阅读说明：本技术 一种硼改性光催化材料及其制备方法 (Boron modified photocatalytic material and preparation method thereof ) 是由 陆红阳 姚登鹏 李中毅 张兴旺 于 2021-01-11 设计创作，主要内容包括：本发明一种硼改性光催化材料及其制备方法,首先通过水热反应制备得到纳米CdS空心球,然后通过水热、煅烧制备得到硼改性的WO-3/TiO-2/CdS光催化材料,通过利用纳米CdS空心球、海胆状WO-3及TiO-2多元复合,并引入硼元素进行改性,得到的光催化材料在低浓度亚甲基蓝和四环素的降解中效果明显,其中,亚甲基蓝的降解率超过98％,四环素的降解率超过88％,本发明提供的硼改性的WO-3/TiO-2/CdS光催化材料的制备方法简单、步骤可控,应用前景广阔。(The invention relates to a boron modified photocatalytic material and a preparation method thereof 3 /TiO 2 the/CdS photocatalytic material is prepared by using nanometer CdS hollow spheres and echinoid WO 3 And TiO 2 The obtained photocatalytic material has obvious effect in the degradation of low-concentration methylene blue and tetracycline by multi-element compounding and introducing boron element for modification, wherein the degradation rate of the methylene blue exceeds 98 percent, the degradation rate of the tetracycline exceeds 88 percent, and the boron-modified WO provided by the invention 3 /TiO 2 The preparation method of the/CdS photocatalytic material is simple, controllable in steps and wide in application prospect.)

1. The preparation method of the boron modified photocatalytic material is characterized by comprising the following steps of:

(1) preparing nano CdS hollow spheres: adding cadmium chloride, thiourea and glutathione into a distilled aqueous solvent, uniformly stirring, carrying out hydrothermal reaction, and filtering, washing and drying after the reaction is finished to obtain a nano CdS hollow sphere;

(2) boron-modified WO₃/TiO₂Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride, tetrabutyl titanate and boric acid, stirring for 6-12h, starting hydrothermal reaction, filtering, washing and drying after the reaction is finished, and calcining a product obtained after drying to obtain the boron-modified WO₃/TiO₂A CdS photocatalytic material.

2. The method for preparing the boron modified photocatalytic material as claimed in claim 1, wherein the mass ratio of the cadmium chloride, the thiourea and the glutathione in the step (1) is 100:120-140: 100-110.

3. The method as claimed in claim 2, wherein the hydrothermal reaction temperature in step (1) is 230-280 ℃ and the reaction time is 3-12 h.

4. The method for preparing the boron modified photocatalytic material according to claim 1, wherein in the step (2), the nano CdS hollow spheres are as follows: tungsten hexachloride: tetrabutyl acid: the mass ratio of the boric acid is 100:25-40:25-70: 5-20.

5. The method as claimed in claim 1, wherein the hydrothermal reaction temperature in step (2) is 170-190 ℃ and the reaction time is 20-30 h.

6. The method as claimed in claim 1, wherein the temperature-raising rate in the calcination process in step (2) is 1-3 ℃/min, the calcination temperature is 460-550 ℃, and the calcination time is 30-60 min.

7. The method for preparing a boron-modified photocatalytic material according to claim 1, wherein the boron-modified WO obtained in step (2)₃/TiO₂WO in/CdS photocatalytic materials₃Is in the shape of sea urchin.

8. A boron modified WO prepared by the process of claims 1-7₃/TiO₂A CdS photocatalytic material.

Technical Field

The invention relates to the field of photocatalytic degradation materials, in particular to a boron modified photocatalytic material and a preparation method thereof.

Background

The photocatalytic degradation is a novel and efficient water pollution treatment method, and has good degradation effect on organic pollutants, such as organic dyes of methyl orange, methylene blue and the like, and antibiotics of tetracycline and the like. The photocatalytic degradation principle is that the photocatalyst absorbs light energy and generates electron transition to generate photoproduction electrons, holes and active free radicals with extremely strong activity, and then the organic pollutants are degraded into non-toxic or low-toxic inorganic matters through the reactions of substitution, addition, electron transfer and the like between the free radicals and the organic pollutants.

Common photocatalysts comprise titanium-based compounds such as titanium dioxide and the like, bismuth-based compounds such as bismuth bromate and the like, sulfides such as molybdenum disulfide and the like, wherein the cadmium sulfide is a typical II-VI semiconductor material, the forbidden band width is narrower and is between 2.4 and 2.5eV, has good photochemical activity under visible light and moderate oxidation-reduction potential, is a visible light response type semiconductor material with good photocatalytic performance, but the photo-generated electrons and holes of cadmium sulfide are easy to be combined, the photo-catalytic activity of cadmium sulfide is seriously influenced, tungsten oxide has high carrier mobility and good chemical stability, and the forbidden band width of the tungsten oxide is 2.6eV, and is matched with the energy band structure of cadmium sulfide, and the heterojunction structure can be constructed, the photoproduction charges can be effectively separated and transmitted, and the recombination and recombination of photoproduction electrons and holes can be inhibited by regulating and controlling the proportion of the tungsten oxide to the cadmium sulfide.

The preparation of multi-component composite photocatalysts by combining the characteristics of different materials is the hotspot of recent research, and the literature (Kim H, Kim J, Kim W, et al, enhanced photocatalytic and photochemical activity in the tertiary hybrid of CdS/TiO2/WO3 through the catalytic electron transfer [ J]The Journal of Physical Chemistry C,2011,115(19):9797-₂/WO₃The synthesis method of the ternary photocatalyst is that TiO is prepared by a sol-gel method₂/WO₃Binary hybrid, then hydrolyzing and precipitating to obtain CdS/TiO₂/WO₃A ternary dopant; literature data (Liu C, Li Y, Li W, et al. CdS quantum dots sensed plated plate WO3 photoelectrodes with a TiO2 buffer-layer [ J]Materials Letters,2014,120:170-₂/WO₃Three-way photocatalysts of which WO₃Preparation of plate-shaped film based on hydrothermal radio frequency sputtering and TiO₂The CdS is self-assembled by CBD technology after thermal hydrolysis plating. The invention provides a WO based on boron modification based on the existing research₃/TiO₂The CdS photocatalytic material and the preparation method thereof have the characteristics of simple synthesis and good material performance.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides WO based on boron modification₃/TiO₂The CdS photocatalytic material and the preparation method thereof solve the defects existing in the single-component photocatalytic material and have the characteristics of simple synthesis and good material performance.

In order to achieve the purpose, the invention provides the following technical scheme:

a preparation method of a boron modified photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding cadmium chloride, thiourea and glutathione into a distilled aqueous solvent, uniformly stirring, carrying out hydrothermal reaction, and filtering, washing and drying after the reaction is finished to obtain a nano CdS hollow sphere;

(2) boron-modified WO₃/TiO₂Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride, tetrabutyl titanate and boric acid, stirring for 6-12h, starting hydrothermal reaction, filtering, washing and drying after the reaction is finished, and calcining a product obtained after drying to obtain the boron-modified WO₃/TiO₂A CdS photocatalytic material.

Preferably, the mass ratio of the cadmium chloride, the thiourea and the glutathione in the step (1) is 100:120-140: 100-110.

Preferably, the hydrothermal reaction temperature in the step (1) is 230-280 ℃, and the reaction time is 3-12 h.

Preferably, in the step (2), the nano CdS hollow spheres are as follows: tungsten hexachloride: tetrabutyl titanate: the mass ratio of the boric acid is 100:25-40:25-70: 5-20.

Preferably, the hydrothermal reaction temperature in the step (2) is 170-.

Preferably, the temperature rise rate in the calcination process in the step (2) is 1-3 ℃/min, the calcination temperature is 460-550 ℃, and the calcination time is 30-60 min.

Preferably, the boron-modified WO obtained in step (2)₃/TiO₂WO in/CdS photocatalytic materials₃Is in the shape of sea urchin.

The invention also claims the boron modified WO prepared by the above method₃/TiO₂A CdS photocatalytic material.

Compared with the prior art, the invention has the following beneficial technical effects:

(1) the boron modified WO prepared by the invention₃/TiO₂The material is prepared from nanometer CdS hollow spheres and echinoid WO₃And TiO₂The obtained photocatalytic material has obvious effect in the degradation of low-concentration methylene blue and tetracycline by multi-element compounding and introducing boron element for modification, wherein the degradation rate of the methylene blue exceeds 98 percent, and the degradation rate of the tetracycline exceeds 88 percent.

(2) The nano CdS hollow sphere is obtained by taking glutathione as a macromolecular template agent, the unique hollow sphere structure has the characteristics of small particle size and high specific surface area, the contact area with organic pollutants is increased, the utilization rate of light energy is improved, and the hollow structure is favorable for shortening the transmission path of photo-generated electrons and hollow holes and accelerating the migration of the photo-generated electrons and the holes.

(3) Boron modified WO prepared by the invention₃/TiO₂In the case of a CdS photocatalytic material, WO₃The sea urchin-shaped photocatalyst is sea urchin-shaped and has abundant photochemical active sites; through modification of boron, the titanium dioxide can be effectively doped into a titanium dioxide crystal lattice, and the overall photocatalytic activity of the material is further improved.

(4) Based on the existing research, the invention can blend the prepared nano hollow CdS material with boron, tungsten and titanium sources by adopting simple hydrothermal reaction and calcination treatment to obtain boron modified CdSWO₃/TiO₂The preparation method of the/CdS photocatalytic material is simple and controllable in steps.

Detailed Description

The technical scheme of the invention is further illustrated by the following specific examples. The following examples are intended to illustrate the invention only and are not intended to limit the scope of the invention.

Example 1

WO modified by boron₃/TiO₂The preparation method of the/CdS photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding a distilled water solvent into a reaction bottle, then adding cadmium chloride, thiourea and glutathione, stirring uniformly, carrying out hydrothermal reaction for 3h at 230 ℃, filtering the solvent after the reaction is finished, washing a precipitate by using distilled water and ethanol, and drying to obtain a nano CdS hollow sphere;

wherein the mass ratio of the cadmium chloride to the thiourea to the glutathione is 100:120: 100;

(2) boron-modified WO₃/TiO₂Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride, tetrabutyl titanate and boric acid, stirring for 6 hours, performing hydrothermal reaction at 170 ℃ for 20 hours, filtering out the solvent after the reaction is finished, washing a precipitate product with distilled water and ethanol, drying, calcining the dried product to obtain the boron-modified WO₃/TiO₂A CdS photocatalytic material 1;

wherein the heating rate in the calcining process is 1 ℃/min, the calcining temperature is 460 ℃, and the calcining time is 30 min; nano CdS hollow spheres: tungsten hexachloride: tetrabutyl titanate: the mass ratio of the boric acid is 100:25:60: 10.

Example 2

WO modified by boron₃/TiO₂The preparation method of the/CdS photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding a distilled water solvent into a reaction bottle, then adding cadmium chloride, thiourea and glutathione, stirring uniformly, carrying out hydrothermal reaction for 6h at 245 ℃, filtering the solvent after the reaction is finished, washing a precipitate by using distilled water and ethanol, and drying to obtain a nano CdS hollow sphere;

wherein the mass ratio of the cadmium chloride to the thiourea to the glutathione is 100:125: 103;

(2) boron-modified WO₃/TiO₂Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride, tetrabutyl titanate and boric acid, stirring for 8 hours, performing hydrothermal reaction at 175 ℃ for 24 hours, filtering out the solvent after the reaction is finished, washing a precipitate product with distilled water and ethanol, drying, calcining the dried product to obtain the boron-modified WO₃/TiO₂A CdS photocatalytic material 2;

wherein the heating rate in the calcining process is 2 ℃/min, the calcining temperature is 480 ℃, and the calcining time is 40 min; nano CdS hollow spheres: tungsten hexachloride: tetrabutyl titanate: the mass ratio of the boric acid is 100:30:50: 5.

Example 3

WO modified by boron₃/TiO₂The preparation method of the/CdS photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding a distilled water solvent into a reaction bottle, then adding cadmium chloride, thiourea and glutathione, stirring uniformly, carrying out hydrothermal reaction for 8h at 250 ℃, filtering the solvent after the reaction is finished, washing a precipitate by using distilled water and ethanol, and drying to obtain a nano CdS hollow sphere;

wherein the mass ratio of the cadmium chloride to the thiourea to the glutathione is 100:132: 106;

(2) boron-modified WO₃/TiO₂Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride, tetrabutyl titanate and boric acid, stirring for 10 hours, performing hydrothermal reaction at 180 ℃ for 26 hours, filtering out the solvent after the reaction is finished, washing a precipitate product with distilled water and ethanol, drying, calcining the dried product to obtain the boron-modified WO₃/TiO₂A CdS photocatalytic material 3;

wherein the heating rate in the calcining process is 2 ℃/min, the calcining temperature is 500 ℃, and the calcining time is 50 min; nano CdS hollow spheres: tungsten hexachloride: tetrabutyl titanate: the mass ratio of the boric acid is 100:35:30: 10.

Example 4

WO modified by boron₃/TiO₂The preparation method of the/CdS photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding a distilled water solvent into a reaction bottle, then adding cadmium chloride, thiourea and glutathione, stirring uniformly, carrying out hydrothermal reaction for 8h at 265 ℃, filtering the solvent after the reaction is finished, washing a precipitate by using distilled water and ethanol, and drying to obtain a nano CdS hollow sphere;

wherein the mass ratio of the cadmium chloride to the thiourea to the glutathione is 100:140: 110;

(2) boron-modified WO₃/TiO₂Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride, tetrabutyl titanate and boric acid, stirring for 12 hours, performing hydrothermal reaction at 190 ℃ for 30 hours, filtering out the solvent after the reaction is finished, washing a precipitate product with distilled water and ethanol, drying, calcining the dried product to obtain the boron-modified WO₃/TiO₂A CdS photocatalytic material 4;

wherein the heating rate in the calcining process is 3 ℃/min, the calcining temperature is 520 ℃, and the calcining time is 60 min; nano CdS hollow spheres: tungsten hexachloride: tetrabutyl titanate: the mass ratio of the boric acid is 100:30:70: 15.

Comparative example 1

A preparation method of a photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding a distilled water solvent into a reaction bottle, then adding cadmium chloride, thiourea and glutathione, stirring uniformly, carrying out hydrothermal reaction for 3h at 230 ℃, filtering the solvent after the reaction is finished, washing a precipitate by using distilled water and ethanol, and drying to obtain a nano CdS hollow sphere;

wherein the mass ratio of the cadmium chloride to the thiourea to the glutathione is 100:120: 100;

(2) boron-modified WO₃Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride and boric acid, stirring for 6 hours, performing hydrothermal reaction at 170 ℃ for 20 hours, filtering out the solvent after the reaction is finished, washing a precipitate product with distilled water and ethanol, drying, and calcining the dried product to obtain a photocatalytic material 5;

wherein the heating rate in the calcining process is 1 ℃/min, the calcining temperature is 460 ℃, and the calcining time is 30 min; nano CdS hollow spheres: tungsten hexachloride: the mass ratio of the boric acid is 100:25: 10.

Comparative example 2

A preparation method of a photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding a distilled water solvent into a reaction bottle, then adding cadmium chloride, thiourea and glutathione, stirring uniformly, carrying out hydrothermal reaction for 3h at 230 ℃, filtering the solvent after the reaction is finished, washing a precipitate by using distilled water and ethanol, and drying to obtain a nano CdS hollow sphere;

wherein the mass ratio of the cadmium chloride to the thiourea to the glutathione is 100:120: 100;

(2)WO₃/TiO₂preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tungsten hexachloride and tetrabutyl titanate, stirring for 6 hours, performing hydrothermal reaction at 170 ℃ for 20 hours, filtering out the solvent after the reaction is finished, washing a precipitate product with distilled water and ethanol, drying, and calcining the dried product to obtain a photocatalytic material 6;

wherein the heating rate in the calcining process is 1 ℃/min, the calcining temperature is 460 ℃, and the calcining time is 30 min; nano CdS hollow spheres: tungsten hexachloride: the mass ratio of tetrabutyl titanate is 100:25: 60.

Comparative example 3

A preparation method of a photocatalytic material comprises the following steps:

(1) preparing nano CdS hollow spheres: adding a distilled water solvent into a reaction bottle, then adding cadmium chloride, thiourea and glutathione, stirring uniformly, carrying out hydrothermal reaction for 3h at 230 ℃, filtering the solvent after the reaction is finished, washing a precipitate by using distilled water and ethanol, and drying to obtain a nano CdS hollow sphere;

wherein the mass ratio of the cadmium chloride to the thiourea to the glutathione is 100:120: 100;

(2) boron modified TiO₂Preparation of CdS photocatalytic material: adding the nano CdS hollow spheres obtained in the step (1) into an ethanol solvent, performing ultrasonic dispersion treatment, adding tetrabutyl titanate and boric acid, stirring for 6 hours, performing hydrothermal reaction at 170 ℃ for 20 hours, filtering out the solvent after the reaction is finished, washing a precipitate product with distilled water and ethanol, drying, calcining the dried product to obtain the boron-modified WO₃/TiO₂A CdS photocatalytic material 7;

wherein the heating rate in the calcining process is 1 ℃/min, the calcining temperature is 460 ℃, and the calcining time is 30 min; nano CdS hollow spheres: tetrabutyl titanate: the mass ratio of the boric acid is 100:60: 10.

Test examples

The photocatalysts prepared in the examples and the comparative examples are subjected to photocatalytic evaluation, and the specific performance evaluation method is as follows:

degradation test of methylene blue: adding a methylene blue solution with the mass fraction of 0.1% into a reaction bottle, then adding the catalytic material prepared in each example and comparative example, wherein the added mass fraction is 0.3%, using a 500W xenon lamp as a light source, irradiating for 3h, and detecting the degradation concentration of the methylene blue by using a UV-3100 UV-visible spectrophotometer, wherein the test standard is GB/T23762-.

TABLE 1 methylene blue degradation test results

Degradation test of tetracycline: adding a tetracycline solution with the mass fraction of 0.05% into a reaction bottle, then adding the catalytic material prepared in each example and comparative example, wherein the added mass fraction is 0.2%, using a 500W xenon lamp as a light source, irradiating for 6h, and detecting the degradation concentration of the tetracycline by using a UV-3100 UV-visible spectrophotometer, wherein the test standard is GB/T23762-.

TABLE 2 Tetracycline degradation test results

It should be noted that the above-described embodiments may enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way. Thus, it will be appreciated by those skilled in the art that the invention may be modified and equivalents may be substituted; all technical solutions and modifications thereof which do not depart from the spirit and technical essence of the present invention should be covered by the scope of the present patent.