CN114160134A - In-situ synthesis of flower-shaped AgBiO3/NaBiO3Photocatalytic material and application thereof - Google Patents

Abstract

The invention discloses an in-situ synthesis method of flower-shaped AgBiO₃/NaBiO₃A photocatalytic material and application thereof relate to the technical field of photocatalysis. The material is a compound formed by compounding silver bismuthate and sodium bismuthate; the mass percentage of the silver bismuthate in the compound is 10-50%. The invention is based on insoluble sodium salt NaBiO₃By constructing AgBiO₃/NaBiO₃Complexes using NaBiO₃And AgBiO₃The oxidability of the catalyst per se exerts the capability of removing pollutants by the cooperation of direct oxidation and catalytic oxidation, provides additional active species in the degradation process, improves the total efficiency of removing pollutants, and has important scientific theoretical value for developing the practical application of organic pollutant wastewater treatment.

Description

In-situ synthesis of flower-shaped AgBiO3/NaBiO3Photocatalytic material and application thereof

Technical Field

The invention relates to the technical field of photocatalysis, in particular to an in-situ method for synthesizing flower AgBiO₃/NaBiO₃A photocatalytic material, a preparation method and application thereof.

Background

The environmental problem of organic pollution in the water phase seriously threatens the ecological sustainable development of society and the life health of human beings, and is highly valued by all countries in the world. The environmental protection law of China's origin stipulates strict standards for water-phase pollutants. Persistent organic pollutants in wastewater have high environmental toxicity, difficult degradability, and the effect of transmitting and accumulating through food chains, and the traditional biological or physical and chemical methods are difficult to effectively eliminate the pollutants. Therefore, the development of advanced technologies for effectively eliminating such contaminants is not only an important scientific problem, but also can solve the practical application problems faced by the modern chemical and pharmaceutical synthesis industries.

The advanced oxidation technology is a technology which can generate oxidation free radicals such as hydroxyl or sulfate radical and the like in various ways under the reaction conditions of high temperature and high pressure, electricity, sound, light irradiation, catalysts and the like so that macromolecular refractory organic matters are oxidized into low-toxicity or non-toxic micromolecular substances. But it requires light, microwaves, electron-based catalysts or chemicals (e.g. H)₂O₂，Na₂S₂O₈) The input of equal energy or material severely limits the realityAnd (4) practical application. Develops a new method for efficiently removing organic pollutants in wastewater, does not add extra energy and reagents, is beneficial to reducing the cost of water treatment, and promotes practical application. Due to the high mobility of photo-electrons, the current research focuses more on the photocatalytic degradation of pollutants in water by visible light, and deep research on the potential catalytic performance and application of the pollutants is lacked. Aiming at the problem of low efficiency or incomplete treatment of organic matters in the prior wastewater, AgBiO is constructed₃/NaBiO₃The composite catalyst is used for researching the removal application of the composite catalyst to the organic matters in the wastewater under the conditions of dark reaction and light reaction, and the oxidation performance and the photocatalysis performance of the composite catalyst are utilized to cooperatively remove the organic matters in the wastewater with high efficiency, so that the composite catalyst has important scientific theoretical value and practical significance for developing the practical application of organic pollutant wastewater treatment.

Disclosure of Invention

The invention aims to solve the defects in the background technology and provides an in-situ method for synthesizing flower AgBiO₃/NaBiO₃A photocatalytic material, a preparation method and application thereof. The photocatalytic material is based on an insoluble sodium salt NaBiO which is one of the new members of the perovskite family₃By constructing AgBiO₃/NaBiO₃Complexes using NaBiO₃And AgBiO₃The oxidability of the catalyst per se exerts the capability of removing pollutants by the cooperation of direct oxidation and catalytic oxidation, provides additional active species in the degradation process, improves the total efficiency of removing pollutants, and has important scientific theoretical value for developing the practical application of organic pollutant wastewater treatment.

The first purpose of the invention is to provide an in-situ method for synthesizing flower-shaped AgBiO₃/NaBiO₃The photocatalytic material is a compound formed by compounding silver bismuthate and sodium bismuthate; the mass percentage of the silver bismuthate in the compound is 10-50%.

The second purpose of the invention is to provide an in-situ method for synthesizing flower-shaped AgBiO₃/NaBiO₃The preparation method of the photocatalytic material comprises the following steps: dispersing sodium bismuthate into a hydrosolvent in a dark environment, adding a silver salt solution, and stirring for reaction for 0.5-1 h to obtain the sodium bismuthate silver-silver mixed materialIn-situ synthesis of flower-shaped AgBiO₃/NaBiO₃A photocatalytic material.

Preferably, the molar ratio of the sodium bismuthate to the silver salt is 1: 0.1 to 1.

More preferably, the silver salt is silver nitrate.

Preferably, after the reaction is finished, the reactant is circularly washed by absolute ethyl alcohol and distilled water, and then dried for 6 hours in vacuum at 80 ℃.

The third purpose of the invention is to provide an in-situ method for synthesizing flower-shaped AgBiO₃/NaBiO₃The application of the photocatalytic material in the treatment of organic pollutant wastewater.

Compared with the prior art, the invention has the beneficial effects that:

the invention provides a method for synthesizing flower-shaped AgBiO by an in-situ method₃/NaBiO₃A photocatalytic material. The photocatalytic material is based on an insoluble sodium salt NaBiO which is one of the new members of the perovskite family₃By constructing AgBiO₃/NaBiO₃Complexes using NaBiO₃And AgBiO₃The oxidability of the catalyst per se exerts the capability of removing pollutants by the cooperation of direct oxidation and catalytic oxidation, improves the total efficiency of removing pollutants, and has important scientific theoretical value for developing the practical application of organic pollutant wastewater treatment.

AgBiO prepared by ion exchange method₃/NaBiO₃The photocatalytic material does not need extra energy or extra reagents in the wastewater treatment process, and is beneficial to reducing the cost of water treatment.

Drawings

FIG. 1 shows the photocatalytic materials and AgBiO provided in examples 1 to 4₃And NaBiO₃XRD pattern of (a);

FIG. 2 is NaBiO₃FE-SEM picture of (1);

FIG. 3 is AgBiO₃SEM picture of (1);

FIG. 4 is an SEM image of the photocatalytic material provided in example 3;

FIG. 5 is an XPS total spectrum of the photocatalytic material provided in example 3;

FIG. 6 shows examples 1 to 4Provided photocatalytic material and AgBiO₃And NaBiO₃An EIS curve graph fitted by zview software;

FIG. 7 shows the in-situ synthesis of flower-shaped AgBiO provided in examples 1 to 4₃/NaBiO₃Photocatalytic material and AgBiO₃And NaBiO₃Degradation effect on tetracycline under the conditions of dark reaction for 30min and visible light illumination for 20 min;

FIG. 8 is the in-situ synthesis of flower-like AgBiO provided in examples 1-4₃/NaBiO₃Photocatalytic material and AgBiO₃And NaBiO₃Degradation effect on tetracycline under dark reaction conditions;

FIG. 9 is the in situ synthesis of flower-like AgBiO provided in example 3₃/NaBiO₃The effect diagram of the photocatalytic material on removing bisphenol A, norfloxacin, ofloxacin, ciprofloxacin and tetracycline simulation wastewater is shown.

Detailed Description

In order to make the technical solutions of the present invention better understood and enable those skilled in the art to practice the present invention, the following embodiments are further described, but the present invention is not limited to the following embodiments.

It should be noted that the experimental methods in the following examples are all conventional methods unless otherwise specified; the reagents and materials used are commercially available, unless otherwise specified.

Example 1

Under a dark environment, 2g of NaBiO₃·2H₂O was dissolved in 40ml of distilled water, magnetically stirred, and 0.198ml of 3mol/LAgNO was added dropwise thereto₃Magnetically stirring the solution for 30min, then carrying out centrifugal washing, repeatedly washing for six times by using absolute ethyl alcohol and distilled water, finally placing the solution in a vacuum drying oven, and carrying out vacuum drying for 6h at the temperature of 80 ℃ to obtain AgBiO₃In-situ synthesis of flower-shaped AgBiO with content of 10%₃/NaBiO₃Photocatalytic material (AgBiO)₃/NaBiO₃)。

Example 2

Under a dark environment, 2g of NaBiO₃·2H₂Dissolving O in 40ml of distilled water, and magnetically stirring0.396ml of 3mol/LAgNO was added dropwise thereto₃Magnetically stirring the solution for 30min, then carrying out centrifugal washing, repeatedly washing for six times by using absolute ethyl alcohol and distilled water, finally placing the solution in a vacuum drying oven, and carrying out vacuum drying for 6h at the temperature of 80 ℃ to obtain AgBiO₃AgBiO with content of 20%₃/NaBiO₃And (c) a complex.

Example 3

Under a dark environment, 2g of NaBiO₃·2H₂O was dissolved in 40ml of distilled water, magnetically stirred, and 0.594ml of 3mol/LAgNO was added dropwise thereto₃Magnetically stirring the solution for 30min, then carrying out centrifugal washing, repeatedly washing for six times by using absolute ethyl alcohol and distilled water, finally placing the solution in a vacuum drying oven, and carrying out vacuum drying for 6h at the temperature of 80 ℃ to obtain AgBiO₃AgBiO with content of 30%₃/NaBiO₃And (c) a complex.

Example 4

Under a dark environment, 2g of NaBiO₃·2H₂O in 40ml of distilled water, magnetically stirring, and adding 0.99ml of 3mol/LAgNO dropwise thereto₃Magnetically stirring the solution for 30min, then carrying out centrifugal washing, repeatedly washing for six times by using absolute ethyl alcohol and distilled water, finally placing the solution in a vacuum drying oven, and carrying out vacuum drying for 6h at the temperature of 80 ℃ to obtain AgBiO₃AgBiO with 50% content₃/NaBiO₃And (c) a complex.

To illustrate the in-situ synthesis of flower-shaped AgBiO provided by the invention₃/NaBiO₃The related performance of the photocatalytic material, the photocatalytic material provided in examples 1 to 4 was tested for related performance, as shown in fig. 1 to 9.

In the following performance test, AgBiO was used₃The preparation method comprises the following steps: under a dark environment, 2g of NaBiO₃·2H₂O in 40ml of distilled water, magnetically stirring, and adding 2ml of 3mol/LAgNO dropwise thereto₃Magnetically stirring the solution for 30min, then carrying out centrifugal washing, repeatedly washing for six times by using absolute ethyl alcohol and distilled water, finally placing the solution in a vacuum drying oven, and carrying out vacuum drying for 6h at the temperature of 80 ℃ to obtain AgBiO₃；NaBiO₃Purchased from Shanghai AlatinshengChemical science and technology, Inc.

FIG. 1 shows the photocatalytic materials and AgBiO provided in examples 1 to 4₃And NaBiO₃XRD pattern of (a);

from FIG. 1, it can be seen that the diffraction peaks of sodium bismuthate are respectively at 11.9 °, 18.2 °, 21.8 °, 30.2 °, 30.3 °, 31.9 °, 40.0 °, 49.0 °, and 56.9 °, which are ascribed to NaBiO₃.2H₂O (JCPDS30-1161) has (001), (100), (101), (102), (110), (111), (201), (1103) and (300) crystal planes. AgBiO obtained by ion exchange₃Has a reaction with NaBiO₃.2H₂O similar phase structure. AgBiO₃/NaBiO₃XRD pattern of the complex showed the presence of AgBiO in the complex₃And NaBiO₃And with AgBiO in the complex₃The content is increased, the strength of the characteristic peak of the sodium bismuthate is gradually weakened, and the strength of the characteristic peak of the silver bismuthate is gradually strengthened, which shows that the sodium bismuthate and the silver bismuthate are compounded together.

FIG. 2 is NaBiO₃FE-SEM picture of (1); FIG. 3 is AgBiO₃SEM picture of (1); FIG. 4 is an SEM image of the photocatalytic material provided in example 3; as can be seen from figure 2, the sodium bismuthate is in a nano flower shape formed by crossing nano sheets, and the thickness of a single nano sheet is between 15 and 23 nm. FIG. 3 is AgBiO₃The FE-SEM picture of (sodium bismuthate) shows that the silver bismuthate replicates the nanometer flower shape of the sodium bismuthate, but the thickness of a single nanometer sheet is between 14 and 21nm and is slightly thinner than that of NaBiO₃Nanosheets. FIG. 4 is a 30% AgBiO₃/NaBiO₃FE-SEM picture of (1), AgBiO can be observed₃/NaBiO₃The material forms a Feng-shaped pattern which takes a sodium bismuthate sheet structure as a main body and combines two sides of silver bismuthate, and the Feng-shaped structure has larger specific surface area. AgBiO formed by crossing single-substance nanosheets₃/NaBiO₃The composite material has the advantages that the two substances are combined more tightly and are compounded more uniformly, and the transmission and transfer of photo-generated charges are facilitated.

FIG. 5 is an XPS total spectrum of the photocatalytic material provided in example 3; from FIG. 5, it can be observed that at 30% AgBiO₃/NaBiO₃There are five elements of Na, Bi, O, C and N.

FIG. 6 shows an embodimentExamples 1 to 4 provide photocatalytic materials and AgBiO₃And NaBiO₃An EIS curve graph fitted by zview software; as can be seen from FIG. 6, NaBiO is observed₃、AgBiO₃、10％AgBiO₃/NaBiO₃、20％AgBiO₃/NaBiO₃、30％AgBiO₃/NaBiO₃And 50% AgBiO₃/NaBiO₃The fitted EIS curve arc radiuses are reduced in sequence, and the photoproduction charge separation capacity is increased in sequence.

To illustrate the in-situ synthesis of flower-shaped AgBiO provided by the invention₃/NaBiO₃The catalytic effect of the photocatalytic material is evaluated by tetracycline, bisphenol A, norfloxacin, ofloxacin and ciprofloxacin which are degradation targets. In the experiment, a 500W xenon lamp is used for providing a visible light source (lambda is more than or equal to 420nm), and the initial concentration of pollutants is 20 mg/L; mixing 20mgNaBiO₃、AgBiO₃Example 1 provides 10% AgBiO₃/NaBiO₃Example 2 provides 20% AgBiO₃/NaBiO₃Example 3 provides 30% AgBiO₃/NaBiO₃Example 4 provides 50% AgBiO₃/NaBiO₃The catalytic materials are respectively and uniformly dispersed in a quartz test tube containing 40mL of tetracycline aqueous solution (20mg/L), and are placed in the dark to be stirred for 30min to achieve adsorption-desorption balance. Then the light source is turned on to carry out the photocatalytic reaction. Taking 1mL of sample every 5min in the dark reaction and light reaction processes, centrifuging, taking supernatant, and measuring and analyzing at the maximum absorption wavelength of 360nm by using a micro quartz cuvette (1mL) and a Shanghai apparatus electric L5 ultraviolet-visible spectrophotometer so as to evaluate the catalytic performance of the sample. The dark reaction is a reaction carried out in the absence of light, and the other conditions are the same as above. See FIGS. 7-9.

FIG. 7 shows the in-situ synthesis of flower-shaped AgBiO provided in examples 1 to 4₃/NaBiO₃Photocatalytic material and AgBiO₃And NaBiO₃Degradation effect on tetracycline under the conditions of dark reaction for 30min and visible light illumination for 20 min;

as can be seen from FIG. 7, NaBiO₃、AgBiO₃、10％AgBiO₃/NaBiO₃、20％AgBiO₃/NaBiO₃、30％AgBiO₃/NaBiO₃、50％AgBiO₃/NaBiO₃The removal efficiency of tetracycline in 30min dark reaction is as follows: 27%, 60%, 32%, 48%, 63%, 56% and 30%. Wherein 30% AgBiO is added at 30min₃/NaBiO₃Has the best degradation effect on tetracycline. Then NaBiO is carried out after the visible light illumination reaction for 20min₃、AgBiO₃、10％AgBiO₃/NaBiO₃、20％AgBiO₃/NaBiO₃、30％AgBiO₃/NaBiO₃、50％AgBiO₃/NaBiO₃The degradation efficiency of the catalyst on tetracycline is respectively as follows: 36%, 71%, 41%, 65%, 73%, 69%. It can be seen from this experiment that 30% AgBiO₃/NaBiO₃The degradation efficiency of the composite photocatalyst reaches 73% at most under the reaction of dark conditions and light conditions.

FIG. 8 is the in-situ synthesis of flower-like AgBiO provided in examples 1-4₃/NaBiO₃Photocatalytic material and AgBiO₃And NaBiO₃Degradation effect on tetracycline under dark reaction conditions; as can be seen from FIG. 8, NaBiO was obtained 50min after the dark reaction₃、AgBiO₃、10％AgBiO₃/NaBiO₃、20％AgBiO₃/NaBiO₃、30％AgBiO₃/NaBiO₃、50％AgBiO₃/NaBiO₃The removal efficiency of tetracycline is respectively as follows: 35%, 68%, 40%, 52%, 70%, 61%. It can be seen from this experiment that 30% AgBiO₃/NaBiO₃The highest degradation efficiency of the composite catalyst on the four rings under dark condition reaction reaches 70 percent.

FIG. 9 is the in situ synthesis of flower-like AgBiO provided in example 3₃/NaBiO₃The effect diagram of the photocatalytic material on removing bisphenol A, norfloxacin, ofloxacin, ciprofloxacin and tetracycline simulation wastewater is shown.

As can be seen from FIG. 9, the concentration of the contaminants was 20mg/L, and 30% AgBiO was obtained under dark reaction conditions of 30min and light reaction conditions of 20min₃/NaBiO₃For bisphenol A, norfloxacin, ofloxacin, ciprofloxacin and tetracyclineThe removal efficiencies of the simulated wastewater were 38.8%, 39.7%, 19.8%, 50.0%, 71.5%, respectively.

In conclusion, the invention provides an in-situ method for synthesizing flower-shaped AgBiO₃/NaBiO₃A photocatalytic material. The photocatalytic material is based on an insoluble sodium salt NaBiO which is one of the new members of the perovskite family₃By constructing AgBiO₃/NaBiO₃Complexes using NaBiO₃And AgBiO₃The oxidability of the catalyst per se exerts the capability of removing pollutants by the cooperation of direct oxidation and catalytic oxidation, provides additional active species in the degradation process, improves the total efficiency of removing pollutants, and has important scientific theoretical value for developing the practical application of organic pollutant wastewater treatment.

The invention adopts an ion exchange method to synthesize flower AgBiO in situ₃/NaBiO₃The photocatalytic material does not need extra energy or extra reagents in the wastewater treatment process, and is beneficial to reducing the cost of water treatment.

The present invention describes preferred embodiments and effects thereof. Additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (6)

1. In-situ synthesis method of flower-shaped AgBiO₃/NaBiO₃The photocatalytic material is characterized in that the photocatalytic material is a compound formed by compounding silver bismuthate and sodium bismuthate; the mass percentage of the silver bismuthate in the compound is 10-50%.

2. A process as claimed in claim 1Synthesis of flower-shaped AgBiO by using site method₃/NaBiO₃The preparation method of the photocatalytic material is characterized by comprising the following steps of:

dispersing sodium bismuthate into a hydrosolvent in a dark environment, adding a silver salt solution, and stirring for reaction for 0.5-1 h to obtain the flower-shaped AgBiO synthesized by the in-situ method₃/NaBiO₃A photocatalytic material.

3. The in situ synthesis of flower-like AgBiO according to claim 2₃/NaBiO₃The preparation method of the photocatalytic material is characterized in that the molar ratio of the sodium bismuthate to the silver salt is 1: 0.1 to 1.

4. The in situ synthesis of flower-like AgBiO according to claim 3₃/NaBiO₃The preparation method of the photocatalytic material is characterized in that the silver salt is silver nitrate.

5. The in situ synthesis of flower-like AgBiO according to claim 2₃/NaBiO₃The preparation method of the photocatalytic material is characterized in that after the reaction is finished, reactants of the photocatalytic material are circularly washed by absolute ethyl alcohol and distilled water, and then are dried for 6 hours in vacuum at 80 ℃.

6. The in-situ synthesis method of flower-shaped AgBiO according to claim 1₃/NaBiO₃The application of the photocatalytic material in the treatment of organic pollutant wastewater.

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