CN107837816B - Fe2O3/g-C3N4Composite system, preparation method and application - Google Patents
Fe2O3/g-C3N4Composite system, preparation method and application Download PDFInfo
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- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 title claims abstract description 57
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 239000002131 composite material Substances 0.000 claims abstract description 52
- 239000000243 solution Substances 0.000 claims abstract description 46
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims abstract description 40
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 33
- 238000001035 drying Methods 0.000 claims abstract description 26
- 239000011941 photocatalyst Substances 0.000 claims abstract description 19
- 239000007787 solid Substances 0.000 claims abstract description 18
- 239000000725 suspension Substances 0.000 claims abstract description 18
- 238000005406 washing Methods 0.000 claims abstract description 17
- 229960004989 tetracycline hydrochloride Drugs 0.000 claims abstract description 16
- 238000001354 calcination Methods 0.000 claims abstract description 15
- XMEVHPAGJVLHIG-FMZCEJRJSA-N chembl454950 Chemical compound [Cl-].C1=CC=C2[C@](O)(C)[C@H]3C[C@H]4[C@H]([NH+](C)C)C(O)=C(C(N)=O)C(=O)[C@@]4(O)C(O)=C3C(=O)C2=C1O XMEVHPAGJVLHIG-FMZCEJRJSA-N 0.000 claims abstract description 14
- ZSIQJIWKELUFRJ-UHFFFAOYSA-N azepane Chemical compound C1CCCNCC1 ZSIQJIWKELUFRJ-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000011259 mixed solution Substances 0.000 claims abstract description 13
- 238000005303 weighing Methods 0.000 claims abstract description 12
- 238000003760 magnetic stirring Methods 0.000 claims abstract description 11
- 238000001132 ultrasonic dispersion Methods 0.000 claims abstract description 11
- 238000006243 chemical reaction Methods 0.000 claims abstract description 10
- 238000001816 cooling Methods 0.000 claims abstract description 9
- 239000003344 environmental pollutant Substances 0.000 claims abstract description 9
- 239000007788 liquid Substances 0.000 claims abstract description 9
- 231100000719 pollutant Toxicity 0.000 claims abstract description 9
- 229910021578 Iron(III) chloride Inorganic materials 0.000 claims abstract description 6
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims abstract description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 19
- 238000000227 grinding Methods 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 12
- 238000003756 stirring Methods 0.000 claims description 12
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 8
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 8
- 239000004202 carbamide Substances 0.000 claims description 8
- 239000012153 distilled water Substances 0.000 claims description 8
- 238000001914 filtration Methods 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 8
- 229910017604 nitric acid Inorganic materials 0.000 claims description 8
- 238000002791 soaking Methods 0.000 claims description 8
- WSSMOXHYUFMBLS-UHFFFAOYSA-L iron dichloride tetrahydrate Chemical compound O.O.O.O.[Cl-].[Cl-].[Fe+2] WSSMOXHYUFMBLS-UHFFFAOYSA-L 0.000 claims description 7
- 238000011068 loading method Methods 0.000 claims description 7
- -1 polyethylene Polymers 0.000 claims description 6
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 5
- 229920003171 Poly (ethylene oxide) Polymers 0.000 claims description 2
- 239000004698 Polyethylene Substances 0.000 claims description 2
- 239000004743 Polypropylene Substances 0.000 claims description 2
- 230000000593 degrading effect Effects 0.000 claims description 2
- 229920000573 polyethylene Polymers 0.000 claims description 2
- 229920001155 polypropylene Polymers 0.000 claims description 2
- 229920000428 triblock copolymer Polymers 0.000 claims description 2
- 238000006555 catalytic reaction Methods 0.000 claims 1
- 230000015556 catabolic process Effects 0.000 abstract description 10
- 238000006731 degradation reaction Methods 0.000 abstract description 10
- 230000003197 catalytic effect Effects 0.000 abstract description 5
- 230000015572 biosynthetic process Effects 0.000 abstract description 3
- 238000003786 synthesis reaction Methods 0.000 abstract description 3
- 239000000203 mixture Substances 0.000 description 24
- 230000001699 photocatalysis Effects 0.000 description 13
- 239000002077 nanosphere Substances 0.000 description 7
- 238000004729 solvothermal method Methods 0.000 description 7
- 239000008367 deionised water Substances 0.000 description 6
- 229910021641 deionized water Inorganic materials 0.000 description 6
- 235000019441 ethanol Nutrition 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- 230000001276 controlling effect Effects 0.000 description 3
- 238000004090 dissolution Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000002135 nanosheet Substances 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 230000002194 synthesizing effect Effects 0.000 description 3
- NQTSTBMCCAVWOS-UHFFFAOYSA-N 1-dimethoxyphosphoryl-3-phenoxypropan-2-one Chemical compound COP(=O)(OC)CC(=O)COC1=CC=CC=C1 NQTSTBMCCAVWOS-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 229960002089 ferrous chloride Drugs 0.000 description 2
- 238000000445 field-emission scanning electron microscopy Methods 0.000 description 2
- 238000002173 high-resolution transmission electron microscopy Methods 0.000 description 2
- 231100000252 nontoxic Toxicity 0.000 description 2
- 230000003000 nontoxic effect Effects 0.000 description 2
- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 description 2
- 239000002957 persistent organic pollutant Substances 0.000 description 2
- 238000013033 photocatalytic degradation reaction Methods 0.000 description 2
- 230000006798 recombination Effects 0.000 description 2
- 238000005215 recombination Methods 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 238000000101 transmission high energy electron diffraction Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000003917 TEM image Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000002159 adsorption--desorption isotherm Methods 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000010923 batch production Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000000724 energy-dispersive X-ray spectrum Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 238000000696 nitrogen adsorption--desorption isotherm Methods 0.000 description 1
- 229910052755 nonmetal Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000007146 photocatalysis Methods 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000000527 sonication Methods 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000002604 ultrasonography Methods 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/24—Nitrogen compounds
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D3/00—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances
- A62D3/10—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by subjecting to electric or wave energy or particle or ionizing radiation
- A62D3/17—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by subjecting to electric or wave energy or particle or ionizing radiation to electromagnetic radiation, e.g. emitted by a laser
-
- B01J35/39—
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
- A62D2101/20—Organic substances
- A62D2101/26—Organic substances containing nitrogen or phosphorus
Abstract
The invention belongs to the technical field of photocatalyst synthesis, and particularly relates to Fe2O3/g‑C3N4The composite system, the preparation method and the application can be used for visible light catalytic degradation of tetracycline hydrochloride pollutants. P123 and hexamethyleneimine were accurately weighed, dissolved in a mixed solution of absolute ethanol and ethylene glycol, and stirred to obtain a solution A. Accurately weighing ferric chloride tetrahydrate, and adding the ferric chloride to the solution A to be ultrasonically dissolved to form a solution B. Adding mesoporous g-C into the solution B3N4A suspension C was formed. And carrying out ultrasonic dispersion and magnetic stirring on the suspension C to obtain a turbid liquid D. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃. And after naturally cooling to room temperature, centrifuging, washing and drying to obtain solid F. And (4) putting the solid F into a crucible, and putting the crucible into a muffle furnace for calcining to obtain a sample.
Description
Technical Field
The invention belongs to the technical field of photocatalyst synthesis, and provides a simple and rapid solvothermal method for synthesizing mesoporous Fe in one step2O3Nanosphere-modified g-C3N4Mesoporous 'Z-Scheme' type Fe2O3/g-C3N4The composite system can be used for visible light catalytic degradation of tetracycline hydrochloride pollutants.
Background
With the increasing global energy crisis and the environmental pollution problem, the development and utilization of clean renewable energy sources are imperative. Solar energy is one of the cleanest, the most realistic and the most promising renewable energy sources in the world at present, and is suitable for large-scale development and utilization. The photocatalysis technology has the characteristics of energy conservation, high efficiency, environmental protection and the like, and is an ideal new method for treating environmental pollution by utilizing clean solar energy. However, designing and preparing photocatalytic materials with high photocatalytic performance is still a great challenge for researchers.
In recent years, conductive polymeric carbon nitride materials have attracted much attention as a new target for modifying semiconductor materials because of their excellent optical properties and surface adsorption characteristics. Graphite phase carbon nitride (g-C for short)3N4) The photocatalyst is a unique nonmetal semiconductor photocatalytic material, has the advantages of narrow forbidden band width (2.7eV), capability of responding to visible light, acid resistance, alkali resistance, photo-corrosion resistance, environmental protection and the like, and is one of research hotspots in the field of photocatalytic degradation of organic pollutants. However, g-C3N4Still has some defects, such as low specific surface area, high recombination rate of photo-generated electron-hole pairs, and the like, thereby leading to low photocatalytic performance. The research finds that the g-C is utilized3N4The excellent adsorption performance and the synergistic effect with different energy levels of metal oxide can effectively realize the high-efficiency separation of electron-hole pairs and greatly improve the photocatalytic activity.
Iron oxide is non-toxic, inexpensive, abundant, and exhibits a relatively narrow band gap, and is capable of responding to a wide range of visible light. However, the single iron oxide has low photocatalytic activity due to high recombination rate of photogenerated carriers. Thus, with Fe2O3Is a composite structural unit with g-C3N4Construction of a "Z-Scheme" type composite system by Fe2O3In g-C3N4The nano-scale morphology and structure on the surface are regulated and controlled to improve the composite mode, so that the photocatalytic performance can be greatly improved, the nano-scale morphology and structure can be used for removing organic pollutants in water, and a new way is opened up for constructing a novel composite visible light catalytic material.
In this work, mesoporous Fe was used2O3Nanosphere pair g-C3N4Surface modification is carried out, and mesoporous Z-Scheme type Fe is constructed in one step by a simple and rapid solvothermal method2O3/g-C3N4And (3) a composite system. With pure g-C3N4In contrast, the best mesoporous "Z-Scheme" type Fe2O3/g-C3N4The photocatalytic activity of the composite system reaches 73.78 percent of the degradation rate of tetracycline hydrochloride within 120min, and the degradation rate is pure g-C3N42.63 times of (28.08%). Mesoporous Fe2O3Nanosphere pair g-C3N4The surface modification effect of the tetracycline hydrochloride compound has the advantages that the light collection capability and the carrier separation efficiency of the tetracycline hydrochloride compound are obviously improved, the specific surface area and the surface active sites are increased, and finally, the tetracycline hydrochloride pollutant degradation efficiency is greatly improved. Up to now, no one-step solvothermal method for synthesizing mesoporous Fe has been found2O3Nanosphere-modified g-C3N4Of the "Z-Scheme" type Fe2O3/g-C3N4And (3) a composite system.
Disclosure of Invention
The invention belongs to the technical field of nano material synthesis, and provides a simple and rapid solvothermal method for synthesizing mesoporous Fe in one step2O3Nanosphere-modified g-C3N4Mesoporous 'Z-Scheme' type Fe2O3/g-C3N4The composite system can be used for visible light catalytic degradation of tetracycline hydrochloride pollutants.
The preparation method of the invention is characterized by comprising the following steps:
preparation of g-C3N4Photocatalyst and process for producing the same
1. Weighing urea, drying in an oven at 80 deg.C for 24h, grinding and loading into a crucible, adding a lid, and heating in a muffle furnace at 2 deg.C for 2 min-1The temperature of the mixture is increased from room temperature to 550 ℃, and the mixture is calcined for 4 hours.
2. Taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24 hr, filtering, washing with distilled water for 7-8 times to neutrality, and drying in 80 deg.C oven for 24 hr.
3. Taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
Secondly, preparing mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Composite system
1. Accurately weighing a polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer (P123) and hexamethyleneimine, dissolving in a mixed solution of absolute ethanol and ethylene glycol, and stirring to obtain a solution A.
2. Accurately weighing ferric chloride tetrahydrate, and adding the ferric chloride to the solution A to be ultrasonically dissolved to form a solution B.
3. Adding mesoporous g-C into the solution B3N4A suspension C was formed.
4. And carrying out ultrasonic dispersion and magnetic stirring on the suspension C to obtain a turbid liquid D.
5. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃.
6. And after naturally cooling to room temperature, centrifuging, washing and drying to obtain solid F.
7. And (4) putting the solid F into a crucible, and putting the crucible into a muffle furnace for calcining to obtain a sample.
The mass volume ratio of the P123 to the hexamethyleneimine to the mixed solution of the absolute ethyl alcohol and the glycol is 0.2 g: 0.1 g: 29.5ml, wherein in the mixed solution of the absolute ethyl alcohol and the glycol, the volume ratio of the absolute ethyl alcohol to the glycol is 16.5: 13; g-C3N4And the mass ratio of P123 to hexamethyleneimine is 3: 2: 1.
wherein the amount of iron dichloride tetrahydrate is in terms of Fe2O3And g-C3N40.003: 0.3 to 0.045: 0.3 weight of mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Fe in composite system2O3For g-C3N4Are in each case 1 to 15 wt.%, preferably 5 wt.%.
In the step (1), the stirring time is 30 min.
In the step (4), the ultrasonic dispersion time is 30min, and the magnetic stirring time is 48 h.
The drying temperature in the step (6) is 80 ℃.
In the step (7), the calcining temperature is 350 ℃, and the calcining time is 2 h.
In the inventionUsing X-ray diffraction (XRD), Transmission Electron Microscope (TEM), N2Adsorption-desorption isotherm and BJH pore size distribution and other means for mesoporous 'Z-Scheme' type Fe2O3/g-C3N4And (5) characterizing the composite system. As shown in FIG. 1, by Fe2O3After surface modification, g-C3N4The XRD diffraction peak of (A) is hardly changed, probably due to mesoporous Fe2O3Low content of nanospheres. FIG. 2(a, b) shows pure g-C3N4And mesoporous "Z-Scheme" type Fe2O3/g-C3N4FESEM photograph and EDS energy spectrum (inset) of the composite system, and g-C can be seen from the figure3N4In a lamellar structure, Fe2O3The nanospheres are uniformly dispersed in g-C3N4And (3) the surface of the nanosheet. Meanwhile, FIG. 2(C) is pure g-C3N4The TEM photograph of (A) shows that g-C was clearly observed3N4The nanosheet form of (a). While FIG. 2(d, e) shows mesoporous "Z-Scheme" type Fe2O3/g-C3N4In the TEM photograph of (1), Fe was observed2O3The nanosphere is uniformly modified in g-C3N4Nanosheet surface, about 140nm in diameter, and Fe2O3The nanospheres exhibit a mesoporous structural characteristic consisting of nanodots. FIG. 2(f) shows mesoporous "Z-Scheme" type Fe2O3/g-C3N4HRTEM and SAED photographs (inset) of (1), the lattice spacing of which is 0.252nm, corresponding to Fe2O3And the nano dots are in a single crystal state. In addition, N in FIG. 3(a, b)2The absorption and desorption curve and the pore size distribution further prove that the sample is of a mesoporous structure, and the pore size is about 35 nm. FIG. 4(a, b) shows that the obtained mesoporous "Z-Scheme" type Fe2O3/g-C3N4The composite system obviously enhances the photocatalytic performance of degrading tetracycline hydrochloride pollutants, and has higher stability and reusability.
In the invention, the mesoporous 'Z-Scheme' type Fe is constructed by accurately controlling the reaction conditions and the amount of reactants2O3/g-C3N4And (3) a composite system. Mesoporous Fe2O3Nanosphere pair g-C3N4The modification effect of (2) obviously improves the separation efficiency and light absorption capacity of carriers, and increases the specific surface area and surface active sites, which is the main reason for improving the photocatalytic activity. The invention is different from the prior art and is characterized in that the mesoporous Fe is synthesized by adopting the simple one-step solvothermal method2O3Nanosphere-modified g-C3N4Mesoporous 'Z-Scheme' type Fe2O3/g-C3N4A composite system, and the mesoporous 'Z-Scheme' type Fe2O3/g-C3N4The composite system solves the problem that some photocatalysts have low degradation efficiency on tetracycline hydrochloride pollutants under visible light.
The main purposes of the invention are as follows: providing a typical example for constructing a Z-Scheme composite system by regulating and controlling the surface microstructure of the heterojunction through a simple method; second, mesoporous Fe2O3Nanosphere-modified g-C3N4Mesoporous 'Z-Scheme' type Fe2O3/g-C3N4The composite system can be used for photocatalytic degradation of tetracycline hydrochloride pollutants under visible light.
Advantageous effects
Simple and rapid one-step solvothermal method is utilized to construct mesoporous Fe2O3Nanosphere-modified g-C3N4Mesoporous 'Z-Scheme' type Fe2O3/g-C3N4A composite system which degrades tetracycline hydrochloride under visible light and shows excellent photocatalytic activity; the method has the advantages of simple process, convenient operation and short reaction time, thereby reducing energy consumption and production cost, being convenient for batch production, being nontoxic and harmless and meeting the environment-friendly requirement.
Drawings
FIGS. 1 g-C3N4And mesoporous "Z-Scheme" type Fe2O3/g-C3N4XRD spectrum of the complex system.
FIG. 2 g-C3N4And mesoporous "Z-Scheme" type Fe2O3/g-C3N4FESEM pictures (a, b) and EDS spectra (b inset), g-C of the composite system3N4(c) And mesoporous "Z-Scheme" type Fe2O3/g-C3N4TEM micrograph of the composite System (d, e) and mesoporous "Z-Scheme" type Fe2O3/g-C3N4HRTEM (f) and SAED (f inset) of the composite system.
FIGS. 3 g-C3N4And mesoporous "Z-Scheme" type Fe2O3/g-C3N4N of a composite system2Adsorption-desorption isotherms (a) and pore size distribution (b).
FIG. 4 shows the kinetics curve (a) of tetracycline hydrochloride degradation of the sample under visible light and the degradation rate (b) after five cycles.
Detailed Description
Example 1: mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Preparation of the composite System
Preparation of g-C3N4Photocatalyst and process for producing the same
1. Weighing urea, drying in an oven at 80 deg.C for 24h, grinding and loading into a crucible, adding a lid, and heating in a muffle furnace at 2 deg.C for 2 min-1The temperature of the mixture is increased from room temperature to 550 ℃, and the mixture is calcined for 4 hours.
2. Taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24 hr, filtering, washing with distilled water for 7-8 times to neutrality, and drying in 80 deg.C oven for 24 hr.
3. Taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
Secondly, preparing mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Composite system
1. 0.2g P123 and 0.1g of hexamethyleneimine were accurately weighed, dissolved in a mixed solution of 16.5ml of anhydrous ethanol and 13ml of ethylene glycol, and stirred for 30min to obtain a solution A.
2. 0.0077g of iron dichloride tetrahydrate is accurately weighed and added into the solution A to be ultrasonically dissolved to form a solution B.
3. 0.3g of g-C was added to the solution B3N4A suspension C was formed.
4. And (4) carrying out ultrasonic dispersion on the suspension C for 30min, and then carrying out magnetic stirring for 48h to obtain a turbid liquid D.
5. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃.
6. After naturally cooling to room temperature, centrifugally washing the mixture for three times by using deionized water and ethanol, and drying the mixture in an oven at the temperature of 80 ℃ to obtain solid F.
7. And (3) putting the solid F into a crucible, and putting the crucible into a muffle furnace at 350 ℃ to calcine for 2h to obtain a sample.
Example 2: mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Preparation of the composite System
Preparation of g-C3N4Photocatalyst and process for producing the same
1. Weighing urea, drying in an oven at 80 deg.C for 24h, grinding and loading into a crucible, adding a lid, and heating in a muffle furnace at 2 deg.C for 2 min-1The temperature of the mixture is increased from room temperature to 550 ℃, and the mixture is calcined for 4 hours.
2. Taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24 hr, filtering, washing with distilled water for 7-8 times to neutrality, and drying in 80 deg.C oven for 24 hr.
3. Taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
Secondly, preparing mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Composite system
1. 0.2g of P123 and 0.1g of hexamethyleneimine were accurately weighed, dissolved in a mixed solution of 16.5ml of absolute ethanol and 13ml of ethylene glycol, and stirred for 30 minutes to obtain a solution A.
2. 0.0231g of tetrahydrate ferrous chloride is accurately weighed and added into the solution A to be dissolved by ultrasound to form a solution B.
3. 0.3g of g-C was added to the solution B3N4A suspension C was formed.
4. And (4) carrying out ultrasonic dispersion on the suspension C for 30min, and then carrying out magnetic stirring for 48h to obtain a turbid liquid D.
5. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃.
6. After naturally cooling to room temperature, centrifugally washing the mixture for three times by using deionized water and ethanol, and drying the mixture in an oven at the temperature of 80 ℃ to obtain solid F.
7. And (3) putting the solid F into a crucible, and putting the crucible into a muffle furnace at 350 ℃ to calcine for 2h to obtain a sample.
Example 3: mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Preparation of the composite System
Preparation of g-C3N4Photocatalyst and process for producing the same
1. Weighing urea, drying in an oven at 80 deg.C for 24h, grinding and loading into a crucible, adding a lid, and heating in a muffle furnace at 2 deg.C for 2 min-1The temperature of the mixture is increased from room temperature to 550 ℃, and the mixture is calcined for 4 hours.
2. Taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24 hr, filtering, washing with distilled water for 7-8 times to neutrality, and drying in 80 deg.C oven for 24 hr.
3. Taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
Secondly, preparing mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Composite system
1. 0.2g of P123 and 0.1g of hexamethyleneimine were accurately weighed, dissolved in a mixed solution of 16.5ml of absolute ethanol and 13ml of ethylene glycol, and stirred for 30 minutes to obtain a solution A.
2. 0.0386g of iron dichloride tetrahydrate were accurately weighed and added to solution A for ultrasonic dissolution to form solution B.
3. 0.3g of g-C was added to the solution B3N4A suspension C was formed.
4. And (4) carrying out ultrasonic dispersion on the suspension C for 30min, and then carrying out magnetic stirring for 48h to obtain a turbid liquid D.
5. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃.
6. After naturally cooling to room temperature, centrifugally washing the mixture for three times by using deionized water and ethanol, and drying the mixture in an oven at the temperature of 80 ℃ to obtain solid F.
7. And (3) putting the solid F into a crucible, and putting the crucible into a muffle furnace at 350 ℃ to calcine for 2h to obtain a sample.
Example 4: mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Preparation of the composite System
Preparation of g-C3N4Photocatalyst and process for producing the same
1. Urea was weighed, dried in an oven at 80 ℃ for 24h, ground and loaded into a crucible, covered with a lid, heated in a muffle furnace at a ramp rate of 2 ℃/min from room temperature to 550 ℃ and calcined for 4 h.
2. Taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24 hr, filtering, washing with distilled water for 7-8 times to neutrality, and drying in 80 deg.C oven for 24 hr.
3. Taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
Secondly, preparing mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Composite system
1. 0.2g of P123 and 0.1g of hexamethyleneimine were accurately weighed, dissolved in a mixed solution of 16.5ml of absolute ethanol and 13ml of ethylene glycol, and stirred for 30 minutes to obtain a solution A.
2. 0.0540g of iron dichloride tetrahydrate is accurately weighed and added to solution A for ultrasonic dissolution to form solution B.
3. 0.3g of g-C was added to the solution B3N4A suspension C was formed.
4. And (4) carrying out ultrasonic dispersion on the suspension C for 30min, and then carrying out magnetic stirring for 48h to obtain a turbid liquid D.
5. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃.
6. After naturally cooling to room temperature, centrifugally washing the mixture for three times by using deionized water and ethanol, and drying the mixture in an oven at the temperature of 80 ℃ to obtain solid F.
7. And (3) putting the solid F into a crucible, and putting the crucible into a muffle furnace at 350 ℃ to calcine for 2h to obtain a sample.
Example 5: mesoporous structure"Z-Scheme" type Fe2O3/g-C3N4Preparation of the composite System
Preparation of g-C3N4Photocatalyst and process for producing the same
1. Weighing urea, drying in an oven at 80 deg.C for 24h, grinding and loading into a crucible, adding a lid, and heating in a muffle furnace at 2 deg.C for 2 min-1The temperature of the mixture is increased from room temperature to 550 ℃, and the mixture is calcined for 4 hours.
2. Taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24 hr, filtering, washing with distilled water for 7-8 times to neutrality, and drying in 80 deg.C oven for 24 hr.
3. Taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
Secondly, preparing mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Composite system
1. 0.2g of P123 and 0.1g of hexamethyleneimine were accurately weighed, dissolved in a mixed solution of 16.5ml of absolute ethanol and 13ml of ethylene glycol, and stirred for 30 minutes to obtain a solution A.
2. 0.0771 g of iron dichloride tetrahydrate was accurately weighed and added to solution A and dissolved by sonication to form solution B.
3. 0.3g of g-C was added to the solution B3N4A suspension C was formed.
4. And (4) carrying out ultrasonic dispersion on the suspension C for 30min, and then carrying out magnetic stirring for 48h to obtain a turbid liquid D.
5. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃.
6. After naturally cooling to room temperature, centrifugally washing the mixture for three times by using deionized water and ethanol, and drying the mixture in an oven at the temperature of 80 ℃ to obtain solid F.
7. And (3) putting the solid F into a crucible, and putting the crucible into a muffle furnace at 350 ℃ to calcine for 2h to obtain a sample.
Example 6: mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Preparation of the composite System
Preparation of g-C3N4Photocatalyst and process for producing the same
1. Weighing urea, drying in an oven at 80 deg.C for 24h, grinding and loading into a crucible, adding a lid, and heating in a muffle furnace at 2 deg.C for 2 min-1The temperature of the mixture is increased from room temperature to 550 ℃, and the mixture is calcined for 4 hours.
2. Taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24 hr, filtering, washing with distilled water for 7-8 times to neutrality, and drying in 80 deg.C oven for 24 hr.
3. Taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
Secondly, preparing mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Composite system
1. 0.2g of P123 and 0.1g of hexamethyleneimine were accurately weighed, dissolved in a mixed solution of 16.5ml of absolute ethanol and 13ml of ethylene glycol, and stirred for 30 minutes to obtain a solution A.
2. 0.1157g of iron dichloride tetrahydrate were accurately weighed and added to solution A for ultrasonic dissolution to form solution B.
3. 0.3g of g-C was added to the solution B3N4A suspension C was formed.
4. And (4) carrying out ultrasonic dispersion on the suspension C for 30min, and then carrying out magnetic stirring for 48h to obtain a turbid liquid D.
5. Transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃.
6. After naturally cooling to room temperature, centrifugally washing the mixture for three times by using deionized water and ethanol, and drying the mixture in an oven at the temperature of 80 ℃ to obtain solid F.
7. And (3) putting the solid F into a crucible, and putting the crucible into a muffle furnace at 350 ℃ to calcine for 2h to obtain a sample.
The mesoporous Fe is prepared by regulating and controlling the mass of the added tetrahydrate ferrous chloride through a one-step solvothermal method2O3Nanosphere-modified g-C3N4"Z-Scheme" type mesoporous Fe2O3/g-C3N4A compound system, which respectively considers that 50mg of each sample can react with tetracycline hydrochloride solution (10mg L) under visible light-1) The result shows that the unique mesoporous 'Z-Scheme' type Fe2O3/g-C3N4The composite system significantly enhances photocatalytic activity. Furthermore, 5% by weight of mesoporous "Z-Scheme" type Fe2O3/g-C3N4The composite system has the best catalytic performance, and the degradation rate of tetracycline hydrochloride reaches 73.78% after 120min of visible light irradiation, which indicates that the obtained mesoporous 'Z-Scheme' type Fe2O3/g-C3N4The composite system can be applied to the treatment of tetracycline hydrochloride pollutants.
Claims (9)
1.Fe2O3/g-C3N4A composite system of mesoporous Fe2O3Nanosphere-modified g-C3N4Mesoporous 'Z-Scheme' type Fe2O3/g-C3N4The composite system is characterized by being prepared by the following method:
(1) accurately weighing a polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer (P123) and hexamethyleneimine, dissolving in a mixed solution of absolute ethyl alcohol and ethylene glycol, and stirring to obtain a solution A;
(2) accurately weighing ferric chloride tetrahydrate, and adding the ferric chloride tetrahydrate into the solution A to be ultrasonically dissolved to form a solution B;
(3) adding mesoporous g-C into the solution B3N4Forming a suspension C;
(4) carrying out ultrasonic dispersion and magnetic stirring on the suspension C to obtain a turbid liquid D;
(5) transferring the turbid solution D into a reaction kettle, and reacting for 15h in an oven at 200 ℃;
(6) after naturally cooling to room temperature, centrifuging, washing and drying to obtain solid F;
(7) putting the solid F into a crucible, and putting the crucible into a muffle furnace for calcining to obtain a sample;
the mesoporous g-C3N4The preparation method comprises the following steps:
weighing urea, drying in an oven at 80 deg.C for 24h, grinding and loading into a crucible, adding a lid, and heating in a muffle furnace at 2 deg.C for 2 min-1Heating rate of from room temperature toCalcining for 4h at 550 ℃;
taken out and then used for 1mol L-1Soaking in nitric acid, stirring for 24h, filtering, washing with distilled water for 7-8 times to neutrality, and drying in an oven at 80 deg.C for 24 h;
taking out a sample, grinding, placing in a crucible, calcining in a muffle furnace at 500 ℃ for 4h without covering to obtain mesoporous g-C3N4A photocatalyst.
2. Fe as claimed in claim 12O3/g-C3N4The composite system is characterized in that the mass volume ratio of the P123, the hexamethyleneimine to the mixed solution of the absolute ethyl alcohol and the ethylene glycol is 0.2 g: 0.1 g: 29.5ml, wherein in the mixed solution of the absolute ethyl alcohol and the glycol, the volume ratio of the absolute ethyl alcohol to the glycol is 16.5: 13; g-C3N4And the mass ratio of P123 to hexamethyleneimine is 3: 2: 1.
3. fe as claimed in claim 12O3/g-C3N4Composite system, characterized in that the amount of iron dichloride tetrahydrate is in accordance with Fe2O3And g-C3N40.003: 0.3 to 0.045: 0.3 weight of mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Fe in composite system2O3For g-C3N4Is 1 wt% to 15 wt%.
4. Fe as claimed in claim 32O3/g-C3N4A composite system characterized by mesoporous 'Z-Scheme' type Fe2O3/g-C3N4Fe in composite system2O3For g-C3N4Is 5 wt%.
5. Fe as claimed in claim 12O3/g-C3N4The composite system is characterized in that in the step (1), the stirring time is 30 min.
6. Fe as claimed in claim 12O3/g-C3N4The composite system is characterized in that in the step (4), the ultrasonic dispersion time is 30min, and the magnetic stirring time is 48 h.
7. Fe as claimed in claim 12O3/g-C3N4The composite system is characterized in that the drying temperature in the step (6) is 80 ℃.
8. Fe as claimed in claim 12O3/g-C3N4The composite system is characterized in that the calcination temperature in the step (7) is 350 ℃, and the calcination time is 2 hours.
9. Fe as claimed in any one of claims 1 to 82O3/g-C3N4The application of the composite system is used for degrading tetracycline hydrochloride pollutants by visible light catalysis.
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Denomination of invention: Fe2O3/g-C3N4composite system, preparation method and application Effective date of registration: 20230816 Granted publication date: 20200124 Pledgee: Industrial and Commercial Bank of China Limited Yangzhong sub branch Pledgor: DAQO GROUP Co.,Ltd. Registration number: Y2023980052153 |