Layered pillar-type covalent organic framework material and preparation method thereof

Abstract

The application relates to a kind of layer column type covalent organic framework materials and a preparation method thereof, and belongs to the field of polymer materials.The application provides a kind of layer column type covalent organic framework material, which is prepared from 5,10,15,20-tetra (4-aminobenzene) porphyrin-M or 5,10,15,20-tetra (4-formaldehyde phenyl) porphyrin-M, aromatic dialdehyde / amine as raw material, combined with column supporting molecule, under the action of Lewis acid catalyst (metal salt of trifluoromethanesulfonic acid).The application introduces column supporting molecule into framework interlayer, constructs three-dimensional layer column type structure, so that the material has excellent electrochemical activity and high selective CO2 reduction performance, and shows ideal application prospect in electrocatalytic CO2-CO conversion.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of preparation of covalent organic framework (COFs) materials, and particularly relates to a layer-pillared covalent organic framework material taking pyrazine (Pz), bipyridine (Bp) and terephthalic acid (TPA) as pillar molecules and a preparation method thereof. BACKGROUND

[0002] COFs are a kind of crystalline porous materials assembled by dynamic covalent bonds of organic ligands, and have been widely concerned in the fields of catalysis, gas storage, separation and sensors due to their structural tunability, high specific surface area and rich active sites.

[0003] With the overuse of fossil fuels and the massive emission of greenhouse gas CO2, the world is facing severe environmental and energy challenges. COFs have become an ideal material for electrocatalytic reduction of carbon dioxide due to their unique high specific surface area, high porosity and structural tunability. However, two-dimensional (2D) COFs still face difficulties in practical applications, specifically, due to the strong π-π interaction between layers, which usually leads to narrow interlayer spacing (usually less than 0.5 nm), resulting in serious stacking effect. This stacking effect not only shields the active sites, reduces the effective surface area, but also significantly affects the selectivity and current density of the catalyst.

[0004] To solve the above problems, two ways can be adopted, one is to prepare single-layer or multi-layer structure COFs to fully expose the catalytic center and enhance the catalytic activity; the other is to insert “pillar molecules” into the interlayer of COFs by introducing “pillar molecules” to insert into the interlayer of COFs, thereby expanding the interlayer spacing and reducing the stacking effect, so as to optimize the material performance. SUMMARY

[0005] The application proposes a preparation method of layer-pillared covalent organic framework material, which improves the crystallinity and interlayer spacing of COFs, and avoids substantial modification of the original structure. The material prepared by the method can be widely used in the field of electrocatalytic reduction of carbon dioxide.

[0006] A layer-pillared covalent organic framework material, the structural formula is as follows:

[0007]

[0008] Wherein, X or Y is C or N, X and Y are not the same;

[0009] M is a transition metal;

[0010] is

[0011] Ar or Ar' is one of the following:

[0012]

[0013] R is alkyl or alkoxy;

[0014] The M-Por is TAPP or TFPP.

[0015] The transition metal is Co, Fe or Cu.

[0016] The alkyl or alkoxy is H, CH з , C2H5, OH or OMe.

[0017] A preparation method of a layer column type covalent organic framework material, characterized in that the method comprises the following steps:

[0018] Step 1, M-Por, aromatic dialdehyde or aromatic diamine, and pillar molecule are mixed in a molar ratio of 1:2:1~2, so that the concentration of M-Por is 0.05M, then a mixture of n-butanol and o-dichlorobenzene is added, and the mixture is uniformly dispersed by ultrasonic, and then a catalyst is added;

[0019] Step 2, the mixed system of step 1 is sequentially treated by liquid nitrogen freezing, vacuumizing and degassing, and then the system is sealed to obtain a crude product;

[0020] Step 3, the crude product is obtained by vacuum filtration, washing, Soxhlet extraction and vacuum drying.

[0021] The catalyst is a Lewis acid, i.e. a metal triflate, including scandium triflate, zinc triflate, iron triflate, yttrium triflate and indium triflate, and the concentration is 0.09~0.3mol / L.

[0022] The volume ratio of the n-butanol and o-dichlorobenzene mixture is 1:1.

[0023] The crude product is washed by water and acetone by vacuum filtration, and then extracted by 1,4-dioxane and acetone by Soxhlet extraction for 24 hours, and then vacuum dried at 65℃ for 12 hours to obtain the layer column type covalent organic framework material.

[0024] The present application provides a new method, by introducing pillar molecules containing pyridine nitrogen elements or carboxyl groups, such as pyrazine Pz, bipyridine Bp, terephthalic acid TPA, into two-dimensional COFs, to construct three-dimensional layer column type COFs materials. This method significantly improves the crystallinity and interlayer spacing of COFs, while avoiding substantial modification of the original structure. By adjusting the length of the "pillar molecule", the interlayer spacing can be accurately controlled, thereby further optimizing the material performance, and providing a new technical path for its application in the electrocatalytic reduction of carbon dioxide.

[0025] The framework material of the present application has the following significant advantages:

[0026] 1. Crystallinity and interlayer spacing optimization: effectively improve the crystallinity and interlayer spacing of COFs, while avoiding significant changes to the monomer structure.

[0027] 2. Adjustable interlayer spacing: by adjusting the length of the "pillar molecule", the interlayer spacing can be precisely controlled, thereby optimizing the framework performance.

[0028] 3. Enhancement of active sites: significantly improve the exposure of active sites, improve the diffusion channels of guest molecules, ions and electrons.

[0029] 4. Electronic and pore regulation: realize the modulation of the electronic properties of COFs and catalytic centers, and fine-tune the porosity to increase the specific surface area and improve the structural stability.

[0030] 5. Excellent catalytic performance: the material shows excellent performance in terms of electrochemical activity and CO2 to CO conversion selectivity, and shows broad application prospects in the field of carbon dioxide electrocatalytic reduction. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 Preparation flow chart of the present application's layer-pillar type covalent organic framework.

[0032] Figure 2 The powder X-ray diffraction pattern of the two-dimensional covalent organic framework-COF-366-Co; 3.50, 4.15, 7.2 degrees are the characteristic peaks of the material, and the strongest peak is at 3.50 degrees with a diffraction intensity of about 1130.

[0033] Figure 3 The powder X-ray diffraction pattern of the layer-pillar type covalent organic framework-COF-366-Co-Pz prepared by the present application;

[0034] Figure (a) is Pz is 1.2 eq, figure (b) is Pz is 2.0 eq; 3.44, 4.17, 6.88 and 8.38 degrees are the characteristic peaks of the material, and the strongest peak is at 3.44 degrees with a diffraction intensity of about 1300, slightly higher than COF-366-Co (1130); but when the equivalent of Pz increases, the crystallinity decreases; when the equivalent of Pz is 2 eq, the strongest peak diffraction intensity is about 1090, close to the strongest peak diffraction intensity (1130) of COF-366-Co.

[0035] Figure 4 (a) is the powder X-ray diffraction pattern of the covalent organic framework-Bpy CoTPP-DMTP-COF with similar structure prepared by the preparation method reported in the literature, Figure 4(b) the powder X-ray diffraction pattern of covalent organic framework-CoTPP-DMTP-COF without introducing Bpy (Bpy = Bp) ;

[0036] It can be seen from the figure that the crystallinity of the covalent organic framework-BpyCoTPP-DMTP-COF prepared by introducing Bpy using the method reported in the literature is obviously decreased compared with the covalent organic framework-CoTPP-DMTP-COF without introducing Bpy; the literature is Xie SL, Liu RY, Liu NY, et al. Vertically Expanded Covalent Organic Frameworks for Photocatalytic Water Oxidation into Oxygen. Angew Chem Int Edit. Nov 19 2024.

[0037] Figure 5 the powder X-ray diffraction pattern of the layer-pillared covalent organic framework-COF-366-Co-Bp prepared in the application;

[0038] Fig. (a) Bp is 1.2 eq, Fig. (b) Bp is 3.0 eq; 3.48, 4.01, 6.96 and 10.09 degrees are material characteristic peaks, the strongest peak is at 3.48 degrees, and the diffraction intensity is about 3004, which is much higher than that of COF-366-Co (1130); but when the equivalent of Bp increases, the crystallinity also decreases; when the equivalent of Bp is 3 eq, the diffraction intensity of the strongest peak is about 956, which is lower than the diffraction intensity of the strongest peak of COF-366-Co (1130).

[0039] Figure 6 the nitrogen adsorption-desorption curve (a) and the pore size distribution diagram (b) of the two-dimensional covalent organic framework-COF-366-Co;

[0040] The adsorption-desorption curve is type I isotherm, indicating that the structure is microporous structure, and the specific surface area of the material is calculated to be 1055 m 2 g -1 ; according to the pore size distribution diagram, the pore size is mainly distributed at 1.95 nm, and the cumulative pore volume is 0.374 cm 3 / g.

[0041] Figure 7 the nitrogen adsorption-desorption curve (a) and the pore size distribution diagram (b) of the layer-pillared covalent organic framework-COF-366-Co-Pz (1.2 eq) prepared in the application;

[0042] The adsorption-desorption curve of COF-366-Co-Pz (1.2 eq) is a type I isotherm curve, indicating that the structure is microporous, and the specific surface area of the material is calculated to be 1970 m 2 g -1 , which is much higher than the specific surface area (1055 m 2 g -1 ) of COF-366-Co; according to the pore size distribution diagram, the pore size is mainly distributed at 1.24 nm and 1.78 nm, and the cumulative pore volume is 0.741 cm 3 / g; which is also much higher than the cumulative pore volume (0.374 cm 3 / g) of COF-366-Co.

[0043] Figure 8 The nitrogen adsorption-desorption curve (a) and the pore size distribution diagram (b) of the covalent organic framework-Bpy CoTPP-DMTP-COF with a similar structure prepared by the preparation method reported in the literature and the nitrogen adsorption-desorption curve (c) and the pore size distribution diagram (d) of the covalent organic framework-CoTPP-DMTP-COF without introducing Bpy are shown in the figure;

[0044] It can be seen from the figure that after introducing Bpy according to the preparation method reported in the literature, the specific surface area and the cumulative pore volume of the covalent organic framework-Bpy CoTPP-DMTP-COF are lower than those of the covalent organic framework-CoTPP-DMTP-COF without introducing Bpy; and the specific surface area and the cumulative pore volume of CoTPP-DMTP-COF are lower than those of COF-366-Co; see the literature: Xie SL, Liu RY, Liu NY, et al. Vertically Expanded Covalent Organic Frameworks for Photocatalytic Water Oxidation into Oxygen. Angew Chem Int Edit. Nov 19 2024.

[0045] Figure 9 The nitrogen adsorption-desorption curve (a) and the pore size distribution diagram (b) of the layer columnar covalent organic framework-COF-366-Co-Bp (1.2 eq) prepared by the present application are shown in the figure;

[0046] According to the adsorption curve, the adsorption-desorption curve of COF-366-Co-Bp (1.2 eq) is a type I isotherm curve, indicating that the structure is microporous, and the specific surface area of the material is calculated to be 1588 m 2 g -1 , which is higher than the specific surface area (1055 m 2 g-1 );according to the pore size distribution, the pore size mainly distributes at 1.95 nm, and the cumulative pore volume is 0.598 cm 3 / g; which is also higher than the cumulative pore volume (0.374 cm 3 / g) of COF-366-Co; naturally, the specific surface area and the cumulative pore volume of COF-366-Co-Bp (1.2 eq) are far higher than those of the similar covalent organic framework-BpyCoTPP-DMTP-COF prepared by the reported preparation method.

[0047] Figure 10 It is a transmission electron microscope photo of the two-dimensional covalent organic framework-COF-366-Co.

[0048] The figure shows obvious lattice fringes, and the interplanar spacing is about 0.62 nm.

[0049] Figure 11 It is a transmission electron microscope photo of the layer-pillar type covalent organic framework-COF-366-Co-Pz (1.2 eq) prepared in the application.

[0050] The figure shows obvious lattice fringes, and the interplanar spacing is about 1.43 nm, which is far greater than the interplanar spacing (0.62 nm) of COF-366-Co.

[0051] Figure 12 It is a transmission electron microscope photo of the layer-pillar type covalent organic framework-COF-366-Co-Bp (1.2 eq) prepared in the application.

[0052] The figure shows obvious lattice fringes, and the interplanar spacing is about 1.75 nm, which is far greater than the interplanar spacing (0.62 nm) of COF-366-Co.

[0053] Figure 13 It is a linear sweep voltammetry curve (a) and a curve (b) of the Faraday efficiency (FE -1 %) of electrocatalytic generation of CO at-0.5V to-1.0V of the two-dimensional covalent organic framework-COF-366-Co in CO2 saturation, 0.1M KHCO3 electrolyte, and the scanning rate is 5mV·s CO

[0054] According to the voltammetry curve, when the potential is-1.20V, the current density is 24mA / cm 2 ; according to the curve of the Faraday efficiency (FE CO %), when the potential reaches-0.63V, the FE CO % reaches the highest point of 89.6%; when the potential continues to rise, the FE CO % starts to rapidly decrease.​

[0055] Figure 14 The columnar covalent organic framework -COF-366-Co-Pz (1.2 eq) prepared for this invention was subjected to a scan rate of 5 mV·s in CO2-saturated 0.1 M KHCO3 electrolyte. -1 Linear sweep voltammetry curve (a) and the Faradaic efficiency (FE) of electrocatalytic CO production at potentials from -0.5V to -1.0V. CO %) curve (b);

[0056] The current density is 27 mA / cm² when the potential is -1.20V, as shown in the current-voltage curve. 2 According to Faraday efficiency (FE) CO The FE curve shows that when the potential reaches -0.63V, its FE CO The percentage reached a peak of 90.3%, an improvement over COF-366-Co; and when the potential was between -0.63V and -0.74V, its FE CO The percentage remains above 90%.

[0057] Figure 15 The columnar covalent organic framework -COF-366-Co-Bp (1.2 eq) prepared for this invention was subjected to a scan rate of 5 mV·s in CO2-saturated 0.1 M KHCO3 electrolyte. -1 Linear sweep voltammetry curve (a) and the Faradaic efficiency (FE) of electrocatalytic CO production at potentials from -0.5V to -1.0V. CO %) curve (b);

[0058] The current density is 37 mA / cm² when the potential is -1.20V, as shown in the current-voltage curve. 2 According to Faraday efficiency (FE) CO The FE curve shows that when the potential reaches -0.63V, its FE CO The percentage reached a peak of 91.3%, an improvement over COF-366-Co; and when the potential was between -0.63V and -0.81V, its FE CO The percentage remains above 90%. Detailed Implementation

[0059] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention.

[0060] Embodiment 1: A preparation method of a layer-pillar type covalent organic framework material, the specific steps are as follows:

[0061] S1: 5,10,15,20-tetrakis(4-aminophenyl)porphyrin-cobalt (TAPP-Co, 18 mg, 0.025 mmol), p-xylylene (10 mg, 0.075 mmol) and Pz (2.4 mg, 0.03 mmol, 1.2 eq) were placed in an ampoule with a volume of 10 mL, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of scandium triflate catalyst (9.1 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0062] S2: The above-mentioned mixed system was sequentially subjected to vacuum degassing treatment for 3 times under liquid nitrogen freezing, and the ampoule was sealed by flame gun baking for sealing under vacuum, and was placed in a 120°C oven for 2 days of standing reaction to obtain a crude product;

[0063] S3: The crude product was washed by water and acetone, and then was subjected to Soxhlet extraction with 1,4-dioxane and acetone for 24 hours respectively, and then was dried at 65°C under vacuum for 12 hours to obtain a purple red solid powder 17 mg with a yield of 56.7%, which was recorded as COF-366-Co-Pz (1.2 eq).

[0064] The powder X-ray diffraction pattern of the layer-pillar type covalent organic framework-COF-366-Co-Pz (1.2 eq) prepared in this embodiment is shown in Figure 3 (a), which indicates that COF-366-Co-Pz (1.2 eq) has a high crystallinity. Among them, 3.44, 4.17, 6.88 and 8.38 degrees are the characteristic peaks of the material, and the strongest peak is located at 3.44 degrees with a diffraction intensity of about 3004, which is much higher than that of COF-366-Co (1130, as shown in Figure 2 ). Figure 7 The nitrogen adsorption-desorption curve (a) and the pore size distribution diagram (b) of COF-366-Co-Pz (1.2 eq) prepared in this embodiment are shown in Figure 7 (a) and (b), respectively. As can be seen from (a), the adsorption-desorption curve of COF-366-Co-Pz (1.2 eq) is a type I isotherm curve, indicating that the structure of the material is microporous structure, and the specific surface area of the material is calculated to be 1970 m 2 g -1 , which is much higher than the specific surface area of COF-366-Co (1055 m 2 g -1 , as shown in Figure 6 (a)); according to the pore size distribution diagram 7(b), the pore size is mainly distributed at 1.24 nm and 1.78 nm, and the cumulative pore volume is 0.741 cm 3 / g; also significantly higher than the cumulative pore volume of COF-366-Co (0.391 cm³). 3 / g, such as Figure 6 (b)). For example Figure 11 The transmission electron microscope (TEM) image of COF-366-Co-Pz (1.2 eq) prepared for the example shows obvious lattice fringes with a spacing of approximately 1.43 nm, which is much larger than the interplanar spacing of COF-366-Co (0.62 nm). Figure 10 ).like Figure 14 COF-366-Co-Pz (1.2 eq) was detected in CO2-saturated 0.1 M KHCO3 electrolyte at a scan rate of 5 mV·s. -1 Linear sweep voltammetry curves and the Faraday efficiency (FE) for electrocatalytic CO production at potentials ranging from -0.5V to -1.0V are shown. CO %) curve; From the 14(a) volt-ampere curve, it can be seen that when the potential is -1.20V, the current density is 27mA / cm. 2 Higher than COF-366-Co (24mA / cm) 2 ,like Figure 13 (a)); According to 14(b) Faraday efficiency (FE) CO The FE curve shows that when the potential reaches -0.63V, its FE CO The percentage reached a peak of 90.3%, relative to COF-366-Co(FE) CO (89.6%) improved; and when the potential is between -0.63V and -0.74V, its FE CO The percentage remained above 90%, while COF-366-Co decreased rapidly with increasing potential.

[0065] Example 2: A method for preparing a layered columnar covalent organic framework material, the specific steps of which are as follows:

[0066] S1: Place TAPP-Co (18 mg, 0.025 mmol), terephthalaldehyde (10 mg, 0.075 mmol), and Bp (4.68 mg, 0.03 mmol, 1.2 eq) in a 10 mL ampoule, add 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene, and sonicate to disperse the raw materials evenly; then add the pre-prepared scandium trifluoromethanesulfonate catalyst aqueous solution (9.1 mg dissolved in 65 μL of water, 0.284 mol / L);

[0067] S2: The above mixture was subjected to liquid nitrogen freezing and vacuum degassing treatment three times in sequence. Under vacuum, the ampoule was sealed by heating with a flame gun and placed in a 120°C oven for two days to obtain the crude product.

[0068] S3: The crude product was washed with water and acetone by filtration, then extracted with 1,4-dioxane and acetone for 24 hours, respectively. After vacuum drying at 65°C for 12 hours, a purple red solid powder of 18 mg was obtained, with a yield of 55%, which was recorded as COF-366-Co-Bp (1.2 eq).

[0069] The powder X-ray diffraction pattern of the layer columnar covalent organic framework-COF-366-Co-Bp (1.2 eq) prepared in this example is shown in Figure 5 (a), which indicates that COF-366-Co-Bp (1.2 eq) has a high crystallinity. The characteristic peaks of the material are at 3.48, 4.01, 6.96 and 10.09 degrees; the strongest peak is at 3.48 degrees, with a diffraction intensity of about 1296, which is slightly higher than that of COF-366-Co (1130, as shown in Figure 2 ), indicating that the crystallinity of the material has slightly increased after the introduction of Bp. It can be seen from Figure 4 that the crystallinity of the covalent organic framework-Bpy CoTPP-DMTP-COF prepared by introducing Bpy using the method reported in the literature has obviously decreased compared with the covalent organic framework-CoTPP-DMTP-COF without the introduction of Bpy; this also indicates that the preparation method of the present application is superior to the preparation method reported in the literature. As shown in Figure 9 The nitrogen adsorption-desorption curve (a) and the pore size distribution (b) of COF-366-Co-Bp (1.2 eq) prepared in this example are shown in Figure 9 (a) and (b), respectively. It can be seen from Figure 6 (a) that the adsorption-desorption curve of COF-366-Co-Bp (1.2 eq) is a type I isotherm, indicating that the structure of the material is microporous. The specific surface area of the material is calculated to be 1599 m 2 g -1 , which is higher than the specific surface area of COF-366-Co (1055 m 2 g -1 , as shown in Figure 6 (a)); according to the pore size distribution in 9(b), the pore size is mainly distributed at 1.95 nm, and the cumulative pore volume is 0.598 cm 3 / g; which is also much higher than the cumulative pore volume of COF-366-Co (0.391 cm 3 / g, as shown in Figure 8 (b)). Figure 8The results show that the specific surface area and cumulative pore volume of the covalent organic framework-Bpy CoTPP-DMTP-COF prepared according to the reported method are lower than those of the covalent organic framework-CoTPP-DMTP-COF without Bpy; and the specific surface area and cumulative pore volume of CoTPP-DMTP-COF are lower than those of COF-366-Co; therefore, the specific surface area and cumulative pore volume of CoTPP-DMTP-COF are also lower than those of COF-366-Co-Bp (1.2 eq). Figure 12 The transmission electron microscope (TEM) image of COF-366-Co-Bp (1.2 eq) prepared for the example shows obvious lattice fringes with a spacing of approximately 1.75 nm, which is much larger than the interplanar spacing of COF-366-Co (0.62 nm). Figure 10 ).like Figure 15 COF-366-Co-Bp (1.2 eq) was detected in CO2-saturated 0.1 M KHCO3 electrolyte at a scan rate of 5 mV·s. -1 Linear sweep voltammetry curves and the Faraday efficiency (FE) for electrocatalytic CO production at potentials ranging from -0.5V to -1.0V are shown. CO %) curve; From the 15(a) volt-ampere curve, it can be seen that when the potential is -1.20V, the current density is 37mA / cm. 2 Higher than COF-366-Co (24mA / cm) 2 ,like Figure 13 (a)); According to 15(b) Faraday efficiency (FE) CO The FE curve shows that when the potential reaches -0.63V, its FE CO The percentage reached a peak of 91.3%, relative to COF-366-Co(FE) CO (89.6%) improved; and when the potential is between -0.63V and -0.80V, its FE CO The percentage remained above 90%, while COF-366-Co decreased rapidly with increasing potential.

[0070] The Bpy CoTPP-DMTP-COF and CoTPP-DMTP-COF can be found in the literature Angew. Chem. Int. Ed. 2024, DOI: 10.1002 / anie.202416771 and 2. J. Am. Chem. Soc. 2024, 146, 32640.

[0071] Example 3: The preparation method of the layered columnar covalent organic framework of the present invention includes the following specific steps:

[0072] S1: Place TAPP-Co (18 mg, 0.025 mmol), terephthalaldehyde (10 mg, 0.075 mmol), and Pz (4 mg, 0.05 mmol, 2 eq) in a 10 mL ampoule, add 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene, and sonicate to disperse the raw materials evenly; then add the pre-prepared scandium trifluoromethanesulfonate catalyst aqueous solution (9.1 mg dissolved in 65 μL of water, 0.284 mol / L);

[0073] S2: The above mixture was subjected to liquid nitrogen freezing and vacuum degassing treatment three times in sequence. Under vacuum, the ampoule was sealed by heating with a flame gun and placed in a 120°C oven for two days to obtain the crude product.

[0074] S3: The crude product was washed with water and acetone by filtration, and then extracted with 1,4-dioxane and acetone by Soxhlet extraction for 24 hours. After vacuum drying at 65°C for 12 hours, 16.8 mg of purple-red solid powder was obtained, with a yield of 56.5%, denoted as COF-366-Co-Pz1(2eq).

[0075] The powder X-ray diffraction pattern of the layered columnar covalent organic framework -COF-366-Co-Pz1(2eq) prepared in this embodiment is shown below. Figure 3 As shown in (b), the strongest peak diffraction intensity of COF-366-Co-Pz1 (2eq) is approximately 1090, while the strongest peak diffraction intensity of COF-366-Co is approximately 1130. Figure 2 The results show that the crystallinity of the columnar covalent organic framework decreases with increasing Pz equivalent, and may even be lower than that of COF-366-Co. Other tests and characterizations were basically consistent with those in Examples 1 and 2.

[0076] Example 4: The preparation method of the layered columnar covalent organic framework of the present invention, the specific steps are as follows:

[0077] S1: Place TAPP-Co (18 mg, 0.025 mmol), terephthalaldehyde (10 mg, 0.075 mmol), and Bp (11.7 mg, 0.075 mmol, 3 eq) in a 10 mL ampoule, add 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene, and sonicate to disperse the raw materials evenly; then add the pre-prepared scandium trifluoromethanesulfonate catalyst aqueous solution (9.1 mg dissolved in 65 μL of water, 0.284 mol / L);

[0078] S2: The above mixture was subjected to liquid nitrogen freezing and vacuum degassing treatment three times in sequence. Under vacuum, the ampoule was sealed by heating with a flame gun and placed in a 120°C oven for two days to obtain the crude product.

[0079] S3: The crude product was washed with water and acetone by filtration, and then extracted with 1,4-dioxane and acetone for 24 hours, respectively. After vacuum drying at 65°C for 12 hours, a purple-red solid powder of 18 mg was obtained, with a yield of 55%, which was recorded as COF-366-Co-Bp1(3eq).

[0080] The powder X-ray diffraction pattern of the layered covalent organic framework-COF-366-Co-Bp1(3eq) prepared in this example is shown in FIG. 2(b), which shows that the strongest peak diffraction intensity of COF-366-Co-Bp1(3eq) is about 956, which is lower than the strongest peak diffraction intensity (1130, as shown in FIG. 1(b)) of COF-366-Co. This also indicates that as the equivalent of Bp increases, the crystallinity of the layered covalent organic framework decreases, and may even be lower than that of COF-366-Co. Other tests and characterizations are basically the same as those in Example 1 and Example 2. Figure 5 Figure 2 The powder X-ray diffraction pattern of the layered covalent organic framework-COF-366-Co-Bp1(3eq) prepared in this example is shown in FIG. 2(b), which shows that the strongest peak diffraction intensity of COF-366-Co-Bp1(3eq) is about 956, which is lower than the strongest peak diffraction intensity (1130, as shown in FIG. 1(b)) of COF-366-Co. This also indicates that as the equivalent of Bp increases, the crystallinity of the layered covalent organic framework decreases, and may even be lower than that of COF-366-Co. Other tests and characterizations are basically the same as those in Example 1 and Example 2.

[0081] Example 5: A method for preparing a layered covalent organic framework according to the present application, which comprises the following steps:

[0082] S1: TAPP-Co (18 mg, 0.025 mmol), 2,5-dimethylterephthalaldehyde (12.2 mg, 0.075 mmol), and Pz (2.4 mg, 0.03 mmol) were placed in an ampoule with a volume of 10 mL, and 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added to uniformly disperse the raw materials by ultrasonic; then a previously prepared aqueous solution of scandium triflate catalyst (9.1 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0083] S2: The above-mentioned mixed system was sequentially subjected to liquid nitrogen freezing, vacuum degassing treatment for 3 times, and then the ampoule was sealed by flame gun baking for sealing under vacuum, and was placed in a 120°C oven for 2 days of standing reaction to obtain a crude product;

[0084] S3: The crude product was washed with water and acetone by filtration, and then extracted with 1,4-dioxane and acetone for 24 hours, respectively. After vacuum drying at 65°C for 12 hours, a purple-red solid powder of 18 mg was obtained, with a yield of 55%, which was recorded as COF-366-Co-Bp1(3eq).

[0085] The tests and characterizations of the layered covalent organic framework-COF-366-Co-Pz2 prepared in this example are basically the same as those in Example 1 and Example 2.

[0086] Example 6: A method for preparing a layered covalent organic framework according to the present application, which comprises the following steps:

[0087] ​S1: TAPP-Co (18 mg, 0.025 mmol), 2,5-dimethylterephthalaldehyde (12.2 mg, 0.075 mmol) and Bp (4.68 mg, 0.03 mmol) were placed in a 10 mL ampoule, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of scandium triflate catalyst (9.1 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0088] S2: The above mixed system was sequentially treated by liquid nitrogen freezing, vacuumizing and degassing for 3 times, and the ampoule was sealed by flame gun roasting under vacuum, and then was placed in a 120°C oven for 2 days to obtain a crude product;

[0089] S3: The crude product was washed by water and acetone, and then was extracted by 1,4-dioxane and acetone for 24 hours respectively, and then was dried at 65°C under vacuum for 12 hours to obtain a purple red solid powder 18.5 mg with a yield of 54.7%, which was recorded as COF-366-Co-Bp2.

[0090] The test and characterization of the pillar-layered covalent organic framework COF-366-Co-Bp2 prepared in this example were basically the same as those in Example 1 and Example 2.

[0091] Example 7: A preparation method of a pillar-layered covalent organic framework of the present application, the specific steps are as follows:

[0092] S1: TAPP-Co (18 mg, 0.025 mmol), 2,5-dimethylterephthalaldehyde (12.2 mg, 0.075 mmol) and Bp (4.68 mg, 0.03 mmol) were placed in a 10 mL ampoule, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of scandium triflate catalyst (9.1 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0093] S2: The above mixed system was sequentially treated by liquid nitrogen freezing, vacuumizing and degassing for 3 times, and the ampoule was sealed by flame gun roasting under vacuum, and then was placed in a 120°C oven for 2 days to obtain a crude product;

[0094] S3: The crude product was washed by water and acetone, and then was extracted by 1,4-dioxane and acetone for 24 hours respectively, and then was dried at 65°C under vacuum for 12 hours to obtain a purple red solid powder 18.5 mg with a yield of 54.7%, which was recorded as COF-366-Co-Bp2.

[0095] The testing and characterization of the layer-pillar type covalent organic framework-COF-366-Co-TPA prepared in this example are basically the same as those in Embodiment 1 and Embodiment 2.

[0096] Embodiment 8: A method for preparing a layer-pillar type covalent organic framework of the present application, the specific steps are as follows:

[0097] S1: Place TAPP-Co (18 mg, 0.025 mmol), 2,5-dimethyl terephthaldehyde (12.2 mg, 0.075 mmol), and TPA (5.0 mg, 0.03 mmol) in an ampoule with a volume of 10 mL, add 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene, and ultrasonically disperse the raw materials uniformly; then add the previously prepared aqueous scandium triflate catalyst solution (9.1 mg dissolved in 65 uL of water, 0.284 mol / L);

[0098] S2: The above mixed system is sequentially subjected to vacuum degassing treatment 3 times under liquid nitrogen freezing, and the ampoule is sealed by flame gun baking under vacuum, and then placed in a 120°C oven for 2 days of static reaction to obtain a crude product;

[0099] S3: The crude product is washed by water and acetone, and then extracted by 1,4-dioxane and acetone respectively for 24 hours, and then dried at 65°C under vacuum for 12 hours to obtain a purple red solid powder 17 mg with a yield of 48.5%, which is recorded as COF-366-Co-TPA1.

[0100] The testing and characterization of the layer-pillar type covalent organic framework-COF-366-Co-TPA prepared in this example are basically the same as those in Embodiment 1 and Embodiment 2.

[0101] Embodiment 9: A method for preparing a layer-pillar type covalent organic framework of the present application, the specific steps are as follows:

[0102] S1: Place TAPP-Co (18 mg, 0.025 mmol), 2,5-dimethyl terephthaldehyde (12.2 mg, 0.075 mmol), and TPA (5.0 mg, 0.03 mmol) in an ampoule with a volume of 10 mL, add 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene, and ultrasonically disperse the raw materials uniformly; then add the previously prepared aqueous scandium triflate catalyst solution (9.1 mg dissolved in 65 uL of water, 0.284 mol / L);

[0103] S2: The above mixed system is sequentially subjected to vacuum degassing treatment 3 times under liquid nitrogen freezing, and the ampoule is sealed by flame gun baking under vacuum, and then placed in a 120°C oven for 2 days of static reaction to obtain a crude product;

[0104] S3: The crude product was washed with water and acetone by suction filtration, and then extracted with 1,4-dioxane and acetone for 24 hours, respectively. After vacuum drying at 65°C for 12 hours, a purple-red solid powder 16.8 mg was obtained with a yield of 56.5%, which was recorded as COF-366-Co-Pz3.

[0105] The testing and characterization of the layer-pillar type covalent organic framework-COF-366-Co-Pz3 prepared in this example were basically consistent with those of Example 1 and Example 2.

[0106] Example 10: A method for preparing a layer-pillar type covalent organic framework of the present application, the specific steps being as follows:

[0107] S1: TAPP-Co (18 mg, 0.025 mmol), p-xylylaldehyde (10 mg, 0.075 mmol) and Pz (2.4 mg, 0.03 mmol) were placed in an ampoule with a volume of 10 mL, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of zinc triflate catalyst (6.7 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0108] S2: The above-mentioned mixed system was sequentially subjected to vacuum degassing treatment for 3 times by liquid nitrogen freezing, and the ampoule was sealed by flame gun baking for sealing under vacuum, and then was placed in a 120°C oven for 2 days of standing reaction to obtain a crude product;

[0109] S3: The crude product was washed with water and acetone by suction filtration, and then extracted with 1,4-dioxane and acetone for 24 hours, respectively. After vacuum drying at 65°C for 12 hours, a purple-red solid powder 16.8 mg was obtained with a yield of 56.5%, which was recorded as COF-366-Co-Pz3.

[0110] The testing and characterization of the layer-pillar type covalent organic framework-COF-366-Co-Pz3 prepared in this example were basically consistent with those of Example 1 and Example 2.

[0111] Example 11: A method for preparing a layer-pillar type covalent organic framework of the present application, the specific steps being as follows:

[0112] S1: TAPP-Co (18 mg, 0.025 mmol), p-xylylaldehyde (10 mg, 0.075 mmol) and Pz (2.4 mg, 0.03 mmol) were placed in an ampoule with a volume of 10 mL, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of zinc triflate catalyst (6.7 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0113] S2: The above mixed system was sequentially treated with liquid nitrogen freezing, vacuum degassing 3 times, and the ampoule was sealed by flame gun baking under vacuum. The sealed ampoule was placed in a 120°C oven for 2 days to obtain a crude product;

[0114] S3: The crude product was washed by water and acetone, and then extracted by 1,4-dioxane and acetone for 24 hours, respectively. After vacuum drying at 65°C for 12 hours, a purple red solid powder 12.6 mg was obtained, with a yield of 42%, which was recorded as COF-366-Co-Pz5.

[0115] The testing and characterization of the layer columnar covalent organic framework COF-366-Co-Pz5 prepared in this example were basically the same as those in Example 1 and Example 2.

[0116] Example 12: A preparation method of a layer columnar covalent organic framework of the present application, the specific steps are as follows:

[0117] S1: 5,10,15,20-tetrakis(4-aminophenyl)porphyrin-copper (TAPP-Cu, 18.2 mg, 0.025 mmol), p-phenylenediformaldehyde (10 mg, 0.075 mmol) and Pz (2.4 mg, 0.03 mmol) were placed in an ampoule with a volume of 10 mL, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of scandium triflate catalyst (5.8 mg dissolved in 130 uL of water, 0.09 mol / L) was added;

[0118] S2: The above mixed system was sequentially treated with liquid nitrogen freezing, vacuum degassing 3 times, and the ampoule was sealed by flame gun baking under vacuum. The sealed ampoule was placed in a 120°C oven for 2 days to obtain a crude product;

[0119] S3: The crude product was washed by water and acetone, and then extracted by 1,4-dioxane and acetone for 24 hours, respectively. After vacuum drying at 65°C for 12 hours, a purple red solid powder 12.6 mg was obtained, with a yield of 42%, which was recorded as COF-366-Co-Pz5.

[0120] The testing and characterization of the layer columnar covalent organic framework COF-366-Co-Pz5 prepared in this example were basically the same as those in Example 1 and Example 2.

[0121] Example 13: A preparation method of a layer columnar covalent organic framework of the present application, the specific steps are as follows:

[0122] S1: TAPP-Co (18 mg, 0.025 mmol), p-xylylene aldehyde (10 mg, 0.075 mmol) and 4,4'-(2,5-dimethyl-1,4-phenylene) dipyridine (DPP) (7.8 mg, 0.03 mmol) were placed in a 10 mL ampoule, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of scandium triflate catalyst (9.1 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0123] S2: The above mixed system was sequentially treated by liquid nitrogen freezing, vacuum degassing for 3 times, and the ampoule was sealed by flame gun baking under vacuum, and then was placed in a 120°C oven for 2 days to obtain a crude product;

[0124] S3: The crude product was washed by water and acetone, and then was extracted by 1,4-dioxane and acetone for 24 hours respectively, and then was dried at 65°C under vacuum for 12 hours to obtain a purple black solid powder 15.6 mg with a yield of 42%, which was recorded as COF-366-Co-DPP.

[0125] The testing and characterization of the layer column type covalent organic framework COF-366-Co-DPP prepared in this example were basically the same as those in Example 1 and Example 2.

[0126] Example 14: A method for preparing a layer column type covalent organic framework of the present application, the specific steps are as follows:

[0127] S1: 5,10,15,20-tetrakis(4-formylphenyl)porphyrin-cobalt (TFPP-Co, 19.5 mg, 0.025 mmol), p-xylylene diamine (8.1 mg, 0.075 mmol) and Pz (2.4 mg, 0.03 mmol) were placed in a 10 mL ampoule, 0.25 mL of n-butanol and 0.25 mL of o-dichlorobenzene were added, and the raw materials were uniformly dispersed by ultrasonic; then a previously prepared aqueous solution of scandium triflate catalyst (9.1 mg dissolved in 65 uL of water, 0.284 mol / L) was added;

[0128] S2: The above mixed system was sequentially treated by liquid nitrogen freezing, vacuum degassing for 3 times, and the ampoule was sealed by flame gun baking under vacuum, and then was placed in a 120°C oven for 2 days to obtain a crude product;

[0129] S3: The crude product was washed by water and acetone, and then was extracted by 1,4-dioxane and acetone for 24 hours respectively, and then was dried at 65°C under vacuum for 12 hours to obtain a purple black solid powder 15.6 mg with a yield of 42%, which was recorded as COF-366-Co-DPP.

[0130] The testing and characterization of the layer-pillared covalent organic framework-COF-366-Co-Pz6 prepared in this example are substantially consistent with those of Example 1 and Example 2.

Claims

1. A layered columnar covalent organic framework material, with the following structural formula: ； in, X or Y is C or N, and X and Y are not the same; M is a transition metal; for or ; Ar or Ar' can be one of the following: 、 、 、 ； R is an alkyl or alkoxy group; The transition metal is Co or Cu.

2. The layered columnar covalent organic framework material as described in claim 1, characterized in that... The alkyl or alkoxy group is CH3, C2H5 or OMe.

3. The method for preparing a layered columnar covalent organic framework material as described in claim 1, characterized in that... The method includes the following steps: Step 1: Mix M-Por, aromatic dialdehyde or aromatic diamine, and pillar molecules in a molar ratio of 1:2:1~2 to make the M-Por concentration 0.05 M. Then add n-butanol and o-dichlorobenzene mixture, and after ultrasonic dispersion, add catalyst. Step 2: After sequentially freezing and degassing the mixture from Step 1 with liquid nitrogen, the system is sealed to obtain the crude product. Step 3: The crude product is filtered, washed, Soxhlet extracted, and vacuum dried to obtain a columnar covalent organic framework material. The M-Por is either TAPP or TFPP.

4. The method for preparing a layered columnar covalent organic framework material as described in claim 3, characterized in that... The catalyst is Lewis acid, namely a trifluoromethanesulfonate metal salt, including scandium trifluoromethanesulfonate, zinc trifluoromethanesulfonate, iron trifluoromethanesulfonate, yttrium trifluoromethanesulfonate, and indium trifluoromethanesulfonate, with a concentration of 0.09~0.3 mol / L.

5. The method for preparing a layered columnar covalent organic framework material as described in claim 3, characterized in that... The volume ratio of the n-butanol to o-dichlorobenzene mixture is 1:

1.

6. The method for preparing a layered columnar covalent organic framework material as described in claim 3, characterized in that... The crude product was washed with water and acetone by filtration, then extracted with 1,4-dioxane and acetone by Soxhlet extraction for 24 hours, and dried under vacuum at 65 °C for 12 hours to obtain a columnar covalent organic framework material.

7. The layered columnar covalent organic framework material as described in claim 1 is applied to the electrocatalytic reduction of carbon dioxide.

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