阅读说明：本技术 一种用于降解有机废水的Sb-SnO2/SnS2纳米催化剂及其制备方法和应用 (Sb-SnO for degrading organic wastewater2/SnS2Nano catalyst and preparation method and application thereof ) 是由 陈阿青 梁轻 孔哲 于 2021-08-26 设计创作，主要内容包括：本发明公开了一种用于降解有机废水的Sb-SnO-(2)/SnS-(2)纳米催化剂及其制备方法和应用。以硫脲和四氯化锡为原料,通过水热法合成得到二维片层的SnS-(2)纳米催化剂,之后真空烘干得到黄色粉末状。再将得到的SnS-(2)纳米催化剂分散在含有四氯化锡和三氯化锑的水溶液中,再次通过水热工艺得到复合型的Sb-SnO-(2)/SnS-(2)异质结纳米颗粒。该催化剂具有球状的纳米花结构,能够实现光催化剂对紫外光、可见光到近红外光的有效吸收,增强了光催化剂利用太阳光降解有机废水的能力。(The invention discloses Sb-SnO for degrading organic wastewater 2 /SnS 2 A nano catalyst and a preparation method and application thereof. Synthesizing two-dimensional lamellar SnS by taking thiourea and stannic chloride as raw materials through a hydrothermal method 2 And (4) drying the nano catalyst in vacuum to obtain yellow powder. Then the obtained SnS 2 Dispersing the nano catalyst in an aqueous solution containing stannic chloride and antimony trichloride, and obtaining the composite Sb-SnO through a hydrothermal process 2 /SnS 2 Heterojunction nanoparticles. The photocatalyst has a spherical nanometer flower structure, and can realize ultraviolet light and visible light to near redThe effective absorption of external light enhances the capability of the photocatalyst in degrading organic wastewater by utilizing sunlight.)

1. Sb-SnO₂/SnS₂The preparation method of the heterojunction nano catalyst is characterized by comprising the following steps:

s1, taking thiourea and stannic chloride as raw materials, adding deionized water, dissolving and stirring to obtain an aqueous solution of thiourea and stannic chloride;

s2, synthesizing SnS of two-dimensional lamellar by aqueous solution of thiourea and stannic chloride through hydrothermal method₂A nano-catalyst;

s3 SnS for the two-dimensional slice layer₂Drying the nano catalyst in vacuum to obtain SnS₂The nano catalyst is yellow powder;

s4, SnS₂Dispersing the nano catalyst in yellow powder in an aqueous solution containing stannic chloride and antimony trichloride, adjusting the pH to 5-6, and obtaining the nano catalyst by a hydrothermal processTo composite Sb-SnO₂/SnS₂A heterojunction nanoparticle; wherein the mass ratio of stannic chloride to antimony trichloride is 97: 10-3, and SnS₂The mass ratio of the nano catalyst particles to the aqueous solution of tin tetrachloride and antimony trichloride is 0.8-2: 100.

2. an Sb-SnO according to claim 1₂/SnS₂The preparation method of the heterojunction nano catalyst is characterized in that in the step S1, the mass ratio of thiourea to tin tetrachloride is 1: 2-3.

3. An Sb-SnO according to claim 1₂/SnS₂The preparation method of the heterojunction nano catalyst is characterized in that in the step S1, the reaction temperature is 20-30 ℃, and the stirring time is 1-3 hours.

4. An Sb-SnO according to claim 1 or 2₂/SnS₂The preparation method of the heterojunction nano catalyst is characterized in that in the step S1, the pH value of an aqueous solution of thiourea and stannic chloride is 5-6.

5. An Sb-SnO according to claim 1₂/SnS₂The preparation method of the heterojunction nano-catalyst is characterized in that SnS of the two-dimensional lamellar in the step S2₂The hydrothermal synthesis temperature of the nano catalyst is 160-180 ℃; the synthesis time is 16-18 hours.

6. An Sb-SnO according to claim 1₂/SnS₂The preparation method of the heterojunction nano-catalyst is characterized in that SnS of the two-dimensional lamellar in the step S3₂The vacuum drying temperature of the nano catalyst is 60-70 ℃.

7. An Sb-SnO according to claim 1₂/SnS₂The preparation method of the heterojunction nano-catalyst is characterized in that hydrochloric acid is adopted to adjust the pH value to 5-6 in the step S4.

8. As claimed in claim 1Or 5 said Sb-SnO₂/SnS₂The preparation method of the heterojunction nano-catalyst is characterized in that the composite Sb-SnO in the step S4₂/SnS₂The hydro-thermal synthesis temperature of the heterojunction nano particles is 160-180 ℃; the hydrothermal synthesis time is 16-18 hours.

9. Sb-SnO₂/SnS₂Heterojunction nanocatalyst, obtainable by the process according to any of claims 1 to 8, characterized in that it is obtained from SnS of a two-dimensional nanosheet₂Nano catalyst and Sb doped SnO₂The nano particles form a nano flower junction Sb-SnO with a spherical shape₂/SnS₂A heterojunction composite nano catalyst.

10. An Sb-SnO according to claim 9₂/SnS₂Application of the heterojunction nano catalyst in degrading organic wastewater.

Technical Field

The invention belongs to the technical field of photocatalysts for degrading organic pollutants by using sunlight, and particularly relates to Sb-SnO for degrading organic wastewater₂/SnS₂A nano catalyst and a preparation method and application thereof.

Background

The current treatment process of industrial wastewater adopts traditional biochemical bacteria to degrade organic matters, ammonia nitrogen and total nitrogen in the wastewater. However, with the rapid development of modern industry, the components of industrial wastewater become more and more complex, and the biological toxicity of the wastewater becomes higher and higher; especially the wastewater of chemical industry and medicine manufacturing, has the characteristics of high COD, high ammonia nitrogen, high salinity and the like. Biochemical bacteria are difficult to survive in the high-concentration wastewater and cannot degrade the high-concentration wastewater. Other added oxidants, such as hydrogen peroxide, sodium hypochlorite and other advanced oxidation processes can bring secondary pollution in the treatment process. The photocatalyst can generate substances with strong oxidation, hydroxyl radicals and the like by utilizing solar energy. E.g. based on TiO₂The photocatalyst of (3) can decompose organic substances. However, these photocatalysts can only use ultraviolet light in a short wavelength band in sunlight, and the utilization rate of the sunlight is low, so that the efficiency of decomposing organic substances is low. Aiming at the defect, the preparation method is carried out by adding TiO₂Doping to enhance TiO₂Absorption of visible light, as reported in the patent (CN 112774671A) for example, ruthenium doped TiO₂The absorption of visible light is enhanced. However, ruthenium doped TiO₂The absorption of light above 400nm is relatively weak, full spectrum absorption is not realized, and the application of the current photocatalysis treatment of industrial wastewater cannot be met. Therefore, it is important to develop a catalyst capable of utilizing sunlight in photocatalytic degradation of organic wastewater.

Disclosure of Invention

An object of the present invention is to provide Sb-SnO against the disadvantages of the prior art₂/SnS₂A preparation method of a heterojunction nano catalyst. The photocatalyst can absorb ultraviolet light, visible light and near infrared light in the solar spectrum, greatly improves the capability of the photocatalyst in catalyzing and degrading organic matters in wastewater by utilizing sunlight, overcomes the defect of the photocatalyst in utilizing the sunlight, and realizes good photoelectrocatalysis effect even under weak light.

The invention is realized by the following technical scheme:

the invention relates to Sb-SnO₂/SnS₂A method of heterojunction nanocatalyst, comprising the steps of:

s1, taking thiourea and stannic chloride as raw materials, adding deionized water, dissolving and stirring to obtain an aqueous solution of thiourea and stannic chloride;

s2, synthesizing SnS of two-dimensional lamellar by aqueous solution of thiourea and stannic chloride through hydrothermal method₂A nano-catalyst;

s3 SnS for the two-dimensional slice layer₂Drying the nano catalyst in vacuum to obtain SnS₂The nano catalyst is yellow powder;

s4, SnS₂Dispersing the nano catalyst in yellow powder in an aqueous solution containing stannic chloride and antimony trichloride, adjusting the pH to 5-6, and obtaining the composite Sb-SnO through a hydrothermal process₂/SnS₂A heterojunction nanoparticle; wherein the mass ratio of the stannic chloride to the antimony trichloride is 97: 10-3, which ensures that the product Sb-SnO₂/SnS₂The heterojunction nanoparticles are black; SnS₂The mass ratio of the nano catalyst particles to the aqueous solution of tin tetrachloride and antimony trichloride is 0.8-2: 100, which ensures Sb-SnO₂/SnS₂The heterojunction nano catalyst is spherical nano flower-shaped nano particles;

further, the mass ratio of thiourea to tin tetrachloride in step S1 is 1: 2-3;

further, in the step S1, the reaction temperature is 20-30 ℃, and the stirring time is 1-3 hours;

further, in the step S1, the pH value of the aqueous solution of thiourea and tin tetrachloride is 5-6;

further, the SnS of the two-dimensional slice in step S2₂The hydrothermal synthesis temperature of the nano catalyst is 160-180 ℃;

further, the SnS of the two-dimensional slice in step S2₂The hydrothermal synthesis time of the nano catalyst is 16-18 hours;

further, the SnS of the two-dimensional slice in step S3₂The vacuum drying temperature of the nano catalyst is 60-70 ℃;

further, in the step S4, hydrochloric acid is adopted to adjust the pH value to 5-6, so that antimony trichloride is completely dissolved in water, and the solution is clear and uniform;

further, Sb-SnO of composite type in step S4₂/SnS₂The hydro-thermal synthesis temperature of the heterojunction nano particles is 160-180 ℃;

further, Sb-SnO of composite type in step S4₂/SnS₂The hydrothermal synthesis time of the heterojunction nano-particles is 16-18 hours.

Another object of the present invention is to provide a Sb-SnO₂/SnS₂The heterojunction nano catalyst is prepared by adopting the method. The catalyst is a composite nano catalyst formed by a two-dimensional nanosheet layer of SnS2 nano catalyst and Sb-doped SnO2 nano particles, and has a spherical nano flower junction Sb-SnO2/SnS2 heterojunction. The nano-catalyst has a spherical nano-flower structure, can realize effective absorption of the photocatalyst to ultraviolet light, visible light and near infrared light, can realize good photoelectric property under weak light, and enhances the capability of the photocatalyst in degrading organic wastewater by utilizing sunlight.

It is still another object of the present invention to provide Sb-SnO₂/SnS₂Application of the heterojunction nano catalyst in degrading organic wastewater.

The invention has the following beneficial effects:

Sb-SnO of the present invention₂/SnS₂The heterojunction nano catalyst particles can keep almost equal absorbance of visible light in a full spectrum, absorb the visible light, and realize good photoelectrocatalysis effect under weak light, thereby effectively degrading organic matters in wastewater and removing COD.

Drawings

FIG. 1 is Sb-SnO in examples of the present invention₂/SnS₂Scanning electron photographs of heterojunction nanoparticles;

FIG. 2 is Sb-SnO in examples of the present invention₂/SnS₂An XRD pattern of the heterojunction nanoparticles;

FIG. 3 is Sb-SnO in examples of the present invention₂/SnS₂Visible light absorption spectrum of the heterojunction nanoparticles.

FIG. 4 shows Sb-SnO in examples of the present invention₂/SnS₂And (3) a heterojunction nano-particle effect diagram for removing COD in the wastewater.

Detailed Description

The present invention is further analyzed with reference to the following specific examples.

Examples 1, 1,

1. 1.75g SnCl is weighed by an electronic balance₄·5H₂O and 0.75g thiourea, dissolving the two chemical substances into 60mL deionized water, continuously stirring for 70min at a constant temperature of 25 ℃ by using a magnetic heating stirrer to fully disperse the solution to obtain a uniform transparent solution, adjusting the pH value of the solution to 5.0, and then transferring the solution into a stainless steel reaction kettle lining with the capacity of 80 mL. And (3) putting the screwed and sealed stainless steel reaction kettle into a constant-temperature drying box, adjusting the temperature of the drying box to be below 180 ℃, and keeping the constant temperature for 16 hours. And after the reaction kettle is heated, taking out the reaction kettle, cooling to room temperature, sucking out supernatant liquid by using a dropper, pouring the nanoparticles synthesized in the lining into a beaker, and repeatedly washing the beaker with deionized water for 3 times. Washing with deionized water, drying in vacuum drying oven at 60 deg.C for 24 hr, and taking out the obtained dry SnS₂And (3) obtaining the product.

2. Weighing 1.80g SnCl by using an electronic balance₄·5H₂Dissolving two chemical substances of O and 0.06g of antimony trichloride into 60mL of deionized water, adjusting the pH of the solution to 5.0 by hydrochloric acid, continuously stirring for 30min at constant temperature of 25 ℃ by using a magnetic heating stirrer to fully disperse the solution to obtain a uniform and transparent solution, and then weighing the SnS prepared in the step 1₂0.5g, and stirring uniformly; finally, the solution was transferred to a stainless steel reactor liner having a capacity of 80 ml. And (3) putting the screwed and sealed stainless steel reaction kettle into a constant-temperature drying box, adjusting the temperature of the drying box to be below 180 ℃, and keeping the constant temperature for 16 hours. And after the reaction kettle is heated, taking out the reaction kettle, cooling to room temperature, sucking out supernatant liquid by using a dropper, pouring the synthesized substances in the liner into a beaker, and repeatedly washing the beaker with deionized water for 3 times. After the deionized water washing, the mixture is placed into a vacuum drying oven and dried for 24 hours at 50 ℃, and then the obtained dried product is taken out and ground for storage.

FIG. 1 is Sb-SnO in examples of the present invention₂/SnS₂Scanning electron photographs of heterojunction nanoparticles;

FIG. 2 is Sb-SnO in examples of the present invention₂/SnS₂An XRD pattern of the heterojunction nanoparticles;

FIG. 3 is Sb-SnO in examples of the present invention₂/SnS₂Visible light absorption spectrum of the heterojunction nanoparticles.

Examples 2,

1. 2.00g SnCl is weighed by an electronic balance₄·5H₂O and 0.85g thiourea, dissolving the two chemical substances into 60mL deionized water, continuously stirring for 70min at a constant temperature of 25 ℃ by using a magnetic heating stirrer to fully disperse the solution to obtain a uniform transparent solution, adjusting the pH value of the solution to be 6.0, and then transferring the solution into a stainless steel reaction kettle lining with the capacity of 80 mL. And (3) putting the screwed and sealed stainless steel reaction kettle into a constant-temperature drying box, adjusting the temperature of the drying box to be below 160 ℃, and keeping the constant temperature for 16 hours. And after the reaction kettle is heated, taking out the reaction kettle, cooling to room temperature, sucking out supernatant liquid by using a dropper, pouring the nanoparticles synthesized in the lining into a beaker, and repeatedly washing the beaker with deionized water for 3 times. Washing with deionized water, drying in vacuum drying oven at 70 deg.C for 24 hr, and taking out the obtained dry SnS₂And (3) obtaining the product.

2. 2.00g SnCl is weighed by an electronic balance₄·5H₂Dissolving two chemical substances of O and 0.08g of antimony trichloride into 60mL of deionized water, adjusting the pH of the solution to 5.0 by using hydrochloric acid, continuously stirring for 30min at constant temperature of 25 ℃ by using a magnetic heating stirrer to fully disperse the solution to obtain a uniform and transparent solution, and then weighing the SnS prepared in the step 1₂0.5g, and stirred well, and finally, the solution was transferred to a stainless steel reactor liner having a capacity of 80 ml. And (3) putting the screwed and sealed stainless steel reaction kettle into a constant-temperature drying box, adjusting the temperature of the drying box to be below 180 ℃, and keeping the constant temperature for 16 hours. And after the reaction kettle is heated, taking out the reaction kettle, cooling to room temperature, sucking out supernatant liquid by using a dropper, pouring the synthesized substances in the liner into a beaker, and repeatedly washing the beaker with deionized water for 3 times. Washing with deionized water, drying in vacuum drying oven at 50 deg.C for 24 hr, and taking outThe dried product was stored after grinding.

Examples 3,

1. Weighing 1.80g SnCl by using an electronic balance₄·5H₂Dissolving two chemical substances into 60mL of deionized water, continuously stirring for 80min at constant temperature of 30 ℃ by using a magnetic heating stirrer to fully disperse the solution to obtain a uniform transparent solution, adjusting the pH value of the solution to 6.0, and then transferring the solution to a stainless steel reaction kettle lining with the capacity of 80 mL. And (3) putting the screwed and sealed stainless steel reaction kettle into a constant-temperature drying box, adjusting the temperature of the drying box to be 170 ℃, and keeping the constant temperature for 16 hours. And after the reaction kettle is heated, taking out the reaction kettle, cooling to room temperature, sucking out supernatant liquid by using a dropper, pouring the nanoparticles synthesized in the lining into a beaker, and repeatedly washing the beaker with deionized water for 3 times. Washing with deionized water, drying in vacuum drying oven at 60 deg.C for 24 hr, and taking out the obtained dry SnS₂And (3) obtaining the product.

2. 2.00g SnCl is weighed by an electronic balance₄·5H₂Dissolving two chemical substances of O and 0.10g of antimony trichloride into 60mL of deionized water, adjusting the pH of the solution to 5.0 by hydrochloric acid, continuously stirring for 30min at constant temperature of 25 ℃ by using a magnetic heating stirrer to fully disperse the solution to obtain a uniform and transparent solution, and then weighing the SnS prepared in the step 1₂1.0g, and stirred well, and finally, the solution was transferred to a stainless steel reactor liner having a capacity of 80 ml. And (3) putting the screwed and sealed stainless steel reaction kettle into a constant-temperature drying box, adjusting the temperature of the drying box to be below 160 ℃, and keeping the constant temperature for 18 hours. And after the reaction kettle is heated, taking out the reaction kettle, cooling to room temperature, sucking out supernatant liquid by using a dropper, pouring the synthesized substances in the liner into a beaker, and repeatedly washing the beaker with deionized water for 3 times. After the deionized water washing, the mixture is placed into a vacuum drying oven and dried for 24 hours at 50 ℃, and then the obtained dried product is taken out and ground for storage.

Application example:

(1) 500mL of phenol solution with the COD content of 1260mg/L is prepared to simulate organic wastewater.

(2) 50mg of Sb-SnO in the above examples₂/SnS₂Heterogeneous natureDispersing the nanoparticles into the simulated organic wastewater solution prepared in the step 1, and recording as an experimental group 1. For comparison, 50mg of pure SnS was also set₂And (3) dispersing the lamellar nano particles into the simulated organic wastewater solution with the same parameters and prepared in the step (1), and marking as a control group 1.

(3) The solutions of the experimental group 1 and the control group 1 were placed under illumination at an intensity of 1000W/m²Under the light of the solar simulator, stirring is carried out continuously, and sampling is carried out every 30 minutes to detect the COD content. After 120 minutes, Sb-SnO was dispersed₂/SnS₂The COD content in the phenol solution (experimental group 1) of the heterojunction nano-particles is only about 300 mg/L; dispersed pure SnS₂The COD content of the phenol solution of lamellar nanoparticles (control 1) was 900 mg/L.

FIG. 4 shows Sb-SnO in examples of the present invention₂/SnS₂And (3) a heterojunction nano-particle effect diagram for removing COD in the wastewater.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.