A three-component hydrogen-bonded organic framework material and its preparation method and application

Abstract

The present invention belongs to the technical field of hydrogen bond organic framework materials, and relates to a three-component hydrogen bond organic framework material and its preparation method and application. The chemical formula is: {C 26 H 21 O 12 P4·(CH6N3)·(C 10 H 12 N4)·(H2O)} n , where n is a positive integer. The structural unit belongs to the triclinic system, the space group is P-1, and the molecular formula is C 37 H 41 N7O 13 P4, each repeating unit contains a water molecule, a G + cation, a DBpy 2+ Cationic and an H5TPE 3‑ Molecule; G + Amino groups on cations, DBpy 2+ Amino groups on cations, H5TPE 3‑ Deprotonated HPO3 in the molecule ‑ The three-component strategy greatly expands the chemical and structural diversity of HOFs and achieves significant improvements in material properties.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen-bonded organic framework materials, and in particular relates to a three-component hydrogen-bonded organic framework material and a preparation method and application thereof. Background Art

[0002] Direct methanol fuel cells (DMFCs) can directly convert chemical energy into electrical energy, and have the advantages of high energy conversion efficiency, high energy density, clean and low emissions. Proton exchange membranes (PEMs), one of the core components of DMFCs, mainly play the role of proton transfer and fuel barrier. The excellent proton transport capacity and good stability of PEMs are the key to achieving high-efficiency DMFCs. The proton conductivity of commercial Nafion is significantly reduced at high temperature and low relative humidity (RH), and the methanol barrier efficiency becomes lower. By optimizing and modifying Nafion by doping with inorganic substances, its proton conductivity, output power density and chemical stability can be improved, thereby effectively promoting the development of DMFCs. Therefore, the preparation of Nafion-based PEMs with excellent comprehensive performance is crucial to the development of fuel cells.

[0003] Hydrogen-bonded organic frameworks (HOFs) are a class of crystalline organic polymers formed by hydrogen bonding interactions and self-assembly of organic molecular units. Since hydrogen bonds exhibit weaker and more flexible interactions, it is challenging to achieve strong and porous HOFs. In proton-conducting materials, the designability and high surface area of ​​crystalline materials provide opportunities for the orderly accommodation of proton carriers. At the same time, the inherent hydrogen bonding network of HOFs provides a natural transport site for protons. Therefore, HOFs have great potential for use as proton-conducting materials. It is worth noting that HOFs have inherent advantages such as high crystallinity, good solution processability, regeneration and simple recrystallization healing. These unique properties enable HOFs to be used in DMFCs.

[0004] Typical HOFs are very simple, referring to organic frameworks composed of identical organic molecules with hydrogen bond donors / acceptors. Such frameworks are usually formed by single organic monomers interconnected by hydrogen bonds. Since hydrogen bonding is a weak interaction force, the structural stability of single-component HOFs may be low and easily affected by the external environment, which limits their application in proton conduction. Therefore, in recent years, researchers have used two organic molecules with different charges to construct more robust ionic HOFs (iHOFs) through charge-assisted hydrogen bonding. These materials further improve stability through the interaction of hydrogen bonds and ionic bonds. At the same time, the acid-base organic molecules in the structure can effectively act as proton carriers, promote proton migration, and thus significantly improve the proton conductivity of the material.

[0005] In contrast, two-component crystals exhibit superior performance due to their complex structures and ionic bonding interactions. However, the electrical conductivity of two-component HOFs structures still needs to be improved, which has driven the exploration and demand for more complex structural designs. The synthesis of multi-component metal-organic frameworks (MOFs) and covalently bonded covalent organic frameworks (COFs) has been widely used in structural construction, while the exploration of multi-component HOFs is still in its infancy. Compared with the strongly coordinated MOFs and covalently bonded COFs, HOFs mainly rely on weaker hydrogen bonding interactions to maintain their structure.

[0006] Therefore, when synthesizing multi-component HOFs, maintaining charge balance becomes more complicated and the difficulty of synthesis increases accordingly. Summary of the Invention

[0007] One of the purposes of the present invention is to provide a three-component hydrogen-bonded organic framework material and a preparation method thereof, which solves the problem of complex charge balance and high synthesis difficulty when synthesizing multi-component HOFs.

[0008] The second purpose of the present invention is to provide an application of a three-component hydrogen-bonded organic framework material. After the three-component hydrogen-bonded organic framework material is prepared into a proton exchange membrane, the proton exchange membrane is applied to DMFCs, thereby improving the power density and current density.

[0009] The present invention is achieved through the following technical solutions:

[0010] A three-component hydrogen-bonded organic framework material with the chemical formula:

[0011] {C 26 H 21 O 12 P4·(CH6N3)·(C 10 H 12 N4)·(H2O)} n , where n is a positive integer.

[0012] Furthermore, the structural unit of the three-component hydrogen bond organic framework material belongs to the triclinic system, the space group is P-1, and the molecular formula is C 37 H 41 N7O 13 P4, unit cell parameters: α=69.3128(13)°, β=85.5750(15)°, γ=72.2037(16)°,

[0013] Furthermore, the three-component hydrogen bond organic framework material is polymerized by multiple repeating units, each repeating unit contains a water molecule, a G +cation, a DBpy 2+ Cationic and an H5TPE 3- molecular.

[0014] Further, G + Amino groups on cations, DBpy 2+ Amino groups on cations, H5TPE 3- Deprotonated HPO3 in the molecule - The phosphonic acid groups cooperate with the unprotonated phosphonic acid groups and water molecules to form a two-dimensional hydrogen bond network.

[0015] Furthermore, the three-component hydrogen-bonded organic framework material is a porous material, and its thermal stability temperature reaches 240°C.

[0016] Furthermore, the three-component hydrogen bond organic framework material has a maximum impedance of 17Ω at 98% relative humidity and 100°C, and a conductivity of 1.81×10 -2 S cm -1 ;

[0017] At 98% relative humidity and low temperature a =0.27eV, E under high temperature conditions a =0.78eV.

[0018] The present invention also discloses a method for preparing the three-component hydrogen-bonded organic framework material, comprising the following steps:

[0019] 1) Dissolve guanidine hydrochloride in N,N'-dimethylacetamide to form solution A;

[0020] Dissolve 1,1′-diamino-4,4′-bipyridyl diiodide in ethanol to form solution B;

[0021] dissolving tetrakis(4-phosphonophenyl)ethylene in water to form solution C;

[0022] The molar ratio of guanidine hydrochloride, 1,1′-diamino-4,4′-bipyridyl diiodide, and tetrakis(4-phosphonophenyl)ethylene is 15-20:5:1;

[0023] The three solutions were mixed to form a mixed solution, and the mixture was reacted at 80-120° C. for 72 h to obtain a reaction solution;

[0024] 2) The reaction solution obtained in step 1) is allowed to stand at room temperature to obtain yellow needle-shaped crystals, which are then naturally dried to obtain the three-component hydrogen-bonded organic framework material.

[0025] The present invention also discloses the application of the three-component hydrogen-bonded organic framework material. After the three-component hydrogen-bonded organic framework material is prepared into a proton exchange membrane, the proton exchange membrane is applied to a direct methanol fuel cell.

[0026] Furthermore, the specific steps of preparing the three-component hydrogen-bonded organic framework material into a proton exchange membrane are as follows:

[0027] 1) dispersing the three-component hydrogen-bonded organic framework material in isopropanol and stirring to obtain a suspension;

[0028] Add Nafion solution to the suspension and continue stirring at room temperature to obtain a uniform solution;

[0029] The mass of the three-component hydrogen-bonded organic framework material is 3% to 9% of the mass of the Nafion solution;

[0030] 2) pouring the obtained stirred solution into a culture dish and drying it at room temperature to remove the solution to obtain a composite membrane;

[0031] 3) At 80° C., the composite membrane was sequentially soaked in H 2 O 2 and washed with deionized water; soaked in a sulfuric acid solution for one hour, washed with deionized water until the pH of the membrane surface was neutral, and dried at room temperature to obtain a proton exchange membrane.

[0032] Compared with the prior art, the present invention has the following beneficial technical effects:

[0033] The present invention discloses a three-component hydrogen bond organic framework material. The main innovation of the material is the synthesis of [(H5TPE)·(DBpy)·G·(H2O)] n Compared to the more widely studied HOFs, the key innovation of three-component hydrogen-bonded organic frameworks lies in their breakthrough of the limitations of traditional single- and two-component HOFs, exploring for the first time the construction of three-component HOFs. This three-component strategy not only greatly expands the chemical and structural diversity of HOFs but also significantly enhances material performance by integrating the properties of multiple functional groups. This invention not only introduces new research directions to the HOF field but also provides new ideas and methods for developing materials with more complex functions and higher performance.

[0034] Furthermore, PXRD powder diffraction analysis data showed that the obtained product had high purity, thermogravimetric analysis showed high thermal stability, the decomposition temperature of the three-component porous framework was 240°C, and it also had high proton conductivity, indicating that it was a new type of proton conductive material.

[0035] The present invention also discloses a method for preparing the three-component hydrogen-bonded organic framework material, in which H8TPE, G·HCl and DBpy·2I are selected as ligands. G·HCl is rich in nitrogen and hydrogen atoms, and its molecular chain length is compact, which can promote the dense arrangement of hydrogen bonds, which not only optimizes the interaction between molecules, but also improves the proton conduction efficiency of the material. The DBpy·2I molecule has an inherent aromatic structure and molecular rigidity, and the aromatic core structure is thermally stable and chemically inert, laying a solid foundation for the construction of supramolecular systems. Phosphonic acid ligands are selected. Compared with the HOFs with sulfonic acid and carboxylic acid as ligands that have been studied more in the past, the phosphonic acid group contains two protons and three oxygen atoms, which enables H8TPE to release protons through a variety of deprotonation modes, thereby establishing charge-assisted hydrogen bonds with different proton acceptors. This preparation method has a simple process and low synthesis difficulty. The prepared three-component hydrogen-bonded organic framework material not only has excellent stability but also achieves high proton conductivity.

[0036] When the three-component hydrogen bond organic framework is doped into Nafion as a proton conductive material, the conductivity can reach 1.81×10 -2 S cm -1 When used as a proton exchange membrane in a direct methanol fuel cell, the maximum power density reaches 80.78 mW·cm -2 , maximum current density 499.22 mA·cm -2 Compared with the commercial Nafion membrane, the prepared proton exchange membrane has improved power density and current density, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of the structural unit of the three-component hydrogen-bonded organic framework material synthesized in Example 4 of the present invention;

[0038] Figure 2 The hydrogen bond network structure of the hydrogen bond organic framework material synthesized in Example 4 of the present invention;

[0039] Figure 3 This is a schematic diagram of the three-dimensional structure of the hydrogen-bonded organic framework material synthesized in Example 4 of the present invention;

[0040] Figure 4 The X-ray powder diffraction pattern of the hydrogen-bonded organic framework material crystal synthesized in Example 4 of the present invention;

[0041] Figure 5 This is a thermogravimetric analysis diagram of the hydrogen-bonded organic framework material crystal synthesized in Example 4 of the present invention;

[0042] Figure 6 This is the impedance diagram of the hydrogen-bonded organic framework material synthesized in Example 4 of the present invention;

[0043] Figure 7 This is an activation energy analysis diagram of the hydrogen-bonded organic framework material synthesized in Example 4 of the present invention;

[0044] Figure 8 This is a diagram of the power density and current density of DMFC at 80°C for the proton exchange membrane prepared in Example 4 of the present invention. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the present invention more clear, the following is a further detailed description with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. That is, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0046] The components described and illustrated in the drawings and embodiments of the present invention may be arranged and designed in a variety of different configurations. Therefore, the detailed description of the embodiments of the present invention provided in the following drawings is not intended to limit the scope of the claimed invention, but merely represents a selected embodiment of the present invention. All other embodiments derived by those skilled in the art based on the drawings and embodiments of the present invention without inventive effort shall fall within the scope of protection of the present invention.

[0047] It should be noted that the terms "comprises", "includes" or any other variations are intended to cover non-exclusive inclusion, so that a process, element, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to the process, element, method, article or apparatus.

[0048] The present invention discloses a three-component hydrogen bond organic framework material, the chemical formula of which is: {C 26 H 21 O 12 P4·(CH6N3)·(C 10 H 12 N4)·(H2O)} n , where n is a positive integer.

[0049] The present invention also discloses a method for preparing the hydrogen-bonded organic framework material, comprising the following steps:

[0050] 1) Using G·HCl, DBpy·2I, and H8TPE as raw materials, G·HCl was dissolved in N,N'-dimethylacetamide to form solution A; DBpy·2I was dissolved in ethanol to form solution B; and H8TPE was dissolved in water to form solution C;

[0051] The molar ratio of guanidine hydrochloride, 1,1′-diamino-4,4′-bipyridyl diiodide, and tetrakis(4-phosphonophenyl)ethylene is 15-20:5:1;

[0052] The three solutions were mixed to form a mixed solution, and the mixture was reacted at 80-120° C. for 72 h to obtain a reaction solution;

[0053] Among them, H8TPE is tetrakis(4-phosphonophenyl)ethylene, DBpy·2I is 1,1′-diamino-4,4v-bipyridyl diiodide, G·HCl is guanidine hydrochloride, and DMA is N,N′-dimethylacetamide.

[0054] 2) The reaction solution obtained in step 1) was allowed to stand at room temperature to obtain yellow needle-shaped crystals, which were then naturally dried to obtain a three-component hydrogen-bonded organic framework material.

[0055] Compared with the extensive research on single-component and two-component HOFs, three-component HOFs have not been fully explored. n It is a three-component hydrogen bond organic framework material. In this material, G + The short chain length and abundant active sites form a dense hydrogen bond network, which facilitates proton transport. Furthermore, the inherent aromatic structure and molecular rigidity of the DBpy·2I molecule further enhance the structural stability of the entire framework. This combination of properties not only provides advantages for proton conduction but also lays the foundation for the development of new multifunctional materials.

[0056] By utilizing the interactions between different ligand functional groups, we have successfully achieved multifunctional integration of HOFs. This strategy not only enhances the stability and proton conductivity of the material, but also provides a new approach for designing HOFs with specific properties.

[0057] The features and performance of the present invention are further described in detail below with reference to the embodiments.

[0058] Example 1

[0059] The present invention discloses a method for preparing a three-component hydrogen-bonded organic framework material, comprising the following steps:

[0060] 1) G·HCl, DBpy·2I, and H8TPE ligand were weighed in a molar ratio of 10:5:1;

[0061] G·HCl was dissolved in N,N'-dimethylacetamide to form solution A; DBpy·2I was dissolved in ethanol to form solution B; H8TPE was dissolved in water to form solution C;

[0062] The three solutions were mixed to form a mixed solution, and the mixture was reacted at 80° C. for 72 h to obtain a reaction solution;

[0063] 2) The reaction solution obtained in step 1) was allowed to stand at room temperature to obtain yellow needle-shaped crystals, which were naturally dried to synthesize [(H5TPE)·(DBpy)·G·(H2O)] n Three-component hydrogen-bonded organic framework materials.

[0064] The yield of the three-component hydrogen-bonded organic framework material obtained in this embodiment is 48%.

[0065] Example 2

[0066] The present invention discloses a method for preparing a three-component hydrogen-bonded organic framework material, comprising the following steps:

[0067] 1) G·HCl, DBpy·2I, and H8TPE ligand were weighed in a molar ratio of 15:5:1;

[0068] G·HCl was dissolved in N,N'-dimethylacetamide to form solution A; DBpy·2I was dissolved in ethanol to form solution B; H8TPE was dissolved in water to form solution C;

[0069] The three solutions were mixed to form a mixed solution, and the mixture was reacted at 100° C. for 60 h to obtain a reaction solution;

[0070] 2) The reaction solution obtained in step 1) was allowed to stand at room temperature to obtain yellow needle-shaped crystals, which were naturally dried to synthesize [(H5TPE)·(DBpy)·G·(H2O)] n Three-component hydrogen-bonded organic framework materials.

[0071] The yield of the three-component hydrogen-bonded organic framework material obtained in this example is 56%.

[0072] Example 3

[0073] The present invention discloses a method for preparing a three-component hydrogen-bonded organic framework material, comprising the following steps:

[0074] 1) G·HCl, DBpy·2I, and H8TPE ligand were weighed in a molar ratio of 20:5:1;

[0075] G·HCl was dissolved in N,N'-dimethylacetamide to form solution A; DBpy·2I was dissolved in ethanol to form solution B; H8TPE was dissolved in water to form solution C;

[0076] The three solutions were mixed to form a mixed solution, and the mixture was reacted at 100° C. for 48 h to obtain a reaction solution;

[0077] 2) The reaction solution obtained in step 1) was allowed to stand at room temperature to obtain yellow needle-shaped crystals, which were naturally dried to synthesize [(H5TPE)·(DBpy)·G·(H2O)] n Three-component hydrogen-bonded organic framework materials.

[0078] The yield of the three-component hydrogen-bonded organic framework material obtained in this embodiment is 62%.

[0079] Example 4

[0080] The present invention discloses a method for preparing a three-component hydrogen-bonded organic framework material, comprising the following steps:

[0081] 1) G·HCl, DBpy·2I, and H8TPE ligand were weighed in a molar ratio of 20:5:1;

[0082] G·HCl was dissolved in N,N'-dimethylacetamide to form solution A; DBpy·2I was dissolved in ethanol to form solution B; H8TPE was dissolved in water to form solution C;

[0083] The three solutions were mixed to form a mixed solution, and the mixture was reacted at 120° C. for 72 h to obtain a reaction solution;

[0084] 2) The reaction solution obtained in step 1) was allowed to stand at room temperature to obtain yellow needle-shaped crystals, which were naturally dried to synthesize [(H5TPE)·(DBpy)·G·(H2O)] n Three-component hydrogen-bonded organic framework materials.

[0085] The yield of the three-component hydrogen-bonded organic framework material obtained in this embodiment is 67%.

[0086] In the above embodiments, Example 4 is taken as the best embodiment. The three-component hydrogen bond organic framework material prepared in Example 4 is monochromated on a Bruke smart APEXIICCD diffractometer using a graphite monochromator to monochromate Mo Kα The ray was scanned in ω-θ mode at 298K, and the diffraction points were collected. The F2 was modified by full matrix least squares analysis using SHELXL=2014 software package. The material belongs to the triclinic system, the space group is P-1, and the molecular formula is C 37 H 41 N7O 13 P4, unit cell parameters: α=69.3128(13)°, β=85.5750(15)°, γ=72.2037(16)°,

[0087] The three-component hydrogen bond organic framework material is composed of multiple repeating units, each of which contains a water molecule, a G + cation, a DBpy 2+ Cationic and an H5TPE 3- Molecule. G + Amino groups on cations, DBpy 2+ Amino groups on cations, H5TPE 3- Deprotonated HPO3 in the molecule - The phosphonic acid groups cooperate with the unprotonated phosphonic acid groups and water molecules to form a two-dimensional hydrogen bond network.

[0088] like Figure 1-Figure 3 As shown in the figure, the remarkable structural feature of this material is that a three-component iHOF with unique structure and function was successfully constructed by designing a multi-component charge-assisted hydrogen bond self-assembly strategy. In this three-component hydrogen bond organic framework material, G + The short chain length and abundant active sites form a dense hydrogen bond network, which is conducive to proton transport. The DBpy·2I molecule has an inherent aromatic structure and molecular rigidity, which enables it to be stable in strong acidic and alkaline environments for one month.

[0089] like Figure 4 As shown, the powder diffraction data of the obtained three-component hydrogen-bonded organic framework material powder sample and the single crystal were compared, and it was found that the diffraction peaks of the obtained three-component hydrogen-bonded organic framework material were consistent with the peaks simulated by the single crystal structure data, indicating that the purity of the obtained material powder sample was relatively high, and also proved that the experimental reproducibility of the sample was good.

[0090] like Figure 5 As shown in Figure 2, the thermal stability of the three-component hydrogen-bonded organic framework material was determined by thermogravimetric analysis. The thermogravimetric analysis curve shows that the three-dimensional structure of the three-component hydrogen-bonded organic framework material can be stabilized up to 240°C. This indicates that the prepared material has good thermal stability and is a new material with practical application value.

[0091] The impedance of the three-component hydrogen bond organic framework material of the present invention at 98% RH and 90°C is as follows: Figure 6 As shown in the figure, the maximum impedance value is 17Ω. According to the relationship between impedance and conductivity, the conductivity of the material reaches 1.81×10 -2 S cm -1 .

[0092] Depend on Figure 7 The activation energy curve shows that under 98% RH and low temperature conditions, E a =0.27eV, E under high temperature conditions a =0.78eV, which is consistent with the Grotthuss mechanism.

[0093] After the three-component hydrogen-bonded organic framework material is prepared into a proton exchange membrane, the proton exchange membrane is applied to DMFCs, which has better battery performance.

[0094] The present invention also discloses a method for preparing the proton exchange membrane, comprising the following steps:

[0095] 1) dispersing the three-component hydrogen-bonded organic framework material in isopropanol and stirring for several hours to obtain a suspension;

[0096] Add Nafion solution to the suspension and continue stirring at room temperature for 6 hours to obtain a uniform solution. The mass of the three-component hydrogen-bonded organic framework material is 3% to 9% of the mass of the Nafion solution.

[0097] 2) pouring the obtained stirred solution into a culture dish and drying it at room temperature for 24 hours to remove the solution to obtain a composite membrane;

[0098] 3) At 80° C., the composite membrane was sequentially soaked in 3 wt % H 2 O 2 for one hour and washed with deionized water; soaked in 1 M sulfuric acid solution for one hour and washed with deionized water until the pH of the membrane surface was neutral, and dried at room temperature to obtain a proton exchange membrane.

[0099] The present invention is described in further detail below in conjunction with the embodiments:

[0100] Example 5

[0101] 1) Dispersing 18 mg of the three-component hydrogen-bonded organic framework material in isopropanol and stirring for 2 hours to obtain a suspension;

[0102] 3 g of 20% Nafion solution was added to the suspension, and the mixture was stirred at room temperature for 6 hours to obtain a uniform solution.

[0103] 2) pouring the obtained stirred solution into a Petri dish and drying it at room temperature for 24 hours to remove the solvent to obtain a composite membrane;

[0104] 3) At 80° C., the composite membrane was sequentially soaked in 3 wt % H 2 O 2 for one hour and washed with deionized water; soaked in 1 M sulfuric acid solution for one hour and washed with deionized water until the pH of the membrane surface was neutral, and dried at room temperature to obtain a proton exchange membrane.

[0105] The conductivity of the proton exchange membrane obtained in this example is 1.81×10 -2 S cm -1 .

[0106] Example 6

[0107] 1) Dispersing 27 mg of the three-component hydrogen-bonded organic framework material in isopropanol and stirring for 2 hours to obtain a suspension;

[0108] 3 g of 20% Nafion solution was added to the suspension, and the mixture was stirred at room temperature for 6 hours to obtain a uniform solution.

[0109] 2) pouring the obtained stirred solution into a Petri dish and drying it at room temperature for 24 hours to remove the solvent to obtain a composite membrane;

[0110] 3) At 80° C., the composite membrane was sequentially soaked in 3 wt % H 2 O 2 for one hour and washed with deionized water; soaked in 1 M sulfuric acid solution for one hour and washed with deionized water until the pH of the membrane surface was neutral, and dried at room temperature to obtain a proton exchange membrane.

[0111] The conductivity of the proton exchange membrane obtained in this example is 0.93×10 -2 S cm -1 .

[0112] Example 7

[0113] 1) Dispersing 9 mg of the three-component hydrogen-bonded organic framework material in isopropanol and stirring for 2 hours to obtain a suspension;

[0114] 3 g of 20% Nafion solution was added to the suspension, and the mixture was stirred at room temperature for 6 hours to obtain a uniform solution.

[0115] 2) pouring the obtained stirred solution into a Petri dish and drying it at room temperature for 24 hours to remove the solvent to obtain a composite membrane;

[0116] 3) At 80° C., the composite membrane was sequentially soaked in 3 wt % H 2 O 2 for one hour and washed with deionized water; soaked in 1 M sulfuric acid solution for one hour and washed with deionized water until the pH of the membrane surface was neutral, and dried at room temperature to obtain a proton exchange membrane.

[0117] The conductivity of the proton exchange membrane obtained in this example is 3.23×10 -3 S cm -1 .

[0118] Among the above examples 5-7, example 5 is taken as the best example. The proton exchange membrane prepared in example 5 is applied to DMFC for testing. The power density of the proton exchange membrane and the recast Nafion membrane (from 50.49 mW·cm -2 to 80.78 mW·cm -2 ) Maximum current density (from 312.01mA·cm -2 to 499.22 mA·cm -2 ) were both increased by 60%.

[0119] In summary, the three-component hydrogen-bonded organic framework material synthesized in the present invention exhibits strong stability in both strong acidic and strong alkaline solutions through the synergistic effect of the components, and maintains the proton conductivity at 1.81×10 -2 S cm -1 high level, and it has a two-dimensional hydrogen bond network.

[0120] In addition, the self-assembly property of the three-component hydrogen-bonded organic framework allows the composition of the ligands to be adjusted to optimize their performance. By mixing with Nafion, a proton exchange membrane was obtained. At 100 °C and 98% RH, the maximum proton conductivity of the proton exchange membrane with a 9% three-component hydrogen-bonded organic framework doping ratio can reach 1.55×10 -2 S cm -1 , which is 3.8 times that of recast Nafion.

[0121] like Figure 8 As shown in Figure 2, the proton exchange membrane was applied to DMFC, and the maximum current density was 499.22 mA cm -2 , the peak power density is 80.78mW·cm -2 , which is 1.6 times that of recast Nafion membrane. With this unique flexibility and adjustability, multi-component HOFs have great application potential in the field of fuel cells.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A three-component hydrogen-bonded organic framework material, characterized in that: The chemical formula of the three-component hydrogen bond organic framework material is: 26 H 21 O 12 P4·(CH6N3)·(C 10 H 12 N4)·(H2O)} n , where n is a positive integer; The three-component hydrogen bond organic framework material is composed of multiple repeating units, each of which contains a water molecule, a G + cation, a DBpy 2+ Cationic and an H5TPE 3- molecular; G + Amino groups on cations, DBpy 2+ Amino groups on cations, H5TPE 3- Deprotonated HPO3 in the molecule - The phosphonic acid groups cooperate with the unprotonated phosphonic acid groups and water molecules to form a two-dimensional hydrogen bond network.

2. A three-component hydrogen-bonded organic framework material according to claim 1, characterized in that: The structural unit of the three-component hydrogen-bonded organic framework material belongs to the triclinic system, and the space group is P- 1, molecular formula is C 37 H 41 N7O 13 P4, unit cell parameters: a = 11.4485(6) Å, b =14.2971 (7) Å, c = 15.6798(8) Å, α = 69.3128(13)°, β =85.5750(15)°, γ = 72.2037(16)°, V = 2284.7(2) Å 3 .

3. The three-component hydrogen-bonded organic framework material according to claim 1, characterized in that: The three-component hydrogen bond organic framework material is a porous material, and its thermal stability temperature reaches 240°C.

4. A three-component hydrogen-bonded organic framework material according to claim 1, characterized in that: The three-component hydrogen-bonded organic framework material has a maximum impedance of 17 Ω at 98% relative humidity and 100°C, and a conductivity of 1.81 × 10 - 2 S cm -1 .

5. The method for preparing the three-component hydrogen-bonded organic framework material according to any one of claims 1 to 4, characterized in that: The following steps are involved: 1) Dissolve guanidine hydrochloride in N,N' -dimethylacetamide to form solution A; Dissolve 1,1ʹ-diamino-4,4ʹ-bipyridinium diiodide in ethanol to form solution B; dissolving tetrakis(4-phosphonophenyl)ethylene in water to form solution C; The molar ratio of guanidine hydrochloride, 1,1ʹ-diamino-4,4ʹ-bipyridyl diiodide, and tetrakis(4-phosphonophenyl)ethylene is 15-20:5:1; The three solutions were mixed to form a mixed solution, and the mixture was reacted at 80-120 °C for 72 h to obtain a reaction solution; 2) The reaction solution obtained in step 1) is allowed to stand at room temperature to obtain yellow needle-shaped crystals, which are then naturally dried to obtain the three-component hydrogen-bonded organic framework material.

6. Use of the three-component hydrogen-bonded organic framework material according to any one of claims 1 to 4, characterized in that: After the three-component hydrogen-bonded organic framework material is prepared into a proton exchange membrane, the proton exchange membrane is applied to a direct methanol fuel cell.

7. The use of the three-component hydrogen-bonded organic framework material according to claim 6, characterized in that: The specific steps for preparing the three-component hydrogen-bonded organic framework material into a proton exchange membrane are as follows: 1) dispersing the three-component hydrogen-bonded organic framework material in isopropanol and stirring to obtain a suspension; Add Nafion solution to the suspension and continue stirring at room temperature to obtain a uniform solution; Among them, the mass of the three-component hydrogen-bonded organic framework material is 3% to 9% of the mass of the Nafion solution; 2) pouring the obtained stirred solution into a Petri dish and drying it at room temperature to remove the solution to obtain a composite membrane; 3) At 80°C, the composite membrane was sequentially soaked in H2O2 and washed with deionized water; soaked in sulfuric acid solution for one hour, washed with deionized water until the pH of the membrane surface was neutral, and dried at room temperature to obtain a proton exchange membrane.

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