High-density erasable information storage glass for improving solubility of silver ions based on negatively charged network polyhedrons and preparation method of high-density erasable information storage glass

Abstract

The invention discloses high-density erasable information storage glass for improving solubility of silver ions based on a negatively charged network polyhedron and a preparation method of the high-density erasable information storage glass. The high-density erasable information storage glass comprises the following components in percentage by mole: 20-35% of a positively charged network former [PO4] < + >; the content of negatively charged network intermediates [AlO4] <->, [MgO4] < 2-> and [ZnO4] < 2-> is 10-20%, the content of network extrinsic cations Al < 3 + >, Mg < + > and Y < 3 + > is 25-40%, and the content of activating agent silver ions is 10-20%; the proportion of bridge oxygen connected with the network forming body and non-bridge oxygen connected with the network outer body is 40-60%, and the laser erasing wave band is 400-800 nm. The fluorescent glass is fired by adopting a high-temperature melting method and is processed by adopting femtosecond laser, so that the fluorescent glass has a relatively low laser damage threshold value, Ag < + > in the glass has relatively high laser sensitivity and relatively high chemical stability, and continuous erasing of micro-area information storage can be realized through continuous laser.

Description

Technical Field

[0001] The present invention belongs to the field of information storage glass, and in particular relates to a high-density erasable information storage glass based on negatively charged network polyhedrons to improve the solubility of silver ions and a preparation method thereof. Background Art

[0002] Recently, the rapid development of femtosecond laser technology is expected to cleverly solve the contradiction between the photosensitivity required for high-speed reading and writing of large-capacity optical storage materials and the stability required for long life. Femtosecond laser has a very narrow pulse width and an energy density of up to 10 14 -10 15 W / cm 2 This exceeds the Coulomb field strength of a hydrogen atom. Therefore, near the focal point, even if the material itself lacks intrinsic absorption at the laser wavelength, laser-induced nonlinear reactions such as multiphoton absorption and multiphoton ionization can achieve highly spatially selective microstructural modification and endow the material with unique optical functions. This advantage is unmatched by other laser light sources (conventional continuous and long-pulse lasers).

[0003] Fluorescent silver quantum clusters, [Ag m ] x+ , is a molecular cluster composed of several to dozens of silver atoms or ions, and is also a new, efficient, multi-order femtosecond laser-induced fluorescence information carrier. [Ag m ] x+ It has a sub-nanometer size comparable to the electron Fermi wavelength, a molecular-like energy level structure determined by the quantum confinement effect, and molecular-like high-efficiency fluorescence. It has low optical sensitivity suitable for low-power femtosecond laser writing. Its valence state is easier to control and the cost of raw materials is also low. Therefore, as a low-threshold fluorescence active center, it is considered to have better comprehensive performance than other precious metal quantum clusters such as copper, gold and platinum. At the same time, inorganic glass is considered to be one of the best medium materials for femtosecond laser information storage, with very good physical and chemical stability, especially low optical sensitivity and high laser damage threshold. Due to the fluorescence [Ag m ] x+ Quantum clusters are highly chemically active, so dispersing them in the glass network is also beneficial for stabilizing their size distribution and fluorescence properties. + Microstructure rewriting with spatial resolution in glass, Ag + The electrons that are susceptible to laser-induced ionization are reduced and aggregate to form fluorescent [Ag m ] x+ Quantum clusters.

[0004] Network extracellular Y 3+The role of connecting the glass network structure is different from that of alkaline earth metals (such as Na, K, Ca and Ba). The electric field strength of Y ions is K (Y 3+ ) = 3.75, which is greater than the electric field strength of any other alkaline earth metal ion. When Y2O3 is introduced into a glass system in large quantities, unlike other alkaline earth metal ions that exhibit crystallization, [YO6] octahedra are connected by shared edge oxygens to form a glass network, similar to a differential phase within the glass. This glass network prevents crystallization and can connect multiple phosphate segments to form a three-dimensional network structure. The formation of this hybrid network not only increases the proportion of non-bridging oxygen within the glass network but also, when the glass is irradiated by a femtosecond laser, ionic bonds are broken to form silver ion channels, thereby enhancing the sensitivity of the silver ions to the femtosecond laser.

[0005] The mechanism of the formation of silver quantum clusters induced by femtosecond laser is as follows: When the initial series of femtosecond laser pulses interact with the glass mechanism, Ag+ and the phosphate matrix generate a large number of free electrons through multi-photon absorption, which leads to the formation of silver quantum clusters. 0 Formation (Ag + +e - →Ag 0 ), the reaction rate depends on the doping concentration and the degree of electron diffusion. However, the process of forming silver quantum clusters is an irreversible reaction, which means that it is very difficult to erase the information stored in the micro-area. At present, in the field of laser information storage, there are two common methods for erasing: 1. In the field of laser storage perovskite quantum dot glass, the general method is to use femtosecond laser to achieve micro-area erasing. The limitation of this method is that the cost of femtosecond laser erasing is expensive, and there is currently no literature report on the erasing of silver clusters by this method; 2. By subjecting the glass with micro-area signals engraved thereto to heat treatment at a temperature slightly higher than the glass transition point, the silver quantum clusters in the glass are made to flow, thereby achieving erasability of the signal. The disadvantage is that this method is to achieve thermal erasure of the entire glass through heat treatment, and cannot achieve micro-area signal erasure. Secondly, the erasing process will generate silver quantum clusters, which will cause great loss to the glass information storage. Summary of the Invention

[0006] In order to overcome the above-mentioned shortcomings of the prior art, the present invention provides a high-density erasable information storage glass based on negatively charged network polyhedrons to improve the solubility of silver ions. The glass prepared by the high-temperature melting method of the present invention contains Ag. + It has high laser sensitivity and high chemical stability, adopts femtosecond laser processing, has a low laser damage threshold, and then uses a series of continuous lasers to achieve continuous erasure of micro-area information storage. The laser erasure band is 400-800nm. The present invention develops a glass component and technology that can achieve repeated erasure of silver quantum cluster micro-areas through femtosecond laser erasure:

[0007] A high-density erasable information storage glass based on negatively charged network polyhedrons to improve the solubility of silver ions, wherein the network former cations, network intermediate cations, network exosome cations and activator silver ions have the following stoichiometric ratios in molar percentage:

[0008]

[0009] Among them, the positively charged network former is [PO4] + ; The negatively charged network intermediate is [AlO4] - ,[MgO4] 2- and [ZnO4] 2- ; The external cation of the network is Al 3+ Mg + 、Y 3+ .

[0010] Furthermore, in terms of molar percentage, the bridging oxygen connected to the network former and the non-bridging oxygen connected to the network exogenous body have the following stoichiometric ratio: 40-60% of bridging oxygen and 40-60% of non-bridging oxygen.

[0011] A method for preparing high-density erasable information storage glass based on negatively charged network polyhedrons to improve the solubility of silver ions comprises:

[0012] (1) Weighing the required mass of the oxide and fluoride powder raw materials corresponding to the cations in molar percentage;

[0013] (2) uniformly mixing the oxide powder raw materials corresponding to the cations, pouring them into a mold after melting to form a glass block, and annealing to remove internal stress;

[0014] (3) Using femtosecond laser to write at a predefined depth below the glass surface, the femtosecond laser pulse interacts with the glass to write the Ag + Silver clusters with a molecular structure composed of ions and Ag atoms;

[0015] (4) Erasing the micro-area written pattern using a continuous laser;

[0016] (5) Repeat steps (3) and (4) multiple times to obtain a silver ion information storage glass that can be erasable multiple times.

[0017] Furthermore, in step (1), the corresponding oxide and fluoride powder raw materials include: P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF2 and Ag2O.

[0018] Furthermore, in step (2), the melting temperature is 1200-1550° C., and the melting time is 0.5-3 hours.

[0019] Furthermore, in step (2), the annealing temperature is 300-400° C., and the holding time is 12-24 hours.

[0020] Furthermore, in step (3), the wavelength of the femtosecond laser is 1030 nm; and the predefined depth is 100 μm.

[0021] Furthermore, in step (4), the wavelength range of the continuous laser is 400 to 800 nm.

[0022] The technical solutions provided by the embodiments of the present application may have the following beneficial effects:

[0023] The present invention can form [AlO4] by reasonably introducing raw materials such as ZnF2, MgF2 and AlF3. - ,[MgO4] 2- and [ZnO4] 2- The iso-negatively charged tetrahedral units improve the connectivity of the glass three-dimensional network, while Ag + Ions act as charge compensators for these tetrahedra, promoting uniform distribution and forming [ZnO6], [MgO6] and [AlO6] to generate a large amount of non-bridging oxygen to connect Ag. + ions; high concentration of non-bridging oxygen, solubility strategy introduces fluoride into pure oxide glass to destroy the fluorophosphate bond to produce a large amount of non-bridging oxygen and Ag + connection, thereby achieving a higher silver ion concentration.

[0024] High concentration of rare earth Y doped phosphate glass forms a large number of non-bridging oxygen. [YO6] octahedrons can form an inverse glass structure to connect the broken chains of phosphate phase separation, which can generate a large number of non-bridging oxygen structures to connect and stabilize Ag. + , and can form Ag after femtosecond laser irradiation + The migration channel of the glass network is highly sensitive to laser. The glass network forms a large amount of non-bridging oxygen and fluoride, which makes the laser damage threshold of the glass low. It can achieve ion rearrangement in the network structure with a single pulse of low energy, further reducing the energy loss of femtosecond laser processing.

[0025] This application provides a technology that can repeatedly erase and rewrite micro-area silver clusters using continuous lasers, filling a major gap in femtosecond laser information storage and erasing silver ions. It also provides a technology for erasing silver quantum cluster signals using visible continuous lasers. By irradiating the femtosecond laser-processed micro-area where the signal is recorded with continuous laser light for a certain period of time, the signal is erased. The erased signal area can then be reprocessed with a new signal using the femtosecond laser. This application uses continuous lasers to achieve micro-area signal erasure, which is both low-cost and precise, reducing losses during the erasable process.

[0026] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0028] Figure 1 is the X-ray photoelectron spectrum of O1s in the glass sample obtained in Example 1;

[0029] Figure 2 This is the X-ray photoelectron spectrum of Al coordination in the glass sample obtained in Example 2;

[0030] Figure 3 This is the X-ray photoelectron spectrum of Al coordination in the glass sample obtained in Example 3;

[0031] Figure 4 This is the X-ray photoelectron spectrum of Al coordination in the glass sample obtained in Example 4;

[0032] Figure 5 The micro-region fluorescence mapping images of the glass sample obtained in Example 1 after laser erasure at 561 nm, where (a)-(d) are the micro-region fluorescence mapping images after laser erasure at 0s, 6s, 12s, and 18s, respectively;

[0033] Figure 6 The micro-region fluorescence mapping images of the glass sample obtained in Example 2 after laser erasure at 488 nm, where (a)-(d) are the micro-region fluorescence mapping images after laser erasure at 0s, 6s, 12s, and 18s, respectively;

[0034] Figure 7 The micro-region fluorescence mapping images of the glass sample obtained in Example 3 after laser erasure at 639 nm, where (a)-(d) are the micro-region fluorescence mapping images after laser erasure at 0s, 6s, 12s, and 18s, respectively;

[0035] Figure 8 The micro-region fluorescence mapping images of the glass sample obtained in Example 4 after laser erasure at 405 nm, where (a)-(d) are the micro-region fluorescence mapping images after laser erasure for 0 s, 6 s, 12 s, and 18 s, respectively;

[0036] Figure 9 Schematic diagram of repeated erasure of the glass sample obtained in Example 1. DETAILED DESCRIPTION

[0037] Exemplary embodiments are described in detail herein, with examples illustrated in the accompanying drawings. When the following description refers to the drawings, identical numerals in different drawings represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with this application.

[0038] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. As used in this application and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0039] It should be noted that, unless there is any conflict, the features in the following embodiments and implementations may be combined with each other.

[0040] According to the random network theory of glass, in the fluoroaluminophosphate glass of the present invention, the glass is mainly [PO4] + 、[AlO4] - , where [PO4] + Q2 and Q1 mainly form a chain structure, [AlO4] - Q4 and Q3 can connect different phosphorus-oxygen chains, which has the effect of improving the three-dimensional connectivity of the phosphorus-oxygen network. + The concentration of [AlO4] in glass can be achieved by two strategies: (1) by introducing negatively charged [AlO4] - 、[ZnO4] 2- With [MgO4] 2- Tetrahedron can significantly improve the dispersion uniformity of Ag and improve the + / (Ag + +Ag 0 (2) The formation of [P(O,F)4] in the glass system breaks the glass network, and the high electronegativity [YO6] not only increases the non-bridging oxygen ratio, but also connects the broken network chains. + It can also coordinate with non-bridging oxygen, thus increasing the Ag content of the glass system. + Solubility, that is, the formation of glass system Ag + / (Ag + +Ag 0 The present invention realizes a high-concentration non-bridging oxygen coordinated silver ion information storage glass with high density information, which can provide a new material basis for the development of low-energy high-density information storage technology.

[0041] Continuous laser irradiation in micro-areas can generate a large amount of heat accumulation, causing the local temperature of the glass to be higher than the glass transition point, thereby accelerating the ion migration rate in the local area, and the silver quantum clusters in the glass migrate, leaving the previous femtosecond laser writing area and spreading around, causing the fluorescence of the glass micro-area to disappear; and after using laser irradiation to write information again, the femtosecond laser can not only make new quantum clusters grow in the glass, but also make the silver quantum clusters that were originally dispersed in the glass re-aggregate in the irradiated area, so that the information intensity of the second writing remains very high.

[0042] Example 1

[0043] Step S1: Weigh the required amounts of P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O in molar percentages. Powder raw materials: P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O are mixed uniformly and placed in a corundum crucible. In this composition, Ag2O accounts for 10% of the total molar weight of the separated fluorophosphates, AlF3, MgF2, and ZnF2 each account for 5% of the total molar weight of the fluorophosphates, P2O5 and Al2O3 account for 30% and 15%, respectively, and Y2O3 accounts for 30%.

[0044] Step S2: Place the glass in a 1450°C box-type electric furnace for 45 minutes of heat preservation and pour into a mold to form a glass block. Place the glass block at 300°C for 12 hours to remove internal stress. Polish the glass to a surface of 3000 mesh and then perform femtosecond laser micro-processing. Then, take the powder and test XPS. Figure 1 The XPS image shows that the non-bridging oxygen concentration in the glass obtained in this example is 50.4%, enabling the rapid formation of silver ion channels under femtosecond laser processing, which is conducive to the formation of fluorescent silver clusters. Femtosecond laser processing conditions were 200kHz single pulse, 60nJ. The processed area was observed under a confocal microscope. The femtosecond laser-engraved micro-area signal was then erased using a 2W 561nm continuous laser. The system was preset to have a residual fluorescence intensity of 10%. After 24 seconds, the residual fluorescence intensity was 35%. Generally, extended erasure time is required for effective erasure.

[0045] Example 2

[0046] Step S1: Weigh the required amounts of P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O in molar percentages. Powder raw materials: P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O are mixed uniformly and placed in a corundum crucible. The composition comprises: Ag2O accounting for 10% of the total molar amount of the fluorophosphate; ZnF2 accounting for 15% of the total molar amount of the fluorophosphate; AlF3 and MgF2 each accounting for 2.5% of the total molar amount of the fluorophosphate; P2O5 and Al2O3 accounting for 30% and 20%, respectively; and Y2O3 accounting for 20%.

[0047] Step S2: Then, the glass is placed in a 1450°C box-type electric furnace for 45 minutes of heat preservation and melting, and then poured into a mold to form a glass block. The glass block is placed at 300°C for 16 hours to remove internal stress. Figure 2 The XPS image of the glass obtained for this example shows that [AlO4] accounts for 53.7%, and the negatively charged [AlO4] - It can greatly improve the stability of glass seed silver. After the glass was polished to a surface of 3000 mesh, it was subjected to femtosecond laser micro-processing. The femtosecond laser processing conditions were 200kHz single pulse, 60nJ, and the processed area was observed under a confocal microscope. The micro-area signal written by the femtosecond laser was then erased using a 2W 488nm continuous laser. The system preset the residual fluorescence intensity to 10%. Finally, after 24 seconds, the residual fluorescence intensity was 14%, indicating a good erasure effect and meeting the requirements.

[0048] Example 3

[0049] Step S1: Weigh the required amounts of P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O in molar percentages. Powder raw materials: P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O are mixed uniformly and placed in a corundum crucible. The composition comprises: Ag2O accounting for 10% of the total molar amount of the fluorophosphate; MgF2 accounting for 15% of the total molar amount of the fluorophosphate; AlF3 and ZnF2 each accounting for 2.5% of the total molar amount of the fluorophosphate; P2O5 and Al2O3 accounting for 30% and 20%, respectively; and Y2O3 accounting for 20%.

[0050] Step S2: Then, the glass is placed in a 1450°C box-type electric furnace for 45 minutes of heat preservation and melting, and then poured into a mold to form a glass block. The glass block is placed at 300°C for 24 hours to remove internal stress. Figure 3 The XPS image of the glass obtained for this example shows that [AlO4] accounts for 57%, and the negatively charged [AlO4] -Improvements can further enhance the stability of silver in glass. After polishing the glass to a 3000-mesh surface, femtosecond laser micro-processing was performed using a 200kHz single pulse at 60nJ. The processed area was observed under a confocal microscope. A 10W 639nm continuous laser was then used to erase the micro-area signal written by the femtosecond laser. The system preset a residual fluorescence intensity of 10%. After 24 seconds, the remaining fluorescence intensity was 41%, indicating poor erasure effectiveness and requiring further laser erasure time.

[0051] Example 4

[0052] Step S1: Weigh the required amounts of P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O in molar percentages. Powder raw materials: P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF, and Ag2O are mixed uniformly and placed in a corundum crucible. The composition comprises: Ag2O accounting for 10% of the total molar amount of the fluorophosphate; AlF3 accounting for 15% of the total molar amount of the fluorophosphate; MgF2 and ZnF2 each accounting for 2.5% of the total molar amount of the fluorophosphate; P2O5 and Al2O3 accounting for 30% and 20%, respectively; and Y2O3 accounting for 20%.

[0053] Step S2: Place the glass in a 1450°C box-type electric furnace for 45 minutes of heat preservation and melting, pour it into a mold to form a glass block, and place the glass block at 300°C for 20 hours to remove internal stress. Figure 4 The XPS image of the glass obtained in this embodiment shows that [AlO4] accounts for 64.1%. Compared with Examples 2 and 3, the negatively charged [AlO4] in the glass obtained in this embodiment is - The glass was polished to a 3000-mesh surface before undergoing femtosecond laser micro-processing. The processing conditions were a 200kHz single pulse at 60nJ. The processed area was observed under a confocal microscope. A 10W 405nm continuous laser was then used to erase the micro-area signal written by the femtosecond laser. The system preset the residual fluorescence intensity to 10%. After 24 seconds, the residual fluorescence intensity was 10%, indicating excellent erasure results and meeting the application requirements.

[0054] Table 1 Fluorescence intensity of the glass sample obtained in Example 4 after multiple erasures and re-input of the signal

[0055] Erasure times 1 2 3 5 10 Writing fluorescence intensity / first writing fluorescence intensity (%) 92 86 80 68 54

[0056] Depend on Figure 5-8After continuous laser erasure at different wavelengths for the same time and under the same conditions, the residual fluorescence intensity in the glass is 639nm>561nm>488nm>405nm, and the residual fluorescence intensity is 41%>35%>14%>10% respectively. The shorter the continuous laser erasing wavelength, the better the erasing effect. The erasable glass of this system can still be written after multiple erasures. Figure 9 The figure shows the fluorescence intensity after the second erasing and writing. Table 1 shows that after 10 writing cycles, the fluorescence intensity is still 54%.

[0057] Those skilled in the art will readily conceive of other embodiments of the present application after considering the specification and practicing the contents disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of this application and include common knowledge or customary techniques in the art that are not disclosed in this application.

Claims

1. A high-density erasable information storage glass based on negatively charged network polyhedrons to improve the solubility of silver ions, characterized in that: In terms of molar percentage, the network former cations, network intermediate cations, network exo-cations and activator silver ions have the following stoichiometric ratios: Among them, the positively charged network former is [PO4] + ; The negatively charged network intermediate is [AlO4] - ,[MgO4] 2- and [ZnO4] 2- ; The external cation of the network is Al 3+ Mg + 、Y 3+ .

2. The high-density erasable information storage glass according to claim 1, characterized in that: In terms of molar percentage, the bridging oxygen connected to the network former and the non-bridging oxygen connected to the network exogenous body have the following stoichiometric ratio: 40-60% of bridging oxygen and 40-60% of non-bridging oxygen.

3. A method for preparing high-density erasable information storage glass based on negatively charged network polyhedrons to improve the solubility of silver ions, characterized in that: (1) Weighing the required mass of the oxide and fluoride powder raw materials corresponding to the cations in molar percentage; (2) uniformly mixing the oxide powder raw materials corresponding to the cations, pouring them into a mold after melting to form a glass block, and annealing to remove internal stress; (3) Using femtosecond laser to write at a predefined depth below the glass surface, the femtosecond laser pulse interacts with the glass to write the Ag + Silver clusters with a molecular structure composed of ions and Ag atoms; (4) Erasing the micro-area written pattern using a continuous laser; (5) Repeat steps (3) and (4) multiple times to obtain a silver ion information storage glass that can be erasable multiple times.

4. The preparation method according to claim 3, characterized in that In step (1), the corresponding oxide and fluoride powder raw materials include: P2O5, Al2O3, AlF3, Y2O3, MgF2, ZnF2 and Ag2O.

5. The preparation method according to claim 3, characterized in that In step (2), the melting temperature is 1200-1550° C., and the melting time is 0.5-3 hours.

6. The preparation method according to claim 3, characterized in that In step (2), the annealing temperature is 300-400° C. and the holding time is 12-24 hours.

7. The preparation method according to claim 3, characterized in that In step (3), the wavelength of the femtosecond laser is 1030 nm; and the predefined depth is 100 μm.

8. The preparation method according to claim 3, characterized in that In step (4), the wavelength range of the continuous laser is 400 to 800 nm.

Images