CN115006573A

CN115006573A - Multifunctional degerming nanopore COF aerogel and preparation method thereof

Info

Publication number: CN115006573A
Application number: CN202210587990.8A
Authority: CN
Inventors: 林辉; 朱凯成
Original assignee: Suzhou Iante New Material Technology Co ltd
Current assignee: Suzhou Iante New Material Technology Co ltd
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2022-09-06
Anticipated expiration: 2042-05-26
Also published as: CN115006573B

Abstract

The invention discloses a multifunctional degerming nanopore COF aerogel and a preparation method thereof, the multifunctional degerming nanopore COF aerogel comprises porous COFs, metal ions, guanidino and polyimide are arranged on the porous COFs, the metal ions are Ag +, an organic ligand I of the COFs is placed in an organic solvent to prepare an organic ligand I-organic solvent solution, precursor polyamide acid of guanidino polymer and polyimide is added for stirring, then silane coupling agent is added to form a mixed solution, a gel promoter is added into the mixed solution to form precursor wet sol, the precursor wet sol is placed in an organic solvent for synthesizing an organic ligand II of the COFs to be converted into COFs wet sol, after-synthesis modification method, the functional Ag + nano ions are loaded in the COFs wet sol to generate guanidino/polyimide/Ag + -COFs wet sol, then gel reaction is carried out to prepare guanidino/polyimide/Ag + -COFs wet gel, and aging and drying to obtain the multifunctional COF aerogel containing guanidino/polyimide/Ag +.

Description

Multifunctional degerming nanopore COF aerogel and preparation method thereof

Technical Field

The invention relates to the technical field of aerogel, and particularly relates to multifunctional degerming nanopore COF aerogel and a preparation method thereof.

Background

The common degerming aerogel generally comprises a single component with degerming function, for example, for inorganic degerming components, typically represents nanometer Ag + with excellent performance, for organic degerming components, such as organic mercury, organic zinc, chlorophenols, organic bromides and the like, but organic mercury, organic zinc and phenolic bactericides have high bactericidal effect but are extremely toxic, and the organic bromides are too irritant and are not ideal choices, and the degerming rate is always a problem to be improved.

Disclosure of Invention

In order to solve the defects in the prior art, the invention provides a multifunctional degerming nanopore COF aerogel and a preparation method thereof.

In order to realize the technical effects, the invention adopts the following scheme:

a multifunctional degerming nanoporous COF aerogel comprises porous COFs, wherein metal ions, guanidino and polyimide are arranged on the porous COFs, and the metal ions are Ag +.

A preparation method of a multifunctional degerming nanopore COF aerogel comprises the following steps:

s1, placing an organic ligand I of COFs in an organic solvent, stirring for 3-5 min on a mechanical stirrer at 18-25 ℃ with the rotating speed of a stirring rod controlled to be 250-350 r/min, and preparing an organic ligand I-organic solvent solution;

s2, adding guanidyl polymer and polyimide precursor polyamic acid into the organic ligand I-organic solvent solution system, and stirring for 3-5 min on a magnetic stirrer at the temperature of 20-25 ℃ and at the rotating speed of 350-500 rpm;

s3, adding a silane coupling agent into the solution obtained after stirring in the step S2 to form a mixed solution, and then carrying out ultrasonic reaction in an ultrasonic dispersion instrument at the temperature of 20-25 ℃ for 10-15 min;

s4, adding a gel accelerator into the mixed solution obtained in the step S3, and then carrying out ultrasonic treatment on the mixed solution and an ultrasonic dispersion instrument at the temperature of 20-25 ℃ for 5-15 min to homogenize the mixed solution to form precursor wet sol;

s5, putting the precursor wet sol prepared in the step S4 in an organic solvent for synthesizing an organic ligand II of the COFs, stirring for 15-20 min until the precursor wet sol is white and milky, standing for 3-5 min, then locally heating for 2-4 h by microwaves to enable the organic ligand I and the organic ligand II of the COFs to complete self-assembly reaction, and converting the precursor wet sol into the COFs wet sol;

s6, carrying out loading of functional Ag + nano ions in the COFs wet sol by a post-synthesis modification method to generate guanidino/polyimide/Ag + -COFs wet sol;

s7, putting the prepared guanidine group/polyimide/Ag + -COFs wet sol into a drying oven for carrying out gel reaction at 40-60 ℃ for 1-3 hours to prepare guanidine group/polyimide/Ag + -COFs wet gel;

s8, putting the guanidyl/polyimide/Ag + -COFs wet gel in an organic solvent for aging for 48-72 h;

s9, drying the aged guanidine group/polyimide/Ag < + > -COFs wet gel to obtain multifunctional COF aerogel of guanidine group/polyimide/Ag < + >.

In the preferable technical scheme, the ratio of the organic ligand I to the organic solvent in the step S1 is 0.01-1: 1;

in a preferred embodiment, the organic solvent in step S1 is: a mixed organic solvent of tetrahydrofuran and N, N-dimethylacetamide; the organic ligand I of the COFs is one of trimesic aldehyde, terephthalaldehyde, tetra (4-formylbenzene) methane, tetra-formyl phenyl porphyrin, 3',5,5' -tetra-formyl biphenyl, 1,2,4, 5-tetra (4-formylphenyl) benzene, 2 '-bipyridine-5, 5' -dicarboxaldehyde, 2, 5-dihydroxy terephthalic acid, 2, 5-dimethoxy benzene-1, 4-dicarboxaldehyde, 2, 6-naphthalene dicarboxaldehyde and 1,3, 5-tri (4-aminophenyl) benzene.

In a preferred embodiment, the guanidino polymer in step S2 is polyhexamethylene biguanide hydrochloride.

In a preferred technical scheme, the guanidino polymer and the polyimide precursor polyamic acid added in the step S2 are 0.1-10% of the organic ligand i-organic solvent solution system in terms of volume ratio.

In a preferred technical scheme, the amount of the silane coupling agent added in the step S3 is 0.1-5% of the volume of the stirred solution obtained in the step S2.

In a preferred technical scheme, the silane coupling agent added in step S3 is: propyl triethoxysilane, octyl trimethoxysilane, octyl triethoxysilane, dodecyl trimethoxysilane, dodecyl methyldimethoxysilane, and hexadecyl trimethoxysilane.

In a preferable technical scheme, in the step S4, the dosage of the gel promoter is controlled to be 10-40% of the mixed solution according to the volume ratio.

In a preferred embodiment, the gel accelerator in step S4 is propylene oxide.

In the preferable technical scheme, in the step S5, the volume ratio of the organic ligand II to the organic ligand I is 0.8-1.2: 1.

in a preferred embodiment, the organic ligands ii of the COFs used in step S5 are: one of phenylenediamine, melem, 1,3, 5-triaminobenzene, biphenyldiamine, 5,15- (aminophenyl) -10, 20-phenylporphyrin, tetrakis (4-aminophenyl) methane, tris (4-aminophenyl) amine, 5 '-diamino-2, 2' -bipyridine, 2,4, 6-tris (4-aminophenoxy) -1,3, 5-triazine, 1,3, 5-tris (4-aminophenyl) benzene, 4, 4-methylenetetranilide, 2,3,5, 6-tetrafluoroterephthalic acid formaldehyde; the organic solvents used were: one of ethanol, methanol and dimethylformamide.

In a preferred technical scheme, the specific operation steps of loading the functional Ag + nano-ions in step S6 are as follows: and (3) putting the prepared COFs wet sol into an organic solution containing Ag salt, carrying out ultrasonic treatment for 2-5 min, then oscillating the mixed solution on a shaking table for 15-25 min, then putting the mixed solution into a microwave reactor, controlling the microwave reaction rate, reacting for 45min, then heating in water bath at 45-60 ℃ for 6-12 h, and fully completing the loading of Ag & lt + & gt on the COFs to generate the guanidyl/polyimide/Ag & lt + & gt-COFs wet gel.

In a preferred embodiment, the silver salt in step S6 is silver nitrate.

In a preferred embodiment, the organic solvent used in step S8 is methanol.

In a preferred embodiment, the drying method used in step S9 is: one of freeze drying and supercritical drying.

Compared with the prior art, beneficial effect does:

1. the thought mode of traditional sterilization by using a single component is broken through, the concept of a metal-covalent organic framework (M-COF) is creatively applied to the field of aerogels, and a novel material structure with the cooperative sterilization of multiple organic and inorganic components is prepared by using guanidyl and comparing and selecting metal ions M (Ag +) so as to seek the maximization and the optimal solution of the sterilization effect, thereby realizing the result of 1+1> 2;

2. the COFs of the gel material are changed, and the prepared new material endows the conventional gel with the micropore characteristic which is difficult to have, so that the porosity and the surface area of the gel are increased, the adsorption performance of the gel is improved, and the sterilization efficiency is enhanced;

3. the COFs gel light material made of light elements (B, C, O, N) has the advantage of low self-weight of the structure;

4. the introduction of the high-performance material polyimide makes up the defects of physical and chemical properties of guanidyl, and in addition, the material has the advantages of heat resistance and sustainable use, namely the material can be recycled through ultrasonic washing.

Drawings

FIG. 1 is a flow chart of a production process in the present invention;

FIG. 2 is a preparation process of the present invention;

FIG. 3 is a graph of the results of the antibacterial test;

fig. 4 is a graph of the results of the persistent antimicrobial test.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

s4, adding a gel promoter into the mixed solution obtained in the step S3, and then carrying out ultrasonic treatment on the mixed solution and an ultrasonic dispersion instrument at the temperature of 20-25 ℃ for 5-15 min to homogenize the mixed solution to form precursor wet sol;

In a preferred embodiment, the guanidinyl polymer in step S2 is polyhexamethylene biguanide hydrochloride.

In a preferred embodiment, the gel accelerator in step S4 is propylene oxide.

In a preferred embodiment, the silver salt in step S6 is silver nitrate.

In a preferred embodiment, the organic solvent used in step S8 is methanol.

Covalent Organic Frameworks (COFs) are a new class of new materials newly developed after inorganic porous materials and MOFs, and are a new class of crystalline porous Organic framework materials which are discovered by Yaghi and other colleagues in 2005 and are formed by connecting light elements (such as B, C, O, N) through Covalent bonds, and the materials have good structural flexibility, high specific surface area, adjustable porosity, precise periodicity, high chemical stability, easy molecular level functional design and the like.

As the COFs have micropores and good adjustable modification performance, the possibility is provided for preparing the material with the micropore-mesopore hierarchical pore structure by combining the COFs and the aerogel. In addition, compared with common porous materials such as MOFs, molecular sieves and the like, COFs further show a highly stable structure under the harsh chemical environments of boiling water, strong acid, strong alkali, oxidation and reduction conditions and the like, so that the defects of single composition, poor crystal form and the like of inorganic porous materials are overcome, the problems of high-temperature stability difference and easiness in collapse in water of the MOFs are solved, and the novel material prepared from the MOFs has a wider application range.

Example 1

(1) A solution of organic ligands I of COFs was prepared by adding 0.5ml of 2, 5-dihydroxyterephthalic acid to 10ml of a mixed organic solvent of tetrahydrofuran and DMAc (5 ml of each of tetrahydrofuran and DMAc) and stirring at 22 ℃ for 3min on a mechanical stirrer with the rotation speed of the stirrer bar controlled at 250 rpm to form a clear solution.

(2) Adding 0.30ml of polyhexamethylene biguanide hydrochloride and 0.30ml of PAAs into the clear solution, controlling the rotating speed in a magnetic stirrer at 20 ℃ to 400 r/min, and stirring for 5min until the solution is uniformly stirred;

(3) adding 0.106ml of silane coupling agent propyl triethoxysilane into the obtained solution, and dispersing in an ultrasonic disperser at 20 deg.C for 10min to form a mixed solution;

(4) adding 1.07ml of gel accelerator propylene oxide into the obtained solution, and carrying out ultrasonic treatment in an ultrasonic dispersion instrument at 25 ℃ for 10min to homogenize the solution to form precursor wet sol;

(5) adding the precursor wet sol obtained in the step (4) into a methanol solution containing 20ml, adding 0.5ml of organic ligand II 5,5 '-diamino-2, 2' -bipyridine of COFs, stirring for 15min until the solution is white and milky, standing for 3min until the solution is stable, then locally heating for 2h by microwave to allow two organic ligands of COFs to be self-assembled to form Covalent Organic Frameworks (COFs), and converting the precursor wet sol into the COFs wet sol;

(6) loading Ag + in the sol by a post-synthesis modification method, putting the COFs wet sol into 50ml of methanol solution, adding 1.02g of AgNO3, carrying out ultrasonic treatment for 2min, then putting the COFs wet sol on a shaking table to vibrate for 20min, then putting the COFs wet sol into a microwave reactor to react for 45min, and then heating the COFs in a water bath at 50 ℃ for 6h to fully complete the loading of Ag + on the COFs to generate guanidino/polyimide/Ag + -COFs wet sol;

(7) putting the guanidine group/polyimide/Ag < + > -COFs wet sol obtained in the step (6) into a closed mold, and carrying out gel reaction in an oven at the temperature of 60 ℃ to form guanidine group/polyimide/Ag < + > -COFs wet gel;

(8) adding a methanol solution into the guanidine group/polyimide/Ag < + > -COFs wet gel obtained in the step (7) for aging, wherein the volume of the aging solution is 100mL, and the aging time is 72 hours;

(9) putting the guanidine group/polyimide/Ag < + > -COFs wet gel obtained after aging in the step (8) into a high-pressure reaction kettle of a supercritical drying device, pumping CO2 into the high-pressure reaction kettle when the temperature of the high-pressure reaction kettle reaches 45 ℃, when the pressure of the high-pressure reaction kettle reaches 15MPa, enabling the system to reach a supercritical state, and maintaining the supercritical state for 120 minutes for drying; and after drying is finished, slowly discharging CO2 in the high-pressure reaction kettle, opening the kettle under the normal pressure state, and cooling the reaction kettle to the room temperature to obtain the guanidyl/polyimide/Ag + multifunctional COF aerogel.

Example 2

(1) Preparing a solution of organic ligands I of COFs, adding 0.6ml of tetra-aldehyde phenyl porphyrin into 10ml of mixed organic solvent of tetrahydrofuran and DMAc (wherein the tetrahydrofuran and the DMAc are 5ml respectively), and stirring for 3min on a mechanical stirrer at the temperature of 20 ℃ under the condition of controlling the rotating speed of a stirring rod to be 20 revolutions per minute to form a clear solution.

(2) Adding 0.31ml of polyhexamethylene biguanide hydrochloride and 0.29ml of PAAs into the clear solution, controlling the rotating speed in a magnetic stirrer at 22 ℃ to 400 r/min, and stirring for 5min until the solution is uniformly stirred;

(3) adding 0.108ml of silane coupling agent dodecyl trimethoxy silane into the obtained solution, and dispersing in an ultrasonic disperser at 20 ℃ for 10min to form a mixed solution;

(4) adding 1.17ml of a gel accelerator propylene oxide into the obtained solution, and carrying out ultrasonic treatment in an ultrasonic dispersion instrument at 25 ℃ for 10min to homogenize the solution to form precursor wet sol;

(5) adding the precursor wet sol obtained in the step (4) into a methanol solution containing 20ml, adding 0.5ml of organic ligands II 2,4, 6-tris (4-aminophenoxy) -1,3, 5-triazine of COFs, stirring for 15min until the solution is white and milky, standing for 3min until the solution is stable, then locally heating for 3h by microwaves, allowing two organic ligands of the COFs to be self-assembled to form Covalent Organic Frameworks (COFs), and converting the precursor wet sol into a COFs wet sol;

(6) loading Ag + in COFs wet sol by a post-synthesis modification method, putting the COFs wet sol solution into 50ml of methanol solution, adding 1.02g of AgNO3, carrying out ultrasonic treatment for 3min, then putting the COFs wet sol solution on a shaking table, vibrating for 15min, then putting the COFs wet sol solution into a microwave reactor, reacting for 45min, heating in a water bath at 60 ℃ for 8h, and fully completing the loading of Ag + on COFs to generate guanidino/polyimide/Ag + -COFs wet sol;

Example 3

(1) Preparing a solution of an organic ligand I of COFs, adding 0.55ml of 2,2 '-bipyridine-5, 5' -diformaldehyde into 10ml of a mixed organic solvent of tetrahydrofuran and DMAc (wherein the tetrahydrofuran and the DMAc are 5ml respectively), and stirring for 5min on a mechanical stirrer at the temperature of 20 ℃ under the condition of controlling the rotating speed of a stirring rod to be 250 revolutions per minute to form a clear solution;

(2) adding 0.27ml of polyhexamethylene biguanide hydrochloride and 0.27ml of PAAs into the clear solution, controlling the rotating speed in a magnetic stirrer at the temperature of 22 ℃ to be 450 r/min, and stirring for 5min until the solution is uniformly stirred;

(3) adding 0.105ml of silane coupling agent octyl trimethoxy silane into the obtained solution, and dispersing in an ultrasonic disperser at 20 ℃ for 10min to form a mixed solution;

(4) adding 1.10ml of a gel accelerator propylene oxide into the obtained solution, and carrying out ultrasonic treatment in an ultrasonic dispersion instrument at the temperature of 22 ℃ for 10min to homogenize the solution to form precursor wet sol;

(5) adding the precursor wet sol obtained in the step (4) into a methanol solution containing 20ml, adding 0.56ml of organic ligands II 5,15- (aminophenyl) -10, 20-phenylporphyrin of COFs, stirring for 20min until the solution is white and milky, standing for 3min until the solution is stable, then locally heating for 4h by microwaves to allow two organic ligands of COFs to self-assemble to form covalent organic frameworks COFs, and converting the precursor wet sol into the COFs wet sol;

(6) loading Ag + in COFs wet sol by a post-synthesis modification method, putting the COFs wet sol solution into 50ml of methanol solution, adding 1.23g of AgNO3, carrying out ultrasonic treatment for 2min, then putting the COFs wet sol solution on a shaking table, vibrating for 15min, then putting the COFs wet sol solution into a microwave reactor, reacting for 45min, heating in a water bath at 45 ℃ for 6h, and fully completing the loading of Ag + on COFs to generate guanidino/polyimide/Ag + -COFs wet sol;

(9) putting the guanidine group/polyimide/Ag < + > -COFs wet gel obtained after aging in the step (8) into a high-pressure reaction kettle of a supercritical drying device, pumping CO2 into the high-pressure reaction kettle when the temperature of the high-pressure reaction kettle reaches 45 ℃, when the pressure of the high-pressure reaction kettle reaches 15MPa, enabling the system to reach a supercritical state, and maintaining the supercritical state for 120 minutes for drying; and after drying is finished, slowly discharging CO2 in the high-pressure reaction kettle, opening the reaction kettle under the normal pressure state, and cooling the reaction kettle to the room temperature to obtain the guanidino/polyimide/Ag + multifunctional COF aerogel.

Example 4

(1) Preparing a solution of organic ligands I of COFs, adding 0.58ml of 3,3',5,5' -tetra-aldehyde biphenyl into 10ml of mixed organic solvent of tetrahydrofuran and DMAc (wherein the tetrahydrofuran and the DMAc are respectively 5ml), and stirring for 3min on a mechanical stirrer at 22 ℃ under the condition of controlling the rotating speed of a stirring rod to be 250 revolutions per minute to form a clear solution.

(2) Adding 0.31ml of polyhexamethylene biguanide hydrochloride and 0.31ml of PAAs into the clear solution, controlling the rotating speed in a magnetic stirrer at the temperature of 20 ℃ to 350 r/min, and stirring for 5min until the solution is uniformly stirred;

(3) adding 0.109ml of silane coupling agent octyl triethoxysilane into the obtained solution, and dispersing in an ultrasonic disperser at 20 ℃ for 10min to form a mixed solution;

(4) adding 1.08ml of a gel accelerator propylene oxide into the obtained solution, and carrying out ultrasonic treatment in an ultrasonic dispersion instrument at 25 ℃ for 10min to homogenize the solution to form precursor wet sol;

(5) adding the precursor wet sol obtained in the step (4) into a methanol solution containing 20ml, adding 0.59ml of organic ligands II, 4,4, 4-methylethyl tetraphenyl ammonium of COFs, stirring for 15min until the solution is white and milky, standing for 3min until the solution is stable, then locally heating for 3h by microwave to allow two organic ligands of COFs to be self-assembled to form Covalent Organic Frameworks (COFs), and converting the precursor wet sol into the COFs wet sol;

(6) loading Ag + in COFs wet sol by a post-synthesis modification method, putting the COFs wet sol solution into 50ml of methanol solution, adding 1.18g of AgNO3, carrying out ultrasonic treatment for 2min, then putting the COFs wet sol solution on a shaking table, vibrating for 20min, then putting the COFs wet sol solution into a microwave reactor, reacting for 45min, then heating in a water bath at 60 ℃ for 6h to fully complete the loading of Ag + on COFs, and generating guanidino/polyimide/Ag + -COFs wet sol;

(7) putting the guanidino/polyimide/Ag & lt + & gt-COFs wet sol obtained in the step (6) into a closed mold, and carrying out gel reaction in a drying oven at the temperature of 60 ℃ to form guanidino/polyimide/Ag & lt + & gt-COFs wet gel;

The multifunctional CoF aerogel containing guanidino/polyimide/Ag + obtained in the embodiment is subjected to an antibacterial test and a lasting antibacterial test, and the antibacterial rate of the prepared multifunctional COF aerogel containing guanidino/polyimide/Ag + is almost up to 100%, and the multifunctional COF aerogel containing guanidino/polyimide/Ag + and COFs is subjected to ultrasonic water washing, so that the antibacterial effect of the multifunctional COF aerogel is basically unchanged after the multifunctional COF aerogel is repeatedly used, the antibacterial effect and the antibacterial lasting property are greatly improved compared with those of a single-component antibacterial material, and the multifunctional COF aerogel containing guanidino/polyimide/Ag + is wide in application scene in the antibacterial field.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", and the like, refer to orientations or positional relationships that are based on the orientations or positional relationships shown in the drawings, or the orientations or positional relationships that the products of the present invention are conventionally placed in use, or the orientations or positional relationships that are conventionally understood by those skilled in the art, and are used for convenience in describing and simplifying the description, but do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Claims

1. The multifunctional degerming nanoporous COF aerogel is characterized by comprising porous COFs, wherein metal ions, guanidyl and polyimide are arranged on the porous COFs, and the metal ions are Ag +.

2. A preparation method of a multifunctional degerming nanopore COF aerogel is characterized by comprising the following steps:

s1, placing organic ligands I of COFs in an organic solvent, stirring for 3-5 min on a mechanical stirrer at 18-25 ℃ with the rotating speed of a stirring rod controlled to be 250-350 r/min, and preparing an organic ligand I-organic solvent solution;

s2, adding guanidyl polymer and polyimide precursor polyamide acid into the organic ligand I-organic solvent solution system, and stirring for 3-5 min on a magnetic stirrer at the temperature of 20-25 ℃ and with the rotation speed controlled at 350-500 rpm;

3. The method for preparing multifunctional degerming nanopore COF aerogel according to claim 2, wherein the ratio of the organic ligand I to the organic solvent in the step S1 is 0.01-1: 1; the organic solvent in step S1 is: a mixed organic solvent of tetrahydrofuran and N, N-dimethylacetamide; the organic ligand I of the COFs is one of trimesic aldehyde, terephthalaldehyde, tetra (4-formylbenzene) methane, tetra-formyl phenyl porphyrin, 3',5,5' -tetra-formyl biphenyl, 1,2,4, 5-tetra (4-formylphenyl) benzene, 2 '-bipyridine-5, 5' -dicarboxaldehyde, 2, 5-dihydroxy terephthalic acid, 2, 5-dimethoxy benzene-1, 4-dicarboxaldehyde, 2, 6-naphthalene dicarboxaldehyde and 1,3, 5-tri (4-aminophenyl) benzene.

4. The method for preparing multifunctional degerming nanoporous COF aerogel according to claim 2, wherein the guanidino polymer and the polyimide precursor polyamic acid added in the step S2 are 0.1-10% of the organic ligand I-organic solvent solution system in terms of volume ratio.

5. The method for preparing multifunctional degerming nanoporous COF aerogel according to claim 2, wherein the silane coupling agent is added in the step S3 in an amount of 0.1-5% by volume of the stirred solution obtained in the step S2.

6. The method for preparing the multifunctional degerming nanoporous COF aerogel according to claim 2, wherein the silane coupling agent added in the step S3 is: propyl triethoxysilane, octyl trimethoxysilane, octyl triethoxysilane, dodecyl trimethoxysilane, dodecyl methyldimethoxysilane, and hexadecyl trimethoxysilane.

7. The method for preparing the multifunctional degerming nanopore COF aerogel according to claim 2, wherein in the step S4, the amount of the gel accelerator is controlled to be 10-40% of the mixed solution according to the volume ratio.

8. The method for preparing multifunctional degerming nanopore COF aerogel according to claim 2, wherein in step S5, the volume ratio of organic ligand i to organic ligand ii is 0.8-1.2: 1.

9. the method for preparing multifunctional degerming nanoporous COF aerogel according to claim 2, wherein the organic ligands II of COFs used in step S5 are: one of phenylenediamine, melem, 1,3, 5-triaminobenzene, biphenyldiamine, 5,15- (aminophenyl) -10, 20-phenylporphyrin, tetrakis (4-aminophenyl) methane, tris (4-aminophenyl) amine, 5 '-diamino-2, 2' -bipyridine, 2,4, 6-tris (4-aminophenoxy) -1,3, 5-triazine, 1,3, 5-tris (4-aminophenyl) benzene, 4, 4-methylenetetranilide, 2,3,5, 6-tetrafluoroterephthalic acid formaldehyde; the organic solvents used were: one of ethanol, methanol and dimethylformamide.

10. The method for preparing multifunctional degerming nanopore COF aerogel according to claim 2, wherein the step S6 of loading functional Ag + nano ions comprises the following specific steps: and (3) putting the prepared COFs wet sol into an organic solution containing Ag salt, carrying out ultrasonic treatment for 2-5 min, then oscillating the mixed solution on a shaking table for 15-25 min, then putting the mixed solution into a microwave reactor, controlling the microwave reaction rate, reacting for 45min, then heating in water bath at 45-60 ℃ for 6-12 h, and fully completing the loading of Ag & lt + & gt on the COFs to generate the guanidyl/polyimide/Ag & lt + & gt-COFs wet gel.