Polymerizable porous liquid for ammonia gas detection and preparation method and application thereof

Abstract

The invention relates to a polymerizable porous liquid for ammonia gas detection as well as a preparation method and application thereof, different polymerizable groups are introduced into a component A (namely a steric hindrance solvent component), so that the characteristics of a porous liquid coating are given, and the application field and range of the porous liquid are widened; moreover, the polymerizable porous liquid provided by the invention can be quickly converted into a faint yellow gel solid under subsequent ultraviolet irradiation, and a component B (namely a porous object component) in the material is anchored in the material, so that the problem of unstable sedimentation and dispersion of the porous object in the porous liquid under complex working conditions or long-term use is solved. Through the synergistic effect of the porous object (MOFs) and the polymerizable ionic liquid, stable and sensitive ammonia gas detection is realized, the limit of detection (LOD) can reach 0.120 ppm, stability is kept under continuous use of 14 cycles and 12000 s, and the method is suitable for ammonia gas detection of multiple scenes.

Description

Technical Field

[0001] This invention belongs to the field of ammonia detection and relates to a polymerizable porous liquid for ammonia detection, its preparation method, and its applications. Specifically, it relates to the research and development of a class of polymerizable porous liquids, and in particular, to optimizing the porous liquid formulation by adjusting the types and ratios of ionic liquids and porous guests. The goal is to improve the stability and sensitivity of polymerizable porous liquids for ammonia detection by designing the structures and formulations of the ionic liquids and porous guests, thereby enabling real-time, stable, and sensitive ammonia detection in multiple application scenarios. Background Art

[0002] Ammonia (NH3) is a colorless, pungent, and toxic gas commonly found in air, soil, and water. It is primarily produced by industrial emissions, fertilizer application, and animal manure. High concentrations of NH3 can pose significant risks to human health and the environment. NH3 can also be produced through human respiration. This is because human metabolism converts protein into urea, which accumulates and increases NH3 concentrations in the body, which is then exhaled. Therefore, the NH3 concentration in exhaled breath is also an indicator for analyzing human diseases. Therefore, accurate detection of NH3 concentration is crucial for human health, industrial production, and environmental protection.

[0003] The existing technologies have the following problems: (1) Requirement of high operating temperature: Traditional metal semiconductor materials such as SnO2, SnS2, MoSe2 and MoS2 require high energy for activation, so the required operating temperature is high; (2) High production cost: Some conductive two-dimensional materials and metal organic frameworks (MOFs) materials require specific ligands, the space available for structural design is limited and the cost is high; (3) Poor sensing stability: Some MOFs / ILs hybrid materials are unstable to use due to the liquid properties of the second component, and are difficult to meet actual application scenarios.

[0004] To address these issues, the present invention combines the advantages of MOFs and ionic liquids to design a polymerizable porous liquid for ammonia sensing. By introducing photosensitive groups into a hindered solvent (ionic liquid), the porous liquid is endowed with polymerizable properties, enabling it to rapidly polymerize into a gel-like solid under UV light. This overcomes the instability of conventional porous liquids and broadens their application areas, enabling them to be used as functional coatings for stable and sensitive NH3 sensing in flexible sensors, medical, and industrial environments. Summary of the Invention

[0005] Technical problems to be solved

[0006] To overcome the shortcomings of existing technologies, the present invention proposes a polymerizable porous liquid for ammonia detection, as well as its preparation method and application. The liquid comprises components A and B, which can be stored separately or mixed at room temperature, and a photosensitive initiator. This liquid maintains good fluidity at room temperature while maintaining a wide operating temperature range, photosensitivity, and ammonia detection performance, meeting the sensor requirements of miniaturization, flexibility, multifunctionality, stability, and ease of processing.

[0007] The present invention also aims to provide a polymerizable porous liquid for real-time detection of human motion and for use in a wearable flexible ammonia sensor. The liquid comprises components A and B, which can be stored separately or mixed at room temperature, and a photosensitive initiator. The liquid maintains good fluidity at room temperature while maintaining a wide operating temperature range, photosensitivity, and ammonia detection properties, meeting the sensor requirements of miniaturization, flexibility, multifunctionality, stability, and ease of processing.

[0008] Technical Solution

[0009] A polymerizable porous liquid for ammonia detection, characterized by comprising an ionic liquid component A and a porous guest component B, which can be stored separately or mixed at room temperature; the ionic liquid component A contains active groups that can be triggered by a photoinitiator in its structure; the active groups are any one or more of vinyl groups, acrylate groups, methacrylate groups, thiol groups, and epoxy groups; and the photoinitiator needs to be stored separately.

[0010] The weight ratio of the three substances, namely, the ionic liquid of component A, the porous guest of component B, and the photoinitiator, is component A: component B: photoinitiator = 100:2-20:0.5-3.

[0011] The active groups capable of being initiated by a photoinitiator are compounded with one or more ionic liquids to form an ionic liquid containing the above active groups; the ionic liquids containing the above active groups include 1-vinyl-3-heptyl imidazolium bromide, 1-vinyl-3-hexyl imidazolium bromide, 1-vinyl-3-hexenyl imidazolium bromide, 1-vinyl-3-heptyl imidazolium bis(trifluoromethanesulfonyl imide), 1-vinyl-3-hexyl imidazolium bis(trifluoromethanesulfonyl imide), 1-vinyl-3-epoxyimidazolium chloride, 1-allyl-3-hexyl imidazolium bromide, 1-allyl-3-hexenyl imidazolium bromide and 1-ethyl methacrylate-3-heptyl imidazolium bromide.

[0012] The B component porous guest is a metal organic framework MOFs or a product of functional modification of MOFs.

[0013] The MOFs functionalization modification is as follows: amino, carboxyl or sulfonic acid functional groups are grafted onto the surface of MOFs crystals to adjust the surface chemical properties; metal nanoparticles Ag, Au or Pt are loaded into the pores inside MOFs to achieve multi-level composite adsorption, catalytic and sensing activities; and a MOF-on-MOF heterostructure is obtained.

[0014] The MOFs are a combination of one or more of ZIF-8, ZIF-67 and UIO-6.

[0015] The photoinitiator is selected from TPO (diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide), 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone), 819 (phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide), I2959 (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone), 6976 (diphenyl [4- (phenylthio) phenyl] - hexafluoroantimonate sulfonium), HRcure-9387 bis (4-dodecylbenzene) iodonium hexafluoroantimonate or 820 (4,4-dimethyldiphenyl iodonium hexafluorophosphate).

[0016] A method for preparing the A component ionic liquid is characterized by the following steps: weighing, by mass fraction, 10 parts of an imidazole donor, 5 to 25 parts of an ion donor, 0.1 part of 2,6-di-tert-butyl-p-methylphenol and 100 parts of ethyl acetate, heating to 50 to 70° C. under magnetic stirring, nitrogen protection and condensation reflux, and then reacting for 24 hours; after the reaction is completed, standing and removing the supernatant, repeatedly washing with ethyl acetate, and vacuuming to obtain a self-made polymerizable ionic liquid, which is the A component.

[0017] A method for obtaining an ammonia-sensitive chemiresistive polymeric porous liquid sensor using a polymerizable porous liquid for ammonia detection, characterized by comprising the following steps:

[0018] 1. Weigh 100 parts of component A, 2-20 parts of component B, 0.5-2 parts of photosensitive initiator and 30 parts of ethanol, disperse them overnight under magnetic stirring, and then dry them in an oven at 65-90°C to obtain a polymerizable porous liquid.

[0019] 2. coating the porous liquid on the surface of the substrate or pouring it into a mold;

[0020] 3. Depending on the type of photosensitive initiator added, use ultraviolet light of the corresponding wavelength for 3-10 minutes to form a chemical resistance type polymeric porous liquid sensor with ammonia sensitivity.

[0021] An application of an ammonia-sensitive chemiresistive polymeric porous liquid sensor, characterized by being used for real-time, stable and sensitive detection of ammonia in multiple application scenarios.

[0022] Beneficial effects

[0023] The present invention proposes a polymerizable porous liquid for ammonia detection, a preparation method, and an application. By introducing different polymerizable groups into component A (i.e., the hindered solvent component), the porous liquid is given the characteristics of a coating, thereby broadening the application field and scope of the porous liquid. Moreover, the polymerizable porous liquid proposed in the present invention can be rapidly transformed into a pale yellow gel-like solid under subsequent ultraviolet light irradiation, anchoring component B (i.e., the porous guest component) in the material within the material, thereby solving the sedimentation and dispersion instability problems of the porous guest in the porous liquid under complex working conditions or long-term use.

[0024] The innovative features of the present invention are as follows:

[0025] 1. Active groups such as vinyl groups, acrylate groups, methacrylate groups, thiol groups, or epoxy groups that can be initiated by a photoinitiator are introduced into the hindered solvent of the porous liquid (component A of the present invention), enabling it to undergo a rapid and efficient polymerization reaction under ultraviolet light, innovatively solving the sedimentation and dispersion instability problems of the porous guest (component B of the present invention) in the porous liquid under complex working conditions or long-term use.

[0026] It should be noted that the ionic liquid having a photosensitive group or the compounding ratio of two or more ionic liquids selected in the present invention cannot be simply determined.

[0027] For example, when 1-vinyl-3-ethylimidazolium bromide is selected as component A, regardless of the selection or content of component B, the prepared polymerizable liquid cannot have a stable response to NH3, and a certain porosity cannot be observed in the liquid-derived membrane after polymerization.

[0028] For example, when 1-vinyl-3-hexyl imidazolium bromide and 1-vinyl-3-propylene imidazolium bromide are compounded as component A, the prepared polymerizable porous liquid and derived membrane have extremely poor film-forming properties and low porosity, and cannot be used for stable detection of NH3. In Example 3 of the present invention, 1-vinyl-3-hexyl imidazolium bromide and 1-vinyl-hexenimidazolium bromide are compounded as component A. The prepared polymerizable porous liquid and derived membrane have considerable mechanical properties (tensile strength 1.45 MPa, elongation at break 238%), and can maintain a rich multi-level pore structure within the material, with excellent NH3 sensing performance.

[0029] 2. By designing the ratio between components A and B and coordinating the components A and B, the multi-level pore structure in the material is maintained while ensuring the mechanical properties of the polymerizable porous liquid-derived membrane. Figure 3), therefore, the polymerizable porous liquid proposed in the present invention has excellent performance for NH3 detection.

[0030] It should be noted that the ratio between the A and B components determined by the present invention or the selection coordination of the A and B components are not simply able to be determined. If the B component composition is different, not only should the corresponding different A components be selected, the B component adding ratio should also be changed with the specific composition of the A component, otherwise it is not possible to NH3 with a stable response. For example, in the study, ZIF-67 is used as the B component, and 1-vinyl-3-epoxypropane imidazole chloride is used as the A component. The porosity of the prepared polymerizable porous liquid and the derived film is very low, which is relatively poor to detection performance. And the A component 1-vinyl-3-heptyl imidazole bromide selected in Example 4 can ensure the porosity of the polymerizable porous liquid and the derived film, has good NH3 detection performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 :Synthesis flow chart of polymerizable ionic liquids

[0032] Figure 2 :Photo of the actual polymerizable porous liquid

[0033] Figure 3 :Scanning electron microscopy (SEM) images of polymerizable porous liquid-derived membranes DETAILED DESCRIPTION

[0034] The present invention will now be further described with reference to the embodiments and accompanying drawings:

[0035] To achieve the purpose of the present invention, the following technical solution is adopted, including component A and component B that can be stored separately or mixed, and a photoinitiator that needs to be stored separately, wherein the weight ratio of component A: component B: photosensitive additive = 100:2~20:0.5~3.

[0036] Component A ionic liquid:

[0037] The A component ionic liquid structure has a vinyl group, an acrylate group, a methacrylate group, a thiol or an epoxy group, etc., which can be activated by a photoinitiator. Depending on the usage scenario, one or more ionic liquids can be used to compound as the A component of the polymerizable porous liquid. The ionic liquids containing the above groups are homemade by the laboratory, including but not limited to 1-vinyl-3-heptyl imidazolium bromide, 1-vinyl-3-hexyl imidazolium bromide, 1-vinyl-3-hexenyl imidazolium bromide, 1-vinyl-3-heptyl imidazolium bis(trifluoromethanesulfonyl imide), 1-vinyl-3-hexyl imidazolium bis(trifluoromethanesulfonyl imide), 1-vinyl-3-epoxyimidazolium chloride, 1-allyl-3-hexyl imidazolium bromide, 1-allyl-3-hexenyl imidazolium bromide and 1-ethyl methacrylate-3-heptyl imidazolium bromide. Preferably, the polymerizable porous liquid is composed of the following raw materials, calculated by mass fraction: 100 parts of 1-vinylimidazole hexylimidazole bromide and 10 parts of 1-vinyl-3 hexenylimidazole bromide.

[0038] B component porous guest:

[0039] The porous guest selected for component B is a combination of one or more of ZIF-8, ZIF-67 and UIO-66 in metal organic frameworks (MOFs). The ZIF-8 is characterized by being a zeolite imidazolate framework material with a chemical formula of Zn(C4H5N2)2, which is composed of Zn 2+ The metal center and 2-methylimidazole (2-MIM) organic ligand are self-assembled to form a hydrophobic microporous structure with adjustable pore size, where the micropore diameter is 0.34nm and the window aperture is It appears as a white powder under macroscopic conditions, and the single crystal particle size under microscopic conditions is 200-500nm. Preferably, the particle size of ZIF-8 is 300nm. The ZIF-67 is characterized in that it is a cobalt-based zeolite imidazolate skeleton material, and its chemical composition is Co(C4H5N2)2, which is composed of Co 2+ The topological crystal structure constructed by the metal center and the 2-MIM organic ligand through coordination bonds has the ability to form a three-dimensional through-microporous network with a pore size distribution of 0.35 to 1.05 nm. It appears as a purple powder under macroscopic conditions, and the single crystal particle size under microscopic conditions is 200 to 400 nm. The preferred ZIF-67 particle size is 280 nm. The UIO-66 is characterized by being a zirconium-based metal organic framework material characterized by its chemical composition of Zr6O4(OH)4(BDC)6 (BDC is a terephthalic acid ligand), having a cubic three-dimensional network topology structure, a pore size distribution of 0.8 to 1.2 nm, and the material is composed of Zr 4+The metal cluster and BDC ligands are formed through a twelve-linked pattern. The Zr6O4(OH)4 secondary structural unit and the ligands form eight tetrahedral microporous cages. Macroscopically, the product appears as a white powder, and microscopically, the individual crystals have a particle size of 400 to 1000 nm. The preferred particle size of UIO-66 is 600 nm.

[0040] The functional modification of the MOFs mentioned above includes the following methods:

[0041] Grafting amino, carboxyl or sulfonic acid functional groups on the surface of MOFs crystals to adjust the surface chemical properties;

[0042] Metal nanoparticles (Ag, Au, or Pt) are loaded into the pores of MOFs to achieve multi-level composite adsorption, catalytic, and sensing activities;

[0043] Together with MOFs, they form a MOF-on-MOF heterostructure.

[0044] Photoinitiator:

[0045] According to changes in usage scenarios and production conditions, the photoinitiator is selected from TPO (diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide), 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone), 819 (phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide), I2959 (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone), 6976 (diphenyl [4- (phenylthio) phenyl] - hexafluoroantimonate sulfonium), HRcure-9387 bis (4-dodecylbenzene) iodonium hexafluoroantimonate or 820 (4,4-dimethyldiphenyl iodonium hexafluorophosphate).

[0046] A method for preparing the polymerizable porous liquid for ammonia detection as described in any one of the above items comprises the following steps:

[0047] 1. Using 1-vinylimidazole, 1-allylimidazole, or imidazolium ethyl methacrylate as an imidazole donor and n-hexyl bromide, 6-bromo-1-hexene, epichlorohydrin, or n-heptane bromide as an ion donor, an ionic liquid with photosensitive polymerizable groups was prepared by quaternization of imidazole. The method comprises the following steps: weighing, by mass, 10 parts of the imidazole donor, 5-25 parts of the ion donor, 0.1 parts of 2,6-di-tert-butyl-p-methylphenol, and 100 parts of ethyl acetate; heating the mixture to 50-70°C under magnetic stirring, nitrogen protection, and reflux, followed by reaction for 24 hours. After the reaction is completed, the supernatant is removed and washed three times with ethyl acetate. The mixture is then vacuum-treated to obtain the self-prepared polymerizable ionic liquid, component A.

[0048] 2. Using metal salts such as zinc nitrate, zinc acetate, zinc sulfate, cobalt nitrate or cobalt chloride as metal precursors and 2-methylimidazole as organic ligand, different ZIF-8 or ZIF-67 were prepared. The process includes the following steps: weighing the metal precursor (10 parts) and the organic ligand (10 to 50 parts) by mass fraction, and dissolving the metal precursor and the organic ligand in 100 mL of water or methanol, respectively. Under rapid stirring, the organic ligand solution was quickly poured into the metal precursor solution, stirred for 1 minute, and then allowed to stand. In order to further control the particle size of MOFs, after standing for 3 to 24 hours, the product was collected by centrifugation, washed three times with methanol, and dried in an oven at 70°C overnight to obtain MOFs powder.

[0049] UIO-66 of varying particle sizes was prepared using zirconium chloride or zirconium nitrate as a metal precursor, terephthalic acid, 2-aminoterephthalic acid, or 2-sulfonatoterephthalic acid as an organic ligand, and acetic acid or formic acid as a modifier. The process involved weighing, by mass, 10 parts of the metal precursor, 8-50 parts of the organic ligand, 10 parts of the modifier, 100 parts of DMF, and 20 parts of water. The reaction was hydrothermally reacted at 120-150°C for 16-24 hours, followed by centrifugation and multiple washings with DMF and methanol. The resulting powder was then oven-dried at 70°C overnight to yield a white UIO-66 powder.

[0050] 3. Weigh component A (100 parts), component B (2-20 parts), photosensitive initiator (0.5-2 parts) and ethanol (30 parts), disperse them overnight under magnetic stirring, and then dry them in an oven at 70°C to obtain a polymerizable porous liquid.

[0051] A method for using any of the above-mentioned polymerizable porous liquids for ammonia detection comprises the following steps:

[0052] 1. Weigh component A (100 parts), component B (2-20 parts), photosensitive initiator (0.5-2 parts) and ethanol (30 parts), disperse them overnight under magnetic stirring, and then dry them in an oven at 70°C to obtain a polymerizable porous liquid.

[0053] 2. coating the porous liquid on the surface of the substrate manually or mechanically or pouring it into a specific mold;

[0054] 3. Depending on the type of photosensitive initiator added, use ultraviolet light of the corresponding wavelength for 5 minutes to form a chemical resistance type polymeric porous liquid sensor with ammonia sensitivity. Specific embodiment:

[0056] The invention is described in further detail below so that those skilled in the art can implement it with reference to the description.

[0057] It should be understood that terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or other elements or combinations thereof.

[0058] Example 1

[0059] A method for preparing a polymerizable porous liquid for ammonia detection comprises the following steps:

[0060] a. Weigh 1-vinylimidazole (10 parts), n-heptane bromide (5 parts), 2,6-di-tert-butyl-p-methylphenol (0.1 parts), and ethyl acetate (100 parts) in the following weight fractions, raise the temperature to 70°C under magnetic stirring, nitrogen protection, and condensation reflux, and react for 24 hours.

[0061] b. After the reaction is completed, the mixture is allowed to stand and the supernatant is taken out. The mixture is washed three times with ethyl acetate and vacuum dried to remove the precipitant to obtain a light yellow polymerizable ionic liquid, thereby obtaining component A.

[0062] c. Weigh zinc nitrate (10 parts) and 2-methylimidazole (20 parts) in the following weight fractions, and dissolve each zinc nitrate and 2-methylimidazole in 100 mL of methanol. Pour the 2-methylimidazole methanol solution into the zinc nitrate methanol solution rapidly under rapid stirring, stir for 1 minute to uniformly disperse, let stand for 8 hours, collect the product by centrifugation, wash three times with methanol, and dry in an oven at 70°C overnight to obtain component B.

[0063] d. The prepared component A, component B, and photoinitiator were stored separately according to a weight ratio of component A: component B: I2959 = 100:10:1 to obtain the polymerizable porous liquid for ammonia detection.

[0064] A method for using any of the above-mentioned polymerizable porous liquids for ammonia detection comprises the following steps:

[0065] 1. According to the weight ratio, weigh component A (100 parts), component B (10 parts), I2959 (1 part) and ethanol (30 parts), disperse them under magnetic stirring overnight, and then dry them in an oven at 70°C to obtain a polymerizable porous liquid.

[0066] 2. coating the porous liquid on the surface of the substrate manually or mechanically or pouring it into a specific mold;

[0067] 3. Irradiate the sample with 365 nm ultraviolet light for 5 min to form a chemical resistance polymeric porous liquid sensor with ammonia sensitivity.

[0068] Example 2

[0069] A method for preparing a polymerizable porous liquid for ammonia detection comprises the following steps:

[0070] a. Weigh 1-vinylimidazole (10 parts), epichlorohydrin (10 parts), 2,6-di-tert-butyl-p-methylphenol (0.1 parts), and ethyl acetate (100 parts) in the following weight fractions, raise the temperature to 60°C under magnetic stirring, nitrogen protection, and condensation reflux, and react for 24 hours.

[0071] b. After the reaction is completed, the mixture is allowed to stand and the supernatant is removed. The mixture is washed three times with ethyl acetate and vacuum dried to remove the precipitant to obtain a light yellow polymerizable ionic liquid 1-vinyl-3-epoxypropylene chloride to prepare component A.

[0072] c. Weigh zinc nitrate (10 parts) and 2-methylimidazole (20 parts) in the following weight fractions, and dissolve each zinc nitrate and 2-methylimidazole in 100 mL of methanol. Pour the 2-methylimidazole methanol solution into the zinc nitrate methanol solution rapidly under rapid stirring, stir for 1 minute to uniformly disperse, let stand for 8 hours, collect the product by centrifugation, wash three times with methanol, and dry in an oven at 70°C overnight to obtain component B.

[0073] d. The prepared component A, component B, and photoinitiator were stored separately according to a weight ratio of component A: component B: HRcure-9387 = 100:10:2 to obtain the polymerizable porous liquid for ammonia detection.

[0074] A method for using any of the above-mentioned polymerizable porous liquids for ammonia detection comprises the following steps:

[0075] 1. According to the weight ratio, weigh component A (100 parts), component B (10 parts), photosensitive initiator (2 parts) and ethanol (30 parts), disperse them under magnetic stirring overnight, and then dry them in an oven at 70°C to obtain a polymerizable porous liquid.

[0076] 2. coating the porous liquid on the surface of the substrate manually or mechanically or pouring it into a specific mold;

[0077] 3. Use 250-260nm wavelength ultraviolet light irradiation for 5 minutes to form a chemical resistance type polymer porous liquid sensor with ammonia sensitivity.

[0078] Example 3

[0079] A method for preparing a polymerizable porous liquid for ammonia and strain detection comprises the following steps:

[0080] a. Weigh 1-vinylimidazole (10 parts), n-hexyl bromide (5 parts), 2,6-di-tert-butyl-p-methylphenol (0.1 parts), and ethyl acetate (100 parts) in the following weight fractions, raise the temperature to 70°C under magnetic stirring, nitrogen protection, and condensation reflux, and react for 24 hours.

[0081] b. After the reaction is completed, the mixture is allowed to stand and the supernatant is removed. The mixture is washed three times with ethyl acetate and vacuum dried to remove the precipitant to obtain a light yellow polymerizable ionic liquid 1-vinyl-3-hexyl imidazolium bromide.

[0082] c. Weigh 1-vinylimidazole (10 parts), 6-bromo-1-hexene (6 parts), 2,6-di-tert-butyl-p-methylphenol (0.1 parts) and ethyl acetate (100 parts) in the following weight fractions, raise the temperature to 70°C under magnetic stirring, nitrogen protection and condensation reflux, and react for 24 hours.

[0083] d. After the reaction is completed, the mixture is allowed to stand and the supernatant is removed. The mixture is washed three times with ethyl acetate and vacuum dried to remove the precipitant to obtain a reddish-brown polymerizable ionic liquid 1-vinyl-3-hexenyl imidazole bromide.

[0084] e. Weigh 10 parts of the ionic liquid in b and 1 part of the ionic liquid in d, and mechanically stir until a uniform yellow colloid is obtained to prepare component A;

[0085] f. Weigh zinc nitrate (10 parts) and 2-methylimidazole (20 parts) in the following weight fractions, and dissolve each zinc nitrate and 2-methylimidazole in 100 mL of methanol. Pour the 2-methylimidazole methanol solution into the zinc nitrate methanol solution rapidly under rapid stirring, stir for 1 minute to uniformly disperse the mixture, let it stand for 8 hours, collect the product by centrifugation, wash it three times with methanol, and dry it in an oven at 70°C overnight to obtain component B.

[0086] g. The prepared component A, component B, and photoinitiator were stored separately according to a weight ratio of component A: component B: I2959 = 100:10:1 to obtain the polymerizable porous liquid for ammonia and strain detection.

[0087] A method for using any of the above-mentioned polymerizable porous liquids for ammonia detection comprises the following steps:

[0088] 1. According to the weight ratio, weigh component A (100 parts), component B (10 parts), I2959 (1 part) and ethanol (30 parts), disperse them under magnetic stirring overnight, and then dry them in an oven at 70°C to obtain a polymerizable porous liquid.

[0089] 2. coating the porous liquid on the surface of the substrate manually or mechanically or pouring it into a specific mold;

[0090] 3. Irradiate the surface of the sample with 365 nm ultraviolet light for 5 min to form a chemical resistance polymeric porous liquid sensor with ammonia and strain sensitivity.

[0091] Example 4

[0092] A method for preparing a porous liquid for ammonia and strain detection comprises the following steps:

[0093] a. Weigh 1-vinylimidazole (10 parts), n-heptane bromide (5 parts), 2,6-di-tert-butyl-p-methylphenol (0.1 parts), and ethyl acetate (100 parts) in the following weight fractions, raise the temperature to 70°C under magnetic stirring, nitrogen protection, and condensation reflux, and react for 24 hours.

[0094] b. After the reaction is completed, the mixture is allowed to stand and the supernatant is removed. The mixture is washed three times with ethyl acetate and vacuum dried to remove the precipitant to obtain a light yellow polymerizable ionic liquid 1-vinyl-3-heptyl imidazolium bromide to prepare component A.

[0095] c. Weigh cobalt nitrate (10 parts) and 2-methylimidazole (20 parts) in the following weight fractions, and dissolve each in 100 mL of methanol. Pour the methanol solution of 2-methylimidazole into the methanol solution of cobalt nitrate rapidly under rapid stirring, stir for 1 minute to uniformly disperse the mixture, let it stand for 8 hours, collect the product by centrifugation, wash it three times with methanol, and dry it in an oven at 70°C overnight to obtain component B.

[0096] d. The prepared component A, component B, and photoinitiator were stored separately according to a weight ratio of component A: component B: I2959 = 100:10:1 to obtain the polymerizable porous liquid for ammonia detection.

[0097] A method for using any of the above-mentioned polymerizable porous liquids for ammonia detection comprises the following steps:

[0098] 1. According to the weight ratio, weigh component A (100 parts), component B (10 parts), I2959 (1 part) and ethanol (30 parts), disperse them under magnetic stirring overnight, and then dry them in an oven at 70°C to obtain a polymerizable porous liquid.

[0099] 2. coating the porous liquid on the surface of the substrate manually or mechanically or pouring it into a specific mold;

[0100] 3. Use 365nm wavelength ultraviolet light irradiation for 5 minutes to form a chemical resistance type polymeric porous liquid sensor with NH3 sensitivity.

[0101] The polymerizable porous liquid for ammonia and strain detection and its preparation method disclosed in the present invention achieve stable and sensitive ammonia detection through the synergistic effect of porous guests (MOFs) and polymerizable ionic liquids. Its detection limit (LOD) can reach 0.120ppm and remains stable under 14 cycles and 12,000s of continuous use, making it suitable for ammonia detection in multiple scenarios.

Claims

1. A polymerizable porous liquid for ammonia detection, characterized in that The invention comprises an ionic liquid component A and a porous guest component B, which can be stored separately or mixed at room temperature; the ionic liquid component A contains active groups that can be triggered by a photoinitiator in its structure; the active groups are any one or more of vinyl groups, acrylate groups, methacrylate groups, thiol groups, and epoxy groups; and the photoinitiator needs to be stored separately.

2. The polymerizable porous liquid for ammonia detection according to claim 1, characterized in that: The weight ratio of the three substances, namely, the ionic liquid of component A, the porous guest of component B, and the photoinitiator, is component A: component B: photoinitiator = 100:2-20:0.5-3.

3. The polymerizable porous liquid for ammonia detection according to claim 1, characterized in that: The active groups capable of being initiated by a photoinitiator are compounded with one or more ionic liquids to form an ionic liquid containing the above active groups; the ionic liquids containing the above active groups include 1-vinyl-3-heptyl imidazolium bromide, 1-vinyl-3-hexyl imidazolium bromide, 1-vinyl-3-hexenyl imidazolium bromide, 1-vinyl-3-heptyl imidazolium bis(trifluoromethanesulfonyl imide), 1-vinyl-3-hexyl imidazolium bis(trifluoromethanesulfonyl imide), 1-vinyl-3-epoxyimidazolium chloride, 1-allyl-3-hexyl imidazolium bromide, 1-allyl-3-hexenyl imidazolium bromide and 1-ethyl methacrylate-3-heptyl imidazolium bromide.

4. The polymerizable porous liquid for ammonia detection according to claim 1, characterized in that: The B component porous guest is a metal organic framework MOFs or a product of functional modification of MOFs.

5. The polymerizable porous liquid for ammonia detection according to claim 1, characterized in that: The MOFs functionalization modification is as follows: amino, carboxyl or sulfonic acid functional groups are grafted onto the surface of MOFs crystals to adjust the surface chemical properties; metal nanoparticles Ag, Au or Pt are loaded into the pores inside MOFs to achieve multi-level composite adsorption, catalytic and sensing activities; and a MOF-on-MOF heterostructure is obtained.

6. The polymerizable porous liquid for ammonia detection according to claim 4 or 5, characterized in that: The MOFs are a combination of one or more of ZIF-8, ZIF-67 and UIO-6.

7. The polymerizable porous liquid for ammonia detection according to claim 1, characterized in that: The photoinitiator is selected from TPO (diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide), 1173 (2-hydroxy-2-methyl-1-phenyl-1-propanone), 819 (phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide), I2959 (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone), 6976 (diphenyl [4- (phenylthio) phenyl] - hexafluoroantimonate sulfonium), HRcure-9387 bis (4-dodecylbenzene) iodonium hexafluoroantimonate or 820 (4,4-dimethyldiphenyl iodonium hexafluorophosphate).

8. A method for preparing the ionic liquid of component A according to any one of claims 1 to 4, characterized in that The steps are as follows: 10 parts of an imidazole donor, 5 to 25 parts of an ion donor, 0.1 part of 2,6-di-tert-butyl-p-methylphenol and 100 parts of ethyl acetate are weighed in mass fraction, the temperature is raised to 50 to 70° C. under magnetic stirring, nitrogen protection and condensation reflux, and then the reaction is carried out for 24 hours; after the reaction is completed, the supernatant is allowed to stand and the supernatant is removed, repeatedly washed with ethyl acetate, and vacuumed to obtain a self-made polymerizable ionic liquid, which is component A.

9. A method for obtaining an ammonia-sensitive chemiresistive polymeric porous liquid sensor using the polymerizable porous liquid for ammonia detection according to any one of claims 1 to 8, characterized in that The following steps are involved:

1. Weigh 100 parts of component A, 2-20 parts of component B, 0.5-2 parts of photosensitive initiator and 30 parts of ethanol, disperse them overnight under magnetic stirring, and then dry them in an oven at 65-90°C to obtain a polymerizable porous liquid.

2. coating the porous liquid on the surface of the substrate or pouring it into a mold; 3. Depending on the type of photosensitive initiator added, use ultraviolet light of the corresponding wavelength for 3-10 minutes to form a chemical resistance type polymeric porous liquid sensor with ammonia sensitivity.

10. Application of an ammonia-sensitive chemiresistive polymeric porous liquid sensor, characterized by: Real-time, stable, and sensitive detection of ammonia for multiple applications.

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