A supported ZrO2-Fe2O3 photocatalyst and its preparation method
By modifying molecular sieves and loading nano-ZrO2-Fe2O3 to form a heterojunction structure, the problem of easy aggregation of ZrO2-Fe2O3 photocatalysts is solved, and the photocatalytic performance is improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- LIAONING INST OF SCI & TECH
- Filing Date
- 2025-11-13
- Publication Date
- 2026-06-19
AI Technical Summary
ZrO2-Fe2O3 photocatalysts are prone to aggregation and have poor photocatalytic degradation performance.
Molecular sieves were modified with bis(3-hydroxytyramine) modifier, and nano-ZrO2 and Fe2O3 were loaded onto the molecular sieves through hydrothermal reaction to form a heterojunction structure, which promoted the separation of photogenerated electrons and reduced recombination.
Uniform dispersion of nano-ZrO2 and Fe2O3 was achieved, increasing the number of photocatalytic active sites and improving the degradation rate of methylene blue, rhodamine B and tetracycline hydrochloride.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of photocatalyst technology, specifically to a supported ZrO2-Fe2O3 photocatalyst and its preparation method. Background Technology
[0002] In recent years, my country's industry has developed rapidly, but this has also generated a large amount of industrial wastewater. This wastewater contains a large amount of organic pollutants such as dyes and antibiotics, as well as inorganic pollutants such as heavy metals and inorganic salts. Among these, organic pollutants are difficult to degrade naturally and are highly toxic; if not effectively treated, they can cause serious environmental pollution. Photocatalytic degradation technology utilizes diverse and environmentally friendly catalysts with high degradation efficiency and has already achieved widespread practical application.
[0003] Iron oxide is inexpensive, readily available, non-toxic, and environmentally friendly, and possesses certain photocatalytic properties, making it an important material for photocatalytic degradation. Combining iron oxide with nano-zinc oxide, nano-zirconia, tin dioxide, and other materials can form heterojunction structures, resulting in higher photocatalytic activity. However, photocatalysts such as iron oxide and zirconium oxide are prone to aggregation, leading to a reduction in photocatalytic sites and consequently lower photocatalytic degradation performance. Supporting photocatalysts with molecular sieves, alumina, or other materials effectively addresses this issue. Summary of the Invention
[0004] This invention solves the problem that ZrO2-Fe2O3 photocatalysts are prone to agglomeration and have poor photocatalytic degradation performance.
[0005] Technical Solution: A method for preparing a supported ZrO2-Fe2O3 photocatalyst
[0006] (1) Nitrogen gas is introduced into the flask, and N,N-dimethylformamide, acid anhydride monomer, dopamine hydrochloride and triethylamine are added. After the reaction, the mixture is filtered, the filtrate is concentrated under reduced pressure, ethanol is added to dissolve it, and then chloroform is added to precipitate it. The mixture is filtered and the precipitate is dried to obtain bis(3-hydroxytyramine) modifier.
[0007] (2) Add water, molecular sieve, and bis(3-hydroxytyramine) modifier to the flask, stir to modify, filter, wash with water, and dry to obtain molecular sieve carrier.
[0008] (3) Add water, molecular sieve support and nano ZrO2 to the flask, stir to load, filter and dry to obtain molecular sieve loaded ZrO2.
[0009] (4) Add water, iron salt, and sodium hydroxide aqueous solution to the hydrothermal reactor, stir and add molecular sieve-supported ZrO2, react, filter, wash with water, and dry to obtain supported ZrO2-Fe2O3 photocatalyst.
[0010] Furthermore, in (1), the anhydride monomer is ethylenediaminetetraacetic anhydride or diethylenetriaminepentaacetic anhydride.
[0011] Furthermore, in (1), the reaction temperature is 70-75℃ and the reaction time is 18-24h.
[0012] Furthermore, in (2), the ratio of molecular sieve to bis(3-hydroxytyramine) modifier is 100g: (5-20)g.
[0013] Furthermore, in (2), the temperature during modification is 20-60℃ and the time is 2-5h.
[0014] Furthermore, in (3), the ratio of molecular sieve carrier to nano ZrO2 is 100g: (4-15).
[0015] Furthermore, in (3), the temperature during the loading of the stirring is 20-40℃ and the time is 2-3h.
[0016] Furthermore, in (4), the ratio of iron salt, sodium hydroxide, and molecular sieve-loaded ZrO2 is (12-40)g:(6-32)g:100g.
[0017] Furthermore, (4) the ferric salt is ferric chloride or ferric nitrate.
[0018] Furthermore, in (4), the reaction temperature is 140-180℃ and the reaction time is 18-24h.
[0019] The beneficial technical effects of this invention are as follows: The bis(3-hydroxytyramine) modifier of this invention contains multiple carboxyl groups, which can more effectively modify the surface of molecular sieves and serve as a carrier for photocatalysts. The molecular sieve incorporates a large number of catechol structures, forming coordination interactions with the ZrO2 surface, allowing nano-ZrO2 to be uniformly loaded onto the molecular sieve surface. Simultaneously, the large number of carboxyl groups enhance the Fe... 3+ Forming a complex, Fe 3+ Adsorbed onto the surface of the molecular sieve, the generated nano-Fe2O3 is uniformly distributed in the molecular sieve matrix after a hydrothermal high-temperature reaction. The nano-ZrO2 and Fe2O3 are uniformly dispersed and do not easily agglomerate, thus having more photocatalytic active sites. The two form an interfacial coupling heterojunction, which can promote the separation of photogenerated electrons from ZrO2 and Fe2O3, reduce the recombination of photogenerated electrons and holes, and generate a large number of photogenerated electrons and free radicals, which play a good role in the redox degradation of methylene blue, rhodamine B, and tetracycline hydrochloride.
[0020] The molecular sieve of this invention has a large specific surface area. At the same time, the introduced carboxyl groups have electrostatic interactions with the cationic groups of methylene blue and rhodamine B, and the introduced phenolic hydroxyl groups form hydrogen bonds with tetracycline hydrochloride containing phenolic hydroxyl groups, resulting in higher affinity. This promotes the adsorption of methylene blue, rhodamine B, and tetracycline hydrochloride onto the surface of the catalyst molecular sieve, which can accelerate their catalytic degradation and achieve a higher degradation rate. Detailed Implementation
[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0022] Nitrogen gas was introduced into a flask, followed by the addition of 60 mL of N,N-dimethylformamide, 2.54 g of ethylenediaminetetraacetic acid dianhydride, 3.78 g of dopamine hydrochloride, and 2.8 mL of triethylamine. The mixture was heated to 70 °C and stirred for 18 h. After filtration, the filtrate was concentrated under reduced pressure, dissolved in ethanol, and then precipitated with chloroform. The precipitate was filtered and dried to obtain bis(3-hydroxytyramine) modifier A, with the structural formula [insert structural formula here]. .
[0023] Nitrogen gas was bubbled into a flask, and 50 mL of N,N-dimethylformamide, 0.85 g of diethylenetriaminepentaacetic acid dianhydride, 0.99 g of dopamine hydrochloride, and 0.74 mL of triethylamine were added. The mixture was heated to 70-75 °C and stirred for 18-24 h. After filtration, the filtrate was concentrated under reduced pressure, dissolved in ethanol, and then precipitated with chloroform. The precipitate was filtered and dried to obtain bis(3-hydroxytyramine) modifier B, with the structural formula [insert structural formula here]. .
[0024] Example 1:
[0025] (1) Add 300 mL of water, 20 g of ZSM-5 molecular sieve, and 1 g of bis(3-hydroxytyramine) modifier A to a flask, stir and modify at 30 °C for 2 h, filter, wash with water, and dry to obtain molecular sieve carrier.
[0026] (2) Add 400 mL of water, 20 g of molecular sieve support and 0.8 g of nano ZrO2 to the flask, stir and load at 30 °C for 2 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0027] (3) Add 400 mL of water, 12 g of ferric chloride, and 30 mL of aqueous solution containing 9.6 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 160 °C for 24 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0028] Example 2:
[0029] (1) Add 300 mL of water, 20 g of ZSM-5 molecular sieve, and 2.3 g of bis(3-hydroxytyramine) modifier B to a flask, stir and modify at 20 °C for 5 h, filter, wash with water, and dry to obtain molecular sieve carrier.
[0030] (2) Add 500 mL of water, 20 g of molecular sieve support and 1.5 g of nano ZrO2 to the flask, stir and load at 40 °C for 2 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0031] (3) Add 550 mL of water, 9.4 g of ferric chloride, and 20 mL of aqueous solution containing 7.5 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 140 °C for 24 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0032] Example 3:
[0033] (1) Add 400 mL of water, 20 g of ZSM-5 molecular sieve, and 2.8 g of bis(3-hydroxytyramine) modifier A to a flask, stir and modify at 60 °C for 3 h, filter, wash with water, and dry to obtain molecular sieve carrier.
[0034] (2) Add 500 mL of water, 20 g of molecular sieve support and 2.2 g of nano ZrO2 to the flask, stir and load at 20 °C for 3 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0035] (3) Add 500 mL of water, 6.7 g of ferric chloride, and 15 mL of aqueous solution containing 5.4 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 180 °C for 18 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0036] Example 4:
[0037] (1) Add 400 mL of water, 20 g of ZSM-5 molecular sieve, and 4 g of bis(3-hydroxytyramine) modifier A to a flask, stir and modify at 40 °C for 5 h, filter, wash with water, and dry to obtain molecular sieve carrier.
[0038] (2) Add 500 mL of water, 20 g of molecular sieve support and 3 g of nano ZrO2 to the flask, stir and load at 20 °C for 3 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0039] (3) Add 550 mL of water, 3.6 g of ferric nitrate, and 10 mL of aqueous solution containing 1.8 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 180 °C for 18 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0040] Comparative Example 1
[0041] (1) Add 400 mL of water, 20 g of ZSM-5 molecular sieve and 0.8 g of nano ZrO2 to a flask, stir and load at 30 °C for 2 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0042] (2) Add 400 mL of water, 12 g of ferric chloride, and 30 mL of aqueous solution containing 9.6 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 160 °C for 24 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0043] Comparative Example 2
[0044] (1) Add 300 mL of water, 20 g of ZSM-5 molecular sieve and 1 g of ethylenediaminetetraacetic acid to a flask, stir and modify at 30 °C for 2 h, filter, wash with water and dry to obtain molecular sieve carrier.
[0045] (2) Add 400 mL of water, 20 g of molecular sieve support and 0.8 g of nano ZrO2 to the flask, stir and load at 30 °C for 2 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0046] (3) Add 400 mL of water, 12 g of ferric chloride, and 30 mL of aqueous solution containing 9.6 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 160 °C for 24 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0047] Comparative Example 3
[0048] (1) Add 300 mL of water, 20 g of ZSM-5 molecular sieve and 1 g of dopamine hydrochloride to a flask, stir and modify at 30 °C for 2 h, filter, wash with water and dry to obtain molecular sieve carrier.
[0049] (2) Add 400 mL of water, 20 g of molecular sieve support and 0.8 g of nano ZrO2 to the flask, stir and load at 30 °C for 2 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0050] (3) Add 400 mL of water, 12 g of ferric chloride, and 30 mL of aqueous solution containing 9.6 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 160 °C for 24 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0051] Comparative Example 4
[0052] (1) Add 300 mL of water, 20 g of ZSM-5 molecular sieve and 1 g of 3,4-dihydroxyphenylacetic acid to a flask, stir and modify at 30 °C for 2 h, filter, wash with water and dry to obtain molecular sieve support.
[0053] (2) Add 400 mL of water, 20 g of molecular sieve support and 0.8 g of nano ZrO2 to the flask, stir and load at 30 °C for 2 h, filter and dry to obtain molecular sieve loaded ZrO2.
[0054] (3) Add 400 mL of water, 12 g of ferric chloride, and 30 mL of aqueous solution containing 9.6 g of sodium hydroxide to a hydrothermal reactor. Stir and add 30 g of molecular sieve-supported ZrO2. React at 160 °C for 24 h. After filtration, wash with water and dry to obtain the supported ZrO2-Fe2O3 photocatalyst.
[0055] Add 0.1g of methylene blue to deionized water and bring the volume to 1000mL. Transfer the solution to a beaker, add 2g of supported ZrO2-Fe2O3 photocatalyst, and irradiate under a 600W xenon lamp for 2h. Measure the absorbance and concentration of methylene blue in the solution using a UV-Vis spectrophotometer, and calculate the degradation rate Q: Q = (C0 - C) / C0 × 100%. C0 is the concentration of methylene blue in the solution before irradiation, and C is the concentration of methylene blue in the solution after irradiation.
[0056] Add 0.1 g of Rhodamine B to deionized water and bring the volume to 1000 mL. Transfer the solution to a beaker, add 2 g of supported ZrO2-Fe2O3 photocatalyst, and irradiate under a 600 W xenon lamp for 3 h. Measure the absorbance and concentration of Rhodamine B in the solution using a UV-Vis spectrophotometer and calculate the degradation rate Q: Q = (C0 - C) / C0 × 100%. C0 is the concentration of Rhodamine B in the solution before irradiation, and C is the concentration of Rhodamine B in the solution after irradiation.
[0057] Add 0.1 g of tetracycline hydrochloride to deionized water and bring the volume to 1000 mL. Transfer the solution to a beaker, add 3 g of supported ZrO2-Fe2O3 photocatalyst, and irradiate under a 600 W xenon lamp for 4 h. Measure the absorbance and concentration of tetracycline hydrochloride in the solution using a UV-Vis spectrophotometer, and calculate the degradation rate Q: Q = (C0 - C) / C0 × 100%. C0 is the concentration of tetracycline hydrochloride in the solution before irradiation, and C is the concentration of tetracycline hydrochloride in the solution after irradiation.
[0058] Table 1 Photocatalytic Degradation Tests
[0059] ;
[0060] After testing, compared with Comparative Examples 1-4, the ZSM-5 molecular sieve-supported ZrO2-Fe2O3 photocatalysts of Examples 1-4 exhibited higher photocatalytic degradation performance for methylene blue, rhodamine B, and tetracycline hydrochloride. This is mainly because after the molecular sieve was modified with a bis(3-hydroxytyramine) modifier, a large number of catechol structures and carboxyl groups were introduced onto the surface. The catechol forms a coordination interaction with the ZrO2 surface, allowing the nano-ZrO2 to be uniformly loaded onto the molecular sieve surface. At the same time, the large number of carboxyl groups interact with the Fe2O3 surface. 3+ Forming a complex, Fe 3+ After being adsorbed onto the surface of the molecular sieve and undergoing a hydrothermal high-temperature reaction, the generated nano-Fe2O3 is uniformly distributed within the molecular sieve matrix. The nano-ZrO2 and Fe2O3 are uniformly dispersed, not prone to aggregation, and have more photocatalytic active sites. The two form an interfacial coupling heterojunction, which can promote the separation of photogenerated electrons from ZrO2 and Fe2O3, reduce the recombination of photogenerated electrons and holes, and generate a large number of photogenerated electrons and free radicals, etc., which play a good role in the redox degradation of methylene blue, rhodamine B, and tetracycline hydrochloride. At the same time, the molecular sieve has a large specific surface area, and the introduced carboxyl groups have electrostatic interactions with the cationic groups of methylene blue and rhodamine B. The phenolic hydroxyl groups introduced by the molecular sieve form hydrogen bonds with tetracycline hydrochloride containing phenolic hydroxyl groups, which has a higher affinity. This promotes the adsorption of methylene blue, rhodamine B, and tetracycline hydrochloride onto the surface of the catalyst molecular sieve, which can accelerate their catalytic degradation and thus have a higher degradation rate.
[0061] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a ZrO2-Fe2O3 photocatalyst support, characterized by, The preparation method includes: S1. Add water, molecular sieve, and bis(3-hydroxytyramine) modifier to the flask, stir to modify, filter, wash, and dry to obtain molecular sieve carrier. The structural formula of the bis(3-hydroxytyramine) modifier is: or ； S2. Add water, molecular sieve support, and nano ZrO2 to the flask, stir to load, filter and dry to obtain molecular sieve loaded ZrO2. S3. Add water, iron salt, and sodium hydroxide aqueous solution to the hydrothermal reactor, stir and add molecular sieve-supported ZrO2, carry out the reaction, filter, wash and dry to obtain supported ZrO2-Fe2O3 photocatalyst. The ratio of molecular sieve to bis(3-hydroxytyramine) modifier in S1 is 100g:(5-20)g; The modification in S1 is carried out at a temperature of 20-60℃ for 2-5 hours. The preparation method of the bis(3-hydroxytyramine) modifier is as follows: nitrogen gas is introduced into a flask, N,N-dimethylformamide, acid anhydride monomer, dopamine hydrochloride, and triethylamine are added, heated to 70-75℃, and stirred for 18-24 hours. After filtration, the filtrate is concentrated under reduced pressure, dissolved in ethanol, and then precipitated with chloroform. After filtration and drying, the precipitate is obtained as the bis(3-hydroxytyramine) modifier. The acid anhydride monomer is ethylenediaminetetraacetic acid dianhydride or diethylenetriaminepentaacetic acid dianhydride. The molecular sieve is ZSM-5 molecular sieve.
2. The method for preparing the supported ZrO2-Fe2O3 photocatalyst according to claim 1, characterized in that, The ratio of molecular sieve support and nano ZrO2 in S2 is 100g:(4-15)g.
3. The method for preparing the supported ZrO2-Fe2O3 photocatalyst according to claim 1, characterized in that, The temperature during the loading of the stirring in S2 is 20-40℃, and the time is 2-3h.
4. The method for preparing the supported ZrO2-Fe2O3 photocatalyst according to claim 1, characterized in that, The ratio of iron salt, sodium hydroxide, and molecular sieve-loaded ZrO2 in S3 is (12-40)g:(6-32)g:100g.
5. The method for preparing the supported ZrO2-Fe2O3 photocatalyst according to claim 1, characterized in that, The iron salt is ferric chloride or ferric nitrate.
6. The method for preparing the supported ZrO2-Fe2O3 photocatalyst according to claim 1, characterized in that, The reaction temperature in S3 is 140-180℃, and the reaction time is 18-24h.
7. A supported ZrO2-Fe2O3 photocatalyst obtained by the preparation method according to any one of claims 1-6.