CN110280274B

CN110280274B - A wide-spectrum response photocatalytic material based on TiO2 array optical waveguide and its preparation method and application

Info

Publication number: CN110280274B
Application number: CN201910705588.3A
Authority: CN
Inventors: 桑元华; 高文强; 王晓宁; 王书华; ***; 刘宏
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2019-08-01
Filing date: 2019-08-01
Publication date: 2021-09-07
Anticipated expiration: 2039-08-01
Also published as: CN110280274A

Abstract

本发明涉及一种基于TiO₂阵列光波导的宽光谱响应光催化材料及其制备方法与应用，该光催化材料包括光纤，所述的光纤表面原位生长有TiO₂阵列；所述的TiO₂阵列上原位生长有可见光光催化剂或/和近红外光催化剂。本发明通过在光纤表面原位生长TiO₂阵列，来实现催化材料的固载，避免了二氧化钛催化剂的聚集，容易脱落的问题。通过在光导纤维表面原位生长TiO₂阵列及在阵列上构建以可见光响应的CdS与近红外光响应的WS₂为代表的的二级结构，实现了连续光催化高效在全光谱太阳光下降解以甲基橙为代表的有机染料，经过连续光催化降解***，能够有效的降解有机染料。The invention relates to a wide spectrum response photocatalytic material based on a _TiO2 array optical waveguide and a preparation method and application thereof. The photocatalytic material comprises an optical fiber, and the surface of the optical fiber is in-situ grown with a _TiO2 array; the _TiO2 Visible light photocatalysts or/and near-infrared photocatalysts are grown in situ on the array. The invention realizes the immobilization of the catalytic material by in-situ growth of the _TiO2 array on the surface of the optical fiber, and avoids the problems of aggregation and easy falling off of the titanium dioxide catalyst. By in situ growing _TiO2 arrays on the surface of optical fibers and constructing secondary structures represented by visible light-responsive CdS and near-infrared light-responsive WS2 _on the arrays, continuous photocatalytic high-efficiency degradation under full-spectrum sunlight was achieved. Organic dyes represented by methyl orange can effectively degrade organic dyes through a continuous photocatalytic degradation system.

Description

Based on TiO2Wide-spectral-response photocatalytic material of array optical waveguide and preparation method and application thereof

Technical Field

The invention relates to a method for preparing a catalyst based on TiO₂A wide-spectrum response photocatalytic material of an array optical waveguide and a preparation method thereof belong to the technical field of photocatalytic materials.

Background

In recent years, social and economic development is seriously affected by pollution of water and the atmosphere. In order to solve the problem of environmental pollution, various means such as fenton's method, combustion method, microbial treatment, membrane treatment, etc. have been developed and utilized. With the development of semiconductor photocatalysis research, a photocatalysis technology is used as a technical means for photodegrading organic pollutants to solve the problem of environmental pollution, and the attention degree of researchers is greatly improved. Various means such as structure regulation and control, morphology regulation and control and the like are applied to the research of preparing the high-efficiency photocatalytic material. MakingTiO, the earliest discovered photocatalytic material₂Is considered to have the most practical industrial application value and is researched and applied most widely. Current stage TiO₂As the most stable photocatalytic material, the mass preparation technology can be realized, the performance regulation and control of the photocatalytic material also have remarkable progress, and the photocatalytic material is the photocatalytic material which is most likely to realize practical application at present. However, there is a practical conflict that limits its industrial application, i.e. TiO₂The increase in photocatalytic efficiency requires more active surface, limits the size of the catalyst material, and the small size of TiO₂The solid-liquid separation and recycling after the catalytic reaction are very difficult, and therefore, the development of the catalyst based on TiO is under way₂In the process of the photocatalytic material, various solid-liquid separation processes are avoided by adopting an immobilization mode. Such as loading the photocatalytic material on a glass fiber felt, loading on a filter membrane, directly loading on the wall of a container, loading the photocatalytic material in a zeolite structure, and the like. This structure does solve the problem of separation of the photocatalytic material from the treatment liquid, but not only the substrates, which are themselves opaque, absorb light, but also the sewage itself absorbs a large amount of light, resulting in a low utilization rate of the light source by photocatalysis, and at the same time, because of the TiO₂The forbidden band width limits the absorption of visible light and near infrared light under sunlight, and reduces the utilization rate of the sunlight. By effectively in TiO₂The secondary structure is loaded with visible light or near infrared light catalyst to form a composite structure for expanding spectrum absorption, which is to improve TiO₂Effective means of light absorption range, but how to better utilize different wavelengths of sunlight in their composite structures remains a challenge.

Optical fibers are well known as important pathways for optical propagation, and thus composites by constructing photocatalytic materials on optical fibers have been proposed and studied. Based on the optical propagation path of the optical fiber, the loss of ineffective light absorption can be overcome. This structural design was first proposed by Marinangeli and Ollis and theoretical studies were carried out, and then experiments for adhering TiO2 to an optical fiber using silica gel or the like were also successful and fundamental application studies on water treatment were carried out. Furthermore, the deposition of the catalyst on the optical fiber is also obtained by means of calcination after hydrolysis of the alkoxide of titanium, or by means of calcination after sol-gel coating.

However, the above methods are all loaded on the optical fiber by a chemical adhesion or sintering adhesion manner, the catalyst is easily in an agglomerated state, and the exposure of the catalytic active sites is limited, and in addition, the agglomeration of the nanoparticles can cause that photogenerated carriers generated inside are not easily transported to the surface of the catalyst, and the improvement of the catalytic efficiency is limited. In the loading mode, a large amount of residual stress exists in the obtained catalyst membrane, so that the catalyst membrane is easy to fall off in use, and the composite catalytic material is ineffective.

On the other hand, the single photocatalytic material is only used for a certain wavelength band in the spectrum, and the utilization efficiency of light is seriously affected, so that the design and research of the photocatalytic material capable of being used in multiple wavelength bands in the spectrum are realized, the utilization rate of light is improved, and the technical problem to be solved by the technical personnel in the field is urgently needed. The invention is therefore proposed.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a TiO-based material₂A wide-spectrum response photocatalytic material of an array optical waveguide and a preparation method thereof. The invention grows TiO on the surface of the optical fiber₂Array to realize the immobilization of catalytic material and the light is led out from the optical fiber and enters into TiO₂Arrayed and deposited by TiO₂Visible light, WS, with secondary structure CdS and the like constructed on the array₂The near infrared photocatalyst allows light to pass from the optical fiber to the TiO₂Single crystal arrays to CdS visible light catalyst or WS₂The near-infrared catalyst is a light propagation path, so that the promotion of the photocatalytic active sites of the material and the utilization rate of the broadened spectrum are realized, and the high-efficiency internally-communicated photocatalytic composite material is obtained.

The technical scheme of the invention is as follows:

based on TiO₂The wide-spectrum response photocatalytic material for the array optical waveguide comprises an optical fiber, wherein TiO is grown on the surface of the optical fiber in situ₂An array; the TiO is₂Visible light photocatalyst grown in situ on the array orAnd/or near infrared photocatalyst.

According to the invention, preferably, the visible light photocatalyst is CdS, and the near infrared photocatalyst is WS₂。

According to the present invention, preferably, the optical fiber is a silica optical fiber.

According to the invention, preferably, the TiO is₂The array is composed of nano rods with the length of 0.5-2 microns and nano dendrites with the length of 5-20 nanometers on the nano rods, and the nano dendrites uniformly grow on the quartz optical fiber and pass through TiO₂Nanorod and CdS/WS formed thereon₂TiO constructed by nano-dendrite₂An array of secondary structures.

According to the invention, preferably, the TiO is₂The array is subjected to hydrothermal loading at excess synthesis concentration to ensure TiO₂The array can be fully and uniformly loaded on the surface of the optical quartz fiber, so that the degradation catalytic reaction is carried out by utilizing ultraviolet light in a full spectrum in a maximum absorption manner. Preferably, TiO on the surface of the optical fiber₂The thickness of the uniform coverage is 5-10 microns.

According to the invention, preferably, TiO₂、CdS、WS₂The mass ratio of the three components is 1: (0.1-0.5): (0.1-0.5), and the visible light and near infrared light in a full spectrum are utilized to carry out degradation catalytic reaction with maximum absorption.

According to the invention, the above-mentioned TiO-based material₂The preparation method of the wide spectral response photocatalytic material of the array optical waveguide comprises the following steps:

providing a titanium salt solution, placing the optical fiber in the titanium salt solution, and carrying out hydrothermal reaction at 160-₂An array functional optical fiber;

providing a solution of cadmium salt, adding TiO₂Soaking the array functional fiber in cadmium salt solution, adding ammonia water and thiourea, and reacting in 70-90 deg.C water bath to obtain CdS/TiO₂An array functional optical fiber;

or/and providing a tungsten salt solution and adding TiO₂Array functional fiber or CdS/TiO₂Placing the array functional fiber in a tungsten salt solution, impregnating, and calcining at 400-600 ℃ in an inert atmosphere to obtain WS₂/TiO₂Array functional fiber, or WS₂/CdS/TiO₂And (4) array functional optical fibers.

According to the invention, preferably, the titanium salt is K₂TiO(C₂O₄)₂(ii) a Preferably, the solvent of the titanium salt solution is a mixed solvent of water and diethylene glycol (DEG), and more preferably, the volume ratio of water to diethylene glycol is 1: 3;

preferably, the concentration of the titanium salt solution is 0.04-0.06 mol/L.

According to the invention, preferably, the cadmium salt solution is a mixed aqueous solution of trisodium citrate and cadmium chloride; preferably, the concentration of the cadmium salt aqueous solution is 0.05 mol/L; preferably, the mole ratio of the trisodium citrate to the cadmium chloride to the ammonia water to the thiourea is (2-2.5): 1:0.2:4.

According to the present invention, preferably, the tungsten salt solution is (NH)₄)₂WS₄The concentration of the aqueous solution is 4-6 mmol/L. Preferably, the inert gas is argon; the calcination time is 4-6 hours.

According to the invention, the optical fiber is preferably placed vertically in a titanium salt solution. Titanium dioxide grows in situ on the surface of the optical fiber.

According to the invention, the optical fiber is preferably pretreated before growing as follows:

an optical fiber with a needle-shaped incident end is prepared by an array manufacturing and etching method, and then is soaked in a mixed solution of sulfuric acid and hydrogen peroxide. The process is to carry out the activation treatment of the surface of the optical fiber, so as to conveniently realize TiO₂Growth on the surface, not simple deposition. Preferably, the mass concentration of the sulfuric acid is 70% and the mass concentration of the hydrogen peroxide is 30%. Preferably, the soaking temperature is 80-100 ℃; preferably, the method for preparing the optical fiber having the needle-shaped incident end comprises the following steps: gathering the optical fibers into bundles, pouring the optical fibers with gelatin, cutting the gathered ends into planes, then putting the planes into 5wt% HF aqueous solution, taking the planes out for 1 to 2 hours, and heating and dissolving the planes to remove the gelatin to obtain the optical fibers with the pinpoint structure.

According to the invention, said TiO-based material₂Preparation method of wide spectral response photocatalytic material of array optical waveguide, and application thereofA preferred embodiment, comprises the steps of:

(1) soaking a commercial optical fiber (G652D) in acetone for more than 12 hours, removing a cladding, and sequentially ultrasonically cleaning the bare quartz optical fiber in acetone, ethanol and pure water;

(2) gathering the optical fibers into bundles, pouring the optical fibers with gelatin, cutting the gathered ends into planes, then putting the planes into 5wt% of HF aqueous solution, taking the optical fibers out and cleaning the optical fibers after 1 to 2 hours, and heating and dissolving the optical fibers to remove the gelatin to obtain the optical fibers with the pinpoint structure;

(3) the optical fiber was immersed in 70 wt% sulfuric acid and 30 wt% H₂O₂Soaking the mixed solution at 90 deg.C for 1 hr, and cleaning with clear water; the process is to carry out the activation treatment of the surface of the optical fiber, thereby being convenient for realizing TiO₂Growth on the surface, rather than simple deposition;

(4) adding 8mmol K₂TiO(C₂O₄)₂Adding 160mL of deionized water and diethylene glycol (DEG) mixed solvent in a volume of 1: 3; transferring the solution into a 200 ml stainless steel autoclave with a polytetrafluoroethylene lining; one end of the quartz fiber is bundled by a polytetrafluoroethylene adhesive tape and is vertically placed in a polytetrafluoroethylene lining, and the bundling side faces downwards; subjecting the sample to hydrothermal treatment at 180 deg.C for 3-9 h, thoroughly washing with deionized water, and drying at 80 deg.C overnight to obtain TiO₂An array functional optical fiber;

(5) adding trisodium citrate (0.03g/ml) and cadmium chloride (0.01g/ml) into 30ml of deionized water, and growing TiO in situ₂The arrayed optical fibers were immersed for 1 hour, then 1.5 ml of 28 wt% ammonia water and 14 ml of thiourea (0.015g/ml) were added, gently stirred in a water bath at 80 ℃ for 3 hours, thoroughly washed with deionized water, and vacuum-dried at 60 ℃ overnight to obtain CdS/TiO₂An array functional optical fiber;

(6) CdS/TiO₂The array functional fiber was soaked in 30mL of 5mM (NH)₄)₂WS₄After 20h in the solution, drying at 60 ℃ for 2h, calcining the functional optical fiber at 500 ℃ for 5 h in an argon-filled atmosphere to obtain WS₂/CdS/TiO₂And (4) array functional optical fibers.

According to the invention, said TiO-based material₂The wide-spectrum response photocatalytic material of the array optical waveguide is applied to photocatalytic sewage treatment. Preferably, the application method comprises the following steps:

let WS be₂/CdS/TiO₂One end of the array functional optical fiber tip is gathered into a bundle and is coupled with the LED lamp through silica gel to carry out photocatalytic sewage treatment. Preferably, a plurality of coupling structures can be connected in series, and continuous photocatalytic treatment is realized by utilizing a multi-stage similar structure. The assembled processing device is shown in fig. 5.

The invention has the beneficial effects that:

1. the invention grows TiO on the surface of the optical fiber in situ₂The array realizes the immobilization of the catalytic material, and avoids the problems of aggregation and easy shedding of the titanium dioxide catalyst.

2. According to the invention, by TiO₂Constructing visible light catalyst, WS, with secondary structure, such as CdS₂The near infrared photocatalyst allows light to pass from the optical fiber to the TiO₂Single crystal arrays to CdS visible light catalyst or WS₂The near-infrared catalyst is a light propagation path, so that the promotion of the photocatalytic active sites of the material and the utilization rate of the broadened spectrum are realized, and the high-efficiency internally-communicated photocatalytic composite material is obtained.

3. The invention grows TiO on the surface of the optical fiber in situ₂Array and visible light response CdS and near infrared light response WS constructed on array₂The organic dye represented by methyl orange is efficiently degraded under full-spectrum sunlight by continuous photocatalysis, and the organic dye can be effectively degraded by a continuous photocatalytic degradation system.

Drawings

FIG. 1 shows TiO obtained in example 1₂TiO in array functional optical fiber₂Scanning Electron Micrographs (SEM) at different magnifications.

FIG. 2 shows TiO obtained in example 1₂The array function fiber optic propagates the image.

FIG. 3 shows TiO obtained in example 1₂And (3) an array functional optical fiber light propagation simulation diagram.

FIG. 4 shows WS obtained in example 1₂/CdS/TiO₂Schematic diagram of array functional fiber.

FIG. 5 is a photograph of the integrated continuous photocatalytic device in test example 1.

FIG. 6 is a graph showing the results of pollutant degradation performance data of the integrated continuous photocatalytic device in test example 1.

Detailed Description

The invention is further described, but not limited to, by the following examples in conjunction with the accompanying drawings.

Example 1

Based on TiO₂The preparation method of the wide spectral response photocatalytic material of the array optical waveguide comprises the following steps:

(4) adding 8mmol of K₂TiO(C₂O₄)₂Adding 160mL of deionized water and diethylene glycol (DEG) mixed solvent in a volume of 1: 3; transferring the solution into a 200 ml stainless steel autoclave with a polytetrafluoroethylene lining; one end of the quartz fiber is bundled by a polytetrafluoroethylene adhesive tape and is vertically placed in a polytetrafluoroethylene lining, and the bundling side faces downwards; subjecting the sample to hydrothermal treatment at 180 deg.C for 3-9 h, thoroughly washing with deionized water, and drying at 80 deg.C overnight to obtain TiO₂An array functional optical fiber;

(5) trisodium citrate (0.03g/ml) and cadmium chloride (0.01g/ml) were added to 30ml of deionized waterIn-situ growth of TiO₂The arrayed optical fibers were immersed for 1 hour, then 1.5 ml of 28 wt% ammonia water and 14 ml of thiourea (0.015g/ml) were added, gently stirred in a water bath at 80 ℃ for 3 hours, thoroughly washed with deionized water, and vacuum-dried at 60 ℃ overnight to obtain CdS/TiO₂An array functional optical fiber;

TiO obtained in this example₂TiO in array functional optical fiber₂Scanning Electron Microscope (SEM) and WS₂/CdS/TiO₂A Transmission Electron Microscope (TEM) is shown in FIG. 1. From FIG. 1, it can be seen that TiO₂The nano array realizes full coverage on quartz optical fiber, TiO₂The thickness of the uniform coating is about 7 μm, wherein the TiO₂The array consists of nanorods with the length of 1 micron and micro nano-crystals growing on the nanorods with the length of about 10 nanometers, and the micro-nano-crystals grow on the quartz optical fiber uniformly and pass through TiO₂Nanorod and CdS/WS formed thereon₂TiO constructed by nano-dendrite₂An array of secondary structures.

The TiO obtained in this example was added₂The array functional fiber was subjected to light propagation image testing as shown in fig. 2. From FIG. 2, it can be seen that TiO₂The light propagation path of the array-covered quartz optical fiber is single-sided light irradiation, the titanium dioxide coated fiber has a white appearance, and as the incident light increases, there is a release of light on the silica fiber acted on by the titanium dioxide, because, for bare silica fibers, most of the light is reflected into the silica at the silica-air interface due to the higher refractive index of silica (-1.54). Also for TiO₂Coated quartz optical fibre, TiO₂Has a higher refractive index, light will be in TiO₂-SiO₂Refraction to TiO at the interface₂In the middle, incident light and emergent light are simulated in the presence of TiO as shown in FIG. 3₂Of covered quartz fibres, fibre-TiO₂Interface directs light toward the TiO₂Propagating, causing a significant amount of light to escape from the fiber. This is consistent with the study of light transmission under red laser in bare silica fibers and titania functional silica fibers. The simulation diagram of light propagation is shown in fig. 3.

WS obtained in this example₂/CdS/TiO₂A schematic diagram of an arrayed functional fiber is shown in fig. 4. As can be seen from fig. 4, the present invention can realize the utilization and catalysis of ultraviolet, visible light, and near-infrared broad spectrum, and has a high light utilization rate.

Example 2

TiO with secondary structure₂The preparation method of the supported optical fiber photocatalytic material comprises the following steps:

(2) gathering the optical fibers into bundles, pouring the optical fibers with gelatin, cutting the gathered ends into planes, then putting the planes into 5wt% of HF aqueous solution, taking the planes out for 2 hours, cleaning the planes, and heating and dissolving the planes to remove the gelatin to obtain the optical fibers with the pinpoint structure;

(4) 6.5mmol of K₂TiO(C₂O₄)₂Adding 160mL of mixed solvent consisting of deionized water and diethylene glycol (DEG) according to the volume ratio of 1: 3; transferring the solution into a 200 ml stainless steel autoclave with a polytetrafluoroethylene lining; one end of the quartz fiber is bundled by a polytetrafluoroethylene adhesive tape and is vertically placed in a polytetrafluoroethylene lining, and the bundling side faces downwards; subjecting the sample to hydrothermal treatment at 160 deg.C for 9h, thoroughly washing with deionized water, and drying at 90 deg.C overnight to obtain TiO₂An array functional optical fiber;

(5) trisodium citrate (0.03g/ml) and cadmium chloride (0.01g/ml) were added to 30ml of deionised waterIn-situ growth of TiO in water₂The arrayed optical fibers were immersed for 1 hour, then 1.5 ml of 28 wt% ammonia water and 14 ml of thiourea (0.015g/ml) were added, gently stirred in a water bath at 80 ℃ for 3 hours, thoroughly washed with deionized water, and vacuum-dried at 60 ℃ overnight to obtain CdS/TiO₂And (4) array functional optical fibers.

Example 3

(4) adding 9mmol of K₂TiO(C₂O₄)₂Adding 160mL of mixed solvent consisting of deionized water and diethylene glycol (DEG) according to the volume ratio of 1: 3; transferring the solution into a 200 ml stainless steel autoclave with a polytetrafluoroethylene lining; one end of the quartz fiber is bundled by a polytetrafluoroethylene adhesive tape and is vertically placed in a polytetrafluoroethylene lining, and the bundling side faces downwards; subjecting the sample to hydrothermal treatment at 190 deg.C for 4 hr, thoroughly washing with deionized water, and drying at 70 deg.C overnight to obtain TiO₂An array functional optical fiber;

(5) adding TiO into the mixture₂The array functional fiber was soaked in 30mL of 5mM (NH)₄)₂WS₄After 20h in the solution, drying at 60 ℃ for 2h, calcining the functional optical fiber at 500 ℃ for 5 h in an argon-filled atmosphere to obtain WS₂/TiO₂And (4) array functional optical fibers.

Comparative example 1

On the basis of adsorption, P25 (a TiO)₂Nanoparticles) are coated on a light guide quartz fiber, the pretreated quartz fiber is soaked in NaOH solution for two hours, the surface of the quartz fiber is modified with more-OH, 50mgP25 is dispersed in water by ultrasonic waves, the quartz fiber with the surface modified with-OH is soaked in P25 dispersion liquid for 12 hours, the quartz fiber is slightly washed by deionized water and dried to obtain the quartz fiber covered by P25.

Comparative example 2

Tetrabutyltitanate (8.5mL) and diethanolamine (2.5mL) were dissolved in 35.5mL ethanol, followed by stirring at room temperature for 10min, followed by addition of 0.5mL water and subsequent stirring for 1 h. The optical fiber was dip coated at a rate of 1 mm/s. Finally, calcining the optical fiber after dip coating in the air at 600 ℃ for 6h to obtain TiO₂And (3) functional fibers.

Comparative example 3

As shown in example 1, except that:

omitting steps (5) and (6) to obtain TiO₂And (4) array functional optical fibers.

Test example 1

WS obtained in example 1₂/CdS/TiO₂One end of the array functional optical fiber tip is gathered into a bundle and is coupled with the LED lamp through silica gel to carry out integrated continuous photocatalytic sewage treatment. A photograph of the integrated continuous photocatalytic device is shown in FIG. 5.

The integrated continuous photocatalytic device consists of six photocatalytic reaction systems (namely TiO)₂The loaded fiber optic tips are gathered into a bundle at one end and coupled to an LED lamp via silica gel to form a reaction system). The methyl orange solution was flowed through the assembled reaction apparatus by a peristaltic pump at a rate of 5 mL/min. The color of the methyl orange is continuously decolored in the photocatalytic reaction device, and the methyl orange is basically colorless after flowing through the sixth coupling system. The photograph of FIG. 4 is an image taken after the reaction apparatus was operated for 1 hour, indicating that the reaction apparatus had some stability.

The test results are shown in fig. 6.

The results of the quantitative degradation test for the continuous photocatalytic degradation of methyl orange by each coupled system are shown in fig. 6. Each photocatalytic coupling system can degrade methyl orange by 20% in the process of flowing methyl orange.

Test example 2

The experiment of comparing whether example 1 and comparative examples 1 and 2 can be uniformly grown in the silica fiber by a scanning electron microscope proves that the TiO grown in example 1₂The structure can grow uniformly on the surface, while the comparative examples 1 and 2 have the condition of agglomeration and non-uniform growth. At the same time, loading TiO by different methods₂The quartz fiber is slightly ultrasonically treated to judge the firmness of the three samples, and experiments show that the example 1 is slightly ultrasonically treated in water and does not shed TiO₂The aqueous solution was clear with no white nanoparticles, whereas comparative examples 1,2 showed exfoliation of the nanoparticles, with some white turbidity in the aqueous solution, demonstrating that example 1 was more robust than comparative examples 1, 2.

Test example 3

TiO formed by growing example 1 and comparative examples 1,2, 3₂The integrated continuous photocatalysis device constructed by the quartz optical fiber with the secondary structure consists of six photocatalytic reaction systems (namely, the method is the same as that of the embodiment 1, and the methods of the comparative examples 1,2 and 3 adopt TiO₂The ends of the tips of the optical fibers loaded by the secondary structure constructed for the base are gathered into a bundle and are coupled with a full-spectrum LED lamp through silica gel to form a reaction system). The methyl orange solution was flowed through the assembled reaction apparatus by a peristaltic pump at a rate of 5 mL/min. The degradation performance of the continuous photocatalytic reaction device composed of the example 1 and the comparative examples 1,2 and 3 is compared by testing the degradation amount of methyl orange.

The results show that comparative examples 1,2 have a degradation rate of 50% for five hours, comparative example 3 has a degradation rate of 80% under the same conditions, and example 1 has a degradation rate of 100% under the same conditions, under the conditions of 20mg/L methyl orange degradation under full spectrum sunlight. Compared with comparative examples 1 and 2, the degradation efficiency is improved by 50% under the same conditions; example 1 was photocatalytic at full spectrum, further increasing the degradation rate compared to comparative example 3.

Claims

1.一种基于TiO₂阵列光波导的宽光谱响应光催化材料，其特征在于，该光催化材料包括光纤，所述的光纤表面原位生长有TiO₂阵列；所述的TiO₂阵列上原位生长有可见光光催化剂和近红外光催化剂；1. A wide-spectrum response photocatalytic material based on a TiO ₂ array optical waveguide, wherein the photocatalytic material comprises an optical fiber, and the surface of the optical fiber is in-situ grown with a TiO ₂ array _; There are visible light photocatalysts and near-infrared photocatalysts grown in situ;

所述的可见光光催化剂为CdS，所述的近红外光催化剂为WS₂；The visible light photocatalyst is CdS, and the near-infrared photocatalyst is WS ₂ ;

所述的TiO₂阵列为长度0.5-2微米的纳米棒与纳米棒上5-20纳米的纳米支晶组成，并均匀的生长在石英光导纤维上，通过TiO₂ 纳米棒与其上形成的CdS/WS₂纳米支晶构建的TiO₂二级结构阵列；The _TiO2 array is composed of nanorods with a length of _0.5-2 microns and nano-branch crystals of 5-20 nanometers on the nanorods, and is uniformly grown on the quartz optical fiber. _TiO2 secondary structure array constructed by WS2 nano-branched crystals _;

光导纤维表面的TiO₂均匀覆盖的厚度为5-10微米，TiO₂、CdS、WS₂三者的质量比为1：（0.1-0.5）：（0.1-0.5）。The thickness of the TiO ₂ on the surface of the optical fiber uniformly covered is 5-10 microns, and the mass ratio of TiO ₂ , CdS and WS ₂ is 1:(0.1-0.5):(0.1-0.5).

2.根据权利要求1所述的基于TiO₂阵列光波导的宽光谱响应光催化材料，其特征在于，所述的光纤为石英光纤。2 . The wide-spectrum response photocatalytic material based on TiO ₂ array optical waveguide according to claim 1 , wherein the optical fiber is a silica optical fiber. 3 .

3.权利要求1-2任一项所述的基于TiO₂阵列光波导的宽光谱响应光催化材料的制备方法，包括：3. The preparation method of the wide spectrum response photocatalytic material based on TiO ₂ array optical waveguide according to any one of claims 1-2, comprising:

提供钛盐溶液，将光纤置于钛盐溶液中，于160-200℃水热反应3h-9h，得TiO₂阵列功能光纤；Provide a titanium salt solution, place the optical fiber in the titanium salt solution, and perform a hydrothermal reaction at 160-200 ° C for 3h-9h to obtain a _TiO2 array functional fiber;

提供镉盐溶液，将TiO₂阵列功能光纤置于镉盐溶液中浸泡，然后加入氨水和硫脲，70-90℃水浴反应，得CdS/TiO₂阵列功能光纤；Provide a cadmium salt solution, soak the TiO ₂ array functional fiber in the cadmium salt solution, then add ammonia water and thiourea, and react in a water bath at 70-90 °C to obtain a CdS/TiO ₂ array functional fiber;

提供钨盐溶液，将CdS/ TiO₂阵列功能光纤置于钨盐溶液中，浸渍后再在惰性气氛下于400-600℃煅烧，得WS₂/CdS/TiO₂阵列功能光纤。A tungsten salt solution is provided, the CdS/TiO ₂ array functional fiber is placed in the tungsten salt solution, immersed and then calcined at 400-600 ℃ in an inert atmosphere to obtain a WS ₂ /CdS/TiO ₂ array functional fiber.

4.根据权利要求3所述的基于TiO₂阵列光波导的宽光谱响应光催化材料的制备方法，其特征在于，所述的钛盐为K₂TiO(C₂O₄)₂；钛盐溶液的溶剂为水与二甘醇(DEG)的混合溶剂，水与二甘醇的体积比为1：3；钛盐溶液的浓度为0.04-0.06mol/L 。4 . The method for preparing a wide-spectrum response photocatalytic material based on TiO ₂ array optical waveguide according to claim 3 , wherein the titanium salt is K ₂ TiO(C ₂ O ₄ ) ₂ ; titanium salt solution The solvent is a mixed solvent of water and diethylene glycol (DEG), and the volume ratio of water and diethylene glycol is 1:3; the concentration of the titanium salt solution is 0.04-0.06mol/L.

5.根据权利要求3所述的基于TiO₂阵列光波导的宽光谱响应光催化材料的制备方法，其特征在于，所述的镉盐溶液为柠檬酸三钠与氯化镉的混合水溶液，镉盐水溶液的浓度为0.05mol/L；柠檬酸三钠、氯化镉、氨水、硫脲的摩尔比为（2-2.5）：1:0.2:4；5. The method for preparing a wide-spectrum response photocatalytic material based on TiO ₂ array optical waveguide according to claim 3, wherein the cadmium salt solution is a mixed aqueous solution of trisodium citrate and cadmium chloride, and the cadmium salt solution is The concentration of the saline solution is 0.05mol/L; the molar ratio of trisodium citrate, cadmium chloride, ammonia water and thiourea is (2-2.5): 1:0.2:4;

所述的钨盐溶液为(NH₄)₂WS₄水溶液，浓度为4-6 mmol/L；The tungsten salt solution is (NH ₄ ) ₂ WS ₄ aqueous solution, and the concentration is 4-6 mmol/L;

光纤垂直置于钛盐溶液中，二氧化钛在光纤表面原位生长。The optical fiber is placed vertically in a titanium salt solution, and titanium dioxide grows in situ on the surface of the optical fiber.

6.根据权利要求3所述的基于TiO₂阵列光波导的宽光谱响应光催化材料的制备方法，其特征在于，光纤生长前进行如下预处理：6. The preparation method of a wide-spectrum response photocatalytic material based on TiO ₂ array optical waveguide according to claim 3, characterized in that, the following pretreatment is performed before the optical fiber is grown:

采用阵列制作和蚀刻的方法制备出具有针状入射端的光纤，然后在硫酸和双氧水混合溶液中浸泡处理；An optical fiber with a needle-shaped incident end is prepared by array fabrication and etching, and then soaked in a mixed solution of sulfuric acid and hydrogen peroxide;

制备具有针状入射端的光纤的方法为：将光纤聚集成束，用明胶浇灌，在聚集端切成平面，然后进入5wt%HF水溶液中，经过1-2小时，取出洗净后，加热溶解去除明胶，获得具有针尖结构的光纤。The method of preparing an optical fiber with a needle-shaped incident end is: gather the optical fiber into a bundle, pour it with gelatin, cut a plane at the gathering end, and then put it into a 5wt% HF aqueous solution, after 1-2 hours, take out and wash, and heat to dissolve and remove gelatin to obtain a fiber with a needle-tipped structure.

7.权利要求1-2任一项所述的基于TiO₂阵列光波导的宽光谱响应光催化材料在光催化污水处理中的应用。7. The application of the broad spectrum response photocatalytic material based on _TiO2 array optical waveguide according to any one of claims 1-2 in photocatalytic sewage treatment.