Silver-pi conductive polymer gel material, preparation method thereof and application of silver-pi conductive polymer gel material in hydrazine vapor sensing

Abstract

The invention discloses a silver-pi conductive polymer gel material, a preparation method thereof and application of the silver-pi conductive polymer gel material in hydrazine vapor sensing. The material is constructed by precise self-assembly of A, A '-bispyridine hydrazone functionalized column [5] arene macrocycles and silver (I) ions through coordination driving. Through Ag-N coordination, Ag.... pi interaction and multiple C-H.... pi / pi.... pi accumulation, a gel network with an extended conjugated system and conductivity is constructed. Based on a'multi-site cooperation-enhanced capture and recognition 'strategy, the gel material can realize high-selectivity and high-sensitivity detection on hydrazine steam through three signal channels of electrochemistry, colorimetry and fluorescence, and the electrochemical detection limit is as low as 5 ppb. The method has a wide application prospect in the field of toxic pollutant gas sensing and monitoring.

Description

Technical Field

[0001] This invention belongs to the fields of supramolecular chemistry, functional materials and sensing technology. Specifically, it relates to a silver-π conductive polymer gel material and its preparation method based on the self-assembly of A,A'-bispyridinehydrazone functionalized conjugated column[5] aromatic macrocyclic molecules and silver (I). It also relates to the application of this silver-π conductive polymer gel material in high-efficiency hydrazine vapor sensing. Background Technology

[0002] Hydrazine, an important chemical and pharmaceutical raw material, is widely used in drug synthesis, satellite / rocket fuel, nuclear power corrosion protection, and fine chemicals. However, hydrazine vapor is highly irritating and corrosive, and is acutely toxic, posing a serious potential threat to human health. Inhalation of low concentrations of hydrazine vapor can cause dizziness, shortness of breath, and coma. Long-term exposure to high concentrations of hydrazine vapor can lead to pulmonary edema, irreversible damage to the central nervous system, and harm to the liver and kidneys.

[0003] Current instrumental methods for detecting hydrazine vapor suffer from drawbacks such as high cost, inconvenience in on-site testing, and slow response speed, failing to meet the demands for rapid and accurate monitoring in real-world scenarios. Therefore, designing and developing ultrasensitive stimulus-response sensing materials for hydrazine vapor has significant practical application value and market demand.

[0004] With the rapid development of macrocyclic chemistry and supramolecular chemistry, the rational design and assembly of macrocycles are playing an increasingly crucial role in the preparation of stimulus-responsive supramolecular polymer materials. Among the macrocycles reported so far, columnar [n]arenes, first reported by Ogoshi, have shown outstanding application value in supramolecular self-assembly, host-guest recognition, ultrasensitive detection, catalysis, and adsorption separation due to their ability to provide a variety of supramolecular interactions and their adaptive cavity structure. Therefore, the rationally designed columnar [5]arene macrocycle assembly strategy and the targeted host-guest recognition of the target guest provide broad opportunities for the design of advanced stimulus-responsive supramolecular polymer materials. However, reports on the design of stimulus-responsive supramolecular polymer-based conductive functional materials using columnar [5]arene macrocycle self-assembly strategies are still very rare, and the assembly and construction of stimulus-responsive functional supramolecular polymers using cation-π interactions remains a challenging topic. Therefore, how to rationally utilize various supramolecular interactions such as the cation-π interaction of columnar aromatic hydrocarbons[5] to accurately assemble and construct stimulus-responsive supramolecular polymer conductive materials provides a new opportunity for developing macrocyclic assembled supramolecular conductive gel materials for sensing specific toxic gases (such as hydrazine vapor).

[0005] This invention provides a novel silver-π conductive polymer gel, Ag-π-CPG, constructed by coordination-driven precise self-assembly of bispyridine hydrazone-functionalized conjugated column[5] aromatics and silver (I) ions, which can be used for efficient sensing of hydrazine vapor. First, in order to achieve the conductive properties of the stimulus-responsive supramolecular polymer material, we rationally introduce Ag into the bispyridine hydrazone-functionalized conjugated column[5] aromatics pre-assembly process. + First, by leveraging the coordination-driven role of multiple sites, the assembly of Ag-π supramolecular polymers can be precisely regulated to construct conductive Ag-π polymer gels. Second, the pre-embedded multiple sites endow the Ag-π supramolecular polymer conductive gel with multi-stimulus responsiveness. Using Ag⁺ sites as decoys and columnar aromatic macrocycles as carriers for synergistic-enhanced capture and recognition, this facilitates highly selective and sensitive detection of hydrazine vapor. Based on the "multi-site synergistic-enhanced capture and recognition" strategy, the silver-π conductive polymer gel Ag-π-CPG can achieve highly sensitive detection of hydrazine vapor through electrochemical, colorimetric, and fluorescence signal channels. Summary of the Invention

[0006] The purpose of this invention is to provide a silver-π conductive polymer gel material with stable structure and excellent conductivity, and a method for preparing the same. Another objective of this invention is to provide the application of this silver-π conductive polymer gel material in high-efficiency hydrazine vapor sensing, thereby solving the problems of low sensitivity, poor specificity, and inconvenient detection in existing hydrazine vapor detection methods.

[0007] I. Silver-π Conductive Polymer Gel Materials and Their Preparation Methods The silver-π conductive polymer gel material of the present invention is constructed by precise self-assembly of A,A'-bispyridinehydrazone-functionalized conjugated columnar aromatic hydrocarbon (PYP5) and silver (I) ions through coordination-driven process, and its structural formula is as follows: .

[0008] The structural formula of A,A'-bispyridinehydrazone-functionalized conjugated columnar aromatic hydrocarbon (PYP5) is as follows: .

[0009] The synthesis of A,A'-bispyridinehydrazone-functionalized conjugated columnar aromatic hydrocarbons [5] (PYP5) was described in references J. Tian, ​​X.Han, H.-R. Yang, J. Liu, J.-F. Chen, T.-B. Wei, H. Yao, W.-J. Qu, B. Shi, Q.Lin, Nat. Commun. 2025, 16 , 6481. The preparation method of the silver-π conductive polymer gel material of the present invention is to add the A,A'-bispyridinehydrazone functionalized conjugated columnar aromatic host molecule PYP5 to a mixture of DMSO and H2O, then add silver salt, heat until completely dissolved, then let it stand and cool to room temperature to obtain a light yellow silver-π conductive polymer gel Ag-π-CPG ( Figure 1 ).

[0010] Among them, the molar ratio of A,A'-bispyridinehydrazone-functionalized conjugated column[5] aromatics to silver salt is 1:2-1:3; in the mixture of DMSO and H2O, the volume content of H2O is 15%~25%.

[0011] II. Self-assembly mechanism and structural characteristics of silver-π conductive polymer gel materials The assembly structure of the silver-π conductive polymer gel Ag-π-CPG was confirmed by X-ray single-crystal diffraction, and the crystal structure showed that ( Figure 2 ), Ag + The coordination structure involves simultaneous coordination with both the pyridine nitrogen atom and the imine nitrogen atom on the bispyridine hydrazone arm of PYP5 via Ag-N bonds. + Under the regulation of ions, one-dimensional chain-like Ag–π supramolecular polymers are further assembled through adjacent Ag···π interactions (distances of 2.863 Å and 2.962 Å, respectively). Figure 3 Furthermore, the multiple C–H···π and π···π interactions between one-dimensional chain-like Ag-π supramolecular polymers effectively extend the conjugated system. Figure 4 This gives the material a charge transport capability similar to that of a wire. Simultaneously, the metal coordination of the Ag⁺ sites and Ag···π interactions within the assembly, in conjunction with the guest recognition sites of the pyridine hydrazone-functionalized columnar aromatic macrocycle, construct a unique assembly structure. Figure 3-6 Together, they construct a microenvironment inside and outside the macrocyclic cavity that "multi-site synergy enhances capture and recognition," providing an ideal interface for the precise capture of hydrazine molecules. The free volume (FV) calculated based on single-crystal data is 1918.495 ų, and the free volume fraction (FVF) is as high as 46.52%. Figure 7 This provides ample space for the capture and recognition of hydrazine molecules.

[0012] 1 1H NMR titration experiments further confirmed the precise self-assembly mechanism. First, Ag was subjected to titration at room temperature. + Between the PYP5 rings 1 H NMR titration experiment ( Figure 8 With different equivalents of Ag +When added to a constant concentration of PYP5 solution, the signal peaks of protons Hd, He, and Hf on the conjugated bispyridine hydrazone arms shifted to a higher field, while the signal peaks of protons Ha, Hb, and Hc showed a significant lower field shift. This can be attributed to the metal coordination between Ag⁺ and the pyridine nitrogen atoms and imine nitrogen atoms on the PYP5 bispyridine hydrazone arms, and also indicates the presence of Ag···π interactions in the assembly. Simultaneously, the signal peaks of protons Hj, Hk, and Hm on PYP5 showed a significant higher field shift, indicating the formation of abundant CH···π interactions in the assembly. Proton HCl also showed a significant chemical shift change, which can be attributed to Ag···π interactions, π···π stacking, and CH···π interactions in the assembly.

[0013] III. Application of Silver-π Conductive Polymer Gel Materials in High-Efficiency Hydrazine Vapor Sensing The silver-π conductive polymer gel material of this invention is based on a "multi-site synergistic-enhanced capture and recognition" strategy, which can achieve highly sensitive and specific detection of hydrazine vapor through three signal channels: electrochemical, colorimetric, and fluorescence. Specific application performance is as follows: 1. Colorimetric and fluorescence sensing performance: (1) Selectivity: To evaluate the selectivity and stimulus-response behavior of Ag-π-CPG to common toxic vapors in the laboratory, a vapor exposure experiment was conducted. The results showed that only hydrazine vapor elicited a significant stimulus-response behavior in Ag–π-CPG. Figure 9 Ag–π-CPG is pale yellow under natural light, with a smooth surface, and exhibits blue fluorescence under 365 nm ultraviolet light. Upon exposure to hydrazine vapor, the Ag–π-CPG surface rapidly changes from pale yellow to black, accompanied by complete fluorescence quenching. These phenomena indicate that Ag–π-CPG can respond rapidly to hydrazine vapor through obvious color and fluorescence changes. However, it shows no obvious color or fluorescence changes to common toxic vapors such as ammonia, formaldehyde, acetaldehyde, benzene, pyridine, toluene, diethyl ether, and 1,2-dichloroethane, indicating its excellent specific recognition ability for hydrazine vapor. Figure 9 ).

[0014] (2) Sensitivity: By naked-eye colorimetric detection, the detection limit (LOD) of Ag-π-CPG for hydrazine vapor is as low as 0.1 ppm. Figure 10 The concentration of hydrazine vapor is far below the permissible exposure limit for hydrazine set by the U.S. Occupational Safety and Health Administration (OSHA), which meets the need for rapid screening of low-concentration hydrazine vapor.

[0015] 2. Sensing performance of Ag-π-CPG for hydrazine vapor in electrochemical mode (1) Electrode Design: Considering that metal gel materials usually inherit the conductive properties of metals, the detection performance of Ag-π-CPG for hydrazine vapor was further evaluated from an electrochemical perspective. To verify the feasibility of Ag-π-CPG as a conductive material, a compact electrode was designed and fabricated using 3D printing technology. Figure 11 Ag-π-CPG metal gel is filled between two pre-embedded platinum sheets at the electrode end to create a conductive path. This ingenious structural design allows only 1 µL of gel to be used per test, significantly reducing sample consumption and facilitating rapid on-site detection.

[0016] (2) Selectivity: To evaluate the electrochemical response of Ag-π-CPG to various organic vapors, its conductivity was measured at a vapor concentration of 10 ppb using a source meter combined with a compact electrode. At a vapor concentration of 10 ppb, only hydrazine vapor caused a significant change in the relative conductivity (Δσ / σ0) of Ag–π-CPG, while other toxic vapors showed no obvious response. Figure 12 This demonstrates that it possesses a highly selective electrochemical recognition capability.

[0017] (3) Sensitivity: The conductivity changes of Ag-π-CPG before and after exposure to different concentrations of hydrazine vapor were monitored by electrochemical testing. Electrochemical testing showed that ( Figure 13-14 At a concentration of 1 ppb hydrazine vapor, the conductivity of Ag-π-CPG remained essentially unchanged; at concentrations as low as 5 ppb, the conductivity began to decrease, with a relative change rate of 7.1%; at concentrations of 10 ppm and 100 ppm, the conductivity decreased significantly, and the relative change rate tended to stabilize. These results demonstrate that the electrochemical detection limit of Ag-π-CPG is as low as 5 ppb, and its sensitivity far exceeds that of existing conventional detection materials, enabling ultrasensitive detection of hydrazine vapor.

[0018] 3. Analysis of the response mechanism of highly sensitive stimuli To investigate the highly sensitive stimulus response mechanism of Ag-π-CPG to hydrazine vapor, we first conducted a reaction between Ag-π-CPG and hydrazine molecules. 1 H NMR titration experiment ( Figure 8 When hydrazine molecules are added to Ag–π-CPG solution, the proton signal peaks Ha, Hb, and Hc on the PYP5 bispyridine hydrazone arm exhibit significant high-field chemical shifts, while the proton signal peaks Hd, He, and Hf exhibit significant low-field chemical shifts. This indicates that hydrazine molecules can induce a significant high-field chemical shift in the Ag–π-CPG assembly of Ag. +Site reduction disrupts the coordination between Ag⁺ and PYP5, as well as the Ag···π interaction. Simultaneously, the signal peaks of protons Hg and Hi on the functional arms shift to higher fields, while the signal peak of proton Hh shifts to lower fields; the signal peaks of protons Hm, Hj, and Hk on the columnar aromatic ring cavity shift to lower fields, while the signal peak of proton Hl shifts to higher fields. These results indicate that the columnar aromatic ring macrocycle can capture and enrich hydrazine molecules in and around the macrocycle cavity through a "multi-site synergistic-enhanced capture and recognition" microenvironment. This process leads to the collapse of the structural integrity of Ag-π-CPG, a rapid decrease in conductivity, and rapid fluorescence quenching. Furthermore, the reduction of Ag⁺ by hydrazine molecules changes the color of Ag-π-CPG from pale yellow to black, and the smooth surface collapses. Subsequently, high-resolution mass spectrometry (HR-MS) was used to characterize Ag-π-CPG in response to hydrazine vapor. The results showed that no Ag was found after responding to hydrazine vapor. + The coordination structure signal peaks corresponding to PYP5 prove that Ag + The coordination structure with PYP5 and the Ag···π interactions within the assembly are disrupted. Interestingly, in the HR-MS spectrum, the signal peaks at 1193.6089 and 1359.6554 are related to [PYP5 + H]. + and [PYP5 + 4N2H4 + K] + The theoretical value is very close ( Figure 15 and Figure 16 This indicates that the PYP5 macrocycle can form a host-guest complex with a binding stoichiometric ratio of 1:4 with hydrazine molecules through a "multi-site synergistic-enhanced capture and recognition" strategy. These results demonstrate that the "multi-site synergistic-enhanced capture and recognition" microenvironment constructed based on the conjugated columnar aromatic macrocycle functions simultaneously inside and outside the cavity, exhibiting a highly sensitive response to hydrazine molecules and causing them to accumulate densely in and around the macrocycle cavity.

[0019] Subsequently, the chemical states of silver and nitrogen in Ag-π-CPG before and after the response to hydrazine vapor were examined by X-ray photoelectron spectroscopy (XPS). Figure 17 Experimental results show that, in response to hydrazine vapor, the Ag3d peak shifted to a lower binding energy by 0.34 eV, indicating a decrease in the Ag coordination number. + The structure was reduced. Simultaneously, the N1s peak shifted by 1.24 eV to a higher binding energy after responding to hydrazine vapor, proving that the original Ag-N coordination bond had been broken by hydrazine vapor. Furthermore, scanning electron microscopy (SEM) microstructure characterization experiments also provided evidence for the structural changes in the assembly. Figure 18 As shown, when Ag-π-CPG is exposed to hydrazine vapor, its smooth nanosphere structure is disrupted, transforming into a bulky, aggregated nanosphere structure. This morphological change indicates that Ag... +The coordination connection between the pyridine nitrogen atom and the imine nitrogen atom on PYP5 is disrupted, and the structural integrity of the assembly is compromised.

[0020] The above experimental results fully reveal the highly sensitive sensing mechanism of Ag-π-CPG for hydrazine vapor. The Ag pre-embedded in the Ag-π-CPG assembly... + The microenvironment inside and outside the macrocyclic cavity, constructed by the site and the macrocyclic guest recognition site of the columnar aromatic hydrocarbon, provides an ideal platform for highly sensitive sensing of hydrazine molecules. When hydrazine molecules approach Ag-π-CPG, the columnar aromatic hydrocarbon macrocycle fully utilizes its multi-site synergistic-enhanced capture and recognition function, causing hydrazine molecules to be tightly enriched in and around the macrocyclic cavity. Simultaneously, the hydrazine molecules attract Ag... + The reduction at the sites significantly reduced the number of Ag⁺ charge carriers in the assembly, leading to the depolymerization of the coordination assembly structure and the destruction of the conductive network structure. SEM showed that Ag⁺… + After site reduction, the resulting silver particles aggregate and disperse as isolated islands within the collapsed gel network. Figure 18 (b) This causes cracks in the original uniform network, preventing the formation of an electron permeation network, thus affecting charge transport paths and blocking conductive pathways. This results in a rapid decrease in the conductivity of Ag-π-CPG, enabling ultrasensitive detection of hydrazine vapor. Simultaneously, this is accompanied by a change in the color state of the conductive gel and rapid fluorescence quenching. These results provide strong support for our proposed novel strategy of using a "multi-site synergistic-enhanced capture and recognition" approach to improve the sensitivity of hydrazine vapor detection. Thanks to this strategy, we successfully achieved fluorescence, colorimetric, and electrochemical three-channel sensing of hydrazine vapor.

[0021] In summary, this invention successfully prepared a novel silver-π conductive polymer gel material by coordinating-driven precise self-assembly of A,A'-bispyridinehydrazone-functionalized conjugated columnar aromatic hydrocarbons [5] (PYP5) and silver (I) ions. Based on the "multi-site synergistic-enhanced capture and recognition" strategy, Ag-π-CPG can achieve highly sensitive three-channel detection of hydrazine vapor through electrochemical, colorimetric and fluorescence signal modes. It has high specificity and high sensitivity, and can meet the needs of different scenarios such as rapid on-site detection and low-concentration screening. The novel silver-π conductive polymer gel material provided by this invention has good application prospects in supramolecular assembly, toxic pollutant gas sensing and monitoring and other fields. Attached Figure Description

[0022] Figure 1 This is the phase transition diagram of the silver-π conductive polymer gel sol-gel of the present invention; Figure 2 This is the crystallographic configuration of the smallest structural unit formed by the coordination of PYP5 and Ag(I) ions in this invention; Figure 3The smallest structural unit formed by the coordination of PYP5 and Ag(I) ions in this invention is assembled into a single crystal structure of a one-dimensional chain-like Ag-π supramolecular polymer through Ag···π interaction. Figure 4 This invention relates to the multiple π···π stacking and C–H···π interactions between one-dimensional chain-like Ag-π supramolecular polymers in Ag-π-CPG; Figure 5 This is the crystal packing structure observed along the a-axis in Ag-π-CPG of this invention (hydrogen atoms have been omitted); Figure 6 This is the crystal packing structure observed along the c-axis in Ag-π-CPG of this invention (hydrogen atoms have been omitted); Figure 7 The free volume (FV) and free volume fraction (FVF) of the Ag-π-CPG crystal of this invention are given. Figure 8 The portion of PYP5 in this invention containing Ag⁺ and hydrazine. 1 1H NMR titration chromatograms, where (1): PYP5; (2–5): PYP5 with 0.5, 1.0, 1.5, and 2.0 equivalents of Ag added, respectively. + (6) PYP5+ 2.0 equivalent Ag⁺+ 2.0 equivalent hydrazine.

[0023] Figure 9 The images show the naked-eye colorimetric and fluorescence changes of the silver-π conductive polymer gel Ag-π-CPG of this invention after exposure to different toxic vapors. Figure 10 Photographs of the silver-π conductive polymer gel Ag-π-CPG of the present invention under naked-eye conditions for detecting hydrazine vapor of different concentrations; Figure 11 Photograph of a compact electrode for electrochemical hydrazine vapor sensing using the silver-π conductive polymer gel Ag-π-CPG of the present invention. Figure 12 The present invention provides the electrochemical selectivity of the silver-π conductive polymer gel Ag-π-CPG for different toxic vapors; Figure 13 The conductivity of the silver-π conductive polymer gel Ag-π-CPG of the present invention before and after exposure to different concentrations of hydrazine vapor is shown. Figure 14 The relative conductivity change rate of the silver-π conductive polymer gel Ag-π-CPG of the present invention after exposure to different concentrations of hydrazine vapor; Figure 15 High-resolution mass spectrometry of the silver-π conductive polymer gel Ag-π-CPG of the present invention after its structure was destroyed by exposure to hydrazine vapor and the bispyridine hydrazone functionalized conjugated column[5] aromatic macrocyclic monomer PYP5. Figure 16 High-resolution mass spectrometry of the silver-π conductive polymer gel Ag-π-CPG of the present invention after the structure of the silver-π conductive polymer gel Ag-π-CPG was destroyed by exposure to hydrazine vapor and then the double pyridine hydrazone functionalized conjugated column[5] aromatic macrocyclic PYP5 complexed tetramolecule hydrazine. Figure 17 XPS spectra of the silver-π conductive polymer gel Ag-π-CPG of this invention in the Ag 3d and N 1s regions before and after exposure to hydrazine vapor; Figure 18 The images show scanning electron microscopy (SEM) characterizations of the silver-π conductive polymer gel Ag-π-CPG of this invention before and after exposure to hydrazine vapor. Detailed Implementation

[0024] The following description, in conjunction with the accompanying drawings and examples, further illustrates the specific embodiments of the present invention. The examples are for illustrative purposes only and are not intended to limit the scope of the invention. Unless otherwise specified, all instruments and reagents used are commercially available conventional products.

[0025] Example 1: Preparation of silver-π conductive polymer gel Ag-π-CPG A,A'-bispyridinehydrazone-functionalized conjugated columnar aromatic PYP5 (20 mg, 0.01676 mmol) was added to 160 μL of a DMSO-H2O mixture (water volume fraction) f w =20%), then add 0.03351 mmol of silver trifluoromethanesulfonate (AgCF3SO3), heat to 120℃ to completely dissolve it, let the solution stand, and cool to room temperature to obtain a pale yellow silver-π conductive polymer gel Ag-π-CPG.

[0026] Example 2: Fluorescence sensing of hydrazine vapor by silver-π conductive polymer gel Ag-π-CPG 20 μL of freshly prepared Ag-π-CPG metal gel was coated onto a clean glass slide and exposed to vapors containing 1 ppm hydrazine, ammonia, formaldehyde, acetaldehyde, benzene, pyridine, toluene, diethyl ether, and 1,2-dichloroethane, respectively. The fluorescence changes were then recorded under 365 nm ultraviolet light. If the blue fluorescence of Ag-π-CPG was quenched, it indicated that it was hydrazine vapor; if the blue fluorescence of Ag-π-CPG remained almost unchanged, it indicated that it was another vapor.

[0027] Example 3: Colorimetric Sensing of Hydrazine Vapor by Silver-π Conductive Polymer Gel Ag-π-CPG 20 μL of freshly prepared Ag-π-CPG metal gel was coated onto a clean glass slide and exposed to vapors containing 1 ppm hydrazine, ammonia, formaldehyde, acetaldehyde, benzene, pyridine, toluene, diethyl ether, and 1,2-dichloroethane, respectively. The color changes were then observed with the naked eye under natural light and recorded. If Ag-π-CPG changed from pale yellow to black, it indicated that it was hydrazine vapor; if the color of Ag-π-CPG remained almost unchanged, it indicated that it was another vapor.

[0028] Example 4: Electrochemical sensing of hydrazine vapor by silver-π conductive polymer gel Ag-π-CPG One μL of freshly prepared Ag-π-CPG metal gel was loaded onto a compact electrode fabricated using 3D printing. This electrode was then exposed to vapors containing 10 ppb hydrazine, ammonia, formaldehyde, acetaldehyde, benzene, pyridine, toluene, and 1,2-dichloroethane. The conductivity of the gel before and after exposure to the vapors was measured using a source meter, and the relative conductivity change was calculated. The results showed that only hydrazine vapor caused a significant decrease in conductivity (Δσ / σ0 reached 41.35%), while the conductivity changes caused by the other vapors were negligible.

[0029] The calculation method for relative conductivity change (Δσ / σ0) is as follows: Δσ / σ0 = (σ0 - σ) / σ0 (where: Δσ is the change in conductivity, σ0 is the conductivity before exposure to vapor, and σ is the conductivity after exposure to vapor).

[0030] The above embodiments are merely one of the preferred embodiments of the present invention and should not be used to limit the scope of protection of the present invention. Any modifications or refinements made to the main design concept and spirit of the present invention that are not of substantial significance, but solve the same technical problem as the present invention, should be included within the scope of protection of the present invention.

Claims

1. A silver-π conductive polymer gel material, characterized in that: It is constructed by coordination-driven self-assembly of A,A'-bispyridinehydrazone-functionalized conjugated column[5] aromatics and silver ions; The structural formula of the A,A'-bispyridinehydrazone-functionalized conjugated columnar aromatic hydrocarbon[5] is: 。 2. The silver-π conductive polymer gel material as described in claim 1, characterized in that: Ag + The pyridine nitrogen atom and imine nitrogen atom on the aromatic functional arm of the A,A'-bispyridinehydrazone functionalized conjugated column [5] are coordinated by the Ag–N bond to form a coordination structure unit; the coordination structure unit is further assembled by adjacent Ag···π interactions to form a one-dimensional chain Ag–π supramolecular polymer; the one-dimensional chain Ag–π supramolecular polymers are stacked by multiple C–H···π and / or π···π interactions to form a gel network with an extended conjugated system.

3. The method for preparing the silver-π conductive polymer gel material according to any one of claims 1 or 2, characterized in that, Includes the following steps: The A,A'-bispyridinehydrazone-functionalized conjugated column[5] aromatic host molecule was dissolved in a mixed solvent of DMSO and H2O, and then silver salt was added. The mixture was heated until completely dissolved, and then allowed to stand and cool to obtain silver-π conductive polymer gel material.

4. The method for preparing the silver-π conductive polymer gel material as described in claim 3, characterized in that: The molar ratio of the A,A'-bispyridinehydrazone-functionalized conjugated column[5] aromatic host molecule to silver salt is 1:2-1:

3.

5. The method for preparing the silver-π conductive polymer gel material as described in claim 3, characterized in that: In the mixed solvent of DMSO and H2O, the volume fraction of H2O is 15%~25%.

6. The method for preparing the silver-π conductive polymer gel material as described in claim 3, characterized in that: The silver salt is silver trifluoromethanesulfonate; the heating temperature is 115~125℃.

7. The application of the silver-π conductive polymer gel material as described in claim 1 or 2 in the detection of hydrazine vapor.

8. The application as described in claim 7, characterized in that: The detection is achieved through three signal channels: electrochemical, colorimetric, and fluorescence. The detection limit for electrochemical detection is as low as 5 ppb, and the detection limit for naked-eye colorimetric detection is as low as 0.1 ppm.

9. The application as described in claim 8, characterized in that: The detection method has a specific ability to identify hydrazine vapor, but no obvious signal response to other toxic vapors such as ammonia, formaldehyde, acetaldehyde, benzene, pyridine, toluene, diethyl ether, and 1,2-dichloroethane.

Images