Rare earth terbium metal organic complex stress luminescent material as well as preparation method and application thereof

Abstract

The invention discloses a rare earth terbium metal organic complex stress luminescent material as well as a preparation method and application thereof, and belongs to the technical field of stress luminescent materials. The preparation method of the rare earth terbium metal organic complex stress luminescent material comprises the following steps: mixing Trap TMS, THF and terbium salt, and preparing the rare earth terbium metal organic complex stress luminescent material through a solvent evaporation method. The rare earth terbium metal organic complex stress luminescent material disclosed by the invention is excellent in stress luminescent property, a strong green luminescence phenomenon can be observed under a dark condition, and the rare earth terbium metal organic complex stress luminescent material also has bright green luminescence visible to naked eyes under bright natural light; in addition, the rare earth terbium metal organic complex stress luminescent material disclosed by the invention also has very strong photoluminescence performance.

Description

Technical Field

[0001] The present invention relates to the technical field of stress luminescent materials, and particularly to a rare earth terbium metal-organic complex stress luminescent material, a preparation method thereof, and an application thereof. Background Art

[0002] Stress luminescence (ML) materials are materials that exhibit luminescence when stimulated by stress. The modes of stress stimulation include, but are not limited to, various forms such as extrusion, grinding, friction, impact, and ultrasonic waves, involving the conversion of mechanical energy into visible light. In recent years, a variety of inorganic and organic stress luminescent compounds have been successfully prepared and shown great application prospects in the fields of real-time stress sensors, signature graphics, displays, structural damage monitoring, wearable lighting devices, self-powered displays, mechanical energy collection and conversion, and bioimaging devices.

[0003] Currently reported stress luminescent materials include three categories: organic, inorganic, and organic-inorganic hybrid materials. These stress luminescent materials have the following problems: (1) The poor luminescence performance of stress luminescent powders is caused by their own structural problems, and there are few stress luminescent materials with strong luminescence brightness at room temperature; (2) The preparation conditions of inorganic stress luminescent materials are usually relatively harsh, requiring anhydrous and anaerobic conditions and the reaction temperature is usually several hundred or even thousands of degrees Celsius, with problems such as long reaction time, high reaction energy consumption, high equipment requirements, and high costs, which limit the large-scale production of such materials.

[0004] In summary, the types of materials with relatively high stress luminescence intensity are still relatively few at present, and the preparation conditions are relatively harsh. Therefore, it is very necessary to develop new high-strength stress luminescent materials with simple preparation methods. Summary of the Invention

[0005] The purpose of the present invention is to provide a rare earth terbium metal-organic complex stress luminescent material, a preparation method thereof, and an application thereof to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above purpose, the present invention provides the following solutions:

[0007] One of the technical solutions of the present invention: A rare earth terbium metal-organic complex stress luminescent material, with a structural general formula of [(X)Tb(THF)]; the chemical formula is C 34 H 53 TbN4OSi3;

[0008] Wherein, X is

[0009] The unit cell parameters are α = 90°, β = 101°, γ = 90°.

[0010] In the rare earth terbium metal-organic complex stress luminescent material, X is the main ligand and THF (tetrahydrofuran) is the auxiliary ligand; Tb in the rare earth terbium metal-organic complex stress luminescent material is in the +3 valence state.

[0011] The rare earth terbium metal-organic complex stress luminescent material prepared by the present invention has stress luminescence performance, can produce bright green light through mechanical force stimulation, thereby realizing the visual transformation of force-light, and the rare earth terbium metal-organic complex stress luminescent material prepared by the present invention has photoluminescence performance.

[0012] The second technical solution of the present invention: A preparation method of the above-mentioned rare earth terbium metal-organic complex stress luminescent material, comprising the following steps:

[0013] Mix Trapen TMS , THF (tetrahydrofuran, dried pure solvent) and terbium salt, and prepare the rare earth terbium metal-organic complex stress luminescent material by solvent evaporation method;

[0014] The structural formula of the Trapen TMS is: Wherein, TMS is trimethylsilyl.

[0015] The preparation method of the rare earth terbium metal-organic complex stress luminescent material, comprising the following steps:

[0016] Mix Trapen TMS , THF and terbium salt, stir and react, then remove THF, extract with toluene, filter, dry the filtrate, dissolve with THF, add hexane, and let stand at low temperature to obtain the rare earth terbium metal-organic complex stress luminescent material.

[0017] Furthermore, the preparation method of the rare earth terbium metal-organic complex stress luminescent material, comprising the following steps:

[0018] Add terbium salt to THF and stir to dissolve to obtain a terbium salt solution;

[0019] Then drop the solution of Trapen TMS into the terbium salt solution, stir and react, then remove THF, extract with toluene, filter, dry the filtrate, dissolve with THF, add hexane, and let stand at low temperature to obtain the rare earth terbium metal-organic complex stress luminescent material.

[0020] Furthermore, the temperature of the stirring and dissolving is room temperature (20 - 30 °C), and the time is 10 min; the purpose of stirring is to dissolve the terbium salt better; the temperature of the stirring reaction is room temperature (20 - 30 °C).

[0021] Further, the terbium salt includes terbium chloride (TbCl3).

[0022] Further, the time of the stirring reaction is 12 - 15 h.

[0023] Further, the temperature of the low - temperature standing is - 30°C, and the time is ≥14 days.

[0024] The purpose of standing at low temperature is to slowly volatilize the solvent.

[0025] Further, the molar ratio of Trapen TMS and the terbium salt is 1:1.5.

[0026] Further, the dosage ratio of Trapen TMS in the Trapen solution TMS and THF is 0.2 mmol:20 mL.

[0027] The third technical solution of the present invention: An application of the above - mentioned rare - earth terbium metal - organic complex stress - luminescence material in the field of intelligent sensing.

[0028] Furthermore, the field of intelligent sensing includes visual pressure sensing, intelligent anti - counterfeiting, electronic signature, flexible wearable sensing devices or the field of biomedicine.

[0029] Furthermore, the method of the application includes:

[0030] Compound the rare - earth terbium metal - organic complex stress - luminescence material with an organic polymer material to prepare a transparent composite film;

[0031] Attach the composite film to the surface of the component to be measured, apply mechanical external force, and convert the stress received by the component to be measured into light emission under the action of the mechanical external force.

[0032] Through the above process, high - brightness stress - light direct energy conversion can be realized, and applications in the fields of visual pressure sensing, intelligent anti - counterfeiting, electronic signature, flexible wearable sensing devices or biomedicine can be achieved.

[0033] Furthermore, the organic polymer material includes polyethylene terephthalate (PET) or polydimethylsiloxane (PDMS).

[0034] The present invention discloses the following technical effects:

[0035] (1) The stress luminescence property of the rare earth terbium metal-organic complex stress luminescence material of the present invention is excellent. Not only can a strong green luminescence phenomenon be observed under dark conditions, but also a visible bright green luminescence can be seen under bright natural light. Moreover, the rare earth terbium metal-organic complex stress luminescence material of the present invention also has strong photoluminescence properties.

[0036] (2) The rare earth terbium metal-organic complex stress luminescence material of the present invention uses the Trapen TMS ligand as a raw material. This Trapen TMS ligand can effectively sensitize the luminescence of the central Tb(III) ion through the "antenna effect" (since rare earth ions have a weak absorption ability for light, they do not have a high luminescence intensity. When rare earth ions combine with organic ligands to form rare earth complexes, because their ligands can strongly absorb energy in the ultraviolet region and transfer the energy to the central rare earth ions through intramolecular or intermolecular means, thus efficiently enhancing the characteristic emission of the central rare earth ions. This process is called the "antenna effect"). As a result, the material can emit a strong narrow-band green light emission without light illumination, only under the action of stress, realizing the visual transformation of force-light. The stress luminescence peak is located near 547 nm.

[0037] (3) For the rare earth terbium metal-organic complex stress luminescence material of the present invention, within a certain range, the stress luminescence intensity of the material is proportional to the magnitude of the applied mechanical force, enabling the visualization of pressure sensing and can be applied to various intelligent sensing fields, such as visual pressure sensing, intelligent anti-counterfeiting, electronic signature, flexible wearable sensing devices, or biomedical fields.

[0038] (4) The preparation method of the rare earth terbium metal-organic complex stress luminescence material of the present invention is compared with the traditional high-temperature solid-phase preparation method (the high-temperature solid-phase preparation method is an inorganic material synthesis method based on solid-state reactions. Its principle is to promote the diffusion and migration of atoms or ions in solid raw materials through high temperature (usually several hundred to thousands of degrees Celsius), and chemical reactions occur and nucleate and grow gradually at the particle interface, ultimately forming a target product with high crystallinity (such as ceramics, battery materials, or fluorescent materials). The synthesis process mainly includes the stoichiometric mixing of raw material powders, pressing to enhance particle contact, and high-temperature calcination and subsequent cooling treatment. The advantages of this method are simple process, no solvent required, stable product structure, and suitable for large-scale production, but it has disadvantages such as high energy consumption, slow reaction rate, large product particle size, and uneven morphology) in that the preparation method is simple, the conditions are mild and easy to control, the reaction energy consumption is low, it is environmentally friendly and pollution-free, and the material yield is high, the purity is high, and it is easy to industrialize production and practical application. Brief Description of the Drawings

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0040] Figure 1 Crystal structure packing diagram of the rare earth terbium metal organic complex stress luminescent material prepared in Example 1;

[0041] Figure 2 X-ray powder diffraction pattern (experimental) of the rare earth terbium metal organic complex stress luminescent material prepared in Example 1 and theoretical X-ray powder diffraction pattern (simulated) of the rare earth terbium metal organic complex stress luminescent material;

[0042] Figure 3 Photoluminescence excitation-emission spectrum diagram of the rare earth terbium metal organic complex stress luminescent material prepared in Example 1;

[0043] Figure 4 Stress luminescence photograph of the rare earth terbium metal organic complex stress luminescent material prepared in Example 1 under mechanical force in the dark;

[0044] Figure 5 Stress luminescence photograph of the rare earth terbium metal organic complex stress luminescent material prepared in Example 1 under mechanical force in bright light;

[0045] Figure 6 Stress luminescence spectrum diagram of the rare earth terbium metal organic complex stress luminescent material prepared in Example 1 under different mechanical forces;

[0046] Figure 7 Linear fitting diagram of the luminescence intensity of the rare earth terbium metal organic complex stress luminescent material prepared in Example 1 under different mechanical forces. Detailed implementation manners

[0047] Now, the various exemplary implementation manners of the present invention will 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, characteristics, and implementation schemes of the present invention.

[0048] It should be understood that the terms used in the present invention are only for describing specific embodiments and are not intended to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value and the intermediate values within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0049] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0050] Without departing from the scope or spirit of the present invention, various modifications and variations can be made to the specific embodiments of the present invention specification, which are obvious to those skilled in the art. Other embodiments obtained from the specification of the present invention are obvious to those skilled in the art. The specification and examples of the present invention are merely exemplary.

[0051] Regarding the use of "comprising", "including", "having", "containing", etc. herein, they are all open-ended terms, meaning including but not limited to.

[0052] It should be noted that those aspects not described in detail in the present invention are all conventional operating means in the art and are not the focus of the present invention.

[0053] The room temperature in the specific embodiments of the present invention refers to 20 - 30 °C.

[0054] The Trapen TMS in the specific embodiments of the present invention has the structural formula as The preparation method is as follows:

[0055] Mix o-nitrobenzyl bromide (A) with excessive ammonia water and react for 48 h to obtain bis(2-nitrobenzyl)amine (B) in the form of a yellow powder, and the separation yield is 71%;

[0056] Mix bis(2-nitrobenzyl)amine (B), 1.2 equivalents of o-nitrobenzyl bromide, and 5.0 equivalents of potassium carbonate (as the base), and reflux for 24 h to obtain tris(2-nitrobenzyl)amine (C) as a light yellow solid, and the yield is 87%;

[0057] The reduction reaction of tris(2-nitrobenzyl)amine (C) with hydrazine and palladium-carbon was carried out at 50 °C for 0.5 h to obtain Trapen (1);

[0058] Trapen (1) was treated with 3 equivalents of n-butyllithium, then 3 equivalents of trimethylchlorosilane (TMSCl) was added, and then 3 equivalents of n-butyllithium was added again. After the reaction, Trapen TMS (2) was obtained with a yield of 71%.

[0059] The chemical reaction equation is as follows:

[0060]

[0061] Example 1

[0062] A stress-luminescent material of rare-earth terbium metal-organic complex:

[0063] (1) In a nitrogen glove box, dry tetrahydrofuran was frozen in a refrigerator (temperature: -30 °C) for 1 h. Subsequently, the cooled ligand Trapen TMS (218 mg, 0.38 mmol) was dissolved in 38 mL of cold tetrahydrofuran (temperature: -30 °C) to obtain a Trapen TMS solution;

[0064] TbCl3 (153 mg, 0.57 mmol) was added to 2 mL of cold tetrahydrofuran (temperature: -30 °C), and it was stirred well at room temperature for 10 min to dissolve the raw materials in tetrahydrofuran, obtaining a TbCl3 solution.

[0065] (2) The Trapen TMS solution was sucked with a syringe and slowly dropped into the continuously stirred TbCl3 solution. Then, it was stirred at room temperature for 12 h. After the reaction, the solvent was removed under reduced pressure, extracted with toluene at room temperature, filtered, and the filtrate was dried by suction. Then, a small amount of tetrahydrofuran was added to dissolve it, and then an appropriate amount of hexane was added to start crystal growth in a refrigerator (temperature: -30 °C). It was left standing for 14 days, and pale yellow crystals were found to precipitate in the solution and were suitable for single-crystal X-ray diffraction analysis. After the reaction, the stress-luminescent material of the rare-earth terbium metal-organic complex was obtained, with a purity of 99% and a yield of 70%.

[0066] The crystal structure packing diagram of the stress-luminescent material of the rare-earth terbium metal-organic complex prepared in this example is shown in Figure 1 , and the crystallographic data are shown in Table 1.

[0067] Table 1 Crystallographic data

[0068]

[0069] Comparative Example 1

[0070] Same as Example 1, except that the amount of TbCl3 used was 102 mg (0.38 mmol).

[0071] After the reaction, the rare earth terbium metal-organic complex stress luminescent material was not obtained.

[0072] Comparative Example 2

[0073] Same as Example 1, except that the amount of TbCl3 used was 123 mg (0.46 mmol).

[0074] After the reaction, the rare earth terbium metal-organic complex stress luminescent material was not obtained.

[0075] Comparative Example 3

[0076] Same as Example 1, except that the solvent tetrahydrofuran was replaced with hexane.

[0077] After the reaction, the rare earth terbium metal-organic complex stress luminescent material was not obtained.

[0078] Comparative Example 4

[0079] The ligand Trapen TMS (218 mg, 0.38 mmol) and TbCl3 (153 mg, 0.57 mmol) were added to 40 mL of tetrahydrofuran cooled to -30 °C and stirred at room temperature for 12 h. After the reaction was completed, the solvent was removed under reduced pressure, extracted with toluene at room temperature, filtered, and then the filtrate was dried. Then, a small amount of tetrahydrofuran was added to dissolve it, and then an appropriate amount of hexane was added and allowed to stand in the refrigerator (temperature -30 °C) for 14 days. The rare earth terbium metal-organic complex stress luminescent material was not obtained.

[0080] Effect Example 1

[0081] (1) The X-ray powder diffraction pattern (experimental) of the rare earth terbium metal-organic complex stress luminescent material prepared in Example 1 and the theoretical X-ray powder diffraction pattern (simulated) of the rare earth terbium metal-organic complex stress luminescent material are shown in Figure 2 .

[0082] It can be seen from Figure 2 that in Example 1, the rare earth terbium metal-organic complex stress luminescent material was successfully synthesized; all the diffraction peaks of the rare earth terbium metal-organic complex stress luminescent material prepared in Example 1 were consistent with the simulated crystal data, indicating that the material prepared in Example 1 had a high purity.

[0083] (2) The photoluminescence excitation-emission spectrum of the rare earth terbium metal-organic complex stress luminescent material prepared in Example 1 is shown inFigure 3 .

[0084] As can be seen from Figure 3 , the excitation spectrum of the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 covers the ultraviolet region and extends to the visible light region, and the characteristic transition peak of Tb 3+ ion 5 D4→ 7 F J is observed.

[0085] (3) The stress luminescence photograph of the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 after applying mechanical force under dark conditions (only manually applying mechanical force without photoexcitation) is shown in Figure 4 .

[0086] As can be seen from Figure 4 , the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 produces bright green light under the stimulation of mechanical force.

[0087] (4) The stress luminescence photograph of the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 after applying mechanical force under bright conditions (only manually applying mechanical force without photoexcitation) is shown in Figure 5 .

[0088] As can be seen from Figure 5 , the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 produces green light visible to the naked eye under bright natural light under the stimulation of mechanical force.

[0089] (5) Transfer 3 g of the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 to a 3×3 cm square mold, then wrap the rare earth terbium metal-organic complex stress luminescence material with a PET film, and perform thermoforming on the wrapped film with a laminator to obtain a transparent composite film as a stress luminescence film.

[0090] The stress luminescence spectrogram of the stress luminescence film prepared with the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 under different mechanical forces (5 N, 10 N, 15 N, 20 N, 25 N, 30 N, 35 N, 40 N) is shown in Figure 6 , and the linear fitting diagram of the luminescence intensity is shown in Figure 7 .

[0091] The stress luminescence peak of the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 is located near 547 nm, showing the stress luminescence spectrum of the complex under different mechanical forces (5 N, 10 N, 15 N, 20 N, 25 N, 30 N, 35 N, 40 N) ( Figure 6 ) and the corresponding intensity integral diagram (Figure 7 )。 In Figure 6 , the horizontal axis is the wavelength and the vertical axis is the luminescence intensity. Different curves represent the spectral responses under different forces. As the applied force increases, the intensity of the main luminescence peak increases significantly. Figure 7 The intensity integral graph of further quantifies this trend: the total luminescence intensity increases approximately linearly with the increase of the force.

[0092] And it can be seen from Figure 7 that within a certain range, there is a good linear relationship between the stress luminescence intensity of the rare earth terbium metal-organic complex stress luminescence material prepared in Example 1 and the magnitude of the applied mechanical force.

[0093] The above-described embodiments are only descriptions of the preferred modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A stress luminescence material of rare earth terbium metal organic complex, characterized in that, The structural general formula is [(X)Tb(THF)]; where X is The unit cell parameters are α = 90°, β = 101°, γ = 90°.

2. A preparation method of the stress luminescence material of the rare earth terbium metal organic complex described in claim 1, characterized in that, It includes the following steps: Mix Trapen TMS , THF and terbium salt, and prepare the rare earth terbium metal-organic complex stress luminescence material by the solvent evaporation method; The Trapen TMS has the structural formula of: wherein, TMS is trimethylsilyl.

3. The preparation method according to claim 2, wherein The terbium salt includes terbium chloride.

4. The preparation method according to claim 2, characterized in that, The preparation method of the rare earth terbium metal organic complex stress luminescent material includes the following steps: Mix Trapen TMS , THF and terbium salt, remove THF after stirring and reacting, extract with toluene, filter, dry the filtrate by suction, then dissolve it in THF, add hexane, and let it stand at low temperature to obtain the stress luminescent material of the rare earth terbium metal organic complex.

5. The preparation method according to claim 4, characterized in that, The time of the stirring reaction is 12 to 15 h.

6. The preparation method according to claim 4, characterized in that, The temperature of the low-temperature standing is -30 °C, and the time is ≥ 14 days.

7. The preparation method according to claim 4, characterized in that, The Trapen TMS and terbium salt have a molar ratio of 1:1.

5.

8. Application of the rare earth terbium metal organic complex stress luminescent material according to claim 1 in the field of intelligent sensing.

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