Luminescent glass and preparation method thereof

Abstract

The invention relates to the technical field of hybrid glass, and discloses luminescent glass and a preparation method thereof. The luminescent glass is prepared from the following raw materials: organic ion salt and metal halide, the metal ions in the metal halide comprise at least one of Pb, Cu, Ag, Cr, Mn, Sm, Eu or Yb ions. The luminescent glass provided by the invention is photoluminescence organic-inorganic hybrid glass taking metal halide as an inorganic component, metal ions form a luminescence center, fluorescent light with colors of bright red, green, blue and the like can be generated under the excitation of ultraviolet light, the stability of luminescence characteristics is good, the peak shape is not influenced by the frequency and power change of an excitation light source, and the luminescent glass can be applied to the field of photoluminescence. The influence of freezing treatment or multi-time melting-cooling treatment is avoided; the material has relatively strong absorption in an ultraviolet region, has relatively weak absorption on visible light and infrared light, and has the potential of ultraviolet light detection; the method can be applied to the fields of display, illumination, optical decoration, anti-counterfeiting, data encryption, ultraviolet light detection and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid glass, and particularly to a luminescent glass and a preparation method thereof. Background Art

[0002] Glass materials are usually divided into two categories: organic glass and inorganic glass. In recent years, hybrid glass materials composed of inorganic components and organic components assembled synergistically at the molecular level have attracted great attention due to their diverse structures and comprehensive functions.

[0003] Among these novel hybrid glasses, organic-metal halide glasses have a simple preparation process and are easy to process and form. They not only inherit the high transparency and mechanical strength of traditional glasses but also possess the characteristics of crystal materials, such as rich phase transition behaviors and chemical structure stability. Therefore, they have good light response ability and light stability, and excellent optical properties.

[0004] Rare earth elements refer to the lanthanide elements with atomic numbers 57 - 71 in the periodic table, as well as yttrium (Y) and scandium (Sc), which have [Xe]4f 0-14 5d 0-16 s 2 and [Xe]4f 0-14 6s 2 electronic configurations. The luminescence of rare earth ions mainly comes from the f-f transitions of 4f electrons and the 4f-5d transitions of 4f electrons and 5d electrons. Rare earth ions usually form luminescence centers in the form of +3 valence. Since the number of 4f orbital electrons in different rare earth ions is different, their electron transitions and energy level transitions are different, which provides a rich selection and adjustment space for the preparation of luminescent glasses. Based on these characteristics, luminescent glasses prepared using rare earth elements show great application potential in optoelectronic high-tech fields such as lasers, optical amplifiers, optical communications, energy storage, and displays.

[0005] However, how to select suitable organic and inorganic components, how to precisely control the crystal-amorphous transformation of materials, and how to optimize the luminescence performance by adjusting factors such as excitation conditions are still difficult problems to be solved in the development of organic-metal halide glasses doped with rare earth elements. Summary of the Invention

[0006] The present invention aims to solve at least one of the above technical problems existing in the prior art. To this end, one object of the present invention is to provide a luminescent glass.

[0007] Another object of the present invention is to provide a preparation method of this luminescent glass.

[0008] A third object of the present invention is to provide an application of this luminescent glass.

[0009] A fourth object of the present invention is to provide an ultraviolet light detector.

[0010] To achieve the above object, the technical solution adopted by the present invention is:

[0011] A first aspect of the present invention provides a luminescent glass prepared from raw materials including: organic ion salts and metal halides; the metal ions in the metal halides include at least one of Pb, Cu, Ag, Cr, Mn, Sm, Eu or Yb ions.

[0012] In some embodiments of the present invention, the molar ratio of the organic ion salt to the metal halide is (1-4):1.

[0013] In some specific embodiments of the present invention, the molar ratio of the organic ion salt to the metal halide is (1-3):1.

[0014] In some embodiments of the present invention, the organic ion salt is selected from at least one of (methoxymethyl) triphenylphosphonium chloride, allyl triphenylphosphonium bromide, and ethoxycarbonylmethyl triphenylphosphonium bromide.

[0015] In some specific embodiments of the present invention, the organic ion salt is (methoxymethyl) triphenylphosphonium chloride (P-Cl).

[0016] In some embodiments of the present invention, the halogen ions in the metal halide include Cl - , Br - or I - at least one of.

[0017] In some specific embodiments of the present invention, the metal halide is selected from one of lead bromide (PbBr2), cuprous chloride (CuCl), silver bromide (AgBr), chromium chloride (CrCl3), manganese chloride (MnCl2), samarium chloride (SmCl3), europium chloride (EuCl2), europium chloride hexahydrate (EuCl3·6H2O), or ytterbium chloride hexahydrate (YbCl3·6H2O).

[0018] In some embodiments of the present invention, the luminescent glass includes lead-based luminescent glass, copper-based luminescent glass, silver-based luminescent glass, chromium-based luminescent glass, manganese-based luminescent glass, samarium-based luminescent glass, europium-based luminescent glass, ytterbium-based luminescent glass.

[0019] In some embodiments of the present invention, the luminescent glass is colorless, white, yellow or green transparent under natural light.

[0020] In some embodiments of the present invention, the excitation wavelength of the luminescent glass is 343-405nm.

[0021] In some embodiments of the present invention, the emission wavelength of the luminescent glass is 505 - 705 nm.

[0022] In some specific embodiments of the present invention, the lead-based luminescent glass emits blue-green fluorescence at 528 nm.

[0023] In some specific embodiments of the present invention, the copper-based luminescent glass emits light yellow fluorescence at 585 nm.

[0024] In some specific embodiments of the present invention, the chromium-based luminescent glass emits blue fluorescence at 505 nm.

[0025] In some specific embodiments of the present invention, the manganese-based luminescent glass emits green fluorescence at 536 nm.

[0026] In some specific embodiments of the present invention, the samarium-based luminescent glass emits light blue fluorescence at 509 nm.

[0027] In some specific embodiments of the present invention, the europium-based luminescent glass emits red fluorescence at 612 nm.

[0028] In some specific embodiments of the present invention, the ytterbium-based luminescent glass emits light blue fluorescence at 509 nm.

[0029] In some specific embodiments of the present invention, the silver-based luminescent glass emits blue fluorescence at 506 nm.

[0030] In some embodiments of the present invention, the average fluorescence lifetime of the luminescent glass at room temperature is 5 - 7 ns.

[0031] In some embodiments of the present invention, the average fluorescence lifetime of the luminescent glass at - 18 °C is 4 - 6 ns.

[0032] In some embodiments of the present invention, the band gap of the luminescent glass is 3 - 5 eV.

[0033] The second aspect of the present invention provides a preparation method of the luminescent glass described in the first aspect of the present invention, including the following steps:

[0034] Mix the organic ionic salt and metal halide, heat and melt them, and then quench and cool to obtain the luminescent glass.

[0035] In some embodiments of the present invention, the temperature of the heating and melting is 170 - 200 °C, and the time is 30 - 60 min.

[0036] In some specific embodiments of the present invention, the temperature of the heating and melting is 170 - 185 °C, and the time is 30 - 45 min.

[0037] In some embodiments of the present invention, the specific operation of heating and melting is as follows: preheat the oven to 170 - 200 °C at a heating rate of 180 - 200 °C / h, put in the mixture of organic ionic salt and metal halide, and keep it molten for 30 - 60 min.

[0038] In some specific embodiments of the present invention, the specific operation of heating and melting is as follows: preheat the oven to 170 - 185 °C at a heating rate of 180 - 200 °C / h, put in the mixture of organic ionic salt and metal halide, and keep it molten for 30 - 45 min.

[0039] In some embodiments of the present invention, the temperature of quenching and cooling is 15 - 25 °C.

[0040] In some specific embodiments of the present invention, the temperature of quenching and cooling is 20 - 25 °C.

[0041] In some embodiments of the present invention, the time of quenching and cooling is 3 - 10 min.

[0042] In some specific embodiments of the present invention, the time of quenching and cooling is 3 - 5 min.

[0043] In some embodiments of the present invention, after mixing the organic ionic salt and the metal halide, it further includes the step of grinding and pulverizing the organic ionic salt and the metal halide.

[0044] In the present invention, the luminescent glass is prepared by the melt quenching method. After mixing the organic ionic salt and the metal halide, it is heated and melted to a transparent state to form a uniform glass liquid, and then rapidly quenched and cooled at room temperature. After the glass liquid solidifies, the glassy luminescent glass can be formed.

[0045] The third aspect of the present invention provides the application of the luminescent glass described in the first aspect of the present invention in display, lighting, optical decoration, anti-counterfeiting, data encryption, and ultraviolet light detection.

[0046] The fourth aspect of the present invention provides an ultraviolet light detector, which includes the luminescent glass described in the first aspect of the present invention.

[0047] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0048] 1) The luminescent glass provided by the present invention is a photoluminescent organic-inorganic hybrid glass with metal Pb, Cu, Ag, Cr, Mn, Sm, Eu or Yb halides as inorganic components. Based on the luminescent centers formed by metal ions, it can generate fluorescence in colors such as bright red, green, and blue under ultraviolet light excitation. Moreover, the peak shape of the emission peak is not affected by the changes in the frequency and power of the excitation light source, nor by freeze treatment or multiple melting-cooling treatments, and the luminescent characteristics have good stability;

[0049] 2) The preparation method of the luminescent glass provided by the present invention uses the melt quenching method to prepare the hybrid glass. The steps are simple, and it can be rapidly quenched and cooled at room temperature, enabling easy control of the glass crystalline-amorphous transformation, which is suitable for industrial application;

[0050] 3) The luminescent glass provided by the present invention has strong absorption in the ultraviolet region and weak absorption in the visible light and infrared light regions. It has the potential for use in ultraviolet detection, can be used for the development of ultraviolet detectors, and is used in fields such as environmental monitoring and medical detection to monitor air pollutants, detect ultraviolet damage, etc.;

[0051] 4) The luminescent glass provided by the present invention has good optical characteristic stability, and the fluorescence lifetime is in the nanosecond level. It has the ability to rapidly respond to ultraviolet light and provide clear signals, and can be applied to fields such as display, lighting, optical decoration, anti-counterfeiting, data encryption, and ultraviolet detection. Description of the Drawings

[0052] Figure 1 It is a comparison diagram of the europium-based luminescent glass in Example 1 under natural light and ultraviolet lamp irradiation;

[0053] Figure 2 It is a comparison diagram of the lead-based luminescent glass in Example 2 under natural light and ultraviolet lamp irradiation;

[0054] Figure 3 It is a comparison diagram of the copper-based luminescent glass in Example 3 under natural light and ultraviolet lamp irradiation;

[0055] Figure 4 It is a comparison diagram of the chromium-based luminescent glass in Example 4 under natural light and ultraviolet lamp irradiation;

[0056] Figure 5 It is a comparison diagram of the manganese-based luminescent glass in Example 5 under natural light and ultraviolet lamp irradiation;

[0057] Figure 6 It is a comparison diagram of the samarium-based luminescent glass in Example 6 under natural light and ultraviolet lamp irradiation;

[0058] Figure 7 It is a comparison diagram of the ytterbium-based luminescent glass in Example 7 under natural light and ultraviolet lamp irradiation;

[0059] Figure 8 It is a comparison diagram of the silver-based luminescent glass under natural light and ultraviolet lamp irradiation in Example 8;

[0060] Figure 9 It is the emission spectrum of the europium-based luminescent glass in Example 1 under 343 nm ultraviolet excitation light;

[0061] Figure 10 It is the emission spectrum of the europium-based luminescent glass in Example 1 under 405 nm ultraviolet excitation light;

[0062] Figure 11 It is the ultraviolet-visible-infrared absorption spectrum of the europium-based luminescent glass in Example 1;

[0063] Figure 12 It is the Tauc equation curve of the europium-based luminescent glass in Example 1;

[0064] Figure 13 It is the fluorescence spectrum diagram of the europium-based luminescent glass in Example 1 after low-temperature treatment;

[0065] Figure 14 It is the fluorescence lifetime fitting curve of the europium-based luminescent glass in Example 1 before low-temperature treatment;

[0066] Figure 15 It is the fluorescence lifetime fitting curve of the europium-based luminescent glass in Example 1 after low-temperature treatment;

[0067] Figure 16 It is the fluorescence spectrum diagram of the europium-based luminescent glass in Example 1 after multiple melting-cooling treatments. Specific implementation manners

[0068] The content of the present invention will be further described in detail through specific examples below. The raw materials, reagents or devices used in the examples can be obtained from conventional commercial channels or can be obtained by existing technical methods without special instructions. Unless otherwise specified, the test or measurement methods are all conventional methods in the art.

[0069] Example 1

[0070] In this example, a europium-based luminescent glass is prepared, and the steps are as follows:

[0071] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and europium chloride hexahydrate according to a molar ratio of 2:1, and uniformly grind them in a mortar to fully mix and obtain a mixed powder;

[0072] S2. Preheat the oven to 170 °C at a heating rate of 200 °C / h, place the mixed powder in an open glass bottle and then put it into the preheated oven, keep it warm and molten for 30 min to form a yellow transparent glass liquid;

[0073] S3. Place the glass liquid at room temperature and cool it by natural quenching. After 3 minutes, it solidifies to form homogeneous europium-based luminescent glass.

[0074] Example 2

[0075] In this example, a lead-based luminescent glass is prepared as follows:

[0076] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and lead bromide in a molar ratio of 2.5:1, and grind them evenly in a mortar to obtain a well-mixed powder.

[0077] S2. Preheat the oven to 180 °C at a heating rate of 180 °C / h. Place the mixed powder in an open glass bottle and then put it into the preheated oven. Keep it melted for 35 minutes to form a molten glass liquid.

[0078] S3. Place the glass liquid at room temperature and cool it by natural quenching. After 5 minutes, it solidifies to form homogeneous lead-based luminescent glass.

[0079] Example 3

[0080] In this example, a copper-based luminescent glass is prepared as follows:

[0081] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and cuprous chloride in a molar ratio of 2:1, and grind them evenly in a mortar to obtain a well-mixed powder.

[0082] S2. Place the mixed powder in an open glass bottle and put it into an oven preheated to 185 °C. Heat and melt it at a heating rate of 190 °C / h for 30 minutes to form a molten glass liquid.

[0083] S3. Place the glass liquid at room temperature and cool it by natural quenching. After 3 minutes, it solidifies to form homogeneous copper-based luminescent glass.

[0084] Example 4

[0085] In this example, a chromium-based luminescent glass is prepared as follows:

[0086] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and chromium chloride in a molar ratio of 3:1, and grind them evenly in a mortar to obtain a well-mixed powder.

[0087] S2. Preheat the oven to 170 °C at a heating rate of 180 °C / h. Place the mixed powder in an open glass bottle and then put it into the preheated oven. Keep it melted for 45 minutes to form a molten glass liquid.

[0088] S3. Place the glass liquid at room temperature and cool it by natural quenching. After 4 minutes, it solidifies to form homogeneous chromium-based luminescent glass.

[0089] Example 5

[0090] In this example, a manganese-based luminescent glass was prepared as follows:

[0091] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and manganese chloride in a molar ratio of 3:1, and grind them evenly in a mortar and mix them thoroughly to obtain a mixed powder;

[0092] S2. Preheat the oven to 175 °C at a heating rate of 185 °C / h. Place the mixed powder in an open glass bottle and then put it into the preheated oven, and keep it molten for 35 min to form a molten glass liquid;

[0093] S3. Place the glass liquid at room temperature and cool it by natural quenching. After 3 min, it solidifies to form a homogeneous manganese-based luminescent glass.

[0094] Example 6

[0095] In this example, a samarium-based luminescent glass was prepared as follows:

[0096] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and samarium chloride in a molar ratio of 2:1, and grind them evenly in a mortar and mix them thoroughly to obtain a mixed powder;

[0097] S2. Preheat the oven to 175 °C at a heating rate of 190 °C / h. Place the mixed powder in an open glass bottle and then put it into the preheated oven, and keep it molten for 30 min to form a molten glass liquid;

[0098] S3. Place the glass liquid at room temperature and cool it by natural quenching. After 5 min, it solidifies to form a homogeneous samarium-based luminescent glass.

[0099] Example 7

[0100] In this example, a ytterbium-based luminescent glass was prepared as follows:

[0101] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and ytterbium chloride hexahydrate in a molar ratio of 2:1, and grind them evenly in a mortar and mix them thoroughly to obtain a mixed powder;

[0102] S2. Preheat the oven to 170 °C at a heating rate of 200 °C / h. Place the mixed powder in an open glass bottle and then put it into the preheated oven, and keep it molten for 35 min to form a molten glass liquid;

[0103] S3. Place the glass liquid at room temperature and cool it by natural quenching. After 4 min, it solidifies to form a homogeneous ytterbium-based luminescent glass.

[0104] Example 8

[0105] In this embodiment, a silver-based luminescent glass is prepared as follows:

[0106] S1. Weigh (methoxymethyl) triphenylphosphonium chloride and silver bromide according to a molar ratio of 2.5:1, and grind them evenly in a mortar to obtain a well-mixed powder;

[0107] S2. Preheat the oven to 180°C at a heating rate of 190°C / h. Place the mixed powder in an open glass bottle and then put it into the preheated oven. Keep it melted for 35 minutes to form a molten glass liquid;

[0108] S3. Place the glass liquid at room temperature and let it cool by natural quenching. After 3 minutes, it solidifies to form a homogeneous silver-based luminescent glass.

[0109] Performance testing

[0110] 1. Respectively irradiate the luminescent glasses prepared in Examples 1-8 with natural light and an ultraviolet lamp, and observe their surface morphology and fluorescence color:

[0111] Figure 1 Figure for comparing the europium-based luminescent glass in Example 1 under natural light and ultraviolet lamp irradiation. As can be seen from Figure 1 it, the europium-based luminescent glass prepared in Example 1 is yellow and transparent under natural light, and fine cracks can be seen inside. After being irradiated with a 365nm ultraviolet lamp, the europium-based luminescent glass shows bright red fluorescence.

[0112] Figure 2 Figure for comparing the lead-based luminescent glass in Example 2 under natural light and ultraviolet lamp irradiation. As can be seen from Figure 2 it, the lead-based luminescent glass prepared in Example 2 is colorless and transparent under natural light. After being irradiated with a 365nm ultraviolet lamp, the lead-based luminescent glass shows bright blue-green fluorescence.

[0113] Figure 3 Figure for comparing the copper-based luminescent glass in Example 3 under natural light and ultraviolet lamp irradiation. As can be seen from Figure 3 it, the copper-based luminescent glass prepared in Example 3 is light yellow and transparent under natural light. After being irradiated with a 365nm ultraviolet lamp, the copper-based luminescent glass shows light yellow fluorescence.

[0114] Figure 4 Figure for comparing the chromium-based luminescent glass in Example 4 under natural light and ultraviolet lamp irradiation. As can be seen from Figure 4 it, the chromium-based luminescent glass prepared in Example 4 is colorless and transparent under natural light. After being irradiated with a 365nm ultraviolet lamp, the chromium-based luminescent glass shows bright blue fluorescence.

[0115] Figure 5It is a comparison diagram of the manganese-based luminescent glass in Example 5 under natural light and ultraviolet lamp irradiation. It can be seen from Figure 5 that the manganese-based luminescent glass prepared in Example 5 is light green and transparent under natural light. After being irradiated with a 365 nm ultraviolet lamp, the manganese-based luminescent glass exhibits bright green fluorescence.

[0116] Figure 6 It is a comparison diagram of the samarium-based luminescent glass in Example 6 under natural light and ultraviolet lamp irradiation. It can be seen from Figure 6 that the samarium-based luminescent glass prepared in Example 6 is light yellow and transparent under natural light. After being irradiated with a 365 nm ultraviolet lamp, the samarium-based luminescent glass exhibits light blue fluorescence.

[0117] Figure 7 It is a comparison diagram of the ytterbium-based luminescent glass in Example 7 under natural light and ultraviolet lamp irradiation. It can be seen from Figure 7 that the ytterbium-based luminescent glass prepared in Example 7 is white and transparent under natural light. After being irradiated with a 365 nm ultraviolet lamp, the ytterbium-based luminescent glass exhibits light blue fluorescence.

[0118] Figure 8 It is a comparison diagram of the silver-based luminescent glass in Example 8 under natural light and ultraviolet lamp irradiation. It can be seen from Figure 8 that the silver-based luminescent glass prepared in Example 8 is colorless and transparent under natural light. After being irradiated with a 365 nm ultraviolet lamp, the silver-based luminescent glass exhibits blue fluorescence.

[0119] Table 1 is a summary table of the emission wavelengths and fluorescence colors of the luminescent glasses in Examples 1-8 under 365 nm ultraviolet lamp irradiation. It can be seen from Table 1 that the luminescent glasses in Examples 1-8 all have the characteristics of photoluminescence, and the fluorescence colors are diverse.

[0120] Table 1 Emission wavelengths and fluorescence colors of the luminescent glasses in Examples 1-8 under 365 nm ultraviolet lamp irradiation

[0121] Doped metal element Excitation wavelength Emission wavelength Fluorescent color Example 1 Eu 365nm 612nm Red Example 2 Pb 365nm 528nm Blue-green Example 3 Cu 365nm 585nm Light yellow Example 4 Cr 365nm 505nm Blue Example 5 Mn 365nm 536nm Green Example 6 Sm 365nm 509nm Light blue Example 7 Yb 365nm 509nm Light blue Example 8 Ag 365nm 506nm Blue

[0122] 2. Transfer the glass bottle containing the molten europium-based luminescent glass liquid in Example 1 to a glass slide, and test the emission spectrum of the europium-based luminescent glass under different laser conditions:

[0123] Figure 9 It is the emission spectrum of the europium-based luminescent glass in Example 1 under 343 nm ultraviolet excitation light, Figure 10 It is the emission spectrum of the europium-based luminescent glass in Example 1 under 405 nm ultraviolet excitation light. It can be seen from Figure 9 and Figure 10It can be seen that under 343 nm and 405 nm ultraviolet excitation light, the europium-based luminescent glass in Example 1 has narrow emission peaks at 593 nm, 612 nm, 619 nm, 654 nm and 704 nm, which originate from the 5D0→7FJ (J = 0, 1, 2, 3, 4) electronic transitions of Eu 3+ Among them, the luminescence at 612 nm is the most significant, corresponding to the 5D0→7F2 transition, showing bright red and having the maximum intensity.

[0124] In addition, under 343 nm ultraviolet excitation light, when the power is changed to 5 mW, 10 mW and 15 mW, it is found that the emission peak position and peak shape of the europium-based luminescent glass in Example 1 under 343 nm ultraviolet excitation light are not affected by the power, but as the power increases, the emission peak intensity increases; under 405 nm ultraviolet excitation light, when the frequency is changed to 25 MHz, 50 MHz, 150 MHz and 250 MHz, it is found that the emission peak position and peak shape of the europium-based luminescent glass in Example 1 under 405 nm ultraviolet excitation light are not affected by the frequency, but as the frequency increases, the emission peak intensity increases, indicating that the luminescence performance of the europium-based luminescent glass provided by the present invention is relatively stable, the peak shape is not affected by the changes in the frequency and power of the excitation light source, and the fluorescence intensity can be adjusted by adjusting the frequency or power of the excitation light source to optimize the luminescence performance.

[0125] 3. Measure the ultraviolet-visible-infrared absorption spectrum of the europium-based luminescent glass in Example 1 and calculate its optical band gap:

[0126] Figure 11 is the ultraviolet-visible-infrared absorption spectrum of the europium-based luminescent glass in Example 1. It can be seen from Figure 11 that the europium-based luminescent glass in Example 1 has a relatively high absorbance in the ultraviolet region with a wavelength less than 400 nm. In the visible light region of 400 - 700 nm, the absorbance gradually decreases and there are no obvious absorption peaks. In the infrared region greater than 700 nm, the absorbance continues to slowly decrease and remains at a relatively low level. This indicates that the europium-based luminescent glass in Example 1 has strong absorption in the ultraviolet region and weak absorption in the visible and infrared lights, and has the potential for ultraviolet light detection.

[0127] Use the photon energy formula (Equation I) and the Tauc equation (Equation II) to calculate the optical band gap of the europium-based luminescent glass in Example 1:

[0128] hv = 1240 / λ (Equation I)

[0129] (αhv) 1 / n = B(hv - Eg) (Equation II)

[0130] In the formula, Eg is the band gap width of the semiconductor (eV), λ is the wavelength (nm), α is the optical absorption coefficient, hν is the photon energy, B is the band tailoring factor constant, and the exponent n is directly related to the semiconductor type. Here, n = 1 / 2 is taken for calculation.

[0131] For simplicity of calculation, the absorbance value is used to replace the optical absorption coefficient α, and a function curve of (αhν) 2 versus hν is made. Figure 12 It is the Tauc equation curve of the europium-based luminescent glass in Example 1. When the photon energy hν approaches the band gap Eg, the optical absorption coefficient will increase rapidly. Therefore, the curve of (αhν) 2 versus hν will have an obvious inflection point near hν = Eg. A tangent is made at this inflection point and extended backward to the x-axis. The intersection point of the tangent and the x-axis is the band gap Eg, which is approximately 3.34 eV.

[0132] 4. Place the europium-based luminescent glass in Example 1 in a fume hood and reheat it to 170 °C to achieve secondary melting. Transfer part of the molten glass liquid onto a glass slide and let it cool naturally until it completely solidifies. Place the glass slide with the glass sample in a freezing environment at -18 °C for 2 h. After the freezing is completed, take out the sample and test the fluorescence spectrum and fluorescence lifetime.

[0133] Figure 13 It is the fluorescence spectrum diagram of the europium-based luminescent glass in Example 1 after low-temperature treatment. As can be seen from Figure 13 it, under ultraviolet excitation light of 343 nm and 15 mW, after the europium-based luminescent glass in Example 1 is frozen at -18 °C, its fluorescence spectrum has no significant difference from that before the freezing treatment. There are still narrow emission peaks at 593 nm, 612 nm, 619 nm, 654 nm, and 704 nm, and the luminescence at 612 nm is the most significant. The luminescence intensity and full width at half maximum are similar to those before the freezing treatment, indicating that the luminescence characteristics of the europium-based luminescent glass in Example 1 are relatively stable and will not be damaged by low-temperature freezing treatment.

[0134] Figure 14 It is the fluorescence lifetime fitting curve of the europium-based luminescent glass in Example 1 before low-temperature treatment. Figure 15 It is the fluorescence lifetime fitting curve of the europium-based luminescent glass in Example 1 after low-temperature treatment. As can be seen from Figure 14 and Figure 15 it, before the freezing treatment at -18 °C, the average fluorescence lifetime of the europium-based luminescent glass in Example 1 is 5.46 ns. After the freezing treatment, the average fluorescence lifetime is 4.74 ns, and the difference is small, which verifies again that the low-temperature freezing treatment will not damage the luminescence characteristics of the europium-based luminescent glass in Example 1.

[0135] 5. Place the europium-based luminescent glass in Example 1 in a fume hood and reheat it to 170 °C to achieve secondary melting. Transfer a part of the molten glass liquid onto a glass slide and let it cool naturally until it completely solidifies. Repeat the above operations to perform multiple (≥5 times) melting-cooling treatments on the europium-based luminescent glass. Take the finally cooled sample to test the fluorescence spectrum:

[0136] Figure 16 is the fluorescence spectrum diagram of the europium-based luminescent glass in Example 1 after multiple melting-cooling treatments. It can be seen from Figure 16 that after multiple melting-cooling treatments, the fluorescence spectrum of the europium-based luminescent glass in Example 1 under 343 nm, 15 mW ultraviolet excitation light has no obvious difference from the initial one, and there are still narrow emission peaks at 593 nm, 612 nm, 619 nm, 654 nm and 704 nm, and the luminescence at 612 nm is the most significant. That is, the luminescence characteristics of the europium-based luminescent glass in Example 1 are not affected by multiple melting-cooling treatments, and the luminescence characteristics have high stability.

[0137] The luminescent glass provided by the present invention has stable luminescence characteristics, is not affected by low-temperature freezing treatment and multiple melting-cooling treatments, and has strong adaptability to the environment. During actual application, the luminescence effect will not be significantly affected by environmental changes, and it has obvious advantages in outdoor display and lighting scenarios under complex climate conditions; the peak shape of the emission peak of the luminescent glass is not affected by the frequency and power changes of the excitation light source. By adjusting the frequency or power of the excitation light source, the regulation of fluorescence intensity can be achieved. In the fields of display, lighting, optical decoration, etc., flexible regulation of brightness can be realized. In the field of data encryption, information hiding and display can be achieved by regulating the parameters of the excitation light source; the luminescent glass has strong absorption only in the ultraviolet region and can be used to design anti-counterfeiting labels and markings, providing an intuitive and difficult-to-counterfeit basis for product authenticity identification; the fluorescence characteristics and nanosecond-level fluorescence lifetime of the luminescent glass enable it to have the ability to quickly respond to ultraviolet light and provide clear signals, and can be used to develop efficient ultraviolet detectors to achieve fast and sensitive ultraviolet detection. The detector can convert the red light signal emitted by the glass material by integrating a photodiode or a photosensitive battery, and then realize the quantitative detection of ultraviolet light. This detector can be applied to environmental monitoring, medical detection and other fields to monitor air pollutants and detect ultraviolet damage, etc.

Claims

1. A luminescent glass, characterized in that, Prepared from raw materials including: organic ionic salt and metal halide; the metal ions in the metal halide include at least one of Pb, Cu, Ag, Cr, Mn, Sm, Eu or Yb ions.

2. The luminescent glass according to claim 1, wherein The molar ratio of the organic ionic salt to the metal halide is (1-4):

1.

3. The luminescent glass according to claim 1 or 2, characterized in that, The organic ionic salt is selected from at least one of (methoxymethyl)triphenylphosphonium chloride, allyltriphenylphosphonium bromide, and ethoxycarbonylmethyltriphenylphosphonium bromide.

4. The luminescent glass according to claim 1 or 2, characterized in that, The halogen ions in the metal halide include Cl - , Br - or I - and at least one of them.

5. The preparation method of the luminescent glass according to any one of claims 1-4, characterized in that, Including the following steps: Mix the organic ionic salt and the metal halide, heat and melt, and then quench and cool to obtain the luminescent glass.

6. The preparation method according to claim 5, characterized in that The temperature for heating and melting is 170-200°C, and the time is 30-60 min.

7. The preparation method according to claim 5, characterized in that, The temperature for quenching and cooling is 15-25°C.

8. The preparation method according to claim 7, characterized in that, The time for quenching and cooling is 3-10 min.

9. Application of the luminescent glass according to any one of claims 1-4 in display, lighting, optical decoration, anti-counterfeiting, data encryption, and ultraviolet light detection.

10. An ultraviolet light detector, characterized in that, Including the luminescent glass according to any one of claims 1-4.

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