阅读说明：本技术 一种山茶花状ZnO/SnO-SnO2复合材料及其制备方法和应用 (Camellia flower-shaped ZnO/SnO-SnO2Composite material and preparation method and application thereof ) 是由 张永辉 王超楠 巩飞龙 陈俊利 孟二超 岳丽娟 方少明 张浩力 于 2020-06-28 设计创作，主要内容包括：本发明公开了一种山茶花状ZnO/SnO-SnO<Sub>2</Sub>复合材料及其制备方法和应用,所述山茶花状ZnO/SnO-SnO<Sub>2</Sub>复合材料由二维ZnO薄片自组装而成,SnO-SnO<Sub>2</Sub>混合物均匀地锚定在ZnO薄片上。首先以水热法合成SnO-SnO<Sub>2</Sub>混合纳米颗粒。随后,利用溶剂热法以AOT为软模板,将已制备的SnO-SnO<Sub>2</Sub>混合纳米颗粒加入到反应体系中,最后将复合材料在400℃下煅烧2h,得到山茶花状ZnO/SnO-SnO<Sub>2</Sub>复合材料。本发明在氧化锌的基础上复合SnO-SnO<Sub>2</Sub>纳米颗粒,提高了对胺类气体的灵敏度以及选择性,工作温度为100℃时,对三乙胺有较好的选择性并且对100ppm的三乙胺的灵敏度达到780。(The invention discloses camellia-shaped ZnO/SnO-SnO 2 Camellia-shaped ZnO/SnO-SnO as well as preparation method and application thereof 2 The composite material is formed by self-assembling two-dimensional ZnO slices, SnO-SnO 2 The mixture was uniformly anchored to the ZnO sheet. Firstly, synthesizing SnO-SnO by a hydrothermal method 2 The nanoparticles are mixed. Then, using a solvothermal method and AOT as a soft template, and adding the prepared SnO-SnO 2 Adding the mixed nano particles into a reaction system, and finally calcining the composite material at 400 ℃ for 2h to obtain camellia-shaped ZnO/SnO-SnO 2 A composite material. The invention compounds SnO-SnO on the basis of zinc oxide 2 The nanometer particles improve the sensitivity and the selectivity to amine gas, have better selectivity to triethylamine at the working temperature of 100 ℃, and the sensitivity to 100ppm of triethylamine reaches 780.)

1. Camellia flower-shaped ZnO/SnO-SnO₂A composite material characterized by: the camellia-shaped ZnO/SnO-SnO₂The composite material is formed by self-assembling two-dimensional ZnO slices, SnO-SnO₂The mixture was uniformly anchored to the ZnO sheet.

2. Camellia-like ZnO/SnO-SnO according to claim 1₂The preparation method of the composite material is characterized by comprising the following steps:

(1) preparing tin oxide: dissolving a precipitant I in a mixed solution of low-carbon alcohol and deionized water, adding a divalent tin compound after stirring and dissolving, adding a precipitant II into the mixed solution under a stirring state, and stirring to obtain a suspension; after high-temperature reaction, calcining in inert atmosphere to obtain SnO-SnO₂Mixing;

(2) preparing a zinc salt solution: dissolving a surfactant in a mixed solution of low-carbon alcohol and deionized water, and adding zinc salt into the surfactant solution to prepare a zinc salt solution;

(3) preparation of camellia-shaped ZnO/SnO-SnO₂The composite material comprises the following components: adding a precipitator II into the zinc salt solution obtained in the step (2), stirring, and adding SnO-SnO₂The mixture is obtained into suspension; after the high-temperature reaction, washing, drying and calcining the obtained product to obtain camellia-shaped ZnO/SnO-SnO₂A composite material.

3. Camellia-like ZnO/SnO-SnO according to claim 2₂Of composite materialsThe preparation method is characterized by comprising the following steps: the divalent tin compound is SnC₂O₄、SnSO₄、Na₂SnO₂Or SnCl₂.2H₂O; the precipitator I is hexamethylenetetramine, ammonia water or NaOH; the precipitator II is urea, ethanolamine or sodium citrate; the lower alcohol is methanol, ethanol or ethylene glycol; the volume ratio of the low-carbon alcohol to the deionized water is 1 (0.1-1.7).

4. Camellia-like ZnO/SnO-SnO according to claim 2₂The preparation method of the composite material is characterized by comprising the following steps: the concentration of the divalent tin compound in the suspension obtained in the step (1) is 0.0025-0.0375mol/L, the mass ratio of the divalent tin compound to the precipitating agent I is 1 (0.3-1), and the mass ratio of the divalent tin compound to the precipitating agent II is 1: (0.5-1.5).

5. Camellia-like ZnO/SnO-SnO according to claim 2₂The preparation method of the composite material is characterized by comprising the following steps: the temperature of the high-temperature reaction in the step (1) is 120 ℃, and the reaction time is 12 h; the calcining temperature is 400 ℃, and the calcining time is (1-3) h.

6. Camellia-like ZnO/SnO-SnO according to claim 2₂The preparation method of the composite material is characterized by comprising the following steps: in the step (2), the surfactant is an anionic surfactant or a cationic surfactant, the anionic surfactant is a sodium succinate anionic surfactant, and the cationic surfactant is an amine salt cationic surfactant, a quaternary ammonium salt cationic surfactant, an onium salt cationic surfactant, an amine oxide cationic surfactant or a heterocyclic cationic surfactant.

7. Camellia-like ZnO/SnO-SnO according to claim 2₂The preparation method of the composite material is characterized by comprising the following steps: the zinc salt in the step (2) is zinc acetate, zinc nitrate or zinc chloride; the ratio of the zinc salt to the amount of surfactant is 1 (0.3-1.2).

8. Camellia-like ZnO/SnO-SnO according to claim 2₂The preparation method of the composite material is characterized by comprising the following steps: the mass ratio of the zinc salt to the precipitant II in the step (3) is 1: (0.5-1.5); SnO-SnO₂The addition amount of the mixture is based on 1mmol of zinc salt, and SnO-SnO is required₂The mass of the mixture is 0.0045-0.225 g.

9. Camellia-like ZnO/SnO-SnO according to claim 2₂The preparation method of the composite material is characterized by comprising the following steps: the reaction temperature in the step (3) is 110-180 ℃, and the reaction time is 3-22 h; the calcining temperature is 400 ℃, and the calcining time is 1-3 h.

10. Camellia-like ZnO/SnO-SnO according to claim 1₂The composite material is used as a gas sensor in the aspect of amine sensors.

Technical Field

The invention relates to camellia-shaped ZnO/SnO-SnO₂Preparation of composite material and application in amine sensor.

Background

Amines are volatile organic compounds, some of which are toxic and harmful and also have malodour. Such substances are mainly produced in the industrial processes of the manufacture of dyes and dye intermediates, rubber accelerators and antioxidants, photographic developers and also in the synthesis of pharmaceuticals, the production of fragrances, the curing of plastics and the manufacture of resins, the construction of coatings, lacquers, etc. The existence of amine substances in the atmosphere has great harm to the environment and human health. During the death and decay of fish and shellfish, Triethylamine (TEA) gas is released, the concentration increasing with decreasing freshness of the fish. TEA gas is not only toxic, but also flammable and explosive, and seriously harms human health, such as skin burn, headache, nausea and the like. It is extremely damaging to the respiratory system and can lead to pulmonary edema and even death. The environmental TEA concentration is limited to 10ppm according to the Occupational Safety and Health Administration (OSHA). The literature reports that ZnO-SnO with hollow interior is synthesized by adopting a two-step method₂Heterojunction nanotubes (Sensors)&Activators: b. Chemical 279, 2019, 410-417), the prepared triethylamine sensor has a high operating temperature and the response value remains very low after irradiation with ultraviolet laser. CN108931559A discloses a boron-doped graphene modified Au @ ZnO core-shell heterogeneous triethylamine sensor, which realizes triethylamine detection at near room temperature (50 ℃) by utilizing the high specific surface area of graphene and the p-type semiconductor characteristic of boron-doped graphene. However, the method still has the defects of low sensitivity, complicated preparation and the like. M-toluidine, which has a contact limit of 2ppm, is a strong methemoglobin former and can irritate the urinary bladder and cause hematuria. Contact with the skin can cause symptoms such as burning of the face, severe headache, dizziness, dyspnea, etc. And the danger of combustion and explosion caused by naked fire, high heat or strong oxidant, and high heatAnd toxic gas is decomposed. Aniline is a carcinogenic substance and can cause chronic poisoning and damage to liver, kidney, skin, etc. Few reports on aniline sensors have been made, and CN103336034A discloses an aniline gas sensor and a preparation method thereof. The ZnS/PTCDA core-shell nano-particles are synthesized by a two-step method, and the prepared gas sensor can realize the selectivity of the p-aniline, but the selectivity of the p-aniline under low concentration is not outstanding. The existing amine sensor still has the defects of high working temperature, poor sensitivity and the like. Therefore, there is a need to develop a high sensitivity, low operating temperature, low cost and stable amine gas sensor.

Disclosure of Invention

The invention aims to solve the technical problem of providing ZnO/SnO-SnO with high sensitivity, low power consumption and excellent selectivity to amine gas aiming at the defects of low sensitivity, high working temperature and the like of amine sensors₂Composite materials and methods for making the same.

In order to solve the technical problems, the following technical scheme is adopted:

the camellia-shaped ZnO/SnO-SnO of the invention₂The composite material is formed by self-assembling two-dimensional ZnO slices, SnO-SnO₂The hybrid nanoparticles are anchored to the ZnO sheet.

The camellia-shaped ZnO/SnO-SnO of the invention₂The preparation method of the composite material comprises the following steps: firstly, synthesizing SnO-SnO by a hydrothermal method₂The nanoparticles are mixed. Then, using a solvothermal method and AOT as a soft template, and adding the prepared SnO-SnO₂Adding the mixed nano particles into a reaction system, and finally calcining the composite material at 400 ℃ for 2h to obtain camellia-shaped ZnO/SnO-SnO₂A composite material.

The camellia-flower-shaped ZnO/SnO-SnO₂The preparation method of the composite material comprises the following specific steps:

(1) preparing tin oxide: dissolving a precipitant I in a mixed solution of low-carbon alcohol and deionized water, adding a divalent tin compound after stirring and dissolving, adding a precipitant II into the mixed solution under a stirring state, and stirring to obtain a suspension; after high-temperature reaction, calcining in inert atmosphere to obtain SnO-SnO₂Mixing;

(2) preparing a zinc salt solution: dissolving a surfactant in a mixed solution of low-carbon alcohol and deionized water, and adding zinc salt into the surfactant solution to prepare a zinc salt solution;

(3) preparation of camellia-shaped ZnO/SnO-SnO₂The composite material comprises the following components: adding a precipitator II into the zinc salt solution obtained in the step (2), stirring, and adding SnO-SnO₂The mixture is obtained into suspension; after the high-temperature reaction, washing, drying and calcining the obtained product to obtain camellia-shaped ZnO/SnO-SnO₂A composite material.

Further, the divalent tin compound is SnC₂O₄、SnSO₄、Na₂SnO₂Or SnCl₂.2H₂O; the precipitator I is hexamethylenetetramine, ammonia water or NaOH; the precipitator II is urea, ethanolamine or sodium citrate; the lower alcohol is methanol, ethanol or ethylene glycol; the volume ratio of the low-carbon alcohol to the deionized water is 1 (0.1-1.7).

Further, the concentration of the divalent tin compound in the suspension obtained in the step (1) is 0.0025-0.0375mol/L, the mass ratio of the divalent tin compound to the precipitating agent I is 1 (0.3-1), and the mass ratio of the divalent tin compound to the precipitating agent II is 1: (0.5-1.5).

Further, the temperature of the high-temperature reaction in the step (1) is 120 ℃, and the reaction time is 12 hours; the calcining temperature is 400 ℃, and the calcining time is (1-3) h.

Further, in the step (2), the surfactant is an anionic surfactant or a cationic surfactant, the anionic surfactant is a sodium succinate anionic surfactant, and the cationic surfactant is an amine salt cationic surfactant, a quaternary ammonium salt cationic surfactant, an onium salt cationic surfactant, an amine oxide cationic surfactant or a heterocyclic cationic surfactant.

Further, the zinc salt in the step (2) is zinc acetate, zinc nitrate or zinc chloride; the ratio of the zinc salt to the amount of surfactant is 1 (0.3-1.2).

Further, zinc salt in the step (3)The mass ratio of the precipitant II to the precipitant II is 1: (0.5-1.5); SnO-SnO₂The addition amount of the mixture is based on 1mmol of zinc salt, and SnO-SnO is required₂The mass of the mixture is 0.0045-0.225 g.

Further, the reaction temperature in the step (3) is 110-; the calcining temperature is 400 ℃, and the calcining time is 1-3 h.

The camellia-shaped ZnO/SnO-SnO₂The composite material is used as a gas sensor in the aspect of amine sensors.

The key point of the innovation of the invention is to prepare three-dimensional camellia-shaped ZnO/SnO-SnO₂A composite material. The ZnO triethylamine sensor has a lot of materials, but the working temperature is high and the sensitivity is low. When the working temperature is 100 ℃, the invention has better selectivity to triethylamine and the sensitivity to 100ppm triethylamine reaches 780. At 160 ℃, excellent selectivity to m-toluidine was shown. When the temperature is continuously increased to 240 ℃, camellia-shaped ZnO/SnO-SnO₂The sensitivity of the composite material to aniline is highest.

The invention has the beneficial effects that: the invention compounds SnO-SnO on the basis of zinc oxide₂The nanometer particles improve the sensitivity and selectivity to amine gas; the sensitivity of the working temperature of 100 ℃ to 100ppm triethylamine gas is up to 780, which is lower than the working temperature of the existing triethylamine sensor; the sensitivity to 100ppm m-toluidine gas at the working temperature of 160 ℃ is as high as 42.5; the sensitivity to aniline is highest when the temperature is raised to 240 ℃. The method has high yield and low preparation cost; the shape and size of the material are uniform; has higher response to amine gas and is easy to realize industrialization.

Drawings

FIG. 1 shows camellia-like ZnO/SnO-SnO prepared in example 2₂XRD pattern of the composite.

FIG. 2 is a Field Emission Scanning Electron Microscope (FESEM) photograph of the camellia-like ZnO nanomaterial prepared in example 2.

FIG. 3 shows camellia-like ZnO/SnO-SnO prepared in example 2₂Field emission scanning electron microscope (FES) for composite materialsEM) photograph.

FIG. 4 shows camellia-like ZnO/SnO-SnO prepared in example 2₂XPS spectra of the composite.

FIG. 5 shows camellia-like ZnO/SnO-SnO prepared in example 2₂The composite material gas sensor is used for testing the selectivity of different harmful gases (100 ppm).

FIG. 6 shows different amounts of camellia-shaped ZnO/SnO-SnO prepared in example 2₂Response curve of composite gas sensor to 100ppm triethylamine gas.

FIG. 7 shows camellia-like ZnO/SnO-SnO prepared in example 2₂And (3) testing the cyclicity of the composite material gas sensor to 100ppm triethylamine.

Detailed Description

The present invention will be further described with reference to the following examples. It is to be understood that the following examples are illustrative only and are not intended to limit the scope of the invention, which is to be given numerous insubstantial modifications and adaptations by those skilled in the art based on the teachings set forth above.