A spherical host-guest type metal organic hybrid material for single-color multimode laser output and a preparation method thereof

Abstract

The application discloses a kind of for single-color multimode laser output spherical host-guest type micro-nano laser and its preparation method, the micro-nano laser is by the spherical metal organic hybrid material host with distortion topological network structure and laser dye guest composition.Wherein the composition of spherical metal organic hybrid material host is:Zn, organic ligand 2,4,6-tri (3,5-dicarboxyphenyl amino) -1,3,5-triazine, N,N-dimethylformamide.Guest is laser dye.The application is based on spherical metal organic hybrid material as the resonant cavity of micro-nano laser, utilizes its super-smooth surface and excellent circular boundary, avoids boundary scattering loss, effectively provides sufficient feedback for laser oscillation, realizes single-color multimode laser output with high quality factor, narrow half-width, wide mode interval and low laser threshold.Effectively solve the problem that existing micro-nano laser is mostly crystal material, and there is a lot of boundary scattering loss.

Description

Technical Field

[0001] This invention relates to the field of organic-inorganic hybrid laser materials technology, and to a spherical metal-organic hybrid material and its preparation method, particularly to a spherical host-guest type metal-organic hybrid material for monochromatic multimode laser output and its preparation method. Background Technology

[0002] Micro- and nano-lasers are miniature lasers that achieve laser output at the micro- and nano-scale. These ideal ultra-small laser sources currently have very broad application prospects in a range of fields. Micro- and nano-lasers are commonly used in chemical and biomedical engineering, such as biosensors, photo-driven therapy, and photocatalytic drug release. They are also widely used in optical computing, information storage, optical communication, and nanoanalysis. Research on these micro- and nano-lasers is based on micro- and nano-photonics, which is essentially a discipline that studies the interaction of light and matter at the micro- and nano-scale. It has not only opened up new fields for fundamental research but also created opportunities for the emergence and development of high technologies. Its interdisciplinary nature and technological applications extend to many fields, including physics, chemistry, materials science, electronic information, and biomedicine.

[0003] Metal-organic frameworks (MOFs) are novel three-dimensional porous crystalline materials formed by bridging metal ions or metal ion clusters with multidentate organic ligands. These materials possess characteristics such as ordered pore structure, tunable pore size, and large specific surface area. Combining the processability of organic materials with the stability of inorganic materials, they have become a highly attractive platform for constructing micro / nano lasers.

[0004] Organic laser dyes exhibit strong luminescence but suffer from aggregation quenching, resulting in weak luminescence in the solid state. However, introducing fluorescent molecules into the channels of metal-organic frameworks (MOFs) can effectively mitigate or even prevent this aggregation quenching. This is because the channel structure of MOFs greatly restricts intramolecular rotational motion, increases structural stiffness, thereby reducing the probability of nonradiative transitions and improving luminescence efficiency and stability. Furthermore, the ultra-high crystal surface quality and diverse topological structures of MOFs can serve as resonant cavities, one of the three essential elements of laser luminescence. Therefore, MOFs have attracted numerous researchers to use them as platforms for constructing powerful micro / nano lasers. Currently, a large number of publications report the use of MOFs to achieve laser output. In addition, various MOF microstructures, including 1D micro / nanowires, 2D micro / nanosheets, and 3D multi-topological polyhedral structures, have also been reported for realizing Fabry-Perot mode (FP) or whispering-gallery-mode (WGM) resonant cavity lasers.

[0005] However, micro / nano lasers based on MOF single-crystal materials have rigid, multi-edge boundaries due to the anisotropy of crystal growth. The non-smooth edge boundaries between different planes cause strong scattering losses, thus affecting laser output and hindering the further development of MOF-based micro / nano lasers. To address this, flexible ligand molecules are used as a framework to achieve topological distortion and collapse. This retains the advantages of metal-organic framework materials while ensuring isotropic growth of the material into a spherical structure with continuous, smooth surfaces under the influence of solvent surface tension. Eliminating this edge scattering loss and improving laser output quality through this simple and low-cost method is of great significance and presents a challenging problem for the future research and development of micro / nano lasers based on metal-organic framework materials. Summary of the Invention

[0006] The purpose of this invention is to provide a spherical host-guest type metal-organic hybrid material (MOF) for monochromatic multimode laser output and its preparation method. A novel spherical MOF with a distorted topological network structure serves as the laser resonant cavity, eliminating edge scattering losses widely present in metal-organic framework-based micro / nano lasers. The solution for eliminating edge scattering losses in this invention utilizes flexible ligands to achieve a topologically distorted amorphous structure in MOFs during growth, obtaining uniformly shaped spherical micro / nano particles through isotropic growth. The spherical microcavity can tightly confine photons with total internal reflection, thereby eliminating edge scattering losses and improving laser output quality.

[0007] This preparation method primarily involves the coordination synthesis of the flexible, multidentate carboxylic acid organic ligand 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine (H6TDPAT) with the metal hydrate Zn(NO3)2·6H2O. A guest organic laser dye is added during the synthesis of the host hybrid material via in-situ growth, resulting in a one-step host-guest type metal-organic hybrid material loaded with the organic laser dye. This enables micro / nano lasers that can achieve high-quality laser output with narrow full width at half maximum (FWHM), wide mode spacing, and low laser threshold. Compared to other laser materials, this invention obtains a laser material with a spherical resonant cavity possessing a topological distortion network through a simple synthesis method, avoiding edge scattering losses and improving laser quality.

[0008] The objective of this invention is achieved in the following ways:

[0009] A spherical host-guest type metal-organic hybrid material for monochromatic multimode laser output is composed of a spherical metal-organic hybrid material host with a distorted topological network structure and a laser dye guest. The spherical metal-organic hybrid material is amorphous and its composition includes: Zn element, organic ligands 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine, and N,N-dimethylformamide; the laser dye is loaded into the spherical metal-organic hybrid material.

[0010] In this spherical host-guest type metal-organic hybrid material, the proportion of Zn element is 12-13%, and the proportion of laser dye is 13-15%.

[0011] The laser dye can be an organic laser dye DMASM, which has maximum absorption in the 350-600 nm region and maximum emission in the 600-650 nm region, and its emission is broadband red light. The organic laser dye DMASM can be replaced by one of the following: methyl 2-[6-ethylamino)-3-ethylimino-2,7-dimethyl-3H-oxacyclohexane-9-yl]benzoate perchlorate (R590), ethyl 2-[6-ethylamino)-3-ethylimino-2,7-dimethyl-3H-oxacyclohexane-9-yl]benzoate perchlorate (R6G), 1-ethyl-4-[4-(p-dimethylaminophenyl)-1,3-butadienyl]pyridine (DABP), and 9-(2-carboxyphenyl)-3,6-bis(diethylamino)zanthonium chloride (RB). The absorption region of the ligand H6TDPAT in this spherical metal-organic hybrid material is the 300-400 nm ultraviolet region. Therefore, a 532 nm laser is selected as the pump source, which ensures that the pump source is within the maximum absorption wavelength range of the organic laser dye DMASM, while avoiding absorption of the pump source by the organic ligand H6TDPAT. This avoids competition caused by absorption, improves absorption efficiency, and lowers the laser threshold. The wavelength range of the pump source can be 400 nm to 540 nm, and it can output monochromatic multimode laser.

[0012] The preparation method of the spherical host-guest type metal-organic hybrid material with monochromatic multimode laser output of the present invention is as follows:

[0013] In-situ one-step preparation of spherical host-guest type metal-organic hybrid laser materials loaded with organic laser dyes

[0014] The polydentate carboxylic acid organic ligand 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine was dissolved in a zinc hydrate in an organic solvent. The organic laser dye was added to the above mixed solution and ultrasonically dispersed. The ultrasonically dispersed reaction solution was placed in a polytetrafluoroethylene-lined reaction vessel. The reaction vessel was then placed in a stainless steel bottle and placed in an oven for reaction. After the reaction was completed, the sample was separated by vacuum filtration and washed three or more times with N,N-dimethylformamide and ethanol. It was then dried in air and collected to obtain a host-guest type organometallic hybrid material with a spherical morphology loaded with organic laser dye.

[0015] In the above scheme, the ratio of the amount of the polydentate carboxylic acid organic ligand, zinc, organic laser dye and organic solvent is 0.1-0.3mM: 0.5-1.5mM: 0.05-0.2mM: 10-20mL.

[0016] Furthermore, the zinc hydrate is Zn(NO3)2·6H2O, ZnCl2, or Zn(BF4)2 hydrate.

[0017] Furthermore, the organic solvent is any one or a mixture of several of N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, methanol, ethanol, dioxane, and acetone.

[0018] The beneficial effects of this invention are as follows:

[0019] 1. By utilizing the mature micro / nano laser platform—metal-organic framework materials—and through reasonable design and control, metal-organic hybrid materials with good stability can be obtained. These materials are then matched with organic ligands or guest materials with rich photonic properties. This allows for the selection of D-π-A type dyes with excellent performance and high photon absorption cross-sections, effectively ensuring the reliability of the laser dye and efficient laser output.

[0020] 2. Based on the mature micro / nano laser platform—metal-organic framework materials—amorphous spherical metal-organic hybrid materials were obtained through improvements in synthesis methods and organic ligands. By selecting suitable organic ligands with flexible structures, isotropic crystal growth was achieved. Utilizing the flexibility of the ligands, amorphous spherical metal-organic hybrid materials with distorted topological networks were obtained. The smooth spherical surface effectively avoided the unavoidable edge scattering loss caused by the rough edges between different crystal planes, effectively limiting photon loss within the microcavity and significantly improving laser quality.

[0021] 3. In the selection of laser dyes and organic ligands, the optimal absorption regions of laser dyes and organic ligands are effectively avoided to be in the same wavelength range. By reasonably selecting the pump wavelength, the competitive absorption of organic ligands on the pump light source can be effectively avoided, and efficient laser output can be obtained in the end.

[0022] 4. The partial pore structure and molecular confinement structure of metal-organic hybrid materials can effectively restrict the intramolecular rotational motion of organic laser dyes, thereby reducing the probability of nonradiative transitions, avoiding the aggregation quenching effect of the dye itself, improving the luminescence efficiency of organic laser dyes, and the isolation effect of the pores can effectively reduce the influence of environmental factors on organic laser dyes and improve their stability.

[0023] 5. The present invention provides a simple fabrication process for micro / nano lasers based on host-guest type metal-organic hybrid materials. Furthermore, by controlling the concentration of the precursor solution, the ratio of metal ions, organic ligands, and organic laser dyes in the precursor solution, and the reaction time, micro / nano lasers of different sizes, doping concentrations, and surface morphologies can be constructed using a spherical metal-organic framework as a platform. Attached Figure Description

[0024] Figure 1 The PXRD patterns of the spherical amorphous metal-organic framework material before and after loading with laser dye in Example 1 are shown.

[0025] Figure 2 The thermogravimetric analysis (TGA) diagrams of the material before and after loading with laser dye in Example 1 are shown.

[0026] Figure 3 The images shown are SEM images of the material in Example 1 at different reaction times and temperatures.

[0027] Figure 4 The BET (a, c) and pore size analysis (b, d) of the material before and after loading with laser dye in Example 1 are shown.

[0028] Figure 5 The image shows a laser confocal microscopy image of the material after loading with laser dye in Example 1. Different focal planes of the microspheres were scanned sequentially from top to bottom, with a distance of 2 μm between the planes.

[0029] Figure 6 The fluorescence intensity of the laser dye with different N,N-dimethylformamide solution concentrations in Example 1 is shown in (a), the fluorescence intensity-dye concentration standard curve is shown in (b), and the fluorescence intensity curve of the laser dye loaded on the material is shown in (c).

[0030] Figure 7 10% of the laser dye in Example 1 -4Fluorescence intensity curves of M DMF solution (corresponding to DMASM solution in the figure), DMASM powder, and the material obtained in Example 1 under the same conditions;

[0031] Figure 8 These are optical micrographs of the material in Example 1 before and after loading with laser dye, taken under a bright-field optical microscope and a dark-field optical microscope, respectively. (a) and (b) are images without laser dye loading, and (c) and (d) are images after laser dye loading.

[0032] Figure 9 (a) is the laser spectrum obtained by the laser material in Example 1 under irradiation by pump sources with different energy densities at 532 nm. (b) shows the dependence of the emission intensity (red) and spectral linewidth (blue) of the laser material on the pump energy. The intersection of the red linear dependence curves (red asterisk) is the laser threshold: 43.5 μJ / cm. 2 (c) represents a dark-field laser photograph of the laser material achieving laser emission, with a scale bar of 10 μm. Figure 10 (a), (b), and (c) are microscopic images of microspheres with different diameters (L = 17.00 μm, 12.34 μm, and 6.63 μm) in Example 1. (d) shows the laser spectra corresponding to microspheres with different diameters. (e) shows the relationship between the laser adjacent mode interval Δλs and the microsphere diameter L, oriented towards the WGMs feedback mechanism, based on the function Δλs = λ 2 / πn g L is a linear fit, λ represents the resonant wavelength of the laser, and n g This represents the group refractive index of the microsphere. Detailed Implementation

[0033] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. Technical features in the various embodiments of the present invention can be combined accordingly without mutual conflict.

[0034] Example 1:

[0035] In-situ one-step preparation of spherical metal-organic frameworks loaded with organic laser dyes for laser materials

[0036] 0.2 mmol of the polydentate carboxylic acid organic ligand 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine and 1.0 mmol of zinc hydrate were dissolved in 10 mL of N,N-dimethylformamide organic solvent. 0.05 mmol of E-4-(4-dimethylaminostyryl)-1-ethylpyridinium (DMASM) was added to the above mixed solution. The mixture was ultrasonically dispersed for 30 min. The ultrasonically dispersed reaction solution was placed in a polytetrafluoroethylene-lined reaction vessel. The reaction vessel was then placed in a stainless steel bottle and placed in an oven at 120 °C for 24 h. After the reaction, the sample was separated by vacuum filtration, washed three or more times with N,N-dimethylformamide and ethanol, dried in air and collected to obtain a metal-organic hybrid material loaded with organic laser dye (denoted as DMASM@AMOHM), which is a laser material with a spherical resonant cavity.

[0037] Simultaneously, a sample without the laser dye DMASM (denoted as AMOHM) was also prepared for this example. It also exhibited a spherical structure. The PXRD patterns of the spherical metal-organic framework material before and after loading the laser dye are shown below. Figure 1 As shown, they all exhibit amorphous peaks, representing distorted topological network structures.

[0038] Corresponding BET and pore size analysis diagrams are as follows Figure 4 Laser confocal microscopy images such as Figure 5 As shown in the figure; BET analysis reveals that the CO2 adsorption capacity of DMASM@AMOHM after dye loading is significantly lower than that of AMOHM, indicating that the laser dye occupies the distorted channels of AMOHM; laser confocal microscopy images show the uniform distribution of the laser dye DMASM in the microspheres. Combined analysis shows that the dye is uniformly distributed within the channels of the microspheres.

[0039] Furthermore, spherical laser materials prepared at different reaction times and temperatures were investigated, such as... Figure 3 As shown, spherical laser materials can be obtained by reacting at 80–120℃ for 6–36 hours.

[0040] The proportion of Zn in the product obtained by this invention can be determined by ICP (ion concentration testing); the proportion of laser dye is as follows: Figure 6 The results can be obtained through absorbance testing; the thermogravimetric analysis of the product obtained in this example is as follows. Figure 2 At temperatures below 300℃, the organic solvent molecule N,N-dimethylformamide volatilizes, from which the mass percentage of the organic solvent can be roughly estimated to be about 20%.

[0041] The laser material obtained in the examples can emit laser output in the wavelength range of 600-650 nm, which is within the red light wavelength range. The laser emission threshold is 43.5 μJ·cm. -2The mode spacing Δλ between laser modes is approximately 12.52 nm, and the full-width at half-maximum (FWHM) narrows to 1.39 nm. Based on calculations, the laser quality factor Q is approximately 450. This is calculated using the formula Δλ = λ 2 / (Ln g The group refractive index n of the synthesized laser material was calculated. g Approximately 1.84; see the detailed laser emission pattern for details. Figure 9 .

[0042] This laser material, due to its smooth surface and unique spherical topology, can effectively prevent aggregation. (See...) Figure 8 Light micrographs of non-agglomerated samples under bright-field and dark-field conditions. Based on this, future research could explore the possibility of achieving matrix laser output through the rational arrangement of dots in this material, applicable to laser displays, laser coding, and laser anti-counterfeiting.

[0043] Figure 10 Microscopic images of microspheres with different diameters (L = 17.00 μm, 12.34 μm, and 6.63 μm) and their corresponding laser spectra in Example 1 show that the laser adjacent mode interval Δλs has a strong dependence on the microsphere diameter L. (e) This dependence is represented by a linear fitting curve, i.e., the relationship between the laser adjacent mode interval Δλs and the microsphere diameter L, oriented towards the WGMs feedback mechanism, according to the function Δλs = λ 2 / πn g L is a linear fit, λ represents the resonant wavelength of the laser, and n g This represents the group refractive index of the microsphere.

[0044] Example 2:

[0045] In-situ one-step preparation of spherical metal-organic frameworks loaded with organic laser dyes for laser materials

[0046] 0.2 mmol of the polydentate carboxylic acid organic ligand 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine and 1.0 mmol of zinc hydrate were dissolved in 10 mL of N,N-dimethylformamide organic solvent. 0.05 mmol of 9-(2-carboxyphenyl)-3,6-bis(diethylamino) thionyl chloride (RB) was added to the above mixed solution. The mixture was ultrasonically dispersed for 30 min. The ultrasonically dispersed reaction solution was placed in a polytetrafluoroethylene-lined reaction vessel. The reaction vessel was then placed in a stainless steel bottle and placed in an oven at 120 °C for 24 h. After the reaction, the sample was separated by vacuum filtration and washed three or more times with N,N-dimethylformamide and ethanol. The sample was then dried in air and collected to obtain a metal-organic hybrid material with an organic laser dye and a spherical resonant cavity.

[0047] This laser material can emit laser output in the wavelength range of 600-630 nm, which is within the red light wavelength range. The laser emission threshold is 52.00 μJ·cm⁻¹. -2 The mode spacing Δλ between laser modes is approximately 13.96 nm, and the full-width at half-maximum (FWHM) narrows to 1.12 nm. Based on calculations, the laser quality factor Q is approximately 536. This is calculated using the formula Δλ = λ 2 / (Ln g The group refractive index n of the synthesized laser material was calculated. g It is approximately 2.02.

[0048] The embodiments described above are merely some preferred embodiments of the present invention, and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A spherical host-guest type metal-organic hybrid material for monochromatic multimode laser output, characterized in that, The material comprises a spherical metal-organic hybrid with a distorted topological network structure as the host and a laser dye as the guest. The spherical metal-organic hybrid is amorphous and consists of Zn, the organic ligand 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine, and N,N-dimethylformamide. The laser dye is loaded onto the spherical metal-organic hybrid. The spherical host-guest type metal-organic hybrid loaded with the organic laser dye is prepared in situ via a one-step method, specifically including the following: The polydentate carboxylic acid organic ligand 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine was dissolved in a zinc hydrate in an organic solvent. An organic laser dye was added to the above mixed solution and ultrasonically dispersed. The ultrasonically dispersed reaction solution was placed in a polytetrafluoroethylene-lined reaction vessel. The reaction vessel was then placed in a stainless steel bottle and placed in an oven for reaction. After the reaction was completed, the product was separated by vacuum filtration and washed three or more times with N,N-dimethylformamide and ethanol. The product was dried in air and collected to obtain a host-guest type organometallic hybrid material with a spherical morphology loaded with organic laser dye. The ratio of the polydentate carboxylic acid organic ligand, zinc, organic laser dye, and organic solvent is 0.1-0.3 mmol: 0.5-1.5 mmol: 0.05-0.2 mmol: 10-20 mL; the organic solvent is N,N-dimethylformamide.

2. The spherical host-guest type metal-organic hybrid material for monochromatic multimode laser output according to claim 1, characterized in that, The spherical host-guest type metal-organic hybrid material contains 12-13% Zn and 13-15% laser dye.

3. A method for preparing a spherical host-guest type metal-organic hybrid material for monochromatic multimode laser output as described in claim 1, characterized in that, This involves the in-situ one-step preparation of spherical host-guest type metal-organic hybrid materials loaded with organic laser dyes, specifically including the following: The polydentate carboxylic acid organic ligand 2,4,6-tris(3,5-dicarboxyphenylamino)-1,3,5-triazine was dissolved in a zinc hydrate in an organic solvent. An organic laser dye was added to the above mixed solution and ultrasonically dispersed. The ultrasonically dispersed reaction solution was placed in a polytetrafluoroethylene-lined reaction vessel. The reaction vessel was then placed in a stainless steel bottle and placed in an oven for reaction. After the reaction was completed, the product was separated by vacuum filtration and washed three or more times with N,N-dimethylformamide and ethanol. The product was dried in air and collected to obtain a host-guest type organometallic hybrid material with a spherical morphology loaded with organic laser dye. The ratio of the polydentate carboxylic acid organic ligand, zinc, organic laser dye, and organic solvent is 0.1-0.3 mmol: 0.5-1.5 mmol: 0.05-0.2 mmol: 10-20 mL; the organic solvent is N,N-dimethylformamide.

4. The method for preparing a spherical host-guest type metal-organic hybrid material for monochromatic multimode laser output according to claim 3, characterized in that, The zinc hydrates mentioned are Zn(NO3)2·6H2O, ZnCl2, and Zn(BF4)2 hydrate.

5. The method for preparing a spherical host-guest type metal-organic hybrid material for monochromatic multimode laser output according to claim 3, characterized in that, The organic laser dye is one of E-4-(4-dimethylaminostyryl)-1-ethylpyridinium (DMASM), methyl 2-[6-ethylamino)-3-ethylimino-2,7-dimethyl-3H-oxacyclohexane-9-yl]benzoate perchlorate (R590), ethyl 2-[6-ethylamino)-3-ethylimino-2,7-dimethyl-3H-oxacyclohexane-9-yl]benzoate perchlorate (R6G), 1-ethyl-4-[4-(p-dimethylaminophenyl)-1,3-butadienyl]pyridine (DABP), and 9-(2-carboxyphenyl)-3,6-bis(diethylamino)zanthonium chloride (RB).

6. A micro / nano laser, characterized in that, Using the material as described in claim 1, monochromatic multimode laser is output under a pump light source with a wavelength of 400nm~540nm.

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