Multi-rare earth activated mechanical luminescent material based on Li (Nb, M) O3 solid solution as well as preparation method and application of multi-rare earth activated mechanical luminescent material

Abstract

The invention discloses a multi-rare earth activated mechanical luminescent material based on a Li (Nb, M) O3 solid solution as well as a preparation method and application thereof, and belongs to the technical field of luminescent materials. The chemical formula of the material is Li (Nb0. 7M0. 3) O3: xRe < 0.01 > Zn, wherein M is Ta or Sb, Re is Sm, Dy or Eu, and x is larger than or equal to 0.005 and smaller than 0.01. The multi-rare earth activated mechanical luminescent material is prepared from raw materials Li2CO3, Nb2O5, ZnO, M2O5 and rare earth oxide through drying, grinding, pre-sintering, secondary grinding and sieving. The material breaks through the activation limitation of single Pr < 3 + >, realizes multi-color adjustable luminescence from yellow light, orange red light to red light, is controllable in trap structure and energy band, is good in mechanical luminescence repeatability, and can recover the initial intensity after being excited by ultraviolet light. The material can be compounded with epoxy resin to form a mechanical luminescent composite material which is suitable for a stress distribution visualization device, an intelligent optical anti-counterfeiting device and a stress sensing device.

Description

Technical Field

[0001] This invention belongs to the field of luminescent materials technology, and particularly relates to a multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, its preparation method and application. Background Technology

[0002] Niobates (LiNbO3), as a typical class of multifunctional crystalline materials, possess significant application value in optoelectronics, sensing, and other fields due to their excellent piezoelectric, ferroelectric, and nonlinear optical properties. Among them, Pr... 3+ Doped niobate (LiNbO3∶Pr 3+ It was first reported as a mechanoluminescence (ML) material with zero threshold properties (Tu Dong, et al. Adv. Mater. 2017, 1606914.). This property greatly broadens the application scope of mechanoluminescence materials in the field of stress detection and significantly improves the detection accuracy, making niobate systems a core candidate direction for mechanoluminescence material research.

[0003] In recent years, Pr 3+ Niobate-based materials have attracted widespread attention from scientific research and industry due to their ability to stably generate visible light mechanoluminescence signals under mechanical stress. However, current research remains highly focused on Pr 3+ Niobate systems with a single activation center, while capable of emitting strong visible light mechanoluminescence signals, suffer from inherent drawbacks such as a single emission color and a fixed energy level structure; that is, their luminescence characteristics are limited by Pr. 3+ The electronic transition law makes it impossible to achieve multi-band emission modulation, which severely limits the performance tunability and application scope of niobate mechanoluminescence system (Xiuxia Yang, et al. Small 2021, 17, 2103441; Yang Hua, et al. Appl. Sci. 2024, 14, 2947.).

[0004] To overcome this technical bottleneck and further enrich the luminescent properties of the niobate system, Sm was introduced. 3+ Dy 3+ Eu 3+ Non-Pr 3+ Rare earth ions, as novel luminescent centers, have become a key research direction in the field. 3+ Rare earth ions possess unique and diverse 4f–4f electronic transition energy level structures, enabling them to emit multicolor light from yellow and orange to red under mechanical stimulation, providing core technological support for constructing a full-spectrum tunable mechanoluminescence system.

[0005] Therefore, development based on non-Pr 3+ Rare earth ion-activated niobate-based mechanoluminescent materials can not only break through the traditional Pr 3+ Overcoming the limitations of a single activation system, this approach enables the diversification of mechanoluminescent colors and the controllability of the spectrum. Furthermore, it provides a novel material system and theoretical foundation for emerging fields such as multifunctional displays, high-precision anti-counterfeiting identification, and dynamic stress visualization, which is of great significance for promoting the industrial application of mechanoluminescent materials. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, its preparation method, and its application.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A multi-rare-earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, with the chemical formula Li(Nb 0.7 M 0.3 O3∶xRe0.01Zn; where M is Ta or Sb, Re is Sm, Dy or Eu, and 0<x≤0.02, preferably 0.005≤x<0.01, more preferably x=0.005 or 0.01. This material exhibits significant yellow, orange-red, and red light emission under mechanical force, and demonstrates good recoverability and signal stability.

[0009] Furthermore, the raw materials for the multi-rare-earth activated mechanoluminescent material include Li₂CO₃, ZnO, M₂O₅, and rare-earth oxide Re₂O₃ with a purity of not less than 99.99%, where M is Ta or Sb, and Re is Sm, Dy, or Eu. This material is prepared using Li₂CO₃, ZnO, Nb₂O₅, M₂O₅, and rare-earth oxide Re₂O₃ with a purity greater than 99.99% via a high-temperature solid-state method.

[0010] This invention also provides a method for preparing multi-rare-earth activated mechanoluminescent materials based on Li(Nb,M)O3 solid solution, comprising the following steps:

[0011] Weigh the dried raw materials Li2CO3, Nb2O5, ZnO, M2O5 and Re2O3 and pour them into an agate mortar. Grind them with anhydrous ethanol as the grinding medium to obtain a uniformly mixed slurry.

[0012] The slurry is dried to obtain precursor powder;

[0013] The precursor powder was pre-calcined and naturally cooled to room temperature to obtain a well-crystallized Li(Nb,M)O3 solid solution. The cooled sintered block was then ground again to obtain a multi-rare earth activated mechanoluminescent material based on the Li(Nb,M)O3 solid solution.

[0014] Furthermore, the drying temperature of the raw material is 70-120℃, and the drying time is 4-6 hours.

[0015] Furthermore, the drying temperature of the slurry is 60-100℃, and the drying time is 10-20 min.

[0016] Furthermore, the specific operation steps of the pre-firing are as follows: heating to 1000-1200℃ at 2-5℃ / min in an air atmosphere, and pre-firing at this temperature for 4-10 hours.

[0017] Furthermore, the grinding time is 15-25 minutes; the re-grinding time is 5-10 minutes.

[0018] The present invention also provides a mechanoluminescent composite material, the raw materials of which include the multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution and resin.

[0019] Furthermore, the resin is an epoxy resin.

[0020] The present invention also provides an application of a mechanoluminescent composite material in stress distribution visualization devices, intelligent optical anti-counterfeiting devices, or stress sensor devices.

[0021] Compared with the prior art, the present invention has the following advantages and technical effects:

[0022] 1) The material prepared by this invention breaks through the limitations of single Pr 3+ Activating the limitations of niobate systems, traditional niobate mechanoluminescent materials mainly rely on Pr 3+ As a luminescent center, it emits a single wavelength. This invention is the first to realize Sm in a Li(Nb,M)O3 solid solution system. 3+ Dy 3+ Eu 3+ The effective activation by multiple rare earth ions expands the types of mechanoluminescent centers in niobate systems, enabling non-Pr 3+ Stable intercalation and efficient luminescence of rare earth ions in solid solution lattice.

[0023] 2) The materials prepared by this invention achieve diversification and tunability of mechanoluminescence colors. Through the energy level transition characteristics of different rare earth ions, the materials of this invention can achieve multi-color mechanoluminescence output from yellow light, orange-red light to red light. The regulation of M (Ta, Sb) elements in the solid solution further changes the trap energy level distribution, making the emission wavelength and intensity designable, providing a new material basis for realizing visualized stress imaging and multimodal display.

[0024] 3) The material prepared by this invention has good repeatability of mechanoluminescence properties. It can maintain stable and visible light output even after multiple mechanical loading cycles. Under the re-irradiation of 365nm ultraviolet light, the mechanoluminescence intensity can be restored to the initial state and can maintain repeatability for 10 cycles, showing excellent mechanical response stability and repeatability.

[0025] 4) The trap structure and band structure of the material prepared by this invention are controllable, and the Ta in the solid solution is... 5+ or Sb 5+ The introduction of [the technology] effectively modulates the crystal field at the B site, optimizes the depth distribution of carrier traps, thereby enhancing the synergistic effect of energy capture and release processes and improving the mechanical luminescence brightness and energy conversion efficiency.

[0026] 5) The preparation process of this invention is simple.

[0027] In summary, the preparation process of this invention is simple, and the prepared material introduces various non-Pr elements into the Li(Nb,M)O3 solid solution system. 3+ Rare earth ions enable the diversification and tunability of mechanoluminescence colors, significantly expanding the types and performance boundaries of luminescent centers in niobate systems. They can be used in fields such as stress distribution visualization monitoring, intelligent anti-counterfeiting, or stress sensing. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0029] Figure 1 The XRD patterns of the multi-rare-earth activated mechanoluminescent materials prepared in Examples 1-3 are shown below.

[0030] Figure 2 The image shows the mechanoluminescence spectrum of the mechanoluminescent composite material prepared in Example 1 under a mechanical force of 30 N.

[0031] Figure 3 The mechanical light emission curves of the mechanoluminescent composite material prepared in Example 1 after 60 s of 365 nm ultraviolet light irradiation are shown for 11 consecutive cycles.

[0032] Figure 4 The mechanical luminescence curves of the mechanoluminescent composite material prepared in Example 1 were obtained by irradiating it with 365nm ultraviolet light for 60s before each test, and were obtained for 10 cycles.

[0033] Figure 5 The image of the luminescent composite material prepared in Example 1 after writing the letter "S" with a glass rod;

[0034] Figure 6 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 2 under a mechanical force of 30 N.

[0035] Figure 7 The image of the luminescent composite material prepared in Example 2 after writing the letter "D" with a glass rod;

[0036] Figure 8 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 3 under a mechanical force of 30 N.

[0037] Figure 9 The XRD patterns of the multi-rare-earth activated mechanoluminescent materials prepared in Examples 4-5 are shown.

[0038] Figure 10 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 4 under a mechanical force of 30 N.

[0039] Figure 11 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 5 under a mechanical force of 30 N.

[0040] Figure 12 The image shows the XRD pattern of the materials prepared in Comparative Examples 1-2. Detailed Implementation

[0041] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0042] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0043] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0044] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0045] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0046] This invention provides a multi-rare-earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, with the chemical formula Li(Nb... 0.7 M 0.3 O3∶xRe0.01Zn; where M is Ta or Sb, and Re is Sm 3+ Dy 3+ Or Eu 3+ Where 0 < x ≤ 0.02, preferably 0.005 ≤ x < 0.01, and more preferably x = 0.005 or 0.01. This material is prepared by a high-temperature solid-state method using Li2CO3, ZnO, M2O5 and rare earth oxide Re2O3 with a purity greater than 99.99% as raw materials.

[0047] The preparation method of the multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution includes the following steps:

[0048] I. Preparations before the experiment

[0049] 1. Select Li₂CO₃, Nb₂O₅, ZnO, M₂O₅ (M = Ta or Sb) and rare earth oxide Re₂O₃ (Re corresponds to Sm) with a purity of not less than 99.99%. 3+ Dy 3+ Or Eu 3+ The raw materials are Re2O3 (i.e., Sm2O3, Dy2O3, or Eu2O3). All the above raw materials are placed in an oven at 70-120℃ (e.g., 70℃) and dried for 4-6 hours (e.g., 4 hours) to remove the adsorbed moisture and ensure the purity of the subsequent reaction.

[0050] 2. Based on the chemical formula of the target material, Li(Nb) 0.7 M 0.3 O3∶xRe0.01Zn (M is Ta or Sb, Re is Sm) 3+ Dy 3+ Or Eu 3+ The mass fractions of each component corresponding to the values ​​of 0 < x ≤ 0.02, preferably 0.005 ≤ x < 0.01, and more preferably x = 0.005 or 0.01, are accurately weighed using a weighing instrument (such as an electronic analytical balance) that meets the experimental requirements.

[0051] II. Preparation of Mechatronic Materials

[0052] 1. Grinding and mixing raw materials: Pour all the weighed raw materials into an agate mortar, add an appropriate amount of anhydrous ethanol as the grinding medium, and grind manually or with the help of grinding equipment for 15-25 minutes (e.g., 20 minutes). Stir constantly during the process to ensure that the raw materials are fully mixed and finally form a uniform and fine slurry.

[0053] 2. Precursor preparation by drying slurry: Transfer the well-mixed slurry to a clean drying container and place it in an oven at 60-100℃ (e.g., 70℃) for 10-20 minutes (e.g., 15 minutes) until the anhydrous ethanol in the slurry is completely evaporated, resulting in a dry and loose precursor powder.

[0054] 3. Precursor pre-calcination: The precursor powder is loaded into a high-temperature resistant crucible (such as an alumina crucible) and placed in a muffle furnace. The muffle furnace parameters are set, and the temperature is increased to 1000-1200℃ (such as 1080℃) at a heating rate of 2-5℃ / min (such as 5℃ / min) under air atmosphere. After reaching the target temperature, it is held for 4-10h (such as 8h) for pre-calcination to allow the precursor to react fully and crystallize. After pre-calcination, the muffle furnace is turned off, and the crucible is allowed to cool naturally to room temperature with the furnace to obtain a well-crystallized Li(Nb,M)O3 solid solution sintered block.

[0055] 4. Grinding and sieving to obtain the finished product: Take out the cooled Li(Nb,M)O3 solid solution sintered block and put it into an agate mortar for secondary grinding. The grinding time is controlled at 5-10 minutes (e.g., 10 minutes) to crush the sintered block into uniform powder, and finally obtain the multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution.

[0056] III. Preparation of Mechatronic Composite Materials

[0057] 1. Resin mixing: Measure epoxy resin A and epoxy resin B (such as TJ2221A and TJ 2221B) in a clean beaker at a mass ratio of 3:1. Stir thoroughly with a glass rod for 5-10 minutes until the two resins are completely mixed and homogeneous to form an epoxy resin mixture.

[0058] 2. Material composite: Weigh out the multi-rare earth activated mechanoluminescent material powder prepared above (e.g., 2g), spread it evenly on the bottom of a polytetrafluoroethylene mold (e.g., a cylindrical mold with an inner diameter of 25mm), and gently press it to make the powder adhere to the mold; slowly pour the prepared epoxy resin mixture into the mold to cover the mechanoluminescent material powder, and let it stand at room temperature for 5 minutes until all the air bubbles in the mold have escaped.

[0059] 3. Curing and molding: Place the mold after standing in an oven at 60℃ and keep it at that temperature for 6 hours to allow the epoxy resin to fully cure. After curing, remove the mold and demold to obtain a multi-rare earth activated mechanoluminescent composite material based on Li(Nb,M)O3 solid solution.

[0060] Unless otherwise specified, "room temperature" in this invention refers to 25±2℃.

[0061] All raw materials used in this invention were purchased from the market.

[0062] The technical solution of the present invention will be further illustrated by the following embodiments.

[0063] Example 1

[0064] A Li(Nb) 0.7 Ta 0.3 The preparation steps of O3∶0.005Sm0.01Zn are as follows:

[0065] 1) The raw materials Li2CO3 (purity 99.99%), Nb2O5 (purity 99.99%), Ta2O5 (purity 99.99%), Sm2O3 (purity 99.99%) and ZnO (purity 99.99%) were all dried in an oven at 70℃ for 4 hours;

[0066] 2) According to the chemical formula Li(Nb) 0.7 Ta 0.3 To determine the required mass fraction of O3:0.005Sm0.01Zn, accurately weigh the raw materials and place them in an agate mortar. Grind them for 20 minutes using anhydrous ethanol as the medium. Then, place the well-mixed raw materials in a 70°C oven and dry them for 15 minutes.

[0067] 3) The dried product is heated to 1080℃ in air at a rate of 5℃ / min and sintered at this temperature for 8 hours. After naturally cooling to room temperature, it is ground again for 10 minutes to obtain a multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution.

[0068] Figure 1 The image shows the XRD pattern of the multi-rare-earth activated mechanoluminescent material prepared in Example 1. Figure 1 As can be seen from the data, the Li(Nb) prepared in Example 1... 0.7 Ta 0.3 The Li(NbO3)0.005Sm0.01Zn phase is a pure phase, matching the standard cards (LiNbO3PDF#20-0631 and LiTaO3PDF#29-0836), and no impurity phases or additional diffraction peaks were detected, proving that Li(NbO3)0.005Sm0.01Zn is a pure phase. 0.7 Ta 0.3 O3∶0.005Sm0.01Zn was successfully prepared.

[0069] Application Example 1

[0070] The preparation steps of a mechanoluminescent composite material are as follows:

[0071] S1. Measure 3g of epoxy resin A (TJ 2221A, Truly (Suzhou) Materials Technology Co., Ltd.) and 1g of epoxy resin B (TJ 2221B, Truly (Suzhou) Materials Technology Co., Ltd.) and pour them into a clean beaker. Stir thoroughly with a glass rod until the two resin solutions are completely mixed and homogeneous to form an epoxy resin mixture.

[0072] S2. Weigh 2g of the rare earth activated mechanoluminescent material prepared in Example 1 and spread it evenly on the bottom of a polytetrafluoroethylene mold (a cylindrical mold with an inner diameter of 25mm). Gently press the powder to make it adhere to the mold.

[0073] S3. Slowly pour the epoxy resin mixture prepared in step S1 into the mold to cover the multi-rare earth activated mechanoluminescent material, and let it stand at room temperature for 5 minutes to allow all air bubbles in the mold to escape.

[0074] S4. Place the settled material in a 60℃ oven for 6 hours, then demold to obtain the bulk mechanoluminescent composite material.

[0075] Performance testing:

[0076] 1. To demonstrate the effectiveness of the Li(Nb) prepared in Example 1 0.7 Ta 0.3 O3∶0.005Sm0.01Zn exhibits mechanoluminescence properties, and mechanoluminescence spectrum testing was conducted. The test results are as follows: Figure 2As shown, it can be observed that the bulk mechanoluminescent composite material prepared in Example 1 exhibits Sm under the application of a mechanical force of 30N. 3+ The material exhibits characteristic emission bands, with the strongest emission bands at 576 nm and 614 nm. Test results show that the material prepared using Example 1 of this invention displays a bright orange-red mechanoluminescence signal.

[0077] 2. To demonstrate the effectiveness of the Li(Nb) prepared in Example 1 0.7 Ta 0.3 The mechanoluminescence properties of O3∶0.005Sm0.01Zn were repeatable, and mechanoluminescence cycle stability tests were conducted. Before testing, the bulk mechanoluminescent composite material prepared in Example 1 was irradiated with 365nm ultraviolet light once every 60 seconds, and a mechanical force of 30N was applied. The mechanoluminescence spectrum was continuously measured for 11 cycles, and its mechanoluminescence intensity variation curve is shown below. Figure 3 As shown. Furthermore, before each test, the sample was irradiated with 365nm ultraviolet light for 60 seconds, and a mechanical force of 30N was applied. The mechanoluminescence spectrum was measured continuously for 10 cycles, and the changes in mechanoluminescence intensity are shown below. Figure 4 As shown in the figure. The test results show that under 10 consecutive test cycles, the mechanoluminescence intensity shows a gradual decreasing trend, but the mechanoluminescence signal can still be clearly detected; when the material is irradiated with 365nm ultraviolet light again before each test, the mechanoluminescence intensity can be restored to the initial value. The material of this invention exhibits good repeatability of mechanoluminescence performance.

[0078] 3. The Li(Nb) prepared in Example 1 of this invention. 0.7 Ta 0.3 After the O3∶0.005Sm0.01Zn material was composited with epoxy resin, an "S" image was written on the surface of the composite sample using a glass rod. The resulting luminescent image is shown below. Figure 5 As shown, this demonstrates its value as a material for stress distribution visualization or intelligent anti-counterfeiting.

[0079] Example 2

[0080] A Li(Nb) 0.7 Ta 0.3 The preparation of Sm2O3:0.01Dy0.01Zn was carried out using the same method as in Example 1, except that Sm2O3 was replaced with Dy2O3, and the amount was adjusted according to the chemical formula. This yielded a multi-rare-earth activated mechanoluminescent material based on the Li(Nb,M)O3 solid solution, namely Li(Nb... 0.7 Ta 0.3 )O3∶0.01Dy0.01Zn.

[0081] Figure 1The image shows the XRD pattern of the multi-rare-earth activated mechanoluminescent material prepared in Example 2. Figure 1 It can be seen from this that Li(Nb) 0.7 Ta 0.3 O3∶0.01Dy0.01Zn was successfully prepared.

[0082] Application Example 2

[0083] Similar to Application Example 1, except that the multi-rare earth activated mechanoluminescent material prepared in Example 1 is replaced by the multi-rare earth activated mechanoluminescent material prepared in Example 2 with the same mass.

[0084] Performance testing:

[0085] Figure 6 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 2 under a mechanical force of 30 N. As can be seen from the image, the bulk mechanoluminescent composite material prepared in Example 2 exhibits Dy... 3+ The material exhibits characteristic emission bands, with the strongest emission bands at 490 nm and 580 nm. Test results show that the material prepared using Example 2 displays a distinct yellow mechanoluminescence signal.

[0086] Figure 7 The image shows the luminescent image of the mechanoluminescent composite material prepared in Example 2 after the letter "D" was written on it with a glass rod. This image demonstrates the value of the material prepared in Example 2 as a stress distribution visualization material or a smart anti-counterfeiting material.

[0087] Example 3

[0088] A Li(Nb) 0.7 Ta 0.3 The preparation of Sm2O3:0.01Eu0.01Zn was carried out using the same method as in Example 1, except that Sm2O3 was replaced with Eu2O3, and the amount was adjusted according to the chemical formula. This yielded a multi-rare-earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, namely Li(Nb... 0.7 Ta 0.3 )O3∶0.01Eu0.01Zn.

[0089] Figure 1 The image shows the XRD pattern of the multi-rare-earth activated mechanoluminescent material prepared in Example 3. Figure 1 It can be seen from this that Li(Nb) 0.7 Ta 0.3 O3∶0.01Eu0.01Zn was successfully prepared.

[0090] Application Example 3

[0091] Similar to Application Example 1, except that the multi-rare earth activated mechanoluminescent material prepared in Example 1 is replaced with the multi-rare earth activated mechanoluminescent material prepared in Example 3 by the same mass.

[0092] Figure 8 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 3 under a mechanical force of 30 N. As can be seen from the image, the bulk mechanoluminescent composite material prepared in Example 3 exhibits Eu luminescence under a mechanical force of 30 N. 3+ The material exhibits a characteristic emission band, with the strongest emission band at 617 nm. Test results show that the material prepared using Example 3 displays a distinct red mechanoluminescence signal.

[0093] Example 4

[0094] A Li(Nb) 0.7 Sb 0.3 The preparation method of Li(Nb,M)O3∶0.005Sm0.01Zn is the same as in Example 1, except that the raw material Ta is replaced with Sb to prepare a multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, namely Li(Nb 0.7 Sb 0.3 O3∶0.005Sm0.01Zn.

[0095] Application Example 4

[0096] Similar to Application Example 1, except that the multi-rare earth activated mechanoluminescent material prepared in Example 1 is replaced with the multi-rare earth activated mechanoluminescent material prepared in Example 4 by the same mass.

[0097] Figure 9 The image shows the XRD pattern of the multi-rare-earth activated mechanoluminescent material prepared in Example 4. Figure 9 It can be seen from this that Li(Nb) 0.7 Sb 0.3 O3∶0.005Sm0.01Zn was successfully prepared.

[0098] Figure 10 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 4 under a mechanical force of 30 N. As can be seen from the image, the bulk mechanoluminescent composite material prepared in Example 4 exhibits Sm... 3+ The material exhibits characteristic emission bands, with the strongest emission bands at 576 nm, 617 nm, and 656 nm. Test results show that the material prepared using Example 4 exhibits a distinct orange-red mechanoluminescence signal.

[0099] Example 5

[0100] A Li(Nb) 0.7Sb 0.3 The preparation method of Li(Nb,M)O3∶0.01Dy0.01Zn is the same as in Example 2, except that the raw material Ta is replaced with Sb to prepare a multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, namely Li(Nb 0.7 Sb 0.3 )O3∶0.01Dy0.01Zn.

[0101] Application Example 5

[0102] Similar to Application Example 1, except that the multi-rare earth activated mechanoluminescent material prepared in Example 1 is replaced with the multi-rare earth activated mechanoluminescent material prepared in Example 5 by the same mass.

[0103] Figure 9 The image shows the XRD pattern of the multi-rare-earth activated mechanoluminescent material prepared in Example 5. Figure 9 It can be seen from this that Li(Nb) 0.7 Sb 0.3 O3∶0.01Dy0.01Zn was successfully prepared.

[0104] Figure 11 The image shows the mechanoluminescence spectrum of the bulk mechanoluminescent composite material prepared in Example 5 under a mechanical force of 30 N. As can be seen from the image, the bulk mechanoluminescent composite material prepared in Example 5 exhibits Dy... 3+ The material exhibits a characteristic emission band, with the strongest emission band at 581 nm. Test results show that the material prepared using Example 5 displays a distinct yellow mechanoluminescence signal.

[0105] Comparative Example 1

[0106] The preparation method of LiNbO3∶0.005Sm0.01Zn is the same as in Example 1, except that Ta2O5 is not added and the amount is adjusted according to the chemical formula to obtain LiNbO3∶0.005Sm0.01Zn.

[0107] Figure 12 The XRD pattern of the material prepared in Comparative Example 1 is shown below. Figure 12 As can be seen, LiNbO3∶0.005Sm0.01Zn was successfully prepared.

[0108] Comparative Application Example 1

[0109] Same as Example 1, except that the multi-rare earth activated mechanoluminescent material prepared in Example 1 is replaced by the material prepared in Comparative Example 1 in equal mass.

[0110] Mechanoluminescence spectroscopy was performed on the composite material prepared in Comparative Application Example 1. No mechanoluminescence signal was detected under the application of a mechanical force of 30 N.

[0111] Comparative Example 2

[0112] The preparation method of LiNbO3∶0.01Eu0.01Zn is the same as in Example 3, except that Ta2O5 is not added and the amount is adjusted according to the chemical formula to obtain LiNbO3∶0.01Eu0.01Zn.

[0113] Figure 12 The XRD pattern of the material prepared in Comparative Example 2 is shown below. Figure 12 As can be seen, LiNbO3∶0.01Eu0.01Zn was successfully prepared.

[0114] Comparative Application Example 2

[0115] Same as Example 1, except that the multi-rare earth activated mechanoluminescent material prepared in Example 1 is replaced by the material prepared in Comparative Example 2 in equal mass.

[0116] Mechanoluminescence spectroscopy was performed on the composite material prepared in Comparative Application Example 2. No mechanoluminescence signal was detected under the application of a mechanical force of 30 N.

[0117] Performance tests of the samples prepared in the above examples and comparative examples revealed that the sample prepared in Example 1 exhibited the strongest mechanoluminescence brightness, good repeatability and cyclic stability, and the mechanoluminescence signal remained clearly detectable even after 10 consecutive cycles of testing. Under 365nm ultraviolet pre-excitation, the sample recovered to its initial intensity after 10 cycles of mechanical force loading. The samples prepared in Examples 2-5 all showed detectable mechanoluminescence signals. Therefore, the preferred value is 0.005 ≤ x < 0.02, and the most preferred value is x = 0.005 and 0.01.

[0118] The Li(Nb) prepared by this invention 0.7 M 0.3 The O3:xRe0.01Zn series of mechanoluminescent materials all exhibit significant mechanoluminescent properties. Under external force stimulation (such as a 30N mechanical load), Li(Nb) 0.7 Ta 0.3 O3∶0.01Dy0.01Zn、Li(Nb) 0.7 Ta 0.3 O3∶0.005Sm0.01Zn、Li(Nb) 0.7 Ta 0.3 O3∶0.01Eu0.01Zn、Li(Nb) 0.7 Sb 0.3O3∶0.01Dy0.01Zn and Li(Nb) 0.7 Sb 0.3 The O3∶0.005Sm0.01Zn samples all showed obvious mechanoluminescence emission signals, indicating that the introduced non-Pr 3+ Rare earth ions can effectively serve as mechanoluminescent activation centers in the Li(Nb,M)O3 solid solution system. Among them, Li(Nb... 0.7 Ta 0.3 The O3∶0.005Sm0.01Zn sample consistently produced repeatable mechanoluminescence signals during 10 consecutive mechanical loading cycles, exhibiting minimal changes in emission intensity and demonstrating excellent mechanical response stability and structural reproducibility. This indicates that the non-Pr... 3+ Rare earth activated Li(Nb,M)O3 solid solution materials can achieve multi-color tunable luminescence, have good mechanoluminescence recoverability and repeatability, and can maintain stable luminescence output under multiple external forces. They are suitable for fields such as stress visualization monitoring, dynamic anti-counterfeiting and mechanical sensing.

[0119] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A multi-rare-earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution, characterized in that, The chemical formula is Li(Nb) 0.7 M 0.3 O3∶xRe0.01Zn; where M is Ta or Sb, Re is Sm, Dy or Eu, and 0.005≤x<0.

01.

2. The multi-rare-earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution according to claim 1, characterized in that, The raw materials for the multi-rare earth activated mechanoluminescent material include Li2CO3, Nb2O5, ZnO, M2O5 and rare earth oxide Re2O3 with a purity of not less than 99.99%.

3. A method for preparing a multi-rare-earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution as described in claim 1 or 2, characterized in that, Includes the following steps: Weigh the dried raw materials Li2CO3, Nb2O5, ZnO, M2O5 and Re2O3, and grind them with anhydrous ethanol as the grinding medium to obtain a slurry; The slurry is dried to obtain precursor powder; The precursor powder was pre-calcined, naturally cooled to room temperature, and then ground again to obtain a multi-rare earth activated mechanoluminescent material based on Li(Nb,M)O3 solid solution.

4. The preparation method according to claim 3, characterized in that, The drying temperature of the raw material is 70-120℃, and the drying time is 4-6 hours.

5. The preparation method according to claim 3, characterized in that, The drying temperature of the slurry is 60-100℃, and the drying time is 10-20 minutes.

6. The preparation method according to claim 3, characterized in that, The specific steps for pre-firing are as follows: heat the temperature to 1000-1200℃ at a rate of 2-5℃ / min in air atmosphere, and pre-firing at this temperature for 4-10 hours.

7. The preparation method according to claim 3, characterized in that, The grinding time is 15-25 minutes; the re-grinding time is 5-10 minutes.

8. A mechanoluminescent composite material, characterized in that, The raw materials include the multi-rare earth activated mechanoluminescent material and resin based on Li(Nb,M)O3 solid solution as described in any one of claims 1 or 2.

9. The mechanoluminescent composite material according to claim 8, characterized in that, The resin is epoxy resin.

10. The application of a mechanoluminescent composite material as described in claim 8 or 9 in a stress distribution visualization device, an intelligent optical anti-counterfeiting device, or a stress sensor device.

Images