A smart responsive organic luminescent material and its preparation method and application

Abstract

The present invention discloses an intelligent responsive organic light-emitting material and its preparation method and application, belonging to the technical field of organic light-emitting materials. When the donor material is phenoxathiophene, the complex emits yellow light. When the donor material is dibenzodioxin, the complex emits blue light. Through in-depth research on the complex, it was found that the complex has aggregation-induced luminescence properties, and the complex material is very sensitive to temperature changes. The response time accelerates with increasing temperature. The higher the temperature, the faster the response speed, and the lower the temperature, the slower the response speed. When the temperature rises to a certain critical point, the luminescence of the complex will be quenched. When the heat source is removed, as the temperature decreases, the complex gradually returns to its original luminescence color, that is, it exhibits a reversible temperature fluorescence response.

Description

Technical Field

[0001] The present invention relates to the technical field of organic luminescent materials, and in particular to an intelligent responsive organic luminescent material and a preparation method and application thereof. Background Art

[0002] With the rapid development of science and technology, people's requirements for material performance are increasing day by day, especially in the fields of information technology, biomedicine, environmental monitoring, etc. Traditional materials can no longer meet the complex and changing application requirements. Smart responsive materials, as a new type of material that can quickly respond to external stimuli (such as temperature, light, electric field, pH value, etc.) and change its own properties, have received widespread attention and research in recent years. Among them, smart responsive organic light-emitting materials, as an important branch, not only have excellent luminescent properties, but also can achieve real-time monitoring and regulation of the external environment through intelligent response mechanisms. Therefore, they show great application potential in display technology, sensors, bioimaging, ultrafast lasers and other fields.

[0003] In recent years, researchers have continuously pursued technological innovations, achieving significant progress in designing a series of novel donor-acceptor materials with specialized molecular structures and stable organic light-emitting materials. Organic donor-acceptor complexes are organic materials composed of electron donors and electron acceptors self-assembled through non-covalent intermolecular interactions. These complexes not only maintain the properties of their original components but can also exhibit novel properties through eutectic engineering. Furthermore, their weak intermolecular interactions make them sensitive to external environments. The internal structure or forces of crystalline materials are easily altered by external stimuli, resulting in unique physical properties.

[0004] Although important progress has been made in the research of smart responsive organic light-emitting materials, the research on two-component smart light-emitting materials is still in its initial stage. The existing preparation methods of smart responsive organic light-emitting materials lead to high production costs, poor stability of the prepared materials, and the luminescence intensity and luminescence life need to be further improved. Summary of the Invention

[0005] The present invention provides an intelligent responsive organic light-emitting material, a preparation method and an application thereof, which effectively solve the technical problems of high production cost, poor stability of the prepared organic light-emitting material, insufficient luminous intensity and short luminous lifetime caused by the existing preparation method of the intelligent responsive organic light-emitting material. The present invention uses thiophene oxathiolate (OSA) or dibenzodioxin (OOA) as a donor and 3,4,5,6-tetrafluorophthalonitrile (TFBN) as an acceptor to successfully synthesize OSA-TFBN or OOA-TFBN intelligent organic donor-acceptor complex materials, i.e., intelligent responsive organic light-emitting materials. The materials have excellent optical properties and aggregation-induced emission properties, are very sensitive to temperature changes, and the response speed increases with increasing temperature. The materials also have good reversibility and can be written and erased multiple times.

[0006] The first object of the present invention is to provide a method for preparing an intelligent responsive organic light-emitting material, comprising the following steps:

[0007] 3,4,5,6-tetrafluorophthalonitrile (structural formula: The molecular weight is 200.093, the melting point is 81~86℃) as the receptor, with phenoxathiol (structural formula: Molecular weight is 200.256, melting point is 52-56℃) or dibenzo-p-dioxin (structural formula: The molecular weight is 184.191, and the melting point is 200° C.) is used as a donor, and the acceptor and the donor are self-assembled by a grinding method to obtain an intelligent responsive organic light-emitting material.

[0008] As a preferred embodiment, the molar ratio of the 3,4,5,6-tetrafluorophthalonitrile to the dibenzoheterocyclohexadiene compound is 1:1.

[0009] As a preferred embodiment, 3,4,5,6-tetrafluorophthalonitrile and phenoxathiophene or dibenzodioxin are mixed and ground to obtain a smart responsive organic light-emitting material.

[0010] As a preferred embodiment, the grinding time is 1 to 4 minutes.

[0011] The second object of the present invention is to provide an intelligent responsive organic light-emitting material prepared by the above preparation method.

[0012] As a preferred embodiment, the aggregation-induced luminescence of the smart responsive organic light-emitting material is yellow light or blue-green light.

[0013] The third object of the present invention is to provide an application of the above-mentioned intelligent responsive organic light-emitting material in the preparation of temperature-responsive anti-counterfeiting materials.

[0014] As a preferred embodiment, the application specifically comprises: preparing a dichloromethane solution of the smart responsive organic light-emitting material, soaking the anti-counterfeiting material with the solution, and drying at room temperature.

[0015] As a preferred embodiment, the concentration of the dichloromethane solution of the smart response type organic light-emitting material is 0.05 mol / L to 0.07 mol / L.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention provides an intelligent responsive organic light-emitting material, a preparation method thereof, and an application thereof. 3,4,5,6-tetrafluorophthalonitrile is used as an acceptor, and phenoxathiophene or dibenzodioxin is used as a donor. The acceptor and the donor are self-assembled by a grinding method to obtain an intelligent responsive organic light-emitting material. When the donor material is phenoxathiophene, the composite emits yellow light. When the donor material is dibenzodioxin, the composite emits blue light. Through in-depth research on the composite, it was found that the composite has aggregation-induced luminescence properties, and the composite material is very sensitive to temperature changes. The response time accelerates with increasing temperature. The higher the temperature, the faster the response speed, and the lower the temperature, the slower the response speed. When the temperature rises to a certain critical point, the luminescence of the composite will be quenched. When the heat source is removed, as the temperature decreases, the composite gradually returns to its original luminescence color, that is, it exhibits a reversible temperature fluorescence response. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 These are the fluorescence images of phenoxathiol (OSA), dibenzodioxin (OOA), thiophenethane (SSA), and 3,4,5,6-tetrafluorophthalonitrile (TFBN) under ultraviolet light at room temperature in the present invention, where Figure A is OSA, Figure B is OOA, Figure C is SSA, and Figure D is TFBN.

[0019] Figure 2 This is a fluorescence image change diagram of OSA and TFBN ground for 1 to 4 minutes at room temperature according to the present invention.

[0020] Figure 3 This is a fluorescence image change diagram of OOA and TFBN grinding for 1 to 4 minutes at room temperature according to the present invention.

[0021] Figure 4 This is a fluorescence image change diagram of SSA and TFBN ground for 1 to 4 minutes at room temperature according to the present invention.

[0022] Figure 5 Figure a in the middle is the fluorescence spectra of OSA, TFBN, and OSA-TFBN; Figure b is the fluorescence spectra of OOA, TFBN, and OOA-TFBN; Figure c is a comparison of the XRD diffraction images of SSA, TFBN, and SSA-TFBN.

[0023] Figure 6 Figure a in the middle is a comparison of the XRD diffraction images of OSA, TFBN, and OSA-TFBN; Figure b is a comparison of the XRD diffraction images of OOA, TFBN, and OOA-TFBN.

[0024] Figure 7 Figure a in the middle shows the emission spectra of OSA-TFBN in mixed solvents of DMSO and H2O at different ratios; Figure b shows the emission spectra of OSA, TFBN, and OSA-TFBN in DMSO solution.

[0025] Figure 8 Figure a in the middle shows the emission spectra of OOA-TFBN in mixed solvents of DMSO and H2O in different proportions; Figure b shows the emission spectra of OOA, TFBN, and OOA-TFBN in DMSO solution.

[0026] Figure 9 This is a graph of the reaction of OSA and TFBN at room temperature for 72 hours according to the present invention.

[0027] Figure 10 This is a graph showing the response speed of OSA and TFBN at different temperatures in the present invention.

[0028] Figure 11 This is a fluorescence quenching image change diagram of OSA-TFBN at 45°C of the present invention.

[0029] Figure 12 This is a fluorescence recovery image change diagram of OSA-TFBN at room temperature in the present invention.

[0030] Figure 13 This is a graph of the reaction of OOA and TFBN at room temperature for 72 hours according to the present invention.

[0031] Figure 14 This is a graph showing the response speed of OOA and TFBN at different temperatures in the present invention.

[0032] Figure 15 This is a fluorescence quenching image change diagram of OOA-TFBN at 75°C of the present invention.

[0033] Figure 16 This is a fluorescence recovery image change diagram of OOA-TFBN at room temperature in the present invention.

[0034] Figure 17 Graphs showing the response rates of SSA and TFBN at different temperatures of the present invention; Graph A is at 70°C, Graph B is at 80°C, Graph C is at 90°C, and Graph D is at 100°C.

[0035] Figure 18 Schematic diagram of the reversible luminescence process of OSA-TFBN under ultraviolet light irradiation of the present invention.

[0036] Figure 19 Schematic diagram (three-dimensional diagram) of four rounds of reversible fluorescence changes of OSA-TFBN of the present invention.

[0037] Figure 20 Schematic diagram of four rounds of reversible fluorescence changes of OSA-TFBN of the present invention (two-dimensional diagram). DETAILED DESCRIPTION

[0038] To enable those skilled in the art to better understand and implement the technical solutions of the present invention, the present invention is further described below with reference to specific examples and accompanying drawings. However, the examples are not intended to limit the present invention. The following experimental and detection methods are conventional methods unless otherwise specified; the reagents and raw materials are commercially available unless otherwise specified.

[0039] Regarding the background of this invention, which mentions that research on two-component smart luminescent materials is still in its early stages, existing methods for preparing smart responsive organic luminescent materials result in high production costs, poor material stability, and the need to further improve luminescence intensity and lifetime, the present invention provides a smart responsive organic luminescent material, a preparation method, and applications thereof.

[0040] The technical solutions and effects of the present invention are described below with reference to the embodiments.

[0041] Experimental steps:

[0042] Preparation: Remove the necessary medications from the medicine cabinet. Prepare two clean medicine spoons, a clean natural agate mortar, and some paper towels. Calculate the required grams of the guest material based on the relative molecular mass of the host material and a molar ratio of 1:1.

[0043] Turn on the electronic balance and press the Tare / Zero key. The weighing table of the required materials is shown in Table 1. After the balance reading stabilizes, record the number of grams weighed.

[0044] Transfer the medicine on the weighing paper to the sides of the mortar, illuminate it with ultraviolet light, observe the luminescent color of the single-component medicine and take photos to record it. Figure 1 As shown, before grinding, TFBN is a white crystal that emits blue light under ultraviolet light, OSA is a white crystal that hardly emits light under ultraviolet light, and OOA is a white powder that hardly emits light under ultraviolet light.

[0045] Table 1 Weighing table of required materials

[0046] Luminescent materials Relative molecular mass Amount to be taken / g Actual amount / g TFBN 200.093 0.0400g 0.0408g OSA 200.256 0.0400g 0.0402g OOA 184.191 0.0368g 0.0372g

[0047] Example 1

[0048] A method for preparing an intelligent responsive organic light-emitting material comprises the following steps:

[0049] 0.0402g OSA and 0.0408g TFBN were poured into a mortar and ground clockwise for 4 minutes to obtain an organic charge transfer complex, which was recorded as OSA-TFBN complex. During grinding, ultraviolet light was used for observation. The color changes under fluorescent light and ultraviolet light were observed every 1 minute of grinding and photographed. The fluorescence image is shown as follows: Figure 2 As shown in the figure, it was found that OSA and TFBN reacted with slight force during the grinding process. As the grinding time increased, the color of the powder turned slightly yellow under fluorescent light, and under ultraviolet light, the composite material showed a bright yellow fluorescence that was significantly different from the single-component material.

[0050] Example 2

[0051] A method for preparing an intelligent responsive organic light-emitting material comprises the following steps:

[0052] 0.0372g OOA and 0.0408g TFBN were poured into a mortar and ground clockwise for 4 minutes to obtain an organic charge transfer complex, which was recorded as OSA-TFBN complex. During grinding, ultraviolet light was used for observation. The color changes under fluorescent light and ultraviolet light were observed every 1 minute and photographed. The fluorescence image is shown in the figure. Figure 3 As shown, with the increase of grinding time, the powder color turns white under fluorescent light, and under ultraviolet light, the composite material exhibits blue fluorescence that is significantly different from the single-component material.

[0053] In order to further demonstrate the technical effect of the present invention, the present invention also provides a comparative example, which is as follows:

[0054] Comparative Example 1

[0055] A method for preparing an SSA-TFBN dopant comprises the following steps:

[0056] 0.0432 g of thianthrene (SSA structural formula: The molecular weight of the product was 216.32) and 0.0400 g of TFBN were poured into a mortar and ground clockwise for 4 min to obtain a dopant of SSA and TFBN, which was recorded as SSA-TFBN dopant. During the grinding process, ultraviolet light was used for observation. The color change under fluorescent light and ultraviolet light was observed every 1 min of grinding and photographed. The fluorescence image was shown in the figure below. Figure 4 As shown, no matter how long the powder is ground, the color of the powder is white under fluorescent light, and the SSA-TFBN dopant material does not show a fluorescent color different from that of the single-component material under ultraviolet light.

[0057] The structure and performance of the smart responsive organic light-emitting material prepared above were characterized. The specific process and results are as follows:

[0058] 1. Structural Characterization

[0059] 1.1 Fluorescence spectrum

[0060] ① Preparation: UV lamp, tweezers, weighing paper, toilet paper, anhydrous ethanol, dichloromethane, filter, choose a solid sample tank or liquid sample tank according to the state of the substance to be tested.

[0061] ② Turn on the computer, instrument, and software in sequence, turn on the xenon lamp, and preheat for half an hour to reduce experimental errors.

[0062] ③ Select an appropriate excitation light source and set the emission light source to the wavelength range of the sample to be measured. Re-measure the emission light source based on the excitation light source to obtain the optimal emission spectrum under appropriate conditions.

[0063] ④After the test, turn off the instrument and computer and clean the desktop.

[0064] ⑤ Draw a fluorescence spectrum and analyze the maximum emission peak, intensity, etc. of the material based on the drawn fluorescence spectrum.

[0065] The organic donor-acceptor complex is obtained by self-assembly of a donor and an acceptor. The donor OSA emits almost no light under ultraviolet light, while the acceptor TFBN emits blue light under ultraviolet light. After grinding the two materials together, the OSA-TFBN complex material emits yellow light. The donor OOA emits almost no light under ultraviolet light, while the acceptor TFBN emits blue light under ultraviolet light. After grinding, the OOA-TFBN complex emits a bright blue light that is different from the single-component material. The luminescent color of the products has changed significantly, indicating that a new substance has been generated. To prove the generation of a new organic donor-acceptor complex material, the spectral images of the complex and the donor and acceptor materials were tested and compared using a fluorescence spectrometer to further prove that a new substance has been generated, rather than simple physical doping.

[0066] Depend on Figure 5 As shown in Figure a, the donor material OSA has a maximum emission peak of 445 nm and emits almost no light under UV light. The acceptor material TFBN has a maximum emission peak of 325 nm and emits blue light under UV light. However, the OSA-TFBN composite material has a maximum emission peak of 535 nm and emits yellow light. Compared to the fluorescence spectra of the two individual components, the fluorescence wavelength of the composite is red-shifted, indicating that the fluorescence of the composite is derived from the interaction of two molecules, rather than the emission of a single substance.

[0067] Figure 5As shown in Figure b, the maximum emission peak of the donor material OOA is 375nm, exhibiting almost no luminescence under UV light. The maximum emission peak of the acceptor material TFBN is 325nm, exhibiting blue luminescence under UV light. However, the maximum emission peak of the OOA-TFBN composite material is 485nm, exhibiting a distinctly different blue emission from the individual materials. Compared to the fluorescence spectra of the two individual materials, the wavelength of the composite's fluorescence is significantly red-shifted, indicating that the composite's fluorescence originates from the combined action of two molecules, rather than from the emission of a single substance.

[0068] Depend on Figure 5 As can be seen from Figure C, since the single-component material SSA hardly emits light, the SSA-TFBN two-component material exhibits a single emission spectrum of TFBN during spectral testing.

[0069] 1.2XRD spectrum

[0070] ① Preparation: UV lamp, alcohol cotton balls, tweezers, weighing paper, toilet paper, sample preparation trough.

[0071] ② Follow the operating procedures to turn on the circulating condenser water, power switch, and panel switch. Adjust the scanning angle between 5° and 60° as needed. Complete the XRD test according to the operating procedures and obtain the XRD spectrum. Use Origin to plot and analyze the spectrum.

[0072] In order to further prove the formation of organic donor-acceptor complex, we used X-ray powder diffractometer to further characterize the complex and single-component donor and acceptor materials. Figure 6 As shown in Figure a, the diffraction pattern of OSA-TFBN is significantly different from that of single-component OSA and TFBN. A new diffraction peak appears at 10° to 30°, indicating that during the grinding process, OSA-TFBN is not simply physically doped, but forms a relatively stable structure under the stimulation of external forces, thus producing a diffraction peak different from that of a single component. Figure 6 As shown in Figure b, the diffraction pattern of the grinding product OOA-TFBN is significantly different from the diffraction patterns of single-component OOA and TFBN. New diffraction peaks appear at 10°~30°, indicating that during the grinding process, OOA-TFBN is not simply physically doped, but forms a relatively stable structure under the stimulation of external force, thereby producing diffraction peaks different from those of single components.

[0073] 2. Aggregation-induced emission properties

[0074] 2.1 Aggregation-induced emission (AIE) sample preparation

[0075] Aggregation-induced emission (AIE) is a fluorescence phenomenon that differs from traditional solution-state fluorescence. While traditional fluorescent materials are quenched in solution due to intermolecular aggregation, AIE materials do not emit light in solution. However, when they form aggregates or solid structures, they exhibit distinct luminescence properties.

[0076] The experimental steps are as follows:

[0077] ① Using the molar concentration formula (C = n / V), calculate a 10 mL stock solution of the complex material with a concentration of 7 × 10-2 mol / L. Prepare a 10 mL glass vial, a 1000 μL pipette with an appropriate tip, dimethyl sulfoxide (DMSO), deionized water, and twenty 3 mL vials.

[0078] ② Calculations show that the required two-component materials for AIE of the OSA-TFBN composite material are 0.2800 g, and 0.02702 g for the OOA-TFBN composite material. Weigh the required two-component materials using an electronic balance and place them into 10 mL glass bottles. Add 10 mL of DMSO solution to each bottle, shake well, label the solution, and set aside.

[0079] ③ Use a marker to mark the caps of ten 3 mL glass vials with 0, 10, 20, 30, 40, 50, 60, 70, 80, and 90, representing the water content of the solution. Add 300 μL of the stock solution to each vial. Add the corresponding amount of deionized water according to the markings on the cap. Make up any volume less than 3 mL with DMSO solution. The actual amounts of each solution are shown in Table 2.

[0080] Table 2 Liquid volume required for aqueous solutions of different concentrations

[0081]

[0082]

[0083] ④ Place the prepared solutions with different water contents in an ultrasonic instrument for ultrasonic treatment to disperse the materials evenly in the solution and avoid uneven molecular aggregation that may affect the experimental results.

[0084] ⑤ Use a fluorescence spectrometer to perform fluorescence spectrum analysis on DMSO solutions of complexes with different water contents. Use Origin to plot the measured fluorescence spectra on the same graph, and normalize some of the spectra to more intuitively observe the changes in fluorescence peak position and fluorescence intensity with different water contents.

[0085] ⑥ Secure the phone and UV lamp to ensure the phone's focus, exposure, and other performance are as consistent as possible. Use a pipette to transfer 1800 μL of the 90% water solution into a 10 mm quartz cuvette and take a photo. After taking the photo, return the solution to the corresponding small glass vial.

[0086] ⑦ Rinse the quartz cuvette with anhydrous ethanol first, then with dichloromethane. After washing, wipe off the unvolatile dichloromethane with a paper towel, and then wipe off the small paper scraps on the quartz cuvette with high-grade lens paper.

[0087] ⑧Repeat steps ⑥⑦ to complete the photography of ten solutions with different water contents.

[0088] ⑨Use PS to combine ten photos into a group photo.

[0089] 2.2 Aggregation-induced emission performance results

[0090] Depend on Figure 7 As can be seen in Figure a, the maximum emission peak of OSA-TFBN in DMSO is at 440nm, showing blue light emission. As the water concentration increases, the blue light intensity gradually increases and then decreases. In order to prove the source of the blue light emission, we tested the fluorescence spectrum of the single-component material in DMSO. Figure 7 As shown in Figure b, the blue light emission of the complex is essentially consistent with that of TFBN, indicating that the blue light likely originates from TFBN. When the water concentration reaches 70%, yellow light begins to appear, and the yellow light emission reaches its peak at 90%, demonstrating distinct aggregation-induced emission characteristics.

[0091] Depend on Figure 8 As can be seen in Figure a, the maximum emission peak of OOA-TEBN in DMSO is at 440nm, showing blue light emission. As the water concentration increases, the blue light intensity gradually increases and then decreases. In order to prove the source of blue light emission, we tested the fluorescence spectrum of the single-component material in DMSO, as shown in the figure. Figure 8 As shown in Figure b, the blue light emission of the complex is essentially consistent with that of TFBN, indicating that the blue light likely originates from TFBN. When the water concentration reaches 80%, blue-green light appears, and at 90% water concentration, the blue-green emission reaches its peak, demonstrating aggregation-induced emission characteristics.

[0092] 3. Reversible optical properties under external temperature stimulation

[0093] 3.1 Sample preparation

[0094] ① Turn on the heating stage and set the temperature required for the test.

[0095] ② Prepare a clean glass slide, two holders, a UV lamp, and a clean medicine spoon. Calculate the required grams of host and guest materials based on a 1:1 molar ratio.

[0096] ③ Turn on the electronic balance, fold the weighing paper diagonally and place it on the balance, press the Tare / Zero button on the balance, and when the balance reads zero, use a medicine spoon to transfer an appropriate amount of medicine to the weighing paper. According to the known data, weigh 0.0100g of TFBN and 0.0100g of OSA for each experimental temperature, and weigh 0.0100g of TFBN and 0.0092g of OOA for the other material. After the balance reading stabilizes, record the number of grams weighed.

[0097] ④ Use a medicine spoon to transfer the weighed medicine to the glass slide so that the two single-component medicines are in contact with each other.

[0098] ⑤ Place a bracket on the left side of the heating table that has reached the set temperature to secure your phone for recording video. Use another bracket on the right side of the heating table to secure the UV lamp. Turn on the UV lamp and shine it onto the heating table. Turn on the phone's video mode, adjust the magnification and focus, and carefully transfer the glass slide to the heating table. Observe the reaction time of the two-component material.

[0099] ⑥ After heating, turn off the heating table, transfer the heated material from the glass slide to the mortar, grind it thoroughly and collect it into the corresponding centrifuge tube.

[0100] ⑦ Clean used glass slides, medicine spoons, mortars and other instruments with anhydrous ethanol and dichloromethane, put them back in their original places, and put the medicines back into the medicine cabinet.

[0101] ⑧Turn off the electronic balance.

[0102] ⑨Process the recorded video, use PS to draw a group of screenshots processed according to a certain time, and mark the corresponding time.

[0103] 3.2 Reversible optical properties under external temperature stimulation

[0104] First, the assembly ability of the donor and the acceptor at room temperature was studied. It was found that the assembly ability of the donor and the acceptor at room temperature was relatively weak, and the interface between OSA and TFBN hardly changed within 72 hours. Figure 9 Then the assembly ability of OSA and TFBN at different temperatures (30℃, 35℃, 40℃, 45℃) was studied, and it was found that the OSA-TFBN complex was very sensitive to temperature and had a fast response speed. Figure 10It can be seen that when the temperature rises from 30℃ to 45℃, the response speed of OSA and TFBN is shortened from 45min to 75s, which proves that the response speed of OSA and TFBN assembly gradually increases with the increase of temperature. In addition, during the experiment, we found that at 45℃, the yellow fluorescence generated by the reaction will gradually quench as the heating time increases. Therefore, we studied the luminescence changes of the composite material at 45℃, such as Figure 11 As shown. The results show that when OSA-TFBN is at 45℃, the yellow fluorescence gradually quenches over time. The experimental results show that 45℃ can quench the luminescence of the complex. The quenched complex is removed from the heating table and placed at room temperature. When the temperature of the complex gradually cools down, it is found that the originally quenched complex gradually returns to its original yellow fluorescence over time, as shown in Figure 2. Figure 12 As shown above. In summary, the OSA-TFBN complex is a temperature-sensitive material with reversible stimuli-responsive optical properties. The complex's response speed is affected by temperature: higher temperatures increase the response speed, while lower temperatures decrease the response speed. When a certain temperature is reached, the complex's luminescence color is quenched. Cooling the quenched complex to room temperature gradually restores its original optical properties.

[0105] For OOA and TFBN, as with the former, we first studied the assembly ability of the donor and the acceptor at room temperature. We found that the assembly ability of the donor and the acceptor at room temperature was relatively weak, and the interface between OOA and TFBN hardly changed after 72 hours. Figure 13 Then the assembly ability of OOA and TFBN at different temperatures (70℃, 80℃, 90℃) was studied, and it was found that OOA-TFBN was also sensitive to temperature and had a faster response speed. Figure 14 It can be seen that when the temperature rises from 70℃ to 90℃, the response speed of OOA and TFBN shortens from 120s to 10s, proving that the response speed of OOA and TFBN assembly gradually increases with the increase of temperature. In addition, during the experiment, we found that at 75℃, the blue-green light will gradually quench. Therefore, we studied the luminescence changes of the composite material at 75℃, such as Figure 15 As shown. The results show that when OOA-TFBN is at 75℃, the blue-green light gradually quenches over time. The experimental results show that 75℃ can quench the luminescence of the complex. When the quenched complex is placed at room temperature, as the temperature of the complex gradually cools, the originally quenched complex gradually returns to its original fluorescence color, as shown in Figure 2. Figure 16As shown above. In summary, the OOA-TFBN complex is a temperature-sensitive, reversible stimuli-responsive material. The complex's response speed is affected by temperature: higher temperatures increase the response speed, while lower temperatures decrease the response speed. When a certain temperature is reached, the complex's luminescence color is quenched. Cooling the quenched complex to room temperature gradually restores its original optical properties.

[0106] Depend on Figure 17 It can be seen that the contact surface between SSA and TFBN has not changed at all from the change in heating temperature gradient. Combining the spectrum and heating temperature gradient change diagram, SSA and TFBN do not form a eutectic, but only a simple physical doping process.

[0107] 4. Application of smart responsive organic light-emitting materials in anti-counterfeiting

[0108] 4.1 Sample preparation

[0109] ① Prepare 3mL of 7×10 -2 Prepare a 10 mol / L solution of the OSA-TFBN complex in dichloromethane and set aside. Prepare several sheets of 2 × 2 cm patterned filter paper. Cut or create patterns as needed for the experiment. Moisten the filter paper with the dichloromethane solution of the complex and allow it to dry at room temperature.

[0110] ② Under the irradiation of ultraviolet light, give the filter paper a certain temperature, observe the changes in the luminous color of the filter paper where the ultraviolet light is irradiated, and take photos to record.

[0111] ③Wait for a while, observe the changes in the luminous color of the area irradiated by the ultraviolet light, and repeat steps ② and ③.

[0112] 4.2 Anti-counterfeiting application results

[0113] Based on the reversible optical properties of the composite material under external temperature stimulation, the present invention uses a dichloromethane solution of the OSA-TFBN composite to design a reversible temperature-sensitive anti-counterfeiting application. When filter paper is soaked in the dichloromethane solution of OSA-TFBN, under ultraviolet light, the originally non-luminescent filter paper gradually emits a yellow fluorescence as the solvent evaporates. Figure 18 Schematic diagram of the reversible luminescence of OSA-TFBN under UV light. When UV light is shone closely on the pattern below, the luminescence color of the illuminated areas is quenched. Over time, the quenched areas gradually return to yellow luminescence. Figure 19 This is a schematic diagram of the four rounds of reversible fluorescence changes of OSA-TFBN. Color quenching occurs where ultraviolet light is irradiated, that is, the composite material is sensitive to temperature, and the color quenches where the temperature rises. When the heat source is removed, the luminescent color recovers after a certain period of time. Figure 20The composite material demonstrates good repeatability, maintaining good optical properties after four rounds of writing and erasing.

[0114] 5. Conclusion

[0115] This invention develops a series of smart-responsive organic donor-acceptor composite materials using 3,4,5,6-tetrafluorophthalonitrile (TFBN) as an acceptor material and phenoxathiol (OSA) and dibenzodioxin (OOA) as donor materials. These composite materials not only exhibit unique optical properties but also show significant optical responses to external stimuli, providing broad potential for future applications.

[0116] The present invention observed that when the donor material is phenoxathiol (OSA), the prepared composite emits yellow light when stimulated by external stimuli. However, when the donor material is replaced with dibenzodioxin (OOA), the composite emits blue light, providing diverse applications for composite materials in the optical field.

[0117] To demonstrate the successful design and synthesis of the composite material, the present invention used a fluorescence spectrometer to conduct an in-depth analysis. By comparing the spectral characteristics of the single-component material and the composite material, we found that the spectrum of the composite material showed a more obvious red shift compared to the spectrum of the single-component material. This change proves that a new substance has been produced. In addition, the structure of the composite material was characterized using an X-ray diffractometer. The results showed that the composite material showed diffraction peaks different from those of the single-component material. These spectra further prove that the composite material is not a simple physical doping of two single-component materials under external stimulation, but rather forms a relatively stable structure.

[0118] In further research, the present invention found that both composite materials exhibit unique aggregation-induced emission properties. When the composite materials are aggregated together, their luminescence performance is enhanced. This property makes these materials have potential application value in fields such as bioimaging. What is more worth mentioning is that these materials are highly sensitive to temperature and exhibit reversible stimulus response characteristics. Experimental data clearly show that as the temperature increases, the response speed of the material increases significantly; and when the temperature decreases, the response speed slows down accordingly. When the temperature reaches a certain value, the luminescence color of the composite material will be quenched. However, when these quenched composites are placed at room temperature and cooled, they can gradually restore their original optical properties. This shows that the composite material has reversible optical properties under external temperature stimulation. This reversible optical property gives these materials huge application potential in information storage, anti-counterfeiting encryption, sensing and other fields.

[0119] In summary, the present invention's intelligent, responsive organic donor-acceptor composites, prepared using 3,4,5,6-tetrafluorophthalonitrile (TFBN) as an acceptor material and phenoxathiol (OSA) and dibenzodioxin (OOA) as donor materials, exhibit unique optical properties and aggregation-induced emission (AIE) as well as reversible stimulus-responsiveness. These excellent properties hold great promise for applications in sensing, information storage, anti-counterfeiting, and encryption.

[0120] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for preparing an intelligent responsive organic light-emitting material, characterized in that: The following steps are involved: 3,4,5,6-tetrafluorophthalonitrile is used as an acceptor and phenoxathiol or dibenzodioxin is used as a donor. 3,4,5,6-tetrafluorophthalonitrile and phenoxathiol or dibenzodioxin are mixed and ground, and the acceptor and donor are self-assembled to obtain an intelligent responsive organic light-emitting material. The molar ratio of the 3,4,5,6-tetrafluorophthalonitrile to the phenoxathiol or dibenzodioxin is 1:

1.

2. The preparation method according to claim 1, characterized in that The grinding time is 1 to 4 minutes.

3. An intelligent responsive organic light-emitting material prepared by the preparation method according to any one of claims 1 or 2.

4. The smart responsive organic light-emitting material according to claim 3, characterized in that: The aggregation-induced luminescence of the smart responsive organic light-emitting material is yellow light or blue-green light.

5. Use of the smart responsive organic light-emitting material according to claim 4 in preparing a temperature-responsive anti-counterfeiting material.

6. The use according to claim 5, characterized in that The application specifically comprises: preparing a dichloromethane solution of the smart responsive organic light-emitting material, soaking the anti-counterfeiting material with the solution, and drying at room temperature.

7. The use according to claim 6, characterized in that The concentration of the dichloromethane solution of the smart response type organic light-emitting material is 0.05 mol / L to 0.07 mol / L.

Images