阅读说明：本技术 一种二硫化锡/金复合催化剂及其制备方法和应用 (Tin disulfide/gold composite catalyst and preparation method and application thereof ) 是由 李炳生 付荣鹏 邵长路 王月飞 马剑钢 于 2020-08-27 设计创作，主要内容包括：本发明涉及光催化剂技术领域,本发明提供了一种二硫化锡/金复合催化剂,包括纳米二硫化锡和修饰于所述纳米二硫化锡表面的纳米金。本发明选用在可见光区具有强烈的局域表面等离子体共振特性的纳米金对纳米二硫化锡表面进行修饰,对可见光能够产生强烈的散射和吸收作用,提高了二硫化锡/金复合催化剂对可见光利用效率,从而提升了以二硫化锡为主要催化成分复合催化剂的催化能力。实施例结果表明,利用本发明提供的催化剂对有机物进行降解时,15min内,可将甲基橙溶液中的甲基橙的浓度降解至原浓度的10％以下,对有机物的降解能力达到90％以上。(The invention relates to the technical field of photocatalysts, and provides a tin disulfide/gold composite catalyst which comprises nano tin disulfide and nano gold modified on the surface of the nano tin disulfide. According to the invention, nanogold with strong local surface plasma resonance characteristics in a visible light region is selected to modify the surface of the nano tin disulfide, so that strong scattering and absorption effects can be generated on visible light, the utilization efficiency of the tin disulfide/gold composite catalyst on the visible light is improved, and the catalytic capability of the composite catalyst taking the tin disulfide as a main catalytic component is improved. The results of the examples show that when the catalyst provided by the invention is used for degrading organic matters, the concentration of methyl orange in a methyl orange solution can be degraded to be less than 10% of the original concentration within 15min, and the degradation capability of the catalyst on the organic matters can reach more than 90%.)

1. A tin disulfide/gold composite catalyst comprises nano tin disulfide and nano gold modified on the surface of the nano tin disulfide.

2. The tin disulfide/gold composite catalyst according to claim 1, wherein the mass ratio of the nano tin disulfide to the nano gold is 10: 1-5: 1.

3. The tin disulfide/gold composite catalyst according to claim 1 or 2, wherein the nano tin disulfide has a sheet-like truncated-angle dodecahedron structure; the particle size of the nano tin disulfide is 100-200 nm, and the particle size of the nano gold is 10-40 nm.

4. A method for preparing a tin disulfide/gold composite catalyst as set forth in any one of claims 1 to 3, comprising the steps of:

and mixing the nano tin disulfide, the nano gold colloid and water, and drying to obtain the tin disulfide/gold composite catalyst.

5. The preparation method of the tin disulfide/gold composite catalyst according to claim 4, wherein the preparation method of the nano tin disulfide comprises the following steps:

mixing tin salt, thioacetamide, water and acid corresponding to the anion of the tin salt, and carrying out hydrothermal reaction to obtain the nano tin disulfide.

6. The method of claim 5, wherein the tin salt comprises at least one of tin tetrachloride, tin methane sulfonate, and tin ethane sulfonate.

7. The preparation method of the tin disulfide/gold composite catalyst according to claim 5, wherein the temperature of the hydrothermal reaction is 120-200 ℃ and the time of the hydrothermal reaction is 10-30 h.

8. The method for preparing the tin disulfide/gold composite catalyst according to claim 4, wherein the method for preparing the nano gold colloid comprises the following steps:

mixing chloroauric acid, water and a reducing agent, and carrying out reduction reaction to obtain the nano gold colloid.

9. The method of claim 8, wherein the reducing agent comprises at least one of sodium borohydride, ascorbic acid, and sodium citrate.

10. Use of the tin disulfide/gold composite catalyst according to any one of claims 1 to 3 or the tin disulfide/gold composite catalyst prepared by the preparation method according to any one of claims 4 to 9 in organic matter degradation.

Technical Field

The invention relates to the technical field of photocatalysis, in particular to a tin disulfide/gold composite catalyst and a preparation method and application thereof.

Background

The photocatalytic technology has wide application in degrading pollutants, and the principle is based on the oxidation-reduction capacity of the catalyst under the condition of illumination, so that the purposes of purifying pollutants, synthesizing and converting substances and the like can be achieved, and the self property of the catalyst plays a decisive role in degrading organic matters.

The composite catalyst with tin disulfide as the main catalytic component has the advantages that the separation efficiency of photoproduction electrons and holes is improved through interfacial charge transfer of all components, so that the composite material with tin disulfide as the main catalytic component has wide application in the aspect of pollutant degradation.

Disclosure of Invention

In view of the above, the invention aims to provide a tin disulfide/gold composite catalyst, and a preparation method and an application thereof, when the catalyst provided by the invention is used for degrading organic matters, the concentration of methyl orange in a methyl orange solution can be degraded to be less than 10% of the original concentration within 15min, and the degradation capability of the catalyst on the organic matters can reach more than 90%.

In order to achieve the above object, the present invention provides the following technical solutions:

a tin disulfide/gold composite catalyst comprises nano tin disulfide and nano gold modified on the surface of the nano tin disulfide.

Preferably, the mass ratio of the nano tin disulfide to the nano gold is 10: 1-5: 1.

Preferably, the nano tin disulfide has a sheet-shaped truncated-angle dodecahedron structure; the particle size of the nano tin disulfide is 100-200 nm, and the particle size of the nano gold is 10-40 nm.

The invention also provides a preparation method of the tin disulfide/gold composite catalyst, which comprises the following steps:

and mixing the nano tin disulfide, the nano gold colloid and water, and drying to obtain the tin disulfide/gold composite catalyst.

Preferably, the preparation method of the nano tin disulfide comprises the following steps:

mixing tin salt, thioacetamide, water and acid corresponding to the anion of the tin salt, and carrying out hydrothermal reaction to obtain the nano tin disulfide.

Preferably, the tin salt includes at least one of tin tetrachloride, tin methane sulfonate, and tin ethane sulfonate.

Preferably, the temperature of the hydrothermal reaction is 120-200 ℃, and the time of the hydrothermal reaction is 10-30 h.

Preferably, the preparation method of the nanogold colloid comprises the following steps:

mixing chloroauric acid, water and a reducing agent, and carrying out reduction reaction to obtain the nano gold colloid.

Preferably, the reducing agent includes at least one of sodium borohydride, ascorbic acid, and sodium citrate.

The invention also provides the application of the tin disulfide/gold composite catalyst or the tin disulfide/gold composite catalyst prepared by the preparation method according to the technical scheme in degrading organic matters.

The invention provides a tin disulfide/gold composite catalyst, which comprises nano tin disulfide and nano gold modified on the surface of the nano tin disulfide. According to the invention, nanogold with strong local surface plasma resonance characteristics in a visible light region is selected to modify the surface of the nano tin disulfide, so that strong scattering and absorption effects can be generated on visible light, the utilization efficiency of the tin disulfide/gold composite catalyst on the visible light is improved, and the catalytic capability of the composite catalyst taking tin disulfide as a main catalytic component is improved. The results of the examples show that when the catalyst provided by the invention is used for degrading organic matters, the concentration of methyl orange in a methyl orange solution can be degraded to be less than 10% of the original concentration within 15min, and the degradation capability of the catalyst on the organic matters can reach more than 90%.

Drawings

FIG. 1 is a scanning electron micrograph of nano-tin disulfide prepared in example 2;

FIG. 2 is a TEM photograph of the composite Sn/Au disulfide catalyst prepared in example 2;

FIG. 3 is an X-ray diffraction pattern of nano-tin disulfide prepared in example 2;

FIG. 4 is an absorption spectrum of the nano-sized tin disulfide and tin disulfide/gold composite catalyst prepared in example 2;

FIG. 5 is a degradation curve of methyl orange degraded by the nano-tin disulfide prepared in example 2 and the tin disulfide/gold composite catalyst prepared in examples 1 to 3.

Detailed Description

The invention provides a tin disulfide/gold composite catalyst, which comprises nano tin disulfide and nano gold modified on the surface of the nano tin disulfide.

In the invention, the mass ratio of the nano tin disulfide to the nano gold is preferably 10: 1-5: 1. The invention limits the mass ratio of the nano tin disulfide to the nano gold within the range, and the catalyst has higher catalytic capability.

In the present invention, the nano tin disulfide preferably has a sheet-like truncated-angle dodecahedron structure. In the invention, the particle size of the nano tin disulfide is preferably 80-300 nm, and more preferably 100-200 nm. The particle size of the nano gold is preferably 10-40 nm. The invention selects the nano tin disulfide with the structure, and limits the particle size of the nano tin disulfide, nano gold and the tin disulfide/gold composite catalyst within the range, and the catalyst has higher catalytic capability.

According to the tin disulfide/gold composite catalyst provided by the invention, the surface of the nano tin disulfide is modified by selecting the nano gold with strong local surface plasma resonance characteristics in a visible light area, so that strong scattering and absorption effects can be generated on visible light, the utilization efficiency of the tin disulfide/gold composite catalyst on the visible light is improved, and the catalytic capability of the composite catalyst taking the tin disulfide as a main catalytic component is improved.

The invention also provides a preparation method of the tin disulfide/gold composite catalyst, which comprises the following steps:

and mixing the nano tin disulfide, the nano gold colloid and water, and drying to obtain the tin disulfide/gold composite catalyst.

In the present invention, the water used is preferably deionized water unless otherwise specified.

In the present invention, the preparation method of the nano tin disulfide preferably comprises the following steps:

mixing tin salt, thioacetamide, water and acid corresponding to the anion of the tin salt, and carrying out hydrothermal reaction to obtain the nano tin disulfide.

In the present invention, the tin salt preferably includes at least one of tin tetrachloride, tin methane sulfonate, and tin ethane sulfonate, and more preferably tin tetrachloride. The invention selects stannic chloride as tin salt, the property of the stannic chloride in water is relatively stable, and the prepared stannic disulfide/gold composite catalyst has better performance.

In the present invention, the acid is preferably hydrochloric acid, methanesulfonic acid and ethanesulfonic acid, and more preferably hydrochloric acid. According to the invention, the acid corresponding to the anion of the tin salt is added in the preparation of the nano tin disulfide, so that the added tin salt can be prevented from hydrolyzing, and the catalytic capability of the finally prepared tin disulfide/gold composite catalyst is improved. According to the invention, tin tetrachloride and hydrochloric acid are preferably selected to be matched for use, and the prepared nano tin disulfide has a flaky truncated-angle dodecahedron structure, so that the catalytic capability of the tin disulfide/gold composite catalyst can be improved.

In the invention, the mass ratio of the tin salt to the thioacetamide is preferably (1-3): 1, more preferably 2: 1. in the invention, the total concentration of the tin salt and thioacetamide in the solution formed by mixing the tin salt, thioacetamide, water and the acid corresponding to the anion of the tin salt is preferably 45-75 g/L. The tin salt and thioacetamide with the above dosage are selected, and the finally prepared tin disulfide/gold composite catalyst has high catalytic capability.

In the present invention, the concentration of an acid in a solution formed by mixing the tin salt, thioacetamide, water and an acid corresponding to an anion of the tin salt is preferably 1 to 3mol/L, and more preferably 2 mol/L. In the invention, the grown nanometer particles have irregular shapes due to too low concentration of the acid, crystal faces for catalysis cannot be exposed, and the hydrothermal reaction kettle is seriously corroded due to too high concentration.

The amount of water used in the present invention is not particularly limited, and the total concentration of the tin salt and thioacetamide in the mixed solution and the concentration of the acid solution may be satisfied.

In the invention, the temperature of the hydrothermal reaction is 120-200 ℃, and more preferably 140-160 ℃. In the invention, the time of the hydrothermal reaction is preferably 10-14 h, and more preferably 12 h. The invention selects the temperature and the time for hydrothermal reaction, which is beneficial to the full performance of the hydrothermal reaction.

After the hydrothermal reaction is finished, the product of the hydrothermal reaction is preferably sequentially filtered, washed and dried to obtain the nano tin disulfide. The washing operation is not specially specified, and impurities on the tin disulfide solid precipitate are cleaned. In the present invention, the drying temperature is preferably 60 ℃ to 100 ℃, and more preferably 80 ℃; the drying time is preferably 10-14 h, and more preferably 12 h. The drying mode is not specially specified, and the moisture on the tin disulfide solid precipitate is removed.

The nano tin disulfide prepared by the method has better catalytic capability.

The nano gold colloid is used as a raw material for preparing the tin disulfide/gold composite catalyst, so that the combination capacity of tin disulfide and gold can be improved, the charge transfer between tin disulfide and gold interfaces is enhanced, the separation efficiency of photoproduction electrons and cavities is improved, and the catalytic capacity of the tin disulfide/gold composite catalyst is improved.

In the present invention, the preparation method of the nanogold colloid preferably comprises the following steps:

mixing chloroauric acid, water and a reducing agent, and carrying out reduction reaction to obtain the nano gold colloid.

In the present invention, the reducing agent preferably includes at least one of sodium borohydride, ascorbic acid, and sodium citrate, and more preferably sodium borohydride. In the present invention, the sodium borohydride is preferably sodium borohydride. According to the method, sodium borohydride is selected as a reducing agent, the decomposition of the sodium borohydride can be avoided at low temperature, the reducing capability of the sodium borohydride is improved, the sodium borohydride is used as the reducing agent, the local surface plasma resonance characteristic of the finally prepared nano gold colloid is more remarkable, and the finally prepared tin disulfide/gold composite catalyst is better in catalytic performance.

In the present invention, the chloroauric acid is preferably added in the form of a chloroauric acid solution. In the invention, the concentration of the chloroauric acid solution is preferably 8-12 mmol/L, and more preferably 10 mmol/L. According to the invention, the chloroauric acid solution with the concentration range is adopted, the local surface plasma resonance characteristic of the finally prepared nano gold colloid is more obvious, and the finally prepared tin disulfide/gold composite catalyst has better catalytic performance.

In the invention, the volume ratio of the chloroauric acid solution to water is preferably (0.5-4): 10, and more preferably (1-3): 10. The chloroauric acid is added in a solution form, and the using amount of water is controlled within the range, so that the reaction is prevented from being too violent, and the safety of an experiment is improved.

In the present invention, the sodium borohydride is preferably added in the form of a sodium borohydride solution. The method adopts the adding mode of the sodium borohydride solution, avoids violent reaction, improves the operation safety, obtains more uniform nano gold colloidal particles, and finally prepares the tin disulfide/gold composite catalyst with better catalytic performance. In the invention, the concentration of the sodium borohydride solution is preferably 6-12 mmol/L, and more preferably 8-10 mmol/L. In the invention, the volume ratio of the chloroauric acid solution to the sodium borohydride solution is preferably (0.5-4): 2, more preferably (1-3): 2. the invention controls the dosage of the chloroauric acid and the sodium borohydride within the range, and can realize the full reaction of the chloroauric acid.

After the reduction reaction is finished, the product of the reduction reaction is preferably subjected to standing and centrifugation to obtain the nano gold colloid.

In the present invention, the standing is preferably performed at room temperature. In the invention, the standing time is preferably 5-14 h, and more preferably 12 h. According to the invention, the nano gold colloid is kept stand at room temperature, so that the strong scattering and absorption effects of nano gold in the tin disulfide/gold composite catalyst prepared from the nano gold colloid on visible light can be improved, and the catalytic capability of the tin disulfide/gold composite catalyst is improved.

The operation of the centrifugation is not specially specified, and the centrifugation operation known to those skilled in the art is adopted to remove water in the nano gold colloid and impurities dissolved in the water. According to the invention, impurities in the nano gold colloid are removed in a centrifugal mode, so that the influence of the impurities on the scattering and absorption of the nano gold colloid on visible light can be avoided, and the catalytic capability of the tin disulfide/gold composite catalyst is improved.

After the nano tin disulfide and the nano gold colloid are obtained, the nano tin disulfide, the nano gold colloid and water are mixed and dried to obtain the tin disulfide/gold composite catalyst.

The invention preferably mixes the nano tin disulfide and water first and then mixes the nano tin disulfide and the nano gold colloid. The invention selects the mixing sequence, is favorable for fully realizing the modification of the nano gold colloid on the surface of the nano tin disulfide and improving the catalytic capability of the tin disulfide/gold composite catalyst.

In the invention, the volume ratio of the mass of the tin disulfide to the volume of water is preferably (3-6) mg/mL, and more preferably 5 mg/mL. In the invention, the volume of the nano gold colloid and the mass ratio of the nano tin disulfide are preferably (0.5-1.5) mL/mg. According to the invention, the usage amounts of the tin disulfide, the nano gold colloid and the water are controlled within the above range, and the finally prepared tin disulfide/gold composite catalyst has higher catalytic capability.

In the present invention, the temperature for the drying is preferably 50 to 80 ℃, more preferably 60 ℃. In the invention, the drying time is preferably 10-14 h, and more preferably 12 h. The invention adopts the temperature and the time for drying, on one hand, the moisture on the tin disulfide/gold composite catalyst can be completely removed, on the other hand, the compounding of the nano tin disulfide and the nano gold colloid can be realized, and the obtained tin disulfide/gold composite catalyst has higher catalytic performance.

The invention also provides the application of the tin disulfide/gold composite catalyst or the tin disulfide/gold composite catalyst prepared by the preparation method according to the technical scheme in degrading organic matters.

In the present invention, the organic material preferably includes at least one of methyl orange, methyl blue, and rhodamine, and more preferably methyl orange. The catalyst provided by the invention has higher catalytic capability on methyl orange. In the invention, the concentration of the organic matter is preferably 10-30 mg/L, and more preferably 15-25 mg/L. In the present invention, the degradation of the organic matter is preferably performed under visible light. The photocatalyst prepared by the invention has good response to visible light, and can directly degrade organic matters by using the visible light.

According to the tin disulfide/gold composite catalyst provided by the invention, the surface of the nano tin disulfide is modified by selecting the nano gold with strong local surface plasma resonance characteristics in a visible light region, so that strong scattering and absorption effects can be generated on visible light, the utilization efficiency of the tin disulfide/gold composite catalyst on the visible light is improved, and the catalytic capability of the composite catalyst taking the tin disulfide as a main catalytic component is improved. The results of the examples show that when the catalyst provided by the invention is used for degrading organic matters, the concentration of methyl orange in a methyl orange solution can be degraded to be less than 10% of the original concentration within 15min, and the degradation capability of the catalyst on the organic matters can reach more than 90%.

The tin disulfide/gold composite catalyst, the preparation method and the application thereof provided by the present invention are described in detail with reference to the following examples, but they should not be construed as limiting the scope of the present invention.