Method for massively synthesizing water-phase multicolor organic afterglow nano material by one-pot method

Abstract

The invention discloses a method for massively synthesizing a water-phase multicolor organic afterglow nano-material by a one-pot method, which comprises the following steps: by taking pure organic molecules as a raw material, performing simple heating reflux in a water phase, thereby obtaining the water-phase multicolor organic afterglow nano-material. The water-phase multicolor organic afterglow nano material capable of emitting bright blue fluorescence and emitting blue, green, yellow and red is prepared by a one-pot method, the yield is as high as 57.6%, the cost is as low as 0.13-0.64 yuan / g, and the average particle size is 9-11 nm. Compared with a solid material, the water-phase multicolor organic afterglow nano-material prepared by the preparation method disclosed by the invention is wider in application range, can be applied to pattern anti-counterfeiting and LED lamp strips, and can show afterglow of different colors, and blue afterglow lasting for about 5 seconds, green afterglow lasting for about 7 seconds, yellow afterglow lasting for about 6 seconds and red afterglow lasting for about 0.5 seconds can be observed by naked eyes. According to the method, the problems that the afterglow color is only blue and green, and the chromaticity is single are solved, and a large number of multicolor afterglow materials can be synthesized through the method.

Description

(I) Technical field

[0001] The invention belongs to the technical field of organic molecular afterglow materials, and in particular relates to a method for synthesizing a large amount of aqueous phase multicolor organic afterglow nanometer materials in a one-pot process. (II) Background technology

[0002] In vivo bio-optical imaging technology in molecular imaging technology has the advantages of non-invasiveness and high spatiotemporal resolution, and has become a powerful tool for disease diagnosis, treatment and monitoring. In recent years, in vivo bio-optical imaging technology (including fluorescence imaging, photoacoustic imaging and afterglow luminescence imaging, etc.) has attracted widespread attention. The principle of afterglow imaging is to use the phenomenon that the chemical defects of the material continue to emit light for a period of time after the external light irradiation stops, and perform bio-optical imaging. Afterglow materials are generally divided into inorganic afterglow materials and organic afterglow materials. Organic afterglow materials are generally composed of afterglow substrates, afterglow relay units and photosensitizers. Under external light irradiation, the photosensitizer is excited from the ground state (S0) to produce the lowest singlet excited state (S1) with a lifetime of several nanoseconds. Then, S1 is transformed into a high-energy triplet state (T1) through intersystem crossing (ISC), and the photon energy is transferred to the surrounding oxygen to produce singlet oxygen ( 1 O2). Subsequently, the afterglow base 1 O2 reacts to form an unstable intermediate, which can decompose to release heat energy and directly emit photons by inducing electron exchange through chemical reactions. Finally, the energy released by the intermediate continues to excite the surrounding afterglow relay units. If the excitation wavelength of the photosensitizer overlaps with the emission wavelength of the afterglow relay unit, the photosensitizer can be further excited to red-shift the afterglow emission.

[0003] Organic afterglow materials have the advantages of relatively simple preparation conditions, easy modification, good designability, good biocompatibility and environmental friendliness. However, the afterglow of pure organic molecules is not easy to achieve, mainly because the spin coupling of molecules is weak and the ISC rate is low. At the same time, triplet excitons are easily affected by the environment, such as oxygen, moisture, heat, and molecular vibration and rotation, which may quench triplet excitons and cannot achieve afterglow emission. However, in order to achieve afterglow emission of pure organic materials, two perspectives can be considered. One is in the design and selection of molecules, by selecting or introducing heavy atoms or heteroatoms to promote the ISC process; the other is in the regulation of aggregation behavior, mainly by selecting and constructing rigid structures and multiple interactions to suppress the non-radiative transition and quenching process of triplet excitons.

[0004] At present, most of the reported pure organic afterglow materials are mainly in solid form. The solid state can provide a rigid environment, which greatly restricts molecular motion, inhibits the non-radiative transition of triplet excitons, and realizes afterglow emission. However, the solid has poor modifiability and the preparation process is complicated, which is not conducive to large-scale and large-scale preparation. Aqueous afterglow materials have more development prospects. Some of these amorphous polymer materials are processed into nanomaterials, which can be dispersed in water to increase dispersibility, but the preparation process is still relatively complicated. Therefore, it is challenging to prepare aqueous organic afterglow materials by simple methods.

[0005] The pure organic long afterglow nano-carbon dots synthesized in patent CN 103694994 A improve their dispersibility in aqueous solution by adding water-soluble polymer polyvinyl alcohol; patent CN105754595A prepares an afterglow material based on ion doping, which takes a long time to prepare, has high solvent toxicity, and is in the form of powder crystals; patent CN116606220A invents a single-component organic afterglow compound, which can observe afterglow luminescence of different wavelengths in the aqueous phase, but it also dissolves the solid powder in the dimethyl sulfoxide organic reagent, and then dissolves it in the buffer solution to form an aqueous phase material. (III) Summary of the invention

[0006] The purpose of the present invention is to provide a method for synthesizing a large amount of aqueous phase multicolor organic afterglow nanomaterials by a one-pot method. The present invention is based on the fact that afterglow generation originates from certain fixed chromophores and the structure of organic molecules is clear. The organic afterglow material is directly synthesized in a large amount in an aqueous phase by a one-pot method. Different luminescent centers are generated by adding different reagents to react and multicolor afterglow is formed. There is no need to prepare a solid and then disperse it in water again. The operation is simple and the reagent toxicity is low. The yield is increased while the effect is guaranteed. Not only can a large amount of organic afterglow nanomaterials be synthesized, but time can also be saved and resource consumption can be reduced, so that the method is more efficient and faster.

[0007] The technical solution adopted by the present invention is:

[0008] The present invention provides a method for synthesizing a large amount of aqueous phase multicolor organic afterglow nanomaterials in a one-pot method, the method comprising the following steps:

[0009] (1) Organic fluorescent molecule solution: Add reagent A to ethanol aqueous solution at room temperature, and mix by ultrasonication; then add reagent S, mix by ultrasonication, and heat under reflux at 60-120° C. for 1-8 h to obtain an organic fluorescent molecule solution;

[0010] The reagent A is selected from one or more of an acid compound, an anhydride compound or an amine compound; the acid compound includes: succinic acid, 1,4-naphthalene dicarboxylic acid, 2-carboxypyrene; the anhydride compound includes: butyric anhydride, isobutyric anhydride, maleic anhydride, succinic anhydride, glutaric anhydride, 2,3-pyridine dicarboxylic anhydride, 1,2-naphthalene dicarboxylic anhydride, phthalic anhydride, 1,8-naphthalene dicarboxylic anhydride or more; the amine compound includes: ethylenediamine One or more of 1-[3-(triethoxysilyl)propyl]urea, (3-aminopropyl)trimethoxysilane, N-(trimethylsilylmethyl)benzylamine, 3-(2-aminoethylamino)propyltriethoxysilane;

[0011] (2) Aqueous multicolor organic afterglow nanomaterials: deionized water, ammonia water, and tetraethyl silicate (TEOS) are added to the organic fluorescent molecule solution obtained in step (1), and the solution is heated to reflux at 60-120°C for 1-8 hours. After the reflux is completed, the solution is naturally cooled to room temperature to obtain a multicolor afterglow nanomaterial aqueous solution, i.e., an aqueous multicolor organic afterglow nanomaterial.

[0012] The aqueous multicolor organic afterglow nanomaterial of the present invention can be further prepared into a solid multicolor organic afterglow nanomaterial: the multicolor afterglow nanomaterial aqueous solution in step (2) is centrifuged, precipitated and dried, and ground to obtain a white powder to obtain a solid multicolor afterglow nanomaterial powder.

[0013] Furthermore, the reagent A in step (1) is composed of an anhydride compound and / or an amine compound, and contains at least one rigid ring structure; the anhydride compound is selected from one or more of 2,3-pyridinedicarboxylic anhydride, 2,3-naphthalene dicarboxylic anhydride, 1,8-naphthalene dicarboxylic anhydride, maleic anhydride or 1,4,5,8-naphthalenetetracarboxylic anhydride; the amine compound is selected from one or more of propylene diamine, propylene glycol, urea, o-phenylenediamine, and ethylenediamine.

[0014] Furthermore, in step (1), the reagent S is selected from one or two of (3-aminopropyl)trimethoxysilane 1-[3-(triethoxysilyl)propyl]urea, N-(trimethylsilylmethyl)benzylamine, and 3-(2-aminoethylamino)propyltriethoxysilane.

[0015] Furthermore, the reagent A in step (1) is composed of one of the following: (1) 2,3-pyridinedicarboxylic anhydride and propylenediamine; (2) 2,3-naphthalene dicarboxylic anhydride, propylenediamine and urea; (3) 1,8-naphthalene dicarboxylic anhydride and maleic anhydride; (4) 1,4,5,8-naphthalenetetracarboxylic anhydride, o-phenylenediamine and ethylenediamine.

[0016] Furthermore, the volume concentration of the ethanol aqueous solution in step (1) is 20-100%, preferably 50%.

[0017] Furthermore, in step (1), the organic fluorescent molecule solution is prepared according to one of the following ratios:

[0018] ① Reagent A is a mixture of 2,3-pyridinedicarboxylic anhydride and propylenediamine at a ratio of 1.5mmol:2μL; Reagent S is a mixture of (3-aminopropyl)trimethoxysilane and N-(trimethylsilylmethyl)benzylamine) at a volume ratio of 1.8:1; the volume amount of reagent S is 28μL / 1.5mmol based on the amount of 2,3-pyridinedicarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 2,3-pyridinedicarboxylic anhydride;

[0019] ② Reagent A is a mixture of 2,3-naphthalene dicarboxylic anhydride, propylene diamine, and urea at a ratio of 1.5mmoL: 2μL: 0.5mmoL; Reagent S is a mixture of (3-aminopropyl) trimethoxysilane and 1-[3-(triethoxysilyl)propyl] urea) at a volume ratio of 1.8:1; the volume amount of reagent S is 28μL / 1.5mmol based on the amount of 2,3-pyridine dicarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 2,3-pyridine dicarboxylic anhydride;

[0020] ③ Reagent A is a mixture of 1,8-naphthalene dicarboxylic anhydride and maleic anhydride at a ratio of 1.5mmoL:5μL; Reagent S is a mixture of (3-aminopropyl)trimethoxysilane and N-(trimethylsilylmethyl)benzylamine at a volume ratio of 1.8:1; the volume amount of reagent S is 28μL / 1.5mmol based on the amount of 1,8-naphthalene dicarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 1,8-naphthalene dicarboxylic anhydride;

[0021] ④ Reagent A is a mixture of 1,4,5,8-naphthalenetetracarboxylic anhydride, o-phenylenediamine, and ethylenediamine in a ratio of 1.5mmoL:0.1mmoL:5μL; Reagent S is a mixture of (3-aminopropyl)trimethoxysilane and 3-(2-aminoethylamino)propyltriethoxysilane in a volume ratio of 1:1; the volume amount of reagent S is 36μL / 1.5mmol based on the amount of 1,4,5,8-naphthalenetetracarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 1,4,5,8-naphthalenetetracarboxylic anhydride.

[0022] Furthermore, step (1) is refluxed at 100° C. for 6 h.

[0023] Furthermore, in step (2), the volume ratio of the organic fluorescent molecule solution to deionized water is 1:5-15, preferably 1:10; the volume ratio of the organic fluorescent molecule solution to ammonia water is 1:0.1-1, preferably 1:0.2; the volume ratio of the organic fluorescent molecule solution to tetraethyl silicate is 1:1-3, preferably 1:1.5.

[0024] Furthermore, step (2) is refluxed at 100° C. for 5 h.

[0025] Furthermore, in step (2), the centrifugal speed is 8000-10000 rpm, the centrifugal time is 5-10 min, and the drying condition is heating and drying at 60° C. for 4 h.

[0026] The invention also provides an aqueous multicolor organic afterglow material prepared by the method.

[0027] The present invention also provides applications of the aqueous multicolor organic afterglow material prepared by the method, wherein the application includes being able to be used for preparing anti-counterfeiting patterns and LED light strips.

[0028] Compared with the prior art, the beneficial effects of the present invention are mainly reflected in:

[0029] The present invention uses pure organic molecules as raw materials. Compared with the complex synthesis, extraction, precipitation polymerization, inert gas protection and other steps in other methods, the present invention prepares a water-phase multicolor organic afterglow nanomaterial that can show bright blue fluorescence emission and blue, green, yellow, and red emission by a one-pot method through simple heating and reflux in the aqueous phase, with a yield of up to 57.6%, a cost as low as 0.13-0.64 yuan / gram, and an average particle size of 9-11nm. Compared with solid materials, the water-phase multicolor organic afterglow nanomaterial prepared by the present invention has a wider range of applications, can be applied to pattern anti-counterfeiting, LED light strips, and can show afterglow of different colors. The naked eye can observe a blue afterglow lasting about 5s, a green afterglow of about 7s, a yellow afterglow of about 6s, and a red afterglow of about 0.5s. The present invention solves the problem that the afterglow color is only blue and green, and the chromaticity is single. The method can synthesize a large amount of multicolor afterglow materials. (IV) Description of the drawings

[0030] Figure 1 Schematic diagram of the process for preparing multi-color afterglow materials.

[0031] Figure 2 This is an electron microscope image of the blue afterglow material prepared in Example 1.

[0032] Figure 3 This is the fluorescence spectrum of the multicolor afterglow materials prepared in Examples 1, 2, 3, and 4.

[0033] Figure 4 This is the afterglow spectrum of the multicolor afterglow materials prepared in Examples 1, 2, 3, and 4.

[0034] Figure 5 This is the ultraviolet-visible absorption spectrum of the blue afterglow material prepared in Example 1.

[0035] Figure 6 This is the infrared spectrum of the blue afterglow material prepared in Example 1.

[0036] Figure 7 These are the fluorescence and afterglow images of the aqueous multicolor afterglow material in Example 5.

[0037] Figure 8 This is the anti-counterfeiting pattern drawn with the aqueous multi-color afterglow material in Example 5.

[0038] Fig. 9 Schematic diagram (a), actual image (b) and CIE coordinate diagram (c) of a multi-color LED light strip made of the afterglow material prepared in Examples 1, 2, 3 and 4. (V) Specific implementation methods

[0039] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0040] Example 1: Blue organic afterglow material

[0041] 1. Reference Figure 1 , prepared as follows:

[0042] (1) Organic fluorescent molecule solution: At room temperature (25-30°C), reagent A1 (1.5 mmol 2,3-pyridinedicarboxylic anhydride, 2 μL propylenediamine) was added to 10 mL of 50% ethanol aqueous solution, and then ultrasonically mixed until completely dissolved. Then reagent S1 (18 μL (3-aminopropyl) trimethoxysilane, 10 μL N-(trimethylsilylmethyl) benzylamine) was added; ultrasonic mixing was continued, and the mixture was heated under reflux at 100°C for 6 h to obtain 10 mL of organic fluorescent molecule solution, which was recorded as A1-S1. The infrared spectrum is shown in FIG. Figure 6 shown.

[0043] (2) Aqueous blue afterglow material: 100 mL of deionized water, 2 mL of ammonia water, and 15 mL of tetraethyl silicate (TEOS) were directly added to 10 mL of A1-S1 obtained in step (1), and refluxed at 100 °C for 5 h for siliconization treatment; after the reflux, the mixture was naturally cooled to room temperature to obtain 127 mL of a slightly white solution, i.e., a blue afterglow material solution, recorded as A1-S1@SiO2.

[0044] (3) Solid-phase blue afterglow material: The blue afterglow material solution of step (2) was centrifuged at 10,000 rpm for 10 min. The precipitate was placed in an oven and heated and dried at 60° C. for 4 h. 5.07 g of white powder was obtained by grinding, i.e., blue afterglow material powder. The material cost was 0.15 yuan / g and the yield was 35.4%.

[0045] 2. Structural identification

[0046] Electron microscope images of aqueous blue afterglow materials are shown in Figure 2 As shown, the morphology of the synthesized A1-S1@SiO2 was characterized by 120kV transmission electron microscopy and the average particle size of the silicon spheres was 11nm.

[0047] The fluorescence spectrum of the aqueous blue afterglow material at 400-650nm was detected by fluorescence spectrometer. Figure 3 As shown, the fluorescence of A1-S1@SiO2, A2-S2@SiO2, and A3-S3@SiO2 is blue, and A4-S4@SiO2 has a double peak superposition showing cyan blue.

[0048] Use a phosphorescence spectrometer to detect the afterglow spectrum of the aqueous blue afterglow material at 400-650nm, see Figure 4 As shown, the maximum emission peak of A1-S1@SiO2 is 421nm, the maximum emission peak of A2-S2@SiO2 is 516nm, the maximum emission peak of A3-S3@SiO2 is 542nm, and the maximum emission peak of A4-S4@SiO2 is 617nm.

[0049] The UV-visible absorption spectrum of the aqueous blue afterglow material was measured using a UV-visible spectrophotometer. Figure 5 As shown in the figure, it can be seen that there are two ultraviolet characteristic absorption peaks at 241nm and 304nm, which are mainly attributed to the π-π* transition of C=C and the n-π* transition of C=O.

[0050] Use infrared spectrometer to detect the infrared spectrum of water-phase blue afterglow material. Figure 6 As shown in the figure, 1600cm -1 The strong absorption peaks on the left and right are attributed to the stretching vibration of C=O; 1360cm -1 The strong absorption peaks around 1100cm are attributed to CN stretching vibration; -1 The strong and broad absorption peak at A1-S1@SiO2 is attributed to the stretching vibration of Si-O. The Si-O peak at A1-S1@SiO2 is stronger than that at A1-S1, proving that the silica network structure formed by the hydrolysis of TEOS covers A1-S1.

[0051] Example 2: Green organic afterglow material

[0052] Reference Figure 1 , prepared as follows:

[0053] (1) Organic fluorescent molecule solution: At room temperature (25-30°C), reagent A2 (1.5 mmol 2,3-naphthalic anhydride, 2 μL propylene diamine, 0.5 mmol urea) was added to 10 mL of 50% ethanol aqueous solution, and ultrasonically mixed until completely dissolved. Then reagent S2 (18 μL (3-aminopropyl) trimethoxysilane, 10 μL 1-[3-(triethoxysilyl) propyl] urea) was added; ultrasonic mixing was continued, and the mixture was heated under reflux at 100°C for 6 h to obtain 10 mL of organic fluorescent molecule solution, which was recorded as A2-S2;

[0054] (2) Aqueous green afterglow material: 100 mL of deionized water, 2 mL of ammonia water, and 15 mL of tetraethyl silicate (TEOS) were directly added to 10 mL of A2-S2 obtained in step (1), and refluxed at 100°C for 5 h for siliconization treatment; after the reflux, the solution was naturally cooled to room temperature to obtain 127 mL of a slightly white solution, i.e., a green afterglow material solution, which was recorded as A2-S2@SiO2. The fluorescence spectrum of the aqueous green afterglow material at 400-650 nm is shown in Figure 3 As shown, the afterglow spectrum of 400-650nm is Figure 4 shown.

[0055] (3) Solid-phase green afterglow material: The green afterglow material solution in step (2) was centrifuged at 10,000 rpm for 10 min in a centrifuge, and the precipitate was placed in an oven and heated and dried at 60° C. for 4 h. 4.09 g of white powder was obtained by grinding, with an average particle size of 9 nm, i.e., green afterglow material powder. The material cost was 0.64 yuan / g, and the yield was 28.5%.

[0056] Example 3: Yellow organic afterglow material

[0057] Reference Figure 1 , prepared as follows:

[0058] (1) Organic fluorescent molecules: At room temperature (25-30°C), reagent A3 (1.5 mmol 1,8-naphthalene dicarboxylic anhydride, 5 μL maleic anhydride) was added to 10 mL of 50% ethanol aqueous solution, and ultrasonically mixed until completely dissolved. Then reagent S3 (18 μL (3-aminopropyl) trimethoxysilane, 10 μL N-(trimethylsilylmethyl) benzylamine) was added; ultrasonic mixing was continued, and the mixture was heated under reflux at 100°C for 6 h to obtain 10 mL of organic fluorescent molecule solution, which was recorded as A3-S3;

[0059] (2) Aqueous yellow afterglow material: 100 mL of deionized water, 2 mL of ammonia water, and 15 mL of tetraethyl silicate (TEOS) were directly added to 10 mL of A3-S3 obtained in step (1), and refluxed at 100°C for 5 h for siliconization treatment; after reflux, the solution was naturally cooled to room temperature to obtain 127 mL of a slightly white solution, i.e., a yellow afterglow material solution, which was recorded as A3-S3@SiO2. The fluorescence spectrum of the aqueous yellow afterglow material at 400-650 nm is shown in Figure 3 As shown, the afterglow spectrum of 400-650nm is Figure 4 shown.

[0060] (3) Solid-phase yellow afterglow material: The yellow afterglow material solution in step (2) was centrifuged at 10,000 rpm for 10 min in a centrifuge, and the precipitate was placed in an oven and heated and dried at 60° C. for 4 h. 5.88 g of white powder was obtained after grinding, with an average particle size of 11 nm, i.e., yellow afterglow material powder. The material cost was 0.13 yuan / g, and the yield was 41%.

[0061] Example 4: Red organic afterglow material

[0062] Reference Figure 1 , prepared as follows:

[0063] (1) Organic fluorescent molecules: At room temperature (25-30°C), reagent A4 (1.5 mmol 1,4,5,8-naphthalenetetracarboxylic anhydride, 0.1 mmol o-phenylenediamine, 5 μL ethylenediamine) was added to 10 mL of 50% ethanol aqueous solution, and ultrasonically mixed until completely dissolved. Then, 1 mmol reagent S4 (18 μL (3-aminopropyl)trimethoxysilane, 18 μL 3-(2-aminoethylamino)propyltriethoxysilane) was added. Ultrasonic mixing was continued, and the mixture was heated under reflux at 100°C for 6 h to obtain 10 mL of organic fluorescent molecule solution, which was recorded as A4-S4.

[0064] (2) Aqueous red afterglow material: 100 mL of deionized water, 2 mL of ammonia water, and 15 mL of tetraethyl silicate (TEOS) were directly added to 10 mL of A4-S4 obtained in step (1), and refluxed at 100°C for 5 h for siliconization treatment; after reflux, the solution was naturally cooled to room temperature to obtain 127 mL of a slightly white solution, i.e., a red afterglow material solution, denoted as A4-S4@SiO2. The fluorescence spectrum of the aqueous red afterglow material at 400-650 nm is shown in Figure 3 As shown, the afterglow spectrum of 400-650nm is Figure 4 shown.

[0065] (3) Solid-phase red afterglow material: The red afterglow material solution of step (2) was centrifuged at 10,000 rpm for 10 min. The precipitate was placed in an oven and heated and dried at 60° C. for 4 h. 8.27 g of white powder was obtained by grinding. The average particle size was 10 nm, i.e., red afterglow material powder. The material cost was 0.13 yuan / g and the yield was 57.6%.

[0066] Example 5: Multicolor afterglow material applied to pattern anti-counterfeiting

[0067] like Figure 7 As shown, the blue, green, yellow and red afterglow material solutions prepared in Examples 1-4 were respectively coated on white paper strips. After irradiation with a 365nm ultraviolet lamp, the paper showed blue fluorescence, and the encrypted information could not be distinguished. After turning off the 365nm excitation light, as time goes by, the red color disappears first, followed by the blue color, then the yellow color, and finally the green color remains. The blue afterglow can reach 5s, the green afterglow can reach 7s, the yellow afterglow can reach 6s, and the red afterglow can reach 0.5s.

[0068] like Figure 8 As shown, 5 mL of the blue, green, yellow, and red afterglow material solutions prepared in Examples 1-4 were taken, and the solution was dipped into a brush to smear and draw anti-counterfeiting patterns on white paper. After the solution dried, no pattern was seen on the white paper. After irradiation with a 365nm ultraviolet lamp, the fluorescence was blue, and after the ultraviolet lamp stopped irradiation, four different colors of afterglow appeared, and the disappearance time of different colors of afterglow was also different, red disappeared first, blue second, then yellow, and finally green. The afterglow disappeared over time to achieve pattern anti-counterfeiting.

[0069] Example 6: Multicolor afterglow material applied to LED light strip

[0070] 1. Production of LED light strips

[0071] Reference Fig. 9 Method b: making an LED light strip: placing the multi-color afterglow nano material powder directly at the center of the LED chip of the ultraviolet light strip, and covering it with a lampshade, thereby obtaining the LED light strip, which has three bulbs to prevent errors.

[0072] (1) Blue LED light strip

[0073] The blue afterglow material powder prepared in Example 1 was taken out of the lampshade of the lamp strip, 0.025 g of powder was weighed, and it was directly placed at the center of the LED chip of the ultraviolet lamp strip, and the lampshade was covered to obtain a blue LED lamp strip.

[0074] (2) Green LED light strip

[0075] The green afterglow material powder described in Example 2 is taken out of the lampshade of the lamp strip, 0.025 g of powder is weighed, and it is directly placed at the center of the LED chip of the ultraviolet lamp strip, and the lampshade is covered to obtain a green LED lamp strip.

[0076] (3) Yellow LED light strip.

[0077] The yellow afterglow material powder described in Example 3 is taken out of the lampshade of the lamp strip, 0.025 g of powder is weighed, and it is directly placed at the center of the LED chip of the ultraviolet lamp strip, and the lampshade is covered to obtain a yellow LED lamp strip.

[0078] (4) Red LED light strip.

[0079] The red afterglow material powder described in Example 4 is removed from the lampshade of the lamp strip, 0.025 g of the powder is weighed, and placed directly on the center of the LED chip of the ultraviolet lamp strip, and covered with the lampshade to obtain a red LED lamp strip.

[0080] 2. Light strip detection

[0081] In a dark environment, at 12V, the light strip using different multi-color afterglow powders produces blue-violet light; in addition, when the voltage is turned off, the light strip displays afterglow of different colors, such as blue, green, red, and yellow. The afterglow spectrum data of each afterglow material solution in Examples 1-4 are imported into the CIE diagram, and the obtained coordinate chromaticity is consistent with the afterglow color of the light strip.

[0082] Example 7: Optimization of preparation conditions for multicolor afterglow materials

[0083] Taking Example 2 as an example, the conditions are optimized:

[0084] (1) Amount of organic fluorescent molecule raw materials: The input volume ratio of deionized water to A2-S2 in step (2) of Example 2 was changed to 100:0.1, 100:0.5, 100:5, 100:10, and 100:15. The other operations were the same. The fluorescence intensity increased with the increase of reactants, and the afterglow intensity first increased and then weakened. The afterglow was the strongest at 100:10. By comparing the afterglow lifespans of raw materials in different ratios, the ratio of 100:10 was selected after comprehensive consideration.

[0085] (2) Reaction temperature: The temperature of the silicon coating reaction in step (2) of Example 2 was increased from 60°C to 120°C with a temperature increase of 10°C. Other operations were the same. The fluorescence intensity tended to increase, but after 120°C, the fluorescence intensity tended to decrease. Since the fluorescence difference was not large when the temperature changed, the afterglow intensity should be comprehensively considered. It first increased and then weakened with increasing temperature and was strongest at 100°C. Therefore, 100°C was selected as the optimal reaction temperature.

[0086] (3) Reaction time: The reaction time of the silicon coating in step (2) of Example 2 was changed to 1, 2, 3, 4, 5, 6, 7, or 8 h. The other operations were the same. The fluorescence intensity first increased and then decreased with time. When the time was 6 h, the fluorescence intensity was the strongest. Considering the afterglow intensity comprehensively, 6 h was selected as the optimal reaction time.

[0087] (4) Amount of TEOS: The amount of TEOS added in step (2) of Example 2 was changed to 1, 5, 10, 15, and 20 mL. The other operations remained the same. A small amount of TEOS was not enough to form silicon spheres of appropriate size to encapsulate the organic fluorescent molecules, while too much TEOS would result in silicon spheres that were too large, which would not only weaken the afterglow of the afterglow material but also affect the dispersibility of AS@SiO2 in water. Considering the afterglow intensity and dispersibility of the carbon dots in water, 15 mL of TEOS was finally selected as the optimal amount.

[0088] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A one-pot method for synthesizing a large amount of aqueous multi-color organic afterglow nanomaterials, characterized in that: The method comprises the following steps: (1) Organic fluorescent molecule solution: At room temperature, reagent A is added to an ethanol aqueous solution and ultrasonically mixed; then reagent S is added, ultrasonically mixed, and heated under reflux at 60-120° C. for 1-8 h to obtain an organic fluorescent molecule solution; The reagent A is selected from one or more of an acid compound, an anhydride compound or an amine compound; the acid compound includes: succinic acid, 1,4-naphthalene dicarboxylic acid, 2-carboxypyrene; the anhydride compound includes: butyric anhydride, isobutyric anhydride, maleic anhydride, succinic anhydride, glutaric anhydride, 2,3-pyridine dicarboxylic anhydride, 1,2-naphthalene dicarboxylic anhydride, phthalic anhydride, 1,8-naphthalene dicarboxylic anhydride or more; the amine compound includes: ethylenediamine One or more of 1-[3-(triethoxysilyl)propyl]urea, (3-aminopropyl)trimethoxysilane, N-(trimethylsilylmethyl)benzylamine, 3-(2-aminoethylamino)propyltriethoxysilane; (2) Aqueous multicolor organic afterglow nanomaterials: deionized water, ammonia water, and tetraethyl silicate are added to the organic fluorescent molecule solution obtained in step (1), and the mixture is heated to reflux at 60-120° C. for 1-8 hours. After the reflux is completed, the mixture is naturally cooled to room temperature to obtain an aqueous solution of a multicolor afterglow nanomaterial, i.e., an aqueous multicolor organic afterglow nanomaterial.

2. The method according to claim 1, characterized in that Step (1) Reagent A is composed of anhydride compounds and / or amine compounds; the anhydride compounds are selected from one or more of 2,3-pyridinedicarboxylic anhydride, 2,3-naphthalene dicarboxylic anhydride, 1,8-naphthalene dicarboxylic anhydride, maleic anhydride or 1,4,5,8-naphthalenetetracarboxylic anhydride; the amine compounds are selected from one or more of propylene diamine, propylene glycol, urea, o-phenylenediamine and ethylenediamine.

3. The method according to claim 1, characterized in that In step (1), the reagent S is selected from one or two of (3-aminopropyl)trimethoxysilane 1-[3-(triethoxysilyl)propyl]urea, N-(trimethylsilylmethyl)benzylamine, and 3-(2-aminoethylamino)propyltriethoxysilane.

4. The method according to claim 1, characterized in that Step (1) Reagent A is composed of one of the following: (1) 2,3-pyridinedicarboxylic anhydride and propylenediamine; (2) 2,3-naphthalene dicarboxylic anhydride, propylenediamine and urea; (3) 1,8-naphthalene dicarboxylic anhydride and maleic anhydride; (4) 1,4,5,8-naphthalenetetracarboxylic anhydride, o-phenylenediamine and ethylenediamine.

5. The method according to claim 1, characterized in that Step (1) The volume concentration of ethanol aqueous solution is 20-100%.

6. The method according to claim 1, characterized in that Step (1) The organic fluorescent molecule solution is prepared according to one of the following ratios: ① Reagent A is a mixture of 2,3-pyridinedicarboxylic anhydride and propylenediamine at a ratio of 1.5mmol:2μL; Reagent S is a mixture of (3-aminopropyl)trimethoxysilane and N-(trimethylsilylmethyl)benzylamine) at a volume ratio of 1.8:1; the volume amount of reagent S is 28μL / 1.5mmol based on the amount of 2,3-pyridinedicarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 2,3-pyridinedicarboxylic anhydride; ② Reagent A is a mixture of 2,3-naphthalene dicarboxylic anhydride, propylene diamine, and urea at a ratio of 1.5mmoL: 2μL: 0.5mmoL; Reagent S is a mixture of (3-aminopropyl) trimethoxysilane and 1-[3-(triethoxysilyl)propyl] urea) at a volume ratio of 1.8:1; the volume amount of reagent S is 28μL / 1.5mmol based on the amount of 2,3-pyridine dicarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 2,3-pyridine dicarboxylic anhydride; ③ Reagent A is a mixture of 1,8-naphthalene dicarboxylic anhydride and maleic anhydride at a ratio of 1.5mmoL:5μL; Reagent S is a mixture of (3-aminopropyl)trimethoxysilane and N-(trimethylsilylmethyl)benzylamine at a volume ratio of 1.8:1; the volume amount of reagent S is 28μL / 1.5mmol based on the amount of 1,8-naphthalene dicarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 1,8-naphthalene dicarboxylic anhydride; ④ Reagent A is a mixture of 1,4,5,8-naphthalenetetracarboxylic anhydride, o-phenylenediamine, and ethylenediamine in a ratio of 1.5mmoL:0.1mmoL:5μL; Reagent S is a mixture of (3-aminopropyl)trimethoxysilane and 3-(2-aminoethylamino)propyltriethoxysilane in a volume ratio of 1:1; the volume amount of reagent S is 36μL / 1.5mmol based on the amount of 1,4,5,8-naphthalenetetracarboxylic anhydride; the volume amount of ethanol aqueous solution is 10mL / 1.5mmol based on the amount of 1,4,5,8-naphthalenetetracarboxylic anhydride.

7. The method according to claim 1, characterized in that In step (2), the volume ratio of the organic fluorescent molecule solution to deionized water is 1:5-15; the volume ratio of the organic fluorescent molecule solution to ammonia water is 1:0.1-1; and the volume ratio of the organic fluorescent molecule solution to tetraethyl silicate is 1:1-3.

8. The method according to claim 1, characterized in that Step (1) reflux at 100°C for 6 hours; step (2) reflux at 100°C for 5 hours.

9. An aqueous multicolor organic afterglow nanomaterial prepared by the method of claim 1.

10. Use of an aqueous multicolor organic afterglow nanomaterial prepared by the method of claim 1.

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