阅读说明：本技术 一种CoWO4/Cu2O复合声催化剂及其制备方法和应用 (CoWO (cobalt oxide tungsten trioxide)4/Cu2O composite acoustic catalyst and preparation method and application thereof ) 是由 王思幻 徐亮 刘妮萍 吴学签 张琳 王新 于 2021-09-15 设计创作，主要内容包括：本发明公开一种CoWO-(4)/Cu-(2)O复合声催化剂及其制备方法和应用。将CoWO-(4)分散于去离子水中,搅拌10～20min后,加入CuSO-(4)·5H-(2)O,继续搅拌15～20min后,缓慢加入NaOH,继续搅拌10～20min,最后加入葡萄糖,搅拌30～40min,所得产物抽滤,用蒸馏水和无水乙醇洗涤,真空干燥,得CoWO-(4)/Cu-(2)O复合声催化剂。本发明制备的CoWO-(4)/Cu-(2)O复合声催化剂,Cu-(2)O和CoWO-(4)之间的界面电荷转移将提高电荷分离效率,从而加速水在固液界面的氧化和有机降解,是一种高效、稳定、低成本的声催化剂。(The invention discloses a CoWO 4 /Cu 2 O composite acoustic catalyst, preparation method and application thereof. Mixing CoWO 4 Dispersing in deionized water, stirring for 10-20 min, and adding CuSO 4 ·5H 2 And O, after continuously stirring for 15-20 min, slowly adding NaOH, continuously stirring for 10-20 min, finally adding glucose, stirring for 30-40 min, performing suction filtration on the obtained product, washing with distilled water and absolute ethyl alcohol, and performing vacuum drying to obtain CoWO 4 /Cu 2 O composite acoustic catalyst. CoWO prepared by the invention 4 /Cu 2 O-complex acoustic catalyst, Cu 2 O and CoWO 4 The interfacial charge transfer between the two can improve the charge separation efficiency, thereby accelerating the oxidation and organic degradation of water at a solid-liquid interface, and the acoustic catalyst is efficient, stable and low-cost.)

1. CoWO (cobalt oxide tungsten trioxide)₄/Cu₂The preparation method of the O composite acoustic catalyst is characterized by comprising the following steps: mixing CoWO₄Dispersing in deionized water, stirring for 10-20 min, and adding CuSO₄·5H₂O, after continuously stirring for 15-20 min, slowly adding NaOH, continuously stirring for 10-20 min, finally adding glucose, and stirring for 30-40 min, the obtained product is filtered, washed by distilled water and absolute ethyl alcohol and dried in vacuum to obtain CoWO₄/Cu₂O composite acoustic catalyst.

2. The method according to claim 1, wherein CoWO is added to the mixture at a ratio by mass₄:CuSO₄·5H₂O＝1:0.1～1。

3. The method according to claim 1, wherein the CuSO is added in a mass ratio₄·5H₂O:NaOH＝1:1。

4. The method according to claim 1, wherein the CuSO is added in a mass ratio₄·5H₂And O is glucose 5: 4.

5. CoWO prepared according to the process of claim 1₄/Cu₂The application of the O composite acoustic catalyst in catalyzing and degrading organic pollutants.

6. Use according to claim 5, characterized in that the method is as follows: adding CoWO to wastewater containing organic contaminants₄/Cu₂O composite acoustic catalyst, ultrasonic catalysis.

7. Use according to claim 6, wherein the concentration of organic contaminants is 10 mg/L.

8. Use according to claim 7, characterized in that CoWO₄/Cu₂The amount of the O-complex catalyst added was 1 g/L.

9. The use according to any one of claims 5 to 8, wherein the organic contaminant is ofloxacin.

Technical Field

The invention belongs to the technical field of acoustic catalytic oxidation, and particularly relates to CoWO₄/Cu₂O composite acoustic catalyst, preparation method and application thereof.

Background

Cobalt tungstate (CoWO)₄) Is a well-known p-type semiconductor with a bandgap of 2.80 eV. Since CoWO₄Has the characteristics of chemical and physical stability, environmental friendliness, low cost, strong oxidation strength and the like, and is widely applied in the acoustic catalysis process. However, CoWO₄Is limited by the rapid recombination of electron-hole pairs. To overcome these drawbacks, an effective strategy is to combine such semiconductors with narrow bandgap semiconductors having appropriate band energies. In recent years, it has been confirmed that p-n and n-n heterojunctions between semiconductors generate an internal electric field in the junction region, resulting in effective carrier separation. When metal ions with different valence states are doped into the nano semiconductor material, the catalytic activity of the material can be improved to a great extent, and therefore, an acoustic catalytic material with high catalytic activity and low cost is urgently needed.

Disclosure of Invention

The invention aims to provide a CoWO for delaying the recombination of carriers by surface modification₄/Cu₂O composite acoustic catalyst, preparation method and application thereof.

The technical scheme adopted by the invention is as follows: CoWO (cobalt oxide tungsten trioxide)₄/Cu₂The preparation method of the O composite acoustic catalyst comprises the following steps: mixing CoWO₄Dispersing in deionized water, stirring for 10-20 min, and adding CuSO₄·5H₂And O, after continuously stirring for 15-20 min, slowly adding NaOH, continuously stirring for 10-20 min, finally adding glucose, stirring for 30-40 min, performing suction filtration on the obtained product, washing with distilled water and absolute ethyl alcohol, and performing vacuum drying to obtain CoWO₄/Cu₂O composite acoustic catalyst.

Further, the above preparation method, by mass ratio, CoWO₄:CuSO₄·5H₂O＝1:0.1～1。

Further, the preparation method comprises the following step of preparing CuSO according to the mass ratio₄·5H₂O:NaOH＝1:1。

Further, the preparation method comprises the following step of preparing CuSO according to the mass ratio₄·5H₂And O is glucose 5: 4.

CoWO provided by the invention₄/Cu₂The application of the O composite acoustic catalyst in catalyzing and degrading organic pollutants.

Further, the method is as follows: adding CoWO to wastewater containing organic contaminants₄/Cu₂O composite acoustic catalyst, ultrasonic catalysis.

Further, the concentration of the organic pollutants was 10 mg/L.

Further, CoWO₄/Cu₂The amount of the O-complex catalyst added was 1 g/L.

Further, the organic contaminant is ofloxacin.

The invention has the beneficial effects that:

1. the invention has cheap and easily obtained reagents, is suitable for expanded production, and is a high-efficiency, stable and low-cost acoustic catalyst.

2. CoWO prepared by the invention₄/Cu₂The O composite acoustic catalyst directly forms a Z-shaped heterojunction system, can improve the separation efficiency of photoinduced electron hole pairs, and has good oxidation-reduction capability and good acoustic catalytic performance. Such Cu₂O and CoWO₄The interfacial charge transfer between the two can improve the charge separation efficiency, thereby accelerating the oxidation and organic degradation of water at the solid-liquid interface.

Drawings

FIG. 1 is a CoWO prepared in example 1₄And CoWO₄/Cu₂XRD diffractogram of O-complex acoustic catalyst.

FIG. 2 is a CoWO prepared in example 1₄And CoWO₄/Cu₂XPS spectra of O composite acoustic catalysts.

FIG. 3 shows CoWO prepared by different compounding ratios₄/Cu₂O complexThe effect of the chorus catalyst on the catalytic ultrasonic degradation of ofloxacin solution is shown in the figure.

Detailed Description

Example 1 CoWO₄/Cu₂O-complex acoustic catalyst

The preparation method comprises

1、CoWO₄Preparation of

1.4551g of Co (NO)₃)₂·6H₂O and 1.6493g Na₂WO₄·2H₂Adding O into a 100mL conical flask filled with 30mL deionized water, magnetically stirring for 30min, performing ultrasonic reaction for 30min, pouring the obtained mixture into a polytetrafluoroethylene reaction kettle, and placing the polytetrafluoroethylene reaction kettle into a forced air drying oven for hydrothermal reaction at 180 ℃ for 24 h; filtering after the reaction is finished, drying for 2h at 80 ℃, grinding into fine powder by using an agate mortar to obtain CoWO₄And (3) powder.

2、CoWO₄/Cu₂Preparation of O-complex acoustic catalyst

200mg(0.65mmol)CoWO₄Adding into a conical flask containing 100mL deionized water, stirring for 10min, adding 200mg (0.8mmol) of CuSO₄·5H₂O, stirring for 15min to ensure Cu⁺Uniformly distributed in CoWO₄A surface. 200mg NaOH was then added slowly and stirring was continued for 10 min. Finally adding 160mg of glucose, stirring for 30min, carrying out suction filtration on the obtained product, washing the product for a plurality of times by using distilled water and absolute ethyl alcohol, and drying the product in vacuum for 2h to obtain CoWO (copper to Co) with the molar ratio of 1 to 0.8₄/Cu₂O composite acoustic catalyst.

(II) characterization

FIG. 1 shows CoWO₄And CoWO₄/Cu₂XRD diffractogram of O-complex acoustic catalyst. CoWO (cobalt oxide)₄/Cu₂Diffraction peak of O composite material and CoWO₄Similarly, illustrate Cu₂Introduction of O unchanged CoWO₄The crystal structure of (1).

FIG. 2 shows CoWO₄And CoWO₄/Cu₂XPS spectra of O composite acoustic catalysts. CoWO (cobalt oxide)₄Shows CoWO₄The sample contains Co, W and O elements, in CoWO₄/Cu₂Co, W, O, Cu were observed in the spectrum of O. This is achieved byThese results indicate that CoWO has been successfully prepared₄/Cu₂And (3) an O composite material.

Example 2 CoWO₄/Cu₂O-complex acoustic catalyst

The preparation method comprises the following steps:

200mg(0.65mmol)CoWO₄adding into a conical flask containing 100mL deionized water, stirring for 10min, adding 100mg (0.4mmol) of CuSO₄·5H₂O, stirring for 15min to ensure Cu⁺Uniformly distributed in CoWO₄A surface. 100mg NaOH was then added slowly and stirring was continued for 10 min. Finally adding 80mg of glucose, stirring for 30min, carrying out suction filtration on the obtained product, washing the product for a plurality of times by using distilled water and absolute ethyl alcohol, and drying the product in vacuum for 2h to obtain CoWO (copper to Co) with the molar ratio of 1 to 1.6₄/Cu₂O composite acoustic catalyst.

Example 3 CoWO₄/Cu₂O-complex acoustic catalyst

The preparation method comprises the following steps:

200mg(0.65mmol)CoWO₄adding into a conical flask containing 100mL deionized water, stirring for 10min, adding 40mg (0.16mmol) of CuSO₄·5H₂O, stirring for 15min to ensure Cu⁺Uniformly distributed in CoWO₄A surface. 40mg NaOH was then added slowly and stirring was continued for 10 min. Finally adding 32mg of glucose, stirring for 30min, carrying out suction filtration on the obtained product, washing the product for a plurality of times by using distilled water and absolute ethyl alcohol, and drying the product in vacuum for 2h to obtain CoWO (copper to Co) with the molar ratio of 1 to 4₄/Cu₂O composite acoustic catalyst.

Example 4 CoWO₄/Cu₂O-complex acoustic catalyst

The preparation method comprises the following steps:

200mg(0.65mmol)CoWO₄adding into a conical flask containing 100mL deionized water, stirring for 10min, adding 20mg (0.08mmol) of CuSO₄·5H₂O, stirring for 15min to ensure Cu⁺Uniformly distributed in CoWO₄A surface. Then 20mg NaOH was added slowly and stirring was continued for 10 min. Finally, 16mg of glucose was added and stirred for 30 min. Filtering the obtained product, washing with distilled water and anhydrous ethanol for several times, and vacuum drying2h, obtaining CoWO with the molar ratio of Cu to Co being 1:8₄/Cu₂O composite acoustic catalyst.

Example 5 CoWO₄/Cu₂O composite acoustic catalyst for degrading ofloxacin

CoWO was evaluated by degrading ofloxacin solution using ultrasound, measuring the maximum absorption wavelength thereof, and calculating the absorbance₄/Cu₂Acoustic catalytic activity of O-composite.

The method comprises the following steps: separately weighing CoWO₄And CoWO prepared in examples 1 to 4₄/Cu₂20mg of O composite acoustic catalyst is added into 20mL of ofloxacin solution with the concentration of 10mg/L, and the mixture is subjected to ultrasonic catalysis for 2h, the ultrasonic power is 200W, and the ultrasonic temperature is 20 ℃. Taking 10mL of the treated suspension sample, taking a supernatant after sampling and centrifuging, centrifuging at 18000rpm for 20min, removing suspended particles, measuring the UV-vis spectrum of the supernatant in 200-400nm, and determining the degradation rate of the ofloxacin solution at the lambda of the solution_maxCalculated as the absorbance at 291nm,

the formula is that the percent (%) degradation is [ (A)₀-A_t)/A₀]×100％

A₀Is the initial absorbance of ofloxacin

A_tIs the absorbance of ofloxacin at time t

As can be seen in FIG. 3, the appropriate concentration of Cu₂CoWO made by Oco₄The surface is uniformly dispersed, which is beneficial to the transfer and separation of electrons and holes. In Cu₂The prepared compound successfully degrades ofloxacin in the presence of O, and CoWO prepared when the molar ratio of Cu to Co is 1:8₄/Cu₂The degradation rate of the O composite acoustic catalyst to ofloxacin is the maximum and reaches 54.1 percent.