Ternary rare earth metal alloy particle (at) porphyrin COF mimic enzyme as well as preparation method and application thereof

Abstract

The invention provides a preparation method and application of a ternary rare earth metal alloy particle (at) porphyrin COF mimic enzyme. The preparation method comprises the following steps: suspending porphyrin COF in an ethanol solution containing ternary rare earth metal ions M13 < + >, M23 < 3 + > and M33 < 3 + >, and carrying out a stirring reaction in an N2 atmosphere; after stirring is completed, suction filtration and ethanol washing are conducted, and porphyrin COF solids adsorbed with ternary rare earth metal ions are obtained. And suspending in absolute ethyl alcohol, dropwise adding a NaBH4 ethanol solution while stirring, carrying out stirring reaction in a dark place, centrifuging the suspension, washing with ethanol and deionized water, and carrying out vacuum drying to obtain the mimic enzyme. The invention also provides application of the mimic enzyme in visible light driven CO2 reduction preparation of ethylene. The method adopts room-temperature reaction, takes visible light as an energy source and water as a solvent and a hydrogen source, is green and environment-friendly, high in reduction product generation efficiency and high in ethylene selectivity, and is a green, efficient and practical method for preparing ethylene through CO2 reduction.

Description

Technical Field

[0001] This invention belongs to the fields of industrial and biomimetic catalysis, specifically relating to a ternary rare earth metal alloy particle@porphyrin COF enzyme, its preparation method, and its application. Background Technology

[0002] The chemical industry is one of the important basic and pillar industries of the national economy. It provides essential raw materials for the development of agriculture, energy, materials, and pharmaceuticals, promotes technological innovation and industrial upgrading, provides strong support for the integrity of the national industrial system, and ensures people's normal lives. As of 2025, the total output value of China's chemical industry will account for approximately 12% of the national GDP and more than 40% of the global chemical market, making it a veritable pillar industry. Currently, organic chemicals account for a large proportion of the chemical industry. The raw materials, catalysts, solvents, additives, and products used are all based on carbon. However, the carbon in organic chemicals mainly comes from fossil resources such as coal, oil, and natural gas. Not only is carbon non-renewable, but it also flows in one direction, ultimately being emitted into the atmosphere as carbon dioxide (CO2), causing a serious greenhouse effect. Given the current chemical industry's over-reliance on non-renewable fossil resources and the environmental problems caused by CO2 emissions, converting CO2 into organic chemical raw materials or intermediates could not only alleviate the environmental problems caused by CO2 emissions and help achieve "carbon peaking and carbon neutrality," but also provide new "carbon resources" for the development of organic chemicals, avoid the chemical industry's dependence on non-renewable fossil resources, realize the recycling of carbon elements, and promote sustainable social development, which has great economic value and social significance.

[0003] The conversion of carbon dioxide (CO2) into chemical raw materials or intermediates is currently mainly achieved through catalytic reduction. Reduction products include carbon monoxide (CO), methane (CH4), methanol (CH3OH), formic acid (HCOOH), ethylene (CH2=CH2), ethane (CH3-CH3), and ethanol (CH3CH2OH), all of which are important chemical raw materials and intermediates. To achieve this conversion, various catalytic methods can be employed, including thermal catalysis, electrocatalysis, photocatalysis, biocatalysis, photothermal catalysis, photoelectrocatalysis, and photoenzyme catalysis. Among these, visible light-driven CO2 catalytic reduction uses solar energy as its primary energy source, eliminating reliance on non-renewable resources such as fossil fuels. This effectively alleviates energy shortages and reduces the over-exploitation and use of traditional energy sources. Ethylene, one of the most basic raw materials in the chemical industry, is a key ingredient in the production of polyethylene, ethylene glycol, and other chemical products, and is widely used in the plastics, fiber, and rubber industries. Ethylene production is a significant indicator of a country's petrochemical development level. In 2024, my country's ethylene production approached 35 million tons. If all of this ethylene production came from CO2, it would consume nearly 110 million tons of CO2. Therefore, visible light-driven CO2 reduction to produce ethylene can not only effectively utilize industrial by-product CO2 and mitigate the greenhouse effect, but also provide a new "carbon source" for the chemical industry, promoting carbon cycling and sustainable social development.

[0004] Although visible light-driven CO2 reduction to produce ethylene is a promising approach to efficiently utilize CO2, mitigate its greenhouse effect, achieve carbon neutrality, carbon peaking, and carbon cycling, and provide a new carbon source for the chemical industry, thus realizing sustainable social development, visible light-driven CO2 catalytic reduction to produce ethylene generally suffers from low conversion efficiency and a large gap between its performance and practical application requirements.

[0005] Therefore, developing efficient visible light photocatalytic pathways to achieve efficient CO2 reduction with industrial application value and generate ethylene is an urgent need of the chemical industry and an inevitable path for sustainable social development. Summary of the Invention

[0006] In order to overcome the shortcomings of existing visible light-driven CO2 catalytic reduction technology for ethylene production, the present invention aims to provide a ternary rare earth metal alloy particle@porphyrin COF enzyme (M1M2M3-COF), its preparation method, and its application as a catalyst in the reduction of carbon dioxide (CO2) to ethylene.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows: In a first aspect, the present invention provides a method for preparing ternary rare earth metal alloy particles@porphyrin COF enzyme-mimicking enzyme, comprising the following steps: (1) Porphyrin COF is suspended in a medium containing ternary rare earth metal ions M1 3+ M2 3+ M3 3+ In an ethanol solution, under a N2 atmosphere, the mixture was stirred at 0 °C ~ 60 °C for 1.0 h ~ 12.0 h. (2) The reaction mixture was filtered and washed with ethanol to obtain M1 with adsorbed ternary rare earth metal ions. 3+ M2 3+ M3 3+ porphyrin COF solid; (3) The adsorbed ternary rare earth metal ions M1 3+ M2 3+ M3 3+ The porphyrin COF solid was suspended in anhydrous ethanol. Under N2 atmosphere, freshly prepared NaBH4 ethanol solution of 0.01 mol / L to 1.00 mol / L was added dropwise with stirring at 0 °C to 60 °C. The mixture was stirred at 700 rpm in the dark for 3.0 h to 24.0 h to obtain a suspension. (4) The suspension was centrifuged, washed with ethanol and deionized water, and dried under vacuum at 80 °C to obtain ternary rare earth metal alloy particles @porphyrin COF enzyme (M1M2M3-COF).

[0008] Furthermore, in step (1), the ternary rare earth metal ions M1 3+ M2 3+ M3 3+ The molar concentrations in the ethanol solution ranged from 0.01 mol / L to 2.00 mol / L; among which, rare earth metal ions M1 3+ and M2 3+ The molar concentration ratio is 1:0.01~1:100; rare earth metal ions M1 3+ and M3 3+ The molar concentration ratio is 1:0.01~1:100.

[0009] Furthermore, the ternary rare earth metal ions M1 in step (1) 3+ M2 3+ M3 3+ The ratio of the total molar amount to the molar amount of NaBH4 mentioned in step (3) is 1:1 to 1:50.

[0010] Further, in step (1), the mass ratio of porphyrin COF to the volume of the ethanol solution is 1:10~1:500; in step (3), ternary rare earth metal ions M1 are adsorbed. 3+ M2 3+ M3 3+The mass ratio of the porphyrin COF solid to the volume of the ethanol solution is 1:10~1:500. Further, the ternary rare earth metal ion M1... 3+ M2 3+ M3 3+ For La 3+ Ce 3+ Pr 3+ 、 Nd 3+ Sm 3 + Eu 3+ The three different ternary rare earth metal ions are provided by the corresponding metal salts; the metal salts are selected from chlorides, sulfates, nitrates and their hydrates.

[0011] In a second aspect, the present invention provides ternary rare earth metal alloy particles@porphyrin COF enzymes prepared by the preparation method described in the first aspect.

[0012] Thirdly, this invention provides the application of the ternary rare earth metal alloy particles @porphyrin COF enzyme as described in the second invention in the visible light-driven reduction of carbon dioxide (CO2) to prepare ethylene. Specifically, the application involves dispersing the ternary rare earth metal alloy particles @porphyrin COF enzyme in deionized water, introducing CO2 into the reactor to replace the air, adjusting the CO2 pressure to 0.05 MPa~0.10 MPa, turning on a 10 W~500 W LED incandescent visible light source, and stirring the reaction. The mass ratio of the ternary rare earth metal alloy particles @porphyrin COF enzyme to deionized water in the CO2 reduction reaction is 1:100~1:100000.

[0013] Furthermore, the reduction products of the application are ethylene, carbon monoxide, and methane.

[0014] The beneficial effects of this invention are as follows: This invention uses ternary rare earth metal alloy particles@porphyrin COF enzyme (M1M2M3-COF) as a catalyst for the reduction of CO2 to prepare ethylene. The catalyst has an ingenious design, novel structure, stable properties, low cost, and wide range of applications.

[0015] In the CO2 reduction to ethylene reaction, the reduction product generation efficiency is high, which has the potential for industrial application; the ethylene selectivity is high, which effectively reduces the energy consumption, carbon emissions and cost input caused by the separation of reduction products; the CO2 reduction to ethylene reaction of this invention uses visible light as the energy source, water as the solvent and hydrogen source, the reaction is carried out at room temperature, the conditions are mild, the operation is safe, the energy consumption is low, no organic solvents are used, energy saving and emission reduction are achieved, and the potential for industrial application is great.

[0016] This invention provides a biomimetic catalytic method for the efficient reduction of CO2 to ethylene, and also offers guidance for improving the catalytic efficiency of other catalytic systems. It represents a green, efficient, and practical technology for the reduction of CO2 to ethylene. Detailed Implementation

[0017] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0018] This invention achieves highly efficient catalytic reduction of CO2 to ethylene by mimicking natural enzymes. A biomimetic catalytic system with synergistic dual-catalytic-center action is constructed using a ternary rare-earth metal alloy cluster as the catalytic active center and by controlling the spacing and electronic effects between the metal centers. This system catalyzes the conversion of CO2 to C2 products. The large conjugated structure of the porphyrin-based COF promotes electron transport and visible light absorption during CO2 reduction, thereby promoting CC-C coupling and ethylene production. The cavity structure of the porphyrin-based COF mimics the hydrophobic pocket of an enzyme, providing a site for the enrichment and reaction of hydrophobic species during CO2 reduction, further promoting CC-C coupling and C2 product formation. The visible light-driven CO2 reduction method for ethylene production provided by this invention operates at room temperature, using visible light as the energy source and water as the solvent. It is not only environmentally friendly and energy-saving, but also exhibits high efficiency in reducing the reduction product, high ethylene selectivity, and strong practicality. It is a green, efficient, and practical method for CO2 reduction to ethylene production.

[0019] Examples 1-12 describe the preparation of ternary rare earth metal alloy particles@porphyrin COF enzymes; Examples 13-28 illustrate the application of ternary rare earth metal alloy particles@porphyrin COF enzymes in the visible light-driven reduction of carbon dioxide (CO2) to produce ethylene.

[0020] The preparation method of porphyrin COF in the following examples is as follows: 4-acetaminobenzaldehyde was suspended in a propionic acid solution, and pyrrole was added under a N2 atmosphere. The mixture was stirred at 100 °C to 150 °C for 2.0 h to 6.0 h. After stirring, the reaction mixture was filtered and washed with methanol to obtain 5,10,15,20-(4-acetylphenyl)porphyrin. 5,10,15,20-(4-acetylphenyl)porphyrin was dissolved in trifluoroacetic acid and distilled water, purged with N2, and stirred at 75 °C to 100 °C for 12.0 h to 24.0 h. After stirring, the reaction mixture was neutralized, extracted, rotary evaporated, and dried under vacuum to obtain 5,10,15,20-(4-aminophenyl)porphyrin. 5,10,15,20-(4-aminophenyl)porphyrin and 2,5-dihydroxyterephthalaldehyde were added to a Pyrex glass tube, followed by the addition of n-butanol, 1,2-dichlorobenzene, and a 6M aqueous solution of acetic acid. The tube was rapidly frozen at 77 K, evacuated, and then heated in an oven at 120 °C for 72.0 h. After the reaction was complete, the crystalline solid was separated by centrifugation, washed with tetrahydrofuran and acetone, and dried under vacuum at 80 °C to obtain porphyrin COF.

[0021] Nomenclature rules for ternary rare earth metal alloy particles @ porphyrin COF enzyme-mimicking catalysts. M1M2M3-COF@0.5M@0.5M@0.5M@0.2M@150@25@2h@25@12h, representing the rare earth metal ions M1 during sample preparation. 3+ The molar concentration is 0.5 mol / L, M2 3+ The molar concentration is 0.5 mol / L, M3 3+ The molar concentration of COF was 0.5 mol / L; the concentration of sodium borohydride was 0.2 mol / L; the mass ratio of COF to the volume of the ethanol solution was 150; the reaction was carried out by stirring at 25 °C for 2 h; and the reduction reaction was carried out at 25 °C for 12 h.

[0022] Example 1 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing La 3+ The molar concentration is 0.1 mol / L, Ce 3+ The molar concentration is 0.1 mol / L, Pr 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, 30 mL of freshly prepared NaBH4 ethanol solution (0.2 mol / L) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.6532 g of a pale yellow solid. The obtained material was named LaCePr-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0023] Example 2 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing La 3+ The molar concentration is 0.01 mol / L, Ce 3+ The molar concentration is 0.01 mol / L, Pr 3+ The mixture was stirred in 150 mL of a 0.01 mol / L ethanol solution at 25 °C for 2.0 h under a N2 atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 0.2 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.6213 g of a pale yellow solid. The obtained material was named LaCePr-COF@0.01M@0.01M@0.01M@0.2M@150@25@2h@25@12h.

[0024] Example 3 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing La 3+ The molar concentration is 1 mol / L, Ce 3+ With a molar concentration of 1 mol / L, Pr 3+ The mixture was stirred in 150 mL of a 1 mol / L ethanol solution at 25 °C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La.3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 0.2 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.6014 g of a pale yellow solid. The obtained material was named LaCePr-COF@1M@1M@1M@0.2M@150@25@2h@25@12h.

[0025] Example 4 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing La 3+ The molar concentration is 0.1 mol / L, Ce 3+ The molar concentration is 0.1 mol / L, Pr 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The mixture was stirred at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.6089 g of a pale yellow solid. The obtained material was named LaCePr-COF@0.1M@0.1M@0.1M@0.01M@150@25@2h@25@12h.

[0026] Example 5 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing La 3+ The molar concentration is 0.1 mol / L, Ce 3+ The molar concentration is 0.1 mol / L, Pr3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 1 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.5634 g of a pale yellow solid. The obtained material was named LaCePr-COF@0.1M@0.1M@0.1M@1M@150@25@2h@25@12h.

[0027] Example 6 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing La 3+ The molar concentration is 0.1 mol / L, Ce 3+ The molar concentration is 0.1 mol / L, Sm 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 0.2 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.6034 g of a pale yellow solid. The obtained material was named LaCeSm-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0028] Example 7 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing La 3+ The molar concentration is 0.1 mol / L, Nd 3+ The molar concentration is 0.1 mol / L, Eu 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 0.2 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.6072 g of a pale yellow solid. The obtained material was named LaNdEu-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0029] Example 8 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing Ce. 3+ The molar concentration is 0.1 mol / L, Pr 3+ The molar concentration is 0.1 mol / L, Eu 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 0.2 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.5835 g of a pale yellow solid. The obtained material was named CePrEu-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0030] Example 9 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing Ce. 3+ The molar concentration is 0.1 mol / L, Nd 3+ The molar concentration is 0.1 mol / L, Sm 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 0.2 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.5976 g of a pale yellow solid. The obtained material was named CeNdSm-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0031] Example 10 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing Pr 3+ The molar concentration is 0.1 mol / L, Nd 3+ The molar concentration is 0.1 mol / L, Sm 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, 30 mL of freshly prepared NaBH4 ethanol solution (0.2 mol / L) was added dropwise with stirring at 25 °C. The mixture was stirred at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.5924 g of a pale yellow solid. The obtained material was named PrNdSm-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0032] Example 11 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing Pr 3+ The molar concentration is 0.1 mol / L, Sm 3+ The molar concentration is 0.1 mol / L, Eu 3+ The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, 0.2 mol / L freshly prepared NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.6124 g of a pale yellow solid. The obtained material was named PrSmEu-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0033] Example 12 In a 500 mL single-necked flask, porphyrin COF (1.00 g) was suspended in a solution containing Nd... 3+ The molar concentration is 0.1 mol / L, Sm 3+ The molar concentration is 0.1 mol / L, Eu 3+The mixture was stirred in 150 mL of a 0.1 mol / L ethanol solution at 25°C for 2.0 h under a nitrogen atmosphere. After stirring, the reaction mixture was filtered and washed with 3 × 20 mL of ethanol to obtain the product containing adsorbed La. 3+ Ce 3+ Pr 3+ Porphyrin COF solid. Adsorbed with La 3+ Ce 3+ Pr 3+ The porphyrin COF solid was suspended in anhydrous ethanol (80 mL). Under a nitrogen atmosphere, a freshly prepared 0.2 mol / L NaBH4 ethanol solution (30 mL) was added dropwise with stirring at 25 °C. The reaction was carried out at 700 rpm in the dark for 12.0 h. The resulting suspension was centrifuged, washed with 3 × 20 mL of ethanol, washed with 5 × 20 mL of deionized water, and dried at 80 °C for 8.0 h to obtain 0.5914 g of a pale yellow solid. The obtained material was named NdSmEu-COF@0.1M@0.1M@0.1M@0.2M@150@25@2h@25@12h.

[0034] Table 1 Summary of Examples 1-12 for the Preparation of Ternary Rare Earth Metal Alloy Particles@Porphyrin COF Enzyme-like Catalysts Example 13 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was stirred at room temperature for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 684.23 μmol / (g). Cat. ·h), of which ethylene selectivity is 93%, carbon monoxide selectivity is 4%, and methane selectivity is 3%.

[0035] Example 14 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 10 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 554.98 μmol / (g). Cat. (·h), of which ethylene selectivity is 87%, carbon monoxide selectivity is 5%, and methane selectivity is 8%.

[0036] Example 15 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 1 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 334.12 μmol / (g). Cat. ·h), of which ethylene selectivity is 88%, carbon monoxide selectivity is 8%, and methane selectivity is 4%.

[0037] Example 16 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 100 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was stirred at room temperature for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 336.31 μmol / (g). Cat. ·h), of which ethylene selectivity is 90%, carbon monoxide selectivity is 5%, and methane selectivity is 5%.

[0038] Example 17 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.08 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 434.87 μmol / (g). Cat. ·h), of which ethylene selectivity is 90%, carbon monoxide selectivity is 6%, and methane selectivity is 4%.

[0039] Example 18 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.01M, 0.01M, 0.01M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.05 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 234.87 μmol / (g). Cat. ·h), of which ethylene selectivity is 67%, carbon monoxide selectivity is 23%, and methane selectivity is 10%.

[0040] Example 19 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF@1M@1M@1M@0.2M@150@25@2h@25@12h catalyst was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 10 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 437.98 μmol / (g). Cat. (·h), of which ethylene selectivity is 79%, carbon monoxide selectivity is 7%, and methane selectivity is 14%.

[0041] Example 20 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.1M, 0.1M, 0.01M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 100 W LED incandescent light source was turned on, and the reaction was stirred at room temperature for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 435.78 μmol / (g). Cat. (·h), of which ethylene selectivity is 81%, carbon monoxide selectivity is 9%, and methane selectivity is 10%.

[0042] Example 21 In a CO2 photocatalytic reactor, 10 mg of LaCePr-COF catalyst (0.1M) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 500 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 424.97 μmol / (g). Cat. (·h), of which ethylene selectivity is 78%, carbon monoxide selectivity is 13%, and methane selectivity is 9%.

[0043] Example 22 In a CO2 photocatalytic reactor, 10 mg of LaCeSm-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was stirred at room temperature for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 523.96 μmol / (g). Cat. ·h), of which ethylene selectivity is 89%, carbon monoxide selectivity is 8%, and methane selectivity is 3%.

[0044] Example 23 In a CO2 photocatalytic reactor, 10 mg of LaNdEu-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 547.49 μmol / (g). Cat. ·h), of which ethylene selectivity is 87%, carbon monoxide selectivity is 4%, and methane selectivity is 9%.

[0045] Example 24 In a CO2 photocatalytic reactor, 10 mg of CePrEu-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was stirred at room temperature for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 524.12 μmol / (g). Cat. ·h), of which ethylene selectivity is 87%, carbon monoxide selectivity is 4%, and methane selectivity is 9%.

[0046] Example 25 In a CO2 photocatalytic reactor, 10 mg of CeNdSm-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 457.92 μmol / (g). Cat. ·h), of which ethylene selectivity is 84%, carbon monoxide selectivity is 4%, and methane selectivity is 6%.

[0047] Example 26 In a CO2 photocatalytic reactor, 10 mg of PrNdSm-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 432.96 μmol / (g). Cat. (·h), of which ethylene selectivity is 82%, carbon monoxide selectivity is 8%, and methane selectivity is 10%.

[0048] Example 27 In a CO2 photocatalytic reactor, 10 mg of PrSmEu-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was stirred at room temperature for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 524.97 μmol / (g). Cat. (·h), of which ethylene selectivity is 88%, carbon monoxide selectivity is 5%, and methane selectivity is 7%.

[0049] Example 28 In a CO2 photocatalytic reactor, 10 mg of NdSmEu-COF catalyst (0.1M, 0.1M, 0.1M, 0.2M, 150, 25, 2h, 25, 12h) was dispersed in 50 g of deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.09 MPa. The reactor was then sealed. A 200 W LED incandescent light source was turned on, and the reaction was carried out at room temperature with stirring for 8.0 h. The reduction products were detected by online gas chromatography, and the overall reduction product formation efficiency was 512.74 μmol / (g). Cat. (·h), of which ethylene selectivity is 87%, carbon monoxide selectivity is 3%, and methane selectivity is 10%.

[0050] Table 2. Performance of ternary rare earth metal alloy particles@porphyrin COF enzyme-mimicking enzyme in CO2 reduction to ethylene. As shown in Table 2, the LaCePr ternary rare earth metal@porphyrin COF prepared in Example 1 exhibits the best performance under the application conditions described in Example 13, with a total reduction product formation efficiency of 684.23 μmol / (g). Cat. ·h), of which the ethylene selectivity is 93%.

[0051] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for preparing a ternary rare earth metal alloy particle@porphyrin COF enzyme, characterized in that, Includes the following steps: (1) Porphyrin COF is suspended in a medium containing ternary rare earth metal ions M1 3+ M2 3+ M3 3+ In an ethanol solution, under a N2 atmosphere, the mixture was stirred at 0 °C ~ 60 °C for 1.0 h ~ 12.0 h. (2) The reaction mixture was filtered and washed with ethanol to obtain M1 with adsorbed ternary rare earth metal ions. 3+ M2 3+ M3 3+ porphyrin COF solid; (3) The adsorbed ternary rare earth metal ions M1 3+ M2 3+ M3 3+ The porphyrin COF solid was suspended in anhydrous ethanol. Under N2 atmosphere, freshly prepared NaBH4 ethanol solution of 0.01 mol / L to 1.00 mol / L was added dropwise with stirring at 0 °C to 60 °C. The mixture was stirred at 700 rpm in the dark for 3.0 h to 24.0 h to obtain a suspension. (4) The suspension was centrifuged, washed with ethanol and deionized water, and dried under vacuum at 80 °C to obtain ternary rare earth metal alloy particles @porphyrin COF enzyme.

2. The preparation method according to claim 1, characterized in that, In step (1), the ternary rare earth metal ion M1 3 + M2 3+ M3 3+ The molar concentrations in the ethanol solution ranged from 0.01 mol / L to 2.00 mol / L; among which rare earth metal ions M1 3+ and M2 3+ The molar concentration ratio is 1:0.01~1:100; rare earth metal ions M1 3+ and M3 3+ The molar concentration ratio is 1:0.01~1:

100.

3. The preparation method according to claim 1, characterized in that, The ternary rare earth metal ions M1 in step (1) 3+ M2 3+ M3 3+ The ratio of the total molar amount to the molar amount of NaBH4 mentioned in step (3) is 1:1 to 1:

50.

4. The preparation method according to claim 1, characterized in that, In step (1), the mass ratio of porphyrin COF to the volume of ethanol solution is 1:10~1:500; in step (3), ternary rare earth metal ions M1 are adsorbed. 3+ M2 3+ M3 3+ The ratio of the mass of porphyrin COF solid to the volume of ethanol solution is 1:10~1:

500.

5. The preparation method according to claim 1, characterized in that, The ternary rare earth metal ion M1 3+ M2 3+ M3 3+ For La 3+ Ce 3+ Pr 3+ 、 Nd 3+ Sm 3+ Eu 3+ There are three different types.

6. The preparation method according to claim 5, characterized in that, The ternary rare earth metal ions are provided by the corresponding metal salts; the metal salts are selected from chlorides, sulfates, nitrates and their hydrates.

7. A ternary rare earth metal alloy particle@porphyrin COF enzyme prepared by the preparation method according to any one of claims 1 to 6.

8. The application of the ternary rare earth metal alloy particles @porphyrin COF enzyme as described in claim 7 in the visible light-driven reduction of carbon dioxide (CO2) to prepare ethylene.

9. The application according to claim 8, characterized in that, The specific application method is as follows: Ternary rare earth metal alloy particles@porphyrin COF enzyme were dispersed in deionized water. CO2 was introduced into the reactor to replace the air, and the CO2 pressure was adjusted to 0.05 MPa~0.10 MPa. A 10 W~500 W LED incandescent light source was turned on, and the reaction was stirred. The mass ratio of ternary rare earth metal alloy particles@porphyrin COF enzyme to deionized water in the CO2 reduction reaction was 1:100~1:100000.

10. The application according to claim 9, characterized in that, The reduction products of the application are ethylene, carbon monoxide, and methane.

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