Luminescent material with aggregation-induced emission, thermochromic and photochromic properties as well as preparation method and application thereof

Abstract

The invention provides a luminescent material with aggregation-induced emission, thermochromic and photochromic properties as well as a preparation method and application thereof, and belongs to the technical field of photoresponse materials. The luminescent material provided by the invention almost has no photoluminescence phenomenon in a pure DMSO solvent, but emits strong cyan light once in an aggregation state, and the aggregation-induced emission effect is extremely obvious; from the aspect of temperature response characteristics, the luminescent material is blue in a low-temperature environment of 77K, is turquoise under a room-temperature condition, shows different optical properties at different temperatures, and is remarkable in thermoluminescence discoloration effect; meanwhile, the solid powder of the luminescent material initially shows turquoise luminescence, after the solid powder is irradiated by 365nm ultraviolet light for 2 minutes, the turquoise luminescence can be converted into blue luminescence, and the photoluminescence discoloration effect is outstanding.

Description

Technical Field

[0001] The present invention relates to the technical field of photo-responsive materials, and in particular, to a luminescent material having aggregation-induced emission, thermochromic and photochromic properties, a preparation method thereof, and an application thereof. Background Art

[0002] When traditional luminescent materials aggregate in the condensed phase, the emission is usually partially or completely quenched, showing the aggregation-caused quenching (ACQ) phenomenon, which greatly limits the practical applications of fluorophores. Organic luminescent materials, due to their aggregation-induced emission (AIE) characteristics, thermochromic and photofluorescent color-changing properties, have attracted extensive attention due to their great potential in fields such as temperature sensing, optoelectronic devices, and anti-counterfeiting applications. These AIE luminogens are weakly emissive or non-emissive in solution, but show strong emission when aggregates are formed, which is opposite to the ACQ effect. Compounds with aggregation-induced emission effect have very strong solid-state luminescence, which is helpful for the practical application of fluorescent color-changing materials. In addition, organic luminescent materials have good thermochromic and photochromic properties. Under the stimulation of the external environmental temperature and light, their optical properties change and are very sensitive to the changes in external temperature and light, so they can be widely used in the fields of sensors and information storage devices. However, among the organic complex materials that have been reported so far, those with aggregation-induced emission effect, thermochromism and photochromism at the same time are very rare.

[0003] Therefore, providing a luminescent material with aggregation-induced emission, thermochromic and photochromic properties at the same time has become an urgent technical problem in this field. Summary of the Invention

[0004] The purpose of the present invention is to provide a luminescent material having aggregation-induced emission, thermochromic and photochromic properties, a preparation method thereof, and an application thereof. The method provided by the present invention eliminates due to degree.

[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0006] The present invention provides a luminescent material having aggregation-induced emission, thermochromic and photochromic properties, and its structure is shown in Formula I:

[0007]

[0008] The present invention provides a preparation method of the luminescent material having aggregation-induced emission, thermochromic and photochromic properties as described in the above technical solution, including the following steps:

[0009] (1) Mix carbazole trimer, p-iodoacetanilide, cuprous oxide and N,N-dimethylacetamide, carry out Ullmann reaction, and then add dilute sulfuric acid for hydrolysis reaction to obtain an amino-containing compound;

[0010] (2) Mix the amino compound obtained in the step (1) with formic acid and carry out a formylation reaction to obtain a compound containing a formamide unit;

[0011] (3) Mix the compound containing a formamide unit obtained in the step (2) with triphosgene, triethylamine and a first solvent and carry out a dehydration reaction to obtain a compound containing an isocyan unit;

[0012] (4) Mix the compound containing an isocyan unit obtained in the step (3) with Au(C6F5)(tht) and a second solvent and carry out a coordination reaction to obtain a luminescent material with aggregation-induced emission, thermochromic and photochromic properties.

[0013] Preferably, the molar ratio of the carbazole trimer to p-iodoacetanilide in the step (1) is 1:(1 - 1.1).

[0014] Preferably, the temperature of the Ullmann reaction in the step (1) is 180 - 200 °C, the time of the Ullmann reaction is 24 - 26 h, and the Ullmann reaction is carried out under reflux stirring conditions.

[0015] Preferably, the molar ratio of the amino compound to formic acid in the step (2) is preferably 1:(200 - 300).

[0016] Preferably, the temperature of the formylation reaction in the step (2) is 101 - 110 °C, the time of the formylation reaction is 8 - 10 h, and the formylation reaction is carried out under reflux stirring conditions.

[0017] Preferably, the molar ratio of the compound containing a formamide unit to triphosgene in the step (3) is 1:(1.1 - 1.2).

[0018] Preferably, the temperature of the dehydration reaction in the step (3) is 50 - 60 °C, the time of the dehydration reaction is 3 - 5 h, and the dehydration reaction is carried out under reflux stirring conditions.

[0019] Preferably, the molar ratio of the compound containing an isocyan unit to Au(C6F5)(tht) in the step (4) is 1:(1.02 - 1.03).

[0020] The present invention provides the application of the luminescent material with aggregation-induced emission, thermochromic and photochromic properties described in the above technical solution or the luminescent material prepared by the preparation method described in the above technical solution in the fields of luminescent materials, temperature sensors, information storage devices and anti-counterfeiting.

[0021] The present invention provides a luminescent material with both aggregation-induced emission, thermochromism, and photochromism properties. The luminescent material provided by the present invention is a highly innovative monovalent gold complex containing a tricarbazole group. The monovalent gold atom can form aurophilic interactions, and carbazole has a special rigid planar structure, a large conjugated system, and good intramolecular electron transfer ability, enabling the luminescent material to simultaneously exhibit excellent properties such as aggregation-induced emission, thermochromism, and photofluorescence color change, and can be used as a temperature and ultraviolet light irradiation stimulus-responsive material. The luminescent material provided by the present invention shows almost no photoluminescence phenomenon in pure DMSO solvent, but once in the aggregated state, it will emit strong cyan-green light, and the aggregation-induced emission effect is extremely obvious; from the perspective of temperature response characteristics, the luminescent material shows blue at a low temperature of 77K and cyan-green at room temperature, showing completely different optical properties at different temperatures, and the thermochromic fluorescence color change effect is significant; at the same time, the solid powder of the luminescent material initially shows cyan-green luminescence, and when irradiated with 365nm ultraviolet light for 2min, the solid powder can change from cyan-green luminescence to blue luminescence, and the photochromic fluorescence color change effect is prominent. In summary, the luminescent material provided by the present invention has both aggregation-induced emission, thermochromism, and photochromism properties, making it have great application potential in the field of luminescent materials and can be used to develop high-performance luminescent devices; in the field of temperature sensors, it can accurately sense temperature changes by virtue of its thermochromic fluorescence color change effect; in the field of anti-counterfeiting, the unique photochromic and thermochromic fluorescence color change characteristics can provide reliable anti-counterfeiting means. The results of the examples show that the luminescent material provided by the present invention can exhibit excellent aggregation-induced emission properties, have different fluorescence properties at different temperatures, have thermochromic fluorescence color change properties, and after being irradiated with 365nm ultraviolet light for different times, the photoluminescence signal changes and undergoes a certain blue shift, indicating that the luminescent material has photochromism properties. Description of the Drawings

[0022] Figure 1 It is the photoluminescence spectrum of the luminescent material provided in Example 1 of the present invention in a mixed solvent of DMSO and water with different concentrations;

[0023] Figure 2 It is the photoluminescence spectrum of the luminescent material provided in Example 1 of the present invention at different temperatures;

[0024] Figure 3 It is the photoluminescence spectrum of the luminescent material provided in Example 1 of the present invention under different ultraviolet light irradiation times;

[0025] Figure 4 It is the photoluminescence physical diagram of the luminescent material provided in Example 1 of the present invention at the initial stage of ultraviolet light irradiation, after irradiation for 15s, and after irradiation for 2min. Detailed Embodiments

[0026] The present invention provides a luminescent material with both aggregation-induced emission, thermochromism and photochromism properties, and its structure is shown in Formula I:

[0027]

[0028] The luminescent material provided by the present invention is a highly innovative monovalent gold complex containing a tricarbazole group. The monovalent gold atom can form aurophilic interactions. Carbazole has a special rigid planar structure, a large conjugated system and good intramolecular electron transfer ability, so that the luminescent material simultaneously exhibits excellent properties such as aggregation-induced emission, thermochromism and photochromic fluorescence, and can be used as a temperature and ultraviolet light stimulation-responsive material. The luminescent material provided by the present invention shows almost no photoluminescence phenomenon in pure DMSO solvent, but once in the aggregated state, it will emit strong cyan-green light, and the aggregation-induced emission effect is extremely obvious; from the perspective of temperature response characteristics, the luminescent material shows blue at a low temperature of 77K, and cyan-green at room temperature, showing completely different optical properties at different temperatures, and the thermochromic fluorescence effect is significant; at the same time, the solid powder of the luminescent material initially shows cyan-green luminescence, and when irradiated with 365nm ultraviolet light for 2 minutes, the cyan-green luminescence can be converted into blue luminescence, and the photochromic fluorescence effect is prominent. In summary, the luminescent material provided by the present invention has both aggregation-induced emission, thermochromism and photochromism properties, making it have great application potential in the field of luminescent materials, and can be used to develop high-performance luminescent devices; in the field of temperature sensors, it can accurately sense temperature changes by virtue of its thermochromic fluorescence effect; in the field of anti-counterfeiting, the unique photochromic and thermochromic fluorescence properties can provide reliable anti-counterfeiting means.

[0029] The present invention also provides a preparation method of the luminescent material with both aggregation-induced emission, thermochromism and photochromism properties described in the above technical solution, including the following steps:

[0030] (1) Mix carbazole trimer, p-iodoacetanilide, cuprous oxide and N,N-dimethylacetamide, carry out Ullmann reaction, and then add dilute sulfuric acid for hydrolysis reaction to obtain an amino-containing compound;

[0031] (2) Mix the amino-containing compound obtained in step (1) with formic acid and carry out formylation reaction to obtain a compound containing a formamide unit;

[0032] (3) Mix the compound containing a formamide unit obtained in step (2), triphosgene, triethylamine and a first solvent, carry out dehydration reaction to obtain a compound containing an isocyan unit;

[0033] (4) Mix the compound containing isocyanide units obtained in the step (3), Au(C6F5)(tht), and a second solvent, and then carry out a coordination reaction to obtain a luminescent material with both aggregation-induced emission, thermochromic, and photochromic properties.

[0034] In the present invention, unless otherwise specified, the raw materials used are commercially available chemical products well-known to those skilled in the art.

[0035] In the present invention, there are no special requirements for the "first", "second", "third", and "fourth", and they are only used to distinguish solvents and post-treatment processes in different steps.

[0036] In the present invention, carbazole trimer, p-iodoacetanilide, cuprous oxide, and N,N-dimethylacetamide are mixed and then subjected to an Ullmann reaction, and then dilute sulfuric acid is added for hydrolysis reaction to obtain an amino-containing compound.

[0037] In the present invention, the molar ratio of the carbazole trimer, p-iodoacetanilide, and cuprous oxide is preferably 1:(1 - 1.1):(0.1 - 1); the volume ratio of the amount of substance of the carbazole trimer and N,N-dimethylacetamide is preferably (2 - 3) mmol:(30 - 100) mL, more preferably 2.5 mmol:(50 - 80) mL. By controlling the dosage relationship between the carbazole trimer and p-iodoacetanilide in the present invention, it is beneficial for them to react completely during the Ullmann reaction, reducing the waste of raw materials; cuprous oxide acts as a catalyst and can catalyze the reaction between the carbazole trimer and p-iodoacetanilide; N,N-dimethylacetamide acts as a solvent, which can provide an environment for the reaction and can also provide a protective environment for the subsequent hydrolysis reaction.

[0038] In the present invention, the preferred way to mix the carbazole trimer, p-iodoacetanilide, cuprous oxide, and N,N-dimethylacetamide is to first mix the carbazole trimer and p-iodoacetanilide, and then add cuprous oxide and N,N-dimethylacetamide.

[0039] In the present invention, the temperature of the Ullmann reaction is preferably 180 - 200 °C; the time of the Ullmann reaction is preferably 24 - 26 h; the Ullmann reaction is preferably carried out under reflux stirring conditions. By controlling the parameters of the Ullmann reaction in the present invention, the reaction efficiency can be further improved, ensuring complete reaction and reducing the waste of raw materials.

[0040] As an embodiment of the present invention, the temperature of the Ullmann reaction can be 180 °C, 185 °C, 190 °C, 195 °C, or 200 °C; the time of the Ullmann reaction can be 24 h, 24.5 h, 25 h, 25.5 h, or 26 h.

[0041] In the present invention, the volume ratio of the N,N-dimethylacetamide to the dilute sulfuric acid is preferably (30 to 100):(10 to 20); the concentration of the dilute sulfuric acid is preferably 0.1 to 4 mol / L, more preferably 0.5 to 2 mol / L. In the present invention, the temperature of the hydrolysis reaction is preferably room temperature; the time of the hydrolysis reaction is preferably 3 to 5 h. By adding dilute sulfuric acid, the present invention can catalyze the hydrolysis reaction of the amide group to generate an amino group, thereby obtaining an amino group-containing compound.

[0042] After the hydrolysis reaction is completed, the present invention preferably performs a first post-treatment on the product of the hydrolysis reaction to obtain an amino group-containing compound. In the present invention, the operation of the first post-treatment is preferably: first cooling the product of the hydrolysis reaction to room temperature, then extracting with dichloromethane, then washing the obtained organic layer with saturated brine, then combining the organic phases and drying, and finally performing solvent evaporation and column chromatography separation in sequence to obtain an amino group-containing compound. The present invention has no special limitation on the cooling rate, and natural cooling is sufficient. In the present invention, the number of extractions is preferably 2 to 5 times, preferably 3 to 4 times; the number of washings is preferably 2 to 5 times, preferably 3 to 4 times; the drying preferably uses anhydrous Na2SO4 for drying; the eluent used in the column chromatography separation is preferably a mixed solvent of petroleum ether and dichloromethane; the volume ratio of the petroleum ether to the dichloromethane is preferably 1:(1 to 6), more preferably 1:(2 to 5), and further preferably 1:(3 to 4). The present invention has no special limitation on the specific operations of the solvent evaporation and column chromatography separation, and the operations of the solvent evaporation and column chromatography separation well-known to those skilled in the art can be adopted. Through the first post-treatment, the present invention can remove impurities such as solvents and unreacted raw materials in the product, improve the purity of the amino group-containing compound, and facilitate the precise control of the raw material dosage in subsequent preparations.

[0043] After obtaining the amino group-containing compound, the present invention mixes the amino group-containing compound with formic acid and performs a formylation reaction to obtain a compound containing a formamide unit.

[0044] In the present invention, the molar ratio of the amino group-containing compound to formic acid is preferably 1:(200 to 700). By controlling the dosages of the two, on the one hand, formic acid can be used as a solvent, and on the other hand, a formyl group can be introduced into the amino group-containing compound to obtain a compound containing a formamide unit. As an embodiment of the present invention, the molar ratio of the amino group-containing compound to formic acid can be 1:200, 1:250, 1:300, 1:350, 1:400, 1:450, 1:500, 1:550, 1:600, 1:650 or 1:700.

[0045] In the present invention, the temperature of the formylation reaction is preferably 101 - 110 °C; the time of the formylation reaction is preferably 8 - 10 h; the formylation reaction is preferably carried out under reflux stirring conditions. By controlling the parameters of the formylation reaction, the present invention can further improve the reaction efficiency, ensure the completion of the reaction, increase the yield of the compound containing a formamide unit, and reduce the waste of raw materials.

[0046] As an embodiment of the present invention, the temperature of the formylation reaction can be 101 °C, 103 °C, 105 °C, 108 °C or 110 °C; the time of the formylation reaction can be 8 h, 8.5 h, 9 h, 9.5 h or 10 h.

[0047] After the formylation reaction is completed, the present invention preferably performs a second post-treatment on the product of the formylation reaction to obtain a compound containing a formamide unit. In the present invention, the operation of the second post-treatment is preferably as follows: first, perform atmospheric distillation on the product of the formylation reaction, then extract with dichloromethane, then wash the obtained organic layer with saturated brine, then combine the organic phases and dry, and finally spin out the solvent and perform column chromatography separation in sequence to obtain a compound containing a formamide unit. The present invention has no special limitation on the specific operation of the atmospheric distillation, and an atmospheric distillation operation well-known to those skilled in the art can be used as long as formic acid can be removed. In the present invention, the number of extractions is preferably 2 - 5 times, more preferably 3 - 4 times; the number of washings is preferably 2 - 5 times, more preferably 3 - 4 times; the drying preferably uses anhydrous Na2SO4 for drying; the eluent used in the column chromatography separation is preferably a mixed solvent of petroleum ether and ethyl acetate; the volume ratio of petroleum ether to ethyl acetate is preferably (1 - 3):1, more preferably 2:1. The present invention has no special limitation on the specific operations of spinning out the solvent and column chromatography separation, and the operations of spinning out the solvent and column chromatography separation well-known to those skilled in the art can be used. Through the second post-treatment, the present invention can remove impurities such as solvents and unreacted raw materials in the product, improve the purity of the compound containing a formamide unit, and facilitate the precise control of the raw material dosage in subsequent preparations.

[0048] After obtaining the compound containing a formamide unit, the present invention mixes the compound containing a formamide unit, triphosgene, triethylamine and a first solvent and performs a dehydration reaction to obtain a compound containing an isocyan unit.

[0049] In the present invention, the triphosgene is preferably subjected to air displacement treatment. The present invention has no special limitation on the specific operation of the air displacement treatment, and as long as the impurities in the triphosgene can be removed.

[0050] In the present invention, the molar ratio of the compound containing a formamide unit to triphosgene is preferably 1:(1.1 - 1.2). By controlling the dosages of the two, the present invention can ensure that the compound containing a formamide unit is reacted into a compound containing an isocyan unit as much as possible, improving the utilization rate of the product.

[0051] In the present invention, the mass ratio of the compound containing a formamide unit to the volume of triethylamine is preferably (1 - 2) g:(3 - 10) mL, more preferably (1.1 - 1.5) g:(4 - 6) mL, and further preferably (1.2 - 1.3) g:5 mL. By adding triethylamine, the present invention can adjust the alkalinity of the reaction system, and at the same time will not destroy the acidity and alkalinity of the organic reaction system, improving the reaction efficiency.

[0052] In the present invention, the first solvent is preferably dichloromethane or chloroform. In the present invention, the mass ratio of the compound containing a formamide unit to the volume of the first solvent is preferably (1 - 2) g:(30 - 80) mL, more preferably (1.1 - 1.5) g:(40 - 60) mL, and further preferably (1.2 - 1.3) g:50 mL. In the present invention, the first solvent is preferably subjected to dehydration drying and air evacuation treatment. The present invention has no special limitation on the specific operations of the dehydration drying and air evacuation treatment, and it is only necessary to remove the moisture and gas impurities in the first solvent. By the dehydration drying and air evacuation treatment, the present invention can remove the influence of moisture and gas impurities.

[0053] In the present invention, the mixing of the compound containing a formamide unit, triphosgene, triethylamine and the first solvent is preferably carried out in a three-necked flask. The present invention preferably pre-treats the three-necked flask before mixing; the pre-treatment preferably includes vacuum pumping and filling with N2; the number of times of vacuum pumping and filling with N2 is preferably 3 times. By the above process, the present invention can remove the gas in the three-necked flask and avoid the introduction of impurities.

[0054] In the present invention, the mixing method of the compound containing a formamide unit, triphosgene, triethylamine and the first solvent is preferably to mix the compound containing a formamide unit, triethylamine and a part of the first solvent to obtain a mixed solution of the compound containing a formamide unit and triethylamine, mix triphosgene and the remaining first solvent to obtain a triphosgene solution, and then drop the triphosgene solution into the mixed solution of the compound containing a formamide unit and triethylamine. In the present invention, the volume ratio of the part of the first solvent to the remaining first solvent is preferably 3:(1 - 3), more preferably 3:2. The present invention has no special limitation on the dropping rate, which can be determined according to the common technical knowledge of those skilled in the art. By mixing in the above manner, the present invention can make the mixing of each component more uniform.

[0055] In the present invention, the temperature of the dehydration reaction is preferably 50 - 60°C; the time of the dehydration reaction is preferably 3 - 5 h; the dehydration reaction is preferably carried out under reflux stirring conditions. By controlling the parameters of the dehydration reaction, the present invention can further improve the reaction efficiency, ensure complete reaction, increase the yield of the compound containing an isocyan unit, and reduce the waste of raw materials.

[0056] As an embodiment of the present invention, the temperature of the dehydration reaction can be 50°C, 53°C, 55°C, 58°C or 60°C; the time of the formylation reaction can be 3 h, 3.5 h, 4 h, 4.5 h or 5 h.

[0057] After the dehydration reaction is completed, the present invention preferably subjects the product of the dehydration reaction to a third post-treatment to obtain a compound containing an isocyan unit. In the present invention, the operation of the third post-treatment is preferably as follows: first, extract the product of the dehydration reaction with dichloromethane, then wash the obtained organic layer with saturated brine, then combine the organic phases and dry them, and finally carry out solvent evaporation and column chromatography separation in sequence to obtain a compound containing an isocyan unit. In the present invention, the number of extractions is preferably 2 - 5 times, more preferably 3 - 4 times; the number of washings is preferably 2 - 5 times, more preferably 3 - 4 times; the drying preferably uses anhydrous Na2SO4 for drying; the eluent used in the column chromatography separation is preferably a mixed solvent of petroleum ether and dichloromethane; the volume ratio of petroleum ether to dichloromethane is preferably 1:(1 - 6), more preferably 1:(2 - 5), and further preferably 1:(3 - 4). The present invention has no special limitation on the specific operations of solvent evaporation and column chromatography separation, and the operations of solvent evaporation and column chromatography separation well-known to those skilled in the art can be adopted. Through the third post-treatment, the present invention can remove impurities such as solvents and unreacted raw materials in the product, improve the purity of the compound containing an isocyan unit, and facilitate the precise control of the raw material dosage in subsequent preparations.

[0058] After obtaining the compound containing an isocyan unit, the present invention mixes the compound containing an isocyan unit, Au(C6F5)(tht), and a second solvent and carries out a coordination reaction to obtain a luminescent material with both aggregation-induced emission, thermochromic and photochromic properties.

[0059] In the present invention, tht in Au(C6F5)(tht) is preferably tetrahydrothiophene.

[0060] In the present invention, the molar ratio of the compound containing an isocyan unit to Au(C6F5)(tht) is preferably 1:(1.02 - 1.03). By controlling the dosage relationship between the two, the present invention can ensure complete reaction between the two, reduce the waste of raw materials, thereby further reducing the production cost and improving the market competitiveness of the luminescent material.

[0061] In the present invention, the second solvent is preferably dichloromethane or chloroform. In the present invention, the second solvent is preferably subjected to water removal drying and air evacuation treatment. The present invention has no special limitation on the specific operations of the water removal drying and air evacuation treatment, as long as the water and gas impurities in the second solvent can be removed. The present invention has no special limitation on the specific dosage of the second solvent, which is determined according to the common technical knowledge of those skilled in the art, as long as the compound containing an isocyanide unit and Au(C6F5)(tht) can be completely dissolved. As an embodiment of the present invention, the mass ratio of the compound containing an isocyanide unit to the volume of the second solvent can be (0.8 - 1.0) g : (20 - 40) mL. By controlling the type and dosage of the solvent, the present invention can provide a stable environment for the coordination reaction.

[0062] In the present invention, the temperature of the coordination reaction is preferably 20 - 30 °C; the time of the coordination reaction is preferably 10 - 12 h; the coordination reaction is preferably carried out under stirring conditions. By controlling the parameters of the coordination reaction, the present invention can further improve the reaction efficiency, ensure the completion of the reaction, increase the yield of the luminescent material, and reduce the waste of raw materials.

[0063] As an embodiment of the present invention, the temperature of the coordination reaction can be 20 °C, 23 °C, 25 °C, 28 °C or 30 °C; the time of the coordination reaction can be 10 h, 10.5 h, 11 h, 11.5 h or 12 h. The present invention has no special limitation on the stirring rate, which is determined according to the common technical knowledge of those skilled in the art, as long as splashing of the solution is avoided.

[0064] After the coordination reaction is completed, the present invention preferably performs a fourth post-treatment on the product of the coordination reaction to obtain a luminescent material with both aggregation-induced emission, thermochromic and photochromic properties. In the present invention, the operation of the fourth post-treatment is preferably as follows: first, the second solvent in the product of the coordination reaction is rotary-evaporated to obtain a solid product, then the second solvent is added to just dissolve the solid product, then n-hexane is added, and finally suction filtration is carried out to obtain a luminescent material with both aggregation-induced emission, thermochromic and photochromic properties. The present invention has no special limitation on the specific operation of the rotary evaporation, and the operation of rotary-evaporating the solvent well-known to those skilled in the art can be adopted. The present invention has no special limitation on the specific dosage of the n-hexane, which is determined according to the common technical knowledge of those skilled in the art. Through the fourth post-treatment, the present invention can remove impurities such as solvents and unreacted raw materials in the product, thereby improving the purity of the luminescent material.

[0065] The synthetic route diagram of the luminescent material provided by the present invention is preferably as shown in Formula II:

[0066]

[0067] In Formula II, 1-1 is a carbazole trimer, 1-2 is an amino group-containing compound, 1-3 is a compound containing a formamide unit, 1-4 is a compound containing an isocyan unit, and 1 is a luminescent material with both aggregation-induced emission, thermochromic and photochromic properties.

[0068] It can be seen from the preparation method of the present invention in combination with Formula II that the present invention uses a carbazole trimer as a raw material. First, through the Ullmann reaction and hydrolysis reaction, an amino group-containing compound is obtained. Then, through a formylation reaction, a compound containing a formamide unit is obtained. Next, a dehydration reaction is carried out to obtain a compound containing an isocyan unit. Finally, a coordination reaction is carried out to obtain a luminescent material with both aggregation-induced emission, thermochromic and photochromic properties.

[0069] The preparation method provided by the present invention is simple. There is no need for high temperature, high pressure and other environments during the preparation process. The reaction conditions are mild. The dosage of raw materials is accurately controlled, with less waste and low cost, and it is suitable for large-scale industrial promotion.

[0070] The present invention also provides the application of the luminescent material with both aggregation-induced emission, thermochromic and photochromic properties described in the above technical solution or the luminescent material with both aggregation-induced emission, thermochromic and photochromic properties prepared by the preparation method described in the above technical solution in the fields of luminescent materials, temperature sensors, information storage devices and anti-counterfeiting.

[0071] The present invention has no special limitation on the specific manner of the application, and the application can be carried out in a manner well-known to those skilled in the art.

[0072] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts belong to the scope of protection of the present invention.

[0073] Example 1

[0074] A luminescent material with both aggregation-induced emission, thermochromic and photochromic properties, whose structure is shown in Formula I:

[0075]

[0076] The preparation method of the luminescent material with both aggregation-induced emission, thermochromic and photochromic properties is as follows:

[0077] (1) 1.24 g (2.50 mmol) of carbazole trimer and 0.69 g (2.61 mmol) of p-iodoacetanilide were added into a 100 mL three-necked flask. The molar ratio of carbazole trimer to p-iodoacetanilide was 1:1.044. Then, copper(I) oxide and 100 mL of N,N-dimethylacetamide were added. The molar ratio of carbazole trimer to copper(I) oxide was 1:0.1. The Ullmann reaction was carried out under reflux stirring conditions. Then, 10 mL of 0.5 mol / L dilute sulfuric acid was added for hydrolysis reaction for 3 h. Finally, the first post-treatment was carried out to obtain an amino group-containing compound. The temperature of the Ullmann reaction was 200 °C, and the time of the Ullmann reaction was 24 h. The operation of the first post-treatment was as follows: first, it was naturally cooled to room temperature, then extracted with dichloromethane 3 times. Next, the obtained organic layer was washed with saturated brine 3 times. Then, the organic phases were combined and dried with anhydrous Na2SO4. Finally, the solvent was evaporated and column chromatography separation was carried out (the eluent was a mixed solvent of petroleum ether and dichloromethane with a volume ratio of 1:6) to obtain an amino group-containing compound;

[0078] (2) 1.25 g (2.13 mmol) of the amino group-containing compound obtained in the step (1) was added into a 100 mL three-necked flask. Then, 50 mL of formic acid was added. Next, the formylation reaction was carried out under reflux stirring conditions. Finally, the second post-treatment was carried out to obtain a compound containing a formamide unit. The temperature of the formylation reaction was 110 °C, and the time of the formylation reaction was 8 h. The operation of the second post-treatment was as follows: first, formic acid was removed by atmospheric distillation. Then, it was extracted with dichloromethane 3 times. Next, the obtained organic layer was washed with saturated brine 3 times. Then, the organic phases were combined and dried with anhydrous Na2SO4. Finally, the dichloromethane solvent was evaporated and column chromatography separation was carried out (the eluent was a mixed solvent of petroleum ether and ethyl acetate with a volume ratio of 2:1) to obtain a compound containing a formamide unit;

[0079] (3) After evacuating and filling N2 into a 100 mL three-necked flask three times, 1.23 g (1.99 mmol) of the compound containing a formamide unit obtained in the above step (2), 5 mL of triethylamine and 30 mL of dichloromethane were added. Then, 20 mL of a dichloromethane solution of triphosgene was added dropwise, and a dehydration reaction was carried out under reflux stirring conditions. Finally, a third post-treatment was carried out to obtain a compound containing an isocyan unit; the dichloromethane solution of triphosgene was prepared by mixing 0.69 g (2.34 mmol) of triphosgene and 20 mL of dichloromethane, and the triphosgene was subjected to air displacement treatment; the dichloromethane was subjected to water removal, drying and air displacement treatment; the temperature of the dehydration reaction was 60 °C, and the time of the dehydration reaction was 3 h; the operation of the third post-treatment was as follows: first, the product of the dehydration reaction was extracted 3 times with dichloromethane, then the extracted organic layer was washed 3 times with saturated brine, then the organic phases were combined and dried with anhydrous Na2SO4 for 3 h, and finally, the dichloromethane solvent was evaporated and column chromatography separation (the eluent was a mixed solvent of petroleum ether and dichloromethane with a volume ratio of 6:1) was carried out in sequence to obtain a compound containing an isocyan unit;

[0080] (4) After evacuating and filling N2 into a 100 mL three-necked flask three times, 0.90 g (1.50 mmol) of the compound containing an isocyan unit obtained in the above step (3), 0.69 g (1.53 mmol) of Au(C6F5)(tht) (tht is tetrahydrothiophene) and 30 mL of dichloromethane were added. A coordination reaction was carried out under stirring conditions. Finally, a fourth post-treatment was carried out to obtain a luminescent material with aggregation-induced emission, thermochromic and photochromic properties; the second solvent was subjected to water removal, drying and air displacement treatment; the temperature of the coordination reaction was 25 °C, and the time of the coordination reaction was 10 h; the operation of the fourth post-treatment was as follows: first, the dichloromethane in the product of the coordination reaction was evaporated to obtain a solid product, then dichloromethane was added to dissolve the solid product, then n-hexane was added, and finally filtration was carried out.

[0081] The aggregation-induced emission effect of the luminescent material prepared in Example 1 was tested. The test method was as follows: 10 equal amounts of the luminescent material were respectively placed into a mixed solvent of DMSO and water. In the mixed solvent, the volume fractions of water were 0, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% and 90% in sequence. In the mixed solvent, the concentration of the luminescent material was 1×10 -5 mol / L. Then, a photoluminescence spectrum was obtained at an excitation wavelength of 365 nm, and the results are as Figure 1 shown. It can be seen from Figure 1 that as the degree of aggregation increases continuously (i.e., the volume fraction of water in the solvent increases), the photoluminescence signal of the luminescent material provided by the present invention is significantly enhanced, indicating that the luminescent material can exhibit excellent aggregation-induced emission properties.

[0082] The thermochromic properties of the luminescent material prepared in Example 1 were tested. The test method was as follows: The luminescent material was placed at room temperature, then observed under 365 nm ultraviolet light irradiation. Next, it was placed at a temperature of 77 K, and then observed again under 365 nm ultraviolet light irradiation. The obtained photoluminescence spectra are as Figure 2 shown. It can be seen from Figure 2 that at different temperatures, the luminescent material provided by the present invention has different fluorescence properties and exhibits thermally induced fluorescence color change properties.

[0083] The photochromic properties of the luminescent material prepared in Example 1 were tested. The test method was as follows: The luminescent material was irradiated with 365 nm ultraviolet light initially, for 5 s, 15 s, 30 s, 1 min, and 2 min. The obtained photoluminescence spectra are as Figure 3 shown, and the actual photoluminescence pictures under 365 nm ultraviolet light irradiation initially, for 15 s, and for 2 min are as Figure 4 shown. From Figure 3 and Figure 4 it can be seen that after the luminescent material provided by the present invention is irradiated with 365 nm ultraviolet light, the photoluminescence signal changes and exhibits a certain blue shift, indicating that the luminescent material has photochromic properties.

[0084] In summary, the luminescent material provided by the present invention is a very rare monovalent gold complex containing a tricarbazole group that simultaneously exhibits aggregation-induced emission, thermally induced and photochemically induced fluorescence color change properties, and is expected to find applications in the fields of luminescent materials, temperature sensors, anti-counterfeiting, etc.

[0085] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A luminescent material with aggregation-induced emission, thermochromic and photochromic properties, and its structure is shown in Formula I:

2. A preparation method of the luminescent material with aggregation-induced emission, thermochromic and photochromic properties as described in Claim 1, comprising the following steps: (1) Mix carbazole trimer, p-iodoacetanilide, cuprous oxide and N,N-dimethylacetamide, carry out Ullmann reaction, and then add dilute sulfuric acid for hydrolysis reaction to obtain an amino-containing compound; (2) Mix the amino-containing compound obtained in step (1) and formic acid, and carry out formylation reaction to obtain a compound containing a formamide unit; (3) Mix the compound containing a formamide unit obtained in step (2), triphosgene, triethylamine and a first solvent, and carry out dehydration reaction to obtain a compound containing an isocyan unit; (4) Mix the compound containing an isocyan unit obtained in step (3), Au(C6F5)(tht) and a second solvent, and carry out coordination reaction to obtain a luminescent material with aggregation-induced emission, thermochromic and photochromic properties.

3. The preparation method according to claim 2, wherein In step (1), the molar ratio of carbazole trimer to p-iodoacetanilide is 1:(1-1.1).

4. The preparation method according to claim 2, characterized in that, In step (1), the temperature of the Ullmann reaction is 180-200 °C, the time of the Ullmann reaction is 24-26 h, and the Ullmann reaction is carried out under reflux stirring conditions.

5. The preparation method according to claim 2, characterized in that, In step (2), the molar ratio of the amino-containing compound to formic acid is preferably 1:(200-300).

6. The preparation method according to claim 2, characterized in that, In step (2), the temperature of the formylation reaction is 101-110 °C, the time of the formylation reaction is 8-10 h, and the formylation reaction is carried out under reflux stirring conditions.

7. The preparation method according to claim 2, characterized in that, In step (3), the molar ratio of the compound containing a formamide unit to triphosgene is 1:(1.1-1.2).

8. The preparation method according to claim 2, wherein In step (3), the temperature of the dehydration reaction is 50-60 °C, the time of the dehydration reaction is 3-5 h, and the dehydration reaction is carried out under reflux stirring conditions.

9. The preparation method according to claim 2, wherein In step (4), the molar ratio of the compound containing an isocyan unit to Au(C6F5)(tht) is 1:(1.02-1.03).

10. The application of the luminescent material with aggregation-induced emission, thermochromic and photochromic properties as described in Claim 1 or the luminescent material with aggregation-induced emission, thermochromic and photochromic properties prepared by the preparation method described in any one of Claims 2-9 in the fields of luminescent materials, temperature sensors, information storage devices and anti-counterfeiting.

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