Metal nickel phthalocyanine polymer as well as preparation method and application thereof

Abstract

The invention provides a metallic nickel phthalocyanine polymer as well as a preparation method and application thereof, and relates to the technical field of sulfur dioxide room temperature detection. The polymer is obtained by tetramerization reaction of a sulfur-containing o-dicyano precursor and nickel acetate tetrahydrate, and the structural formula of the polymer is as shown in formula 1. The metal nickel phthalocyanine polymer is used for sulfur dioxide sensing detection and used as a gas sensitive material of sulfur dioxide, in the preparation process, the metal nickel phthalocyanine polymer is dropwise added to a glass substrate with an ITO interdigital electrode to serve as a semiconductor active layer, sensitive and rapid detection of sulfur dioxide with the concentration of 5-30 ppm under the room temperature condition is achieved, and the sensitivity is 0.194%. Ppm <-1 >.

Description

Technical Field

[0001] The invention relates to the technical field of room temperature detection of sulfur dioxide, and in particular to a metal nickel phthalocyanine polymer and a preparation method and application thereof. Background Art

[0002] Fossil fuels such as coal and oil are the main components of energy supply and are widely used in power plants, vehicles and heavy equipment, chemical industry and many other fields. Their use will inevitably produce SO2 gas emissions. SO2 gas is particularly corrosive to the eyes. Long-term exposure to low concentrations of SO2 can cause symptoms such as bronchitis, pharyngitis, rhinitis, headache, fatigue, and impaired taste and smell. Therefore, its detection and monitoring are of great significance in the fields of environmental protection and industrial safety.

[0003] Gas-sensitive materials are the core part of gas sensors, and their performance directly determines the sensitivity, selectivity and stability of the sensor. At present, common gas-sensitive materials include: Semiconductor oxides (such as SnO2, ZnO): have high sensitivity, but perform poorly under low temperature conditions. Metal organic frameworks (MOFs): have excellent selectivity for certain gases, but poor stability. Polymer materials: Selectivity can be improved through functionalization, but the conductivity is low. Metal phthalocyanine materials: Phthalocyanine compounds have a strong interaction with gas molecules due to their planar molecular structure and π-π stacking characteristics, and exhibit excellent gas-sensitive properties, especially in the field of electrochemical sensing.

[0004] Metal phthalocyanine is a polycyclic aromatic compound with a stable π-conjugated structure. The combination of metal phthalocyanine and polymer has brought new possibilities for the development of gas-sensitive materials: High stability: Phthalocyanine molecules have good chemical stability and heat resistance. High selectivity: The metal center in its molecular structure can interact specifically with gas molecules, thereby improving selectivity. Strong adjustability: The performance of gas-sensitive materials can be adjusted by changing the central metal or peripheral groups. Excellent electrical properties: Metal phthalocyanine polymers have good electrical conductivity, which is conducive to gas molecule adsorption and electrical signal conversion.

[0005] At present, there has been some progress in the research of metal phthalocyanine as gas sensor. Many studies focus on its application in gas sensing of nitrogen dioxide and ammonia, but it is rarely used for sulfur dioxide. Summary of the invention

[0006] The purpose of the present invention is to provide a metal nickel phthalocyanine polymer and a preparation method and application thereof. In the present invention, a sulfur-containing o-dicyano precursor and nickel acetate tetrahydrate are reacted through tetramerization to obtain a metal nickel phthalocyanine conjugated polymer, which is used as an active material for the detection of sulfur dioxide. The material can realize sensitive detection of sulfur dioxide at room temperature.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] The present invention first provides a metal nickel phthalocyanine polymer, the structural formula of which is shown in Formula 1:

[0009]

[0010] The present invention also provides a method for preparing a metal nickel phthalocyanine polymer, comprising:

[0011] Step 1: under nitrogen protection, add the precursor of the metal nickel phthalocyanine polymer shown in formula 2, nickel acetate tetrahydrate and n-pentanol into a reaction container, heat to 90° C., add 1,8-diazabicycloundec-7-ene, continue heating reaction, and obtain a reaction product;

[0012]

[0013] Step 2: After the reaction container is cooled to room temperature, methanol is added and allowed to stand, and the metal nickel phthalocyanine polymer is obtained after filtration and drying.

[0014] Preferably, the molar ratio of the metal nickel phthalocyanine polymer precursor to nickel acetate tetrahydrate is 4:10.

[0015] Preferably, the mass mg of the metal nickel phthalocyanine polymer precursor: the volume mL of 1,8-diazabicycloundec-7-ene is 100:0.3.

[0016] Preferably, the reaction temperature of step 1 is 140° C. and the reaction time is 8-10 h.

[0017] Preferably, the method for preparing the precursor of the metal nickel phthalocyanine polymer comprises:

[0018] Step 1: 4-nitrophthalonitrile and 1,3-propanedithiol are added to DMF to dissolve, and then anhydrous potassium carbonate is added and stirred to obtain a reaction product;

[0019] Step 2: adding deionized water to the product obtained in step 1 and stirring, then filtering, washing and drying, and adding methanol to the dried product for reflux reaction to obtain a precursor of the metal nickel phthalocyanine polymer shown in formula 2;

[0020]

[0021] Preferably, in step 1, the mass ratio of 4-nitrophthalonitrile to 1,3-propanedithiol is 2:0.5.

[0022] Preferably, in step 2, the reaction temperature is 65° C. and the reaction time is 1-5 h.

[0023] The present invention also provides application of the metal nickel phthalocyanine polymer as a sulfur dioxide gas-sensitive material.

[0024] The present invention also provides a method for preparing the above sulfur dioxide gas-sensitive material, comprising:

[0025] Step 1: Wash the etched ITO electrode, then ultrasonically treat it with distilled water, anhydrous ethanol, and dichloromethane for 5 to 10 minutes each, and blow dry it with nitrogen;

[0026] Step 2: dispersing the metal nickel phthalocyanine polymer in isopropanol and ultrasonicating for 2 to 3 hours to obtain a dispersion;

[0027] Step 3: Add the prepared dispersion dropwise onto the water layer of the watch glass and let it stand for 5 to 10 minutes;

[0028] Step 4: Use the vertical pulling method to dip the nickel phthalocyanine polymer on the water layer of the surface dish with the etched ITO electrode to obtain the sulfur dioxide gas-sensitive material.

[0029] Beneficial Effects of the Invention

[0030] The present invention provides a metal nickel phthalocyanine polymer and a preparation method and application thereof. The polymer is obtained by tetramerization of a sulfur-containing o-dicyano precursor and nickel acetate tetrahydrate, and the structural formula is shown in Formula 1. The present invention uses the metal nickel phthalocyanine polymer for sulfur dioxide sensing detection and is used as a sulfur dioxide gas-sensitive material. In the preparation process, the metal nickel phthalocyanine polymer is dripped onto a glass substrate with an ITO interdigital electrode as a semiconductor active layer, and a sensitive and rapid detection of sulfur dioxide with a concentration of 5-30 ppm is achieved under room temperature conditions, with a sensitivity of 0.194%·ppm. -1 .

[0031] The gas-sensitive material preparation process and equipment of the present invention are simple and easy to realize industrial production. The preparation of metal nickel phthalocyanine polymer can effectively increase the conjugation degree of phthalocyanine and further improve the electron migration ability. At the same time, the application of phthalocyanine compounds in the field of sensing is expanded. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a gas-sensitivity test diagram of the metal nickel phthalocyanine conjugated polymer to sulfur dioxide in Example 2 of the present invention;

[0033] Figure 2 This is the IV curve of the metal nickel phthalocyanine conjugated polymer of Example 1 of the present invention;

[0034] Figure 3 The ultraviolet diffuse reflection of the metal nickel phthalocyanine conjugated polymer of Example 1 of the present invention;

[0035] Figure 4 This is a SEM image of the metal nickel phthalocyanine conjugated polymer of Example 1 of the present invention;

[0036] Figure 5 This is the infrared spectrum of the metal nickel phthalocyanine conjugated polymer of Example 1 of the present invention;

[0037] Figure 6 This is the NMR spectrum of the metal nickel phthalocyanine conjugated polymer of Example 1 of the present invention. DETAILED DESCRIPTION

[0038] The present invention first provides a metal nickel phthalocyanine polymer, the structural formula of which is shown in Formula 1:

[0039]

[0040] The present invention also provides a method for preparing a metal nickel phthalocyanine polymer, comprising:

[0041] Step 1: Under nitrogen protection, add the precursor of the metal nickel phthalocyanine polymer shown in Formula 2, nickel acetate tetrahydrate and n-pentanol into the reaction container, heat to 90°C, add 1,8-diazabicycloundec-7-ene, and continue heating reaction. The reaction temperature is preferably 140°C, and the reaction time is preferably 8-10h. The reaction product is obtained; the molar ratio of the metal nickel phthalocyanine polymer precursor to nickel acetate tetrahydrate is 4:10; the mass mg of the metal nickel phthalocyanine polymer precursor: the volume mL of 1,8-diazabicycloundec-7-ene is 100:0.3;

[0042]

[0043] Step 2: After the reaction container is cooled to room temperature, methanol is added and allowed to stand, the standing time is preferably 6-8 hours, filtered and dried, the drying temperature is preferably 50-60°C, and the drying time is preferably 12-24 hours. The obtained solid is centrifuged with deionized water for multiple times until the aqueous phase is colorless to remove the metal salt in the product, and finally the centrifuged product is dried, the drying temperature is preferably 50-60°C, and the drying time is preferably 24-48 hours to obtain a metal nickel phthalocyanine polymer.

[0044] According to the present invention, the method for preparing the precursor of the metal nickel phthalocyanine polymer comprises:

[0045] Step 1: adding 4-nitrophthalonitrile and 1,3-propanedithiol to DMF to dissolve, then adding anhydrous potassium carbonate and stirring, the stirring temperature is preferably room temperature, and the stirring time is preferably 24-48 hours to obtain a reaction product; the mass ratio of the 4-nitrophthalonitrile, 1,3-propanedithiol and anhydrous potassium carbonate is 2:0.5:3.19;

[0046] Step 2: Add deionized water to the product obtained in step 1 and stir. The stirring temperature is preferably room temperature and the stirring time is preferably 1-5 hours. Then, the product is filtered with a Buchner funnel and washed with deionized water and methanol for multiple times. Then, it is dried. The drying temperature is preferably 50-60°C and the drying time is preferably 24-48 hours. The dried product is added with methanol for reflux reaction. The reaction temperature is preferably 65°C and the reaction time is preferably 1-5 hours. After the reaction is completed, the reactor is taken out and cooled to room temperature, and filtered with a Buchner funnel. The filtered solid is preferably placed in a vacuum drying oven at 50-60°C and dried for 12-24 hours to obtain a precursor of the metal nickel phthalocyanine polymer shown in Formula 2.

[0047]

[0048] The present invention also provides application of the metal nickel phthalocyanine polymer as a sulfur dioxide gas-sensitive material.

[0049] The present invention also provides a method for preparing the above sulfur dioxide gas-sensitive material, comprising:

[0050] Step 1: Wash the etched ITO electrode, then ultrasonically treat it with distilled water, anhydrous ethanol, and dichloromethane for 5 to 10 minutes each, and blow dry it with nitrogen;

[0051] Step 2: Disperse the metal nickel phthalocyanine polymer in isopropanol and ultrasonicate for 2-3 hours to obtain a dispersion; the mass mg of the metal nickel phthalocyanine polymer: the volume mL of isopropanol is (5-10): (2-4);

[0052] Step 3: drop the prepared dispersion onto the water layer of the watch glass and let it stand for 5 to 10 minutes; the amount of dispersion added is 10 μL;

[0053] Step 4: Use the vertical pulling method to dip the nickel phthalocyanine polymer on the water layer of the surface dish with the etched ITO electrode to obtain the sulfur dioxide gas-sensitive material.

[0054] According to the present invention, the etched ITO electrode with the metal nickel phthalocyanine polymer is subjected to a gas-sensing test on a Keysight B2912A instrument, and finally the detection condition of the metal nickel phthalocyanine conjugated polymer for sulfur dioxide gas at room temperature is obtained.

[0055] The present invention is further described in detail below with reference to specific examples, and the raw materials involved in the examples are all commercially available.

[0056] Example 1 Preparation of Metal Nickel Phthalocyanine Polymer Precursor

[0057] Take 2g 4-nitrophthalonitrile and 0.5g 1,3-propanedithiol and add them to 10mL DMF; after complete dissolution, add 3.19g anhydrous potassium carbonate and stir at room temperature for 24h; add deionized water to the above product and continue stirring for 1h; after stirring, filter the product with a Buchner funnel, and wash it with deionized water and methanol for multiple times; place the obtained product in a 60℃ vacuum drying oven and dry it for 24h; pour the dried product into a single-mouth bottle, add methanol, and reflux it at 65℃ with a stirring reflux device for 1h; after the reaction is completed, take out the reactor and cool it to room temperature, filter it with a Buchner funnel, and place the filtered solid in a 60℃ vacuum drying oven and dry it for 12h to obtain a precursor of a metal nickel phthalocyanine polymer.

[0058] Example 2 Preparation of Metal Nickel Phthalocyanine Polymer

[0059] 100 mg of metal nickel phthalocyanine polymer precursor and 172.590 mg of nickel acetate tetrahydrate were added into a 50 mL microreactor (the molar ratio of precursor to metal salt was 4:10); a double-row tube was connected to the microreactor with a rubber tube and a glass stopper was plugged in. First, evacuate for 10 minutes, then pass nitrogen for 10 minutes, and repeat this process 3 times; keep passing nitrogen, use a syringe to draw 2mL of n-pentanol (distilled and dehydrated) and add it to the reactor; set the oil bath to 90°C, add 0.3mL of 1,8-diazabicycloundec-7-ene (DBU); set the oil bath temperature to 140°C, and react for 10 hours; after the reaction, lift the reaction device, cool to room temperature, add methanol, and let it stand for 8 hours; filter, and put the filtered solid into a 60°C vacuum drying oven and dry it for 24 hours; the solid should be centrifuged with deionized water several times until the water phase is colorless to remove the metal salt in the product; finally, the centrifuged product is placed in a 60°C vacuum drying oven and dried for 48 hours to obtain a metal nickel phthalocyanine polymer.

[0060] Figure 2 This is the IV curve of the metal nickel phthalocyanine conjugated polymer of Example 2 of the present invention; Figure 2 It can be seen that the polymer has a good electrical conductivity of 3.3×10 -3 S cm -1 .

[0061] Figure 3 The ultraviolet diffuse reflection of the metal nickel phthalocyanine conjugated polymer of Example 2 of the present invention; Figure 3 This shows that the ultraviolet diffuse reflectance spectrum of phthalocyanine mainly shows two strong absorption peaks, which are also the two characteristic absorption bands of phthalocyanine: the peak at 600-800nm ​​is the Q band, and the peak at 300-400nm is called the Soret band.

[0062] Figure 4This is a SEM image of the metal nickel phthalocyanine conjugated polymer of Example 2 of the present invention; Figure 4 This indicates that the prepared polymer has a lamellar structure.

[0063] Figure 5 This is the infrared spectrum of the metal nickel phthalocyanine conjugated polymer of Example 2 of the present invention; C≡N 2230cm -1 C-S741cm -1 , C=N~1724cm -1 , C=C~1604cm -1 , CC~1144cm -1 , CH~1084cm -1 , CN~1253cm -1 , Ni-N 558cm -1 , C≡N 2230cm -1 The presence or absence of is a clear difference between the precursor and the metal nickel phthalocyanine polymer.

[0064] Figure 6 This is the NMR spectrum of the metal nickel phthalocyanine conjugated polymer of Example 2 of the present invention, which shows that the polymer is successfully prepared in the present invention.

[0065] Example 3

[0066] The etched ITO electrode was cleaned, and then ultrasonically treated with distilled water, anhydrous ethanol, and dichloromethane for 10 minutes each, and dried with nitrogen; the metal nickel phthalocyanine polymer was dispersed in isopropanol and ultrasonicated for 2.5 hours to obtain a dispersion; the mass mg of the metal nickel phthalocyanine polymer: the volume mL of isopropanol was 5:2; the prepared dispersion was dripped onto the water layer of the watch dish and allowed to stand for 10 minutes; the amount of the dispersion added was 10 μL; the metal nickel phthalocyanine polymer on the water layer of the watch dish was dipped into the etched ITO electrode by a vertical pulling method, and the etched ITO electrode with the metal nickel phthalocyanine polymer was subjected to a gas-sensitive test on a Keysight B2912A instrument, and finally the detection of sulfur dioxide gas by the metal nickel phthalocyanine conjugated polymer at room temperature was obtained.

[0067] Figure 1 This is a gas-sensitive test diagram of the metal nickel phthalocyanine conjugated polymer to sulfur dioxide in Example 3 of the present invention; Figure 1 A is the gas sensitivity test diagram of metal nickel phthalocyanine conjugated polymer to sulfur dioxide. Figure 1 B is the linear relationship between sulfur dioxide concentration and current change. It can be seen from the figure that the metal nickel phthalocyanine conjugated polymer has good sensitivity to sulfur dioxide, with a detection range of 5-30ppm and a sensitivity of 0.194%·ppm -1 .

[0068] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any ordinary technician familiar with the profession can smoothly implement the present invention according to the drawings and the above description. However, any technician familiar with the profession can make some changes, modifications and equivalent changes made by using the technical content disclosed above without departing from the scope of the technical solution of the present invention, which are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the implementation technology of the present invention are within the protection scope of the technical solution of the present invention.

Claims

1. A metal nickel phthalocyanine polymer, characterized in that: The structural formula is shown in Formula 1:

2. The method for preparing a metal nickel phthalocyanine polymer according to claim 1, characterized in that: include: Step 1: under nitrogen protection, add the precursor of the metal nickel phthalocyanine polymer shown in formula 2, nickel acetate tetrahydrate and n-pentanol into a reaction container, heat to 90° C., add 1,8-diazabicycloundec-7-ene, continue heating reaction, and obtain a reaction product; Step 2: After the reaction container is cooled to room temperature, methanol is added and allowed to stand, and the metal nickel phthalocyanine polymer is obtained after filtration and drying.

3. The method for preparing a metal nickel phthalocyanine polymer according to claim 2, characterized in that: The molar ratio of the metal nickel phthalocyanine polymer precursor to nickel acetate tetrahydrate is 4:

10.

4. The method for preparing a metal nickel phthalocyanine polymer according to claim 2, characterized in that: The mass mg of the metal nickel phthalocyanine polymer precursor: the volume mL of 1,8-diazabicycloundec-7-ene is 100:0.

3.

5. The method for preparing a metal nickel phthalocyanine polymer according to claim 2, characterized in that: The reaction temperature of step 1 is 140° C. and the reaction time is 8-10 h.

6. The method for preparing a metal nickel phthalocyanine polymer according to claim 2, characterized in that: The method for preparing the precursor of the metal nickel phthalocyanine polymer comprises: Step 1: 4-nitrophthalonitrile and 1,3-propanedithiol are added to DMF to dissolve, and then anhydrous potassium carbonate is added and stirred to obtain a reaction product; Step 2: adding deionized water to the product obtained in step 1 and stirring, then filtering, washing and drying, and adding methanol to the dried product for reflux reaction to obtain a precursor of the metal nickel phthalocyanine polymer shown in formula 2; 7. The method for preparing a metal nickel phthalocyanine polymer according to claim 6, characterized in that: In step 1, the mass ratio of 4-nitrophthalonitrile to 1,3-propanedithiol is 2:0.

5.

8. The method for preparing a metal nickel phthalocyanine polymer according to claim 6, characterized in that: In step 2, the reaction temperature is 65° C. and the reaction time is 1-5 h.

9. Use of the metal nickel phthalocyanine polymer according to claim 1 as a sulfur dioxide gas-sensitive material.

10. The method for preparing a sulfur dioxide gas-sensitive material according to claim 9, characterized in that: include: Step 1: Wash the etched ITO electrode, then ultrasonically treat it with distilled water, anhydrous ethanol, and dichloromethane for 5 to 10 minutes each, and blow dry it with nitrogen; Step 2: dispersing the metal nickel phthalocyanine polymer in isopropanol and ultrasonicating for 2 to 3 hours to obtain a dispersion; Step 3: Add the prepared dispersion dropwise onto the water layer of the watch glass and let it stand for 5 to 10 minutes; Step 4: Use the vertical pulling method to dip the nickel phthalocyanine polymer on the water layer of the surface dish with the etched ITO electrode to obtain the sulfur dioxide gas-sensitive material.

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