A porphyrin COF material, its preparation method and application

Abstract

The present invention discloses a porphyrin COF material, its preparation method and application, belonging to the technical field of preparation of wastewater treatment materials. The preparation method disclosed by the present invention comprises the following steps: S1: reacting tetracarboxyl porphyrin, ferric salt and a solvent under reflux conditions, and after the reaction is completed, post-treating the obtained reaction product to obtain Fe<supgt;3+< / supgt>-TCPP solid; S2: reacting the Fe<supgt;3+< / supgt>-TCPP solid, an acyl chlorination reagent and a solvent under reflux conditions, and after the reaction is completed, post-treating the obtained reaction product to obtain Fe<supgt;3+< / supgt>-TCPP-COCl solid; S3: grinding and reacting the Fe<supgt;3+< / supgt>-TCPP-COCl solid with p-phenylenediamine, and after the reaction is completed, post-treating the obtained reaction product to obtain the porphyrin COF material; this method overcomes the limitations of the traditional preparation method.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of wastewater treatment materials, and particularly relates to a porphyrin COF material, a preparation method thereof, and an application thereof. Background Art

[0002] With the booming development of the chemical, pharmaceutical, and agricultural industries, the pollution of water environment by organic synthetic compounds has become an increasingly serious problem, far exceeding the self-purification function of natural water bodies. These complex, toxic, and difficult-to-decompose organic pollutants, including organic dyes, phenol and its derivatives, antibiotics, surfactants, and pesticides, etc., seriously threaten the ecosystem and sustainable development. Therefore, controlling and remediating wastewater pollution, especially treating organic pollutants in wastewater, has become a focus issue of global concern. This is not only crucial for improving the quality of the aquatic ecosystem but also can bring significant economic benefits.

[0003] At present, the methods for treating organic pollutants in water mainly include extraction method, biodegradation method, adsorption method, ozone oxidation method, ionizing radiation method, Fenton oxidation method, photocatalysis method, and persulfate (PDS) activation method, etc. Although the above methods have effective treatment capabilities for organic pollutants at the laboratory level, there are certain limitations in practical applications [Chemosphere, 2022, 286 131646]. For example, the extraction method is rapid and simple, but it requires a large amount of organic solvents, which may cause secondary pollution. The biodegradation method is environmentally friendly and mild, but it has a long treatment time, large floor area, high energy consumption, and limited treatment capacity. The adsorption method faces the problems of easy saturation of the adsorbent and difficulty in regenerating or replacing the adsorbent. The ozone oxidation method has strong oxidation ability and simple operation, but the investment and operation costs are relatively high. The ionizing radiation method is effective, but the operation process is complex. The Fenton oxidation method can oxidize most organic substances in water, but it is costly and may cause greater negative impacts on the environment. Although the photocatalysis method can completely convert organic pollutants into non-toxic inorganic substances under mild conditions, it faces problems such as low solar energy utilization rate, difficult separation of catalysts, poor catalytic stability, and low mineralization rate in applications [Science of the Total Environment, 2022, 812, 152434]. The PDS activation method has good degradation performance, but there are still a series of challenges in its application. For example, external energy input is required for the activation processes of ultraviolet light, electricity, heat, and ultrasonic waves. For transition metal activation, if homogeneous metal ions are used, their activation effect highly depends on the pH value, which may lead to the formation of precipitates and require additional treatment steps. In addition, some metal ions are toxic and may cause secondary environmental pollution after treatment. If heterogeneous metal catalysts, especially nanoparticle catalysts, are used, problems such as metal leaching and aggregation may occur, thus reducing the catalytic efficiency [Coordination Chemistry Reviews, 499 (2024), 215466].

[0004] The current covalent organic framework (COF) materials have attracted attention due to their high specific surface area and adjustable pore structure, but there are some disadvantages: many materials have single functions and lack multifunctionality; the synthesis process is complex and it is difficult to produce on a large scale; the functionalization is difficult and the adaptability is insufficient, especially for the complete degradation of organic pollutants in water. These problems limit the effectiveness of existing COF materials in practical applications, and it is urgent to develop more advanced and multifunctional COF materials to meet the needs. Summary of the Invention

[0005] The purpose of the present invention is to provide a porphyrin COF material, its preparation method and application, so as to solve the technical problem that the existing COF materials have poor effect in degrading organic pollutants in water due to single functions.

[0006] To achieve the above object, the present invention is implemented by the following technical solutions:

[0007] The present invention discloses a preparation method of a porphyrin COF material, comprising the following steps:

[0008] S1: React tetracarboxyporphyrin, ferric salt and a solvent under reflux conditions. After the reaction is completed, post-treat the obtained reaction product to obtain Fe 3+ -TCPP solid;

[0009] S2: React the Fe 3+ -TCPP solid, an acyl chlorination reagent and a solvent under reflux conditions. After the reaction is completed, post-treat the obtained reaction product to obtain Fe 3+ -TCPP-COCl solid;

[0010] S3: Grind and react the Fe 3+ -TCPP-COCl solid and p-phenylenediamine. After the reaction is completed, post-treat the obtained reaction product to obtain the porphyrin COF material.

[0011] Further, in S1, the dosage ratio of the tetracarboxyporphyrin, ferric salt and the solvent is 1 mol:(1.25 - 1.5) mol:50 mL; the solvent is a mixture of CHCl3 and DMF with a volume ratio of (4 - 6):1;

[0012] The tetracarboxyporphyrin is 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin;

[0013] The ferric salt is Fe2S3O 12 ·9H2O.

[0014] Further, in S1, the parameters of the reflux conditions are: the reflux temperature is 130 - 140 °C, and the reflux time is 3 - 5 h.

[0015] Further, in S1, the post-treatment includes distillation, filtration and washing treatments carried out in sequence; the temperature of the distillation is 70 - 72 °C; the filtration is carried out under normal pressure; the washing treatment is to wash 3 - 5 times each with methanol and deionized water.

[0016] Further, in S2, the molar ratio of the Fe 3+ -TCPP solid and the acyl chlorination reagent is 1:(5 - 8);

[0017] The solvent is CH2ClCH2Cl; the volume ratio of the acyl chlorination reagent and the solvent is 1:(6 - 8);

[0018] The acylating reagent is one of SOCl2, PCl5 and PCl3;

[0019] The parameters of the reflux condition are: the reflux temperature is 83 - 85 °C, and the reflux time is 2 - 4 h.

[0020] Further, in S2, the post-treatment includes filtration and washing treatments carried out in sequence; the filtration is carried out under normal pressure; the washing treatment is to wash 3 - 5 times each with methanol and deionized water.

[0021] Further, in S3, the Fe 3+ -TCPP-COCl solid and p-phenylenediamine have a molar ratio of 1:(2 - 2.5); the grinding is carried out at room temperature for 20 - 40 min.

[0022] Further, in S3, the post-treatment includes washing and drying treatments carried out in sequence; the washing is to wash 3 - 5 times each with ethanol and deionized water; the temperature of the drying treatment is 105 - 115 °C, and the time is 6 - 8 h.

[0023] The present invention also discloses a porphyrin COF material prepared by the above preparation method.

[0024] The present invention also discloses the application of the above porphyrin COF material in the degradation of organic pollutants in water.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention discloses a preparation method of a porphyrin COF material. By reasonably selecting tetracarboxyl porphyrin and ferric salt as raw materials and carrying out the reaction under reflux conditions, and by optimizing the reaction parameters and post-treatment steps, the purity and yield of the prepared porphyrin COF material are improved; the preparation method disclosed in the present invention adopts a stepwise reaction path method to gradually introduce functional groups to ensure the structural integrity and multifunctionality of the porphyrin COF material. In particular, Fe³⁺ ions are introduced through ferric salt, and combined with the rest of the raw materials, the photocatalytic and PDS activation performances of the porphyrin COF material are significantly enhanced, and a multifunctional porphyrin COF material with adsorption, photocatalysis and PDS activation can be prepared; compared with the prior art, the present invention overcomes the limitations of traditional preparation methods and solves the technical problem that the existing COF materials have poor effects in degrading organic pollutants in water due to single function.

[0027] Furthermore, the dosage ratio of tetracarboxyl porphyrin, ferric salt and solvent is 1 mol : (1.25 - 1.5) mol : 50 mL, which helps to optimize the reaction conditions, ensure the high efficiency of the reaction and the purity of the product; using a mixture of CHCl3 and DMF as the solvent not only improves the solubility of the reactants but also helps to improve the quality of the product; using 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin as the raw material has good optical properties and catalytic activity, improving the performance of the final porphyrin COF material; using Fe2S3O 12 ·9H2O as the raw material, which is cheap and easily available.

[0028] Furthermore, when preparing Fe 3+ -TCPP solid, the reflux temperature is set at 130 - 140 °C and the reflux time is 3 - 5 h, which reduces the possibility of side reactions, ensures the full conversion of reactants into the target product, thereby improving the selectivity of the product and the yield of the product.

[0029] Furthermore, when preparing Fe 3+ -TCPP solid, distillation, filtration and washing treatments are carried out in sequence to ensure the purity of the reaction product and remove unreacted raw materials and impurities; the clear regulations on the distillation temperature and the number of washing treatments help to obtain high-purity Fe 3+ -TCPP solid, further improving the efficiency and effect of subsequent reactions.

[0030] Furthermore, when preparing Fe 3+ -TCPP-COCl solid, the molar ratio of Fe 3+ -TCPP solid to the acyl chlorination reagent and the reflux conditions are fixed to ensure the high efficiency and selectivity of the reaction, reducing the generation of by-products; at the same time, the diverse selection of acyl chlorination reagents provides flexibility, enabling the reaction to be optimized under different conditions.

[0031] Furthermore, when preparing Fe 3+ -TCPP-COCl solid, filtration and washing treatments are carried out in sequence, making the whole process more efficient and capable of effectively removing impurities; filtering under normal pressure, combined with washing with methanol and deionized water, improves the purity of the product and reduces the residue of potential pollutants.

[0032] Furthermore, Fe 3+- The molar ratio of -TCPP-COCl solid to p-phenylenediamine is 1:(2 - 2.5), which helps to optimize the reaction efficiency and ensure the quality of the final product; controlling the grinding time within 20 - 40 min can effectively promote the reaction while avoiding material loss or product denaturation caused by over-grinding; in the step of preparing the porphyrin COF material, washing and drying treatments are carried out successively, which helps to remove unreacted raw materials and by-products, thereby improving the quality of the final product; adopting the regulation of washing 3 - 5 times with ethanol and deionized water respectively can effectively remove surface-adsorbed impurities and solvent residues, ensuring the purity of the material and improving its catalytic performance; setting the drying temperature at 105 - 115 °C and the drying time at 6 - 8 h ensures that the material can remove moisture without being damaged in structure or changed in physical properties due to high temperature.

[0033] The present invention also discloses a porphyrin COF material prepared by the above method. Its stable metal porphyrin structure ensures the chemical stability of the porphyrin COF material during multiple uses, reducing the replacement frequency and improving economic benefits; in addition, the present invention adopts a synthesis strategy of stepwise reaction, and the material formula used in the reaction is adjustable, facilitating customization for specific applications; the prepared porphyrin COF material has multiple functions of adsorption, photocatalysis and PDS activation, is suitable for the fields of environmental governance and renewable energy, and shows good application potential in the fields of water treatment and photocatalysis, etc. Description of the Drawings

[0034] Figure 1 It is the SEM (scanning electron microscope) image of the porphyrin COF material prepared in Example 3 of the present invention;

[0035] Figure 2 It is the elemental spot-scanning image of the porphyrin COF material prepared in Example 3 of the present invention;

[0036] Among them: a) - Overall SEM image; b) - C element distribution map; c) - N element distribution map; d) - O element distribution map; e) - Fe element distribution map;

[0037] Figure 3 It is the infrared spectrum of the porphyrin COF material prepared in Example 3 of the present invention;

[0038] Figure 4 It is the PXRD (powder X-ray diffraction) pattern of the porphyrin COF material prepared in Example 3 of the present invention;

[0039] Figure 5 It is the XPS (X-ray photoelectron spectroscopy) spectrum of the porphyrin COF material prepared in Example 3 of the present invention;

[0040] Among them: (a) - XPS survey spectrum; (b) - XPS fine spectrum of C; (c) - XPS fine spectrum of N; (d) - XPS fine spectrum of O; (e) - XPS fine spectrum of Fe;

[0041] Figure 6 It is the thermal stability diagram of the porphyrin COF material prepared in Example 3 of the present invention;

[0042] Figure 7 It is the nitrogen adsorption - desorption experimental data diagram of the porphyrin COF material prepared in Example 3 of the present invention;

[0043] Figure 8 It is the UV - Vis diffuse reflectance spectrum of the porphyrin COF material prepared in Example 3 of the present invention;

[0044] Among them: (a), UV - Vis diffuse reflectance spectrum; (b), the diagram for obtaining the band gap of the material. Detailed implementation manners

[0045] To enable those skilled in the art to understand the features and effects of the present invention, the following provides a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used herein shall have the ordinary meaning understood by those skilled in the art regarding the present invention. In case of conflict, the definition in this specification shall prevail.

[0046] The theories or mechanisms described and disclosed herein, whether correct or incorrect, shall not limit the scope of the present invention in any way, that is, the content of the present invention can be implemented without being limited by any specific theory or mechanism.

[0047] In this article, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are only for the sake of brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be regarded as having covered and specifically disclosed all possible sub - ranges and individual values within the range (including integers and fractions).

[0048] In this article, unless otherwise specified, "comprising", "including", "containing", "having" or similar expressions cover the meanings of "consisting of" and "consisting essentially of". For example, "A comprises a" covers the meanings of "A comprises a and others" and "A only comprises a".

[0049] In this article, for the sake of concise description, all possible combinations of all technical features in each embodiment or example are not described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered as being within the scope described in this specification.

[0050] The present invention provides a preparation method of a porphyrin COF material, comprising the following steps:

[0051] S1: React tetracarboxyporphyrin, ferric salt and a solvent under reflux conditions. After the reaction ends and the temperature drops to room temperature, the obtained reaction product is successively subjected to distillation, filtration and washing treatments to obtain Fe 3+ -TCPP solid;

[0052] S2: React the Fe 3+ -TCPP solid, an acyl chlorination reagent and a solvent under reflux conditions. After the reaction ends and the temperature drops to room temperature, the obtained reaction product is successively subjected to filtration and washing treatments to obtain Fe 3+ -TCPP-COCl solid;

[0053] S3: Grind and react the Fe 3+ -TCPP-COCl solid and p-phenylenediamine (PD) at room temperature. After the reaction ends, the obtained reaction product is successively subjected to washing and drying treatments to obtain a porphyrin COF material (Fe 3+ -Por-COF).

[0054] Preferably, in S1, the dosage ratio of the tetracarboxyporphyrin, ferric salt and solvent is 1 mol:(1.25 - 1.5) mol:50 mL; the solvent is a mixture of CHCl3 (chloroform) and DMF (dimethylformamide) with a volume ratio of (4 - 6):1; the parameters of the reflux conditions are: the reflux temperature is 130 - 140 °C, and the reflux time is 3 - 5 h; the temperature of the distillation is 70 - 72 °C; the filtration is carried out under normal pressure; the washing treatment is to wash 3 - 5 times each with methanol and deionized water.

[0055] Preferably, in S1, the tetracarboxyporphyrin is 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin; the ferric salt is Fe2S3O 12 ·9H2O.

[0056] Preferably, in S2, the molar ratio of the Fe 3+ -TCPP solid and the acyl chlorination reagent is 1:(5 - 8); the volume ratio of the acyl chlorination reagent and the solvent is 1:(6 - 8); the parameters of the reflux conditions are: the reflux temperature is 83 - 85 °C, and the reflux time is 2 - 4 h; the solvent is CH2ClCH2Cl (1,2-dichloroethane); the acyl chlorination reagent is one of SOCl2, PCl5 and PCl3; the filtration is carried out under normal pressure; the washing treatment is to wash 3 - 5 times each with methanol and deionized water.

[0057] Preferably, in S3, the Fe 3+-The molar ratio of -TCPP-COCl solid to p-phenylenediamine is 1:(2 - 2.5); the grinding is carried out at room temperature for 20 - 40 min; the washing is carried out 3 - 5 times each with ethanol and deionized water; the temperature for the drying treatment is 105 - 115 °C and the time is 6 - 8 h.

[0058] In S1, when the tetracarboxyl porphyrin is 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) and the ferric salt is ferric sulfate (Fe2(SO4)3∙9H2O), Fe 3+ -TCPP solid reacts as shown in the following formula:

[0059] ;

[0060] Since ferric ions are generated after Fe2(SO4)3∙9H2O dissolves, and the four nitrogens in the porphyrin center of TCPP have good coordination ability, under reflux conditions, the ferric ions will gradually undergo a coordination reaction with the four nitrogens in the porphyrin center to form ferric porphyrin (Fe 3+ -TCPP solid); due to the strong coordination relationship of the coordination reaction, the ferric ions will not fall off and agglomerate randomly during the use of the porphyrin COF material, which reduces the possibility of secondary pollution.

[0061] In S2, when the acyl chlorination reagent is thionyl dichloride (SOCl2), Fe 3+ -TCPP-COCl solid reacts as shown in the following formula:

[0062] ;

[0063] Fe 3+ -TCPP solid and SOCl2 undergo an acyl chlorination reaction, converting the carboxyl group in Fe 3+ -TCPP solid into an acyl chloride group to form acyl chlorinated ferric porphyrin (Fe 3+ -TCPP-COCl solid).

[0064] In S3, the reaction process to obtain Fe 3+ -Por-COF (porphyrin COF material) is shown in the following formula:

[0065] ;

[0066] Fe 3+ -The acyl chloride group in -TCPP-COCl solid will undergo a polycondensation reaction with the amino group in PD to generate Fe 3+ -Por-COF and HCl.

[0067] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0068] In the following examples, conventional instrument equipment in the art is used. For the experimental methods without specific conditions noted in the following examples, they are usually carried out under conventional conditions or according to the conditions recommended by the manufacturer. Various raw materials are used in the following examples. Unless otherwise stated, conventional commercially available products are used, and their specifications are the conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" represents weight percentage, "parts" represents weight parts, and the ratio represents weight ratio.

[0069] Example 1

[0070] A preparation method of a porphyrin COF material, comprising the following steps:

[0071] Step 1: React 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin, Fe2S3O 12 ·9H2O and a solvent under reflux conditions. After the reaction is completed and the temperature is lowered to room temperature, the obtained reaction product is successively subjected to distillation, filtration and washing treatments to obtain Fe 3+ -TCPP solid; wherein, the molar ratio of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin to Fe2S3O 12 ·9H2O is 1 mol: 1.25 mol; the amount of the solvent is 50 mL, and the solvent is a mixture of CHCl3 and DMF with a volume ratio of 4:1; the distillation temperature is 70 °C; the filtration is carried out under normal pressure; the washing treatment is to wash 3 times each with methanol and deionized water; the parameters of the reflux conditions are: the reflux temperature is 130 °C and the reflux time is 3 h;

[0072] Step 2: React the Fe 3+ -TCPP solid, SOCl2 and a solvent under reflux conditions. After the reaction is completed and the temperature is lowered to room temperature, the obtained reaction product is successively subjected to filtration and washing treatments to obtain Fe 3+ -TCPP-COCl solid; wherein, the molar ratio of the Fe 3+ -TCPP solid to SOCl2 is 1:5; the solvent is CH2ClCH2Cl; the volume ratio of SOCl2 to CH2ClCH2Cl is 1:6; the parameters of the reflux conditions are: the reflux temperature is 83 °C and the reflux time is 2 h; the filtration is carried out under normal pressure; the washing treatment is to wash 3 times each with methanol and deionized water;

[0073] Step 3: Grind Fe 3+ -TCPP-COCl solid and p-phenylenediamine (PD) at room temperature for reaction. After the reaction is completed, wash and dry the obtained reaction product in sequence to obtain a porphyrin COF material (Fe 3+ -Por-COF); wherein, the molar ratio of Fe 3+ -TCPP-COCl solid to p-phenylenediamine is 1:2; the grinding is carried out at room temperature for 20 min; the washing is carried out 3 times each with ethanol and deionized water; the drying treatment temperature is 105 °C and the time is 6 h.

[0074] Example 2

[0075] A preparation method of a porphyrin COF material, comprising the following steps:

[0076] Step 1: React 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin, Fe2S3O 12 ·9H2O and a solvent under reflux conditions. After the reaction is completed and the temperature is lowered to room temperature, distill, filter and wash the obtained reaction product in sequence to obtain Fe 3+ -TCPP solid; wherein, the molar ratio of 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin to Fe2S3O 12 ·9H2O is 1 mol:1.4 mol; the dosage of the solvent is 50 mL, and the solvent is a mixture of CHCl3 and DMF with a volume ratio of 5:1; the distillation temperature is 70 °C; the filtration is carried out under normal pressure; the washing treatment is carried out 4 times each with methanol and deionized water; the parameters of the reflux conditions are: the reflux temperature is 135 °C and the reflux time is 4 h;

[0077] Step 2: React Fe 3+ -TCPP solid, SOCl2 and a solvent under reflux conditions. After the reaction is completed and the temperature is lowered to room temperature, filter and wash the obtained reaction product in sequence to obtain Fe 3+ -TCPP-COCl solid; wherein, the molar ratio of Fe 3+ -TCPP solid to SOCl2 is 1:6; the solvent is CH2ClCH2Cl; the volume ratio of SOCl2 to CH2ClCH2Cl is 1:7; the parameters of the reflux conditions are: the reflux temperature is 84 °C and the reflux time is 3 h; the filtration is carried out under normal pressure; the washing treatment is carried out 4 times each with methanol and deionized water;

[0078] Step 3: Take Fe 3+-TCPP-COCl solid and p-phenylenediamine (PD) are ground at room temperature for reaction. After the reaction is completed, the obtained reaction product is washed and dried successively to obtain a porphyrin COF material (Fe 3+ -Por-COF); wherein, the molar ratio of Fe 3+ -TCPP-COCl solid to p-phenylenediamine is 1:2.3; the grinding is carried out at room temperature for 30 min; the washing is carried out 4 times each with ethanol and deionized water; the drying treatment temperature is 110 °C and the time is 7 h.

[0079] Example 3

[0080] A preparation method of a porphyrin COF material, comprising the following steps:

[0081] Step 1: 5,10,15,20-Tetrakis(4-carboxyphenyl)porphyrin, Fe2S3O 12 ·9H2O and a solvent are reacted under reflux conditions. After the reaction is completed and the temperature is lowered to room temperature, the obtained reaction product is distilled, filtered and washed successively to obtain Fe 3+ -TCPP solid; wherein, the molar ratio of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin to Fe2S3O 12 ·9H2O is 1 mol:1.5 mol; the amount of the solvent is 50 mL, and the solvent is a mixture of CHCl3 and DMF with a volume ratio of 6:1; the distillation temperature is 70 °C; the filtration is carried out under normal pressure; the washing treatment is carried out 5 times each with methanol and deionized water; the parameters of the reflux conditions are: the reflux temperature is 140 °C and the reflux time is 5 h;

[0082] Step 2: Fe 3+ -TCPP solid, SOCl2 and a solvent are reacted under reflux conditions. After the reaction is completed and the temperature is lowered to room temperature, the obtained reaction product is filtered and washed successively to obtain Fe 3+ -TCPP-COCl solid; wherein, the molar ratio of Fe 3+ -TCPP solid to SOCl2 is 1:8; the solvent is CH2ClCH2Cl; the volume ratio of SOCl2 to CH2ClCH2Cl is 1:8; the parameters of the reflux conditions are: the reflux temperature is 85 °C and the reflux time is 4 h; the filtration is carried out under normal pressure; the washing treatment is carried out 5 times each with methanol and deionized water;

[0083] Step 3: Fe 3+ -TCPP-COCl solid and p-phenylenediamine (PD) are ground at room temperature for reaction. After the reaction is completed, the obtained reaction product is washed and dried successively to obtain a porphyrin COF material (Fe 3+-Por-COF); wherein, Fe 3+ The molar ratio of -TCPP-COCl solid to p-phenylenediamine is 1:2.5; the grinding is carried out at room temperature for 40 min; the washing is carried out 5 times each with ethanol and deionized water; the drying treatment temperature is 115 °C and the time is 8 h.

[0084] Example 4

[0085] A preparation method of a porphyrin COF material, comprising the following steps:

[0086] Step 1: React 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin, Fe2S3O 12 ·9H2O and a solvent under reflux conditions. After the reaction ends and the temperature drops to room temperature, the obtained reaction product is successively subjected to distillation, filtration and washing treatments to obtain Fe 3+ -TCPP solid; wherein, the molar ratio of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin to FeCl3·6H2O is 1 mol:1.5 mol; the amount of the solvent is 50 mL, and the solvent is a mixture of CHCl3 and DMF with a volume ratio of 6:1; the distillation temperature is 70 °C; the filtration is carried out under normal pressure; the washing treatment is carried out 5 times each with methanol and deionized water; the parameters of the reflux conditions are: the reflux temperature is 140 °C and the reflux time is 5 h.

[0087] Step 2: React Fe 3+ -TCPP solid, SOCl2 and a solvent under reflux conditions. After the reaction ends and the temperature drops to room temperature, the obtained reaction product is successively subjected to filtration and washing treatments to obtain Fe 3+ -TCPP-COCl solid; wherein, 3+ the molar ratio of Fe

[0088] Step 3: Grind and react Fe 3+ -TCPP-COCl solid and p-phenylenediamine (PD) at room temperature. After the reaction ends, the obtained reaction product is successively subjected to washing and drying treatments to obtain a porphyrin COF material (Fe 3+ -Por-COF); wherein, Fe 3+-The molar ratio of -TCPP-COCl solid to p-phenylenediamine is 1:2.5; the grinding is carried out at room temperature for 40 min; the washing is carried out 5 times each with ethanol and deionized water; the drying treatment temperature is 115 °C and the time is 8 h.

[0089] Example 5

[0090] A preparation method of a porphyrin COF material, comprising the following steps:

[0091] Step 1: React 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin, Fe2S3O 12 ·9H2O and a solvent under reflux conditions. After the reaction is completed and the temperature drops to room temperature, the obtained reaction product is successively subjected to distillation, filtration and washing treatments to obtain Fe 3+ -TCPP solid; wherein, the molar ratio of 5, 10, 15, 20-tetrakis(4-carboxyphenyl)porphyrin to Fe2S3O 12 ·9H2O is 1 mol:1.5 mol; the dosage of the solvent is 50 mL, and the solvent is a mixture of CHCl3 and DMF with a volume ratio of 6:1; the distillation temperature is 70 °C; the filtration is carried out under normal pressure; the washing treatment is carried out 5 times each with methanol and deionized water; the parameters of the reflux conditions are: the reflux temperature is 140 °C and the reflux time is 5 h.

[0092] Step 2: React Fe 3+ -TCPP solid, PCl5 and a solvent under reflux conditions. After the reaction is completed and the temperature drops to room temperature, the obtained reaction product is successively subjected to filtration and washing treatments to obtain Fe 3+ -TCPP-COCl solid; wherein, the molar ratio of Fe 3+ -TCPP solid to PCl5 is 1:8; the solvent is CH2ClCH2Cl; the volume ratio of PCl5 to CH2ClCH2Cl is 1:8; the parameters of the reflux conditions are: the reflux temperature is 85 °C and the reflux time is 4 h; the filtration is carried out under normal pressure; the washing treatment is carried out 5 times each with methanol and deionized water;

[0093] Step 3: Grind and react Fe 3+ -TCPP-COCl solid and p-phenylenediamine (PD) at room temperature. After the reaction is completed, the obtained reaction product is successively subjected to washing and drying treatments to obtain a porphyrin COF material (Fe 3+ -Por-COF); wherein, the molar ratio of Fe 3+ -TCPP-COCl solid to p-phenylenediamine is 1:2.5; the grinding is carried out at room temperature for 40 min; the washing is carried out 5 times each with ethanol and deionized water; the drying treatment temperature is 115 °C and the time is 8 h.

[0094] Example 6

[0095] A preparation method of a porphyrin COF material, comprising the following steps:

[0096] Step 1: React 5,10,15,20 - tetra(4 - carboxyphenyl)porphyrin, Fe₂S₃O 12 ·9H₂O and a solvent under reflux conditions. After the reaction ends and the temperature drops to room temperature, the obtained reaction product is successively subjected to distillation, filtration and washing treatments to obtain Fe 3+ -TCPP solid; wherein, the molar ratio of 5,10,15,20 - tetra(4 - carboxyphenyl)porphyrin to Fe₂S₃O 12 ·9H₂O is 1mol:1.5mol; the amount of the solvent is 50 mL, and the solvent is a mixture of CHCl₃ and DMF with a volume ratio of 6:1; the distillation temperature is 70 °C; the filtration is carried out under normal pressure; the washing treatment is to wash 5 times each with methanol and deionized water; the parameters of the reflux conditions are: the reflux temperature is 140 °C and the reflux time is 5 h.

[0097] Step 2: React the Fe 3+ -TCPP solid, PCl₃ and a solvent under reflux conditions. After the reaction ends and the temperature drops to room temperature, the obtained reaction product is successively subjected to filtration and washing treatments to obtain Fe 3+ -TCPP - COCl solid; wherein, the molar ratio of the Fe 3+ -TCPP solid to PCl₃ is 1:8; the solvent is CH₂ClCH₂Cl; the volume ratio of PCl₃ to CH₂ClCH₂Cl is 1:8; the parameters of the reflux conditions are: the reflux temperature is 85 °C and the reflux time is 4 h; the filtration is carried out under normal pressure; the washing treatment is to wash 5 times each with methanol and deionized water;

[0098] Step 3: Grind and react the Fe 3+ -TCPP - COCl solid and p - phenylenediamine (PD) at room temperature. After the reaction ends, the obtained reaction product is successively subjected to washing and drying treatments to obtain the porphyrin COF material (Fe 3+ -Por - COF); wherein, the molar ratio of the Fe 3+ -TCPP - COCl solid to p - phenylenediamine is 1:2.5; the grinding is carried out at room temperature for 40 min; the washing is to wash 5 times each with ethanol and deionized water; the drying treatment temperature is 115 °C and the time is 8 h.

[0099] The porphyrin COF materials prepared in different embodiments of the present invention were tested for pollutant degradation performance in accordance with the national standards in the field of photocatalysis. The specific national standards are as follows: GB / T 23762−2009 (Test method for purification of photocatalytic materials in aqueous solution system). The test results are shown in Table 1. As can be seen from Table 1, the porphyrin COF materials prepared in the present invention have good degradation effects on both organic dyes and antibiotics; especially, the porphyrin COF materials have better effects when the three synergistic effects of adsorption, photocatalysis, and PDS activation are combined. For rhodamine, it can be completely degraded within 30 minutes under the synergistic action of the three, while at least 90 minutes are required for individual action; for tetracycline, the synergistic action of the three has little effect on the degradation time, but greatly improves the degradation efficiency; moreover, the degradation effect of the porphyrin COF materials changes little after 5 cycles, indicating its high stability.

[0100] Table 1 Pollutant degradation performance data of porphyrin COF materials prepared in different embodiments

[0101]

[0102] Note: All experiments were carried out under the conditions of a room temperature of 20 °C, a pH value of 7, and a xenon lamp power of 500 W.

[0103] Figure 1 This is the SEM image of the porphyrin COF material prepared in Example 3 of the present invention. As can be seen from the figure, the porphyrin COF material prepared in the present invention has a layered structure.

[0104] Figure 2 This is the elemental point scan image of the porphyrin COF material prepared in Example 3 of the present invention. It can be seen that the C, O, N, and Fe elements are evenly distributed in the porphyrin COF material, which also proves the successful coordination of ferric ions.

[0105] Figure 3 This is the infrared spectrum of the porphyrin COF material prepared in Example 3 of the present invention. From the infrared absorption peaks at 1514 cm -1 and 1643~1641 cm -1 corresponding to the stretching vibration bands of the amide bond N-H and C=O, it can be shown that the porphyrin COF material connected by amide bonds has been successfully formed.

[0106] Figure 4 This is the PXRD pattern of the porphyrin COF material prepared in Example 3 of the present invention. It can be seen that two main diffraction peaks appear at 2.1° and 7.8°, and a diffuse bread-like peak appears at 22.4°, which belongs to the π-π stacking diffraction peak of the obtained layered porphyrin COF material, indicating that Fe 3+ -Por-COF has a certain degree of crystallinity.

[0107] Figure 5 The XPS spectrum of the porphyrin COF material prepared in Example 3 of the present invention is shown. It can be seen that the C 1s fine spectrum is located at 284.8, 285.30 and 288.20 eV, the N 1s fine spectrum is located at 398.24, 399.91 and 402.46 eV, the O 1s fine spectrum is located at 531.04 and 532.83 eV, and the Fe 2p fine spectrum is located at 711.29 eV, with a satellite peak around it, further proving the successful synthesis of iron(III) porphyrin.

[0108] Figure 6 The thermal stability diagram of the porphyrin COF material prepared in Example 3 of the present invention is shown. It can be seen that in the first stage, from 30 to 90 °C, the initial weight reduction of the porphyrin COF material corresponds to the evaporation of adsorbed water and residual solvent molecules; in the second stage, from 90 to 530 °C, the gradual weight loss of the porphyrin COF material is due to the decomposition of functional groups on the upper edge; in the third stage, from 530 to 800 °C, the severe weight loss of the porphyrin COF material marks the beginning of the structural collapse and decomposition of the porphyrin COF material; at 800 °C, the porphyrin COF material still shows a mass retention rate of 59.45%, indicating that Fe 3+ -Por-COF has good thermal stability.

[0109] Figure 7 The nitrogen adsorption-desorption experimental data diagram of the porphyrin COF material prepared in Example 3 of the present invention is shown. The results show that the porphyrin COF material has a type III adsorption mode, which is characteristic of materials with mesoporous structures; from data processing, the surface area of the porphyrin COF material is 48.76 m 2 / g, the total pore volume is 0.231 cm 3 / g, and the average pore diameter is 25.82 nm. Therefore, Fe 3+ -Por-COF has potential adsorption performance.

[0110] Figure 8 The UV-visible diffuse reflectance spectrum of the porphyrin COF material prepared in Example 3 of the present invention is shown. Thanks to the highly conjugated structure of porphyrin in the porphyrin COF material, Fe 3+ -Por-COF exhibits full-spectrum response (300 - 700 nm), almost covering the entire visible light region; the band gap of Fe 3+ -Por-COF calculated by the Kubelka–Munk equation is 2.5 eV.

[0111] The above content is only to illustrate the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A preparation method of a porphyrin COF material, characterized in that, It includes the following steps: S1: React tetracarboxyl porphyrin, ferric salt and a solvent under reflux conditions. After the reaction is completed, post-treat the obtained reaction product to obtain Fe 3+ -TCPP solid; S2: Add Fe 3+ -TCPP solid, acyl chlorination reagent and solvent to react under reflux conditions. After the reaction is completed, post-treat the obtained reaction product to obtain Fe 3+ -TCPP-COCl solid; S3: Add Fe 3+ -TCPP-COCl solid and p-phenylenediamine and grind them for reaction. After the reaction is completed, post-treat the obtained reaction product to obtain the porphyrin COF material; In S1, the dosage ratio of the tetracarboxyl porphyrin, ferric salt and solvent is 1 mol:(1.25 - 1.5) mol:50 mL; the solvent is a mixture of CHCl3 and DMF with a volume ratio of (4 - 6):1; the parameters of the reflux condition are: the reflux temperature is 130 - 140 °C, and the reflux time is 3 - 5 h. The tetracarboxyl porphyrin is 5, 10, 15, 20 - tetrakis(4 - carboxyphenyl)porphyrin. The ferric salt is Fe2(SO4)3·9H2O. In S2, the molar ratio of the Fe 3+ -TCPP solid to the acylating agent is 1:(5-8); The solvent is CH2ClCH2Cl; the volume ratio of the acyl chlorination reagent and the solvent is 1:(6 - 8). The acyl chlorination reagent is one of SOCl2, PCl5 and PCl3. The parameters of the reflux condition are: the reflux temperature is 83 - 85 °C, and the reflux time is 2 - 4 h. In S3, the molar ratio of the Fe 3+ -TCPP-COCl solid to p-phenylenediamine is 1:(2 - 2.5); the grinding is carried out at room temperature for 20 - 40 min.

2. The preparation method of a porphyrin COF material according to claim 1, wherein, In S1, the post - treatment includes distillation, filtration and washing treatments carried out in sequence; the temperature of the distillation is 70 - 72 °C; the filtration is carried out under normal pressure; the washing treatment is to wash 3 - 5 times with methanol and deionized water respectively.

3. The preparation method of a porphyrin COF material according to claim 1, characterized in that, In S2, the post - treatment includes filtration and washing treatments carried out in sequence; the filtration is carried out under normal pressure; the washing treatment is to wash 3 - 5 times with methanol and deionized water respectively.

4. The preparation method of a porphyrin COF material according to claim 1, characterized in that In S3, the post - treatment includes washing and drying treatments carried out in sequence; the washing is to wash 3 - 5 times with ethanol and deionized water respectively; the temperature of the drying treatment is 105 - 115 °C, and the time is 6 - 8 h.

5. A porphyrin COF material, characterized in that, It is prepared by using the preparation method described in any one of claims 1 - 4.

6. Use of the porphyrin COF material according to claim 5 in degrading organic pollutants in water.

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