CN113145170A - Preparation method of visible light full-absorption saturated phosphomolybdate composite material with Keggin structure - Google Patents
Preparation method of visible light full-absorption saturated phosphomolybdate composite material with Keggin structure Download PDFInfo
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- CN113145170A CN113145170A CN202011639610.8A CN202011639610A CN113145170A CN 113145170 A CN113145170 A CN 113145170A CN 202011639610 A CN202011639610 A CN 202011639610A CN 113145170 A CN113145170 A CN 113145170A
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- 239000002131 composite material Substances 0.000 title claims abstract description 49
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- 238000002360 preparation method Methods 0.000 title claims abstract description 30
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- DHRLEVQXOMLTIM-UHFFFAOYSA-N phosphoric acid;trioxomolybdenum Chemical compound O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.O=[Mo](=O)=O.OP(O)(O)=O DHRLEVQXOMLTIM-UHFFFAOYSA-N 0.000 claims description 5
- 239000001509 sodium citrate Substances 0.000 claims description 5
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 claims description 5
- 239000011684 sodium molybdate Substances 0.000 claims description 5
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- TVXXNOYZHKPKGW-UHFFFAOYSA-N sodium molybdate (anhydrous) Chemical compound [Na+].[Na+].[O-][Mo]([O-])(=O)=O TVXXNOYZHKPKGW-UHFFFAOYSA-N 0.000 claims description 5
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 4
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- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 8
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- CXKWCBBOMKCUKX-UHFFFAOYSA-M methylene blue Chemical compound [Cl-].C1=CC(N(C)C)=CC2=[S+]C3=CC(N(C)C)=CC=C3N=C21 CXKWCBBOMKCUKX-UHFFFAOYSA-M 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
- B01J27/14—Phosphorus; Compounds thereof
- B01J27/186—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J27/188—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium with chromium, molybdenum, tungsten or polonium
- B01J27/19—Molybdenum
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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
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
- B01J35/39—Photocatalytic properties
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/30—Treatment of water, waste water, or sewage by irradiation
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
- C02F2101/308—Dyes; Colorants; Fluorescent agents
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2305/00—Use of specific compounds during water treatment
- C02F2305/10—Photocatalysts
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
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Abstract
The invention discloses a preparation method of a visible light full-absorption saturated type Keggin structure phosphomolybdate composite material, which is characterized in that nano silver with different sizes and shapes is controllably synthesized by adjusting reaction parameters, and after the nano silver is compounded with heteropoly acid, the saturated type Keggin structure phosphomolybdate composite catalyst shows different absorption ranges in a visible light region, so that the controllable preparation of a novel photocatalyst with full spectrum and strong absorption in the visible light region is realized, and a catalytic experiment shows that the saturated type Keggin structure phosphomolybdate composite catalyst shows excellent catalytic effect on a photodegradation experiment of a simulated pigment.
Description
Technical Field
The invention relates to the technical field of phosphomolybdate composite materials, in particular to a preparation method of a visible light full-absorption saturated phosphomolybdate composite material with a Keggin structure.
Background
With the continuous development of industrialization, environmental pollution has become a serious problem facing and needing to be solved by human beings. Wherein the industrial wastewater in the dye industry, the chemical industry and the like has prominent harm to the environment. The components of the dye wastewater are complex and high in concentration, the organic components of the dye wastewater usually adopt aromatic hydrocarbon and heterocyclic compounds as matrixes, and the dye wastewater has chromogenic groups and high toxicity, and some dye wastewater even contains highly toxic carcinogens. Therefore, the treatment of dye wastewater is urgent, otherwise, the dye wastewater has great harm to the ecological environment and the health of human beings. Rhodamine B (RhB) is an organic dye commonly used in industry, and the structure of the rhodamine B (RhB) contains benzene rings which are high in toxicity and difficult to degrade, and the rhodamine B (RhB) is taken as a target research object and is subjected to decolorization treatment.
The heteropoly acid has been widely used in the field of catalysis due to its many excellent characteristics, such as unique structural adjustability and redox properties. At present, the photocatalyst has related reports on degrading organic dyes. When the heteropoly acid which is researched is used as a photocatalyst, the light absorption is mainly limited in an ultraviolet region and a near visible light region, and the sunlight utilization rate is low. The noble metal nano material has unique optical properties and can controllably adjust the absorption waveband to a visible light region. Therefore, the paper proposes that the heteropoly acid and the noble metal nano material are compounded to prepare the novel heteropoly acid nano composite photocatalyst, so that the response activity to visible light is enhanced, and the photocatalytic efficiency is improved.
The subject group filed in 2017 for a patent of preparation and photocatalytic application of Keggin type saturated phosphomolybdate and a coating material thereof, and the patent discloses a good saturated phosphomolybdate and a coating material thereof which have a very good catalytic degradation effect on wastewater, particularly methylene blue dye wastewater. However, the utilization efficiency of the saturated phosphomolybdate and the coating material thereof prepared by the method on visible light still needs to be improved, and in order to further improve the photocatalytic efficiency of the catalyst, the invention provides a preparation method of a visible light full-absorption saturated type Keggin structure phosphomolybdate composite material.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides a preparation method of a visible light full-absorption saturated phosphomolybdate composite material with a Keggin structure.
The technical scheme of the invention is as follows:
a preparation method of a visible light full-absorption saturated phosphomolybdate composite material with a Keggin structure comprises the following steps:
A. preparing phosphomolybdate with a saturated Keggin structure;
B. preparing a silver nano material;
C. preparing a saturated phosphomolybdate/silver nano composite material with a Keggin structure;
the phosphomolybdate with the saturated Keggin structure is a phosphomolybdic acid precursor and is marked as PMo12。
Preferably, the preparation method of the phosphomolybdic heteropoly acid precursor comprises the following steps: mixing and dissolving sodium molybdate and phosphoric acid with deionized water, then placing the mixture in a water bath for heating at 80-90 ℃ and continuously stirring, dropwise adding hydrochloric acid to adjust the pH value to 2-3 after 25-35min, continuously stirring at constant temperature for 8-15min, then adding cobalt chloride and phenanthroline to fully react for 8-15min, dropwise adding a saturated sodium carbonate solution to adjust the pH value to 6-7, continuously stirring at constant temperature for 25-35min, cooling the mixed solution obtained by the reaction to room temperature, finally transferring the mixed solution to a stainless steel reaction kettle with a polytetrafluoroethylene lining, and heating and reacting for 5-6h at 190 ℃ with 170-; after the reaction is finished, cooling, centrifuging and drying to obtain a phosphomolybdic heteropoly acid precursor which is recorded as PMo12。
Preferably, the preparation method of the silver nano material comprises the following steps: mixing a volume of AgNO3Adding the aqueous solution and the sodium citrate solution into water, stirring uniformly, adding polyvinylpyrrolidone (PVP) solution for mixing, continuously stirring and quickly adding freshly prepared NaBH4Fully stirring the aqueous solution for 3-8min, and placing the mixed solution under a 100W tungsten lamp for irradiation; and after the illumination is finished, washing the sample by using absolute ethyl alcohol and deionized water, and centrifuging for later use.
Preferably, the preparation method of the saturated Keggin phosphomolybdate/silver nanocomposite comprises the following steps: will PMo12After cooling, the upper layer solution is removed and the lower layer mixture is mixed with a volume of silverPerforming nano-compounding, continuously stirring at a certain temperature for 25-35min, transferring the mixed solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, and reacting and heating at the constant temperature of 170-190 ℃ for 5-6 h; after the reaction is finished, cooling the sample to room temperature, centrifuging and drying to obtain the phosphomolybdate/silver nano composite material which is recorded as PMo 12/Ag.
Preferably, in the step B, the irradiation time of the tungsten lamp is adjusted, the silver nano-materials prepared under different conditions are taken and mixed, and then the step C is performed.
Further preferably, the silver nano-materials prepared under different conditions can be silver nano-materials obtained by respectively irradiating the silver nano-materials for 0h, 8h, 12h, 16h and 20h by using a 100W tungsten lamp.
The invention has the advantages that: the invention provides a simple synthesis method, which is characterized in that nano silver with different sizes and appearances is controllably synthesized by adjusting reaction parameters, and after the nano silver is compounded with heteropoly acid, the saturated Keggin phosphomolybdate composite catalyst shows different absorption ranges in a visible light region, so that the controllable preparation of a novel photocatalyst with full spectrum and strong absorption in the visible light region is realized, and a catalytic experiment shows that the novel photocatalyst shows excellent catalytic effect on a photodegradation experiment of a simulated pigment.
Drawings
FIG. 1: color change pattern in silver nano conversion process;
FIG. 2: ultraviolet absorption spectrogram of silver nanoparticles;
FIG. 3: ultraviolet spectrograms of different time periods in the process of generating the silver nano flaky structure;
FIG. 4: scanning electron micrographs at different time periods in the process of generating the silver nano flaky structure;
FIG. 5: an ultraviolet spectrogram corresponding to the silver nanosheet structure;
FIG. 6: scanning an electron microscope image of the silver nanosheet structure;
FIG. 7: PMo12An infrared spectrogram of the precursor;
FIG. 8: PMo12An infrared spectrogram of the Ag sample;
FIG. 9: PMo12Of precursorsXRD spectrogram;
FIG. 10: PMo12XRD spectrogram of Ag sample;
FIG. 11: PMo12Ultraviolet absorption spectrogram of the precursor;
FIG. 12: PMo12Ultraviolet absorption spectrograms of samples before and after Ag compounding;
FIG. 13: PMo12 precursor and PMo12Electron microscope representation of the morphology and structure of Ag; wherein (a) PMo12Scanning an electron microscope image; (b) PMo12A precursor EDS; (c) PMo12Ag scanning electron microscope picture; (d) PMo12EDS of Ag sample; (e-h) PMo12The TEM-EDS element mapping of the/Ag sample corresponds to a P, Mo and Ag element distribution diagram;
FIG. 14: PMo12Comparison graph of decolorization rate before and after Ag compounding;
FIG. 15: PMo12Ag photocatalysis ultraviolet absorption spectrogram;
FIG. 16: PMo12Ag Recycling experiment Ct/C0A graph of changes over time;
FIG. 17: PMo12Ag recycling experiment sample infrared contrast chart;
FIG. 18: PMo12And PMo12The emission spectrum of the Ag sample;
FIG. 19: graph of the effect of different active species on the catalytic effect.
Detailed Description
Example 1
A preparation method of a visible light full-absorption saturated phosphomolybdate composite material with a Keggin structure comprises the following steps:
A. preparing phosphomolybdate with a saturated Keggin structure;
B. preparing a silver nano material;
C. preparing the saturated phosphomolybdate/silver nano composite material with the Keggin structure.
The phosphomolybdate with the saturated Keggin structure is a phosphomolybdic acid precursor and is marked as PMo12。
The preparation method of the phosphomolybdic heteropoly acid precursor comprises the following steps: sodium molybdate 0.4000g (1.65mmol) phosphoric acid 0.1mL, and 30mLMixing and dissolving deionized water, then placing the mixture in a water bath at 85 ℃ for heating and continuously stirring, dropwise adding hydrochloric acid (6mol/L) after 30min to adjust the pH value to 2-3, continuously stirring at constant temperature for 10min, then adding 0.0400g of cobalt chloride and 0.0200g of phenanthroline to fully react for 10min, dropwise adding a saturated sodium carbonate solution to adjust the pH value to 6-7, continuously stirring at constant temperature for 30min, cooling the mixed solution obtained by the reaction to room temperature, finally transferring the mixed solution to a stainless steel reaction kettle with a 15mL volume and a polytetrafluoroethylene lining, and heating and reacting for 5.5h at 180 ℃. After the reaction is finished, cooling, centrifuging and drying to obtain a phosphomolybdic heteropoly acid precursor which is recorded as PMo12。
The preparation method of the silver nano material comprises the following steps: mixing a volume of AgNO3Adding 0.2 mol/L aqueous solution and 0.6mol/L sodium citrate solution into 500mL water, stirring, adding 5mmol/L polyvinylpyrrolidone (PVP) solution, mixing, continuously stirring, and rapidly adding freshly prepared NaBH4The aqueous solution (0.1mol/L) was stirred well for 5min, and the mixed solution was placed under a 100W tungsten lamp for irradiation, and the experiment was performed under a dark condition in order to avoid the influence of other light rays on the experiment. Sampling at regular time in the process of the illumination reaction, and carrying out ultraviolet-visible absorption spectrum test on the sample. And after the illumination is finished, washing the sample by using absolute ethyl alcohol and deionized water, and centrifuging for later use.
Adjusting the irradiation time of different tungsten filament lamps, taking the silver nano materials prepared under different conditions, mixing, washing and centrifuging for later use; the silver nano material prepared under different conditions is PMo prepared by irradiating the silver nano material for 0h, 8h, 12h, 16h and 20h by using a 100W tungsten lamp according to the mass ratio of 1:1:1:1:112。
The preparation method of the saturated phosphomolybdate/silver nano composite material with the Keggin structure comprises the following steps: will PMo12And after cooling, removing the upper solution, compounding the lower mixed solution with a certain volume of silver nano-particles, continuously stirring for 30min at a certain temperature, finally transferring the mixed solution into a stainless steel reaction kettle with a volume of 15mL and a polytetrafluoroethylene lining, and carrying out reaction heating for 5.5h at the constant temperature of 180 ℃. Inverse directionAfter the reaction is finished, cooling the sample to room temperature, centrifuging and drying to obtain the phosphomolybdate/silver nano composite material which is recorded as PMo12/Ag。
Example 2
A preparation method of a visible light full-absorption saturated phosphomolybdate composite material with a Keggin structure comprises the following steps:
A. preparing phosphomolybdate with a saturated Keggin structure;
B. preparing a silver nano material;
C. preparing the saturated phosphomolybdate/silver nano composite material with the Keggin structure.
The phosphomolybdate with the saturated Keggin structure is a phosphomolybdic acid precursor and is marked as PMo12。
The preparation method of the phosphomolybdic heteropoly acid precursor comprises the following steps: 0.4000g (1.65mmol) of sodium molybdate 0.1mL is mixed and dissolved with 30mL of deionized water, then the mixture is placed in a water bath at 85 ℃ for heating and is continuously stirred, hydrochloric acid (6mol/L) is dripped after 25min to adjust the pH value to 2-3, the mixture is continuously stirred at constant temperature for 8min, then 0.0400g of cobalt chloride and 0.0200g of phenanthroline are added to fully react for 15min, saturated sodium carbonate solution is dripped to adjust the pH value to 6-7, the mixture is continuously stirred at constant temperature for 25min, the mixed solution obtained by the reaction is cooled to room temperature, finally the mixed solution is transferred to a stainless steel reaction kettle with a polytetrafluoroethylene lining, and is heated and reacted for 5h at 190 ℃. After the reaction is finished, cooling, centrifuging and drying to obtain a phosphomolybdic heteropoly acid precursor which is recorded as PMo12。
The preparation method of the silver nano material comprises the following steps: mixing a volume of AgNO3Adding 0.2 mol/L aqueous solution and 0.6mol/L sodium citrate solution into 500mL water, stirring, adding 5mmol/L polyvinylpyrrolidone (PVP) solution, mixing, continuously stirring, and rapidly adding freshly prepared NaBH4The aqueous solution (0.1mol/L) was stirred well for 8min, and the mixed solution was placed under a 100W tungsten lamp for irradiation, and the experiment was performed under a dark condition in order to avoid the influence of other light rays on the experiment. Sampling at regular time in the process of the illumination reaction, and carrying out ultraviolet-visible absorption spectrum test on the sample. End of illuminationAnd washing the sample by using absolute ethyl alcohol and deionized water, and centrifuging for later use.
Adjusting the irradiation time of different tungsten filament lamps, taking the silver nano materials prepared under different conditions, mixing, washing and centrifuging for later use; the silver nano material prepared under different conditions is PMo prepared by irradiating the silver nano material for 0h, 8h, 12h, 16h and 20h by using a 100W tungsten lamp according to the mass ratio of 5:1:2:1:112。
The preparation method of the saturated phosphomolybdate/silver nano composite material with the Keggin structure comprises the following steps: will PMo12And after cooling, removing the upper solution, compounding the lower mixed solution with a certain volume of silver nano-particles, continuously stirring for 25min at a certain temperature, finally transferring the mixed solution into a stainless steel reaction kettle with a volume of 15mL and a polytetrafluoroethylene lining, and carrying out reaction heating for 5h at the constant temperature of 190 ℃. After the reaction is finished, cooling the sample to room temperature, centrifuging and drying to obtain the phosphomolybdate/silver nano composite material which is recorded as PMo12/Ag。
Example 3
A preparation method of a visible light full-absorption saturated phosphomolybdate composite material with a Keggin structure comprises the following steps:
A. preparing phosphomolybdate with a saturated Keggin structure;
B. preparing a silver nano material;
C. preparing the saturated phosphomolybdate/silver nano composite material with the Keggin structure.
The phosphomolybdate with the saturated Keggin structure is a phosphomolybdic acid precursor and is marked as PMo12。
The preparation method of the phosphomolybdic heteropoly acid precursor comprises the following steps: 0.4000g (1.65mmol) of sodium molybdate 0.1mL of phosphoric acid, mixing and dissolving with 30mL of deionized water, then placing in a water bath at 85 ℃ for heating and continuously stirring, dropwise adding hydrochloric acid (6mol/L) to adjust the pH value to 2-3 after 30min, continuously stirring at constant temperature for 15min, then adding 0.0400g of cobalt chloride and 0.0200g of phenanthroline to fully react for 8min, dropwise adding saturated sodium carbonate solution to adjust the pH value to 6-7, continuously stirring at constant temperature for 35min, cooling the mixed solution obtained by reaction to the temperature ofAt room temperature, the mixture was finally transferred to a stainless steel reaction kettle with a polytetrafluoroethylene lining, which had a volume of 15mL, and heated at 170 ℃ for 6 hours. After the reaction is finished, cooling, centrifuging and drying to obtain a phosphomolybdic heteropoly acid precursor which is recorded as PMo12。
The preparation method of the silver nano material comprises the following steps: mixing a volume of AgNO3Adding 0.2 mol/L aqueous solution and 0.6mol/L sodium citrate solution into 500mL water, stirring, adding 5mmol/L polyvinylpyrrolidone (PVP) solution, mixing, continuously stirring, and rapidly adding freshly prepared NaBH4The aqueous solution (0.1mol/L) was stirred well for 3min, and the mixed solution was placed under a 100W tungsten lamp for irradiation, and the experiment was performed under a dark condition in order to avoid the influence of other light rays on the experiment. Sampling at regular time in the process of the illumination reaction, and carrying out ultraviolet-visible absorption spectrum test on the sample. And after the illumination is finished, washing the sample by using absolute ethyl alcohol and deionized water, and centrifuging for later use.
The preparation method of the saturated phosphomolybdate/silver nano composite material with the Keggin structure comprises the following steps: will PMo12And after cooling, removing the upper solution, compounding the lower mixed solution with a certain volume of silver nano-particles, continuously stirring for 35min at a certain temperature, finally transferring the mixed solution into a stainless steel reaction kettle with a volume of 15mL and a polytetrafluoroethylene lining, and reacting and heating for 6h at the constant temperature of 170 ℃. After the reaction is finished, cooling the sample to room temperature, centrifuging and drying to obtain the phosphomolybdate/silver nano composite material which is recorded as PMo12/Ag。
The present invention is characterized and analyzed as follows
Characterization of silver nanomaterials
During this experiment, no NaBH was added to the mixed solution4When the solution is colorless, add NaBH4Then the solution turns yellow instantly, and the solution color changes into yellow-blue green-dark blue successively with the prolonging of the illumination time, as shown in figure 1.
As shown in fig. 2, before the light irradiation, the silver nanoparticles have obvious light absorption only at the wavelength of 420nm, and the color of the solution is yellow at this time, and the comparison with the literature shows that the silver nanoparticles are generated in the solution. With the continuous extension of the illumination time, the color of the solution gradually changes to green, a new weak absorption peak (as shown in a figure 3 a) begins to appear at the wavelength of about 790nm, which indicates that the solution gradually generates a new phase silver nano material with a stable structure (as shown in a figure 4-a), and the appearance of the silver nano material is similar to a sheet structure but has an irregular profile as shown by electron microscope characterization. And (3) continuously prolonging the illumination time, continuously deepening the color of the solution into dark blue, obviously blue-shifting an ultraviolet absorption peak, and gradually increasing the intensity (shown as b-d in figure 3), wherein an electron microscope test result shows that the silver nanoparticles in the solution are basically completely converted into silver nano flaky structures (shown as b-d in figure 4). In this process, two weak absorption peaks (as in fig. 3) appeared at around 335nm and 480nm, and the analytical reason was mainly due to out-of-plane and in-plane quadrupole surface plasmon resonance absorption of silver nanoplates. As shown in fig. 3 and 4, as the illumination time is prolonged, the absorption peak of the silver nanosheet is further blue-shifted and has a regular sheet-like structure with a clear boundary, which is mainly because the absorption peak is continuously blue-shifted due to the fact that the angle of the tip is increased and the thickness is reduced as the side length is continuously increased.
According to the analysis of the electron microscope test result, the prepared silver nano flaky structure can move corresponding to the ultraviolet absorption peak. The silver nano-sheet prepared by the subject has obvious ultraviolet absorption between 650-680nm (as shown in a-c in figure 5), and the product is mainly polygonal silver nano-sheet (as shown in a-c in figure 6), the side length is in the range of 50-100nm, and all silver nano-particles in the solution are converted into silver nano-sheet structures.
Characterization of saturated phosphomolybdate with Keggin structure and composite material thereof
2.1 characterization of the Infrared Spectrum
The general structural formula of heteropolyanion of heteropolyacid with Keggin structure is [ XM12O40]n-The structure containing four types of oxygen atoms, in which the hetero atom X is linked to four oxygen atoms, i.e. tetrahedral oxygen Oa(ii) a Oxygen atoms common to the vertices of different trimetal clusters, i.e. bridging oxygens Ob(ii) a Oxygen atoms common to the same trimetal cluster, i.e. bridging oxygens Oc(ii) a Non-common oxygen atoms per octahedron, i.e. terminal oxygen Od. The oxygen atom is connected with the heteroatom or the ligand atom through four bonds which are respectively X-Oa，M-Ob-M，M-Oc-M，M＝Od. The heteropolyacid with a Keggin structure is at 700-1100cm-1Infrared absorption peaks are generated in the fingerprint area. The results of the IR spectroscopy tests on the samples prepared in this section are shown in FIGS. 7 and 8.
PMo12The infrared absorption spectrum of the precursor is shown in fig. 7, and the main absorption peaks are shown in: 1056cm-1，956 cm-1，874cm-1，798cm-1And the result is consistent by comparing the absorption peaks with the absorption peaks of the infrared spectrum of a Keggin structure in the literature. And the four absorption peaks can be assigned as: P-OaStretching and contracting of the bond, Mo ═ OdBond stretching vibration, Mo-ObStretching vibration of Mo bond, Mo-Oc-Mo bond bending vibration. In addition, is located at 1420--1The absorption peaks in the interval can be attributed to the stretching vibration of the C ═ C and C ═ N bonds of phenanthroline. The results show that PMo was prepared12The precursor has a Keggin structure.
PMo12The infrared absorption spectrum of the/Ag sample can be seen from figure 8, at 1056cm-1，956cm-1，874cm-1， 798cm-1There are still significant characteristic absorption peaks in four places, with PMo before recombination12And the infrared spectra of the precursors are consistent, which shows that the composite sample still has a complete Keggin structure.
2.2X-ray diffraction characterization
As can be seen by reference of documents and related data, XRD diffraction peaks of the Keggin structure heteropoly acid mainly appear in four intervals of 7-10 degrees, 16-23 degrees, 25-30 degrees and 31-43 degrees of 2 theta. Prepared PMo is subjected to XRD-7000 type powder X-ray diffractometer12The precursors were tested and the results are shown in fig. 9 and 10;
PMo12as can be seen from fig. 9, the XRD patterns of the precursor show diffraction peaks at 2 θ ═ 7 °, 9 °, 18 °, 26 °, 29 °, and 33 °, which are sequentially distributed in four intervals of the diffraction peaks of the Keggin structure, further indicating that the prepared sample has the Keggin structure.
As shown in FIG. 10, is PMo12The XRD spectrum of the/Ag composite sample shows that when the diffraction peak is 7 degrees, 9 degrees, 18 degrees, 26 degrees, 29 degrees and 33 degrees, the PMo can be determined12A diffraction peak of (a); the diffraction peaks are shown at 38 °, 44 °, 64 °, 77 ° 2 θ, and correspond to four diffraction peaks of silver nanometers, and correspond to four crystal planes (JCPDS: 87-0597) of face-centered cubic silver nanometers (111) (200) (220) (311), and the analysis test results show PMo12the/Ag sample is successfully compounded.
2.3 characterization of UV-Vis absorption Spectroscopy
The light absorption range and the intensity of the prepared sample are characterized by ultraviolet-visible absorption spectrum test, and the specific test results are shown in fig. 11 and 12;
FIG. 11 shows PMo12The ultraviolet absorption spectrogram of the precursor has obvious ultraviolet absorption at the wavelength of 200nm and 260 nm. The ultraviolet absorption peak at a wavelength of 200nm can be assigned as Od-charge transfer transition between Mo and assignment of ultraviolet absorption peak at 260nm as Ob-Mo，Oc-charge transfer transition between Mo. Due to OdAnd Mo exists in a double bond form, so that the transition process is in a high-energy region and is in a band-shaped strong absorption mode. And O isb， OcAnd Mo exist as a single bond, and appear in a low energy region during transition, and show weak band absorption. In addition, the classical heteropolyacid with a Keggin structure has strong light absorption at the wavelength of about 260nm, and the light absorption in other areas is weak. The sample prepared by the experiment has stronger light absorption in the wavelength range of 200-400nm, and compared with the traditional heteropolyacid with a Keggin structure, the light absorption range is expanded.
FIG. 12 is PMo12Ultraviolet absorption spectrogram of the/Ag composite material. The result shows that the light absorption is obviously enhanced in the range of 600-800 nm, and the response activity in the visible light region is improved. Because the band gap widths of the heteropoly acid and the silver nanometer are different, overlapping occurs in the compounding process, the band gap of the composite material is narrowed, and the photoresponse range is enlarged. And PMo in the wavelength range of 200-400nm12The light absorption intensity of the/Ag composite material is kept unchanged, which shows that the composite material still keeps a complete Keggin type structure.
2.4 Electron microscopy characterization
PMo prepared by SEM and TEM couple12Precursor and PMo12The morphology and structural composition of/Ag were characterized and the results are shown in FIG. 13.
As shown in FIG. 13, PMo12SEM and EDS of the precursor are denoted as a, b, PMo12SEM and EDS of the/Ag composite material are marked as c and d. The results show that the samples in the graph a are in relatively uniform block distribution, the particle sizes are all about 50-80nm, but the dispersibility is poor. The P, Mo element is shown in panel b, indicating that the prepared sample is PMo12. The samples in the graph c are uniformly distributed in a block shape, the distribution limit is clear, the diameters are different, and the size is about 100-200 nm. The graph d shows that the sample contains P, Mo and Ag elements, and the composite sample contains silver elements. E.g. graphs e-h, representing PMo12The TEM-EDS element mapping test chart of the/Ag composite material shows that the composite sample contains P, Mo and Ag elements and is uniformly distributed. Test results show that PMo is successfully prepared in the experiment12Nanocomposite PMo of precursor and Ag12/Ag。
III, PMo12Experimental result and analysis of Ag photocatalytic degradation of RhB dye
3.1 PMo12RhB experiment for Ag degradation
Selecting PMo12The photocatalytic conditions of the precursor are as follows: the catalyst dosage is 1.5g/L, the Ph of the solution is 5-6, and the dye concentration is 10 mg/L. Because the silver nano of the sheet structure accounts for a small proportion in the composite catalyst, PMo12The photocatalytic degradation experimental conditions of the/Ag composite sample are carried out, and the results are shown in FIGS. 14 and 15.
As can be seen from FIG. 14, PMo was observed under the same experimental conditions (catalyst amount, solution pH, dye concentration)12The decolorization rate of the Ag composite sample is obviously higher than that of the PMo alone12The decolorization rate of the precursor is as high as 98.75 percent, which shows that PMo12the/Ag composite sample is compared with PMo12The precursor has more excellent photocatalytic performance. The main reason is PMo12Photo-excitation generates photo-generated electrons (e)-) And photo-generated holes (h)+) The photo-generated electrons and holes can generate oxygen after rapidly diffusing to the surface of the catalystThe organic dye is degraded by the reduction reaction. But during photocatalytic degradation, e-And h+Coupling is very easy to occur, resulting in the reduction of the efficiency of the photocatalytic reaction. At PMo12In the Ag/Ag composite sample, the addition of the silver nano can inhibit the coincidence of photo-generated electrons and holes, accelerate the separation of the photo-generated electrons and the holes, fully play the synergistic effect of the photo-generated electrons and the holes and enhance the photocatalytic performance.
3.2 PMo12Ag recycling experiment
By recycling PMo repeatedly12the/Ag composite sample is used for carrying out a photocatalytic degradation experiment on the RhB dye to evaluate PMo12And catalyzing and recycling the/Ag composite sample. At PMo12The dosage of Ag is 1.5g/L, and the concentration of RhB dye is 10mg/L through photocatalysis under the photocatalysis condition that the pH value of the solution is 5-6. After each catalytic reaction, the catalyst is washed and stirred for a plurality of hours by absolute ethyl alcohol, then washed by deionized water, centrifugally separated, and the lower layer sediment is the catalyst sample, and finally the catalyst is dried for 4-5 hours at the temperature of 60 ℃. The results of three cycles of the washed catalyst used for the next catalytic degradation under the same experimental conditions are shown in fig. 16.
From FIG. 16, when PMo is used12PMo is carried out after three cycles when the RhB dye is circularly catalyzed and degraded by the Ag composite sample12The Ag composite photocatalyst has small activity loss. At the end of the third catalytic cycle, the rhodamine B dye decolorization rate can still reach about 94.35%.
3.3 Mo12Structural analysis before and after photocatalysis of Ag composite material
Using PMo12In the process of carrying out a photocatalytic cycle experiment on the/Ag composite material, after each cycle catalysis, the catalyst is washed by absolute ethyl alcohol and distilled water, centrifugally separated, precipitated on the lower layer, dried and stored for later use. And (3) performing infrared spectrum characterization on the catalyst recycled each time, and observing whether the Keggin structure of the sample is kept complete in the catalysis process, wherein the specific test result is shown in FIG. 17.
As can be seen from FIG. 17, after three photocatalytic degradation cycle experiments, PMo12Ag complexThe infrared spectrogram of the composite sample is consistent with the position of the absorption peak of the sample before catalysis, which shows that the heteropolyacid structure of the composite photocatalyst is not changed before and after catalysis, and the complete Keggin structure is still reserved.
Four, PMo12And PMo12Mechanism research of Ag photocatalytic degradation of RhB dye
To confirm the efficient separation of photo-generated charge carriers and the enhancement of the photocatalytic activity of the prepared catalyst, we performed fluorescence spectroscopy on the prepared samples. Under the action of light excitation, energy level transition of substances can occur to generate electrons and holes, and the photogenerated electrons and holes can respectively occupy empty orbitals of a conduction band and a valence band to form a quasi-equilibrium state. In the quasi-equilibrium state, light is emitted only after the electron-hole recombination. Therefore, the higher the luminous intensity of the substance, the higher the probability of electron-hole recombination. The experimental test measures the emission spectrum of the prepared sample with the excitation wavelength of 340 nm. From FIG. 18, PMo12And PMo12The emission of fluorescence of/Ag at 676nm is similar to that of PMo12Comparison of precursors, PMo12The spectral peak intensity of the/Ag composite material is obviously reduced, which shows that the recombination of photo-generated electrons and holes is inhibited, the recombination probability is reduced, and the PMo is further proved12The photocatalytic performance of the/Ag composite catalyst is superior to that of PMo12And (3) precursor.
To investigate PMo further12And PMo12The hole and free radical trapping experiment is carried out according to the mechanism of degrading RhB dye by the Ag composite sample through photocatalysis. The heteropolyacid salt generates various active species (photogenerated holes h +, peroxy free radicals. O) after being excited by light2 -Hydroxyl radical. OH), it is necessary to investigate which active species plays a major role in the photocatalytic reaction, so in this experiment, triethanolamine (TEOA, h) was used+Quenchers), isopropanol (IPA,. OH Capture) and piperidinol oxide (4-hydroxy-TEMPO,. O)2 -Quenching agent) is added into the photocatalytic system to carry out the reaction. Respectively adding 1mmol of quencher into the catalytic system, sampling at regular time and testing, analyzing the influence of the three quenchers on the photocatalytic effect according to the test results, wherein the test results are shown in the figure19, respectively.
The results show that the degree of decolorization reduction is small after Isopropanol (IPA) is added, which indicates that the existence amount of hydroxyl free radicals in the reaction system is small and the catalytic action is weak, and the decolorization ratio is obviously reduced after Triethanolamine (TEOA) and piperidinol oxide (TEMPO) are added. It can thus be demonstrated that PMo is used under conditions of irradiation with visible light12Oxygen free radical (. O) in process of degrading RhB by Ag composite photocatalyst2 -) And photo-generated holes (h)+) Two active species play a major role.
When visible light irradiates PMo12When the/Ag composite material is used, PMo can be simultaneously excited12And silver nanometers. PMo12Excited by light to generate electrons and holes, electrons can be emitted from PMo12Excites and transfers to the Conduction Band (CB) and leaves a hole in VB. Then, the photogenerated holes can directly oxidize the RhB molecules in the solution, and partial photogenerated holes can react with electron donor water molecules to generate hydroxyl radicals (. OH) to oxidize the RhB molecules in the aqueous solution. But at PMo12The photoproduction electrons and holes in the system are easy to couple, thereby inhibiting PMo12And (4) carrying out a catalytic reaction. After being excited by light, the silver nano-particles can show the plasma resonance absorption (SPR) phenomenon to generate photo-generated electrons and holes, and the silver nano-particles can cause strong local electromagnetic field due to the SPR phenomenon to enable the holes of the silver nano-particles and PMo12The electrons generated in (1) form electron-hole pairs, thereby accelerating PMo12Separation of photogenerated electrons and holes in the precursor. Photo-generated electron slave PMo12Transferred to nano silver and recombined with the holes generated by the silver nano under the excitation of light, and then the plasma electrons of the silver nano can be absorbed by the electron acceptor O on the surface2Trapping, forming O2 -Active substances can directly oxidize RhB molecules into degradation products. Therefore, O is mainly promoted in the photocatalytic degradation process2 -And photogenerated holes h+The hydroxyl radical OH plays a minor role.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (6)
1. A preparation method of a visible light full-absorption saturated phosphomolybdate composite material with a Keggin structure is characterized by comprising the following steps:
A. preparing phosphomolybdate with a saturated Keggin structure;
B. preparing a silver nano material;
C. preparing a saturated phosphomolybdate/silver nano composite material with a Keggin structure;
the phosphomolybdate with the saturated Keggin structure is a phosphomolybdic acid precursor and is marked as PMo12。
2. The preparation method of the visible light full-absorption saturated type phosphomolybdate composite material with Keggin structure as claimed in claim 1, wherein the preparation method of the phosphomolybdic heteropoly acid precursor comprises the following steps: mixing and dissolving sodium molybdate and phosphoric acid with deionized water, then placing the mixture in a water bath for heating at 80-90 ℃ and continuously stirring, dropwise adding hydrochloric acid to adjust the pH value to 2-3 after 25-35min, continuously stirring at constant temperature for 8-15min, then adding cobalt chloride and phenanthroline to fully react for 8-15min, dropwise adding a saturated sodium carbonate solution to adjust the pH value to 6-7, continuously stirring at constant temperature for 25-35min, cooling the mixed solution obtained by the reaction to room temperature, finally transferring the mixed solution to a stainless steel reaction kettle with a polytetrafluoroethylene lining, and heating and reacting for 5-6h at 190 ℃ with 170-; and after the reaction is finished, cooling, centrifuging and drying to obtain the phosphomolybdic heteropoly acid precursor.
3. The preparation method of the visible light full-absorption saturated type Keggin structure phosphomolybdate composite material as claimed in claim 1, wherein the preparation method of the silver nano material comprises the following steps: mixing a volume of AgNO3Adding the aqueous solution and the sodium citrate solution into water, stirring uniformly, and adding the polyvinyl pyrroleThe alkanone solution was mixed with constant agitation and rapid addition of freshly prepared NaBH4Fully stirring the aqueous solution for 3-8min, and placing the mixed solution under a 100W tungsten lamp for irradiation; and after the illumination is finished, washing the sample by using absolute ethyl alcohol and deionized water, and centrifuging for later use.
4. The method for preparing the visible light full-absorption saturated Keggin phosphomolybdate composite material according to claim 1, wherein the method for preparing the saturated Keggin phosphomolybdate/silver nano composite material comprises the following steps: will PMo12After cooling, removing the upper solution, compounding the lower mixed solution with a certain volume of silver nano-particles, continuously stirring for 25-35min at a certain temperature, finally transferring the mixed solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, and reacting and heating for 5-6h at the constant temperature of 190 ℃ in 170-; after the reaction is finished, cooling the sample to room temperature, centrifuging and drying to obtain the phosphomolybdate/silver nano composite material which is recorded as PMo 12/Ag.
5. The method for preparing the visible light full-absorption saturated Keggin phosphomolybdate composite material as claimed in claim 3, wherein in the step B, the irradiation time of different tungsten filament lamps is adjusted, silver nano-materials prepared under different conditions are taken and mixed, and then the step C is carried out.
6. The method for preparing the visible light full-absorption saturated Keggin structure phosphomolybdate composite material as claimed in claim 5, wherein the silver nano-materials prepared under different conditions are silver nano-materials obtained after 100W tungsten lamps are adopted for irradiation for 0h, 8h, 12h, 16h and 20h respectively.
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Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006038045A1 (en) * | 2004-10-05 | 2006-04-13 | National Center Of Scientific Research 'demokritos' | Size-selective synthesis of metal nanoparticles |
| CN1798858A (en) * | 2003-04-02 | 2006-07-05 | 西北大学 | Methods of controlling nanoparticle growth |
| WO2007145184A1 (en) * | 2006-06-13 | 2007-12-21 | Osaka Titanium Technologies Co., Ltd. | Lighting equipment excelling in air purification |
| CN102500366A (en) * | 2011-11-03 | 2012-06-20 | 合肥美菱股份有限公司 | Photo-catalytic nanomaterial |
| CN102554258A (en) * | 2012-02-03 | 2012-07-11 | 济南大学 | Method for preparing metal silver nanostructure in water solution |
| CN104941662A (en) * | 2015-06-15 | 2015-09-30 | 桂林理工大学 | Preparation method of Ag/BFeO3 compound photocatalyst |
| CN105944720A (en) * | 2016-05-05 | 2016-09-21 | 同济大学 | Preparation method of Ag nanosheet/SnO2 nanorod nanomaterial photocatalyst |
| WO2017036221A1 (en) * | 2015-08-31 | 2017-03-09 | 河海大学 | Preparation and use of silver-modified spiral titanium dioxide nanofibre photocatalyst |
| CN107159264A (en) * | 2017-04-01 | 2017-09-15 | 中国计量大学 | A kind of high-efficient full-spectrum response CuS/ graphene composite photocatalysts and preparation method thereof |
| CN107758639A (en) * | 2017-10-13 | 2018-03-06 | 东北电力大学 | The preparation of Keggin-type saturation phosphomolybdate and its covering material and photocatalytic applications |
| CN107824204A (en) * | 2017-11-07 | 2018-03-23 | 武汉大学 | The preparation method of Efficient Z-type photochemical catalyst based on up-conversion luminescence |
| CN109270052A (en) * | 2018-11-15 | 2019-01-25 | 云南大学 | A kind of uric acid detection method based on silver nanoparticle triangular plate |
| CN111282566A (en) * | 2018-12-06 | 2020-06-16 | 天津科技大学 | Preparation method of silver nanoprism capable of improving photocatalytic degradation capability of titanium dioxide on organic pollutants in wastewater |
| CN111484843A (en) * | 2020-02-21 | 2020-08-04 | 南京理工大学 | Composite nano-particle for enhancing full-spectrum absorption characteristic of sunlight |
-
2020
- 2020-12-31 CN CN202011639610.8A patent/CN113145170B/en active Active
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1798858A (en) * | 2003-04-02 | 2006-07-05 | 西北大学 | Methods of controlling nanoparticle growth |
| WO2006038045A1 (en) * | 2004-10-05 | 2006-04-13 | National Center Of Scientific Research 'demokritos' | Size-selective synthesis of metal nanoparticles |
| WO2007145184A1 (en) * | 2006-06-13 | 2007-12-21 | Osaka Titanium Technologies Co., Ltd. | Lighting equipment excelling in air purification |
| CN102500366A (en) * | 2011-11-03 | 2012-06-20 | 合肥美菱股份有限公司 | Photo-catalytic nanomaterial |
| CN102554258A (en) * | 2012-02-03 | 2012-07-11 | 济南大学 | Method for preparing metal silver nanostructure in water solution |
| CN104941662A (en) * | 2015-06-15 | 2015-09-30 | 桂林理工大学 | Preparation method of Ag/BFeO3 compound photocatalyst |
| WO2017036221A1 (en) * | 2015-08-31 | 2017-03-09 | 河海大学 | Preparation and use of silver-modified spiral titanium dioxide nanofibre photocatalyst |
| CN105944720A (en) * | 2016-05-05 | 2016-09-21 | 同济大学 | Preparation method of Ag nanosheet/SnO2 nanorod nanomaterial photocatalyst |
| CN107159264A (en) * | 2017-04-01 | 2017-09-15 | 中国计量大学 | A kind of high-efficient full-spectrum response CuS/ graphene composite photocatalysts and preparation method thereof |
| CN107758639A (en) * | 2017-10-13 | 2018-03-06 | 东北电力大学 | The preparation of Keggin-type saturation phosphomolybdate and its covering material and photocatalytic applications |
| CN107824204A (en) * | 2017-11-07 | 2018-03-23 | 武汉大学 | The preparation method of Efficient Z-type photochemical catalyst based on up-conversion luminescence |
| CN109270052A (en) * | 2018-11-15 | 2019-01-25 | 云南大学 | A kind of uric acid detection method based on silver nanoparticle triangular plate |
| CN111282566A (en) * | 2018-12-06 | 2020-06-16 | 天津科技大学 | Preparation method of silver nanoprism capable of improving photocatalytic degradation capability of titanium dioxide on organic pollutants in wastewater |
| CN111484843A (en) * | 2020-02-21 | 2020-08-04 | 南京理工大学 | Composite nano-particle for enhancing full-spectrum absorption characteristic of sunlight |
Non-Patent Citations (4)
| Title |
|---|
| ABBAS AMINI RT AL.: "One-pot facile simultaneous in situ synthesis of", 《THE ROYAL SOCIETY OF CHEMISTRY》 * |
| HANG ZHAO ET AL.: "Noble metal-like behavior of plasmonic Bi particles deposited on", 《CHINESE JOURNAL OF CATALYSIS》 * |
| JI ZHOU ET AL.: "Growth of Tetrahedral Silver Nanocrystals in Aqueous Solution and", 《AMERICAN CHEMICAL SOCIETY》 * |
| JING AN ET AL.: "Photoinduced Shape Evolution: From Triangular to Hexagonal Silver Nanoplates", 《AMERICAN CHEMICAL SOCIETY》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114984957A (en) * | 2022-07-06 | 2022-09-02 | 东北电力大学 | Preparation method of heteropolyacid photocatalyst capable of being magnetically regulated |
| CN114984957B (en) * | 2022-07-06 | 2023-09-01 | 东北电力大学 | Preparation method of heteropolyacid photocatalyst capable of being magnetically regulated and controlled |
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