Phthalocyanine cobalt / pyridine nitrogen skeleton substituted phthalocyanine copper / asphalt coke activated carbon composite catalytic material, preparation method and application thereof

Abstract

The application discloses a phthalocyanine cobalt / pyridine nitrogen skeleton substituted phthalocyanine copper / asphalt coke active carbon composite catalytic material and a preparation method and application thereof, and the method comprises the following steps: 1, pyridine-2,3-dicarboxylic acid, urea, ammonium molybdate, copper chloride dihydrate and asphalt coke active carbon are mixed to obtain a mixture A; 2, the mixture A is kept at 100-180 DEG C, and then kept at 200-350 DEG C to obtain a product B; 3, the product B is ground, soaked, washed and dried in sequence to obtain pyridine nitrogen skeleton substituted phthalocyanine copper / asphalt coke active carbon; 4, phthalic anhydride, urea, ammonium molybdate, cobalt chloride hexahydrate and pyridine nitrogen skeleton substituted phthalocyanine copper / asphalt coke active carbon are mixed to obtain a mixture C; 5, the mixture C is kept at 100-180 DEG C, and then kept at 200-350 DEG C to obtain a product D; 6, the product D is ground, soaked, washed and dried in sequence to obtain the phthalocyanine cobalt / pyridine nitrogen skeleton substituted phthalocyanine copper / asphalt coke active carbon composite catalytic material, the purity of the material is high, and the discharge time and voltage of a Li / SOCl2 battery are improved.

Description

Technical Field

[0001] This invention relates to battery cathode catalytic materials, specifically to a cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalytic material, its preparation method, and its application. Background Technology

[0002] Lithium / thionyl chloride batteries possess a high specific capacity of 2300 mAh / g, a high energy density of 710 Wh / kg, and a high open-circuit voltage of 3.65 V. They exhibit an annual self-discharge rate of less than 1% and a storage life of up to 10 years. They can be used in a wide temperature range of -55℃ to 150℃. Especially when the ambient temperature is below -40℃, where many battery systems fail to function properly, lithium / thionyl chloride batteries still demonstrate excellent performance. Furthermore, lithium / thionyl chloride batteries have a high and stable discharge voltage, meeting the requirements of precision instruments for a high and stable voltage platform even during high current density discharge. Therefore, they have been widely used in aerospace, military, and intelligent instrumentation fields.

[0003] Lithium / thionyl chloride batteries use metallic lithium as the negative electrode, and the inorganic electrolyte LiAlCl4-SOCl2 serves as both the active material and the electrolyte. Carbon acts as the positive electrode. During discharge, metallic lithium reacts chemically with the electrolyte to produce LiCl and S products. When these discharge products clog the carbon electrode, the battery discharge stops. During discharge, the lithium negative electrode and the carbon positive electrode undergo the following reactions:

[0004] Positive electrode: 2SOCl2 + 4e - →S + SO₂ + 4Cl -

[0005] Negative electrode: Li-e - →Li +

[0006] Overall reaction: 4Li + 2SOCl₂ → SO₂↑ + S↓ + 4LiCl↓

[0007] In this process, SOCl2 at the positive electrode gains electrons and undergoes a reduction reaction to produce S, SO2, and Cl. - The lithium electrode at the negative electrode loses electrons to generate Li. + The ions migrate to the surface of the carbon cathode to form LiCl precipitate. As LiCl is formed, a dense LiCl film is formed on the carbon cathode. This LiCl film hinders the transport of electrons, the movement of ions and the diffusion of SOCl2, causing a significant decrease in the output power and energy of the battery.

[0008] Adding catalysts to the carbon cathode can effectively improve the performance of Li / SOCl2 batteries. However, most existing cathode catalysts, while accelerating the reduction rate of SOCl2, also exhibit strong adsorption of the reduction products S and LiCl, making it impossible to regulate the distribution of deposits in the cathode and electrode sheets. Phthalocyanine possesses a two-dimensional conjugated macrocyclic structure, with π electrons conjugated throughout the phthalocyanine ring. The four N atoms at the center of the structure provide favorable conditions for the insertion of metal atoms into the central hole. Most elements can form complexes with phthalocyanine, and it itself possesses good thermal and chemical stability. Studies have found that adding metal phthalocyanine complex catalysts to the carbon cathode can effectively regulate the growth of LiCl precipitates, thereby improving the performance of Li / SOCl2 batteries.

[0009] Currently, the main methods for preparing metal phthalocyanine complexes and their derivatives include solvothermal methods, microwave methods, and solid-phase methods. Among them, the solvothermal method has high yield and high purity, but it generates toxic and harmful byproducts during the reaction process; the microwave method has a fast reaction rate, but the yield is low; the solid-phase method generates a lot of free phthalocyanines during the preparation process, resulting in low purity of metal phthalocyanine complexes and their derivatives. Summary of the Invention

[0010] To address the shortcomings of existing technologies, the present invention aims to provide a cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalytic material, its preparation method, and its application. This improves the purity of the composite catalytic material, thereby increasing the discharge time and discharge voltage of lithium / thionyl chloride batteries.

[0011] To achieve the above objectives, the present invention employs the following technical solution:

[0012] A method for preparing a cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalytic material, characterized by comprising the following steps:

[0013] Step 1: Take 0.1-2.0g of pyridine-2,3-dicarboxylic acid, 0.15-3.0g of urea, 0.015-0.3g of ammonium molybdate, 0.05-1.1g of copper chloride dihydrate and 0.01-0.3g of pitch coke activated carbon, mix them evenly and grind them to obtain mixture A;

[0014] Step 2: Place mixture A in a muffle furnace and heat it from room temperature to 100-180°C at a heating rate of 5-10°C / min, hold it at that temperature for 0.5-1 h, then heat it to 200-350°C at a heating rate of 5-10°C / min, hold it at that temperature for 1-4 h, and then cool it naturally to room temperature to obtain product B.

[0015] Step 3: Grind, soak, wash and dry product B in sequence to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon;

[0016] Step 4: Take 0.1-2.0g phthalic anhydride, 0.15-3.0g urea, 0.015-0.3g ammonium molybdate, 0.08-1.5g cobalt chloride hexahydrate and 0.02-1.5g pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt activated carbon, mix them evenly and grind them to obtain mixture C;

[0017] Step 5: Place mixture C in a muffle furnace and heat it from room temperature to 100-180°C at a heating rate of 5-10°C / min, hold it at that temperature for 0.5-1 h, then heat it to 200-350°C at a heating rate of 5-10°C / min, hold it at that temperature for 1-4 h, and then cool it naturally to room temperature to obtain product D.

[0018] Step 6: Grind, soak, wash and dry product D sequentially to obtain cobalt phthalocyanine / pyridine nitrogen framework substituted copper phthalocyanine / asphalt coke activated carbon composite catalyst.

[0019] Furthermore, the soaking in steps 3 and 6 involves first soaking in deionized water for 8–24 hours, then discarding the supernatant, and repeating this process 3–4 times.

[0020] Furthermore, the cleaning in steps 3 and 6 involves alternating filtration and cleaning with deionized water and anhydrous ethanol 3 to 4 times.

[0021] Furthermore, the drying in steps 3 and 6 is carried out in a vacuum drying oven at 70–120°C for 10–28 hours.

[0022] A composite catalytic material of cobalt phthalocyanine / pyridine nitrogen framework substituted copper phthalocyanine / asphalt coke activated carbon.

[0023] Application of cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalyst as positive electrode catalyst for lithium / thionyl chloride batteries.

[0024] Compared with the prior art, the present invention has the following technical effects:

[0025] This invention employs a two-step solid-state method to prepare a cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalyst. In the first step, a pyridine nitrogen framework-substituted copper phthalocyanine is grown on the surface of activated carbon. In the second step, the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalyst is synthesized using the pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon synthesized in step 1 as raw material. This process requires only simple grinding, sintering, immersion purification, and drying. It is not only highly safe, simple to operate, low-cost, and environmentally friendly, but also achieves a yield of up to 60%, with a preparation cycle of only about 6 days. The prepared composite catalyst has high purity and can not only accelerate the reduction rate of SOCl2 during lithium / thionyl chloride battery discharge but also regulate the deposition of reduction products, thereby making the S distribution in the positive electrode and separator more uniform and improving the battery's discharge time and discharge voltage.

[0026] The CoPc central ion Co in the composite catalytic material prepared by this invention 2+ The electronic configuration is 3d 7 Besides strong coordination with N in the plane of phthalocyanine ligands, it can also undergo strong coordination adsorption with ligands (such as O in SOCl2) on its surface, exhibiting an octahedral configuration, thus accelerating the reduction reaction of SOCl2. Although Co 2+ For S and Cl in the product - Strong coordination adsorption also exists, which can cause S and LiCl to concentrate and deposit. However, the central ion has a 3d electronic configuration. 9 The copper phthalocyanine complex of divalent copper ions is difficult to react with S and Cl. - Coordination hinders the deposition of S and LiCl. Furthermore, by adding activated carbon support, the SOCl2 reaction rate and reduction product deposition can be regulated, resulting in a uniform distribution of S in the cathode and separator, increasing the number of reactive sites, and further improving battery performance. Attached Figure Description

[0027] Figure 1 The images show the Raman spectra of the catalytic materials prepared in Comparative Example 1, Comparative Example 2, and Examples 1 to 3.

[0028] Figure 2 The infrared spectra of the catalytic materials prepared in Comparative Example 1, Comparative Example 2, and Examples 1 to 3 are shown.

[0029] Figure 3(a) is a SEM image of the catalyst CuTAP / AC prepared in Comparative Example 1;

[0030] Figure 3(b) is a SEM image of the composite catalytic material CoPc / CuTAP / AC prepared in Example 1;

[0031] Figure 4The discharge curves of lithium / thionyl chloride batteries containing catalysts prepared in Comparative Example 1, Comparative Example 2, and Examples 1 to 3, respectively, are compared with those of lithium / thionyl chloride batteries without any catalysts.

[0032] Figure 5(a) shows the SEM image of the positive electrode and the EDS image of S in the positive electrode of the lithium / thionyl chloride battery containing the composite catalyst CoPc / CuTAP / AC prepared in Example 1 after discharge.

[0033] Figure 5(b) shows the SEM image of the positive electrode and the EDS image of S in the positive electrode after the lithium / thionyl chloride battery without any catalyst is discharged.

[0034] Figure 6 This is a schematic diagram of the molecular configuration of cobalt phthalocyanine and copper phthalocyanine with a pyridine nitrogen skeleton. Detailed Implementation

[0035] The specific content of the present invention will be further explained in detail below with reference to the embodiments.

[0036] Example 1

[0037] Step 1: Take 0.819g of pyridine-2,3-dicarboxylic acid, 1.2g of urea, 0.12g of ammonium molybdate, 0.435g of copper chloride dihydrate and 0.1g of pitch coke activated carbon, put them into an agate mortar, mix them evenly and grind them to obtain mixture A;

[0038] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 0.5 h. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 h. Allow it to cool naturally to room temperature to obtain product B.

[0039] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, soak the collected product B for 24h, and after the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24h to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon.

[0040] Step 4: Take 0.819g of phthalic anhydride, 1.2g of urea, 0.12g of ammonium molybdate, 0.606g of cobalt chloride hexahydrate and 0.14g of pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon and put them into an agate mortar, mix and grind evenly to obtain mixture C;

[0041] Step 5: Place mixture C into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 1 hour. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 hours. Allow it to cool naturally to room temperature to obtain product D.

[0042] Step 6: First, collect product D and grind it until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, and soak the collected product D for 24h. After the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 4 times by alternating filtration with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24h to obtain the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt coke activated carbon composite catalyst, denoted as CoPc / CuTAP / AC 3:1.

[0043] Example 2

[0044] Step 1: Take 0.819g of pyridine-2,3-dicarboxylic acid, 1.2g of urea, 0.12g of ammonium molybdate, 0.435g of copper chloride dihydrate and 0.1g of pitch coke activated carbon, put them into an agate mortar, mix them evenly and grind them to obtain mixture A;

[0045] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 0.5 h. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 h. Allow it to cool naturally to room temperature to obtain product B.

[0046] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, soak the collected product B for 24h, and after the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24h to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon.

[0047] Step 4: Take 0.819g of phthalic anhydride, 1.2g of urea, 0.12g of ammonium molybdate, 0.606g of cobalt chloride hexahydrate and 0.42g of pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon and put them into an agate mortar, mix and grind evenly to obtain mixture C;

[0048] Step 5: Place mixture C into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 1 hour. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 hours. Allow it to cool naturally to room temperature to obtain product D.

[0049] Step 6: First, collect product D and grind it until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, and soak the collected product D for 24h. After the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24h to obtain the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt coke activated carbon composite catalyst, denoted as CoPc / CuTAP / AC 1:1.

[0050] Example 3

[0051] Step 1: Take 0.819g of pyridine-2,3-dicarboxylic acid, 1.2g of urea, 0.12g of ammonium molybdate, 0.435g of copper chloride dihydrate and 0.1g of pitch coke activated carbon, put them into an agate mortar, mix them evenly and grind them to obtain mixture A;

[0052] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 0.5 h. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 h. Allow it to cool naturally to room temperature to obtain product B.

[0053] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, soak the collected product B for 24h, and after the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24h to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon.

[0054] Step 4: Take 0.819g of phthalic anhydride, 1.2g of urea, 0.12g of ammonium molybdate, 0.606g of cobalt chloride hexahydrate and 1.2g of pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon and put them into an agate mortar, mix and grind evenly to obtain mixture C;

[0055] Step 5: Place mixture C into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 1 hour. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 hours. Allow it to cool naturally to room temperature to obtain product D.

[0056] Step 6: First, collect product D and grind it until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, and soak the collected product D for 24h. After the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24h to obtain the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt coke activated carbon composite catalyst, denoted as CoPc / CuTAP / AC 1:3.

[0057] Example 4

[0058] Step 1: Take 0.1g of pyridine-2,3-dicarboxylic acid, 0.15g of urea, 0.015g of ammonium molybdate, 0.05g of copper chloride dihydrate and 0.01g of pitch coke activated carbon, put them into an agate mortar, mix them evenly and grind them to obtain mixture A;

[0059] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 100°C at a heating rate of 5°C / min and hold for 1 hour. Then heat the mixture to 200°C at a heating rate of 5°C / min and hold for 4 hours. Allow it to cool naturally to room temperature to obtain product B.

[0060] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, soak the collected product B for 8 hours, and after the solid particles have completely precipitated, discard the supernatant. Repeat this process 3 times. Then, wash the product 3 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 70℃ for 28 hours to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon.

[0061] Step 4: Take 0.1g phthalic anhydride, 0.15g urea, 0.015g ammonium molybdate, 0.08g cobalt chloride hexahydrate and 0.02g pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon and put them into an agate mortar, mix and grind evenly to obtain mixture C;

[0062] Step 5: Place mixture C into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 100°C at a heating rate of 5°C / min, hold for 0.5 h, then heat the mixture to 200°C at a heating rate of 5°C / min, hold for 4 h, and allow it to cool naturally to room temperature to obtain product D.

[0063] Step 6: First, collect product D and grind it until the particles are fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water, and soak product D for 8 hours. After the solid particles have completely precipitated, discard the supernatant. Repeat this process three times. Then, wash the product three times by alternating filtration with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 70℃ for 28 hours to obtain a cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalyst, denoted as CoPc / CuTAP / AC 1:4.

[0064] Example 5

[0065] Step 1: Take 2.0g of pyridine-2,3-dicarboxylic acid, 3.0g of urea, 0.3g of ammonium molybdate, 1.1g of copper chloride dihydrate and 0.3g of pitch coke activated carbon, put them into an agate mortar, mix them evenly and grind them to obtain mixture A;

[0066] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 140°C at a heating rate of 7°C / min and hold for 1 hour. Then heat the mixture to 350°C at a heating rate of 7°C / min and hold for 1 hour. Allow it to cool naturally to room temperature to obtain product B.

[0067] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, soak the collected product B for 20h, and after the solid particles have completely precipitated, discard the supernatant. Repeat this process 3 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 120℃ for 10h to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon.

[0068] Step 4: Take 2.0g of phthalic anhydride, 3.0g of urea, 0.3g of ammonium molybdate, 1.5g of cobalt chloride hexahydrate and 1.5g of pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon and put them into an agate mortar, mix and grind evenly to obtain mixture C;

[0069] Step 5: Place mixture C into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 140°C at a heating rate of 7°C / min, hold for 0.5 h, then heat it to 350°C at a heating rate of 7°C / min, hold for 1 h, and allow it to cool naturally to room temperature to obtain product D.

[0070] Step 6: First, collect product D and grind it until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, and soak the collected product D for 20h. After the solid particles have completely precipitated, discard the supernatant. Repeat this process 3 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 120℃ for 10h to obtain the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt coke activated carbon composite catalyst, denoted as CoPc / CuTAP / AC2:3.

[0071] Example 6

[0072] Step 1: Take 1.05g of pyridine-2,3-dicarboxylic acid, 1.6g of urea, 0.16g of ammonium molybdate, 0.58g of copper chloride dihydrate and 0.16g of pitch coke activated carbon, put them into an agate mortar, mix them evenly and grind them to obtain mixture A;

[0073] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 160°C at a heating rate of 8°C / min and hold for 1 hour. Then heat the mixture to 300°C at a heating rate of 8°C / min and hold for 3 hours. Allow it to cool naturally to room temperature to obtain product B.

[0074] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, soak the collected product B for 16h, and after the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 3 times by alternating filtration with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 100℃ for 18h to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon.

[0075] Step 4: Take 1.05g of phthalic anhydride, 1.6g of urea, 0.16g of ammonium molybdate, 0.79g of cobalt chloride hexahydrate and 0.8g of pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon and put them into an agate mortar, mix and grind evenly to obtain mixture C;

[0076] Step 5: Place mixture C into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 160°C at a heating rate of 8°C / min, hold for 0.5 h, then heat the mixture to 300°C at a heating rate of 8°C / min, hold for 3 h, and allow it to cool naturally to room temperature to obtain product D.

[0077] Step 6: First, collect product D and grind it until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, and soak the collected product D for 16h. After the solid particles have completely precipitated, discard the supernatant. Repeat this process 4 times. Then, wash the product 3 times by alternating filtration with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 100℃ for 18h to obtain the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt coke activated carbon composite catalyst material, denoted as CoPc / CuTAP / AC2:3.

[0078] Comparative Example 1

[0079] Step 1: Take 0.819g of pyridine-2,3-dicarboxylic acid, 1.2g of urea, 0.12g of ammonium molybdate, 0.435g of copper chloride dihydrate and 0.1g of pitch coke activated carbon, put them into an agate mortar, mix and grind evenly to obtain mixture A;

[0080] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 1 hour. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 hours. Allow it to cool naturally to room temperature to obtain product B.

[0081] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, and soak the collected product B for 24 hours. After the solid particles have completely precipitated, discard the supernatant and repeat the operation 4 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24 hours and grind it to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon, denoted as CuTAP / AC.

[0082] Comparative Example 2

[0083] Step 1: Take 0.819g of phthalic anhydride, 1.2g of urea, 0.12g of ammonium molybdate, and 0.607g of cobalt chloride hexahydrate, put them into an agate mortar, mix and grind them evenly to obtain mixture A;

[0084] Step 2: Place mixture A into a porcelain crucible and place it in a muffle furnace. Heat the mixture from room temperature to 180°C at a heating rate of 10°C / min and hold for 1 hour. Then heat the mixture to 270°C at a heating rate of 10°C / min and hold for 2 hours. Allow it to cool naturally to room temperature to obtain product B.

[0085] Step 3: First, scrape product B from the wall of the porcelain crucible and grind it in an agate mortar until the particles become fine. Then, transfer it to a 500mL beaker, add 400mL of deionized water to the beaker, and soak the collected product B for 24 hours. After the solid particles have completely precipitated, discard the supernatant. Repeat the operation 4 times. Then, wash the product 4 times by alternately filtering with deionized water and anhydrous ethanol. Finally, dry the product in a vacuum drying oven at 80℃ for 24 hours, grind it, and obtain the cobalt phthalocyanine catalyst material, denoted as CoPc.

[0086] from Figure 1 It can be seen that the CoPc / CuTAP / AC prepared in Examples 1 to 3 have different values ​​of 729, 1086, 1121, 1290, 1329, 1420, 1520, 1593 and 1639 cm⁻¹, respectively. -1 Significant absorption peaks are observed at these locations, corresponding to vibrations in the CoPc and CuTAP molecular backbones, particularly at 729 cm⁻¹. -1 and 1086cm -1 The peak positions are attributed to the characteristic vibrations of CoPc and CuTAP, respectively, while the 1121 cm⁻¹ peak position is... -1 The peak position is related to the vibration of the coordinated nitrogen atom in CoPc. Furthermore, at 1420 cm⁻¹... -1 The absorption peak at 1425 cm⁻¹ can be explained by the interaction between CoPc and CuTAP / AC, where the peak originally located at 1425 cm⁻¹ was shifted. -1 and 1394cm -1 The peak positions merged, proving that Examples 1-3 successfully synthesized the CoPc / CuTAP / AC composite catalyst with a cobalt phthalocyanine / pyridine nitrogen framework substituted copper phthalocyanine / asphalt coke activated carbon.

[0087] from Figure 2 It can be seen that CoPc is at 598, 683, 752, and 1142 cm⁻¹ -1 The peak values ​​appearing at [values] and the relationship between CoPc and CuTAP / AC at 832, 937, 1142, 1340, and 1537 cm⁻¹. -1 The peak values ​​appearing at the specified locations all indicate the interaction between CoPc and CuTAP / AC, further demonstrating that Examples 1-3 successfully synthesized the CoPc / CuTAP / AC composite catalytic material with a cobalt phthalocyanine / pyridine nitrogen framework substituted for copper phthalocyanine / asphalt activated carbon.

[0088] As shown in Figure 3(a), the CuTAP block in the catalytic material CuTAP / AC prepared in Comparative Example 1 has a particle size of about 4 μm. As shown in Figure 3(b), the CuTAP block in the composite catalytic material CoPc / CuTAP / AC prepared in Example 1 has a particle size of about 2 μm. The CoPc composite on it is refined into small particles with a particle size distribution in the range of tens of nanometers, which increases the specific surface area of ​​CoPc and CuTAP, fully exposes the active sites, thereby improving the reduction rate of thionyl chloride and effectively controlling the distribution of reduction products.

[0089] To verify the effects of CoPc and CuTAP / AC content on battery discharge time and voltage, Examples 1-3 used identical process parameters to prepare composite catalysts CoPc / CoTAP / CuPc 3:1, CoPc / CoTAP / CuPc 1:1, and CoPc / CoTAP / CuPc 1:3, respectively. Meanwhile, Comparative Examples 1 and 2 prepared catalysts CuTAP / AC and CoPc, respectively. The catalysts prepared in Comparative Examples 1, 2, and Examples 1-3 were then added to the positive electrode of lithium / thionyl chloride batteries, and lithium / thionyl chloride batteries were assembled and their performance tested. A lithium / thionyl chloride battery without added catalyst was used as a control group, labeled "bare." The results are as follows: Figure 4 As shown, without the addition of a catalyst, the initial discharge voltage of the battery was 2.8V, and the discharge process lasted for 18 minutes. After adding the catalyst CoPc prepared in Comparative Example 2, the discharge voltage of the battery increased to 3.08V, but the discharge time did not increase significantly, indicating that CoPc can improve the discharge voltage of the battery. After adding the catalyst CuTAP / AC prepared in Comparative Example 1, the discharge voltage of the battery did not change significantly, but the discharge time was extended to 28 minutes, indicating that the catalyst CuTAP / AC can improve the discharge time of the battery. For lithium / thionyl chloride batteries with the addition of composite catalysts CoPc / CoTAP / CuPc 1:3, CoPc / CoTAP / CuPc 1:1, and CoPc / CoTAP / CuPc 3:1, the discharge voltage gradually increased with the increase of the CoPc ratio, and the discharge time also increased. In particular, after adding CoPc / CoTAP / CuPc 3:1 prepared in Example 1, that is, when the ratio of CoPc to CuTAP / AC is 3:1, both the discharge voltage and discharge time are optimal.

[0090] The deposition distribution of S was measured by EDS on the positive electrode sheet prepared in Example 1 with CoPc / CoTAP / CuPc 3:1 after discharge. The results are shown in Figure 5(a). It can be seen that the reduction product S generated by the decomposition of thionyl chloride SOCl2 is distributed very uniformly on the surface of the carbon positive electrode. This indicates that the catalyst CoPc / CoTAP / CuPc effectively regulates the formation and deposition process of the reduction product, avoids excessive local accumulation, and thus promotes the uniform utilization of electrochemical active materials on the entire electrode surface.

[0091] EDS tests were performed on the deposition distribution of sulfur on the uncatalyst-free positive electrode after discharge. The results are shown in Figure 5(b). It can be seen that the deposition of sulfur on the carbon positive electrode is very uneven without the addition of any catalyst. Dense sulfur deposition was observed in some areas, while sulfur was almost invisible in other areas. This phenomenon leads to unstable battery performance and low efficiency.

[0092] from Figure 6 It can be seen that the central metal ion Co of CoPc is... 2+ CoPc forms a relatively stable octahedral configuration when combined with macrocyclic phthalocyanines. During the reduction of SOCl2, the interaction between CoPc and SOCl2 mainly involves the formation of coordination bonds between the central metal ion and the O atoms of SOCl2, as well as various van der Waals forces. Due to its strong adsorption properties, the product LiCl generated during battery discharge is densely packed inside the electrode. However, for CuTAP, because Cu... 2+ Cu has 9 outer electrons and its orbital splitting energy is relatively large, therefore Cu 2+ The d orbital filling will become t 2g 6 e g 3 , where e g The orbital distribution is (d z2 ) 1 (d x2-y2 ) 2 This causes the energy levels of bond length shortening on the x and y planes to increase, while the energy levels of bond length elongation on the z-axis to decrease, thus eliminating the e g (d z2， d x2-y2 The degeneracy of CuTAP results in four coplanar short bonds and two long bonds perpendicular to the plane, leading to the Gaindale distortion and a slender octahedral configuration. Furthermore, CuTAP has a coordination number of 4. Due to the Gaindale distortion, the planar geometry of CuTAP is distorted into a square. During the reduction of SOCl2, the Cu in CuTAP... 2+It is difficult for CuTAP to form coordinate bonds with the O atoms of SOCl2, so the bond between CuTAP and SOCl2 can only be maintained by some van der Waals forces. The bond between the two is relatively weak, thus enabling efficient transport of reaction products LiCl and S.

Claims

1. A method for preparing a cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalytic material, characterized in that, Includes the following steps: Step 1: Take 0.1-2.0g of pyridine-2,3-dicarboxylic acid, 0.15-3.0g of urea, 0.015-0.3g of ammonium molybdate, 0.05-1.1g of copper chloride dihydrate and 0.01-0.3g of pitch coke activated carbon, mix them evenly and grind them to obtain mixture A; Step 2: Place mixture A in a muffle furnace and heat it from room temperature to 100-180°C at a heating rate of 5-10°C / min, hold it at that temperature for 0.5-1 h, then heat it to 200-350°C at a heating rate of 5-10°C / min, hold it at that temperature for 1-4 h, and then cool it naturally to room temperature to obtain product B. Step 3: Grind, soak, wash and dry product B in sequence to obtain pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt coke activated carbon; Step 4: Take 0.1-2.0g phthalic anhydride, 0.15-3.0g urea, 0.015-0.3g ammonium molybdate, 0.08-1.5g cobalt chloride hexahydrate and 0.02-1.5g pyridine nitrogen skeleton substituted copper phthalocyanine / asphalt activated carbon, mix them evenly and grind them to obtain mixture C; Step 5: Place mixture C in a muffle furnace and heat it from room temperature to 100-180°C at a heating rate of 5-10°C / min, hold it at that temperature for 0.5-1 h, then heat it to 200-350°C at a heating rate of 5-10°C / min, hold it at that temperature for 1-4 h, and then cool it naturally to room temperature to obtain product D. Step 6: Grind, soak, wash and dry product D sequentially to obtain cobalt phthalocyanine / pyridine nitrogen framework substituted copper phthalocyanine / asphalt coke activated carbon composite catalyst.

2. The preparation method of the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalytic material according to claim 1, characterized in that, The soaking process in steps 3 and 6 involves first soaking in deionized water for 8–24 hours, then discarding the supernatant, and repeating this process 3–4 times.

3. The preparation method of the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalytic material according to claim 1, characterized in that, The cleaning in steps 3 and 6 involves alternating filtration and cleaning with deionized water and anhydrous ethanol 3 to 4 times.

4. The preparation method of the cobalt phthalocyanine / pyridine nitrogen framework-substituted copper phthalocyanine / asphalt activated carbon composite catalytic material according to claim 1, characterized in that, The drying in steps 3 and 6 is carried out in a vacuum drying oven at 70–120°C for 10–28 hours.

5. A phthalocyanine cobalt / pyridine nitrogen framework substituted phthalocyanine copper / asphalt coke activated carbon composite catalytic material prepared by the method according to any one of claims 1 to 4.

6. The application of the cobalt phthalocyanine / pyridine nitrogen skeleton-substituted copper phthalocyanine / asphalt activated carbon composite catalyst according to claim 5 as a cathode catalyst for lithium / thionyl chloride batteries.

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