Preparation method and application of a water-phase artificial light harvesting system of carbazole
An aqueous artificial light-harvesting system formed by the self-assembly of carbazole compounds and columnar aromatic compounds solves the problem of low energy transfer efficiency in aqueous solutions, achieves high-efficiency energy transfer and tunable fluorescence color, and provides a stable light-harvesting material.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NANTONG UNIV
- Filing Date
- 2023-06-25
- Publication Date
- 2026-04-21
AI Technical Summary
Existing artificial light-harvesting systems have low energy transfer efficiency in aqueous solutions, and traditional donor chromophores have aggregation-induced quenching effects, making it difficult to construct efficient aqueous light-harvesting systems.
Carbazole compound G and phosphate-modified columnar aromatic compound H are used to form supramolecular nanoparticles through host-guest interactions. These nanoparticles are then combined with fluorescent dyes to form an aqueous artificial light-harvesting system. Compound G acts as the energy donor, compound H acts as the host molecule, and the fluorescent dye acts as the energy acceptor.
A highly efficient light-harvesting system was constructed in the aqueous phase, with an energy transfer efficiency of up to 75%, an antenna effect of 40%, and tunable fluorescence color, providing a low-cost and environmentally friendly light-harvesting material.
Smart Images
Figure CN116925745B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of luminescent materials technology for supramolecular artificial light-harvesting systems, specifically relating to a preparation method and application of a carbazole-based aqueous artificial light-harvesting system. Background Technology
[0002] Photosynthesis is fundamental to the survival of living organisms. In the initial stage of photosynthesis, sunlight is captured, transferred, and ultimately converted into chemical energy. This process mainly occurs in chloroplasts, where pigment molecules can bind to proteins non-covalently to form protein complexes, capturing solar energy. These pigment molecules are called antenna pigment molecules. After capturing solar energy, the pigment molecules can transfer it to the reaction center through continuous energy transfer, catalyzing chemical reactions and ultimately converting solar energy into chemical energy. The dense cluster of antenna pigment molecules surrounding the reaction center is the most prominent feature of natural light-capturing systems, enabling green plants to complete photosynthesis even under extremely low light conditions. Inspired by nature, researchers have made significant progress in constructing artificial light-capturing systems based on the fluorescence resonance energy transfer (FRET) process to simulate the natural light-capturing process by achieving efficient energy transfer from donor to acceptor.
[0003] In particular, supramolecular self-assembly provides a simple and efficient method for constructing artificial light-harvesting systems. Researchers have successfully constructed various artificial light-harvesting systems through non-covalent assembly, including polymers, gels, biomaterials, and organic-inorganic hybrid materials. However, most reported artificial light-harvesting systems are constructed in organic solvents, rather than in an aqueous environment as in nature. Furthermore, since traditional donor chromophores are typically hydrophobic and exhibit aggregation-induced quenching (ACQ) in water, energy transfer efficiency is low, resulting in poor light-harvesting performance. Therefore, designing and constructing efficient artificial light-harvesting systems in aqueous solutions remains a challenging task. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention provides a method for preparing a carbazole-based aqueous artificial light-harvesting system and its application. This aqueous artificial light-harvesting system can maintain excellent energy transfer efficiency and antenna effect even with a high donor-acceptor ratio.
[0005] To achieve the above objectives, the technical solution of the present invention is as follows:
[0006] In a first aspect, the present invention provides a carbazole-based aqueous artificial light-harvesting system. This system is formed by supramolecular nanoparticles, which are formed by the host-guest interaction of compound G and compound H in an aqueous solution, and encapsulate fluorescent dye. In this system, compound G serves as the guest molecule and energy donor (Donor, Do), compound H serves as the host molecule, and fluorescent dye serves as the energy acceptor (Ac). Compound G and compound H form supramolecular nanoparticles in an aqueous solution through the host-guest interaction. By adding fluorescent dye, the supramolecular nanoparticles encapsulate the fluorescent dye to form the aqueous artificial light-harvesting system.
[0007] The chemical structural formula of compound G is shown in formula (I):
[0008]
[0009] The chemical structural formula of compound H is shown in formula (II):
[0010]
[0011] In a preferred embodiment, the fluorescent dye is sulforhodamine, whose chemical structural formula is shown in formula (III):
[0012]
[0013] In a preferred embodiment, the molar ratio of compound G to compound H in the aqueous artificial light-harvesting system is (0.25–20):1, for example, 0.25:1, 1:1, 2:1, 5:1, 10:1, 20:1 or any ratio therebetween.
[0014] Preferably, the molar ratio of compound G to fluorescent dye is (100-1000):1, for example 100:1, 150:1, 200:1, 250:1, 400:1, 500:1, 1000:1 or any ratio therebetween.
[0015] In some specific embodiments, the concentration of compound G in this aqueous artificial light-harvesting system is 1 × 10⁻⁶. -5 ~1×10 -4 mol / L; the concentration of compound H is 5 × 10⁻⁶ mol / L. -7 ~4×10 -4 mol / L; the concentration of the fluorescent dye is 1×10⁻⁶. -8 ~1×10 -6 mol / L.
[0016] Secondly, the present invention provides a method for preparing the above-mentioned aqueous artificial light-harvesting system, comprising the following steps:
[0017] Step 1: Dissolve compound G and compound H in an aqueous solution and sonicate to form a uniformly dispersed spherical supramolecular nanoparticle solution.
[0018] Step 2: Add the solution containing the fluorescent dye to the solution obtained in Step 1, and disperse by ultrasonication to obtain the aqueous artificial light-harvesting system.
[0019] Preferably, the solvent in the above-mentioned solution containing fluorescent dye is one of dimethyl sulfoxide, ethanol, N,N-dimethylformamide, and water.
[0020] Thirdly, the present invention provides the application of the above-mentioned aqueous artificial light-harvesting system in the preparation of luminescent materials.
[0021] Furthermore, the luminescent material is a photoluminescent material with an excitation wavelength of 250–450 nm.
[0022] Furthermore, the luminescent material is a color-tunable luminescent material.
[0023] In the technical solution of the present invention, under excitation light of 250-450nm, the molar concentration ratio of energy donor compound G to energy acceptor fluorescent dye is (100-1000):1, and the luminescent material exhibits a luminescent characteristic that changes from blue-green to red as the energy acceptor ratio increases.
[0024] In the technical solution of the present invention, 380nm excitation light is the maximum absorption wavelength of the energy donor G. Under excitation light outside 250-450nm, the energy donor cannot absorb the excitation light and cannot transfer energy.
[0025] The above technical solution has the following advantages or beneficial effects:
[0026] The aqueous artificial light-harvesting system provided by the present invention uses a phenylcarbazolyl-modified acrylonitrile derivative compound G as a guest molecule and energy donor, a phosphate-modified columnar aromatic compound H as a host molecule, and a fluorescent dye as an energy acceptor; compound G and compound H self-assemble into nanoparticles through supramolecular host-guest interactions, and then add fluorescent dye to form an aqueous artificial light-harvesting system.
[0027] Compared with the prior art, the present invention has the following technical effects:
[0028] (1) In the provided aqueous artificial light-harvesting system, compound G contains an aggregation-induced emission (AIE) active acrylonitrile group, which can not only act as a guest molecule to bind with the host compound H, but also act as an energy donor. Due to the AIE properties of G, the fluorescence of compound G is significantly enhanced in the presence of the host compound H. Compound H is a water-soluble columnar aromatic hydrocarbon, which can form a complex with compound G through host-guest interaction in the aqueous artificial light-harvesting system, and induce compound G to further self-assemble into nanoparticles. This provides nanocavities to encapsulate dye molecules and form a light-harvesting system while increasing the fluorescence intensity of compound G. This light-harvesting system is a water-dispersible nanoparticle constructed in water through host-guest interaction. It has the advantages of low cost, environmental friendliness, structural stability and long-term storage. The preferred dye for this light-harvesting system is sulforhodamine 101 (SR101), which can maintain good energy transfer even at a high donor-acceptor ratio, with an energy transfer efficiency of up to 75% and an antenna effect of 40%.
[0029] (2) The fluorescence color of the light-harvesting system provided by the present invention is adjustable. As the proportion of acceptors increases, it gradually changes from cyan-green fluorescence to red fluorescence. It is worth noting that significant white fluorescence emission can be modulated, which provides a reference for the preparation of new and efficient fluorescent materials. Attached Figure Description
[0030] Figure 1 The ultraviolet spectrum of compound G in Example 1;
[0031] Figure 2 The fluorescence spectra of the guest and the host at different concentration ratios in aqueous solution in Example 2;
[0032] Figure 3 The fluorescence spectra of energy donors and energy acceptors at different concentration ratios in Example 3 are shown in aqueous solution.
[0033] Figure 4 The fluorescence spectrum of energy transfer in Example 3;
[0034] Figure 5 The fluorescence spectrum of the antenna effect in Example 3;
[0035] Figure 6 The fluorescence spectrum of the white fluorescence in Example 3;
[0036] Figure 7 This is a fluorescence color transition diagram from Example 3;
[0037] Figure 8 This is the fluorescence color transition gamut (CIE) diagram from Example 3;
[0038] Figure 9The 1H NMR spectrum of compound G prepared in Example 1;
[0039] Figure 10 The image shows the carbon NMR spectrum of compound G prepared in Example 1. Specific implementation methods
[0040] The following embodiments are merely some, not all, of the embodiments of the present invention. Therefore, the detailed descriptions of the embodiments provided below are not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0041] In this invention, unless otherwise specified, all equipment and raw materials are commercially available or commonly used in the industry. The methods described in the following embodiments are conventional methods in the art, unless otherwise specified.
[0042] Example 1: Preparation of Guest Compound G
[0043] In this embodiment, compound G is synthesized from compound A, and the structural formula of compound A is as follows:
[0044]
[0045] The preparation of compound G was as follows: Compound A (100 mg, 0.28 mmol) and 4-(9H-carbazole-9-yl)benzaldehyde (78 mg, 0.28 mmol) were added to an ethanol solution containing tetrabutylammonium hydroxide (4 drops, 20 mL), and stirred overnight at room temperature. The mixture was centrifuged, and the solid product was collected. The solid product was washed three times with ethanol (30 mL in total), and dried by air to obtain compound B (152 mg, 0.25 mmol).
[0046] The structural formula of compound B is as follows:
[0047]
[0048] Compound B (100 mg, 0.17 mmol) and trimethylamine (98 mg, 1.7 mmol) were dissolved in 20 mL of ethyl acetate and stirred overnight at room temperature. The mixture was centrifuged, the solid product was collected, and then washed three times with anhydrous diethyl ether (60 mL in total). The product was dried over a blast furnace to give compound G (107 mg, 0.16 mmol).
[0049] The proton NMR spectrum of compound G is as follows: Figure 9 As shown: 1H NMR (DMSO-d6, 400MHz, 298K) δ (ppm): 8.29 (dd, J=22, 8Hz, 4H), 8.08 (s, 1H), 7.93–7.66 (m, 5H), 7.50–7.46 (m, 3H), 7.38–7.3 2(m,2H),7.11–7.05(m,2H),4.06(t,J=6.4Hz,2H),3.30–3.26(m,2H),3.05(s,9H),1.76–1.65(m,4H),1.43–1.31(m,12H).
[0050] The carbon NMR spectrum of compound G is as follows: Figure 10 As shown: 13 C NMR(DMSO-d6,100MHz,298K)δ(ppm):160.1,140.1,139.8,138.7,133.3,131.2,129.5,127.8,127.4,127.2,126.9, 126.4,123.5,121.1,121.0,118.6,115.6,110.6,110.3,68.2,65.7,52.6,29.4,29.2,29.1,29.0,26.2,26.0,22.5.
[0051] The structure of compound G was determined through the above experimental characterization as follows:
[0052]
[0053] like Figure 1 As shown, through ultraviolet spectroscopy testing, the ultraviolet absorption of compound G is in the 250-450 nm region, therefore the excitation wavelength range can be selected as 250-450 nm.
[0054] Example 2: Preparation of supramolecular nanoparticles
[0055] In this embodiment, compound H was synthesized according to the literature J. Colloid Interface Sci., 2023, 641, 803-811, and its structure is shown below:
[0056]
[0057] The preparation process of supramolecular nanoparticles is as follows:
[0058] Step 1: Weigh compound G prepared in Example 1 into a 5 mL volumetric flask, add dimethyl sulfoxide and bring the volume to 5 mL to prepare a 2×10⁻⁶ volumetric flask. -2 mol / L of mother liquor;
[0059] Step 2: Weigh compound H prepared in Example 2 into a 50 mL volumetric flask, add deionized water to make up to 50 mL, and prepare a solution of 4.2 × 10⁻⁶. -4 mol / L of mother liquor;
[0060] Step 3: Use a pipette to transfer 4 mL of deionized water into a 5 mL volumetric flask. Then, use a pipette to transfer appropriate amounts of the mother liquor of compound G and the mother liquor of compound H into volumetric flasks containing deionized water. After sonication for 3 min, aqueous-phase dispersed nanoparticles are formed. The concentration of compound G was 5 × 10⁻⁶. -5 The corresponding concentration ratios of compound G / compound H were 0.25:1, 1:1, 2:1, 5:1, 10:1, and 20:1, respectively.
[0061] In this embodiment, the ultrasonic instrument used is a commonly used laboratory ultrasonic cleaner with a frequency of 40kHz.
[0062] The fluorescence of the above-mentioned aqueous-dispersed nanoparticles was measured using a fluorescence spectrophotometer with an excitation wavelength of 365 nm. The corresponding fluorescence spectrum is shown below. Figure 2 As shown, the fluorescence peak of compound G is at 490 nm, while the fluorescence intensity of the nanoparticles at 490 nm reaches its maximum when the G:H ratio is 20:1. This indicates that compound H can significantly enhance the fluorescence intensity of compound G through host-guest interactions.
[0063] Example 3: Preparation of a light-harvesting system
[0064] In this embodiment, the fluorescent dye sulforhodamine 101 (SR101) is preferred as the energy acceptor (Ac), and compound G is preferred as the energy donor (Do).
[0065] Step 1: Weigh compound G prepared in Example 1 into a 5 mL volumetric flask, add dimethyl sulfoxide and bring the volume to 5 mL to prepare a 2×10⁻⁶ volumetric flask. -2 mol / L of mother liquor;
[0066] Step 2: Weigh compound H prepared in Example 2 into a 50 mL volumetric flask, add deionized water to make up to 50 mL, and prepare a solution of 4.2 × 10⁻⁶. -4 mol / L of mother liquor;
[0067] Step 3: Weigh the fluorescent dye acceptor Ac into a 5 mL volumetric flask, add dimethyl sulfoxide to bring the volume to 5 mL, and prepare a 2×10⁻⁶ volumetric flask. -4 mol / L of mother liquor;
[0068] Step 4: Use a pipette to transfer 4 mL of deionized water into a 5 mL volumetric flask. Then, use a pipette to transfer appropriate amounts of the mother liquor of compound G, the mother liquor of compound H, and the mother liquor of the fluorescent dye sulforhodamine 101 into volumetric flasks containing deionized water. After sonication for 3 min, aqueous-phase dispersed nanoparticles are formed. The concentration of compound G was 5 × 10⁻⁶. -5 The concentration of compound H is 2.5 × 10 mol / L. -6 The corresponding donor-acceptor ratios were 100:1, 150:1, 200:1, 250:1, 400:1, 500:1, and 1000:1, respectively.
[0069] The fluorescence of the above series of samples was measured using a fluorescence spectrophotometer with an excitation wavelength of 365 nm. The corresponding fluorescence spectra are as follows: Figure 3 As shown.
[0070] from Figure 3 As can be seen, the fluorescence intensity of compound G, which acts as the energy donor, at 490 nm gradually decreases with increasing concentration of energy acceptor Ac; while the fluorescence intensity of sulforhodamine 101, which acts as the energy acceptor, at 607 nm gradually increases with increasing concentration of energy acceptor Ac, indicating that it has good energy transfer and light capture effects.
[0071] The above energy transfer efficiency (Φ) ET The fluorescence spectrum was calculated using formula S1:
[0072] Φ ET =1-I DA / I D (eq.S1)
[0073] Among them, I DA and I D They are and When excited at 365 nm, the fluorescence intensity at 490 nm is ( Figure 4 ).
[0074] The antenna effect (AE) above is calculated from the fluorescence spectrum using formula S2:
[0075] AE = (I DA,365 –I D,365 ) / I DA,545 (eq.S2)
[0076] Among them, I DA,365 and I DA,545 They are Fluorescence intensity at 607 nm under excitation at 365 nm and 545 nm; ID,365 yes Normalized calculations at 490 nm yielded the fluorescence intensity at 607 nm. Figure 5 ).
[0077] Furthermore, observation under ultraviolet light revealed that as the concentration of the receptor Ac increased, the fluorescence color gradually shifted towards red, and after passing through white fluorescence (… Figure 6 and Figure 7 Converting the obtained fluorescence spectrum into coordinates on a color gamut diagram reveals that the color coordinates (0.32, 0.34) are very close to the pure white coordinates (0.33, 0.33), indicating that the prepared white fluorescence is of good quality. Figure 8 ).
[0078] The basic principles and main features of the present invention have been described above. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of the present invention is defined by the appended claims rather than the foregoing description, and thus all changes falling within the meaning and scope of the equivalents of the claims are intended to be included within the present invention. Although embodiments of the present invention have been described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A carbazole-based aqueous artificial light-harvesting system, characterized in that, The aqueous artificial light-harvesting system is formed by supramolecular nanoparticles containing fluorescent dyes, which are formed by host-guest interactions between compounds G and H in an aqueous solution. The chemical structural formula of compound G is shown below: ； The chemical structural formula of compound H is shown below: ； The fluorescent dye is sulforhodamine, and its chemical structural formula is shown below: ； The molar ratio of compound G to compound H is (0.25~20):1; The molar ratio of compound G to the fluorescent dye is (100-1000):
1.
2. A method for preparing the aqueous artificial light harvesting system as described in claim 1, characterized in that, Includes the following steps: S1. Dissolve compound G and compound H in an aqueous solution and sonicate to form a uniformly dispersed supramolecular nanoparticle solution; S2. Add the solution containing the fluorescent dye to the supramolecular nanoparticle solution and disperse by ultrasonication to obtain the aqueous artificial light-harvesting system.
3. The preparation method according to claim 2, characterized in that, The solvent in the solution containing the fluorescent dye is one of dimethyl sulfoxide, ethanol, N,N-dimethylformamide, and water.
4. The application of the aqueous artificial light-harvesting system as described in claim 1 in the preparation of luminescent materials.
5. The application according to claim 4, characterized in that, The luminescent material is a photoluminescent material with an excitation wavelength of 250–450 nm.
6. The application according to claim 4, characterized in that, The luminescent material is a color-tunable luminescent material, with a color range from cyan to red.