Microspherical Bi3O4Preparation and application of Cl/BiOI compound
阅读说明：本技术 微球状Bi3O4Cl/BiOI复合物的制备及应用 (Microspherical Bi3O4Preparation and application of Cl/BiOI compound ) 是由 程良良 肖新颜 于 2020-05-21 设计创作，主要内容包括：本发明公开了一种微球状Bi<Sub>3</Sub>O<Sub>4</Sub>Cl/BiOI复合物的制备及应用。该方法包括将碘化钾溶液滴入含有硝酸铋和Bi<Sub>3</Sub>O<Sub>4</Sub>Cl的乙二醇溶液,加热反应后得到Bi<Sub>3</Sub>O<Sub>4</Sub>Cl/BiOI复合物。本发明提出的制备方法不涉及重金属离子和高分子模板剂,不会造成二次污染,制备方法相对简单并充分发挥了原位生长法的优势,制备出的复合物结构与性质稳定,对甲基橙的催化活性高,有望于工业废水处理上的运用。(The invention discloses a microspherical Bi 3 O 4 Preparation and application of Cl/BiOI compound. The method comprises dropping potassium iodide solution into solution containing bismuth nitrate and Bi 3 O 4 Heating and reacting Cl in ethylene glycol to obtain Bi 3 O 4 Cl/BiOI composite. The preparation method provided by the invention does not relate to heavy metal ions and a high-molecular template agent, does not cause secondary pollution, is relatively simple, and gives full play to in-situ generationThe advantages of the long method are that the prepared compound has stable structure and property and high catalytic activity to methyl orange, and is expected to be applied to industrial wastewater treatment.)
1. Microspherical Bi3O4The preparation method of the Cl/BiOI compound is characterized by comprising the following steps:
adding potassium iodide solution into bismuth nitrate and Bi3O4Heating and reacting in ethylene glycol solution of Cl to obtain Bi3O4Cl/BiOI composite.
2. The microspheroidal Bi of claim 13O4A method for producing a Cl/BiOI composite, characterized in that, in terms of mass fraction, Bi3O4Cl：BiOI＝1:3-20。
3. The microspheroidal Bi of claim 13O4The preparation method of the Cl/BiOI compound is characterized in that the heating temperature is 100-160 ℃.
4. The microspheroidal Bi of claim 13O4The preparation method of the Cl/BiOI compound is characterized in that the reaction time is 3-12 h.
5. The microspheroidal Bi of claim 13O4A method for preparing a Cl/BiOI composite, characterized in that said microspheroidal Bi3O4The particle size of the Cl/BiOI compound is 2-4 mu m.
6. The microspheroidal Bi of claim 13O4A method for preparing a Cl/BiOI composite, characterized in that said Bi3O4The preparation method of Cl is as follows:
(1) dripping bismuth nitrate solution into ammonium chloride solution, mixing and heatingObtaining Bi after reaction3O4A precursor of Cl;
(2) adding Bi3O4Obtaining Bi by Cl precursor at the high temperature of 400-550 ℃ for 1-5h3O4And (3) Cl nanosheets.
7. The microspheroidal Bi of claim 63O4The preparation method of the Cl/BiOI compound is characterized in that the heating reaction in the step (1) is carried out for 6-24h at the temperature of 140-200 ℃.
8. The method for degrading methyl orange is characterized by comprising the following steps:
production method of microspherical Bi according to any one of claims 1 to 63O4A Cl/BiOI complex;
the prepared microspherical Bi3O4The Cl/BiOI complex degrades methyl orange under light irradiation.
9. The method for degrading methyl orange of claim 8, wherein the micro-spherical Bi is3O4The dosage ratio of the Cl/BiOI compound to the methyl orange is more than 100: 3.
10. The method for degrading methyl orange according to claim 9, wherein the microspherical Bi is obtained after 90min3O4The degradation rate of the Cl/BiOI compound to methyl orange is higher than 82%.
Technical Field
The invention belongs to the field of visible light catalysis, and particularly relates to microspherical Bi3O4An X/BiOX compound and a preparation method and application thereof, which are used for photocatalytic degradation of organic matters, and belong to the field of composite materials and the field of photocatalysis.
Background
The photocatalysis technology can utilize abundant solar energy, andno secondary pollution is generated, and thus, the problem of water pollution using the photocatalytic technology is drawing more and more attention. BiOX (Cl, Br and I) is a class of Sillen compounds with a special layered structure in which [ Bi ] is present2O2]The layers are interleaved between two halogen atoms and are staggered so that the BiOX has an anisotropic, relatively loose structure. The structure affects the properties, and the BiOX shows the properties that adjacent atoms and orbitals are easy to polarize and electrons and holes are easy to separate. Wherein, Bi3O4Cl is one of the Sillen groups of compounds consisting of [ Bi3O4]The unique crystal structure, which is composed of the halide ion layers in a staggered arrangement, provides enough space to polarize the relevant atoms and orbitals, forming a self-built internal electric field. The formed electric field can promote the separation and the transportation of charge carriers and improve the photocatalytic performance. Although Bi3O4Cl has a proper valence band structure, but has weak visible light absorption capacity and low photon-generated carrier mobility, so that the photocatalysis capacity is low, and the practical application is greatly limited.
The BiOI is a Sillen group compound with a narrow band gap (1.7-1.9eV), has wide visible light absorption range, strong capability and high photogenerated carrier mobility, and is usually used for modifying semiconductor photocatalysts with wide band gap, weak visible light absorption capability and low photogenerated carrier mobility. The method utilizes the advantages of the BiOI and the similarity between the structures to realize the BiOI and the Bi by a hydrothermal method3O4Cl composition obviously promotes Bi3O4The photocatalytic properties of Cl.
CN 106268880A uses polyvinylpyrrolidone (PVP) as a template agent, and adopts a method of sodium carbonate to adjust the pH value to prepare microspherical Bi3O4The catalyst is a Cl/BiOCl visible light catalyst, and the catalyst shows higher degradation activity to easily degradable rhodamine B. Similarly, CN 107890877A respectively prepares Bi by a hydrothermal-calcining method and a hydrothermal method3O4Preparing Bi by hydrothermal method with Cl nanosheet and CdS nanosphere and polyvinylpyrrolidone (PVP) as template agent3O4The composite photocatalyst can degrade 81.2 percent of ciprofloxacin within 120 min.However, there is a need in the art for a solution that does not use templating agents and toxic heavy metal ions, and does not cause secondary contamination.
Disclosure of Invention
The invention introduces the cheap and environment-friendly BiOI to construct Bi3O4Method for improving Bi by Cl/BiOI heterojunction3O4The photocatalysis performance of Cl is expanded, and Bi is expanded3O4The application range of Cl, and simultaneously, no PVP template agent and toxic ions are involved, and secondary pollution is avoided. Microspheroidal Bi prepared herein3O4Cl/BiOI composite versus Bi alone3O4Cl and the photocatalytic performance is remarkably improved, the higher removal rate of the water pollutant methyl orange is remarkably increased, and the method has potential application value in the aspect of wastewater treatment.
The purpose of the invention is realized by the following technical scheme:
microspherical Bi3O4The preparation method of the Cl/BiOI compound comprises the following steps:
dripping potassium iodide solution into bismuth nitrate and Bi3O4Heating and reacting Cl in ethylene glycol to obtain Bi3O4Cl/BiOI composite.
Preferably, Bi is present in mass fraction3O4Cl：BiOI＝1:3-20。
Preferably, the heating temperature is 100-160 ℃.
Preferably, the reaction time is 3 to 12 hours.
Preferably, the microspherical Bi3O4The particle size of the Cl/BiOI compound is 2-4 mu m.
Preferably, said Bi3O4The preparation method of Cl is as follows:
(1) dripping bismuth nitrate solution into ammonium chloride solution, mixing and heating for reaction to obtain Bi3O4A precursor of Cl;
(2) adding Bi3O4Obtaining Bi by Cl precursor at the high temperature of 400-550 ℃ for 1-5h3O4And (3) Cl nanosheets.
More preferably, the heating reaction in step (1) is carried out at 140 ℃ and 200 ℃ for 6-24 h.
A method for degrading methyl orange comprises the following steps:
preparation of microspherical Bi according to the above preparation method3O4A Cl/BiOI complex;
the prepared microspherical Bi3O4The Cl/BiOI complex degrades methyl orange under light irradiation.
Preferably, the microspherical Bi3O4The dosage ratio of the Cl/BiOI compound to the methyl orange is more than 100: 3.
More preferably, after 90min, Bi is microspherical3O4The degradation rate of the Cl/BiOI compound to methyl orange is higher than 82%.
Compared with the prior art, the invention has the following advantages and technical effects:
(1) the invention introduces a cheap and environment-friendly substance BiOI to construct Bi3O4Cl-based complex, solves the problem of Bi3O4Weak Cl visible light absorption capacity and small light response range.
(2) Prepared microspherical Bi3O4Cl/BiOI composite photocatalyst, Bi3O4Cl and BiOI form a Z-shaped heterojunction, so that the separation efficiency of a photon-generated carrier is improved, the specific surface area of the catalyst is increased, and more catalytic reaction active sites are generated.
(3) The preparation method of the invention does not relate to any template agent and toxic heavy metal ions, and does not cause secondary pollution.
(4) Microspherical Bi obtained by the invention3O4The degradation rate of the Cl/BiOI compound to 10mg/L methyl orange within 90min can reach 99.8 percent, and the Cl/BiOI compound has a great potential application value.
Drawings
FIG. 1 shows the microspherical Bi prepared in example 13O4Scanning electron microscopy of Cl/BiOI complexes.
FIG. 2 (a) shows the microspherical Bi prepared in example 13O4Transmission electron micrograph of Cl/BiOI composite, (b) is the area of (a)Partially enlarged view, and (c) is the microspherical Bi prepared in example 13O4High power transmission electron microscope image of Cl/BiOI composite.
FIG. 3 shows Bi prepared in example 1 of the present invention3O4UV-VIS absorption spectrum of Cl/BiOI composite.
FIG. 4 shows the microspherical Bi prepared in example 13O4Fluorescence spectrum of Cl/BiOI complex.
FIG. 5 (a) shows the microspherical Bi prepared in example 13O4Specific surface area diagram of Cl/BiOI composite, (b) microspherical Bi prepared in example 13O4Pore size distribution of Cl/BiOI composites.
FIG. 6 shows different Bi prepared by various embodiments of the present invention3O4Bi of Cl content3O4Graph of the Cl/BiOI complex on the photocatalytic degradation of methyl orange.
Detailed Description
The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.