阅读说明：本技术 一种氧空位含量可调的CeO2纳米材料的制备方法 (Oxygen vacancy content adjustable CeO2Preparation method of nano material ) 是由 尹奎波 朱明芸 文一峰 宋淑贵 郑安琪 董麟 代云茜 孙立涛 于 2020-02-28 设计创作，主要内容包括：本发明属于纳米材料制造领域,特别涉及一种氧空位含量可调的CeO<Sub>2</Sub>纳米材料的制备方法。该方法将原料聚乙烯吡咯烷酮和六水硝酸铈溶于N,N-二甲基甲酰胺溶剂中混合均匀后得到原料混合物；将得到的原料混合物转移至聚四氟乙烯内衬中并用反应釜密封后进行溶剂热反应,反应后得到一种氧空位可控的CeO<Sub>2</Sub>纳米材料。本发明显著提高了调控CeO<Sub>2</Sub>氧空位含量的容量范围,同时本发明方法能有效提高了调控CeO<Sub>2</Sub>氧空位操作的安全性,简便性,及CeO<Sub>2</Sub>产物的分散性。(The invention belongs to the field of nano material manufacturing, and particularly relates to CeO with adjustable oxygen vacancy content 2 A method for preparing nano material. Dissolving raw materials of polyvinylpyrrolidone and cerous nitrate hexahydrate in an N, N-dimethylformamide solvent, and uniformly mixing to obtain a raw material mixture; transferring the obtained raw material mixture into a polytetrafluoroethylene lining, sealing the polytetrafluoroethylene lining by using a reaction kettle, and carrying out solvothermal reaction to obtain oxygen vacancy controllable CeO 2 And (3) nano materials. The invention obviously improves the regulation of CeO 2 The capacity range of the oxygen vacancy content is increased, and the method can effectively regulate and control CeO 2 Safety, simplicity of oxygen vacancy operation, and CeO 2 Dispersibility of the product.)

1. Oxygen vacancy content adjustable CeO₂The preparation method of the nano material is characterized by comprising the following steps: dissolving raw materials of polyvinylpyrrolidone and cerous nitrate hexahydrate in an N, N-dimethylformamide solvent, and uniformly mixing to obtain a raw material mixture; transferring the obtained raw material mixture into a polytetrafluoroethylene lining, sealing the polytetrafluoroethylene lining by using a reaction kettle, and carrying out solvothermal reaction to obtain oxygen vacancy controllable CeO₂And (3) nano materials.

2. The CeO with adjustable oxygen vacancy content of claim 1₂The preparation method of the nano material is characterized in that the molecular weight of the polyvinylpyrrolidone is 10,000-1300,000.

3. The CeO with adjustable oxygen vacancy content of claim 1₂The preparation method of the nano material is characterized in that the solvothermal reaction temperature is 100-200 ℃.

4. The CeO with adjustable oxygen vacancy content of claim 1₂The preparation method of the nano material is characterized in that the solvothermal reaction time is 1-30 hours.

5. The CeO with adjustable oxygen vacancy content of claim 1₂The preparation method of the nanometer material is characterized in that,the mass concentration of the cerium nitrate hexahydrate dispersed in the reaction solvent is 8.3-41.66 mg/m L.

6. The CeO with adjustable oxygen vacancy content of claim 1₂The preparation method of the nano material is characterized in that the volume ratio of the N, N-dimethylformamide solution to the lining of the reaction kettle is 8:25-20: 25.

7. The CeO with adjustable oxygen vacancy content of claim 1₂The preparation method of the nano material is characterized in that the mass concentration of the polyvinylpyrrolidone dispersed in the reaction solvent is 0-35 mg/m L.

Technical Field

The invention belongs to the field of nano material manufacturing, and particularly relates to CeO with adjustable oxygen vacancy content₂A method for preparing nano material.

Background

CeO₂The (cerium dioxide) nano material can be used as an electronic auxiliary agent, a metal catalyst carrier or an independent catalyst due to good oxidation-reduction performance and thermal stability, is widely concerned and researched in the field of energy catalysis, and has wide potential application prospect. In CeO₂The crystal structure of (1) is that Ce is 4a and O is 8c, and the unit cell parameter is about 5.4 Å, wherein O is easy to move or delete in the crystal, and the valence change of Ce is accompanied, therefore, CeO₂Can act as an O buffer, and the more O is absent, i.e., the more oxygen vacancies, the more CeO₂The higher the content of trivalent Ce in the crystal, the larger the O buffer capacity. In addition, rich oxygen vacancies may be imparted to CeO₂Nano materials have more excellent redox properties while maintaining the structural characteristics of the materials themselves, and thus have been widely studied.

Currently regulated CeO₂The method for controlling the content of oxygen vacancy mainly comprises the steps of controlling the doping of heterogeneous atoms; synthesis of CeO exposing specific Crystal faces₂Such as (200) plane; and CeO₂And (4) adjusting the size. J. Phys. chem. B, 2005, 109, 24380-₂The O buffer capacity of (2) is prepared by first mixing the raw material Ce (NO)₃)₃Dissolving in NaOH alkaline aqueous solution with different concentrations, and reacting at a specified temperature for a period of time to obtain CeO with different morphology structures₂And (3) nano materials. These topographically distinct products exhibit different exposed crystal planes and thus different O buffer capacities. And relates to a method for regulating CeO₂The report of the method for maintaining the structure morphology and the structure of the nano material unchanged while the oxygen vacancy content of the nano material is not found, and the method can obtain CeO₂Nano materials, but processesThe process involves strong alkali substances, the regulation range is low, and the product dispersibility is poor.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides CeO with adjustable oxygen vacancy content₂The invention obviously improves the regulation of CeO by the preparation method of the nano material₂The capacity range of the oxygen vacancy content is increased, and the method can effectively regulate and control CeO₂Safety, simplicity of oxygen vacancy operation, and CeO₂Dispersibility of the product.

In order to achieve the purpose, the invention is realized by the following technical scheme:

oxygen vacancy content adjustable CeO₂The preparation method of the nano material comprises the following steps: dissolving raw materials of polyvinylpyrrolidone and cerous nitrate hexahydrate in an N, N-dimethylformamide solvent, and uniformly mixing to obtain a raw material mixture; transferring the obtained raw material mixture into a polytetrafluoroethylene lining, sealing the polytetrafluoroethylene lining by using a reaction kettle, and carrying out solvothermal reaction to obtain oxygen vacancy controllable CeO₂And (3) nano materials.

Preferably, the molecular weight of the polyvinylpyrrolidone is 10,000-1300,000.

Preferably, the solvothermal reaction temperature is 100-200 ℃.

Preferably, the solvothermal reaction time is from 1 to 30 hours.

Preferably, the mass concentration of the cerium nitrate hexahydrate dispersed in the reaction solvent is 8.3-41.66 mg/m L.

Preferably, the volume ratio of the N, N-dimethylformamide solution to the inner liner of the reaction kettle is 8:25-20: 25.

Preferably, the mass concentration of the polyvinylpyrrolidone dispersed in the reaction solvent is 0 to 35 mg/m L.

Compared with the prior art, the invention has the following beneficial effects: the invention obviously improves the CeO product₂The oxygen vacancy content is adjusted within the range, and under the dispersion action of polyvinylpyrrolidone molecules, the dispersibility of the obtained product is obviously improved, thereby being beneficial to fully exerting the CeO₂The oxygen buffering performance of nanomaterials has potential in various fields. In addition, the used regulation and control method is safe, easy to realize, simple and convenient, and can fully increase the possibility of the regulation and control method in practical application.

Drawings

FIG. 1A shows a CeO with adjustable oxygen vacancy content obtained in example 1 of the present invention₂FIG. 1B is a scanning transmission electron microscope photograph of a product obtained in the process for preparing a nanomaterial, and FIG. 1B is a photograph of a CeO having an adjustable oxygen vacancy content obtained in example 1 of the present invention₂Electron energy loss spectrogram of the product in the preparation method of the nano material;

FIG. 2 shows a CeO with adjustable oxygen vacancy content obtained in example 3 of the present invention₂Transmission electron micrographs of the product of the nanomaterial preparation process;

FIG. 3 shows that CeO with adjustable oxygen vacancy content is obtained in the embodiments 1, 2, 6 and 7 of the invention₂The product in the preparation method of the nano material has a spectrum for controlling the content of oxygen vacancies by representation.

Detailed Description

The technical scheme of the invention is further explained in detail by combining the drawings and the specific embodiments in the specification.