Reversible photochromic luminescent material and application thereof

Abstract

The invention relates to the technical field of optical anti-counterfeiting encryption, and particularly discloses a reversible photochromic luminescent material and application thereof, the reversible photochromic luminescent material at least comprises perovskite and a quantum dot doped material, the quantum dot doped material comprises CsPbCl2Br and Yb < 3 + >: CsPbCl2Br quantum dots, and the substance amount ratio of the element Yb / (Yb + Pb) is (1-25): 100. The light stability and the photoluminescence performance of the CsPbCl2Br quantum dot are remarkably improved through Yb < 3 + > doping, and particularly, the CsPbCl2Br quantum dot shows remarkable photoluminescence peak displacement and reversibility under illumination.

Description

Technical Field

[0001] The present invention relates to the field of anti-counterfeiting encryption technology, specifically to reversible photochromic luminescent materials, and also to an application of a reversible photochromic luminescent material. Background Art

[0002] In recent years, due to their excellent optoelectronic properties and tunable photoluminescence characteristics, perovskite materials have gradually become important materials in various optical devices. Especially in the fields of light-emitting diodes (LEDs), solar cells, and optical sensors, the application of perovskite materials has been continuously expanding. Rare earth ions (such as Yb 3+ , Eu 3 +) doped halide perovskite quantum dots exhibit more prominent photochromic properties and photoluminescence effects. Their doping not only enhances the photostability of the material but also significantly improves its performance in terms of dynamic response and optical properties.

[0003] In the fields of optical information storage and anti-counterfeiting encryption, reversible photochromic luminescent materials based on perovskite quantum dots have great application potential. Compared with traditional materials, these materials can quickly respond and achieve efficient color changes under specific light conditions, thus providing a new way for information storage. At the same time, by regulating the structure and doping elements of perovskite quantum dots, their photochromic and photoluminescence characteristics can be precisely adjusted to meet the requirements of high resolution, fast writing and reading, and high-density storage. In anti-counterfeiting encryption technology, perovskite materials can provide highly secure and difficult-to-copy anti-counterfeiting labels through their unique optical response characteristics, enhancing the protection and verification capabilities of information.

[0004] In the future, with the further optimization of perovskite material properties and the continuous progress of technology, perovskite-based photochromic materials will be more widely applied in fields such as smart displays, data storage, and information encryption, promoting the continuous development of smart optical technology. At the same time, with the improvement of the preparation process and the reduction of costs, the industrialization process of perovskite materials will also be accelerated, providing strong support for the popularization and application of these advanced technologies.

[0005] However, rare earth doped perovskite materials in the prior art still face challenges in terms of photostability and structural durability. Especially under environmental factors such as light, temperature changes, and electric fields, the optical properties of the materials are prone to degradation. In addition, the photochromic and photoluminescence response speeds of existing materials are slow, and the reversibility is poor, which limits their application in optical information storage and anti-counterfeiting encryption. Summary of the Invention

[0006] In view of this, the present invention provides a reversible photochromic luminescent material, which solves the technical problems of slow photochromic and photoluminescence response speeds and poor reversibility of existing materials.

[0007] To achieve the above object, the basic solution of the present invention provides a reversible photochromic luminescent material, which at least includes perovskite and a quantum dot doping material. The quantum dot doping material includes CsPbCl2Br and Yb 3+ : CsPbCl2Br quantum dots, where the molar ratio of element Yb: (Yb + Pb) is (1 - 25):100.

[0008] In a possible design, the molar ratio of element Yb: (Yb + Pb) is 12:100.

[0009] In a possible design, the molar ratio of element Yb: (Yb + Pb) is 1:100.

[0010] The present invention also provides a method for preparing the reversible photochromic luminescent material as described above, which at least includes the following steps

[0011] Step S1, synthesis of Cs - Oleate: Add Cs2CO3 to a mixture of octene and oleic acid, then heat to 200 °C until the white powder is completely dissolved, then keep the mixture at 130 °C for 1 hour and treat it under vacuum conditions to obtain Cs - Oleate;

[0012] Step S2, synthesis of Yb 3+ : CsPbCl2Br perovskite quantum dots: Prepare PbBr2, PbCl2, oleylamine, oleic acid, and octene. First, dissolve the rare earth chloride YbCl3 in octene, treat it at 160 °C for 1 hour and perform nitrogen purging, then add PbBr2 and PbCl2 to it. At the same time, lower the temperature to 120 °C and continue to treat for 1 hour. After complete dissolution, raise the temperature to 200 °C and continue nitrogen purging. Then, quickly inject the prepared Cs - Oleate into the mixture. After 10 seconds, immediately transfer it to an ice - water bath. Finally, centrifuge the sample at 5000 rpm for 10 minutes to remove the supernatant; resuspend the precipitate in toluene, centrifuge again at 12000 rpm for 10 minutes. The obtained quantum dots are redispersed in toluene and left to stand for 1 day. The final supernatant is colloidal Yb 3+ doped perovskite quantum dots.

[0013] In a possible design, in step S1, for every 0.8 g of Cs2CO3, 30 mL of octene and 2.5 mL of oleic acid are required.

[0014] In a possible design, in step S2, for every 0.5 mmol of PbBr2 and PbCl2, 1 mL of oleylamine, 1 mL of oleic acid, 10 mL of octene, and 1 mL of Cs - Oleate are corresponding.

[0015] The present invention also provides an optical anti-counterfeiting method based on the aforementioned reversible photochromic luminescent material, which at least includes the following steps:

[0016] Hiding step: Arrange CsPbCl2Br and Yb in the reversible photochromic luminescent material 3+ : The CsPbCl2Br quantum dots are arranged according to the anti-counterfeiting information, and under natural light irradiation, the anti-counterfeiting information is hidden;

[0017] Revealing step: When the reversible photochromic luminescent material is exposed to a xenon lamp or a continuous laser with a wavelength of 325 nm or 405 nm, the rare-earth doped quantum dots will undergo a change in the PL peak position through the photochromic effect, revealing the originally hidden anti-counterfeiting information.

[0018] The present invention also provides a luminescence method for the aforementioned reversible photochromic luminescent material, which at least includes the following steps: Using a xenon lamp or a continuous laser with a wavelength of 325 nm or 405 nm as the reaction light source to achieve a rapid photoluminescence response of the quantum dots.

[0019] The present invention also provides an application of the aforementioned luminescence method in optical anti-counterfeiting encryption.

[0020] The present invention also provides an application of the aforementioned reversible photochromic luminescent material in optical anti-counterfeiting encryption.

[0021] The working principle of the present invention is as follows:

[0022] 1. The PL (Photoluminescence) redshift caused by light irradiation mainly stems from the synergistic effect of halogen exchange and the funnel effect. Light irradiation excites electrons and holes in the material, promoting the exchange of halogen ions. In particular, the replacement of halogen Cl- by halogen Br- leads to lattice expansion and a decrease in the energy band width, thereby causing a redshift in the PL peak position. At the same time, the funnel effect enhances the non-radiative recombination process of excited-state carriers between multiple energy levels, enabling the carriers to transfer from higher energy levels to lower energy levels, further reducing the energy of photoluminescence and causing the PL emission wavelength to shift towards the long-wavelength direction, manifested as a redshift.

[0023] 2. After avoiding light, the process of the PL peak position returning to the original state involves the interaction of halogen exchange and the funnel effect. Halogen exchange is a reversible process. After avoiding light, the distribution of halogen ions gradually returns to the state before illumination, resulting in the lattice structure returning to its original state, thereby increasing the bandgap width and the PL peak position returning to the original position. The funnel effect is irreversible. It causes non-radiative recombination of excited-state carriers between energy levels, forming long-term energy loss. Therefore, the non-radiative recombination generated during illumination will persist for a long time after avoiding light, affecting the recovery process of PL. Therefore, the time required to avoid light is longer than the illumination time to completely eliminate the influence of the funnel effect and finally make the PL peak position return to the original state.

[0024] Compared with the prior art, the advantages of the present invention are as follows:

[0025] 1. Excellent photochromic and photoluminescence properties: Yb 3+ doping significantly improves the optical stability and photoluminescence properties of CsPbCl2Br quantum dots, especially showing significant photoluminescence peak shift and reversibility under illumination.

[0026] 2. Fast response and high reversibility: Using a 405 nm continuous laser as the reaction light source, rapid photoluminescence response of the quantum dots is achieved, and at least five reversible cycles are completed, significantly improving the efficiency of information encryption and anti-counterfeiting.

[0027] 3. Efficient optical anti-counterfeiting encryption system: Based on the combination of CsPbCl2Br and Yb 3+ : CsPbCl2Br quantum dots, a dual-mode digital encryption system is designed to achieve the concealment and selective display of information, significantly enhancing the anti-counterfeiting ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0029] Figure 1 FIG. Yb 3+ : CsPbCl2X (X = Br or I) quantum dots showing the peak position shift under light soaking, schematic diagram of the change in photoluminescence peak position;

[0030] Figure 2 FIGS. respectively show the physical and simulated diagrams of the anti-counterfeiting encryption system realized by using two kinds of quantum dots before and after doping in the embodiments of the present invention, where (Ⅰ) is the physical diagram and (Ⅱ) is the simulated diagram;

[0031] Figure 3 In the embodiment of the present invention, Yb 3+ : Cyclic test chart of CsPbCl2Br quantum dots under light soaking and light - free storage.

[0032] Figure 4 In the embodiment of the present invention, Yb 3+ : Schematic diagram of photoluminescence of reversible photochromic luminescent material of CsPbCl2Br quantum dots under continuous laser irradiation, where the molar ratio of Yb:(Yb + Pb) is 12:100. (a) is a partial PL spectrum diagram during the peak position shift, and (b) is a peak position shift diagram of the light soaking time at different wavelengths.

[0033] Figure 5 Schematic diagram of photoluminescence of the comparative example of the present invention under xenon lamp irradiation;

[0034] Figure 6 Schematic diagram of photoluminescence of Example 1 of the present invention under xenon lamp irradiation;

[0035] Figure 7 Schematic diagram of photoluminescence of Example 2 of the present invention under xenon lamp irradiation;

[0036] Figure 8 Schematic diagram of photoluminescence of Example 3 of the present invention under xenon lamp irradiation. Detailed implementation manners

[0037] To further illustrate each embodiment, the present invention provides accompanying drawings. These drawings are part of the disclosure of the present invention, mainly used to illustrate the embodiments, and can be used to explain the operating principle of the embodiments in combination with the relevant descriptions in the specification. With reference to these contents, those of ordinary skill in the art should be able to understand other possible implementation manners and the advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are usually used to represent similar components.

[0038] The basic solution of the present invention provides a reversible photochromic luminescent material, which at least includes perovskite and quantum dot doping material. The quantum dot doping material includes CsPbCl2Br and Yb 3+ : CsPbCl2Br quantum dots, where the molar ratio of element Yb:(Yb + Pb) is (1 - 25):100.

[0039] Preferably, the molar ratio of element Yb:(Yb + Pb) is 12:100 or the molar ratio of element Yb:(Yb + Pb) is 1:100.

[0040] In Example 1, the molar ratio of element Yb:(Yb + Pb) is 1:100.

[0041] Example 2, the difference from Example 1 is only that the molar ratio of element Yb:(Yb + Pb) is 12:100.

[0042] Example 3, the difference from Example 1 is only that the molar ratio of element Yb:(Yb + Pb) is 25:100.

[0043] Control example, the difference from Example 1 is only that the molar ratio of element Yb:(Yb + Pb) is 0:100.

[0044] As Figures 5-8 shown, when the molar ratio of element Yb:(Yb + Pb) is 0:100, that is, the ratio of the control example, no effective photoluminescence can be generated under xenon lamp irradiation. Only when the ratios in Examples 1, 2, and 3 are used, can effective photoluminescence be generated under xenon lamp irradiation.

[0045] As Figure 1 shown, the working principle of the present invention:

[0046] Ⅰ: The PL (Photoluminescence) redshift caused by light irradiation mainly stems from the synergistic effect of halogen exchange and the funnel effect. Light irradiation excites electrons and holes in the material, promoting the exchange of halogen ions. Especially when halogen Cl- is replaced by halogen Br-, it leads to lattice expansion and a decrease in the energy band width, thereby causing a redshift in the PL peak position. At the same time, the funnel effect enhances the non-radiative recombination process of excited-state carriers between multiple energy levels, enabling the carriers to transfer from higher energy levels to lower energy levels, further reducing the energy of photoluminescence and causing the PL emission wavelength to shift towards the long-wavelength direction, manifested as a redshift.

[0047] Ⅱ: After avoiding light, the process of the PL peak position returning to the original state involves the interaction between halogen exchange and the funnel effect. Halogen exchange is a reversible process. After avoiding light, the distribution of halogen ions gradually returns to the state before light irradiation, resulting in the lattice structure returning to its original state, thereby causing the energy band width to rise and the PL peak position to return to the original position. However, the funnel effect is irreversible. It causes non-radiative recombination of excited-state carriers between energy levels, forming long-term energy loss. Therefore, the non-radiative recombination generated during light irradiation will remain for a long time after avoiding light, affecting the recovery process of PL. Therefore, the time required to avoid light is longer than the time of light irradiation to completely eliminate the influence of the funnel effect and enable the PL peak position to finally return to the original state.

[0048] The present invention also provides a method for preparing the reversible photochromic luminescent material as described above, which at least includes the following steps,

[0049] ①Ⅰ: Synthesis of Cs - Oleate:

[0050] 0.8 g of Cs2CO3 was added to a mixture of 30 mL of octene and 2.5 mL of oleic acid, and then heated to 200 °C until the white powder was completely dissolved. Subsequently, the mixture was kept at 130 °C for 1 hour and treated under vacuum conditions.

[0051] Ⅱ: Yb 3+ : Synthesis of CsPbCl2Br perovskite quantum dots:

[0052] Prepare PbBr2 / PbCl2 (with a total amount of 0.5 mmol, and the specific ratio is adjusted according to the halogen element ratio of the prepared quantum dots), oleylamine (OAm, 1 mL), oleic acid (OA, 1 mL), and octene (ODE, 10 mL). First, dissolve rare earth chloride YbCl3 (calculated according to the expected doping concentration) in 10 mL of octene (ODE), treat it at 160 °C for 1 hour, and conduct nitrogen purging. Next, add PbBr2 and / PbCl2 to it, while the temperature is lowered to 120 °C and continue to treat for 1 hour. After complete dissolution, the temperature is raised to 200 °C and continue nitrogen purging. Then, quickly inject the prepared Cs-oleate (1 mL) into the mixture, and immediately transfer it to an ice-water bath after 10 seconds. Finally, the sample is centrifuged at 5000 rpm for 10 minutes to remove the supernatant. The precipitate is resuspended in toluene and centrifuged again at 12000 rpm for 10 minutes. The finally obtained quantum dots are redispersed in toluene and left standing for 1 day, and the finally obtained supernatant is colloidal Yb 3+ doped perovskite quantum dots. Since PbCl3 contains Cl element, on this basis, further optimize the actual ratio of PbCl2 to PbBr2 to ensure that the molar ratio of Cl:Br in the final drug is 2:1. The final reversible photochromic luminescent material requires mixing Yb 3+ : CsPbCl2Br and CsPbCl2Br together so that the molar ratio of element Yb: (Yb + Pb) is (1 - 25):100.

[0053] The present invention also provides an optical anti-counterfeiting method based on the aforementioned reversible photochromic luminescent material, which at least includes the following steps,

[0054] Hiding step: Arrange CsPbCl2Br and Yb 3+ : CsPbCl2Br quantum dots in the reversible photochromic luminescent material according to the anti-counterfeiting information. Under natural light irradiation, the anti-counterfeiting information is hidden;

[0055] Revealing step: When the reversible photochromic luminescent material is exposed to specific light, the rare earth-doped quantum dots will undergo a change in the PL peak position through the photochromic effect, revealing the originally hidden anti-counterfeiting information.

[0056] In terms of anti-counterfeiting, rare-earth-doped perovskite quantum dots can provide an efficient optical anti-counterfeiting solution through their unique photochromic properties. The implementation process of this solution is as follows:

[0057] Ⅰ: Information hiding: Under natural light irradiation, the sample (such as numbers, patterns or logos, composed of two kinds of quantum dots before and after doping) presents specific optical properties, and the anti-counterfeiting information is cleverly hidden in the sample, remaining low-key and difficult to detect.

[0058] Ⅱ: When the sample is exposed to a continuous laser with a wavelength of 405 nm, the rare-earth-doped quantum dots will change the PL peak position through the photochromic effect, thereby revealing the originally hidden anti-counterfeiting information.

[0059] In at least one embodiment, a xenon lamp or a continuous laser with a wavelength of 325 nm can also be used in the revealing step. If a xenon lamp is used, the reaction duration will be longer than that of a continuous laser with a wavelength of 325 nm or 405 nm. As Figure 4 、 Figure 7 shown, when the molar ratio of element Yb: (Yb + Pb) is certain, the effect of soaking with a xenon lamp is similar to that of soaking with a continuous laser, but the time is longer.

[0060] As Figure 4 shown, the present invention also provides a light-emitting method for the reversible photochromic luminescent material as described above, which at least includes the following steps: using a continuous laser with a wavelength of 405 nm as the reaction light source to achieve a rapid photoluminescence response of the quantum dots.

[0061] In at least one embodiment, a xenon lamp or a continuous laser with a wavelength of 325 nm or a xenon lamp is used as the reaction light source. If a xenon lamp is used, the reaction duration will be longer than that of a continuous laser with a wavelength of 325 nm or 405 nm.

[0062] The present invention also provides an application of the light-emitting method as described above in optical anti-counterfeiting encryption.

[0063] The present invention also provides an application of the reversible photochromic luminescent material as described above in optical anti-counterfeiting encryption.

[0064] Figure 2 Proved the application potential of the reversible photochromic luminescent material of the present invention in information hiding and display. Figure 3 Proved the high reversibility of the reversible photochromic luminescent material of the present invention. In summary, as Figures 1-3 shown, the innovations of the present invention are at least the following three points:

[0065] ① Yb 3+ Doping regulates the synergistic effect of halide ion migration and energy funnel effect

[0066] Technical problem: In existing rare-earth doped perovskite materials, the migration characteristics of halide ions are unstable under conditions such as light illumination, resulting in uncontrollable and poor reversibility of the change in the photoluminescence (PL) peak position, which limits their applications in optical information storage and anti-counterfeiting encryption.

[0067] Improvement point: Through doping with Yb 3+ doping, the migration characteristics of halide ions in CsPbCl2Br quantum dots under light illumination are effectively regulated, and a reversible shift of the photoluminescence peak is achieved. At the same time, the energy funnel effect is introduced to further enhance the non-radiative recombination process of excited-state carriers among multiple energy levels, enabling the carriers to transfer from higher energy levels to lower energy levels, resulting in a shift of the PL emission wavelength towards the long-wavelength direction (red shift). This synergistic effect not only improves the photochromic performance of the material but also achieves a rapid response and high reversibility of the PL peak position.

[0068] Advantages: Significantly improves the photo-stability and photoluminescence performance of the material. Especially under light illumination, it shows a significant PL peak shift and reversibility, providing a more reliable material basis for optical information storage and anti-counterfeiting encryption.

[0069] ② Fast response of photochromism and photoluminescence and optimization of the energy funnel effect

[0070] Technical problem: The response speeds of photochromism and photoluminescence of existing materials are slow and the reversibility is poor, making it difficult to meet the requirements of fast writing / reading and high-resolution information storage.

[0071] Improvement point: Using a 405 nm continuous laser as the reaction light source and combining with the optimization of the energy funnel effect, a rapid photoluminescence response of the quantum dots is achieved, and at least five reversible cycles are completed. By precisely controlling the doping concentration of Yb 3+ doping and the light illumination conditions, the energy funnel effect is further optimized, making the non-radiative recombination process of excited-state carriers more efficient, thereby achieving a rapid and stable change in the PL peak position.

[0072] Advantages: Significantly improves the efficiency of information encryption and anti-counterfeiting, achieves a rapid response and high reversibility, and meets the high requirements for material performance in optical information storage and anti-counterfeiting encryption.

[0073] ③ High-efficiency optical anti-counterfeiting encryption system based on the energy funnel effect

[0074] Technical problem: Existing optical anti-counterfeiting systems have deficiencies in the concealment and selectivity of information hiding and display, and it is difficult to provide a highly secure and difficult-to-replicate anti-counterfeiting solution.

[0075] Improvement point: Based on the combination of CsPbCl2Br and Yb 3+ : CsPbCl2Br quantum dots, a dual-mode digital encryption system is designed.

[0076] Using Yb 3+ By utilizing the change in the PL peak position of doped quantum dots under light illumination and the energy funnel effect, the concealment and selective display of information are achieved. Under natural light, the colors and brightness of the two types of quantum dots before and after doping are similar and difficult to distinguish, thus hiding the anti-counterfeiting information. Under specific light illumination conditions, the change in the PL peak position of the doped quantum dots reveals the hidden information, and this process is reversible.

[0077] Advantages: Significantly enhances the anti-counterfeiting ability, provides an efficient, concealed, and difficult-to-replicate optical anti-counterfeiting solution, and is applicable to high-security information storage and anti-counterfeiting encryption scenarios.

[0078] Although the above methods are illustrated and described as a series of actions for simplicity of explanation, it should be understood and appreciated that these methods are not limited by the order of the actions, because according to one or more embodiments, some actions may occur in a different order and / or concurrently with other actions that are illustrated and described herein or that are not illustrated and described herein but are understandable to those skilled in the art. Those skilled in the art will further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability of hardware and software, the various illustrative components, blocks, modules, circuits, and steps are described above in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the particular application and the design constraints imposed on the overall system. Skilled artisans may implement the described functionality in different ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention. The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein can be implemented using a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gates or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, battery compartment control board, micro battery compartment control board, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or

[0079] Multiple microprocessors, or any other such configuration. The steps of the methods or algorithms described in connection with the embodiments disclosed herein can be embodied directly in hardware, in software modules executed by a processor, or in a combination of the two. The software modules can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read from, and write to, the storage medium. In an alternative, the storage medium can be integrated into the processor. The processor and the storage medium can reside in an ASIC. The ASIC can reside in a user terminal. In an alternative, the processor and the storage medium can reside as discrete components in a user terminal. In one or more exemplary embodiments, the described functionality can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software as a computer program product, the functions can be stored on or transmitted via a computer-readable medium as one or more instructions or code. The computer-readable medium includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. The storage medium can be any available medium that can be accessed by a computer. By way of example and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a web site, a server computer, or other remote source using a coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of the medium. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray disc where disks typically reproduce data magnetically, while discs reproduce data optically with a laser. Combinations of the above should also be included within the scope of computer-readable media.

[0080] Although the methods above have been illustrated and described as a series of acts, it should be understood and appreciated that the methods are not limited by the order of acts, as some acts may occur in different orders and / or concurrently with other acts from those illustrated and described herein or not illustrated and described herein but understood by those skilled in the art, in accordance with one or more embodiments.

[0081] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments of equivalent changes within the scope of the technical solution of the present invention by using the technical content disclosed above. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A reversible photochromic luminescent material, characterized in that: At least including perovskite, quantum dot doping material, quantum dot doping material including CsPbCl2Br and Yb 3+ : CsPbCl2Br quantum dots, wherein the molar ratio of element Yb: (Yb+Pb) is (1-25):

100.

2. The reversible photochromic luminescent material according to claim 1, characterized in that: The molar ratio of the element Yb:(Yb+Pb) is 12:

100.

3. The reversible photochromic luminescent material according to claim 1, characterized in that: The molar ratio of the element Yb:(Yb+Pb) is 1:

100.

4. A method for preparing the reversible photochromic luminescent material according to any one of claims 1 to 3, characterized in that: At least the following steps are included: Step S1, synthesis of Cs-Oleate: Cs2CO3 is added to a mixture of octene and oleic acid, and then heated to 200°C until the white powder is completely dissolved, and then the mixture is kept at 130°C for 1 hour and treated under vacuum to obtain Cs-Oleate; Step S2, Yb 3+ :Synthesis of CsPbCl2Br perovskite quantum dots: Prepare PbBr2, PbCl2, oleylamine, oleic acid and octene. First, dissolve the rare earth chloride YbCl3 in octene, treat it at 160℃ for 1 hour, and purge it with nitrogen. Then, add PbBr2 and PbCl2. At the same time, the temperature was lowered to 120°C and the treatment was continued for 1 hour. After complete dissolution, the temperature was raised to 200°C and nitrogen purging was continued. Then, the prepared Cs-Oleate was quickly injected into the mixture and immediately transferred to an ice water bath after 10 seconds. Finally, the sample was centrifuged at 5000 rpm for 10 minutes and the supernatant was removed. The precipitate was resuspended in toluene and centrifuged again at 12000 rpm for 10 minutes. The obtained quantum dots were re-dispersed in toluene and left to stand for 1 day. The final supernatant was colloidal Yb 3+ Doped perovskite quantum dots.

5. The method for predicting the erosion wear rate in a natural gas gathering and transportation pipeline according to claim 4, characterized in that: In step S1, 30 mL of octene and 2.5 mL of oleic acid are required for every 0.8 g of Cs2CO3.

6. The method for predicting the erosion wear rate in a natural gas gathering and transportation pipeline according to claim 4 or 5, characterized in that: In step S2, every 0.5 mmol of PbBr2 and PbCl2 corresponds to 1 mL of oleylamine, 1 mL of oleic acid, 10 mL of octene and 1 mL of Cs-Oleate.

7. An optical anti-counterfeiting method based on the reversible photochromic luminescent material according to any one of claims 1 to 3, characterized in that: At least the following steps are included: Hiding step: Arrange CsPbCl2Br and Yb3+:CsPbCl2Br quantum dots in the reversible photochromic luminescent material according to the anti-counterfeiting information, and the anti-counterfeiting information is hidden under natural light; Revealing steps: When the reversible photochromic luminescent material is exposed to a xenon lamp or a continuous laser with a wavelength of 325nm or 405nm, the rare earth-doped quantum dots will change the PL peak position through the photochromic effect, revealing the originally hidden anti-counterfeiting information.

8. A light emitting method of the reversible photochromic luminescent material as claimed in claim 1, characterized in that: At least the following steps are included: A xenon lamp or a continuous laser with a wavelength of 325nm or 405nm is used as a reaction light source to achieve a fast photoluminescence response of the quantum dots.

9. An application of the luminescence method as claimed in claim 8 in optical anti-counterfeiting encryption.

10. Use of the reversible photochromic luminescent material according to any one of claims 1 to 3 in optical anti-counterfeiting encryption.

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