CN112973670A - Preparation method of bismuth molybdate material for removing NO through photocatalysis and product - Google Patents

Preparation method of bismuth molybdate material for removing NO through photocatalysis and product Download PDF

Info

Publication number
CN112973670A
CN112973670A CN202110180440.XA CN202110180440A CN112973670A CN 112973670 A CN112973670 A CN 112973670A CN 202110180440 A CN202110180440 A CN 202110180440A CN 112973670 A CN112973670 A CN 112973670A
Authority
CN
China
Prior art keywords
bismuth molybdate
solution
photocatalysis
deionized water
precursor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202110180440.XA
Other languages
Chinese (zh)
Inventor
汪佩
江小龙
汪圣尧
杨懿
陈浩
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huazhong Agricultural University
Original Assignee
Huazhong Agricultural University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huazhong Agricultural University filed Critical Huazhong Agricultural University
Priority to CN202110180440.XA priority Critical patent/CN112973670A/en
Publication of CN112973670A publication Critical patent/CN112973670A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/24—Chromium, molybdenum or tungsten
    • B01J23/31—Chromium, molybdenum or tungsten combined with bismuth
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86—Catalytic processes
    • B01D53/8621—Removing nitrogen compounds
    • B01D53/8625—Nitrogen oxides
    • B01D53/8628—Processes characterised by a specific catalyst
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G39/00—Compounds of molybdenum
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/80—Type of catalytic reaction
    • B01D2255/802—Photocatalytic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/40—Nitrogen compounds
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
    • C01P2002/86—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by NMR- or ESR-data

Abstract

The invention discloses a preparation method of a bismuth molybdate material for removing NO by photocatalysis, belonging to the field of removing NO by photocatalysis, and the preparation method comprises the following steps: (1) mixing Na2MoO4·2H2O and Bi (NO)3)3·5H2O is respectively added into deionized water to be dissolved; (2) transferring the solution prepared in the step (1) into a reaction kettle, heating the solution in an oven, and naturally cooling the solution after the reaction is finished; (3) centrifuging the sample prepared in the step (2) to obtain a precipitate, and then washing and drying to obtain a bismuth molybdate precursor; (4) dispersing the precursor obtained in the step (3) into deionized water, and then adding an alkaline solution for stirring treatment; (5) washing the solution in the step (4) for a plurality of times, and drying in an oven, and finallyFinally obtaining the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis. By controlling the amount of the alkaline solution, the prepared bismuth molybdate catalyst has high-efficiency capability of removing NO by photocatalysis and is toxic to by-product NO2The yield is low.

Description

Preparation method of bismuth molybdate material for removing NO through photocatalysis and product
Technical Field
The invention belongs to the technical field of catalyst preparation, and particularly relates to a preparation method of a bismuth molybdate material for removing nitric oxide through photocatalysis and a product.
Background
Nitrogen Oxides (NO) in air influenced by fossil fuel combustion, mineral combustion and large amount of automobile exhaustx) The pollution problem is increasingly severe, which not only causes respiratory diseases of human bodies to impair health, but also is one of the crimes of environmental problems such as acid rain, haze, ozone cavities, photochemical smog and the like. Nitric Oxide (NO) is NOxAbout 90% of the total amount of the components. At present, the NO removal method mainly comprises an adsorption method, a microbiological method, a thermal catalysis method and the like. The equipment involved in the methods has high running cost and large energy consumption, is generally used for treating high-concentration automobile exhaust and industrial waste gas, but has poor removal effect on low-concentration (ppm order) NO, and has the risks of high energy consumption and secondary pollution. The photocatalysis technology draws wide attention due to the advantages of environmental protection, mild reaction conditions, low energy consumption and the like. Research has found that photocatalytic technology is one of the effective methods for effectively removing low-concentration NO.
The photocatalytic removal of NO is by catalytic oxidation of NO to NO3 -Realized that toxic and harmful intermediate product NO is easily generated in the process2To achieve efficient NO removal while suppressing NO2The selection of the photocatalyst is most critical to the formation. The bismuth molybdate system has the characteristics of stable chemical property, strong light absorption and environmental friendliness, can be used for decomposing water to produce hydrogen by visible light catalysis after the first report in 2005, is introduced to solve the problem of environmental pollution, such as phenol degradation by photocatalysis, pentachlorophenol degradation, NO removal and the like, and is a photocatalyst with application potential. However, the bismuth molybdate material synthesized by the traditional method is due toThe disadvantages of low separation efficiency of photon-generated carriers and low quantum yield limit the industrial application of the photon-generated carriers.
Therefore, it is required to develop a novel preparation method of bismuth molybdate catalyst for removing nitric oxide by photocatalysis, which overcomes the disadvantages of low separation efficiency of photo-generated carriers and low quantum yield.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a preparation method of a bismuth molybdate material for removing nitric oxide by photocatalysis and a product, wherein the defect is introduced by etching the bismuth molybdate material by alkali, so that the efficiency of removing NO by photocatalysis is improved, and NO is reduced2The preparation method has simple process, easy industrialization and low cost.
In order to achieve the above object, the present invention provides a method for preparing a bismuth molybdate material for photocatalytic removal of NO, comprising the steps of:
s1: the preparation of the bismuth molybdate precursor is carried out,
s2: dispersing a bismuth molybdate precursor into deionized water, adding an alkali solution, stirring to perform alkali etching on the bismuth molybdate precursor, and performing alkali etching on MoO in the bismuth molybdate6Defects are introduced by the etching action of the octahedron to obtain the defect-containing bismuth molybdate catalyst, the temperature for carrying out alkali etching is 80-120 ℃, the pH value of the alkali solution is 9-13,
s3: and (4) washing the solution obtained in the step S2, and then drying to obtain the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis.
Further, the aqueous alkali is ammonia water, the mass percent of the ammonia water is 25% -28%, and the pH value is 9.3-11.
Furthermore, the temperature of the ammonia water for etching is 80 ℃, and the pH value is 9.3-10.2.
Further, the adding amount of the ammonia water and the bismuth molybdate precursor solution satisfy the following relationship: 0.1ml to 10ml of ammonia water with the mass percentage of 25 percent to 28 percent is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution in which 0.2g of bismuth molybdate precursor is dissolved in 50ml of deionized water.
Furthermore, 5ml to 7ml of ammonia water with a mass percentage of 25% to 28% is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution in which 0.2g of the bismuth molybdate precursor is dissolved in 50ml of deionized water.
Further, in step S1, the specific steps of preparing the bismuth molybdate precursor are as follows:
s11: mixing Na2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, and stirring uniformly to obtain a white suspension;
s12: transferring the solution prepared in the step S11 into a reaction kettle with polytetrafluoroethylene, placing the reaction kettle into a drying oven at 160 ℃ for heating for 24 hours, and naturally cooling after the reaction is finished;
s13: and centrifuging the sample prepared in the step S12 to obtain a precipitate, washing the precipitate with ethanol and deionized water respectively for at least two times, and drying the precipitate in an oven at 60 ℃ for at least 10 hours to obtain the bismuth molybdate precursor.
Further, in step S3, the solution obtained in step S2 is washed with deionized water at least five times, and dried overnight (at least 10h) in an oven at 60 ℃ to obtain the high-performance bismuth molybdate catalytic material for photocatalytic removal of NO.
Further, in step S11, Na is added2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, stirring to obtain white suspension, mixing, and adding Na2MoO4·2H2O and Bi (NO)3)3·5H2The concentrations of O are 0.05mol/L and 0.1mol/L respectively, Na2MoO4·2H2Mo element of O and Bi (NO)3)3·5H2The molar ratio of the Bi element of O is 1: 2.
Further, in step S2, the bismuth molybdate precursor is dispersed in deionized water, and an alkali solution is added for magnetic stirring.
According to a second aspect of the present invention, there is also provided a bismuth molybdate material prepared as described above, which has a removal rate of NO removal by photocatalysis of more than 33%.
The bismuth molybdate material prepared by the method is rich in defects, and particularly, MoO in bismuth molybdate is treated by alkali6The octahedral etching introduces defects, oxygen defects and simultaneous exposure of coordinatively unsaturated Mo atoms. Oxygen defects and coordination unsaturated Mo can serve as a capture site of photo-generated electrons, so that carrier recombination is reduced, and separation of the photo-generated carriers is facilitated; meanwhile, oxygen defects and unsaturated Mo can be used as active sites to activate gas molecules, so that the removal efficiency of photocatalytic NO is improved.
Generally, compared with the prior art, the above technical solution conceived by the present invention has the following beneficial effects:
the defect-containing bismuth molybdate material is prepared by a simple and feasible hydrothermal method and an alkali etching method, and when the defect-containing bismuth molybdate material is used for removing photocatalytic NO, the defect-containing bismuth molybdate material has high light utilization rate, high reaction activity (meaning that the NO removal rate is high) and high selectivity (meaning that a byproduct NO is high)2Low generation), specifically, the NO removal rate is up to 47%, and the by-product NO is2The amount of the formed product is as low as 46ppb (1ppb is 0.001 ppm). In addition, the invention has low cost, simple process and strong controllability, and is beneficial to market popularization.
Drawings
FIG. 1 shows the results of the activities of the bismuth molybdate materials of examples 1,2,3 and 4 of the present invention and comparative example 1 for removing NO by light, wherein CtDenotes the NO concentration in the gas flow at t min of light irradiation, C0To achieve NO concentration at adsorption equilibrium.
FIG. 2 is a graph showing NO in experiments of removing NO by light using bismuth molybdate materials according to examples 1,2,3 and 4 of the present invention and comparative example 12Yield the results of the quantities.
FIG. 3 shows the results of electron spin resonance spectroscopy (ESR) in example 1 of the present invention.
FIG. 4 shows the result of electron spin resonance spectroscopy (ESR) in example 2 of the present invention.
FIG. 5 shows the result of electron spin resonance spectroscopy (ESR) in example 3 of the present invention.
FIG. 6 shows the result of electron spin resonance spectroscopy (ESR) in example 4 of the present invention.
FIG. 7 shows the results of an electron spin resonance spectrum (ESR) of comparative example 1 of the present invention.
As can be seen by comparing the results of fig. 3 to 7, a significant increase in spin signal intensity occurred after ammonia treatment compared to before ammonia treatment, indicating the introduction of defects in the material.
The first table shows the evaluation results of the performance of the catalysts prepared in examples 1 to 4 and comparative examples in removing NO by light.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The catalytic activity can be greatly improved by introducing defects into the catalyst, on one hand, the defects can be used as active sites for activating reactants, and on the other hand, the defects can be used as electron capture traps to capture photo-generated electrons so as to reduce the recombination of photo-generated carriers. The introduction of oxygen vacancies in the bismuth molybdate system can obviously improve the performance of the bismuth molybdate system in removing NO by photocatalysis. The defect-containing bismuth molybdate catalyst is obtained by alkali (ammonia water) treatment, and MoO in the bismuth molybdate is treated by alkali6Defects are introduced by the etching effect of the octahedron, so that the defective bismuth molybdate material for removing NO by high-performance photocatalysis is constructed.
The invention provides a preparation method of a bismuth molybdate material for removing NO by photocatalysis, which comprises the following steps:
s1: preparing a bismuth molybdate precursor, wherein the specific steps for preparing the bismuth molybdate precursor are as follows:
s11: mixing Na2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, stirring to obtain white suspension, mixing, and adding Na2MoO4·2H2O and Bi (NO)3)3·5H2The concentrations of O are 0.05mol/L and 0.1mol/L respectively, Na2MoO4·2H2Mo element of O and Bi (NO)3)3·5H2The molar ratio of the Bi element of O is 1: 2.
S12: transferring the solution prepared in the step S11 into a reaction kettle with polytetrafluoroethylene, placing the reaction kettle into a drying oven at 160 ℃ for heating for 24 hours, and naturally cooling after the reaction is finished;
s13: and centrifuging the sample prepared in the step S12 to obtain a precipitate, washing the precipitate with ethanol and deionized water respectively for at least two times, and drying the precipitate in an oven at 60 ℃ for at least 12 hours to obtain the bismuth molybdate precursor.
S2: dispersing a bismuth molybdate precursor into deionized water, adding an alkali solution for magnetic stirring to perform alkali etching on the bismuth molybdate precursor, and performing alkali etching on MoO in the bismuth molybdate6And introducing defects under the etching action of the octahedron to obtain the defect-containing bismuth molybdate catalyst, wherein the temperature for performing alkali etching is 80-120 ℃, and the pH value of the alkali solution is 9-13. Preferably, the aqueous alkali is ammonia water, the mass percent of the ammonia water is 25% -28%, and the pH value is 9.3-11. Further preferably, the temperature for etching by ammonia is 80 ℃, and the pH value is 9.3-10.2. The adding amount of the ammonia water and the bismuth molybdate precursor solution satisfy the following relationship: 0.1ml to 10ml of ammonia water with the mass percentage of 25 percent to 28 percent is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution in which 0.2g of bismuth molybdate precursor is dissolved in 50ml of deionized water. Furthermore, 5ml to 7ml of ammonia water with a mass percentage of 25% to 28% is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution in which 0.2g of the bismuth molybdate precursor is dissolved in 50ml of deionized water.
S3: and (4) washing the solution obtained in the step S2, and then drying to obtain the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis. Specifically, the solution obtained in step S2 is washed with deionized water at least five times, and dried in an oven at 60 ℃ for 10 to 12 hours to obtain the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis.
The bismuth molybdate material is used as a catalyst for removing NO by photocatalysis (full spectrum), and the removal rate of NO by photocatalysis is more than 33%.
Example 1:
the preparation method of the defective bismuth molybdate-containing material (BMO-OH) comprises the following steps:
(1) adding 2.5mmol of Na2MoO4·2H2O in 30ml of deionized water, 5mmol of Bi (NO)3)3·5H2Dissolving O in 20ml of deionized water, and uniformly mixing and stirring to obtain a white suspension;
(2) transferring the solution prepared in the step (1) into a reaction kettle with polytetrafluoroethylene, placing the reaction kettle into a drying oven at 160 ℃, heating for 24 hours, and naturally cooling after the reaction is finished;
(3) centrifuging the sample prepared in the step (2) to obtain a precipitate, washing the precipitate with ethanol and deionized water respectively for 3 times, and drying the precipitate in an oven at 60 ℃ overnight (for at least 10 hours) to obtain a bismuth molybdate precursor;
(4) 0.2g of the bismuth molybdate obtained in (3) was weighed and dispersed in 50mL of deionized water, and then 5mL of aqueous ammonia was added, and magnetic stirring was carried out at 80 ℃ for 2 hours, the pH value of the aqueous ammonia being 10.2.
(5) Washing the solution in the step (4) with deionized water for 10 times, and drying in an oven at 60 ℃ overnight (at least 10h) to obtain the defect-containing bismuth molybdate catalytic material (marked as BMO-OH)
The applications of the photocatalytic material containing defects prepared in this example are as follows: 50mg of the catalyst was dispersed with 16mL of water by sonication, and the mixture was poured onto a clean glass petri dish (diameter: 12cm), and the dish was left to stand in an oven at 60 ℃ for 10 hours to dry. Experiments with photocatalytic removal of NO were performed at ambient temperature in a continuous flow reactor. In a rectangular reactor made of stainless steel and covered with a quartz glass window having a volume of 4.5L (30 cm. times.15 cm. times.10 cm), a petri dish loaded with a sample was placed in the reactor. An LED lamp was placed as a light source (power 30W) on a quartz glass window directly above the petri dish. Full spectrum photocatalytic NO removal experiments were performed at ambient temperature. Wherein, NO gas is provided by a compressed gas cylinder, the concentration of NO in the gas cylinder is 120ppm (Ar balance), and then the NO gas is mixed with air delivered by an air compressor (BCHP-A10), and the process controls the flow of the two gases by a flow controller (NO is 4.2ml/min, and air is 1L/min). The NOx concentration in the gas stream was continuously measured using a model T200 NOx analyzer (Teledyne API). After the adsorption-desorption equilibrium was reached (NO concentration about 600ppb), L was turned onAn ED lamp. The NOx analyzer can automatically read NO and NO in the air flow every 1min in the illumination process for 45min2Concentration, after opening for 15min, the NO removal rate is up to 47%, and NO is removed at this time2The amount produced was only 46ppb (see fig. 1, fig. 2 and table one).
The above tests show that defects can be formed in the bismuth molybdate material by means of alkali etching (fig. 3). The material containing defective bismuth molybdate has excellent NO removal performance by photocatalysis, and NO2The generated amount is low, and the material is a potential material which can be used for removing low-concentration NO by photocatalysis.
Example 2:
example 2 the catalyst was prepared as in example 1, except that: in the step 4), the dosage of ammonia water is 0.1mL, and the pH value of the ammonia water is 9.3. Its photocatalytic removal of NO efficiency and NO2The results of the amounts produced are shown in table 1, and fig. 1 and 2. The label of this example is BMO-OH (0.1 ml).
Example 3:
example 3 the catalyst was prepared as in example 1, except that: in the step 4), the dosage of ammonia water is 1mL, and the pH value of the ammonia water is 9.8. Its photocatalytic removal of NO efficiency and NO2The results of the amounts produced are shown in table 1, and fig. 1 and 2. The label of this example is BMO-OH (1 ml).
Example 4:
example 4 the catalyst was prepared as in example 1, except that: the dosage of ammonia water in the step 4) is 10mL, and the pH value of the ammonia water is 10.3. Its photocatalytic removal of NO efficiency and NO2The results of the amounts produced are shown in table 1, and fig. 1 and 2. The label of this example is BMO-OH (10 ml).
Comparative example 1:
comparative example 1 the catalyst was prepared as in example 1, except that: the comparative example should be the preparation of the bismuth molybdate precursor obtained in step 3 without subsequent ammonia treatment. The catalyst is labeled BMO, which photocatalytically removes NO efficiency and NO2The results of the amounts produced are shown in table 1, and fig. 1 and 2.
Wherein, FIG. 1 shows bismuth molybdate materials of examples 1,2,3 and 4 of the present invention and comparative example 1The material light removes the activity result of NO, wherein, CtDenotes the NO concentration in the gas flow at t min of light irradiation, C0To achieve NO concentration at adsorption equilibrium. FIG. 2 is a graph showing NO in experiments of removing NO by light using bismuth molybdate materials according to examples 1,2,3 and 4 of the present invention and comparative example 12Yield the results of the quantities. The comparison shows that: the NO content is obviously reduced when the light is irradiated for 15min, which shows that the reaction activity is high. Compared with the examples 1,2,3 and 4 after the alkali etching in the comparative example 1, the photocatalytic NO removal rate is improved, wherein the activity of the example 1 is improved most, the NO removal rate is improved to 47% from 22% in the comparative example 1, the removal rate is improved by about two times, and meanwhile, toxic by-product NO is generated2The content of (B) was also reduced from 55ppb of comparative example 1 to 46ppb at 15min
Fig. 3 is a result of an electron spin resonance spectrum (ESR) of example 1 of the present invention, fig. 4 is a result of an electron spin resonance spectrum (ESR) of example 2 of the present invention, fig. 5 is a result of an electron spin resonance spectrum (ESR) of example 3 of the present invention, fig. 6 is a result of an electron spin resonance spectrum (ESR) of example 4 of the present invention, and fig. 7 is a result of an electron spin resonance spectrum (ESR) of comparative example 1 of the present invention, and it can be seen from a comparison of the above figures that a defect-free signal appears before ammonia treatment, a defect signal remarkably increases after ammonia treatment, and an oxygen defect appears in a material whose surface has been treated with ammonia.
Watch 1
Experimental group Catalyst and process for preparing same NO removal Rate (%) Amount of NO2 produced (ppb)
Comparative example 1 BMO 22 55
Example 1 BMO-OH 47 46
Example 2 BMO-OH(0.1ml) 37 110
Example 3 BMO-OH(1ml) 43 67
Example 4 BMO-OH(10ml) 36 54
Table 1 shows the results of evaluating the NO removing performance of the catalysts prepared in examples 1 to 4 and comparative examples, and it can be seen that the NO removing rate of comparative example 1, i.e. the sample before alkali etching, after 15min of light irradiation is only 22%, NO is generated at this time255 ppb. The defective samples after alkali etching in examples 1 to 4 have obviously improved NO removal rate, but NO is removed2The amount of production varies under different alkaline etching conditions, wherein, under optimal alkaline etching conditions (i.e. 5ml of ammonia), NO2Is only 46ppb lower than NO in comparative example 12The generated amount shows that the reaction activity and the selectivity of the catalyst for removing NO by photocatalysis are improved.
Example 5:
s1: preparing a bismuth molybdate precursor, wherein the specific steps for preparing the bismuth molybdate precursor are as follows:
s11: mixing Na2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, stirring to obtain white suspension, mixing, and adding Na2MoO4·2H2O and Bi (NO)3)3·5H2The concentrations of O are 0.05mol/L and 0.1mol/L respectively, Na2MoO4·2H2Mo element of O and Bi (NO)3)3·5H2The molar ratio of the Bi element of O is 1: 2.
S12: transferring the solution prepared in the step S11 into a reaction kettle with polytetrafluoroethylene, placing the reaction kettle into a drying oven at 160 ℃ for heating for 24 hours, and naturally cooling after the reaction is finished;
s13: and centrifuging the sample prepared in the step S12 to obtain a precipitate, washing the precipitate with ethanol and deionized water respectively for at least two times, and drying the precipitate in an oven at 60 ℃ for at least 10 hours to obtain the bismuth molybdate precursor.
S2: dispersing a bismuth molybdate precursor into deionized water, adding an alkali solution for magnetic stirring to perform alkali etching on the bismuth molybdate precursor, and performing alkali etching on MoO in the bismuth molybdate6Defects are introduced by the etching action of octahedron to obtain the defect-containing bismuth molybdate catalyst, and the temperature for carrying out alkali etching is 80 ℃. Preferably, the alkali solution is ammonia water, and the mass percent of the ammonia water is 28%. The pH of ammonia is 10.2, and the mixture is stirred for 4 hours by magnetic force. The adding amount of the ammonia water and the bismuth molybdate precursor solution satisfy the following relationship: 5ml of ammonia water is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution obtained by dissolving 0.2g of bismuth molybdate precursor in 50ml of deionized water.
S3: and (4) washing the solution obtained in the step S2, and then drying to obtain the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis. Specifically, the solution obtained in step S2 is washed with deionized water at least five times, and dried in an oven at 60 ℃ for at least 10 hours to obtain the high-performance bismuth molybdate catalytic material for photocatalytic removal of NO.
The bismuth molybdate material of the invention is used as a photo (full spectrum) catalytic NO removalThe removal rate of NO by photocatalysis is about 38 percent by using the removal catalyst, and NO is2The amount produced was 60 ppb.
Example 6:
s1: preparing a bismuth molybdate precursor, wherein the specific steps for preparing the bismuth molybdate precursor are as follows:
s11: mixing Na2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, stirring to obtain white suspension, mixing, and adding Na2MoO4·2H2O and Bi (NO)3)3·5H2The concentrations of O are 0.05mol/L and 0.1mol/L respectively, Na2MoO4·2H2Mo element of O and Bi (NO)3)3·5H2The molar ratio of the Bi element of O is 1: 2.
S12: transferring the solution prepared in the step S11 into a reaction kettle with polytetrafluoroethylene, placing the reaction kettle into a drying oven at 160 ℃ for heating for 24 hours, and naturally cooling after the reaction is finished;
s13: and centrifuging the sample prepared in the step S12 to obtain a precipitate, washing the precipitate with ethanol and deionized water respectively for at least two times, and drying the precipitate in an oven at 60 ℃ for at least 10 hours to obtain the bismuth molybdate precursor.
S2: dispersing a bismuth molybdate precursor into deionized water, adding an alkali solution for magnetic stirring to perform alkali etching on the bismuth molybdate precursor, and performing alkali etching on MoO in the bismuth molybdate6Defects are introduced by the etching action of octahedron to obtain the defect-containing bismuth molybdate catalyst, and the pH of the alkaline solution is 9.8. Preferably, the alkali solution is ammonia water, and the mass percent of the ammonia water is 26%. Still more preferably, the temperature at which ammonia is etched is 120 ℃. The adding amount of the ammonia water and the bismuth molybdate precursor solution satisfy the following relationship: 1ml of ammonia water is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution obtained by dissolving 0.2g of bismuth molybdate precursor in 50ml of deionized water.
S3: and (4) washing the solution obtained in the step S2, and then drying to obtain the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis. Specifically, the solution obtained in step S2 is washed with deionized water at least five times, and dried in an oven at 60 ℃ for at least 10 hours to obtain the high-performance bismuth molybdate catalytic material for photocatalytic removal of NO.
The bismuth molybdate material is used as a photocatalyst for removing NO, the removal rate of NO removed by photocatalysis is about 33 percent, and NO is removed by photocatalysis2The amount produced was 84 ppb.
Example 7:
s1: preparing a bismuth molybdate precursor, wherein the specific steps for preparing the bismuth molybdate precursor are as follows:
s11: mixing Na2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, stirring to obtain white suspension, mixing, and adding Na2MoO4·2H2O and Bi (NO)3)3·5H2The concentrations of O are 0.05mol/L and 0.1mol/L respectively, Na2MoO4·2H2Mo element of O and Bi (NO)3)3·5H2The molar ratio of the Bi element of O is 1: 2.
S12: transferring the solution prepared in the step S11 into a reaction kettle with polytetrafluoroethylene, placing the reaction kettle into a drying oven at 160 ℃ for heating for 24 hours, and naturally cooling after the reaction is finished;
s13: and centrifuging the sample prepared in the step S12 to obtain a precipitate, washing the precipitate with ethanol and deionized water respectively for at least two times, and drying the precipitate in an oven at 60 ℃ for at least 10 hours to obtain the bismuth molybdate precursor.
S2: dispersing a bismuth molybdate precursor into deionized water, adding an alkali solution for magnetic stirring to perform alkali etching on the bismuth molybdate precursor, and performing alkali etching on MoO in the bismuth molybdate6The defect is introduced by the etching action of the octahedron, so that the defect-containing bismuth molybdate catalyst is obtained, the temperature for carrying out alkali etching is room temperature, and the pH value of alkali is 12.7. Preferably, the base is an analytically pure NaOH solid and is magnetically stirred for 24 h. The addition amount of the alkali and the bismuth molybdate precursor solution satisfy the following relationship: the 0.1g of NaOH is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution prepared by dissolving 0.2g of bismuth molybdate precursor in 50ml of deionized water.
S3: and (4) washing the solution obtained in the step S2, and then drying to obtain the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis. Specifically, the solution obtained in step S2 is washed with deionized water at least five times, and dried in an oven at 60 ℃ for at least 10 hours to obtain the high-performance bismuth molybdate catalytic material for photocatalytic removal of NO.
The bismuth molybdate material is used as a photocatalyst for removing NO, the removal rate of NO removed by photocatalysis is about 48 percent, and NO is removed by photocatalysis2The amount produced was 73 ppb.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims (10)

1. A preparation method of a bismuth molybdate material for removing NO by photocatalysis is characterized by comprising the following steps:
s1: the preparation of the bismuth molybdate precursor is carried out,
s2: dispersing a bismuth molybdate precursor into deionized water, adding an alkali solution, stirring to perform alkali etching on the bismuth molybdate precursor, and performing alkali etching on MoO in the bismuth molybdate6Defects are introduced by the etching action of the octahedron to obtain the defect-containing bismuth molybdate catalyst, the pH value of the alkali solution is 9-13,
s3: and (4) washing the solution obtained in the step S2, and then drying to obtain the high-performance bismuth molybdate catalytic material for removing NO by photocatalysis.
2. The method for preparing the bismuth molybdate material for removing NO through photocatalysis as claimed in claim 1, wherein the alkali solution is ammonia water, the mass percent of the ammonia water is 25-28%, and the pH is 9.3-11.
3. The method for preparing the bismuth molybdate material for removing NO through photocatalysis as claimed in claim 2, wherein the temperature for etching by ammonia water is 80 ℃, and the pH value is 9.3-10.2.
4. The method for preparing the bismuth molybdate material for removing NO through photocatalysis as claimed in claim 3, wherein the adding amount of the ammonia water and the bismuth molybdate precursor solution satisfy the following relationship:
0.1ml to 10ml of ammonia water with the mass percentage of 25 percent to 28 percent is correspondingly used for etching the bismuth molybdate precursor solution with the set concentration, and the bismuth molybdate precursor solution with the set concentration is a solution in which 0.2g of bismuth molybdate precursor is dissolved in 50ml of deionized water.
5. The method for preparing the bismuth molybdate material for removing NO through photocatalysis as claimed in claim 4, wherein 5ml to 7ml of ammonia water with a mass percentage of 25 percent to 28 percent is correspondingly used for etching the bismuth molybdate precursor solution with a set concentration, and the bismuth molybdate precursor solution with a set concentration is a solution of 0.2g of bismuth molybdate precursor dissolved in 50ml of deionized water.
6. The method for preparing the bismuth molybdate material for photocatalytic removal of NO as claimed in claim 5, wherein in step S1, the specific steps for preparing the bismuth molybdate precursor are as follows:
s11: mixing Na2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, and stirring uniformly to obtain a white suspension;
s12: transferring the solution prepared in the step S11 into a reaction kettle with polytetrafluoroethylene, placing the reaction kettle into a drying oven at 160 ℃ for heating for 24 hours, and naturally cooling after the reaction is finished;
s13: and centrifuging the sample prepared in the step S12 to obtain a precipitate, washing the precipitate with ethanol and deionized water respectively for at least two times, and drying the precipitate in an oven at 60 ℃ for at least 10 hours to obtain the bismuth molybdate precursor.
7. The method of claim 6, wherein in step S3, the solution obtained in step S2 is washed with deionized water at least five times, and dried in an oven at 60 ℃ overnight to obtain the high-performance bismuth molybdate catalytic material for photocatalytic NO removal.
8. The method of claim 7, wherein in step S11, Na is added2MoO4·2H2O and Bi (NO)3)3·5H2Adding O into deionized water respectively, stirring to obtain white suspension, mixing, and adding Na2MoO4·2H2O and Bi (NO)3)3·5H2The concentrations of O are 0.05mol/L and 0.1mol/L respectively, Na2MoO4·2H2Mo element of O and Bi (NO)3)3·5H2The molar ratio of the Bi element of O is 1: 2.
9. The method of claim 8, wherein in step S2, the bismuth molybdate precursor is dispersed in deionized water, and an alkaline solution is added for magnetic stirring.
10. The bismuth molybdate material prepared according to the method of any one of claims 1 to 9, wherein the removal rate of NO by photocatalysis is greater than 33%.
CN202110180440.XA 2021-02-09 2021-02-09 Preparation method of bismuth molybdate material for removing NO through photocatalysis and product Pending CN112973670A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110180440.XA CN112973670A (en) 2021-02-09 2021-02-09 Preparation method of bismuth molybdate material for removing NO through photocatalysis and product

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110180440.XA CN112973670A (en) 2021-02-09 2021-02-09 Preparation method of bismuth molybdate material for removing NO through photocatalysis and product

Publications (1)

Publication Number Publication Date
CN112973670A true CN112973670A (en) 2021-06-18

Family

ID=76392894

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110180440.XA Pending CN112973670A (en) 2021-02-09 2021-02-09 Preparation method of bismuth molybdate material for removing NO through photocatalysis and product

Country Status (1)

Country Link
CN (1) CN112973670A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114700067A (en) * 2022-04-20 2022-07-05 重庆文理学院 Oxygen-rich vacancy bismuth molybdate photocatalytic material and preparation method and application thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001051202A1 (en) * 2000-01-14 2001-07-19 Worcester Polytechnic Institute Method of preparing compounds using cavitation and compounds formed therefrom
US20090088594A1 (en) * 2006-04-18 2009-04-02 Sk Energy Co., Ltd Bismuth molybdate-based catalysts, method of preparing thereof and method of preparing 1,3-butadiene using thereof
CN109012654A (en) * 2018-08-22 2018-12-18 延安大学 A kind of bismuth molybdate catalysis material and preparation method thereof rich in surface oxygen defect
CN109865513A (en) * 2017-12-05 2019-06-11 中国科学院金属研究所 A kind of bismuth molybdate material and its preparation method and application of richness surface Lacking oxygen
CN110871066A (en) * 2019-12-11 2020-03-10 南昌航空大学 Preparation method of all-solid-state self-growing bismuth molybdate ultrathin nanosheet semiconductor photocatalyst material

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001051202A1 (en) * 2000-01-14 2001-07-19 Worcester Polytechnic Institute Method of preparing compounds using cavitation and compounds formed therefrom
US20090088594A1 (en) * 2006-04-18 2009-04-02 Sk Energy Co., Ltd Bismuth molybdate-based catalysts, method of preparing thereof and method of preparing 1,3-butadiene using thereof
CN109865513A (en) * 2017-12-05 2019-06-11 中国科学院金属研究所 A kind of bismuth molybdate material and its preparation method and application of richness surface Lacking oxygen
CN109012654A (en) * 2018-08-22 2018-12-18 延安大学 A kind of bismuth molybdate catalysis material and preparation method thereof rich in surface oxygen defect
CN110871066A (en) * 2019-12-11 2020-03-10 南昌航空大学 Preparation method of all-solid-state self-growing bismuth molybdate ultrathin nanosheet semiconductor photocatalyst material

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
GUI LI ET AL.: ""Creation of rich oxygen vacancies in bismuth molybdate nanosheets to boost the photocatalytic nitrogen fixation performance under visible light illumination"", 《CHEMICAL ENGINEERING JOURNAL》 *
汪圣尧: ""Bi基材料表面氧空位的调控及其光催化性能研究"", 《中国博士学位论文全文数据库（工程科技Ⅰ辑）》 *
赵晨光 等: ""通过化学蚀刻提高 Bi2WO6/Bi2MoO6光催化活性的机理探析"", 《哈尔滨师范大学自然科学学报》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114700067A (en) * 2022-04-20 2022-07-05 重庆文理学院 Oxygen-rich vacancy bismuth molybdate photocatalytic material and preparation method and application thereof
CN114700067B (en) * 2022-04-20 2023-05-23 重庆文理学院 Bismuth molybdate photocatalytic material with oxygen-enriched vacancy and preparation method and application thereof

Similar Documents

Publication Publication Date Title
US11628432B2 (en) Nitrogen-doped mesoporous carbon-coated titanium dioxide composite photocatalyst, a preparation method and use thereof
CN113262808B (en) Water-soluble graphite-phase carbon nitride nanosheet catalyst for efficiently removing formaldehyde at room temperature and preparation method thereof
CN113000046A (en) Modified manganese-based mullite catalyst for synergistic purification of nitrogen oxides and volatile organic compounds, and preparation method and application thereof
CN110575832A (en) Preparation method and application of silver-titanium dioxide-nano diamond composite photocatalyst
CN110665531A (en) Pt/g-C3N4/CeO2Composite photocatalyst and preparation method and application thereof
CN109158117B (en) Full-spectrum-response double-doped lanthanum fluoride/attapulgite up-conversion composite photocatalytic material and preparation method and application thereof
CN112973670A (en) Preparation method of bismuth molybdate material for removing NO through photocatalysis and product
CN110918099A (en) Method for treating hexavalent chromium-containing wastewater through photocatalytic reduction of nickel oxide-nickel cobaltate-black titanium dioxide composite
CN111659455B (en) Preparation method and application of Co-CDs @ NM photocatalyst
CN106542584A (en) A kind of preparation method of rich defect cobalt oxide photocatalyst
CN112844368B (en) ZnMoO with adjustable oxygen vacancy concentration 4 Photocatalyst, preparation method and application thereof
CN113058630B (en) Preparation method and application of photocatalyst suitable for efficiently removing formaldehyde at room temperature
CN115779946A (en) Boron-nitrogen co-doped titanium dioxide nanotube composite material and preparation method thereof
CN113797910B (en) Defect-containing nano microspherical perovskite catalyst and preparation method and application thereof
CN114160104A (en) Kiln flue gas CO2Trapping and utilizing coupling material and application thereof
CN113198461A (en) Nano MnO2PTFE composite material and preparation method and application thereof
CN111137920A (en) Black Ta2O5And preparation method and application thereof
CN115350704B (en) Ag (silver) alloy 2 O cluster modified perovskite-like hydroxide visible light catalyst, preparation method and application
CN107469762B (en) Composite material of micro-supported titanium oxide and silica gel and preparation method thereof
CN115501869B (en) Heterojunction type photocatalyst and preparation method thereof
CN109603904A (en) A kind of preparation and application of high efficiency purification adipic acid smoke catalytic agent
CN113492011B (en) Method for removing Nitric Oxide (NO) by defect-containing perovskite material through photocatalysis
CN116272860B (en) VOCs treated regenerated activated carbon and preparation method thereof
CN113477237B (en) Preparation method of titanium dioxide/molybdenum trioxide heterojunction and application of titanium dioxide/molybdenum trioxide heterojunction in photocatalytic desulfurization
CN115805067A (en) Photocatalyst for efficiently degrading toluene and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication

Application publication date: 20210618

RJ01 Rejection of invention patent application after publication