Photo-temperature dual-response fluorescent photonic crystal composite material and preparation method thereof

Abstract

The invention discloses a preparation method of a light and temperature dual-response fluorescent photonic crystal composite material. The preparation method comprises the following steps: preparation of gold nanorods, preparation of quantum dots, preparation of a light response polymer, preparation of temperature response hydrogel, preparation of a photonic crystal template and preparation of the composite material. The light and temperature dual-response fluorescent photonic crystal composite material has light and temperature response and fluorescence performance, has important research value and application prospect, and is expected to realize innovative application in multiple fields of biomedicine, photoelectric devices, environment monitoring and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of materials, and particularly relates to a light-temperature dual-responsive fluorescent photonic crystal composite material and a preparation method thereof. Background Art

[0002] Stimulus-responsive actuators are a class of materials that can sense external stimuli, convert the stimulus signals into their own physical or chemical changes, and then generate driving behaviors. They have attracted much attention in the field of intelligent materials and play an important role in the development of modern technology. Common stimulus response types include light response, temperature response, pH response, electrical response, etc. Among them, light-responsive actuators achieve driving by absorbing light of a specific wavelength to cause internal structural changes in the material, while temperature-responsive actuators achieve driving based on the phase transition characteristics of the material at different temperatures. However, most current stimulus-responsive actuators can only respond to a single stimulus, which has great limitations. Therefore, the development of multi-stimulus-responsive actuators has become an important research field. Summary of the Invention

[0003] To solve the above technical problems, the technical solution adopted by the present invention is: a preparation method of a light-temperature dual-responsive fluorescent photonic crystal composite material, comprising the following steps:

[0004] Step 1: Preparation of gold nanorods. Dissolve a certain amount of cetyltrimethylammonium bromide in deionized water, then add a certain amount of chloroauric acid, stir evenly, and quickly add a certain amount of sodium borohydride solution. Stir and react for a period of time under ice bath conditions to obtain a seed solution; dissolve a certain amount of cetyltrimethylammonium bromide, silver nitrate, and chloroauric acid in deionized water in sequence, add a certain amount of ascorbic acid, and stir until the solution becomes colorless to obtain a growth solution; add a certain amount of the seed solution to the growth solution and react at a constant temperature for a certain time to obtain gold nanorods;

[0005] Step 2: Preparation of quantum dots. Under the protection of an inert gas, dissolve a certain amount of selenium powder in trioctylphosphine to form a selenium source solution; dissolve a certain amount of cadmium source in an organic solvent, then mix it with the selenium source solution, and then carry out a thermal injection reaction under high temperature conditions. After the reaction, centrifuge and wash repeatedly to obtain quantum dots;

[0006] Step 3: Preparation of a light-responsive polymer. Dissolve a certain amount of cinnamoyloxyethyl acrylate and azobisisobutyronitrile in an appropriate amount of toluene, introduce nitrogen to remove oxygen in the system, and stir and react at a certain temperature to obtain a light-responsive polymer;

[0007] Step 4: Preparation of temperature-responsive hydrogel. Dissolve a certain amount of N-isopropylacrylamide and N,N'-methylenebisacrylamide in deionized water, add a certain amount of ammonium persulfate and tetramethylethylenediamine, stir evenly, and react for a certain time under constant temperature conditions to obtain a temperature-responsive hydrogel;

[0008] Step 5: Preparation of photonic crystal template. Disperse polystyrene microspheres in an appropriate solvent and self-assemble them on a substrate by vertical deposition method to form an ordered photonic crystal template;

[0009] Step 6: Preparation of composite material. Disperse the prepared gold nanorods in an appropriate solvent to obtain a gold nanorod solution; disperse quantum dots in toluene to prepare a quantum dot solution; mix the gold nanorod solution and the quantum dot solution in a certain proportion, and perform ultrasonic treatment to make them evenly dispersed to obtain a gold nanorod-quantum dot mixed solution; dissolve the photo-responsive polymer in an appropriate organic solvent, then mix it evenly with the gold nanorod-quantum dot mixed solution, add the temperature-responsive hydrogel and mix evenly, and finally pour them all into a mold containing the photonic crystal template and cure and mold them to obtain a photo-thermo dual-responsive fluorescent photonic crystal composite material containing gold nanorod composite quantum dots.

[0010] As a preference of the above technical solution, in Step 1, add 50 mL of deionized water to a container, then weigh 0.182 g of cetyltrimethylammonium bromide and add it thereto, stir magnetically and heat to 30 °C to completely dissolve the cetyltrimethylammonium bromide, and prepare a cetyltrimethylammonium bromide solution with a concentration of 0.1 mol / L; after cooling to room temperature, add 5 mL of chloroauric acid solution with a concentration of 0.01 mol / L to the container, continuously stir for 15 minutes to make the solution evenly mixed; add 0.6 mL of sodium borohydride solution with a concentration of 0.01 mol / L, stir for 2 minutes under ice bath conditions, and let it stand at room temperature for 2 hours to obtain a seed solution;

[0011] Take another container, add 250 mL of deionized water, weigh 0.91 g of cetyltrimethylammonium bromide and 0.017 g of silver nitrate and add them thereto, stir and heat to 30 °C to completely dissolve; add 25 mL of chloroauric acid solution with a concentration of 0.01 mol / L, stir evenly, and then add 0.7 mL of ascorbic acid solution with a concentration of 0.1 mol / L to obtain a growth solution;

[0012] Add 0.4 mL of the above-prepared seed solution to the growth solution, stir evenly, and let it stand and react at 30 °C for 12 hours; after the reaction is completed, transfer the solution to a centrifuge tube, centrifuge at a speed of 10000 rpm for 20 minutes, discard the supernatant, redisperse the precipitate with deionized water, and centrifuge again, repeat this operation 3 times to remove excess surfactants and impurities, and finally obtain purified gold nanorods.

[0013] Preferably, in the second step, under the protection of inert gas N2, 0.830 g of trioctylphosphine is added as a solvent into a container, 0.024 g of selenium powder is added, and they are stirred evenly to form a selenium source solution with a concentration of 0.3 mol / L. Another container is taken, 0.136 g of cadmium oleate is dissolved in 4 ml of octadecene, and they are evenly mixed. Then it is mixed with the selenium source solution, and a thermal injection reaction is carried out under high temperature conditions. After the reaction is completed, it is transferred to a centrifuge tube, centrifuged at a speed of 10000 rpm for 10 minutes, the supernatant is discarded, washed with methanol, and centrifuged again. This operation is repeated 3 times to obtain quantum dots.

[0014] Preferably, in the third step, 50 mL of toluene is added as a solvent into a container, 5 g of cinnamoyloxyethyl acrylate monomer is added, and it is stirred to completely dissolve; 0.025 g of azobisisobutyronitrile is added as an initiator, and nitrogen is introduced into the container for 30 minutes to remove oxygen in the system; the container is placed in an oil bath at 70 °C and stirred for 6 hours. After the reaction is completed, the reaction solution is slowly dropped into a large amount of methanol to precipitate the polymer, then filtered, and the precipitate is washed 3 times with methanol. Finally, the precipitate is dried in a vacuum oven at 50 °C for 24 hours to obtain a light-responsive polymer.

[0015] Preferably, in the fourth step, 100 mL of deionized water is added into a container, 10 g of N-isopropylacrylamide and 0.1 g of N,N'-methylenebisacrylamide are weighed and added into the water, and it is stirred to completely dissolve; 1 mL of ammonium persulfate solution with a concentration of 0.1 mol / L and 1 mL of tetramethylethylenediamine solution with a concentration of 0.1 mol / L are added as an initiation system; after stirring evenly, the container is placed in a water bath at 50 °C and reacted for 4 hours. After the reaction is completed, the product is soaked in deionized water for 24 hours, and the deionized water is changed every 6 hours to remove unreacted monomers and impurities to obtain a temperature-responsive hydrogel.

[0016] Preferably, in the fifth step, 1 g of monodisperse polystyrene microspheres with a particle size of 200 nm is weighed and added into 50 mL of absolute ethanol, and it is ultrasonically dispersed for 30 minutes to form a uniform microsphere dispersion; a clean glass substrate is vertically immersed in the microsphere dispersion, and then it is placed in a closed container. In an environment with a temperature of 25 °C and a humidity of 50%, ethanol is slowly volatilized, and the microspheres self-assemble on the glass substrate to form a photonic crystal template; the self-assembly process lasts for 24 hours. After the ethanol is completely volatilized, the glass substrate is taken out of the container to obtain a photonic crystal template.

[0017] Preferably, in the sixth step, the prepared gold nanorods are diluted with deionized water to a concentration of 1×10-5 mol / L; Take 10 mL of the gold nanorod solution and place it in a container. Dilute the prepared quantum dots with n - hexane to a concentration of 5×10 -6 mol / L. Take 5 mL of this solution and add it to the container with the gold nanorod solution. Ultrasonically mix for 15 minutes to uniformly disperse the gold nanorods and quantum dots. Add 0.5 g of the light - responsive polymer and stir until it completely dissolves. Cut the temperature - responsive hydrogel after the soaking treatment into small pieces, add them to the container, and stir evenly to allow the hydrogel to fully absorb the components in the solution. Transfer the hydrogel to a mold containing a photonic crystal template and cure it in an oven at 60 °C for 24 hours to further cross - link the hydrogel. At the same time, fix the gold nanorods, quantum dots, and photonic crystal template in the hydrogel layer, and finally obtain a photo - thermo dual - responsive fluorescent photonic crystal composite material containing gold nanorod - composite quantum dots.

[0018] The photo - thermo dual - responsive fluorescent photonic crystal composite material is prepared by the above - mentioned preparation method.

[0019] The beneficial effects of the present invention are as follows: The present invention uses cinnamoyloxyethyl acrylate as a reaction monomer to construct a dynamic transesterification network as the light - responsive component, which has more excellent light - responsive characteristics, an adjustable dynamic network structure, and compatibility and synergy with other materials.

[0020] In the temperature - responsive drive, the present invention utilizes the photothermal effect of gold nanorods. Gold nanorods can efficiently convert light energy into heat energy after absorbing light, thereby realizing the regulation of the surrounding environmental temperature. The selection of hydrogel as the carrier for temperature response is because the hydrogel has a good thermal expansion effect. When the temperature changes, the hydrogel will undergo a volume change, and this volume change can be used as the driving power source.

[0021] Introducing the photonic crystal structure can further improve the performance of the actuator. Photonic crystals have a periodic dielectric structure that can regulate the propagation of light. Introducing the photonic crystal structure can not only improve the driving performance but also endow the material with structural color, making it present a unique optical effect in appearance. Adding quantum dots enables the material to have the performance of fluorescence drive. Quantum dots are a type of semiconductor nanocrystal with size - dependent fluorescence emission characteristics. Their fluorescence emission spectrum is narrow and bright, and they can emit strong fluorescence when excited by light, adding a new functional dimension to the actuator.

[0022] The photo - thermo dual - responsive fluorescent photonic crystal composite material of the present invention, a composite material with light, temperature - responsive, and fluorescence properties, has important research value and application prospects, and is expected to achieve innovative applications in multiple fields such as biomedicine, optoelectronic devices, and environmental monitoring. Description of the Drawings

[0023] Figure 1It is the SEM image of the photo-thermo dual-responsive fluorescent photonic crystal composite material prepared in Example 1;

[0024] Figure 2 It is the XRD pattern of the photo-thermo dual-responsive fluorescent photonic crystal composite material prepared in Example 1;

[0025] Figure 3 It is the light intensity-response time curve graph of the photo-thermo dual-responsive fluorescent photonic crystal composite materials prepared in each example;

[0026] Figure 4 It is the temperature-optical property curve graph of the photo-thermo dual-responsive fluorescent photonic crystal composite materials prepared in each example;

[0027] Figure 5 It is the fluorescence property comparison graph of the photo-thermo dual-responsive fluorescent photonic crystal composite material. Detailed implementation manners

[0028] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts fall within the protection scope of the present invention.

[0029] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0030] Example 1

[0031] Add 50 mL of deionized water into a container, then weigh 0.182 g of cetyltrimethylammonium bromide and add it thereto. Stir magnetically and heat to 30 °C to completely dissolve the cetyltrimethylammonium bromide, and prepare a cetyltrimethylammonium bromide solution with a concentration of 0.1 mol / L; after cooling to room temperature, add 5 mL of chloroauric acid solution with a concentration of 0.01 mol / L to the container, and continuously stir for 15 minutes to make the solution evenly mixed; add 0.6 mL of sodium borohydride solution with a concentration of 0.01 mol / L, stir for 2 minutes under ice bath conditions, and let it stand at room temperature for 2 hours to obtain a seed solution;

[0032] Take another container, add 250 mL of deionized water, weigh 0.91 g of cetyltrimethylammonium bromide and 0.017 g of silver nitrate and add them thereto, stir and heat to 30 °C until completely dissolved; add 25 mL of chloroauric acid solution with a concentration of 0.01 mol / L, stir evenly, and then add 0.7 mL of ascorbic acid solution with a concentration of 0.1 mol / L to obtain a growth solution;

[0033] Add 0.4 mL of the above-prepared seed solution to the growth solution, stir evenly, and leave it standing for reaction at 30 °C for 12 hours; after the reaction is completed, transfer the solution to a centrifuge tube, centrifuge at a speed of 10000 rpm for 20 minutes, discard the supernatant, redisperse the precipitate with deionized water, centrifuge again, and repeat this operation 3 times to remove excess surfactants and impurities, and finally obtain purified gold nanorods.

[0034] Under the protection of inert gas N2, add 0.830 g of trioctylphosphine as a solvent to the container, add 0.024 g of selenium powder, stir evenly to form a selenium source solution with a concentration of 0.3 mol / L; take another container, dissolve 0.136 g of cadmium oleate in 4 ml of octadecene, mix evenly, and then mix with the selenium source solution, and carry out a thermal injection reaction under high-temperature conditions. After the reaction is completed, transfer it to a centrifuge tube, centrifuge at a speed of 10000 rpm for 10 minutes, discard the supernatant, wash with methanol, centrifuge again, and repeat this operation 3 times to obtain quantum dots.

[0035] Add 50 mL of toluene as a solvent to another container, add 5 g of cinnamoyloxyethyl acrylate monomer, and stir until completely dissolved; add 0.025 g of azobisisobutyronitrile as an initiator, and introduce nitrogen into the container for 30 minutes to remove oxygen in the system; place the container in an oil bath at 70 °C and stir for reaction for 6 hours. After the reaction is completed, slowly drop the reaction solution into a large amount of methanol to precipitate the polymer, then filter, wash the precipitate with methanol 3 times, and finally dry the precipitate in a vacuum oven at 50 °C for 24 hours to obtain a light-responsive polymer.

[0036] Add 100 mL of deionized water to another container, weigh 10 g of N-isopropylacrylamide and 0.1 g of N,N'-methylenebisacrylamide and add them to the water, and stir until completely dissolved; add 1 mL of ammonium persulfate solution with a concentration of 0.1 mol / L and 1 mL of tetramethylethylenediamine solution with a concentration of 0.1 mol / L as an initiation system; after stirring evenly, place the container in a water bath at 50 °C for reaction for 4 hours. After the reaction is completed, soak the product in deionized water for 24 hours, and change the deionized water every 6 hours to remove unreacted monomers and impurities to obtain a temperature-responsive hydrogel.

[0037] Weigh 1 g of monodisperse polystyrene microspheres with a particle size of 200 nm, add them to 50 mL of absolute ethanol, and ultrasonically disperse for 30 minutes to form a uniform microsphere dispersion; vertically immerse a clean glass substrate into the microsphere dispersion, and then place it in a closed container. In an environment with a temperature of 25 °C and a humidity of 50%, allow the ethanol to slowly evaporate, and the microspheres self-assemble on the glass substrate to form a photonic crystal template; the self-assembly process lasts for 24 hours. After the ethanol has completely evaporated, take out the glass substrate from the container to obtain the photonic crystal template.

[0038] Dilute the prepared gold nanorods with deionized water to a concentration of 1×10 -5 mol / L; take 10 mL of the gold nanorod solution and place it in a container. Dilute the prepared quantum dots with n-hexane to a concentration of 5×10 -6 mol / L, take 5 mL of this solution and add it to the container containing the gold nanorod solution, and ultrasonically mix for 15 minutes to uniformly disperse the gold nanorods and quantum dots; add 0.5 g of the light-responsive polymer and stir until it completely dissolves; cut the temperature-responsive hydrogel after the immersion treatment into small pieces, add them to the container, and stir evenly to allow the hydrogel to fully absorb the components in the solution; transfer the hydrogel to a mold containing the photonic crystal template, and cure it in an oven at 60 °C for 24 hours to further crosslink the hydrogel, and at the same time fix the gold nanorods, quantum dots, and photonic crystal template in the hydrogel layer, and finally obtain a photo-thermo dual-responsive fluorescent photonic crystal composite material containing gold nanorod composite quantum dots.

[0039] Example 2

[0040] The remaining steps are the same as those in Example 1. The difference lies in that the concentration of the gold nanorod solution is changed from 1×10 -5 mol / L to 2×10 -5 mol / L.

[0041] Example 3

[0042] The remaining steps are the same as those in Example 1. The difference lies in that the concentration of the quantum dots is changed from 5×10 -6 mol / L to 1×10 -5 mol / L.

[0043] Example 4

[0044] The remaining steps are the same as those in Example 1. The difference lies in that the amount of the light-responsive polymer is changed from 0.5 g to 1 g.

[0045] Example 5

[0046] The remaining steps are the same as those in Example 1. The difference lies in that the amount of NIPAM in the temperature-responsive hydrogel is changed from 10 g to 12 g.

[0047] The SEM image of the photo-thermo dual-responsive fluorescent photonic crystal composite material prepared in Example 1 is as follows Figure 1 shown. From Figure 1 it, the microstructure of the composite material can be intuitively seen. The phase distribution in the figure is uniform, indicating that the preparation process enables the components to be well mixed. Due to its special optical properties, gold nanorods exhibit a specific contrast in the SEM image, and some regions with higher brightness are observed; due to their smaller size, quantum dots are distributed in the gaps between other phases or are tightly combined with them. The sizes of each phase can be measured, and from this, the influence of the different sizes of each phase on the properties of the composite material can be inferred. For example, larger gold nanorods have higher light absorption ability and photothermal conversion efficiency; the particle size of quantum dots determines their fluorescence emission wavelength and intensity, and quantum dots with different particle sizes emit different colors of fluorescence. In addition, the morphological characteristics of each phase can be observed, reflecting the influence of the preparation process on the microstructure of the material.

[0048] The XRD pattern of the photo-thermo dual-responsive fluorescent photonic crystal composite material prepared in Example 1 is as follows Figure 2 shown. From Figure 2 it, the information on the internal crystal structure of the material can be reflected through diffraction peaks at different angles. The sharp and obvious diffraction peaks appearing in the pattern indicate that there are substances with good crystallinity in the composite material. For example, the common crystal structure of gold nanorods is face-centered cubic, and a corresponding diffraction peak appears at about 38°. By observing the intensity of the peak at this position, the relative content of each phase can be judged. The higher the peak intensity, usually the relatively higher the content of this component in the material.

[0049] I. Characterization of optical driving performance

[0050] Using time-resolved spectroscopy technology, the response time from the start of illumination to the stable state of the optical performance is accurately measured to evaluate the optical driving response speed. Record the response times at different light intensities and plot the light intensity-response time curve, as follows Figure 3 shown.

[0051] From the overall change trend of the curve in the figure, as the light intensity increases, the response times of the materials in each example all show a downward trend, indicating that the light intensity has a significant influence on the time required for the optical performance of the composite material to reach a stable state. The higher the light intensity, the faster the material response speed, that is, there is a negative correlation between the light intensity and the response time.

[0052] Figure 3It contains five curves of Examples 1-5. Due to the different material formulation contents of each example, the curve positions and slopes are different. Specifically, in the figure, for Example 1, when the light intensity is 100%, the response time is the longest, and as the light intensity increases, the response time gradually decreases; for Example 2 compared to Example 1 at low light intensities, the response time is lower, but the amplitude of the decrease in its response time with the decrease in light intensity is smaller than that of Example 1; the curve decline trend of Example 3 is similar to that of other examples, but there are differences in the response time values at different light intensities. Since Example 3 changed the quantum dot concentration, the change in quantum dot concentration affects the electron transition process under light excitation and the interaction with other components, resulting in a change in the light response performance, and further making the response time show a unique change trend, showing that in the medium light intensity region (such as 140%-160% light intensity), the decline amplitude of the response time is relatively gentle; for Example 4, the amount of the light-responsive polymer increases, and more light-responsive polymers provide more light-responsive active sites, which can undergo structural changes more quickly under light action and accelerate the stabilization speed of the optical properties. The curve shows that when the light intensity changes by the same amplitude, the decline amplitude of the response time is larger; in Example 5, the amount of NIPAM in the temperature-responsive hydrogel changes, affecting the hydrogel network structure and thermal expansion properties, showing unique curve characteristics in the light intensity-response time relationship.

[0053] II. Temperature-driven Performance Test

[0054] Using a combined system of a hot stage and a photometer, the composite material was heated and tested to evaluate the sensitivity of temperature drive. The heating rate was set at 5°C / min, and the temperature range was 20 - 60°C. The reflected light intensity of the composite material at different temperatures was recorded, and a temperature-reflected light intensity curve was plotted, as Figure 4 shown.

[0055] Figure 4 shows the temperature-reflected light intensity curves of the light-temperature dual-responsive fluorescent photonic crystal composite materials of each example. It can be seen from the figure that as a whole, the curves all show a trend of gradually increasing reflected light intensity with the increase in temperature. This indicates that temperature has a significant impact on the reflected light intensity of this composite material. The increase in temperature promotes the internal structural changes of the material, thereby enhancing the reflected light intensity.

[0056] From Figure 4It can be seen that, as a reference curve, the reflected light intensity of Example 1 increases steadily with increasing temperature. The initial intensity is low, and as the temperature rises, the intensity gradually increases, and the growth trend is relatively stable, reflecting the change of the reflected light intensity of the material with temperature under the basic formula. Compared with Example 1, Example 2 has an overall lower reflected light intensity at the same temperature. Compared with Example 1, due to the increase in the concentration of quantum dots, the propagation path and interaction of light inside the material are affected, resulting in a relatively slow increase in the reflected light intensity during the temperature increase process. Its curve is similar to the other embodiments, but the increase in the reflected light intensity is relatively slow. Compared with Example 1, the amount of photoresponsive polymer used in Example 4 is increased, which optimizes the reflection mechanism of the internal structure of the material to light, resulting in the most significant increase in the reflected light intensity of the curve and the steepest upward trend. Compared with Example 1, the amount of NIPAM used in the temperature-responsive hydrogel in Example 5 is increased, which enhances the network structure and thermal expansion properties of the hydrogel, thereby affecting the material's reflection characteristics to light. During the temperature increase process, the effect of improving the reflected light intensity is worse than that of Example 1, but not as significant as that of Example 4.

[0057] 3. Fluorescence driving performance test

[0058] The fluorescence performance of the composite material was tested using a fluorescence spectrometer. The excitation light conditions were changed to observe the changes in fluorescence emission, evaluate the fluorescence driving effect, and study the effect of the interaction between gold nanorods and quantum dots on the fluorescence performance. The excitation light wavelength range was set to 300-500nm. The test results are as follows: Figure 5 shown.

[0059] Figure 5 The intensity-wavelength curves of composite photonic crystals and traditional photonic crystals are shown in Figure 2. Both curves show a trend of rising first and then falling, reaching an intensity peak at a certain wavelength, which shows that the two photonic crystals have selectivity in responding to light of different wavelengths. At a specific wavelength, the interaction between light and materials is the strongest, and the intensity produced is the highest. The peak intensity of the composite photonic crystal curve is significantly higher than that of the traditional photonic crystal. At the same wavelength position (indicated by a dotted line in the figure), the intensity of the composite photonic crystal can reach about 13,000 a.u., while the intensity of the traditional photonic crystal is about 8,000 a.u. This shows that the composite photonic crystal introduces new components and structures, changes the propagation and coupling characteristics of light, and makes its ability to capture and enhance light better than traditional photonic crystals. The composite photonic crystal curve is relatively sharper, which means that its intensity changes more dramatically near the peak wavelength and has a narrower selectivity for wavelengths, indicating that the composite photonic crystal responds more concentratedly and sensitively to light of a specific wavelength and can interact with light of a specific wavelength more accurately.

[0060] It is worth mentioning that the technical features such as the vacuum oven involved in this invention patent application should be regarded as the prior art. For the specific structures, working principles, and possibly involved control methods and spatial arrangement methods of these technical features, conventional selections in the art can be adopted, and they should not be regarded as the invention points of this invention patent. This invention patent will not be further elaborated specifically.

[0061] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in this technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. Preparation method of a light and temperature dual-responsive fluorescent photonic crystal composite material, characterized in that, It includes the following steps: Step 1: Preparation of gold nanorods. Dissolve a certain amount of cetyltrimethylammonium bromide in deionized water, then add a certain amount of chloroauric acid. After stirring evenly, quickly add a certain amount of sodium borohydride solution, and stir and react for a period of time under ice bath conditions to obtain a seed solution. Dissolve a certain amount of cetyltrimethylammonium bromide, silver nitrate and chloroauric acid in deionized water in sequence, add a certain amount of ascorbic acid, and stir until the solution becomes colorless to obtain a growth solution. Add a certain amount of the seed solution to the growth solution and react for a certain time under constant temperature conditions to obtain gold nanorods; Step 2: Preparation of quantum dots. Under the protection of inert gas, dissolve a certain amount of selenium powder in trioctylphosphine to form a selenium source solution. Dissolve a certain amount of cadmium source in an organic solvent, then mix it with the selenium source solution, and then carry out a thermal injection reaction under high temperature conditions. After the reaction ends, centrifuge and wash repeatedly to obtain quantum dots; Step 3: Preparation of photo-responsive polymer. Dissolve a certain amount of cinnamoyloxyethyl acrylate and azobisisobutyronitrile in an appropriate amount of toluene, pass nitrogen to remove oxygen in the system, and stir and react at a certain temperature to obtain a photo-responsive polymer; Step 4: Preparation of temperature-responsive hydrogel. Dissolve a certain amount of N-isopropylacrylamide and N,N'-methylenebisacrylamide in deionized water, add a certain amount of ammonium persulfate and tetramethylethylenediamine, stir evenly, and react for a certain time under constant temperature conditions to obtain a temperature-responsive hydrogel; Step 5: Preparation of photonic crystal template. Disperse polystyrene microspheres in an appropriate solvent and self-assemble on the substrate by vertical deposition method to form an ordered photonic crystal template; Step 6: Preparation of composite material. Disperse the prepared gold nanorods in an appropriate solvent to obtain a gold nanorod solution. Disperse the quantum dots in toluene to prepare a quantum dot solution. Mix the gold nanorod solution and the quantum dot solution in a certain proportion, and perform ultrasonic treatment to make them evenly dispersed to obtain a gold nanorod-quantum dot mixed solution. Dissolve the photo-responsive polymer in an appropriate amount of organic solvent, then mix it evenly with the gold nanorod-quantum dot mixed solution, add the temperature-responsive hydrogel and mix evenly. Finally, pour them all into a mold containing the photonic crystal template and cure and mold to obtain a photo-thermo dual-responsive fluorescent photonic crystal composite material containing gold nanorod composite quantum dots.

2. The preparation method of the light and temperature dual-responsive fluorescent photonic crystal composite material according to claim 1, wherein In the said Step 1, add 50 mL of deionized water to a container, then weigh 0.182 g of cetyltrimethylammonium bromide and add it thereto, stir magnetically and heat to 30 °C to completely dissolve cetyltrimethylammonium bromide and configure a cetyltrimethylammonium bromide solution with a concentration of 0.1 mol / L. After cooling to room temperature, add 5 mL of a 0.01 mol / L chloroauric acid solution to the container, continuously stir for 15 minutes to make the solution mix evenly. Add 0.6 mL of a 0.01 mol / L sodium borohydride solution, stir for 2 minutes under ice bath conditions, and let it stand at room temperature for 2 hours to obtain a seed solution; Take another container, add 250 mL of deionized water, weigh 0.91 g of cetyltrimethylammonium bromide and 0.017 g of silver nitrate and add them thereto, stir and heat to 30 °C until completely dissolved; add 25 mL of chloroauric acid solution with a concentration of 0.01 mol / L, stir evenly, and then add 0.7 mL of ascorbic acid solution with a concentration of 0.1 mol / L to obtain a growth solution; Add 0.4 mL of the above-prepared seed solution to the growth solution, stir evenly, and leave to react at 30 °C for 12 hours; after the reaction is completed, transfer the solution to a centrifuge tube, centrifuge at a speed of 10000 rpm for 20 minutes, discard the supernatant, redisperse the precipitate with deionized water, centrifuge again, and repeat this operation 3 times to remove excess surfactant and impurities, and finally obtain purified gold nanorods.

3. The preparation method of the photo-thermo dual-responsive fluorescent photonic crystal composite material according to claim 1, characterized in that, In the second step, under the protection of inert gas N2, add 0.830 g of trioctylphosphine as a solvent to a container, add 0.024 g of selenium powder, stir evenly to form a selenium source solution with a concentration of 0.3 mol / L; take another container, dissolve 0.136 g of cadmium oleate in 4 ml of octadecene, mix evenly, and then mix with the selenium source solution, and carry out a thermal injection reaction under high temperature conditions. After the reaction is completed, transfer it to a centrifuge tube, centrifuge at a speed of 10000 rpm for 10 minutes, discard the supernatant, wash with methanol, centrifuge again, and repeat this operation 3 times to obtain quantum dots.

4. The preparation method of the photo-thermo dual-responsive fluorescent photonic crystal composite material according to claim 1, characterized in that, In the third step, add 50 mL of toluene as a solvent to a container, add 5 g of cinnamoyloxyethyl acrylate monomer, and stir to completely dissolve it; add 0.025 g of azobisisobutyronitrile as an initiator, and pass nitrogen into the container for 30 minutes to remove oxygen in the system; place the container in an oil bath at 70 °C and stir and react for 6 hours. After the reaction is completed, slowly drop the reaction solution into a large amount of methanol to precipitate the polymer, then filter, wash the precipitate with methanol 3 times, and finally dry the precipitate in a vacuum oven at 50 °C for 24 hours to obtain a light-responsive polymer.

5. The preparation method of the photo-thermo dual-responsive fluorescent photonic crystal composite material according to claim 1, wherein, In the fourth step, add 100 mL of deionized water to a container, weigh 10 g of N-isopropylacrylamide and 0.1 g of N,N'-methylenebisacrylamide and add them to the water, and stir to completely dissolve them; add 1 mL of ammonium persulfate solution with a concentration of 0.1 mol / L and 1 mL of tetramethylethylenediamine solution with a concentration of 0.1 mol / L as an initiation system; after stirring evenly, place the container in a water bath at 50 °C and react for 4 hours. After the reaction is completed, soak the product in deionized water for 24 hours, and change the deionized water every 6 hours to remove unreacted monomers and impurities to obtain a temperature-responsive hydrogel.

6. The preparation method of the photo-thermo dual-responsive fluorescent photonic crystal composite material according to claim 1, wherein, In Step 5, weigh 1 g of monodisperse polystyrene microspheres with a particle size of 200 nm, add them to 50 mL of absolute ethanol, and ultrasonically disperse for 30 minutes to form a uniform microsphere dispersion; vertically immerse a clean glass substrate into the microsphere dispersion, and then place it in a sealed container. In an environment with a temperature of 25 °C and a humidity of 50%, allow the ethanol to slowly evaporate, and the microspheres self-assemble on the glass substrate to form a photonic crystal template; the self-assembly process lasts for 24 hours. After the ethanol has completely evaporated, take out the glass substrate from the container to obtain the photonic crystal template.

7. The preparation method of the photo-thermo dual-responsive fluorescent photonic crystal composite material according to claim 1, wherein, In the sixth step, the prepared gold nanorods are diluted with deionized water to a concentration of 1×10 -5 mol / L; 10 mL of the gold nanorod solution is placed in a container, and the prepared quantum dots are diluted with n-hexane to a concentration of 5×10 -6 mol / L. 5 mL of this solution is added to the container containing the gold nanorod solution, and ultrasonic mixing is carried out for 15 minutes to uniformly disperse the gold nanorods and quantum dots; 0.5 g of the light-responsive polymer is added and stirred until it is completely dissolved; the temperature-responsive hydrogel after the soaking treatment is cut into small pieces and added to the container, and stirred evenly to make the hydrogel fully absorb the components in the solution; the hydrogel is transferred to a mold containing a photonic crystal template and cured in an oven at 60 °C for 24 hours to further crosslink the hydrogel, and at the same time, the gold nanorods, quantum dots, and photonic crystal template are fixed in the hydrogel layer, and finally, a photo-thermo dual-responsive fluorescent photonic crystal composite material containing gold nanorod composite quantum dots is obtained.

8. A light and temperature dual-responsive fluorescent photonic crystal composite material, characterized in that, Prepared by the preparation method according to any one of Claims 1-7.

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