CN106904649B - In-situ control method for form and crystal face of nano cerium oxide - Google Patents
In-situ control method for form and crystal face of nano cerium oxide Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F17/00—Compounds of rare earth metals
- C01F17/20—Compounds containing only rare earth metals as the metal element
- C01F17/206—Compounds containing only rare earth metals as the metal element oxide or hydroxide being the only anion
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
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- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B1/00—Single-crystal growth directly from the solid state
- C30B1/02—Single-crystal growth directly from the solid state by thermal treatment, e.g. strain annealing
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- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/16—Oxides
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
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- C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
Abstract
An in-situ control method for the form and crystal face of nano cerium oxide, belonging to the technical field of rare earth nano materials. Organic alcohol is used as a dispersing agent, and the nano template is dispersed and sheared by combining a cavitation effect. Alkaline substances are used as a cerium source precipitator, the size of the nano template and the aggregation state of the nano template in a reaction system are controlled by adjusting the viscosity and the surface tension of a dispersing agent, so that a cerium precursor is adsorbed on the surface of the nano template and grows in a preferred orientation mode, the growth speed of each crystal face of cerium oxide is finally regulated, and the regulation of the form and the crystal face of the cerium oxide in the nano size range is realized. The preparation method has the advantages of simple preparation process, mild reaction conditions and easily obtained reaction raw materials, and because no surfactant is added, and the added nano template has no residue and consumes partial oxygen after calcination and oxidation, the pure cerium oxide can be obtained, and the oxygen vacancy concentration of the cerium oxide can be increased, so that the application prospect is wide.
Description
Technical Field
The invention relates to a preparation method in the technical field of rare earth nano materials, in particular to a method for controlling the form and crystal face of nano cerium oxide in situ by combining solvothermal reaction with a nano template.
Background
The nano-structured cerium oxide has unique redox activity and excellent oxygen storage and release performance, so that the nano-structured cerium oxide can be widely applied to the related catalytic technical fields of automobile exhaust purification, organic wastewater degradation, polishing materials, methane and carbon dioxide reforming and the like. The redox ability of the nano cerium oxide is closely related to the factors such as the microstructure, the crystal active surface, the dispersibility, the purity and the like of the nano cerium oxide. Cerium oxides with different geometries usually expose different crystal active surfaces (e.g., (111), (110), or (100)), making their catalytic properties significantly different. Therefore, the regulation and control of the form and crystal face of the nano cerium oxide are very important.
The existing literature search shows that the main methods for preparing the nano cerium oxide include an electrochemical deposition method, a chemical precipitation method, a micro-emulsion method, a sol-gel method, a hydrothermal/solvothermal method and the like. W, Shen et al, in Chinese Journal of Catalysis (Chinese edition) 2013, volume 34, pages 5, 838 to 850, published in the name of Tuning the shape of cerium nanoparticles for catalytic applications (morphology regulation and catalytic application of cerium oxide nanomaterials), reviewed the influence of the method for regulating the morphology and size of the cerium oxide nanoparticles on the active crystal faces and the application fields thereof. T. Taniguchi et al, Advanced Powder Technology, 2016, No. 1, pp.64 to 71, Facet control of ceria nanocrystals synthesized by an olea cooled-modified hydrotherm method (preparation of cerium oxide nanocrystals with controlled crystal planes by an oleate-mediated hydrothermal method). D. Zhang et al, Materials Letters 2008, vol 62, 23: pages 3821 to 3823, published "Solvothermal synthesis of nitrile-like carbon nanotubes/ceria composites" (hydrothermal synthesis of branched carbon nanotubes/cerium oxide composites), cerium oxide having a size of about 100 nm was prepared by a hydrothermal method using carbon nanotubes as a template and dimethylformamide and ethanol as auxiliary solvents. The three articles have studied and reviewed the relationship between the form of nano-cerium oxide and the crystal active surface and catalytic activity, indicating that the preferred method for regulating the form and exposed crystal face type of nano-cerium oxide particles is hydrothermal/solvothermal, with the aid of the auxiliary action of surfactants or templates. However, since the hydrothermal/solvent method is used to adjust the form of the nano cerium oxide, toxic or expensive additives and surfactants are often used, and high temperature and high pressure and long-time treatment are required, the green and environment-friendly practical requirements for preparing nano materials cannot be met; on the other hand, the new functional group introduced in the preparation process of the method is not easy to be completely removed, which causes interference to the performance of the nano cerium oxide and limits the practical application field of the nano cerium oxide.
Disclosure of Invention
The invention aims to provide an in-situ control method of the form and crystal face of nano cerium oxide, aiming at the defects, and the form and crystal face of the nano cerium oxide are adjusted by using dispersed and sheared carbon nano tubes, graphene and the like as nano templates.
The purpose of the invention is realized by the following technical scheme.
A method for controlling the form and crystal face of nano cerium oxide in situ sequentially comprises the following steps:
step one, dispersing 1-20 mg of nano template (carbon nano tube or graphene) in 50-150 mL of methanol, ethanol or ethylene glycol by using ultrasonic waves, and obtaining the dispersed and sheared nano template after 8-12 h; a small amount of deionized water is utilized to completely dissolve the cerium nitrate or the cerium chloride to obtain 1-10 mol L of cerium nitrate or cerium chloride-1A cerium source solution;
step two, adding the nano template in the step one into a cerium source solution, injecting an alkaline precipitator (ammonia water, sodium hydroxide and urea) into the system, and adjusting the pH value of the system to 8-11; then placing the cerium precursor in a polytetrafluoroethylene reaction kettle for solvothermal reaction at the reaction temperature of 120 ℃ and 200 ℃ for 5-48 h, and then carrying out vacuum freeze drying at the drying temperature of-40 ℃ to-60 ℃ for 15-24 h under the vacuum pressure of 40-55 Pa to obtain a cerium precursor deposited on the nano template;
and step three, placing the cerium precursor in the step two in air or oxygen atmosphere for heat treatment, wherein the heating rate is 10 ℃/min, the heat treatment temperature is 400-.
The invention takes organic alcohol as a dispersing agent, utilizes the cavitation effect to disperse and shear a nano template (carbon nano tube or graphene) and takes the nano template as a shape and crystal face regulator. Alkaline substances are used as a cerium source precipitator, the size of the nano template and the aggregation state of the nano template in a reaction system are controlled by adjusting the viscosity and the surface tension of a dispersing agent, so that a cerium precursor is adsorbed on the surface of the nano template and grows in a preferred orientation mode, the growth speed of each crystal face of cerium oxide is finally regulated, and the regulation of the form and the crystal face of the cerium oxide in the nano size range is realized. The nucleation of the cerium precursor is facilitated at a solid-liquid interface (the interface of the nano template and the system solution), and the cerium precursor is facilitated to be loaded due to the small size and the large specific surface area of the nano template. The ethylene glycol has larger viscosity and lower specific surface energy, can ensure that the carbon nanotube tube bundle is fluffy and dispersed, can effectively adsorb cerium precursor, and plays a decisive role in the anisotropic growth of the crystal. In addition, methanol, ethanol and glycol have hydrophilicity due to the hydroxyl group and can be mixed with water, so that the oil/water microreactor can be formed by the methanol, the ethanol and the glycol and a small amount of water, and the growth direction of the cerium precursor can be adjusted in a reaction system. The boiling points of the methanol and the ethanol are lower than that of the water, so that the hard agglomeration degree of the powder can be effectively relieved, and the form of the product can be controlled.
The invention adopts the nano template as a morphology regulator, and can realize in-situ regulation by utilizing solvothermal to prepare the nano cerium oxide with different morphologies and crystal faces. At present, the main method for regulating and controlling the form and crystal face of nano cerium oxide is a hydrothermal/solvothermal method, and the method mainly adopts a surfactant as an auxiliary agent, introduces a new functional group and influences the full play of the performance of the cerium oxide. On one hand, the characteristics of the boiling point, the viscosity, the specific surface energy and the like of methanol, ethanol or ethylene glycol in the solvothermal process are utilized to intervene the nucleation and growth speed of the crystal face of the cerium precursor; on the other hand, a nucleation center is provided for the cerium precursor by utilizing the nano template, the anisotropic growth of the cerium precursor on the surface or the periphery of the nano template is subjected to micro regulation, then, oxidizing atmosphere is introduced into a high-temperature reaction zone to oxidize and remove the nano template, so that the nano cerium oxide with controllable shapes (such as a tetragonal body, a cubic body, a hexagonal body and the like) and main crystal faces ((111), (100)) is obtained, and as partial oxygen is consumed by removing the nano template, the oxygen vacancy concentration of the cerium oxide is increased, and the oxygen storage/release capacity of the cerium oxide is improved.
The invention has the following beneficial effects: the invention controls the anisotropic growth direction of the cerium precursor by adjusting the distribution state of the nano template in the organic alcohol, thereby achieving the purpose of adjusting the form and crystal face of the nano cerium oxide. In order to obtain pure nano cerium oxide and improve the oxygen vacancy concentration, oxidizing atmosphere can be introduced to oxidize the nano template. The method has the advantages of simple and feasible process, easily obtained raw materials, mild reaction and simple preparation process, and can regulate and control the preparation of the nano cerium oxide with different forms (such as tetragonal, cubic and hexagonal) and main crystal faces ((111) and (100)) by regulating factors such as a nano template, a dispersing agent, an alkaline precipitator and the like according to requirements.
Drawings
FIG. 1 is a transmission electron micrograph of (a) example 1, (b) example 2, (c) example 3 and (d) example 4 of the different crystal plane nano cerium oxide prepared in the figure.
Detailed Description
The present embodiment is implemented on the premise of the technical solution of the invention, and a detailed implementation manner and a process are given, but the scope of the invention is not limited to the following embodiments.
Example 1.
Dispersing 5 mg of carbon nanotubes in 100 mL of ethylene glycol by using ultrasonic waves, and obtaining the dispersed and sheared carbon nanotubes after 15 hours; in addition, cerium salt solution with the concentration of 0.5 mol/L is prepared; adding the dispersed and sheared carbon nano tubes into a cerium salt solution, and simultaneously dropwise adding an alkaline precipitator to adjust the pH value of the system to 9; transferring the mixed solution into a polytetrafluoroethylene reaction kettle to carry out solvothermal reaction at the reaction temperature of 160 ℃ for 12 h, cooling, and then carrying out vacuum freeze drying at the drying temperature of-45 ℃, the drying time of 15 h and the vacuum pressure of 40 Pa to obtain a carbon nano tube/cerium precursor compound; and (2) placing the carbon nano tube/cerium precursor compound in a magnetic boat, pushing the magnetic boat to the central area of a corundum reaction tube in a horizontal tube furnace, introducing oxygen and carrying out heat treatment along with the oxygen, wherein the temperature rise speed is 5 ℃/min, the heat treatment temperature is 600 ℃, the heat treatment time is 0.5 h, and cooling to the normal temperature to obtain the pure nano cerium oxide with the square shape and the main crystal plane of (100).
Example 2.
Dispersing 10 mg of carbon nano tubes in 150 mL of ethanol by using ultrasonic waves, and obtaining the dispersed and sheared carbon nano tubes after 15 hours; in addition, cerium salt solution with the concentration of 0.1 mol/L is prepared; adding the dispersed and sheared carbon nano tubes into a cerium salt solution, and simultaneously dropwise adding an alkaline precipitator to adjust the pH value of the system to 9.5; transferring the mixed solution into a polytetrafluoroethylene reaction kettle to carry out solvothermal reaction at the reaction temperature of 160 ℃ for 24 hours, cooling, and then carrying out vacuum freeze drying at the drying temperature of-50 ℃, the drying time of 20 hours and the vacuum pressure of 45 Pa to obtain a carbon nano tube/cerium precursor compound; and (2) placing the carbon nano tube/cerium precursor compound in a magnetic boat, pushing the magnetic boat to the central area of a corundum reaction tube in a horizontal tube furnace, introducing oxygen and carrying out heat treatment along with the oxygen, wherein the temperature rise speed is 5 ℃/min, the heat treatment temperature is 600 ℃, the heat treatment time is 1 h, and cooling to the normal temperature to obtain pure nano cerium oxide with the shape of a cube and a main crystal plane of (100).
Example 3.
Dispersing 5 mg of graphene in 100 mL of ethylene glycol by using ultrasonic waves, and obtaining a uniformly dispersed graphene ethylene glycol suspension after 12 hours; in addition, cerium salt solution with the concentration of 0.5 mol/L is prepared; adding the graphene glycol suspension into a cerium salt solution, and simultaneously dropwise adding an alkaline precipitator to adjust the pH value of the system to 10; transferring the mixed solution into a polytetrafluoroethylene reaction kettle to carry out solvothermal reaction at the reaction temperature of 180 ℃ for 24 hours, cooling, and then carrying out vacuum freeze drying at the drying temperature of-55 ℃, the drying time of 25 hours and the vacuum pressure of 50 Pa to obtain a graphene/cerium precursor compound; and (2) placing the carbon nano tube/cerium precursor compound in a magnetic boat, pushing the magnetic boat to the central area of a corundum reaction tube in a horizontal tube furnace, introducing air, carrying out heat treatment at the heating speed of 10 ℃/min and the heat treatment temperature of 600 ℃ for 0.5 h, and cooling to normal temperature to obtain the pure nano cerium oxide with the hexagonal body and the main crystal plane (111).
Example 4.
Dispersing 15 mg of graphene in 150 mL of ethanol by using ultrasonic waves, and obtaining uniformly dispersed graphene ethanol suspension after 12 hours; in addition, cerium salt solution with the concentration of 0.5 mol/L is prepared; adding the graphene ethanol suspension into a cerium salt solution, and simultaneously dropwise adding an alkaline precipitator to adjust the pH value of the system to 11; transferring the mixed solution into a polytetrafluoroethylene reaction kettle to carry out solvothermal reaction at the reaction temperature of 180 ℃ for 12 h, cooling, and then carrying out vacuum freeze drying at the drying temperature of-55 ℃, the drying time of 20 h and the vacuum pressure of 55 Pa to obtain a graphene/cerium precursor compound; and (2) placing the carbon nano tube/cerium precursor compound in a magnetic boat, pushing the magnetic boat to the central area of a corundum reaction tube in a horizontal tube furnace, introducing air, carrying out heat treatment along with the air, cooling to normal temperature to obtain pure nano cerium oxide with the hexagonal body and the main crystal plane (111), wherein the heating rate is 10 ℃/min, the heat treatment temperature is 600 ℃, and the heat treatment time is 2 hours.
Claims (2)
1. A method for controlling the form and crystal face of nano cerium oxide in situ is characterized in that: the method sequentially comprises the following steps:
step one, dispersing 1-20 mg of nano template in 50-150 mL of methanol, ethanol or ethylene glycol by using ultrasonic waves, and obtaining the dispersed and sheared nano template after 8-12 h; a small amount of deionized water is utilized to completely dissolve the cerium nitrate or the cerium chloride to obtain 1-10 mol L of cerium nitrate or cerium chloride-1A cerium source solution;
step two, adding the nano template in the step one into a cerium source solution, injecting an alkaline precipitator into the system, and adjusting the pH value of the system to 8-11; then placing the cerium precursor in a polytetrafluoroethylene reaction kettle for solvothermal reaction at the reaction temperature of 120 ℃ and 200 ℃ for 5-48 h, and then carrying out vacuum freeze drying at the drying temperature of-40 ℃ to-60 ℃ for 15-24 h under the vacuum pressure of 40-55 Pa to obtain a cerium precursor deposited on the nano template;
thirdly, placing the cerium precursor in the second step in air or oxygen atmosphere for heat treatment, wherein the heating rate is 10 ℃/min, the heat treatment temperature is 400-;
in the first step, the nano template is a carbon nano tube or graphene.
2. The method for controlling the form and crystal face of nano cerium oxide according to claim 1, wherein the method comprises the following steps: in the second step, the alkaline precipitator is one of ammonia water, sodium hydroxide or urea.
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| CN108767280B (en) * | 2018-06-22 | 2020-10-27 | 西安交通大学 | Pt nanoparticle/hydroxyl cerite nanocluster/graphene composite material and preparation method thereof |
| CN108786786B (en) * | 2018-07-17 | 2021-01-01 | 河南科技大学 | Nano MoO for photocatalytic degradation3Method for preparing powder |
| CN109082329B (en) * | 2018-07-23 | 2021-04-20 | 江苏大学 | Ternary nano self-lubricating composite material and preparation method thereof |
| CN109589956B (en) * | 2018-12-26 | 2021-11-23 | 江苏大学 | Preparation method and application of defect-rich metal oxide |
| CN112939052B (en) * | 2021-03-22 | 2022-12-09 | 北方稀土生一伦高科技有限公司 | Preparation method of small-particle-size cerium oxide |
| CN113104880A (en) * | 2021-05-07 | 2021-07-13 | 江西理工大学 | Yttrium oxide microsphere composed of nano rod-shaped structure and preparation method thereof |
| CN114477264A (en) * | 2022-03-03 | 2022-05-13 | 赣州湛海新材料科技有限公司 | Method for preparing nano cerium oxide by sol-gel method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1704339A (en) * | 2004-06-03 | 2005-12-07 | 中南大学 | Process for preparing high purity active nano ceria |
| CN101407331A (en) * | 2008-10-30 | 2009-04-15 | 上海大学 | Method of preparing cerium oxide nano-plate |
| CN105255446A (en) * | 2015-11-06 | 2016-01-20 | 安徽理工大学 | Reduced graphene oxide and nano cerium oxide composite microwave absorbing material and preparation method thereof |
-
2017
- 2017-03-08 CN CN201710133479.XA patent/CN106904649B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1704339A (en) * | 2004-06-03 | 2005-12-07 | 中南大学 | Process for preparing high purity active nano ceria |
| CN101407331A (en) * | 2008-10-30 | 2009-04-15 | 上海大学 | Method of preparing cerium oxide nano-plate |
| CN105255446A (en) * | 2015-11-06 | 2016-01-20 | 安徽理工大学 | Reduced graphene oxide and nano cerium oxide composite microwave absorbing material and preparation method thereof |
Non-Patent Citations (3)
| Title |
|---|
| Carbon nanotube assisted synthesis of CeO2 nanotubes;Dengsong Zhang et al.;《Journal of Solid State Chemistry》;20061223;第180卷;第654-660页 * |
| Carbon nanotube assisted sythesis and high catalytic activity of CeO2 hollow nanobeads;Dengsong Zhang et al.;《Materials chemistry and physics》;20080923;第113卷;第527-530页 * |
| Preparation of Metal Oxide Nanofilms Using Graphene Oxide as a Template;Sakae Takenaka et al.;《J. Phys. Chem. C》;20150518;第119卷;第12445−12454页 * |
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