A room temperature self-healing NH3 sensor based on TPA-3DCNPZ and laminated structure and a preparation method thereof

Abstract

The application relates to a room-temperature self-healing NH3 sensor based on a TPA-3DCNPZ and a laminated structure and a preparation method thereof, and belongs to the technical field of gas sensors. From bottom to top, the sensor is composed of a polyurethane (PU) substrate, a silver lower electrode, a TPA-3DCNPZ sensitive material thin film and a gold upper electrode. First, a TPA-3DCNPZ sensitive material spin coating liquid is prepared, then a silver electrode is stably prepared on the PU substrate through a thermal evaporation auxiliary method, and the TPA-3DCNPZ sensitive material thin film and the gold upper electrode are sequentially prepared through a spin coating method and a thermal evaporation method. The application effectively reduces the working temperature of the sensor by using a novel organic sensitive material TPA-3DCNPZ, and the sensor can detect NH3 under room-temperature conditions; the dynamic crosslinking of disulfide bonds of the crosslinked PU substrate after mechanical damage realizes self-healing of the overall device, and the mechanical damage resistance of the device is improved; the sensor has good response recovery characteristics, selectivity and stability.

Description

Technical Field

[0001] This invention belongs to the field of gas sensor technology, specifically relating to a room temperature self-healing ammonia (NH3) sensor based on TPA-3DCNPZ and a stacked structure and its preparation method, which is mainly used for the stable detection of ammonia at room temperature. Background Technology

[0002] In practical applications, NH3 sensors still urgently need to achieve low cost, miniaturization, and portability, especially in respiratory detection applications, where good selectivity and stability are required under complex exhalation environments. Furthermore, the application of flexibility and self-healing properties in device manufacturing has broadened the sensor's applications in areas such as human health. Therefore, developing a real-time, portable, flexible NH3 sensor is of great significance in order to meet the requirements for accurate and stable detection of NH3 in complex application environments.

[0003] Among the many types of NH3 detection devices, resistive chemical sensors are widely used in various complex detection environments due to their portability and high stability. Regarding the selection of sensitive materials for key components of gas sensors, many NH3 sensors based on semiconductor metal oxides and solid electrolytes have been developed; however, their high operating temperature and poor selectivity still limit their application in room temperature detection. Therefore, some novel organic molecular-based NH3 sensors with good room temperature sensing characteristics have been successfully developed. For example, in previously reported work, our research group constructed two room-temperature NH3 sensors based on phenanthrene-pyrazine derivatives (DPA-Ph-DCPzDCN and TPA-DCPP), which exhibited fast response and good stability. The sensing mechanism was attributed to the adsorption of NH3 by pyrazine and cyano groups (J.He, X.Yan, A.Liu, R.You, F.Liu, S.Li, J.Wang, C.Wang, P.Sun, X.Yan, B.Kang, J.He, Y.Wang, G.Lu, A rapid-response room-temperature planar type gas sensor based on DPA-Ph-DBPzDCN for the sensitive detection of NH3, Journal of Materials Chemistry). A, 7(2019)4744-4750; J.He, B.Liang, X.Yan, F.Liu, J.Wang, Z.Yang, R.You, C.Wang, P.Sun, X.Yan, H.Lin, B.Kang, Y.Wang, G.Lu, A TPA-DCPP organic semiconductor film-based room temperature NH3 sensor for insight into the sensing properties, Sensors and Actuators B: Chemical, 327(2021)128940). However, such sensors still suffer from problems such as excessively high baseline resistance, which limits their practical applications. Therefore, it is still necessary to further reduce the baseline resistance of the device and develop more practical and stable NH3 sensors for complex application environments. This invention presents, for the first time, a self-healing NH3 sensor based on the organic material 6,6',6"-(nitrile-4,1-diyl)tris(5-phenylpyrazine-2,3-dicarbonyl) (TPA-3DCNPZ) and its multilayer structure. The TPA-3DCNPZ molecule also possesses abundant pyrazine and cyano groups capable of adsorbing NH3, giving the device excellent response recovery characteristics and selectivity at room temperature. Furthermore, the application of the multilayer structure reduces the device's baseline resistance to 10 Ω.1 With a capacitance in the MΩ range and using self-healing polyurethane (PU) as the device substrate, the overall device can achieve self-healing after mechanical scratches through the cross-linking healing of disulfide bonds. This sensor can detect NH3 quickly and stably at room temperature. Summary of the Invention

[0004] The purpose of this invention is to provide a room-temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure, and its fabrication method. This invention aims to reduce the baseline resistance of the device and improve its stability, thereby promoting the practical application of this sensor in the field of room-temperature NH3 detection. The sensor fabricated by this invention, in addition to having 10... 1 In addition to its resistance in the MΩ range and good selectivity and stability, it also has good response recovery characteristics and self-healing properties.

[0005] The self-healing NH3 sensor described in this invention is a novel room-temperature NH3 sensor constructed using TPA-3DCNPZ organic small molecules with pyrazine and cyano groups as the sensitive material and employing a stacked structure.

[0006] The room-temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure described in this invention, such as... Figure 1 As shown, from bottom to top, the structure consists of a polyurethane (PU) substrate, a lower electrode, a TPA-3DCNPZ sensitive material film, and an upper electrode. The PU substrate possesses self-healing properties (the synthesis process is referenced in Journal of Materials Chemistry A 2022, 10(4), 2012-2020; after mechanical scratching with a scalpel, the PU substrate can achieve self-healing at 80℃ for 5 hours), and the upper and lower electrodes have the same serpentine structure. This invention starts from optimizing the device structure, improving the device's conductivity by shortening the charge transport path in the sensitive material film, thereby reducing the device's resistance. This invention uses gold, which has good conductivity and stability under high humidity and other environments, as the upper electrode, and uses silver, which has good ductility, as the lower electrode to achieve energy level matching and improve the sensitivity characteristics. This invention utilizes a thermal evaporation-assisted method for electrode preparation. During the thermal evaporation process, when silver atoms at temperatures exceeding 80℃ reach the PU substrate surface, the PU surface has a certain fluidity, thus allowing silver to stably adhere to the PU substrate (the thermal resistance theory is used to determine when the silver atom evaporation rate is...). At that time, the temperature at which silver atoms reach the PU surface is 84℃. The thermal resistance theory is referenced in Advanced Materials 2019, 31(35), 1901360, which gives the device good flexibility and self-healing properties.

[0007] The method for fabricating a room-temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure according to the present invention comprises the following steps:

[0008] The chemical structural formula of the TPA-3DCNPZ sensitive material is as follows:

[0009]

[0010] The preparation process of the TPA-3DCNPZ sensitive material is based on ZL CN113816911 B, and the detailed synthesis process is as follows:

[0011] The reagents and chemicals used were: tris(4-bromophenyl)amine, ethylbenzene, cuprous iodide, tetra(triphenylphosphine)palladium, potassium permanganate, diaminopolyacrylonitrile, sodium sulfate, etc., which were purchased from Anaiji Chemical Co., Ltd.; tetrahydrofuran, triethylamine, silica gel, acetone, acetic acid, petroleum ether, ethyl acetate, dichloromethane, and chloroform were all domestically produced analytical grade reagents.

[0012] Synthesis of tris(4-(phenylethyl)phenyl)amine

[0013] Tris(4-bromophenyl)amine (4.8 g, 10.0 mmol) and ethylbenzene (3.6 g, 35.0 mmol) were dissolved in 80 mL of tetrahydrofuran and 80 mL of triethylamine. Then, cuprous iodide (171.9 mg, 0.9 mmol) and Pd(PPh3)Cl2 (631.7 mg, 0.9 mmol) were added under high-flow-rate nitrogen. The reaction mixture was stirred at 70 °C for 24 h. After cooling to room temperature, the mixture was washed with dichloromethane / water. The organic phase was dried over anhydrous sodium sulfate and concentrated. Finally, using petroleum ether / dichloromethane (6:1) as eluent, column chromatography was used to obtain compound 1 (3.4 g, 62.4%) as a milky white powder. 1 H NMR (400MHz, CDCl3) δ7.52(d,J=6.2Hz,1H),7.44(d,J=8.1Hz,1H),7.34(d,J=6.4Hz,1H),7.08(d,J=8.1Hz,1H). 13 CNMR(101MHz, CDCl3)δ146.72(s),132.85(s),131.56(s),128.39(s),128.17(s),124.0 6(s),123.52(d,J=18.7Hz),118.01(s),89.30(d,J=5.1Hz).ESI-MS(M):m / z:545.38[M] + (calcd:545.21).

[0014] Synthesis of 2,2',2"-(nitrotris(phenyl-4,1-diyl))tris(1-phenylethane-1,2-dione)

[0015] Compound 1 (2.0 g, 3.7 mmol) was dissolved in 50 mL of acetone, followed by the addition of potassium permanganate (3.7 g, 23.6 mmol), water (4.6 mL), and glacial acetic acid (1.7 mL). The mixture was refluxed for 8 h. After direct filtration, the mixture was purified by column chromatography using petroleum ether / ethyl acetate (1:1) as the eluent to give compound 2 (1.3 g, 54.8%) as a yellow powder. 1 H NMR (400MHz, CDCl3) δ7.96 (dd, J = 23.6, 8.2Hz, 1H), 7.67 (t, J = 7.3Hz, 1H), 7.53 (t, J = 7.6Hz, 1H), 7.21 (d, J = 8.5Hz, 1H). 13 C NMR(101MHz, CDCl3)δ194.27,192.57,151.18,135.03,132.96,131.90,130.01,129.12(d J=5.6Hz),124.52(s).ESI-MS(M):m / z:641.58[M] + (calcd:641.18).

[0016] Synthesis of 6,6',6"-(nitrile-4,1-diyl)tris(5-phenylpyrazine-2,3-dicarbonyl) (TPA-3DCNPZ)

[0017] Compound 2 (1.3 g, 2.0 mmol) and diaminopolyacrylonitrile (0.9 g, 8.3 mmol) were dissolved in 50 mL of glacial acetic acid and refluxed for 18 h. The reaction mixture was poured into water, cooled to room temperature, and filtered. The mixture was purified by column chromatography using petroleum ether / dichloromethane (1:2) as eluent to give an orange-red solid (1.4 g, 81.7%). 1 H NMR (400MHz, CD2Cl2) δ7.60(d,J=7.3Hz,1H),7.50(d,J=8.7Hz,2H),7.42(t,J=7.5Hz,1H),7.06(d,J=8.7Hz,1H). 13C NMR (101MHz, CDCl3) δ155.09(s), 154.09(s), 148.54(s), 135.49(s), 131.47(d, J=22.6Hz), 131.33-131.09(m ),130.56(s),129.73(d,J=14.4Hz),129.25(s),129.04(s),24.27(s),113.25(s).ESI-MS(M):m / z:858.26[M] + (calcd:858.25).Anal.Calcd for C 54 H 27 N 13 :C,75.60;H,3.17;N,21.23.Found:C,75.66;H,3.10;N,21.11.

[0018] Sensor fabrication:

[0019] (1) Cut a PU film with self-healing properties into a planar substrate with dimensions of (0.8~1.2)cm×(1.5~2)cm and a thickness of 450~500μm to obtain a PU substrate;

[0020] (2) Place the mask with the serpentine lower electrode structure on the PU substrate obtained in step (1), and first use... Vacuum thermal evaporation of Ag films with a thickness of 600–800 nm was performed at a high evaporation rate, followed by… An 80–120 nm thick Ag film was vacuum thermally deposited at a high evaporation rate to improve the flatness of the Ag film, thereby obtaining a serpentine silver lower electrode with a total thickness of 680–920 nm, at a vacuum degree of 1 × 10⁻⁶. 6 Torr;

[0021] (3) Preparation of sensitive material spin coating solution: Mix 0.5-1.5 mL of CHCl3 with 18-22 mg of TPA-3DCNPZ sensitive material powder and stir evenly to obtain sensitive material spin coating solution;

[0022] (4) Spin coat the sensitive material spin coating liquid obtained in step (3) onto the PU substrate with the serpentine structure silver lower electrode obtained in step (2), with a spin coating rate of 800-1200 rad / s, a spin coating time of 50-80s, and spin coating 1-3 layers. Then dry the organic solvent at 60-80℃. The thickness of the obtained TPA-3DCNPZ sensitive material film is 400-600 nm.

[0023] (5) Place the device obtained in step (4) on a mask with a serpentine upper electrode structure, so as to A 100–200 nm thick Au film was vacuum thermally deposited as the upper electrode at a vacuum level of 1 × 10⁻⁶. 6 Torr, thereby preparing the room temperature self-healing NH3 sensor based on TPA-3DCNPZ and stacked structure as described in this invention.

[0024] Advantages of this invention:

[0025] (1) By using the novel organic material TPA-3DCNPZ as the sensing material, the operating temperature of the sensor is effectively reduced, and NH3 can be detected at room temperature.

[0026] (2) The sensor is fabricated using a stacked structure of substrate / lower electrode / sensitive material thin film / upper electrode. By shortening the charge transport path, the baseline resistance of the sensor is effectively reduced. By optimizing the selection of the lower electrode material, better energy level matching is achieved, thereby improving the sensitivity of the sensor.

[0027] (3) Using a PU film with self-healing properties as a substrate, the lower electrode is stably attached to the substrate by vacuum thermal evaporation, thereby enabling the sensor to have self-healing flexibility and enhancing the mechanical stability and resistance to mechanical damage of the device in complex application environments. Attached Figure Description

[0028] Figure 1 : A schematic diagram of the room temperature self-healing NH3 sensor structure based on TPA-3DCNPZ and stacked structure described in this invention.

[0029] The names of each part are: PU substrate 1, serpentine structure silver lower electrode 2, TPA-3DCNPZ sensitive material film 3, serpentine structure gold upper electrode 4.

[0030] Figure 2 The graphs (a) and (b) show the baseline resistance and response to 100 ppm NH3 of TPA-3DCNPZ sensors (denoted as PU / Au / TPA-3DCNPZ / Au and PU / Ag / TPA-3DCNPZ / Au, respectively) fabricated using gold (Au) and silver (Ag) as bottom electrodes, respectively, at room temperature and 15% RH and 98% RH. (The response value of the device is represented by S = ΔR / R.) 空气 This means that ΔR = R 空气 -R 氨气 R is the resistance value of the thin film between the upper and lower electrodes of the sensor under different atmospheres or gas concentrations.

[0031] like Figure 2As shown in (a), the baseline resistance values ​​of the PU / Au / TPA-3DCNPZ / Au device are 5.5 MΩ and 4.7 MΩ at room temperature and at 15% RH and 98% RH, respectively, while the baseline resistance values ​​of the PU / Ag / TPA-3DCNPZ / Au device are 3.48 MΩ and 3.5 MΩ, respectively. The resistance values ​​of all devices are within 10... 1 The MΩ level indicates that the application of the layered structure can effectively reduce the device resistance and improve the conductivity of the gas sensor based on TPA-3DCNPZ organic small molecules. For example... Figure 2 As shown in (b), at room temperature and relative humidity of 15% RH and 98% RH, the response values ​​of the PU / Au / TPA-3DCNPZ / Au device to 100 ppm NH3 are 4% and 13.6%, respectively, while the response values ​​of the PU / Ag / TPA-3DCNPZ / Au device to 100 ppm NH3 are 23.2% and 11.4%, respectively. This indicates that the PU / Ag / TPA-3DCNPZ / Au device has a high response value, and exhibits the highest response value to NH3 at 98% RH. According to the energy level matching theory, when Ag is used as the lower electrode, the charge extraction capability of the electrode is enhanced, and the device exhibits better gas-sensing characteristics.

[0032] Figure 3 The response recovery curve of the sensor using TPA-3DCNPZ at 98% RH as the sensing material and Ag as the lower electrode in 20ppm NH3 (where the horizontal axis is time and the vertical axis is the response value).

[0033] like Figure 3 As shown, the device has a response value of 15.8% to 20ppm NH3, a response time of 49s, and a recovery time of 25s, exhibiting a fast response and recovery speed. Furthermore, the device recovers well to the baseline resistance, demonstrating good response and recovery characteristics.

[0034] Figure 4 Selectivity histograms of different gases for an NH3 sensor using TPA-3DCNPZ as the sensing material and Ag as the lower electrode (where the horizontal axis is the response value and the vertical axis is the test gas: from top to bottom, they are NH3, ethanol, nitrogen dioxide, carbon monoxide, acetone and benzene).

[0035] like Figure 4 As shown, the device exhibits the greatest sensitivity to NH3, while the response to other interfering gases is relatively low, thus demonstrating that the device has excellent selectivity.

[0036] Figure 5 Stability curves of an NH3 sensor using TPA-3DCNPZ as the sensing material and Ag as the lower electrode (where the horizontal axis represents time and the vertical axis represents the response value).

[0037] like Figure 5 As shown in the figure, the device's response value fluctuates very little over 15 days, indicating that the device has good stability.

[0038] Figure 6 SEM images of an NH3 sensor using TPA-3DCNPZ as the sensing material and Ag as the lower electrode after mechanical scratching with a scalpel (a, the longitudinal range of the scratch extends from the gold upper electrode to the PU film); SEM image of the scratched device after self-healing at 80℃ for 5 hours (b); and baseline resistance and response to 20ppm NH3 of the device before and after self-healing at 98%RH (c) (where the left ordinate is the baseline resistance of the device and the right ordinate is the response).

[0039] like Figure 6 As shown in (a, b), the entire device achieves healing through dynamic cross-linking of disulfide bonds in the PU substrate. However, the rigidity of the metal electrodes results in a blocky electrode distribution after healing, as... Figure 6 As shown in (c), the device resistance increases to 5.4 MΩ, and the response value to 20 ppm NH3 decreases to 14.3%, indicating that the device still maintains good gas-sensing characteristics after self-healing. Detailed Implementation

[0040] Comparative Example 1:

[0041] An Au lower electrode and TPA-3DCNPZ organic material were fabricated on a PU substrate using thermal evaporation and spin coating methods, respectively. An Au upper electrode was then fabricated using thermal evaporation to prepare an NH3 sensor. The gas-sensing performance of the sensor was then tested. The specific process is as follows:

[0042] 1. Preparation of PU substrate: The PU film with self-healing properties is cut into a planar substrate with a size of 1 cm × 1.8 cm and a thickness of 460 μm to obtain the PU substrate;

[0043] 2. Fabrication of the Au lower electrode: A mask with a serpentine lower electrode structure is placed on the PU substrate obtained in step 1, and vacuum thermal evaporation is used to deposit the Au electrode. A 300 nm thick Au film was vacuum thermally deposited as the lower electrode at a deposition rate of 1 × 10⁻⁶. 6 Torr;

[0044] 3. Preparation of TPA-3DCNPZ sensitive film: Measure 1 mL of chloroform (CHCl3), weigh 20 mg of TPA-3DCNPZ sensitive material powder, mix CHCl3 and TPA-3DCNPZ powder and stir evenly to prepare a spin-coating solution of 20 mg / mL;

[0045] 4. Spin-coating solution was spin-coated onto a PU substrate with an Au lower electrode at a spin-coating rate of 1000 rad / s and a spin-coating time of 60 s, resulting in one layer; then the solvent was dried at 70 °C, and the thickness of the obtained TPA-3DCNPZ sensitive film was 500 nm.

[0046] 5. Fabrication of the Au top electrode: A mask with a serpentine top electrode structure is placed on the device obtained in step 4, and vacuum thermal evaporation is used to deposit the Au top electrode. A 150 nm thick Au film was deposited as the top electrode at a evaporation rate of 1 × 10⁻⁶. 6 Torr was used to fabricate the PU / Au / TPA-3DCNPZ / Au sensor.

[0047] Example 1:

[0048] An Ag lower electrode was prepared by thermal evaporation to fabricate an NH3 sensor. The specific process is as follows:

[0049] The PU substrate obtained in step 1 of Comparative Example 1 was placed on a mask with a serpentine lower electrode structure, and vacuum thermal evaporation was used to first... A 700 nm thick Ag film was vacuum thermally deposited at a deposition rate of [percentage missing], and then [deposited using] [method missing]. A 100 nm thick Ag film was vacuum thermally deposited at a high evaporation rate to improve the flatness of the Ag film, thereby obtaining a serpentine silver lower electrode with a total thickness of 800 nm and a vacuum degree of 1 × 10⁻⁶. 6 Torr. The fabrication process for the remaining components is the same as in Comparative Example 1.

[0050] Bombarding PU films with high-temperature metal atoms for too long will reduce the mechanical properties of the PU film. Au If the evaporation rate is too high and the evaporation time is too long (800 nm), the PU film will lose some mechanical properties, and the bond between the upper metal layer and the PU film will not be strong enough, thus reducing electrode stability. Electrode thickness is a factor affecting device performance. According to the reference proposing the thermal evaporation-assisted method (Advanced Materials 2019, 31(35), 1901360), the mechanical properties of the device are optimal when the Au electrode thickness is 300 nm. The silver electrode thickness of 800 nm combines the advantages of evaporation time and device mechanical stability.

[0051] The sensors obtained in Comparative Example 1 and Example 1 were connected to a Fluke 8846a resistance tester and subjected to resistance signal tests in air at 15%RH, 98%RH, 20ppmNH3, and 100ppmNH3 atmospheres, respectively.

[0052] Table 1: Baseline resistance and response to 100ppmNH3 of the TPA-3DCNPZ sensor with Au and Ag as lower electrodes at 15%RH and 98%RH.

[0053]

[0054] Table 2: Baseline resistance and response to 20 ppm NH3 of the NH3 sensor with Ag as the lower electrode and TPA-3DCNPZ as the sensing material before and after self-healing at 98% RH.

[0055] Device status No mechanical damage After self-healing Device baseline resistance (MΩ) 3.5 5.4 <![CDATA[20 ppm NH3 response value]]> 15.8％ 14.3％

[0056] Table 1 lists the baseline resistance values ​​and response values ​​to 100 ppm NH3 of NH3 sensors using Au and Ag as the lower electrode and TPA-3DCNPZ as the sensing material at 15% RH and 98% RH, respectively. As can be seen from the table, both devices exhibit a resistance of 10... 1 The resistance value in the MΩ range indicates that the application of the stacked structure effectively improves the conductivity of the organic small molecule-based gas sensor. Among them, the device with Ag as the lower electrode exhibits the highest response value of 23.2% at 98% RH. This shows that for the stacked structure, by rationally selecting the upper and lower electrodes to achieve energy level matching, the charge extraction capability of the electrodes is enhanced, thereby improving the sensitivity of the sensor.

[0057] Table 2 lists the self-healing performance of the NH3 sensor with Ag as the lower electrode and TPA-3DCNPZ as the sensing material at 98% RH. After being scratched by a scalpel, the device achieved self-healing after being placed at 80°C for 5 hours. The baseline resistance and response to 20 ppm NH3 values ​​before and after self-healing are recorded. The device resistance increased by 1.9 MΩ, and the response to 20 ppm NH3 decreased by 1.5%, but the device still exhibited good NH3 sensing ability. This demonstrates that the currently constructed room temperature NH3 sensor based on TPA-3DCNPZ and a stacked structure possesses excellent gas-sensing and self-healing properties, showing great potential for applications in room temperature NH3 detection.

Claims

1. A method for fabricating a room-temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure, comprising the following steps: (1) Cut a polyurethane film with self-healing properties into a planar substrate with a thickness of 450-500 μm to obtain a polyurethane substrate; (2) Place the mask with the lower electrode structure on the polyurethane substrate obtained in step (1), and first use... Vacuum thermal evaporation of Ag films with a thickness of 600–800 nm was performed at a high evaporation rate, followed by… Vacuum thermal evaporation of an 80–120 nm thick Ag film was achieved at a high evaporation rate, resulting in a serpentine silver lower electrode with a total thickness of 680–920 nm. (3) Preparation of the spin-coating solution for the sensitive material: Mix 0.5-1.5 mL of CHCl3 with 18-22 mg of TPA-3DCNPZ sensitive material powder and stir evenly to obtain the spin-coating solution for the sensitive material; the chemical structural formula of TPA-3DCNPZ sensitive material is as follows, (4) Spin coat the sensitive material spin coating liquid obtained in step (3) onto the polyurethane substrate with silver lower electrode obtained in step (2), with a spin coating rate of 800-1200 rad / s, a spin coating time of 50-80s, spin coating 1-3 layers, and then dry the organic solvent. The thickness of the obtained TPA-3DCNPZ sensitive material film is 400-600 nm. (5) Place the mask with the upper electrode structure onto the device obtained in step (4) to... A 100-200 nm thick Au film was vacuum thermally deposited at a high evaporation rate to serve as the upper electrode, thereby preparing the room temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure.

2. The method for fabricating a room-temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure as described in claim 1, characterized in that: The upper and lower electrodes have the same serpentine structure.

3. The method for fabricating a room-temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure as described in claim 1, characterized in that: The silver electrode deposition rate is Vacuum degree is 1×10 6 Torr; The temperature for drying organic solutions is 60–80°C.

4. A room-temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure, characterized in that: It is prepared by the method described in any one of claims 1 to 3.

5. The room temperature self-healing NH3 sensor based on TPA-3DCNPZ and a stacked structure as described in claim 4 is used for the stable detection of ammonia at room temperature.

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