CN111729677B - Ag/BiOCl/AgIO 3 Heterojunction photocatalyst and preparation method and application thereof - Google Patents
Ag/BiOCl/AgIO 3 Heterojunction photocatalyst and preparation method and application thereof Download PDFInfo
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- BWOROQSFKKODDR-UHFFFAOYSA-N oxobismuth;hydrochloride Chemical compound Cl.[Bi]=O BWOROQSFKKODDR-UHFFFAOYSA-N 0.000 title claims abstract description 245
- 239000011941 photocatalyst Substances 0.000 title claims abstract description 73
- 238000002360 preparation method Methods 0.000 title claims abstract description 14
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- PYWVYCXTNDRMGF-UHFFFAOYSA-N rhodamine B Chemical compound [Cl-].C=12C=CC(=[N+](CC)CC)C=C2OC2=CC(N(CC)CC)=CC=C2C=1C1=CC=CC=C1C(O)=O PYWVYCXTNDRMGF-UHFFFAOYSA-N 0.000 claims description 15
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- DKGAVHZHDRPRBM-UHFFFAOYSA-N Tert-Butanol Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 description 3
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- RKTYLMNFRDHKIL-UHFFFAOYSA-N copper;5,10,15,20-tetraphenylporphyrin-22,24-diide Chemical compound [Cu+2].C1=CC(C(=C2C=CC([N-]2)=C(C=2C=CC=CC=2)C=2C=CC(N=2)=C(C=2C=CC=CC=2)C2=CC=C3[N-]2)C=2C=CC=CC=2)=NC1=C3C1=CC=CC=C1 RKTYLMNFRDHKIL-UHFFFAOYSA-N 0.000 description 1
- YXKMMRDKEKCERS-UHFFFAOYSA-N cyazofamid Chemical compound CN(C)S(=O)(=O)N1C(C#N)=NC(Cl)=C1C1=CC=C(C)C=C1 YXKMMRDKEKCERS-UHFFFAOYSA-N 0.000 description 1
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- TYIXMATWDRGMPF-UHFFFAOYSA-N dibismuth;oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Bi+3].[Bi+3] TYIXMATWDRGMPF-UHFFFAOYSA-N 0.000 description 1
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- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 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
- B01J27/06—Halogens; Compounds thereof
-
- B01J35/39—
-
- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/34—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation
- B01J37/341—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation
- B01J37/344—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation of electromagnetic wave energy
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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
- 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
- C02F2101/34—Organic compounds containing oxygen
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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
- C02F2101/38—Organic compounds containing nitrogen
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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
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/30—Wastewater or sewage treatment systems using renewable energies
- Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy
Abstract
The invention provides Ag/BiOCl/AgIO 3 The preparation method comprises the following steps of 1, preparing a suspension from BiOCl powder with an exposed (001) crystal face by using deionized water, and adding AgNO 3 Powder and NaIO 3 Uniformly mixing the powder to obtain a mixed system; step 2, carrying out illumination reaction on the mixed system under a light source to obtain a reaction solution; step 3, separating and drying the product in the reaction solution to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst. The electrons of Ag can be transferred to BiOCl to raise the Fermi level of BiOCl, and BiOCl and AgIO with I-type energy band structure 3 The structure is converted into a direct Z-shaped (staggered) heterojunction structure, so that the reduction capability of photoproduction electrons and the oxidation capability of photoproduction holes are improved, the dissociation of excitons at a heterojunction interface is accelerated, and the heterojunction photocatalyst can effectively degrade organic pollutants.
Description
Technical Field
The invention belongs to the field of semiconductor photocatalytic functional materials, and particularly relates to Ag/BiOCl/AgIO 3 A heterojunction photocatalyst, a preparation method and application thereof.
Background
In recent years, semiconductor photocatalysis technology has a wide application prospect in the aspect of controlling environmental pollution, and is receiving attention of researchers.
BiOCl is a layered structure consisting of a bismuth oxide layer and a chlorine atomic layer, and photo-generated electrons and holes are easy to have strong interaction in the limited layered structure to generate new photo-generated species-excitons, so that the carriers in the BiOCl are not obviously separated, and the photocatalysis performance is not ideal. To facilitate exciton dissociation, a suitable heterojunction structure can be constructed that allows efficient dissociation of excitons into free electrons and holes at the heterojunction interface. In addition, biOCl is a wide bandgap semiconductor that responds only to ultraviolet light. Aiming at the defects of weak absorption of BiOCl visible light, unobvious separation of photon-generated carriers and the like, noble metal can be loaded on the surface and a heterojunction can be constructed to modify the surface. Among the numerous noble metals, ag is the most economical and noble metal having a strong Surface Plasmon Resonance (SPR) effect, which enhances the absorption of semiconductors in the visible region. In recent years, the Z-type heterojunction has been widely studied because it can not only retain the strong reduction and oxidation potentials of a semiconductor but also accelerate exciton dissociation at the heterojunction interface.
In conclusion, under the action of the SPR effect of Ag and the Z-type heterojunction, the visible light absorption of BiOCl can be enhanced, the dissociation of excitons can be accelerated, and the effective separation of photo-generated charges can be realized. Therefore, it is necessary to prepare a heterojunction photocatalyst based on BiOCl and Ag, but there is no report on the preparation.
Disclosure of Invention
Aiming at the prior artIn the problem, the invention provides Ag/BiOCl/AgIO 3 The heterojunction photocatalyst, the preparation method and the application thereof have the advantages of low cost and simple operation, and can be used for degrading organic pollutants.
The invention is realized by the following technical scheme:
Ag/BiOCl/AgIO 3 The preparation method of the heterojunction photocatalyst comprises the following steps,
Preferably, in the step 1, deionized water is added into the BiOCl powder with the (001) crystal face exposed, and the mixture is stirred at room temperature for 30-40 min to obtain a suspension.
Preferably, biOCl powder and AgNO in step 1 3 Powder and NaIO 3 The mass ratio of the powder is 0.3: (0.01-0.05): (0.05-0.3).
Preferably, biOCl powder and AgNO in step 1 3 Powder and NaIO 3 The concentration of the powder in the mixed system is expressed in g/mL, and the proportion is (5.00-7.50): (0.17-1.25): (0.83-7.50).
Preferably, the time of the light reaction in the step 2 is 2 to 3 hours.
Preferably, in step 2, the mixed system is reacted in a photochemical reactor.
Ag/BiOCl/AgIO of any one of the above 3 Ag/BiOCl/AgIO obtained by preparation method of heterojunction photocatalyst 3 A heterojunction photocatalyst.
Further, the Ag/BiOCl/AgIO 3 The heterojunction photocatalyst is direct Z-type heterojunction photocatalyst, wherein Ag and AgIO 3 Are deposited on the (001) crystal face of BiOCl.
Ag/BiOCl/AgIO 3 The application of the heterojunction photocatalyst in degrading rhodamine B under sunlight and near infrared light.
Compared with the prior art, the invention has the following beneficial technical effects:
the invention relates to Ag/BiOCl/AgIO 3 The preparation method of the heterojunction photocatalyst comprises the steps of preparing a suspension from BiOCl powder with an exposed (001) crystal face, and adding AgNO 3 Powder and NaIO 3 The powder is subjected to illumination reaction, and the product is separated and dried to obtain Ag/BiOCl/AgIO 3 Heterojunction photocatalyst, ag/BiOCl/AgIO 3 The material belongs to a Z-type heterojunction, and the layered structure of BiOCl endows the material with a strong exciton effect, namely, most of photo-generated electrons and holes can be combined to form a large number of primary excitons under illumination due to coulomb action force, and only few photo-generated electrons can be transferred to a (001) crystal face of the BiOCl; the SPR effect of Ag can enhance the light absorption of the semiconductor; the Z-type heterojunction can keep the strong oxidation potential and the strong reduction potential of a semiconductor on one hand, and on the other hand, the Z-type heterojunction can accelerate excitons to be dissociated into free electrons and holes at the heterojunction interface, so that the establishment of the Z-type heterojunction is beneficial to exciton separation. Under illumination, only few photo-generated electrons migrate to the (001) crystal face of BiOCl, so that reduction of Ag is insufficient + Thus, ag + And IO 3 - Will react preferentially to generate AgIO 3 。AgIO 3 The nucleus further attracts Ag + Forming an adsorption layer to form AgIO 3 ·Ag + Colloidal particles, agIO 3 ·Ag + Colloidal particles adsorbing NO in solution 3 - Finally, generating AgIO 3 ·Ag + ·NO 3 - And (4) micelle. According to DLVO theory, agIO 3 ·Ag + Attracted to the (001) crystal plane of BiOCl, which has few electrons, by van der waals forces. AgIO 3 Self-assembled into irregular sheets to be adsorbed on the (001) crystal face of BiOCl to form two-dimensional AgIO 3 And two-dimensional BiOCl interface. And Ag + Attracted by a small number of electrons on the BiOCl (001) crystal face and reduced to Ag. Finally, agIO 3 And Ag are deposited on the (001) crystal face of BiOCl to prepare Ag/BiOCl/AgIO 3 A heterojunction photocatalyst. Although BiOCl and AgIO 3 Is type I(i.e., embedded) band structure, but since Ag has a work function less than BiOCl, the Ag electrons will transfer to BiOCl, raising the Fermi level of BiOCl, biOCl and AgIO of type I band structures 3 The structure is converted into a direct Z-shaped (staggered) heterojunction structure, so that the reduction capability of photogenerated electrons and the oxidation capability of photogenerated holes are improved, the dissociation of excitons at a heterojunction interface is accelerated, and the heterojunction photocatalyst can effectively degrade organic pollutants.
Under the irradiation of light, free electrons in Ag compete for holes in primary excitons in BiOCl to form secondary excitons and release electrons in the primary excitons. Electrons released by the primary exciton reach a BiOCl conduction band to participate in reduction reaction, and a BiOCl valence band hole and AgIO 3 Conduction band electron recombination, retention of BiOCl conduction band electron with strong reduction capability and AgIO with strong oxidation capability 3 The valence band hole not only accelerates the dissociation of excitons in the BiOCl, but also improves the redox capability of the material.
The invention proves that the heterojunction photocatalyst has high degradation rate on rhodamine B under sunlight through simulated sunlight, can effectively degrade rhodamine B under near infrared light, and has good application prospect.
Drawings
FIG. 1 is an XRD pattern of products prepared in comparative examples 1 to 2 and examples 1 to 6 according to the present invention.
Fig. 2 is an enlarged view of fig. 1 at 2 θ =10-15 °.
Fig. 3 is an enlarged view of fig. 1 at 2 θ =22-28 °.
FIG. 4 is a Raman diagram of products prepared in comparative examples 1 to 2 and examples 1 to 6 of the present invention.
FIG. 5 is a graph of UV-vis DRS of products prepared in comparative examples 1 to 2 and examples 1 to 6 according to the present invention.
FIG. 6 is an XPS plot of a product prepared in example 4 of the present invention.
Fig. 7 is an SEM image of the product prepared in comparative example 1 of the present invention.
FIG. 8 is an HRTEM image of the product prepared in comparative example 1 of the present invention.
FIG. 9 is an SEM image of a product prepared by comparative example 2 of the present invention.
FIG. 10 is an SEM photograph of a product prepared in example 4 of the present invention.
FIG. 11 shows Ag/BiOCl/AgIO prepared by the present invention 3 A diagram of the mechanism of heterojunction photocatalyst formation.
FIG. 12 is a PL diagram of products prepared in comparative examples 1 to 2 and examples 1 to 6 of the present invention.
FIG. 13 is a graph showing photocurrents i-t of products prepared in comparative examples 1 to 2 and examples 1 to 6 of the present invention.
FIG. 14 is EIS charts of electrochemical impedance spectra of products prepared in comparative examples 1 to 2 and examples 1 to 6 of the present invention.
FIG. 15 is a graph showing the removal rate of rhodamine B and the capture of active species in simulated sunlight (500W) for the products prepared in comparative examples 1 to 2 and examples 1 to 6 of the present invention.
FIG. 16 is a graph showing the rhodamine B removal rate of the product prepared in example 4 under the irradiation of near-infrared monochromatic light (850 nm,940nm and 1100 nm).
FIG. 17 is a graph of the work function of Ag calculated by DFT theory.
Fig. 18 is a graph of the work function of BiOCl calculated by DFT theory.
FIG. 19 is a graph of the work function of Ag (001)/BiOCl (001) calculated by DFT theory.
FIG. 20 is a schematic diagram of electron transfer after interface formation between Ag and BiOCl.
FIG. 21 shows Ag/BiOCl/AgIO prepared by the present invention 3 A photocatalytic mechanism diagram of a heterojunction photocatalyst.
Detailed Description
The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.
The invention uses Bi (NO) 3 ) 3 ·5H 2 Preparing BiOCl with an exposed (001) crystal face by a hydrothermal method with O as a Bi source and NaCl as a Cl source; with AgNO 3 As a source of Ag, naIO 3 Is IO 3 - The source is prepared into Ag/BiOCl/AgIO by adopting a light reduction method 3 A heterojunction photocatalyst.
The Ag/BiOCl/AgIO of the invention 3 The preparation method of the heterojunction photocatalyst concretely comprises the following steps:
under illumination, ag + And IO 3 - Will react preferentially to form AgIO 3 。AgIO 3 The nucleus further attracts Ag + Forming an adsorption layer to form AgIO 3 ·Ag + Colloidal particles, agIO 3 ·Ag + Colloidal particles for adsorbing NO in solution 3 - Finally, generating AgIO 3 ·Ag + ·NO 3 - And (4) micelle. According to DLVO theory, agIO 3 ·Ag + Attracted to the (001) crystal plane of BiOCl, which has few electrons, by van der waals forces. AgIO 3 Self-assembled into irregular sheets to be adsorbed on the (001) crystal face of BiOCl to form two-dimensional AgIO 3 And two-dimensional BiOCl interface. And Ag + Attracted by a small number of electrons on the BiOCl (001) crystal face and reduced to Ag. Finally, agIO 3 And Ag are deposited on the (001) crystal face of BiOCl,preparing Ag/BiOCl/AgIO 3 A heterojunction photocatalyst. Although BiOCl and AgIO 3 Is of I-type (embedded) energy band structure, but because the work function of Ag is less than that of BiOCl, the electrons of Ag can be transferred to BiOCl to raise the Fermi level of BiOCl, and the BiOCl and AgIO of I-type (embedded) energy band structure 3 And the structure is converted into a direct Z-type (staggered) heterojunction structure.
Under the irradiation of light, free electrons in Ag compete for holes in the primary exciton in BiOCl to form a secondary exciton, and electrons in the primary exciton are released. Electrons released by the primary exciton reach a BiOCl conduction band to participate in reduction reaction, and a BiOCl valence band hole and AgIO 3 Conduction band electron recombination, retention of BiOCl conduction band electron with strong reducing power and AgIO with strong oxidizing power 3 The valence band hole not only accelerates the dissociation of excitons in the BiOCl, but also improves the redox capability of the material.
Then filtering the reaction solution, washing the obtained precipitate with deionized water and absolute ethyl alcohol for 3 times respectively, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
The composite photocatalyst can be used for degrading organic pollutants.
The Ag/BiOCl/AgIO of the invention 3 The preparation of the heterojunction photocatalyst was carried out as follows:
example 1:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
step 2:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 60mL of water, stirring at room temperature for 30min to obtain (001) crystal face BiOCl suspension A, and adding 0.03g of AgNO 3 And 0.05g NaIO 3 Adding into the suspension A to obtain a mixturePlacing the mixed system B in an XPA-3 photochemical reactor for carrying out illumination reduction reaction for 2.5h to obtain reaction liquid, filtering the reaction liquid, respectively cleaning precipitates for 3 times by using deionized water and absolute ethyl alcohol, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 2:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
step 2:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 60mL of water, stirring at room temperature for 30min to obtain (001) crystal face BiOCl suspension A, and adding 0.03g of AgNO 3 And 0.10g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reaction instrument for carrying out illumination reduction reaction for 2.5h to obtain reaction liquid, filtering the reaction liquid, respectively cleaning the precipitate with deionized water and absolute ethyl alcohol for 3 times, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 3:
step 1: 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
and 2, step:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 60mL of water, stirring at room temperature for 30min to obtain (001) crystal face BiOCl suspension A, and adding 0.03g of AgNO 3 And 0.15g NaIO 3 Adding intoObtaining a mixed system B in the suspension A, placing the mixed system B in an XPA-3 photochemical reaction instrument for carrying out illumination reduction reaction for 2.5 hours to obtain reaction liquid, filtering the reaction liquid, respectively cleaning precipitates with deionized water and absolute ethyl alcohol for 3 times, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 4:
step 1: 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
and 2, step:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 60mL of water, stirring at room temperature for 30min to obtain (001) crystal face BiOCl suspension A, and adding 0.03g of AgNO 3 And 0.20g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reactor for illumination reduction reaction for 2.5h to obtain a reaction solution, filtering the reaction solution, washing the precipitate for 3 times by deionized water and absolute ethyl alcohol respectively, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 5:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
and 2, step:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 60mL of water, stirring at room temperature for 40min to obtain (001) crystal face BiOCl suspension A, and adding 0.03g of AgNO 3 And 0.25g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reactor for illumination reduction reaction for 2.5h to obtain a reaction solution, filtering the reaction solution, washing the precipitate for 3 times by deionized water and absolute ethyl alcohol respectively, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 6:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
step 2:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 60mL of water, stirring at room temperature for 40min to obtain (001) crystal face BiOCl suspension A, and adding 0.03g of AgNO 3 And 0.30g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reactor for illumination reduction reaction for 2.5h to obtain a reaction solution, filtering the reaction solution, washing the precipitate for 3 times by deionized water and absolute ethyl alcohol respectively, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 7:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL deionized water, stirring at room temperature for 2 hours to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting at 160 ℃ for 18 hours, cooling the reaction kettle to room temperature after the reaction is finished, taking out the reaction kettle, standing to remove a supernatant, washing precipitates with deionized water and absolute ethyl alcohol respectively for 3 times, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
step 2:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 40mL of water, and stirring at room temperature for 30min to obtain (001) crystal face BiOClSuspension A, 0.03g AgNO 3 And 0.20g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reactor for 2h of illumination reduction reaction to obtain a reaction solution, filtering the reaction solution, respectively cleaning precipitates with deionized water and absolute ethyl alcohol for 3 times, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 8:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
and 2, step:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 50mL of water, stirring at room temperature for 35min to obtain (001) crystal face BiOCl suspension A, and adding 0.03g of AgNO 3 And 0.20g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reactor for illumination reduction reaction for 2.5h to obtain a reaction solution, filtering the reaction solution, washing the precipitate for 3 times by deionized water and absolute ethyl alcohol respectively, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 9:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
and 2, step:
0.3g of BiOCl powder with exposed (001) crystal face is dissolved in 60mL of water and stirred at room temperatureStirring for 35min to obtain BiOCl suspension A with crystal face (001), adding 0.01g AgNO 3 And 0.20g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reactor for illumination reduction reaction for 3h to obtain a reaction solution, filtering the reaction solution, respectively cleaning precipitates with deionized water and absolute ethyl alcohol for 3 times, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Example 10:
step 1: adding 8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL deionized water, stirring at room temperature for 2 hours to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting at 160 ℃ for 18 hours, cooling the reaction kettle to room temperature after the reaction is finished, taking out the reaction kettle, standing to remove a supernatant, washing precipitates with deionized water and absolute ethyl alcohol respectively for 3 times, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
step 2:
dissolving 0.3g of exposed (001) crystal face BiOCl powder in 60mL of water, stirring at room temperature for 40min to obtain (001) crystal face BiOCl suspension A, and adding 0.05g of AgNO 3 And 0.20g NaIO 3 Adding into the suspension A to obtain a mixed system B, placing the mixed system B in an XPA-3 photochemical reactor for 2h of illumination reduction reaction to obtain a reaction solution, filtering the reaction solution, respectively cleaning precipitates with deionized water and absolute ethyl alcohol for 3 times, and drying at 70 ℃ to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
Comparative example 1
8mmol of Bi (NO) 3 ) 3 ·5H 2 Dissolving O and 8mmol NaCl in 48mL of deionized water, stirring for 2h at room temperature to obtain a reaction precursor solution, transferring the precursor solution to a hydrothermal reaction kettle, reacting for 18h at 160 ℃, taking out the reaction kettle after the temperature is reduced to room temperature after the reaction is finished, standing to remove a supernatant, washing precipitates for 3 times by using the deionized water and absolute ethyl alcohol respectively, drying at 70 ℃, and grinding to obtain exposed (001) crystal face BiOCl powder;
comparative example 2
0.2g of NaIO 3 And 0.03g AgNO 3 Dissolving in 60mL deionized water, stirring at room temperature for 3h, standing to remove supernatant, washing precipitate with deionized water and anhydrous ethanol for 3 times, drying at 70 deg.C, and grinding to obtain AgIO 3 Powder;
the above conclusions and mechanisms are specifically explained below.
FIG. 1 shows Ag/BiOCl/AgIO prepared by the present invention 3 XRD pattern of the heterojunction photocatalyst. Wherein a and b are BiOCl and AgIO synthesized according to comparative examples 1 and 2, respectively 3 And c, d, e, f, g and h are photocatalysts synthesized according to example 1, example 2, example 3, example 4, example 5 and example 6, respectively. As shown in FIG. 1, agIO 3 And diffraction peaks of BiOCl respectively correspond to the orthogonal phase AgIO 3 And tetragonal BiOCl, which shows strong and sharp diffraction peaks, shows that the crystal planes (001), (002) and (003) have high crystallinity, and the diffraction peaks of the other crystal planes are obviously higher than those of the rest crystal planes, which indicates that the BiOCl exposes the (001) crystal plane. All Ag/BiOCl/AgIO 3 All the photocatalysts contain AgIO 3 And the characteristic diffraction peak of BiOCl proves that Ag/BiOCl/AgIO 3 In the presence of AgIO 3 And BiOCl. From a partial enlarged view (fig. 2,2 θ =10-15 ° and fig. 3,2 θ =22-28 °), ag/BiOCl/AgIO was observed 3 The diffraction peak of (A) is significantly shifted compared with that of BiOCl, which indicates that AgIO 3 And BiOCl. Compared with BiOCl, ag/BiOCl/AgIO 3 The decrease in the diffraction peak intensity of the (001), (002) and (003) planes of (A) and (B) is due to the deposition of Ag and AgIO on the BiOCl (001) plane 3 The shielding effect of (1).
FIG. 4 shows Ag/BiOCl/AgIO prepared by the present invention 3 Raman spectra of heterojunction photocatalysts, wherein a and b are BiOCl and AgIO synthesized according to comparative example 1 and comparative example 2, respectively 3 And c, d, e, f, g, h are the Ranman spectra of the photocatalysts synthesized according to example 1, example 2, example 3, example 4, example 5 and example 6, respectively. BiOCl at 145cm -1 And 199cm -1 The Raman peaks correspond to A 1g Bi-Cl stretching vibration mode of (1) and (E) g The Bi-Cl stretching vibration mode of (1). AgIO 3 At-143 cm -1 The peak at (A) is due to Ag and IO 3 - 700-800 cm of the interaction between -1 The Raman peak at is derived from IO 3 - 。Ag/BiOCl/AgIO 3 Simultaneous presence of BiOCl and AgIO in photocatalyst 3 The Raman characteristic peaks of (A) indicate BiOCl and AgIO 3 Co-existing, which is consistent with XRD results. In addition, ag/BiOCl/AgIO 3 At 145cm -1 And 199cm -1 The intensity of the Raman peak is obviously lower than that of BiOCl, which is caused by simultaneously depositing Ag and AgIO on the surface of BiOCl 3 And the result is that.
In the light absorption curve of FIG. 5, a and b are BiOCl and AgIO synthesized according to comparative example 1 and comparative example 2, respectively 3 And c, d, e, f, g and h are photocatalysts synthesized according to examples 1, 2, 3, 4, 5 and 6, respectively, it being noted that BiOCl is only comparable to AgIO 3 The lower point is slightly lower, the two almost coincide when drawing, but the trends of the whole of the embodiments 1, 2, 3, 4, 5 and 6 are the same, the lines also almost coincide, but the marks are made in the subsequent enlarged insets, and the position after 800nm is almost unchanged. The light absorption curves are only for calculation of the band gaps of comparative examples 1 and 2 and illustrate that there is an SPR peak for Ag and that the light absorption of the heterojunction is higher than in comparative examples 1 and 2.BiOCl and AgIO 3 Are located in the vicinity of 372nm and 363nm, respectively, and their band gap values (BiOCl: 3.33eV 3 :3.41 eV) was obtained by the formula (1), and further the conduction band and valence band positions of BiOCl were obtained as 0.475eV,3.805eV, agIO, respectively, according to the formulas (2) and (3) 3 The positions of the conduction band and the valence band of (A) are 0.435eV and 3.845eV, respectively. Pure phase BiOCl and AgIO 3 The light absorption in the visible and near infrared regions is extremely weak, however, ag/BiOCl/AgIO 3 The light absorption in the visible and even near infrared region is significantly enhanced. A localized surface plasmon resonance peak (LSPR) for Ag was also found at about 535nm, further demonstrating Ag/BiOCl/AgIO 3 Presence of Ag in the photocatalyst. The LSPR effect of noble metals can enhance the light absorption capability of the material, thus Ag/BiOCl/AgIO 3 The enhancement of the light absorption capacity is attributed to the LSPR effect of Ag. The LSPR peak position is closely related to the size, number and shape of the noble metal. NaIO 3 As an electron acceptor, it will react with Ag + Contend for photoelectrons generated by BiOCl. Thus, naIO 3 The amount of Ag added directly affects the amount of Ag on the surface of BiOCl. Thus, different Ag/BiOCl/AgIO 3 The LSPR peak positions of the photocatalysts are also different, as shown in the inset.
In the formula:
λ — the threshold of light absorption by the photocatalyst.
E VB ＝χ-E e +0.5E g (2)
E CB ＝E VB -E g (3)
In the formula:
E VB -a value of semiconductor valence band potential;
E CB -a value of the semiconductor conduction band potential;
χ -absolute electronegativity of the semiconductor;
E e -energy level of free electrons with respect to the standard hydrogen electrode (4.5 eV);
E g -the bandgap value of the semiconductor.
FIG. 6 shows Ag/BiOCl/AgIO prepared according to example 4 of the present invention 3 XPS spectra of the heterojunction photocatalyst. The peaks at 366eV and 372eV in the figure originate from Ag + The peak at the position of-367eV and 373eV is from Ag, and the results combined with the results of fig. 1-6 prove that the prepared Ag/BiOCl/AgIO 3 BiOCl, agIO in heterojunction photocatalyst 3 Coexisting with Ag.
FIG. 7, FIG. 8, FIG. 9 and FIG. 10 show Ag/BiOCl/AgIO prepared by the present invention 3 Microstructure and morphology of the heterojunction photocatalyst. FIG. 7 shows that BiOCl is a disk-like structure (length: 1.5-6 μm, width: 1.5-3 μm, thickness: 0.3-0.6 μm) and the corresponding HRTEM image (FIG. 8) shows a clear fringe spacing of 0.276nm, indicating that the BiOCl prepared exposes the (001) crystal plane. FIG. 9 shows AgIO 3 Is an irregular lamellar structure (length: 1-6 μm, thickness: 50 nm). FIG. 10 is a schematic view ofAg/BiOCl/AgIO 3 In a heterojunction photocatalyst, agIO 3 Deposited on the (001) crystal face of BiOCl and closely contacted with BiOCl to form a heterojunction. In addition, the (001) plane of BiOCl has many small points, and the small points are Ag as can be seen by combining XPS and the ultraviolet-visible diffuse reflection curve.
FIG. 11 shows Ag/BiOCl/AgIO prepared by the present invention 3 A mechanism diagram of the formation of the heterojunction photocatalyst. Due to the strong exciton effect of BiOCl, only few electrons and few holes migrate to the (001) and (110) crystal planes of BiOCl, respectively, while a large number of excitons (e) exist - -h + ) And (4) generating (as shown in formula). When AgNO 3 And NaIO 3 After being added into the BiOCl suspension, the (001) crystal face of BiOCl has few electrons, so the few electrons are not enough to attract Ag through electrostatic action + ，Ag + Will communicate with IO 3 - Preferential generation of ions to AgIO 3 As shown in formula (5). AgIO 3 The nucleus will further attract Ag + Forming an adsorption layer to form AgIO 3 ·Ag + Colloidal particles (as described in formula (6)), agIO 3 ·Ag + Will adsorb NO in solution 3 - Forming a diffusion layer to finally generate AgIO 3 ·Ag + ·NO 3 + (as described in formula (7)). According to DLVO theory, agIO is acted by van der Waals force 3 ·Ag + The colloidal particles are attracted to the (001) crystal plane by a small amount of electrons of the BiOCl (001) crystal plane. AgIO 3 Self-assembling to form an irregular lamellar and adsorbing the irregular lamellar on the (001) crystal face of BiOCl to form 2D AgIO 3 And a 2D BiOCl binding interface; ag + Is reduced into Ag by a small amount of electrons of a (001) crystal face and is dispersed in the (001) crystal face of BiOCl. Finally, ag and AgIO 3 Simultaneously depositing on the (001) crystal face of BiOCl to form Ag/BiOCl/AgIO 3 The photocatalyst is shown as a formula (8).
BiOCl+hυ→e - few (001)BiOCl+h + few (110)BiOCl+(e - -h + ) (4)
Ag + +IO 3 - →AgIO 3 (5)
AgIO 3 +Ag + →AgIO 3 ·Ag + (6)
AgIO 3 ·Ag + +NO 3 - →AgIO 3 ·Ag + ·NO 3 - (7)
AgIO 3 ·Ag + +e - (001)BiOCl→Ag·AgIO 3 (001)BiOCl (8)
FIG. 12 shows Ag/BiOCl/AgIO prepared by the present invention 3 PL profile of the heterojunction photocatalyst. Where a is BiOCl synthesized according to comparative example 1 and c, d, e, f, g and h are photocatalysts synthesized according to examples 1, 2, 3, 4, 5 and 6, respectively. Ag/BiOCl/AgIO 3 The PL peak intensity of (A) is significantly lower than that of BiOCl, which indicates that Ag/BiOCl/AgIO 3 The separation rate of the medium charges is higher than that of BiOCl. In all Ag/BiOCl/AgIO 3 In the photocatalyst, ag/BiOCl/AgIO 3 PL Peak intensity of-4 is weakest, indicating when NaIO 3 When the amount of (2) is 0.2g, the separation rate of photogenerated carriers reaches the maximum.
FIGS. 13 and 14 are schematic views of the Ag/BiOCl/AgIO samples prepared in accordance with the present invention 3 I-t curves and EIS spectra of the heterojunction photocatalyst. Wherein a and b are BiOCl and AgIO synthesized according to comparative example 1 and comparative example 2, respectively 3 And c, d, e, f, g and h are photocatalysts synthesized according to example 1, example 2, example 3, example 4, example 5 and example 6, respectively, and fig. 13 shows that all samples have photocurrent responses under simulated sunlight, which indicates that they can generate photo-generated charges under illumination and photo-generated electrons can directionally migrate. Apparently, pure phase BiOCl and AgIO 3 The photocurrents of (a) are extremely weak, since they are all wide band gap semiconductors, responding only to uv light, which is around 6% of sunlight. Compared with a pure phase sample, ag/BiOCl/AgIO 3 The photocurrent of the photocatalyst is obviously enhanced, and Ag/BiOCl/AgIO 3 The photocurrent of-4 was 0.25 μ A, which indicates that its photocurrent separation rate and mobility were the largest. In FIG. 14, ag/BiOCl/AgIO 3 Circular arc radius ratio BiOCl and AgIO of photocatalyst 3 Is small. Further by impedance fitting, an equivalent circuit diagram (the diagram in FIG. 11) and a corresponding charge transfer resistance value (R) were obtained ct As shown in Table 1Shown). Ag/BiOCl/AgIO 3 R of-4 ct Minimum value (1.86X 10) 4 Ω)，R ct Smaller values indicate faster interfacial charge transfer and higher carrier separation rates. Therefore, according to the radius of the circular arc and R ct The value is known as Ag/BiOCl/AgIO 3 The photocatalyst is more beneficial to carrier separation, and Ag/BiOCl/AgIO 3 -4 has the greatest carrier separation ratio.
Table 1 equivalent circuit fitting results
FIG. 15 is a graph of 10mg/L rhodamine B (RhB) solution degraded by the product prepared in comparative examples 1-2 and 1-6, and FIG. 16 is a graph of 5mg/L rhodamine B (RhB) degraded by the product prepared in example 4, wherein a and B are BiOCl and AgIO synthesized in comparative examples 1 and 2, respectively 3 And c, d, e, f, g and h are photocatalysts synthesized according to example 1, example 2, example 3, example 4, example 5 and example 6, respectively. In FIG. 15, after 2h of illumination, biOCl and AgIO 3 The degradation rates for RhB were 32% and 20%, respectively, however, ag/BiOCl/AgIO 3 The degradation rate of RhB can reach 91%. Due to Ag/BiOCl/AgIO 3 The light absorption in the near infrared region is obviously higher than that of BiOCl and AgIO 3 The same degradation experiment was also performed under near infrared light waves. As shown in FIG. 16, ag/BiOCl/AgIO 3 RhB can be degraded at 850nm,940nm and 1100nm, the degradation rates are 86%, 84% and 82%, respectively, which indicates that Ag/BiOCl/AgIO 3 Solar energy can be utilized more efficiently.
In the active species trapping experiment of FIG. 15, p-benzoquinone (pBQ), disodium ethylenediaminetetraacetate (EDTA-2 Na), and t-butanol (tBuOH) were introduced as. O 2 - ，h + And OH trapping agent plays a role in inhibiting photodegradation reaction to different degrees. From the capture result, O 2 - And h + Is the primary active species, while. OH is the secondary active species. Previously calculated from the light absorption curvesBiOCl and AgIO 3 Has a conductivity of 0.475V and 0.435V, respectively, which is lower than O 2 /·O 2 - Potential (-0.046V). In this case, it is impossible to generate O 2 - This contradicts experimental facts. Therefore, there must be another mechanism to raise the conduction band potential of the semiconductor, resulting in the generation of O 2 - . Next, biOCl and AgIO were calculated 3 Work function (W) of F ). The work functions of Ag and BiOCl were 4.23eV and 7.37eV, respectively (see fig. 17 and 18). According to the formula of work function, the larger the work function is, the Fermi level (E) is shown F ) The lower. When Ag and BiOCl come into contact with each other, an interface is formed, and in order to balance the fermi level, electrons flow from the end having a high fermi level to the end having a low fermi level, that is, electrons in Ag flow to BiOCl (this process is shown by arrows in fig. 20). The work function of Ag-BiOCl was 4.86eV (as in FIG. 19) lower than that of BiOCl (7.37 eV), indicating that Ag can raise the Fermi level of BiOCl. This is due to the fact that the electron concentration itself in Ag is high, the electron flow has little effect on its fermi level, but is mainly a rise in the BiOCl fermi level (see fig. 20). Finally, the photodegradation stage can generate O 2 - 。
FIG. 21 shows Ag/BiOCl/AgIO prepared by the present invention 3 A photocatalytic mechanism diagram of a heterojunction photocatalyst. Based on the above theoretical calculation results, the fermi level of BiOCl is raised by 2.51eV, and the new fermi level is shown as the thick dotted line on the right side of the figure. In this case, the conduction band potential and the valence band potential of BiOCl were-2.035V and 1.295V, respectively, and BiOCl and AgIO 3 Has an embedded structure. Under illumination, biOCl and AgIO 3 The valence band electrons are excited into the conduction band leaving a corresponding hole in the valence band. If AgIO 3 The valence band hole migrates to the valence band of BiOCl, which then does not correspond to the active species result (in which case OH is the predominant active species). Thus, biOCl and AgIO 3 A direct Z-shaped heterojunction is inevitably formed between the two layers, and direct Z-shaped Ag/BiOCl/AgIO is generated 3 A photocatalyst. AgIO 3 Electrons of the conduction band recombine with holes of the BiOCl valence band, leaving electrons of the BiOCl conduction band and AgIO 3 The holes of the valence band participate in the redox reaction. Due to the fact thatThe strong exciton effect of BiOCl generates only a few electrons, and generates a large number of primary excitons (as shown in the lower right ellipse). Under illumination, high-energy electrons generated by Ag contribute to near-infrared degradation, however, free electrons in Ag do high-speed motion around a nucleus, and the energy of the free electrons is higher than that of electrons in primary excitons. Therefore, the free electrons in Ag compete for the holes in the primary excitons to generate secondary excitons (the process is shown by the lower left arrow), while the electrons in the primary excitons are released into the conduction band of BiOCl to participate in the reduction reaction (the process is shown by the upper right arrow). Under the action of Ag and direct Z-type heterojunction, exciton dissociation and carrier separation are accelerated, and Ag/BiOCl/AgIO is endowed 3 High photocatalytic activity. Simulating Ag/BiOCl/AgIO in sunlight 3 The degradation rates of RhB are BiOCl and AgIO respectively 3 2.8 and 6.4 times of that of the compound and can effectively degrade RhB under near infrared light.
The above description is only one embodiment of the present invention, and not all or only one embodiment, and any equivalent modifications of the technical solutions of the present invention, which are made by a person skilled in the art through reading the present specification, are all covered by the claims of the present invention.
Claims (5)
1. Ag/BiOCl/AgIO 3 A method for preparing a heterojunction photocatalyst is characterized by comprising the following steps,
step 1, adding deionized water into BiOCl powder with exposed (001) crystal face, stirring at room temperature for 30-40 min to obtain suspension, and adding AgNO 3 Powder and NaIO 3 Powder, biOCl powder, agNO 3 Powder and NaIO 3 The mass ratio of the powder is 0.3: (0.01-0.05): (0.05-0.3), and uniformly mixing to obtain a mixed system;
step 2, performing illumination reaction on the mixed system for 2-3 hours under a light source to obtain a reaction solution;
step 3, separating and drying the product in the reaction solution to obtain Ag/BiOCl/AgIO 3 A heterojunction photocatalyst.
2. The Ag/BiOCl/AgIO of claim 1 3 The preparation method of the heterojunction photocatalyst is characterized in that BiOCl powder and AgNO in the step 1 3 Powder and NaIO 3 The concentration of the powder in the mixed system is expressed in g/mL, and the proportion is (5.00-7.50): (0.17-1.25): (0.83-7.50).
3. Ag/BiOCl/AgIO according to claim 1 3 The preparation method of the heterojunction photocatalyst is characterized in that in the step 2, the mixed system reacts in a photochemical reactor.
4. A Ag/BiOCl/AgIO material according to any one of claims 1 to 3 3 Ag/BiOCl/AgIO obtained by preparation method of heterojunction photocatalyst 3 A heterojunction photocatalyst, the Ag/BiOCl/AgIO 3 The heterojunction photocatalyst is direct Z-type heterojunction photocatalyst, wherein Ag and AgIO 3 Are deposited on the (001) crystal face of BiOCl.
5. The Ag/BiOCl/AgIO of claim 4 3 Application of the heterojunction photocatalyst in degrading rhodamine B under sunlight and near infrared light.
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| CN105709782A (en) * | 2016-03-09 | 2016-06-29 | 安徽工业大学 | Preparing method and application of Ag/AgBr/BiOCl-(001) nanometer composite material |
| CN108772077A (en) * | 2018-06-26 | 2018-11-09 | 福建工程学院 | A kind of AgIO3/Ag2O heterojunction photocatalysis materials and its preparation method and application |
| PH22018050418Y1 (en) * | 2018-09-28 | 2019-06-26 | Univ Philippines Visayas | Process of preparing nitrogen doped bismuth oxide-bismuth oxychloride photocatalyst |
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| The enhanced photocatalytic activity of Ag-OVs-(001) BiOCl by separating secondary excitons under double SPR effects;Dan Zhang et al.;《Applied Surface Science》;20200516;第526卷;摘要、第2页右栏倒数第1段、第3页左栏第1段、第5页右栏倒数第1段 * |
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