10-60 mol% Li2CO3, 20-50 mol% SrCO3, 0-50 mol% BaCO3, 5-30 mol% Al2O3, 20-60 mol% P2O5, 0.005-10 mol% Eu2O3, and 5-30 mol% B2O3, wherein the total molar ratio of the above-mentioned material components is 100 mol%.

[0013] Further, the blue light glass ceramic emits a wavelength of 410-600 nm, with a main peak at 450 nm, and a quantum efficiency of >70%.

[0014] The second object of the present application is to provide a preparation method of a blue light glass ceramic that can be excited by purple light, comprising the following steps:

[0015] S1, Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3 and B2O3 are respectively weighed according to the set material component composition, and then transferred to a crucible after being fully ground;

[0016] S2, the raw materials in step S1 are heated and melted under a reducing atmosphere to obtain a glass melt, and then cooled to room temperature in a furnace to obtain a precursor glass;

[0017] S3, the precursor glass obtained in step S2 is heat treated under a reducing atmosphere to obtain the blue light glass ceramic Li2(Sr,Ba)2Al(PO4)3:Eu 2+ .

[0018] Further, the crucible in S1 is any one of an alumina crucible, a corundum crucible or a graphite crucible.

[0019] Further, the heating and melting temperature in S2 is 1000-1300℃, and the heating and melting time is 30-240 min.

[0020] Further, the reducing atmosphere is one or a combination of several of H2, CO and carbon powder.

[0021] Further, the heat treatment temperature in S3 is 500-800℃, and the heat treatment time is 120-480 min.

[0022] Further, the heating and melting process in step S2 and the heat treatment process in step S3 are carried out in a tube-type reduction furnace or a box-type muffle furnace.

[0023] The third object of the present application is to provide an application of a blue light glass ceramic that can be excited by purple light in the preparation of a white light LED device or a purple light LED chip.

[0024] Further, the violet LED chip has an emission wavelength of 380-420 nm.

[0025] Compared with the prior art, the present application has the following advantages:

[0026] 1. The present application discloses a new type of blue light glass-ceramics Li2(Sr,Ba)2Al(PO4)3:Eu 2+ , which is a blue light fluorescent material with a new chemical composition. The design ingeniously combines the optical uniformity, high chemical and thermal stability, and excellent mechanical properties of glass-ceramics, fundamentally avoiding the inherent defects of powder fluorescent materials. By precisely controlling the molar ratio of the matrix glass components Li2CO3, SrCO3, BaCO3, Al2O3, P2O3, Eu2O3, and B2O3, as well as the Sr / Ba ratio, the crystal structure is further optimized, significantly improving the Eu 2+ excitation efficiency near 400 nm in the violet region and blue light emission performance, achieving a significant improvement in luminescent performance. The emission peak of this fluorescent material is close to the standard blue light emission peak, providing a new material design path to overcome the difficulty of developing violet-excited blue light materials.

[0027] 2. The blue light glass-ceramics Li2(Sr,Ba)2Al(PO4)3:Eu 2+ designed in the present application exhibits excellent comprehensive performance, with the most significant advantage being its efficient violet-excited blue light emission characteristics: under 400 nm violet excitation, it can produce a wideband blue light emission covering 410-600 nm, with the main peak accurately located at 450 nm, close to the standard blue light, and the quantum efficiency breakthrough is greater than 70%, far superior to the performance of many existing blue light materials under violet excitation. Secondly, this material has excellent thermal stability, with a luminescence intensity decay rate significantly lower than that of traditional commercial blue powder at high temperatures, ensuring the reliability of the device during long-term operation. In addition, glass-ceramics itself has high mechanical strength, excellent physical and chemical stability, and optical uniformity.

[0028] 3. The blue light glass-ceramics described in the present application has significant application value and competitive advantage in the field of violet-excited full-spectrum LED lighting. Its excellent 400 nm excitation efficiency matches the current commercial violet LED chip with an emission wavelength of 380-420 nm, which can efficiently convert violet photons into the required blue light, effectively solving the core problem of insufficient excitation efficiency of violet-excited blue light materials. The 410-600 nm wideband blue light emission provides high-quality blue light foundation for constructing continuous and complete full-spectrum white light, which helps to fill the key waveband and improve the color rendering index R a , color fidelity R f , color gamut coverage R g , and spectral matching degree of the light source.

[0029] 4. The blue light glass ceramic as an inorganic bulk material, high thermal stability and chemical stability solve the problem of thermal quenching and aging of powder fluorescent material in resin / silica gel packaging, significantly prolong the service life of LED device and maintain the light efficiency stable. At the same time, the preparation process of "melting cooling + in-situ crystallization" is simple, the raw material cost is low, compared with the complex process of pre-synthesizing fluorescent powder and co-sintering with glass powder, the energy consumption and production cost are significantly reduced, which is more conducive to realize large-scale production, and provides strong material support for the popularization of high-performance, health and safety of purple light excited full spectrum LED device. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by purple light prepared by the embodiment 1 of the present application 2+ X-ray diffraction pattern of blue light glass ceramic;

[0031] Figure 2 A Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by purple light prepared by the embodiment 1 of the present application 2+ Scanning electron microscope micro-morphology diagram of blue light glass ceramic;

[0032] Figure 3 A Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by purple light prepared by the embodiment 1 of the present application 2+ Blue light glass ceramic and BaMgAl 10 O 17 :Eu 2+ Excitation spectrum and emission spectrum of commercial blue powder;

[0033] Figure 4 A Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by purple light prepared by the embodiment 1 of the present application 2+ Excitation spectrum of blue light glass ceramic and emission spectrum under different excitation wavelengths;

[0034] Figure 5 A Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by purple light prepared by the embodiments 2-7 of the present application 2+ Emission spectrum of blue light glass ceramic under different Sr / Ba ratios;

[0035] Figure 6 A Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by purple light prepared by the embodiment 10 of the present application 2+ Blue light glass ceramic and BaMgAl 10 O 17:Eu 2+ Temperature dependent emission performance chart of commercial blue powder;

[0036] Figure 7 A Li2(Sr,Ba)2Al(PO4)3:Eu which can be excited by violet light prepared for example 11 of the present application 2+ Quantum efficiency test data chart of blue light glass under 400nm violet light excitation. DETAILED DESCRIPTION

[0037] The present application is further described in the following examples in conjunction with the preferred embodiments. The endpoints of the ranges set forth in the disclosure are presented as approximations because the exact values are subject to variation. The endpoints of the ranges and any values between the endpoints are included in the range. Whenever a numerical range is indicated, it is meant to include all cited values within the indicated range, as well as the range itself. For example, a range from 1 to 10 is intended to include all whole numbers, fractions, and sub-fractions between 1 and 10, as well as the values 1 and 10 themselves. Any numerical values given herein are understood to be approximations, unless indicated otherwise. It is also understood that the endpoints of the ranges are not significant and are presented merely to narrow the range intervening between the stated ranges. It is specifically contemplated that the ranges include the endpoints.

[0038] The experimental methods in the following examples are routine methods, which are carried out according to the techniques or conditions described in the literature in the art or according to the product instructions, unless otherwise specified.

[0039] The materials, reagents and the like used in the following examples can be obtained commercially, unless otherwise specified.

[0040] Example 1

[0041] The present example provides a Li2(Sr,Ba)2Al(PO4)3:Eu which can be excited by violet light 2+ The blue light glass, the preparation method thereof comprises the following steps:

[0042] S1, weigh raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3, B2O3, grind each raw material for 1h, then transfer to an alumina crucible, the amount of each component is as follows: 15mol% Li2CO3, 30mol% SrCO3, 10mol% BaCO3, 10mol% Al2O3, 30mol% P2O5, 1mol% Eu2O3, 4mol% B2O3;

[0043] S2, place the raw materials described in step S1 in a tube furnace, heat and melt at 1000℃ for 240min under H2 reducing atmosphere to obtain a glass melt, and then cool to room temperature with the furnace to obtain a precursor glass;

[0044] S3, the precursor glass obtained in step S2 is placed in a tube furnace, and heat-treated at 600 DEG C for 480 min in a H2 reducing atmosphere to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ Blue light glass-ceramics.

[0045] Examples 2-7

[0046] The examples provide Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by violet light with different Sr / Ba ratios 2+ A method for preparing blue light glass-ceramics, comprising the following steps:

[0047] S1, the raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3, B2O3 are weighed, and each raw material is ground for 1 h before being transferred to an alumina crucible. The amounts of each component are as follows: 15 mol% Li2CO3, (40-z) mol% SrCO3, z mol% BaCO3, 10 mol% Al2O3, 30 mol% P2O5, 1 mol% Eu2O3, 4 mol% B2O3, wherein z = 0, 2, 6, 10, 14, 18;

[0048] S2, the raw materials in step S1 are placed in a tube furnace, and melted at 1000 DEG C for 240 min in a H2 reducing atmosphere to obtain a glass melt, which is then cooled to room temperature in the furnace to obtain a precursor glass;

[0049] S3, the precursor glass obtained in step S2 is placed in a tube furnace, and heat-treated at 600 DEG C for 480 min in a H2 reducing atmosphere to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ Blue light glass-ceramics.

[0050] Example 8

[0051] The examples provide Li2(Sr,Ba)2Al(PO4)3:Eu that can be excited by violet light 2+ A method for preparing blue light glass-ceramics, comprising the following steps:

[0052] S1, the raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3, B2O3 are weighed, and each raw material is ground for 1 h before being transferred to an alumina crucible. The amounts of each component are as follows: 15 mol% Li2CO3, (40-z) mol% SrCO3, z mol% BaCO3, 10 mol% Al2O3, 30 mol% P2O5, 1 mol% Eu2O3, 4 mol% B2O3, wherein z = 0, 2, 6, 10, 14, 18;

[0053] S2, the raw materials described in step S1 are placed in a tube furnace, heated to melt at 1100 DEG C for 180 min under CO reducing atmosphere to obtain a glass melt, and then cooled to room temperature in the furnace to obtain a precursor glass;

[0054] S3, the precursor glass obtained in step S2 is placed in a tube furnace, heat treated at 500 DEG C for 360 min under CO reducing atmosphere to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ Blue light glass-ceramics.

[0055] Example 9

[0056] The embodiment provides a Li2(Sr,Ba)2Al(PO4)3:Eu 2+ A preparation method of blue light glass-ceramics, comprising the following steps:

[0057] S1, raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3 and B2O3 are weighed, and after being ground for 1 h, the raw materials are transferred into a graphite crucible, and the use amounts of the components are as follows: 15 mol% Li2CO3, 30 mol% SrCO3, 10 mol% BaCO3, 10 mol% Al2O3, 30 mol% P2O5, 1 mol% Eu2O3 and 4 mol% B2O3;

[0058] S2, the raw materials described in step S1 are placed in a tube furnace, heated to melt at 1150 DEG C for 120 min under a reducing atmosphere provided by carbon powder to obtain a glass melt, and then cooled to room temperature in the furnace to obtain a precursor glass;

[0059] S3, the precursor glass obtained in step S2 is placed in a tube furnace, heat treated at 550 DEG C for 240 min under a reducing atmosphere provided by carbon powder to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ Blue light glass-ceramics.

[0060] Example 10

[0061] The embodiment provides a Li2(Sr,Ba)2Al(PO4)3:Eu 2+ A preparation method of blue light glass-ceramics, comprising the following steps:

[0062] S1, weigh raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3, B2O3, grind each raw material for 1h, then transfer to a graphite crucible, and the use amounts of each component are as follows: 15mol% Li2CO3, 30mol% SrCO3, 10mol% BaCO3, 10mol% Al2O3, 30mol% P2O5, 1mol% Eu2O3, and 4mol% B2O3;

[0063] S2, place the raw materials in step S1 in a tube furnace, heat and melt at 1200 DEG C for 80min under H2reducing atmosphere to obtain a glass melt, and then cool to room temperature to obtain a precursor glass;

[0064] S3, place the precursor glass obtained in step S2 in a tube furnace, heat treat at 700 DEG C for 180min under H2reducing atmosphere to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ blue light glass-ceramics.

[0065] Example 11

[0066] The embodiment provides a Li2(Sr,Ba)2Al(PO4)3:Eu 2+ A preparation method of blue light glass-ceramics, comprising the following steps:

[0067] S1, weigh raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3, B2O3, grind each raw material for 1h, then transfer to an alumina crucible, and the use amounts of each component are as follows: 15mol% Li2CO3, 30mol% SrCO3, 10mol% BaCO3, 10mol% Al2O3, 30mol% P2O5, 1mol% Eu2O3, and 4mol% B2O3;

[0068] S2, place the raw materials in step S1 in a tube furnace, heat and melt at 1250 DEG C for 60min under H2reducing atmosphere to obtain a glass melt, and then cool to room temperature to obtain a precursor glass;

[0069] S3, place the precursor glass obtained in step S2 in a tube furnace, heat treat at 750 DEG C for 120min under H2reducing atmosphere to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ blue light glass-ceramics.

[0070] Example 12

[0071] The embodiment provides a Li2(Sr,Ba)2Al(PO4)3:Eu 2+A method for preparing a blue light microcrystalline glass, comprising the following steps:

[0072] S1, raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3, B2O3 are weighed, each raw material is ground for 1 h, and then transferred to an alumina crucible, and the use amounts of each component are as follows: 15 mol% Li2CO3, 30 mol% SrCO3, 10 mol% BaCO3, 10 mol% Al2O3, 30 mol% P2O5, 1 mol% Eu2O3, and 4 mol% B2O3;

[0073] S2, the raw materials in step S1 are placed in a tube reduction furnace, heated and melted at 1300 DEG C for 30 min under H2 reducing atmosphere to obtain a glass melt, and then cooled to room temperature to obtain a precursor glass;

[0074] S3, the precursor glass obtained in step S2 is placed in a tube reduction furnace, and heat treated at 780 DEG C for 120 min under H2 reducing atmosphere to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ A blue light microcrystalline glass.

[0075] Example 13

[0076] The embodiment provides a Li2(Sr,Ba)2Al(PO4)3:Eu 2+ A method for preparing a blue light microcrystalline glass, comprising the following steps:

[0077] S1, raw materials Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3, B2O3 are weighed, each raw material is ground for 1 h, and then transferred to an alumina crucible, and the use amounts of each component are as follows: 15 mol% Li2CO3, 30 mol% SrCO3, 10 mol% BaCO3, 10 mol% Al2O3, 30 mol% P2O5, 1 mol% Eu2O3, and 4 mol% B2O3;

[0078] S2, the raw materials in step S1 are placed in a tube reduction furnace, heated and melted at 1300 DEG C for 30 min under H2 reducing atmosphere to obtain a glass melt, and then cooled to room temperature to obtain a precursor glass;

[0079] S3, the precursor glass obtained in step S2 is placed in a tube reduction furnace, and heat treated at 780 DEG C for 120 min under H2 reducing atmosphere to obtain the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ A blue light microcrystalline glass.

[0080] Performance characterization

[0081] 1. Li2(Sr,Ba)2Al(PO4)3:Eu 2+ Glass-ceramic characterization

[0082] Figure 1 Li2(Sr,Ba)2Al(PO4)3:Eu prepared for Example 1 2+ X-ray diffraction pattern of the glass-ceramic, as shown in Figure 1 X-ray diffraction data of the glass-ceramic prepared according to the above method are consistent with the standard card information, indicating that Li2(Sr,Ba)2Al(PO4)3:Eu 2+ crystals are successfully precipitated.

[0083] Figure 2 Li2(Sr,Ba)2Al(PO4)3:Eu prepared for Example 1 2+ Scanning electron microscope micro-morphology of the glass-ceramic, as shown in Figure 2 It can be seen that Li2(Sr,Ba)2Al(PO4)3:Eu 2+ crystals exhibit regular columnar morphology.

[0084] Figure 3 Li2(Sr,Ba)2Al(PO4)3:Eu prepared for Example 1 2+ glass-ceramic and BaMgAl 10 O 17 :Eu 2+ Excitation spectrum and emission spectrum of the commercial blue powder, as shown in Figure 3 Li2(Sr,Ba)2Al(PO4)3:Eu prepared for Example 1 2+ glass-ceramic is significantly better than that of BaMgAl 10 O 17 :Eu 2+ commercial blue powder in the violet light region.

[0085] Figure 4 Li2(Sr,Ba)2Al(PO4)3:Eu prepared for Example 1 2+ Excitation spectrum and emission spectrum under different excitation wavelengths of the glass-ceramic, as shown in Figure 4 Li2(Sr,Ba)2Al(PO4)3:Eu 2+ The strongest peak of the excitation spectrum of the glass-ceramic is near 400 nm, and the emission peak intensity reaches the highest under 400 nm excitation, indicating that it can be effectively excited by a violet light chip, and has high matching degree with a commercial violet light chip.

[0086] 2. Li2(Sr,Ba)2Al(PO4)3:Eu with different Sr / Ba ratios 2+Glass-ceramic characterization

[0087] Figure 5 Li2(Sr,Ba)2Al(PO4)3:Eu prepared in Example 2-7 2+ Emission spectra of glass-ceramics at different Sr / Ba ratios, such as Figure 5 As shown in the figure, under the excitation of a 400nm violet light source, the emission spectrum of the glass-ceramics covers a broadband range of 410 to 600nm, with a peak at 450nm, which is close to the standard blue light emission peak.

[0088] 3. Thermal stability characterization

[0089] Figure 6 The Li2(Sr,Ba)2Al(PO4)3:Eu prepared by coupling the 410nm purple light chip in Example 10 2+ Glass-ceramics and BaMgAl 10 O 17 :Eu 2+ Temperature dependence of emission performance of commercial blue powder, such as Figure 6 As shown, Li2(Sr,Ba)2Al(PO4)3:Eu 2+ Glass-ceramics exhibits better performance than BaMgAl 10 O 17 :Eu 2+ Commercial blue powder has higher thermal stability.

[0090] 4. Quantum efficiency characterization

[0091] Figure 7 Li2(Sr,Ba)2Al(PO4)3:Eu prepared in Example 11 2+ The quantum efficiency test data of micro-ceramic glass under 400nm violet light excitation is shown in the figure. Figure 7 As shown, using the fluorescence spectrometer FLS1000 and integrating sphere accessories, with barium sulfate as a white plate, under 400nm violet light excitation, the Li2(Sr,Ba)2Al(PO4)3:Eu 2+ The quantum efficiency of the glass-ceramic is >70%, indicating that the material can be used in violet light-excited full-spectrum lighting LED devices.

[0092] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A blue light-emitting glass-ceramic that can be excited by violet light, characterized in that: The crystal chemical formula of the blue light microcrystalline glass is Li2(Sr,Ba)2Al(PO4)3:Eu 2+ The crystal structure belongs to the monoclinic system and the space group is P21 / n.

2. The blue light-emitting glass-ceramic capable of being excited by violet light according to claim 2, characterized in that: The blue light microcrystalline glass is prepared from the following material components in molar fractions: 10-60 mol% Li2CO3, 20-50 mol% SrCO3, 0-50 mol% BaCO3, 5-30 mol% Al2O3, 20-60 mol% P2O5, 0.005-10 mol% Eu2O3, 5-30 mol% B2O3, and the total molar ratio of the above material components is 100 mol%.

3. The blue light-emitting glass-ceramic capable of being excited by violet light according to claim 2, characterized in that: Under the excitation of 400nm violet light, the blue light micro-ceramic glass has an emission wavelength of 410-600nm, a main peak at 450nm, and a quantum efficiency greater than 70%.

4. A method for preparing blue light-emitting glass-ceramics that can be excited by violet light according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1. Weigh Li2CO3, SrCO3, BaCO3, Al2O3, P2O5, Eu2O3 and B2O3 according to the set material components, grind them thoroughly and transfer them to a crucible; S2, heating and melting the raw materials in step S1 under a reducing atmosphere to obtain a glass melt, and then cooling it to room temperature in the furnace to obtain a precursor glass; S3, heat-treating the precursor glass obtained in step S2 under a reducing atmosphere to obtain the blue light micro-ceramic glass Li2(Sr,Ba)2Al(PO4)3:Eu 2+ .

5. The method for preparing a blue-light glass-ceramic that can be excited by violet light according to claim 4, characterized in that: The crucible in S1 is any one of an alumina crucible, a corundum crucible or a graphite crucible.

6. The method for preparing a blue-light glass-ceramic that can be excited by violet light according to claim 4, characterized in that: The heating and melting temperature in S2 is 1000-1300° C., and the heating and melting time is 30-240 min.

7. The method for preparing a blue-light glass-ceramic that can be excited by violet light according to claim 4, characterized in that: The reducing atmosphere is one or a combination of H2, CO, and carbon powder.

8. The method for preparing a blue-light glass-ceramic that can be excited by violet light according to claim 4, characterized in that: The heat treatment temperature in S3 is 500-800° C., and the heat treatment time is 120-480 min.

9. The method for preparing a blue-light glass-ceramic that can be excited by violet light according to claim 4, characterized in that: The heating and melting process in step S2 and the heat treatment process in step S3 are carried out in a tubular reduction furnace or a box-type muffle furnace.

10. Application of the blue light-emitting glass-ceramics that can be excited by violet light according to any one of claims 1 to 3 in a white light LED device.

Images