Thermoluminescence color-changing metal nanomaterial, preparation method and application thereof

Abstract

The application discloses a metal nanomaterial, in particular discloses a thermoluminescence color-changing metal nanomaterial, a preparation method and application thereof. The thermoluminescence color-changing metal nanomaterial exhibits a significant temperature-dependent characteristic in emission intensity under ultraviolet excitation. The thermoluminescence color-changing metal nanomaterial can be used as a nanometer fluorescence thermometer and has wide application in the technical fields of biological medicine, environmental monitoring and nanoelectronics.

Description

Technical Field

[0001] The invention relates to a thermoluminescent color-changing metal nano material, a preparation method and an application thereof, and belongs to the technical field of metal nano materials. Background Art

[0002] With the continuous advancement of technology, temperature monitoring has become increasingly important in many fields, such as industrial process control, environmental monitoring, medical diagnosis, and bioimaging. However, traditional thermometers often suffer from drawbacks such as large size, invasive temperature measurement, and slow response speed, which limit their effectiveness in many applications. Therefore, the development of new temperature sensing materials is of great practical significance.

[0003] In recent years, fluorescence thermometry has garnered widespread attention due to its remote temperature measurement, non-invasive nature, high sensitivity, and high spatial resolution. This technology leverages the temperature-dependent emission intensity of fluorescent materials to achieve non-contact temperature measurement. Compared to traditional temperature measurement methods, fluorescence thermometers offer faster response times and higher measurement accuracy, making them particularly suitable for applications sensitive to temperature fluctuations. Among the many temperature-sensitive fluorescent materials, silver cluster nanomaterials, a class of metal nanomaterials, exhibit promising application potential in biomedicine, bioprocess monitoring, and biotechnology due to their excellent optical properties, low toxicity, and good biocompatibility. Although some silver nanocluster materials with temperature-dependent fluorescence intensity have been synthesized and reported, their overall number remains limited. Further exploration and development of new silver cluster nanomaterials will not only enrich the material library of fluorescence thermometers but also promote research and application development in related fields. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a novel thermoluminescent color-changing metal nanomaterial; during the temperature change process, the emission intensity at 606nm and 492nm shows good linear and exponential relationships, respectively, and it can be applied to technical fields such as biomedicine, environmental monitoring and nanoelectronics.

[0005] The first object of the present invention is to provide a thermoluminescent color-changing metal nanomaterial, the molecular formula of which is [Ag 36 (Hdecz) 12 (CF3SO3)4(NO3)3(dppm)4](CF3SO3)5;

[0006] The NO3 is a nitrate; the CF3SO3 is a trifluoromethanesulfonate;

[0007] The dppm is bis(diphenylphosphino)methane The Hdecz is

[0008] According to the present application, preferably, the thermally induced luminescent color-changing metal nanomaterials described above can be prepared by the following method.

[0009] (1) Silver acetylide precursor: under alkaline conditions, silver (I) salt and 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole are polymerized in a solvent to generate a silver acetylide precursor;

[0010] (2) The silver acetylide precursor, silver (I) triflate and bis (diphenylphosphine) methane and nitrate salt are dissolved in a solvent to prepare by self-assembly reaction;

[0011] The structural formula of 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole is

[0012] According to the present application, preferably, in step (1), the silver (I) salt can be one or more combinations of Ag2O, AgNO3, AgF, AgCl, AgBr, AgI, CF3SO3Ag, AgClO4, AgBF4, AgPF6 or AgSbF6.

[0013] According to the present application, preferably, in step (1), depending on the different silver (I) salts, the polar solvent can be one or more combinations of water, chloroform, dichloromethane, acetonitrile, ethanol or methanol.

[0014] According to the present application, preferably, in step (1), the base can be one or more combinations of ammonia, triethylamine, sodium hydroxide, potassium hydroxide, sodium hydride, calcium hydride, sodium methoxide, tetramethyl ethylenediamine, tetramethyl ammonium hydroxide, tetrabutyl ammonium hydroxide, tetrapropyl ammonium hydroxide, tetraethyl ammonium hydroxide.

[0015] According to the present application, preferably, in step (1), the molar ratio of silver (I) salt to 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole is 2-2.5:1.

[0016] According to the present application, preferably, in step (2), the polar solvent can be one or more combinations of dichloromethane, chloroform, acetonitrile, 1,2-dichloroethane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide.

[0017] According to the present application, preferably, in step (2), the nitrate salt is one or more combinations of potassium nitrate, sodium nitrate, ammonium nitrate, tetramethyl ammonium nitrate, tetraethyl ammonium nitrate, tetrapropyl ammonium nitrate, tetrabutyl ammonium nitrate.

[0018] According to the application, preferably, in step (2), the reaction ratio of the silver acetylide precursor, silver (I) trifluoromethanesulfonate, bis(diphenylphosphino)methane and nitrate is 11-13:11-13:3-5:2-4, and the optimal reaction molar ratio is 12:12:4:3.

[0019] The second object of the application is to provide a preparation method of the thermoluminescence color-changing metal nanomaterial.

[0020] The third object of the application is to provide a crystal form of the thermoluminescence color-changing metal nanomaterial. α (deg) = 90; β (deg) = 102.191 (3); γ (deg) = 90.

[0021] The fourth object of the application is to provide an application of the thermoluminescence color-changing metal nanomaterial in a molecular fluorescence thermometer.

[0022] At room temperature, the thermoluminescence color-changing metal nanomaterial presents orange-red emission when excited by ultraviolet light (λ ex = 250-500 nm). The maximum emission peak is 600 nm, and the maximum emission peak lifetime is 59.8 ns. When the temperature decreases from 30℃ to -190℃, the maximum emission peak at 600 nm gradually red shifts to 606 nm. The emission intensity at 606 nm presents a linear growth relationship with the temperature. In addition, when the temperature decreases, a new emission peak appears at 492 nm, and the emission intensity presents an exponential growth relationship with the temperature.

[0023] Therefore, the above-mentioned silver metal nanomaterial can be used as a core material of a nanofluorescence thermometer.

[0024] On the basis of not violating the common sense in the art, the above-mentioned preferred conditions can be combined arbitrarily, that is, the preferred embodiments of the application are obtained.

[0025] The reagents and raw materials used in the application are commercially available, except for special instructions.

[0026] The technical features and beneficial effects of the application are as follows:

[0027] The 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole ligand used in the thermoluminescence color-changing metal nanomaterial has multiple deprotonation modes, and each ethynyl group also exhibits rich coordination modes, which makes the nanocluster be able to assemble silver nanoclusters with diverse topological structures and rich luminescence characteristics.

[0028] The preparation method disclosed in the application is simple and mild, and the post-treatment process is relatively simple, which meets the needs of industrial production.

[0029] The nanoclusters exhibit significant temperature-dependent emission characteristics over a wide temperature range, specifically from 30°C to -190°C. At 606nm and 492nm, the emission intensity shows good linear and exponential relationships with temperature, respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A single crystal structure of a thermoluminescent color-changing metal nanomaterial. For simplicity, all hydrogen atoms, the tert-butyl group on 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole, and the benzene ring on bis(diphenylphosphino)methane are omitted.

[0031] Figure 2 The excitation of thermoluminescent color-changing metal nanomaterials in the solid state (λ em = 600 nm, dotted line) and emission (λ ex =365nm, solid line) curve.

[0032] Figure 3 is the maximum emission peak of thermoluminescent color-changing metal nanomaterials in the solid state (λ max =600nm) life decay curve.

[0033] Figure 4 This is the temperature-dependent fluorescence curve of the thermoluminescent color-changing metal nanomaterial in the solid state, with an excitation wavelength of 365nm.

[0034] Figure 5 The graph shows the variation of the emission intensity of the solid-state thermoluminescent color-changing metal nanomaterial at λ=606nm with temperature.

[0035] Figure 6 The graph shows the variation of emission intensity of solid-state thermoluminescent color-changing metal nanomaterials at λ=492nm with temperature. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and technical effect of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and examples; however, the present invention is not limited to the embodiments described. Experimental methods in the following examples without specifying specific conditions may be selected according to conventional methods and conditions, or according to product specifications.

[0037] The 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole involved in the present invention was prepared according to Dalton Trans. 2017, 46, 4696-4710, and other reagents and solvents were commercially available.

[0038] Example 1: Synthesis method of thermoluminescent color-changing metal nanomaterials in the present invention

[0039] (1) 1 equivalent of silver oxide was weighed and added to 25% ammonia water, stirred until clear, to obtain a silver ammonia solution. 1 equivalent of 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole was dissolved in 1,4-dioxane, and was added dropwise to the silver ammonia solution under vigorous stirring, and a red precipitate was rapidly formed. Stirring was continued for 6 hours. Then, filtration was performed, and washing was performed with water 3 times, and the water was removed under vacuum to obtain a red silver alkyne precursor, with a yield of 82.7%.

[0040] (2) 12 equivalents of silver alkyne precursor, 12 equivalents of silver (I) triflate, 4 equivalents of bis(diphenylphosphino)methane, and 3 equivalents of ammonium nitrate were dissolved in dichloromethane, and stirring was performed at room temperature for 12 hours to obtain a deep red solution. The mother liquor was transferred to a test tube, and 3 times the volume of n-hexane was spread on the interface for interfacial diffusion, and the test tube was sealed and left to stand for 5 days to obtain red block-shaped thermoluminescence color-changing metal nanomaterial crystals, with a crystal yield of 80.5%.

[0041] Example 2: Synthesis method of the thermoluminescence color-changing metal nanomaterial in the application

[0042] (1) 2 equivalents of silver nitrate were weighed and dissolved in water, and were added dropwise to 25% ammonia water. A gray precipitate was first formed in the system, and then the precipitate slowly dissolved, and the dropwise addition was stopped when the system was clear again to obtain a silver ammonia solution. 1 equivalent of 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole was dissolved in 1,4-dioxane, and was added dropwise to the silver ammonia solution under vigorous stirring, and a red precipitate was rapidly formed. Stirring was continued for 6 hours. Then, filtration was performed, and washing was performed with water 3 times, and the water was removed under vacuum to obtain a red silver alkyne precursor, with a yield of 83.5%.

[0043] (2) 12 equivalents of silver alkyne precursor, 12 equivalents of silver (I) triflate, 4 equivalents of bis(diphenylphosphino)methane, and 3 equivalents of tetrabutylammonium nitrate were dissolved in chloroform, and stirring was performed at room temperature for 12 hours to obtain a deep red solution. The reaction mother liquor was left to stand in the dark and volatilize for one week to obtain red flaky thermoluminescence color-changing metal nanomaterial crystals, with a crystal yield of 82.5%.

[0044] Example 3: Synthesis method of the thermoluminescence color-changing metal nanomaterial in the application

[0045] (1) 2 equivalents of silver nitrate were weighed and added to a methanol solution in which 1 equivalent of 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole was dissolved. 10 equivalents of triethylamine were added dropwise under vigorous stirring, and a large amount of red precipitate was rapidly formed. Stirring was continued for 6 hours until the white silver nitrate crystals completely disappeared. Then, filtration was performed, and washing was performed with methanol 3 times, and the methanol was removed under vacuum to obtain a red silver alkyne precursor, with a yield of 70.6%.

[0046] (2) 12 equivalents of silver acetylide precursor, 12 equivalents of silver (I) triflate, 4 equivalents of bis(diphenylphosphino)methane and 3 equivalents of potassium nitrate were dissolved in N,N-dimethylacetamide, stirred at room temperature for 12 h to obtain a deep red solution. The mother liquor was transferred to a test tube, and 3 times the volume of diethyl ether was spread on the interface for interfacial diffusion, and sealed for 7 days. Red block thermoluminescence color-changing metal nanomaterial crystals were obtained, with a crystal yield of 40.5%.

[0047] Example 4: Synthesis method of thermoluminescence color-changing metal nanomaterials in the present application

[0048] (1) 2 equivalents of silver (I) triflate (0.2 mmol) and 1 equivalent of 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole were weighed and dichloromethane was added, and all the reactants were ultrasonically dissolved. 10 equivalents of triethylamine were added dropwise to the system, and the reaction solution changed from light yellow to deep red, and stirring was continued for 6 hours. All the dichloromethane and excess triethylamine were removed. Washing with methanol 3 times, filtering, and vacuum drying of methanol to obtain a red silver acetylide precursor with a yield of 77.8%.

[0049] (2) 12 equivalents of silver acetylide precursor, 12 equivalents of silver (I) triflate, 4 equivalents of bis(diphenylphosphino)methane and 3 equivalents of potassium nitrate were dissolved in dichloromethane, stirred at room temperature for 12 h to obtain a deep red solution. The mother liquor was transferred to a test tube, and 3 times the volume of n-hexane was spread on the interface for interfacial diffusion, and sealed for 5 days. Red block thermoluminescence color-changing metal nanomaterial crystals were obtained, with a crystal yield of 35.8%.

[0050] Example 5: Synthesis method of thermoluminescence color-changing metal nanomaterials in the present application

[0051] (1) 1 equivalent of 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole and 2 equivalents of sodium hydroxide were weighed and methanol was added, and ultrasonic was applied until the sodium hydroxide was completely dissolved. Then 2 equivalents of AgBF4 were added, and a large amount of red precipitate was quickly generated, and stirring was continued for 6 h. Filtration, washing with methanol 3 times, and vacuum drying of methanol to obtain a red silver acetylide precursor with a yield of 80.1%.

[0052] (2) 12 equivalents of silver acetylide precursor, 12 equivalents of silver (I) triflate, 4 equivalents of bis(diphenylphosphino)methane and 3 equivalents of potassium nitrate were dissolved in dichloromethane, stirred at room temperature for 12 h to obtain a deep red solution. The mother liquor was transferred to a test tube, and 3 times the volume of n-hexane was spread on the interface for interfacial diffusion, and sealed for 5 days. Red block thermoluminescence color-changing metal nanomaterial crystals were obtained, with a crystal yield of 35.8%.

[0053] Example 6: Structural characterization

[0054] Single crystal structure characterization was performed using the crystal obtained in Example 1 as an example. The X-ray single crystal diffraction data of the crystal was collected on a Bruker Diffractometer MD2 diffractometer at the National Center for Protein Science (NCPSS) BL17B line station in Shanghai. The data processing used the Bruker APEX4 program. The wavelength of the light source was 0.7107 A. The test temperature was 273 K. The crystal was a triclinic Cc space group. The unit cell volume was 46077 (8). Ag 26 The molecular formula of the cluster was C 397 H 364 Ag 36 F 27 N 15 O 36 P8S9. Its molecular weight was 10853.89. Other crystal-related information is shown in Table 1:

[0055] Table 1

[0056]

[0057] Ag 36 The single crystal structure of the silver nanocluster is shown in Figure 1 , and its molecular formula is [Ag 36 (Hdecz) 12 (CF3SO3)4(NO3)3(dpp

[0058] m)4](CF3SO3)5. The core of the silver cluster is composed of thirty-six silver atoms, and the shell is composed of twelve deprotonated 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole, four trifluoromethanesulfonates, three nitrates, and four bis(diphenylphosphino)methane, and the counterion is trifluoromethanesulfonate. In the coordination process, 3,6-di-tert-butyl-1,8-diethyl-9H-carbazole coordinates with silver atoms by removing hydrogen from the double-ethynyl group, forming various coordination modes, including: (1) μ3-η 1 :η 1 :η 1 ,μ3-η 1 :η 1 :η 1 (2) μ3-η 2 :η 1 :η 1 , μ3-η 1 :η 1 :η 1 (3) μ3-η 2 :η 1 :η 1 , μ3-η 2 :η2 :η 1 (4) μ4-η2:η1:η1:η1, μ4-η2:η1:η1:η1 (5) μ4-η1:η1:η1:η1, μ4-η2:η1:η1:η1 The nitrate ion is divided into two groups, of which two are coordinated to one silver atom through Ag-O bonds The other adopts a bidentate coordination mode to bridge three silver atoms One oxygen atom of the triflate is coordinated to one silver atom through Ag-O bond. Bis(diphenylphosphino)methane as bidentate ligand, then bridges two silver atoms through Ag-P bonds.

[0059] Example 7: Photophysical test

[0060] In the present application, the thermoluminescence color change properties of the material are studied in depth. In the present application, the excitation and emission spectra and the emission lifetime are characterized by Edinburgh Instruments (FLS920 fluorescence spectrometer). At room temperature, when the metal nanomaterial is excited by ultraviolet light with a wavelength of 250-500 nm, it exhibits orange-red fluorescent emission, with a maximum emission peak at 600 nm( Figure 2 ), and a fluorescence lifetime of 59.8 ns( Figure 3 ). As the temperature decreases from 30℃ to -190℃, the emission peak at 600 nm gradually red shifts to 606 nm( Figure 4 ). At the same time, the emission intensity at 606 nm shows a linear relationship with temperature( Figure 5 ). In addition, as the temperature decreases, a new emission peak appears at 492 nm, and the emission intensity shows an exponential growth relationship with temperature( Figure 6 ).

Claims

1. A thermoluminescent color-changing metal nanomaterial, the molecular formula of which is [Ag 36 (Hdecz) 12 (CF3SO3)4(NO3)3(dppm)4](CF3SO3)5; The NO3 is a nitrate; the CF3SO3 is a trifluoromethanesulfonate; The dppm is bis(diphenylphosphino)methane The Hdecz is 2. The method for preparing the thermoluminescent color-changing metal nanomaterial according to claim 1, characterized in that: The thermoluminescent color-changing metal nanomaterial is prepared by the following method: (1) Under alkaline conditions, a silver (I) compound and 3,6-di-tert-butyl-1,8-diethynyl-9H-carbazole undergo polymerization reaction in a solvent to generate an acetylene silver precursor; the silver (I) compound is one or a combination of more than one of Ag2O, AgNO3, AgF, AgCl, AgBr, AgI, CF3SO3Ag, AgClO4, AgBF4, AgPF6 or AgSbF6. (2) dissolving the silver acetylene precursor, silver (I) trifluoromethanesulfonate, bis(diphenylphosphine)methane and nitrate in a solvent, and preparing the thermoluminescent color-changing metal nanomaterial through a self-assembly reaction; Wherein, the structural formula of the 3,6-di-tert-butyl-1,8-diethynyl-9H-carbazole is 3. The method for preparing the thermoluminescent color-changing metal nanomaterial according to claim 2, characterized in that: In step (1), the silver (I) compound is one or a combination of more than one of CF3SO3Ag, AgClO4, AgBF4, AgPF6 or AgSbF6.

4. The method for preparing the thermoluminescent color-changing metal nanomaterial according to claim 2, characterized in that: In step (1), the solvent is one or a combination of more than one of water, chloroform, dichloromethane, acetonitrile, ethanol or methanol.

5. The method for preparing the thermoluminescent color-changing metal nanomaterial according to claim 2, characterized in that: In step (1), the base is one or a combination of more than one of ammonia water, triethylamine, sodium hydroxide, potassium hydroxide, sodium hydride, calcium hydride, sodium methoxide, tetramethylethylenediamine, tetramethylammonium hydroxide, tetrabutylammonium hydroxide, tetrapropylammonium hydroxide, and tetraethylammonium hydroxide.

6. The method for preparing the thermoluminescent color-changing metal nanomaterial according to claim 2, characterized in that: In step (1), the molar ratio of the silver (I) compound to 3,6-di-tert-butyl-1,8-diethynyl-9H-carbazole is 2-2.5:

1.

7. The method for preparing silver metal nanomaterials according to claim 2, wherein: In step (2), the nitrate is one or a combination of more than one of potassium nitrate, sodium nitrate, ammonium nitrate, tetramethylammonium nitrate, tetraethylammonium nitrate, tetrapropylammonium nitrate, and tetrabutylammonium nitrate.

8. The method for preparing the thermoluminescent color-changing metal nanomaterial according to claim 2, characterized in that: In step (2), the solvent is one or a combination of dichloromethane, chloroform, acetonitrile, 1,2-dichloroethane, dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide; And / or, in step (2), the reaction ratio of the acetylenic silver precursor, silver (I) trifluoromethanesulfonate, bis(diphenylphosphino)methane and nitrate is 11-13:11-13:3-5:2-4.

9. A crystal form of the thermoluminescent color-changing metal nanomaterial according to claim 1, characterized in that: Unit cell parameters of the crystal form: α(deg)=90; β(deg)=102.191(3); γ(deg)=90.

10. Use of the thermoluminescent color-changing metal nanomaterial according to claim 1 in a ratiometric fluorescence thermometer.

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