A self-crystallizing borosilicate glass, its preparation method and application

Abstract

This invention belongs to the field of optical functional materials technology, and discloses a self-crystallizing borosilicate glass, its preparation method, and its applications. The glass comprises a borosilicate glass matrix and perovskite nanocrystals uniformly dispersed within the glass matrix. By precisely controlling the glass composition and preparation process, this invention enables the perovskite nanocrystals to self-crystallize in situ within the borosilicate glass matrix. The emission peak center of the product is located at 488 nm (the core wavelength band with low light attenuation in water), and the full width at half maximum (FWHM) of the emission peak is approximately 30 nm. It possesses core advantages such as high photoluminescence quantum yield (54.5%), excellent power stability, and short fluorescence lifetime (6.71~9.67 ns). The obtained glass sample exhibits a large Stokes shift (50-70 nm), making it an ideal light source material for underwater wireless optical communication. Underwater wireless optical communication application tests and underwater real-time audio transmission demonstrations have verified its stable and reliable communication performance and broad engineering application potential.

Description

Technical Field

[0001] This invention belongs to the field of optical functional materials and underwater communication technology, specifically relating to a self-crystallizing borosilicate glass, its preparation method, and its application. Technical Background

[0002] Underwater wireless optical communication has become a core technology in fields such as marine environmental monitoring, underwater robot navigation, and cross-media data exchange due to its advantages such as high-speed data transmission, low latency, strong anti-interference ability, and high confidentiality.

[0003] To ensure stable system operation, underwater wireless optical communication requires a light source with low light attenuation, high photoluminescence quantum yield, and long-term environmental stability. Blue light (480-490 nm) exhibits the lowest light attenuation coefficient in water (α≈0.05 nm). -1 The cyan light spectrum is the preferred band for underwater wireless optical communication, but the lack of mature cyan light communication sources remains a major bottleneck. Although commercial gallium nitride semiconductor lasers are relatively mature in the 400-480 nm band, their blue-green spectral coverage is insufficient, and they suffer from problems such as high power consumption and limited spectral tunability. Cyan light obtained based on other materials such as ZnSe quantum dots [10.1007 / s12274-024-7106-3] and nanosheets [10.1021 / acs.chemmater.2c02164] has a relatively long emission lifetime (~40 ns), which limits the modulation bandwidth and communication rate of the communication system; carbon dots [10.1016 / j.ceramint.2025.06.086] provide a broad emission spectrum (FWHM ≈ 90 nm), resulting in a significantly enhanced scattering effect. Therefore, developing an underwater communication light source with wavelength precisely matched to 480-490nm blue light emission, high photoluminescence quantum yield, strong stability, and low fluorescence lifetime is key to breaking through the bottleneck of underwater wireless optical communication technology. Summary of the Invention

[0004] In view of the technical defects of existing underwater wireless optical communication light sources, the primary objective of this invention is to provide a self-crystallizing borosilicate glass.

[0005] Another object of the present invention is to provide a method for preparing self-crystallizing borosilicate glass.

[0006] Another object of the present invention is to provide an application of the above-mentioned self-crystallizing borosilicate glass, specifically for underwater wireless optical communication after the nanocrystalline glass is assembled with four parallel 365 nm chips to form a communication light source.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A self-crystallizing borosilicate glass comprises a borosilicate glass matrix and perovskite nanocrystals uniformly dispersed in the glass matrix.

[0009] Preferably, the perovskite nanocrystals are CsPbCl. 1.5 Br 1.5 The average particle size is 1~5nm, more preferably 1~3nm.

[0010] Preferably, the molar percentages of the raw material components of the self-crystallizing borosilicate glass are as follows:

[0011] H3BO3: 20~60 mol%, GeO2: 20~30 mol%, ZnO: 1~10 mol%, SrCO3: 1~10 mol%, PbO: 2~10 mol%, Ta2O5: 0.5~5 mol%, Cs2CO3: 3~10 mol%, M1Cl: x mol%, M2Br: x mol%, 2≤x≤8; M1 and M2 are both selected from alkali metal ions.

[0012] Preferably, the molar percentages of the raw material components of the self-crystallizing borosilicate glass are as follows:

[0013] H3BO3: 40~60 mol%, GeO2: 20~30 mol%, ZnO: 5~10 mol%, SrCO3: 1~5 mol%, PbO: 2~5 mol%, Ta2O5: 0.5~2 mol%, Cs2CO3: 3~5 mol%, M1Cl: x mol%, M2Br: x mol%, 4≤x≤6; M1 and M2 are selected from Na + or K + .

[0014] Preferably, the photoluminescence emission peak of the self-crystallizing borosilicate glass is centered at 480~490nm, the full width at half maximum (FWHM) of the emission peak is 20~40nm, the fluorescence lifetime is 5~10ns, the photoluminescence quantum yield is ≥50%, and the Stokes shift is 50~70nm.

[0015] A method for preparing the above-mentioned self-crystallizing borosilicate glass includes the following steps:

[0016] (1) Calculate and weigh the raw materials according to the composition of self-crystallizing borosilicate glass, mix and melt the raw materials to obtain glass melt;

[0017] (2) Pour the molten glass described in step (1) onto the mold to obtain a transparent and uniform glass body;

[0018] (3) After annealing the glass body described in step (2), it is cooled to obtain self-crystallizing borosilicate glass.

[0019] Preferably, the melting temperature in step (1) is 980±50℃;

[0020] In step (2), the mold is preheated to 350~480℃ before casting, and the mold is a graphite mold.

[0021] Preferably, the annealing temperature in step (3) is 420±50℃ and the time is 3~7h;

[0022] The cooling in step (3) is to cool to room temperature at a cooling rate of 5~10℃ / h.

[0023] The above-mentioned self-crystallizing borosilicate glass is used in the field of underwater wireless optical communication.

[0024] Preferably, the above-mentioned self-crystallizing borosilicate glass and 365 nm chip are assembled into a communication light source for use in the field of underwater wireless optical communication.

[0025] The above-mentioned application of self-crystallizing borosilicate glass in real-time underwater audio transmission.

[0026] Preferably, the above-mentioned self-crystallizing borosilicate glass and 365 nm chip are assembled into a communication light source for real-time underwater audio transmission.

[0027] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0028] (1) The nanocrystalline glass of the present invention adopts the "in-situ self-crystallization" strategy to replace the traditional "synthesis and encapsulation" method. The perovskite nanocrystals (average size of 1.797 nm) are directly nucleated and grown from the glass melt and seamlessly integrated with the glass matrix. The rigid BO-Ge glass network realizes the physical confinement of the nanocrystals, so that the power instability is less than 5% under high intensity power density excitation. The 488 nm blue light narrow band emission peak of the nanocrystalline glass is in the low light decay core band in water, and the half width at half maximum of the emission peak is about 30 nm. It has the advantages of high quantum yield (54.5%) and low fluorescence decay lifetime (6.71~9.67 ns).

[0029] (2) The present invention assembles nanocrystalline glass with four parallel 365 nm chips into a communication light source. The signal received after transmission in water for 0.8 m was tested. The waveforms at all frequencies were undistorted, and the received square wave signal had only a small amount of attenuation.

[0030] (3) This invention tested the received signals before and after 0.5 m of transmission in water with and without audio input of various types. The demodulated and restored audio signals were undistorted and clearly identifiable. This demonstrates that the self-crystallized bluish-green borosilicate glass of this invention is stable, reliable, and has great potential as a communication light source in underwater wireless optical communication applications. Attached Figure Description

[0031] Figure 1 The emission spectrum (a) and crystallization activation energy (b) of the glass sample in Example 1 of this invention are shown.

[0032] Figure 2 TEM tests (a), lifetime (b), and quantum yield tests (c) of the glass sample in Example 1 of this invention.

[0033] Figure 3 The emission spectrum (a) and lifetime (b) of the glass sample in Example 2 of the present invention are shown.

[0034] Figure 4 This is a comparison of the emission spectra of glass samples from Example 3 and Example 1 of the present invention under the same excitation.

[0035] Figure 5 The emission and absorption spectra of Example 1 (a) and Comparative Example 1 (b) are shown.

[0036] Figure 6 The color coordinates (a) and power stability test (b) of the communication light source assembled by assembling a glass sample with four parallel 365 nm chips in Examples 5 and 6 are shown.

[0037] Figure 7 This is a schematic diagram of the experimental setup for underwater wireless optical communication using a communication light source, as shown in Example 5.

[0038] Figure 8 Example 5 illustrates the transmission of a communication light source in water.

[0039] Figure 9 The diagram shows the experimental setup (a) for real-time underwater audio transmission using a communication light source in Example 6, and the transmission status (b) in the water. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings. However, the implementation of the present invention is not limited thereto. For process parameters not specifically noted, conventional techniques can be referred to.

[0041] Example 1

[0042] The composition of the self-crystallizing bluish-green borosilicate glass in this embodiment is as follows:

[0043] H3BO3: 51mol%, GeO2: 27 mol%, ZnO: 5 mol%, SrCO3: 2 mol%, PbO: 2 mol%, Ta2O5: 1mol%, Cs2CO3: 3mol%, NaCl: 4.5 mol%, NaBr: 4.5 mol%.

[0044] The preparation method of self-crystallizing bluish-green borogermanate glass is as follows:

[0045] Based on the raw material composition, high-purity (≥99.9%) powdered raw materials of H3BO3, GeO2, ZnO, SrCO3, PbO, Ta2O5, Cs2CO3, NaCl, and NaBr were ground evenly and placed in a corundum crucible. The mixture was then melted in a furnace at 980 ℃ for 30 min to obtain molten glass. This molten glass was directly poured into a graphite mold preheated to 420 ℃ in an annealing furnace. After holding at 420 ℃ for 5 h in the annealing furnace, it was cooled to room temperature at a rate of 10 ℃ / h to obtain self-crystallizing bluish-green borosilicate glass. The prepared glass sample was processed into a circular glass plate with a thickness of 1-2 mm and a diameter of 3 cm, as well as several smaller glass samples, for performance characterization.

[0046] Example 2

[0047] The NaCl and NaBr in Example 1 were replaced with KCl and KBr, respectively, to obtain a glass sample with an emission peak at 480-490 nm and a fluorescence lifetime of 6.71 ns.

[0048] Example 3

[0049] The composition of the self-crystallizing bluish-green borogermanate glass is as follows:

[0050] H3BO3: 49mol%, GeO2: 25 mol%, ZnO: 5 mol%, SrCO3: 2 mol%, PbO: 3 mol%, Ta2O5: 1mol%, Cs2CO3: 4mol%, NaCl: 5.5 mol%, NaBr: 5.5 mol%.

[0051] When the molar percentages of PbO, Cs2CO3, NaCl, and NaBr in Example 1 are all increased by 1 mol%, the luminescence of the glass sample is enhanced. The stronger the luminescence, the better it is for increasing the communication distance when the glass is used for underwater wireless optical communication.

[0052] Example 4

[0053] The composition of the self-crystallizing bluish-green borogermanate glass is as follows:

[0054] H3BO3: 48.5 mol%, GeO2: 24.5 mol%, ZnO: 5 mol%, SrCO3: 2 mol%, PbO: 3 mol%, Ta2O5: 1 mol%, Cs2CO3: 4 mol%, NaCl: 6 mol%, NaBr: 6 mol%.

[0055] When the molar percentages of NaCl and NaBr in Example 1 are both increased to 6 mol%, the glass sample exhibits the strongest luminescence, indicating that the glass matrix has reached its maximum capacity to accommodate nanocrystals. Further increases in mol% result in no further increase in luminescence intensity, as the nanocrystals adhere to the glass surface during glass forming and cannot precipitate within the glass matrix.

[0056] Comparative Example 1

[0057] When Ta2O5 was removed from the glass sample in Example 1 and H3BO3 (52 mol%) was added in equal amounts, the resulting glass sample exhibited a very small Stokes shift. Figure 5 The absorption and emission peaks shown in b have an overlap, while the Stokes shift (66 nm) in Example 1 is much larger. Figure 5 As shown in a, it indicates that the self-absorption phenomenon of the glass sample is severe when Ta2O5 is removed, which leads to a decrease in the luminescence intensity of the glass.

[0058] Comparative Example 2

[0059] When PbO in Example 1 was replaced with CuO, the resulting glass sample required heat treatment to emit ultraviolet light, indicating that a second heat treatment was needed to achieve crystal precipitation, and no self-crystallization occurred. Moreover, after heat treatment, it could only emit ultraviolet light and could not be modulated to the target band suitable for underwater wireless optical communication.

[0060] Comparative Example 3

[0061] When any one of the three materials in Example 1—metal halide, PbO, and Cs2CO3—was removed, the resulting glass samples did not emit light, indicating that no crystals precipitated in the glass samples. These three materials are the source of nanocrystals.

[0062] The glass sample obtained in Example 1 was subjected to performance characterization:

[0063] The emission spectrum was tested using a Horiba FL3-211 fluorescence spectrometer. The excitation source was a 450 W xenon lamp, and the excitation wavelength was 365 nm. The glass sample, which was polished to a uniform thickness, was placed in the corresponding position in the test cell, and the scanning step and other relevant parameters were set for testing.

[0064] The test method for the lifetime of glass samples is as follows: it is performed by a Horiba FL3-211 fluorescence spectrometer from France. The excitation source is an external laser at 450 nm. The glass sample, which has been polished to a uniform thickness, is placed in the corresponding position in the test cell. The scanning step size and other relevant parameters are set for testing. The lifetime of the glass sample is then calculated by double exponential fitting.

[0065] The quantum yield test method is as follows: a spectrometer equipped with an integrating sphere is used for testing. The excitation source is a 365 nm laser. A glass sample that has been polished to a uniform thickness is placed in the corresponding position of the test cell. The corresponding parameters such as the scanning step size are set for testing.

[0066] The emission spectrum of the glass sample in Example 1 is as follows: Figure 1 As shown in a, the center of the emission peak is 488 nm, which is in the low light decay core band in water, and the full width at half maximum (FWHM) of the emission peak is about 30 nm. Figure 1 In the figure, b is the crystallization activation energy calculated using the Ozawa method and the Kissinger method based on the crystallization peak temperature Tc. The relatively low activation energy obtained (144.60~157.53 kJ / mol) ensures the smooth in-situ self-crystallization of nanocrystals. Figure 2 In the TEM test of a, nanocrystals and obvious lattice fringes were observed to be uniformly distributed in the glass matrix, and the average size was calculated to be 1.797 nm. Figure 2 The lifetime and quantum yield of the glass sample were tested using bc, which were 9.67 ns and 54.5%, respectively.

[0067] Example 5: Application of self-crystallizing bluish-green borosilicate glass in underwater wireless optical communication

[0068] The glass sample obtained in Example 1 was assembled with four parallel 365 nm chips and a heat dissipation device into a communication light source (such as...). Figure 6 As shown in illustration a), the color coordinates of this communication light source are located at (0.1693, 0.3091), and it exhibits high cyan purity; as Figure 6 As shown in b, at a power density of 3.59 kW / cm² 2 Under the excitation of [the light source], the power instability is less than 5%, demonstrating the great potential of this communication light source to work stably for a long time in underwater wireless optical communication applications.

[0069] An underwater wireless optical communication application platform was constructed, and the communication light source was applied to underwater wireless optical communication. The schematic diagram of the underwater wireless optical communication system is shown below. Figure 7 As shown, the pulse generator produces a 5-30 kHz square wave signal (high level is 5V, low level is 0V), illuminating the communication light source of this invention. The emitted blue light is collimated by a collimating lens and transmitted in the underwater channel, where it is received by a photodetector and detected by an oscilloscope; as shown... Figure 8 As shown, the signal received after transmission in water for 0.8 m was tested. It can be found that the waveforms at all frequencies are undistorted, and the received square wave signal has only a small amount of attenuation, which proves the capability of the communication light source of the present invention in underwater wireless optical communication applications.

[0070] Example 6: Application of self-crystallizing bluish-green borosilicate glass in real-time underwater audio transmission

[0071] Based on the underwater wireless optical communication application platform constructed in Example 5, a circuit board capable of loading audio signals was added to apply the communication light source to real-time underwater audio transmission. The schematic diagram of the experimental setup for real-time underwater audio transmission is shown below. Figure 9 As shown in diagram a, the edited audio signals "S", "C", "U", "T" and "SCUT" are loaded onto the circuit board via a radio receiver. A 5V constant voltage source is applied to the circuit board's voltage input. A communication light source emits blue light modulated by the audio signal. After transmission through the underwater channel, the signal is received by a photodetector, and the received signal is detected by an oscilloscope. Figure 9 As shown in b, the signals received before and after 0.5 m of transmission in water were tested with and without audio input, as well as with various types of audio input. The demodulated and restored audio signals were undistorted and clearly identifiable, further demonstrating the ability of the communication light source of this invention to communicate in real time underwater.

[0072] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A self-crystallizing borosilicate glass, characterized in that, It includes a borosilicate glass matrix and perovskite nanocrystals uniformly dispersed in the glass matrix.

2. The self-crystallizing borosilicate glass according to claim 1, characterized in that, The perovskite nanocrystal is CsPbCl 1.5 Br 1.5 , and the average particle size is 1-5 nm.

3. The self-crystallizing borosilicate glass according to claim 1, characterized in that, The molar percentages of the raw material components for the self-crystallizing borosilicate glass are as follows: H3BO3: 20~60 mol%, GeO2: 20~30 mol%, ZnO: 1~10 mol%, SrCO3: 1~10 mol%, PbO: 2~10 mol%, Ta2O5: 0.5~5 mol%, Cs2CO3: 3~10 mol%, M1Cl: x mol%, M2Br: x mol%, 2≤x≤8; M1 and M2 are both selected from alkali metal ions.

4. The self-crystallizing borosilicate glass according to claim 3, characterized in that, The molar percentages of the raw material components for the self-crystallizing borosilicate glass are as follows: H3BO3: 40~60 mol%, GeO2: 20~30 mol%, ZnO: 5~10 mol%, SrCO3: 1~5 mol%, PbO: 2~5 mol%, Ta2O5: 0.5~2 mol%, Cs2CO3: 3~5 mol%, M1Cl: x mol%, M2Br: x mol%, 4≤x≤6; M1, M2 are selected from Na + or K + .

5. The self-crystallizing borosilicate glass according to claim 1, characterized in that, The photoluminescence emission peak of the self-crystallizing borosilicate glass is centered at 480~490nm, with a full width at half maximum (FWHM) of 20~40nm, a fluorescence lifetime of 5~10ns, a photoluminescence quantum yield ≥50%, and a Stokes shift of 50~70nm.

6. A method for preparing the self-crystallizing borosilicate glass according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Calculate and weigh the raw materials according to the composition of self-crystallizing borosilicate glass, mix and melt the raw materials to obtain glass melt; (2) Pour the molten glass described in step (1) onto the mold to obtain a transparent and uniform glass body; (3) After annealing the glass body described in step (2), it is cooled to obtain self-crystallizing borosilicate glass.

7. The method for self-crystallizing borosilicate glass according to claim 6, characterized in that, The melting temperature in step (1) is 980±50℃; In step (2), the mold is preheated to 350~480℃ before casting, and the mold is a graphite mold.

8. The method for self-crystallizing borosilicate glass according to claim 6, characterized in that, The annealing temperature in step (3) is 420±50℃, and the time is 3~7h; The cooling in step (3) is to cool to room temperature at a cooling rate of 5~10℃ / h.

9. The application of the self-crystallizing borosilicate glass according to any one of claims 1 to 5 in the field of underwater wireless optical communication.

10. The application of the self-crystallizing borosilicate glass according to any one of claims 1 to 5 in real-time underwater audio transmission.

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