阅读说明：本技术 一种钨酸铋纳米粉体的制备方法 (Preparation method of bismuth tungstate nano powder ) 是由 鲍亮 张怀伟 白王峰 吴诗婷 元勇军 陈逸凡 于 2020-12-29 设计创作，主要内容包括：本发明公开了一种钨酸铋纳米粉体的制备方法,其包括以下步骤：1)将硝酸铋溶于乙二醇中,形成硝酸铋溶液；2)将钨酸钠溶解于去离子水中,形成钨酸钠溶液；3)将步骤1)所得硝酸铋溶液倒入步骤2)所得钨酸钠溶液中,搅拌后转移到高压反应釜中；4)将配置有高压反应物料的反应釜密闭,进行热处理,后降至室温,过滤,依次用去离子水、无水乙醇清洗,烘干,得到钨酸铋纳米粉体。本发明工艺过程简单,易于控制,无环境污染,成本低,易于规模化生产。产品质量稳定,纯度高,粉体颗粒分散性好。(The invention discloses a preparation method of bismuth tungstate nano powder, which comprises the following steps: 1) dissolving bismuth nitrate in ethylene glycol to form a bismuth nitrate solution; 2) dissolving sodium tungstate in deionized water to form a sodium tungstate solution; 3) pouring the bismuth nitrate solution obtained in the step 1) into the sodium tungstate solution obtained in the step 2), stirring and transferring to a high-pressure reaction kettle; 4) and (3) sealing the reaction kettle equipped with the high-pressure reaction material, carrying out heat treatment, cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying to obtain the bismuth tungstate nano powder. The method has the advantages of simple process, easy control, no environmental pollution, low cost and easy large-scale production. The product has stable quality, high purity and good powder particle dispersibility.)

1. A preparation method of bismuth tungstate nano powder is characterized by comprising the following steps:

1) dissolving bismuth nitrate in ethylene glycol to form a bismuth nitrate solution;

2) dissolving sodium tungstate in deionized water to form a sodium tungstate solution;

3) pouring the bismuth nitrate solution obtained in the step 1) into the sodium tungstate solution obtained in the step 2), stirring and transferring to a high-pressure reaction kettle;

4) and (3) sealing the reaction kettle equipped with the high-pressure reaction material, carrying out heat treatment, cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying to obtain the bismuth tungstate nano powder.

2. The method for preparing the bismuth tungstate nano powder as claimed in claim 1, wherein in the step 1), the concentration of the bismuth nitrate solution is 0.1-0.2 mol/L.

3. The method for preparing the bismuth tungstate nano powder as claimed in claim 1, wherein in the step 2), the concentration of the sodium tungstate solution is 0.01-0.02 mol/L.

4. The preparation method of the bismuth tungstate nanopowder as claimed in claim 1, wherein in the step 3), the molar ratio of the sodium tungstate to the bismuth nitrate is 1: 1-1: 2.

5. The method for preparing bismuth tungstate nanopowder as recited in claim 1, wherein in step 4), the heat treatment is carried out at 120-140 ℃ for 14-20 hours.

6. The method for preparing bismuth tungstate nanopowder as claimed in claim 1 or 5, wherein in step 4), the bismuth tungstate nanopowder is obtained by drying at 60-80 ℃.

Technical Field

The invention belongs toThe technical field of inorganic non-metallic material manufacture, in particular to bismuth tungstate (Bi)₂WO₆) A method for preparing nano powder.

Background

Energy is the most important material basis for human survival development, and with the increasing shortage of traditional fossil energy and the increasing demand of human for energy, new energy, particularly renewable energy, becomes a hot spot for the current social and scientific development. Bismuth tungstate (Bi)₂WO₆) The photocatalyst is a novel photocatalyst with narrow forbidden band width, and can simultaneously generate response in ultraviolet light and visible light regions. Bi₂WO₆The catalyst is also a simple Aurivillius type oxide, the forbidden bandwidth of the catalyst is about 2.7eV, and the catalyst can absorb visible light with the wavelength within 450nm, so that organic pollutants can be catalytically degraded under the irradiation of the visible light, and the utilization efficiency of sunlight is effectively improved. Meanwhile, the raw material resources are rich, the environment-friendly effect is achieved, the stability is good, and the like, so that the method has a wide application prospect.

Currently synthesized Bi₂WO₆The main methods of the method comprise microwave, deposition, hydrothermal method and the like, wherein the hydrothermal solvothermal method is widely used for preparing various nano materials due to the advantages of easy control of crystal growth reaction kinetics, high product crystallinity and the like, and different particle morphologies show different electrochemical properties. Bi synthesized at home and abroad at present₂WO₆Has the problems of complex process, large grain size and inhibition of the photocatalytic activity.

Disclosure of Invention

The invention aims to provide bismuth tungstate (Bi) which has simple process and is easy to control₂WO₆) A hydrothermal synthesis preparation method of nano powder.

The invention adopts the following technical scheme:

a preparation method of bismuth tungstate nano powder is characterized by comprising the following steps:

1) dissolving bismuth nitrate in ethylene glycol to form a bismuth nitrate solution;

2) dissolving sodium tungstate in deionized water to form a sodium tungstate solution;

3) pouring the bismuth nitrate solution obtained in the step 1) into the sodium tungstate solution obtained in the step 2), stirring and transferring to a high-pressure reaction kettle;

4) and (3) sealing the reaction kettle equipped with the high-pressure reaction material, carrying out heat treatment, cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying to obtain the bismuth tungstate nano powder.

Preferably, in the step 1), the concentration of the bismuth nitrate solution is 0.1-0.2 mol/L.

Preferably, the concentration of the sodium tungstate solution in the step 2) is 0.01-0.02 mol/L.

Preferably, in the step 3), the molar ratio of the sodium tungstate to the bismuth nitrate is 1: 1-1: 2.

Preferably, in the step 4), heat treatment is carried out for 14 to 20 hours at the temperature of 120 to 140 ℃.

Preferably, step 4), drying at the temperature of 60-80 ℃ to obtain the bismuth tungstate nano powder.

Bi prepared by the invention₂WO₆The nano powder has good dispersibility and the thickness is not more than 20nm, so the specific surface area of the material can be effectively increased, and the nano powder has higher application value in the aspects of photocatalysis and the like.

The purity of the raw materials of sodium tungstate, potassium bismuth nitrate, the solvent of ethylene glycol, deionized water and absolute ethyl alcohol used in the invention is not lower than that of chemical purity.

By using the Bi of the present invention₂WO₆Preparation method of nanosheet and prepared Bi₂WO₆Good dispersibility and thickness not greater than 20 nm.

The invention takes bismuth nitrate, sodium tungstate and the like as raw materials, controls Bi by regulating and controlling the time and the temperature of hydrothermal treatment by regulating and controlling the quantity proportion of each raw material substance in a mixed solvent₂WO₆Thereby realizing Bi growth process₂WO₆And (4) synthesizing nano powder. The cleaning of the water/solvothermal synthesis product is carried out to remove the excess reactant and obtain pure Bi₂WO₆Nano-sheet powder. Dehydration with absolute ethyl alcohol and drying at a temperature of not higher than 80 ℃ are adopted to obtain Bi with good dispersibility₂WO₆And (3) nano powder.

The method has the advantages of simple process, easy control, no environmental pollution, low cost and easy large-scale production. Prepared Bi₂WO₆Is in the form of granules, and its thickness is not greater than 20 nm. The product has stable quality, high purity and good powder particle dispersibility.

Drawings

FIG. 1 Bi synthesized by the present invention₂WO₆An X-ray diffraction (XRD) pattern of the nanopowder;

FIG. 2 Bi synthesized by the present invention₂WO₆Scanning Electron Microscope (SEM) photographs of the nanopowder.

Detailed Description

The present invention is further illustrated by the following examples.

Example 1

Bi is synthesized according to the following process steps₂WO₆Nano powder:

1) measuring bismuth nitrate by a metering amount, dissolving the bismuth nitrate in ethylene glycol, and adjusting the concentration of the formed bismuth nitrate solution to be: 0.2mol/L (mol per liter).

2) Weighing sodium tungstate to be dissolved in deionized water, and adjusting the concentration of the formed sodium tungstate solution to be: 0.02mol/L (mol per liter).

3) Slowly pouring the solution obtained in the step 1) into the solution obtained in the step 2), adjusting the molar ratio of ammonium chloride to bismuth nitrate to be 1:2, stirring, transferring into a high-pressure reaction kettle, and adjusting 4/5 of the volume of the high-pressure reaction kettle to be the volume of the high-pressure reaction kettle by using deionized water.

4) The reaction kettle with the reaction materials is sealed and heat-treated at 140 ℃ for 20 hours. Then cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying at 60 ℃ to obtain Bi₂WO₆And (3) nano powder.

Bi synthesized in this example₂WO₆The X-ray diffraction (XRD) pattern of the nanopowder is shown in FIG. 1. The Scanning Electron Microscope (SEM) photograph thereof is shown in FIG. 2.

This example synthesizes Bi with a width of not more than 20nm by a water/solvothermal method₂WO₆And (3) nano powder.

Example 2

Bi is synthesized according to the following process steps₂WO₆Nano powder:

1) measuring bismuth nitrate by a metering amount, dissolving the bismuth nitrate in ethylene glycol, and adjusting the concentration of the formed bismuth nitrate solution to be: 0.1 mol/L.

2) Weighing sodium tungstate to be dissolved in deionized water, and adjusting the concentration of the formed sodium tungstate solution to be: 0.01 mol/L.

3) Slowly pouring the solution obtained in the step 1) into the solution obtained in the step 2), adjusting the molar ratio of ammonium chloride to bismuth nitrate to be 1:1, stirring, transferring into a high-pressure reaction kettle, and adjusting 2/3 of the volume of the high-pressure reaction kettle to be the volume of the high-pressure reaction kettle by using deionized water.

4) The reaction kettle with the reaction materials is sealed, and heat treatment is carried out at 120 ℃ for 14 hours. Then cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying at the temperature of 80 ℃ to obtain Bi₂WO₆And (3) nano powder.

Example 3

Bi is synthesized according to the following process steps₂WO₆Nano powder:

1) measuring bismuth nitrate by a metering amount, dissolving the bismuth nitrate in ethylene glycol, and adjusting the concentration of the formed bismuth nitrate solution to be: 0.1 mol/L.

2) Weighing sodium tungstate to be dissolved in deionized water, and adjusting the concentration of the formed sodium tungstate solution to be: 0.01 mol/L.

3) Slowly pouring the solution obtained in the step 1) into the solution obtained in the step 2), adjusting the molar ratio of ammonium chloride to bismuth nitrate to be 1:2, stirring, transferring into a high-pressure reaction kettle, and adjusting 3/4 of the volume of the high-pressure reaction kettle to be the volume of the high-pressure reaction kettle by using deionized water.

4) The reaction kettle with the reaction materials is sealed and heat-treated at 140 ℃ for 20 hours. Then cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying at the temperature of 80 ℃ to obtain Bi₂WO₆And (3) nano powder.

Example 4

Bi is synthesized according to the following process steps₂WO₆Nano powder:

1) measuring bismuth nitrate by a metering amount, dissolving the bismuth nitrate in ethylene glycol, and adjusting the concentration of the formed bismuth nitrate solution to be: 0.15 mol/L.

2) Weighing sodium tungstate to be dissolved in deionized water, and adjusting the concentration of the formed sodium tungstate solution to be: 0.015 mol/L.

3) Slowly pouring the solution obtained in the step 1) into the solution obtained in the step 2), adjusting the molar ratio of ammonium chloride to bismuth nitrate to be 1:1.5, stirring, transferring to a high-pressure reaction kettle, and adjusting the volume of the high-pressure reaction kettle to 2/3 which accounts for the volume of the reaction kettle by using deionized water.

4) The reaction kettle with the reaction materials is sealed, and heat treatment is carried out at 130 ℃ for 18 hours. Then cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying at 70 ℃ to obtain Bi₂WO₆And (3) nano powder.

Example 5

Bi is synthesized according to the following process steps₂WO₆Nano powder:

1) measuring bismuth nitrate by a metering amount, dissolving the bismuth nitrate in ethylene glycol, and adjusting the concentration of the formed bismuth nitrate solution to be: 0.18 mol/L.

2) Weighing sodium tungstate to be dissolved in deionized water, and adjusting the concentration of the formed sodium tungstate solution to be: 0.012 mol/L.

3) Slowly pouring the solution obtained in the step 1) into the solution obtained in the step 2), adjusting the molar ratio of ammonium chloride to bismuth nitrate to be 1:1.3, stirring, transferring to a high-pressure reaction kettle, and adjusting the volume of the high-pressure reaction kettle to 2/3 which accounts for the volume of the reaction kettle by using deionized water.

4) The reaction kettle with the reaction materials is sealed and is thermally treated for 15 hours at 125 ℃. Then cooling to room temperature, filtering, sequentially washing with deionized water and absolute ethyl alcohol, and drying at 65 ℃ to obtain Bi₂WO₆And (3) nano powder.

The invention has simple preparation operation, low cost and strong repeatability, and adopts common raw material reagents. The bismuth tungstate nano powder prepared by the simple hydrothermal method has good dispersibility and the thickness of not more than 20nm, so that Bi can be reduced₂WO₆The particle size of the material effectively increases the specific surface area of the material, is beneficial to subsequent load treatment, and has higher application value in the aspects of photocatalysis and the like.