Composite material as well as preparation method and application thereof

Abstract

The invention discloses a composite material as well as a preparation method and application thereof. The preparation method of the composite material comprises the following steps: 1) dispersing graphene oxide in water to obtain a graphene oxide suspension; 2) adding water-soluble cerium salt into the graphene oxide suspension to obtain a first mixture solution; 3) adding C2-C10 monoamino carboxylic acid into the first mixture solution to obtain a second mixture solution; and 4) carrying out heating reaction on the second mixture solution at 60-160 DEG C to prepare the composite material. The prepared composite material is excellent in dispersity and has good polishing performance and surface enhanced Raman performance.

Description

Technical Field

[0001] The present invention relates to a composite material, a preparation method thereof, and uses thereof. Background Art

[0002] As one of the widely studied rare earth oxides, cerium oxide has excellent redox ability due to the reversible conversion between Ce 3+ and Ce 4+ Moreover, oxygen vacancies and defect structures are easily formed in the crystal structure of cerium oxide, and these defects enhance the surface reactivity of cerium oxide. More importantly, the nano-morphology of cerium oxide has flexible tunability. This makes it widely used in fields such as catalytic materials, biomedicine, fuel cells, and chemical mechanical polishing. Especially, it is widely used in chemical mechanical polishing. Since the cerium oxide abrasive has a moderate hardness and will not cause large scratches on the material surface, and cerium oxide as an abrasive has the combined effect of physical and mechanical removal and chemical action, the polishing efficiency can be greatly improved. However, cerium oxide is extremely easy to agglomerate as a single abrasive, making it difficult to exert its own advantages. Therefore, researchers have compounded cerium oxide with other materials, such as silica, polymer coating, etc., to improve its disadvantages of easy agglomeration and low chemical activity. In addition, due to the easy formation of surface defects on the surface of cerium oxide, the local electric field can be enhanced, and it can adsorb the analyte molecules as active sites to enhance the Raman signal.

[0003] CN103506617A discloses a method for growing nano-oxides on the surface of silver nanoparticles. The method includes the following steps: 1) After dispersing silver nanoparticles in water, an alkaline precipitating agent and a metal salt are added to obtain a mixed solution; 2) The mixed solution in step 1) is transferred to a hydrothermal autoclave and subjected to a hydrothermal reaction under an oxygen atmosphere. The precipitate obtained after the reaction is the silver nanoparticles with nano-oxides grown on the surface. Among them, the metal salt is selected from one of cerium salts, titanium salts, or iron salts.

[0004] CN109289849A discloses a method for controllably preparing a novel CeO 2 / Ag renewable surface-enhanced Raman active photocatalytic material. The method specifically includes the following steps: After adding CeO 2 nanorods to deionized water and stirring for 10 min, a 1 mol / L silver nitrate solution is added, and after continuing to stir for 10 min, it is irradiated with a 250 W ultraviolet light source for 2 h, then filtered, and the precipitate is washed with deionized water and ethanol, and then vacuum dried at 80°C for 12 h to obtain the cerium oxide / silver (CeO 2 / Ag) renewable surface-enhanced Raman active photocatalytic material.

[0005] CN114527110A discloses a method using Au@M@CeO 2Raman detection method for trace CO as an enhanced substrate. In this method, M = Pt, Pd, and the specific steps are as follows: (1) Synthesize core-seed Au@M core-shell structure nanoparticles; (2) After centrifugal washing, the core-seed is dispersed in a surfactant CTAB solution; (3) Prepare Au@M@CeO 2 core-shell structure nanoparticles; (4) After washing and concentrating the Au@M@CeO 2 core-shell structure nanoparticles, drop them on a clean silicon wafer; (5) Apply different reaction atmospheres for in-situ Raman spectroscopy research to detect their SERS signals; (6) Analyze and compare the SERS signals obtained in step (5) to obtain the catalytic reaction process on this multi-layer core-shell nanostructure.

[0006] All of the above composite materials are prepared by combining CeO 2 with noble metal particles, which are expensive and have a high preparation cost. Moreover, the composite material combining CeO 2 with noble metal particles is not suitable for polishing.

[0007] CN116848205A discloses a polishing slurry composition, which includes: nano cerium oxide polishing particles; and a water-soluble compound containing a hydrophilic group in the molecule. Optionally, the polishing slurry composition further includes at least one of an amphoteric compound containing an amino group and a carboxyl group in the molecule, a surfactant containing an organic acid, and a pH regulator. This polishing slurry mainly studies the components of the polishing slurry and does not synthesize new materials.

[0008] CN119409220A discloses a method for synthesizing octahedral nano cerium oxide with a high Ce 3+ ratio and a chemical mechanical polishing liquid. This polishing liquid uses the synthesized octahedral cerium oxide as an abrasive. The specific steps for preparing the octahedral cerium oxide are as follows: Dissolve a certain amount of organic ligand and cerium nitrate in deionized water, control the ratio of the organic ligand, cerium nitrate, and water at 0.01 - 0.5:1:100 - 300, and stir for 1 - 2 h under a nitrogen atmosphere; Add a certain amount of alkali solution dropwise to the solution at a certain speed under a nitrogen atmosphere, perform hydrothermal treatment on the mixture, control the reaction temperature between 80 - 150 °C, the synthesis time at 6 - 8 h, centrifuge, dry, and calcine the mixture after the reaction. The calcination temperature is 400 - 600 °C, and calcine for 4 - 8 h to obtain octahedral nano cerium oxide with a high Ce 3+ ratio with a particle size of about 30 - 50 nm. This method requires a nitrogen atmosphere.

[0009] CN117757433A discloses a cerium oxide-graphene oxide composite material and a preparation method thereof. The preparation method includes the following steps: 1) providing a graphene oxide suspension; 2) sequentially adding a water-soluble cerium salt and a dispersant to the graphene oxide suspension under stirring to obtain a first mixture; wherein, the mass ratio of graphene oxide to the water-soluble cerium salt is 1:10-500; 3) adding an alkali metal hydroxide to the first mixture to obtain a second mixture; 4) reacting the second mixture at 150-220 °C, after the reaction ends, performing solid-liquid separation, washing and drying the solid to obtain the cerium oxide-graphene oxide composite material; wherein, the particle size of the cerium oxide particles in the composite material is 10-100 nm. This method requires a higher temperature, and adding sodium hydroxide and a dispersant during the preparation process is likely to cause environmental pollution. Summary of the Invention

[0010] In view of this, an object of the present invention is to provide a preparation method of a composite material. The cerium oxide nanoparticles of the composite material prepared by this method are attached to graphene oxide in an irregular polyhedron shape and have excellent dispersibility. Another object of the present invention is to provide the composite material prepared by the above preparation method. Still another object of the present invention is to provide the use of the above composite material.

[0011] The present invention adopts the following technical solutions to achieve the above objects.

[0012] On the one hand, the present invention provides a preparation method of a composite material, including the following steps:

[0013] 1) Disperse graphene oxide in water to obtain a graphene oxide suspension;

[0014] 2) Add a water-soluble cerium salt to the graphene oxide suspension obtained in step 1) to obtain a first mixture solution; wherein, the mass ratio of the graphene oxide to the water-soluble cerium salt is 1:1-50;

[0015] 3) Add a monoamino carboxylic acid with C2-C10 to the first mixture solution obtained in step 2) to obtain a second mixture solution; wherein, the mass ratio of the monoamino carboxylic acid with C2-C10 to the water-soluble cerium salt is 1:1-20;

[0016] 4) Heat and react the second mixture solution obtained in step 3) at 60-160 °C to prepare the composite material.

[0017] According to the preparation method of the present invention, preferably, in step 1), based on 1 g of graphene oxide, the amount of water used can be 50-500 mL, preferably 100-400 mL.

[0018] In the present invention, the water used can be ultrapure water, deionized water or distilled water, preferably ultrapure water.

[0019] According to the preparation method of the present invention, preferably, in step 1), the dispersion can be carried out by ultrasonic dispersion, and the dispersion time is 10 - 60 min, more preferably 20 - 50 min. A reasonable ultrasonic dispersion time can ensure that graphene oxide is more uniformly dispersed in water.

[0020] According to the preparation method of the present invention, preferably, in step 2), the mass ratio of graphene oxide to the water-soluble cerium salt can be 1:1 - 50, more preferably 1:1 - 20.

[0021] In the present invention, limiting the ratio of graphene oxide to the water-soluble cerium salt within the above range is beneficial to the attachment of cerium oxide particles to graphene oxide in the composite material, and is also beneficial to the formation of irregular polyhedral cerium oxide nanoparticles, thereby improving the dispersibility and chemical reaction activity of the cerium oxide nanoparticles.

[0022] According to the preparation method of the present invention, preferably, the water-soluble cerium salt can be selected from at least one of cerium nitrate, cerium sulfate, cerium acetate, and cerium halide, preferably selected from at least one of cerium nitrate, cerium sulfate, cerium chloride, and cerium bromide.

[0023] In the present invention, the water-soluble cerium salt can be either an anhydrous cerium salt or a hydrated cerium salt. When the water-soluble cerium salt is a hydrated cerium salt, the mass ratio between the aforementioned graphene oxide and the water-soluble cerium salt refers to the mass ratio between graphene oxide and the cerium salt without water.

[0024] In the present invention, when adding the water-soluble cerium salt to the graphene oxide suspension obtained in step 1), the water-soluble cerium salt can be added while stirring until the solution becomes clear. This can make the water-soluble cerium salt dissolve faster and better.

[0025] The stirring can be any type of stirring method well known in the art and is not particularly limited herein. For example, but not limited to, it can be magnetic stirring.

[0026] According to the preparation method of the present invention, preferably, in step 3), the mass ratio of the C2 - C10 monoamino carboxylic acid to the water-soluble cerium salt can be 1:1 - 20, preferably 1:2 - 10.

[0027] In the present invention, limiting the ratio of the C2 - C10 monoamino carboxylic acid to the water-soluble cerium salt within the above range is beneficial to the formation of irregular polyhedral cerium oxide nanoparticles, thereby improving the dispersibility and chemical reaction activity of the cerium oxide nanoparticles.

[0028] According to the preparation method of the present invention, preferably, the C2-C10 monoaminocarboxylic acid can be a C2-C7 monoaminocarboxylic acid, and is preferably selected from at least one of 7-aminoheptanoic acid, 6-aminohexanoic acid, 5-aminopentanoic acid, γ-aminobutyric acid, alanine, and glycine.

[0029] In the present invention, a C2-C10 monoaminocarboxylic acid can also be added to the first mixture solution obtained in step 2) under heating conditions, and stirred to obtain a second mixture solution. The heating temperature can be 60-160°C, preferably 65-120°C.

[0030] According to the preparation method of the present invention, preferably, in step 4), the heating reaction temperature can be 60-160°C, preferably 65-120°C.

[0031] According to the preparation method of the present invention, preferably, in step 4), the heating reaction time can be 30-300 min, preferably 60-200 min.

[0032] Reasonable heating conditions are beneficial to the attachment of cerium oxide particles in the composite material to graphene oxide, and are also beneficial to the formation of cerium oxide nanoparticles with an irregular polyhedron shape, thereby improving the dispersibility and chemical reactivity of the cerium oxide nanoparticles.

[0033] In the present invention, the heating reaction in step 4) can be realized by any type of heating equipment known in the art, and no special limitation is made here. For example, but not limited to, an oil bath or a water bath can be used for heating.

[0034] In the present invention, after the heating reaction in step 4) is completed, it may further include steps of cooling, washing, and drying the reaction product.

[0035] The cooling can be realized by any type of cooling method known in the art, and no special limitation is made here. For example, but not limited to, natural cooling at room temperature (25°C, the same below).

[0036] The washing can be realized by any type of washing method known in the art, and no special limitation is made here. For example, but not limited to, centrifugal washing or suction filtration washing, and the washing can be ended until the pH value of the washing liquid is neutral. The washing liquid can be anhydrous ethanol or an aqueous solution of ethanol, preferably anhydrous ethanol.

[0037] The drying can be realized by any type of drying method known in the art, and no special limitation is made here. For example, but not limited to, freeze-drying.

[0038] On the other hand, the present invention also provides a composite material prepared by the above preparation method. Preferably, in the composite material, cerium oxide nanoparticles are attached to graphene oxide in an irregular polyhedron shape, and the diameter of the cerium oxide nanoparticles is 5-200 nm.

[0039] On yet another aspect, the present invention also provides the use of the above composite material in chemical mechanical polishing and surface enhanced Raman.

[0040] The preparation method of the present invention has a simple process and low cost. In the composite material prepared by the present invention, cerium oxide nanoparticles are attached to graphene oxide in an irregular polyhedron shape, with excellent dispersibility, and have good polishing performance and surface enhanced Raman performance. Description of the Drawings

[0041] Figure 1 It is the TEM image of the composite material prepared in Example 1 of the present invention.

[0042] Figure 2 It is the TEM image of the composite material prepared in Example 2 of the present invention.

[0043] Figure 3 It is the TEM image of the composite material prepared in Example 3 of the present invention.

[0044] Figure 4 It is the AFM image of the polished composite material prepared in Example 2 of the present invention.

[0045] Figure 5 It is the AFM image of the polished material without graphene oxide prepared in Comparative Example 1 of the present invention. Detailed Embodiments

[0046] The present invention will be further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0047] <Testing Methods>

[0048] TEM measurement: It is carried out using a Thermo Fisher Talos F200i transmission electron microscope.

[0049] Polishing: It is carried out using a Bruker TriboLab CMP polishing machine.

[0050] AFM measurement: The chemical mechanical polishing performance of the material is evaluated by measuring the surface roughness after polishing the crystal plane and the removal rate of the polishing material by AFM (atomic force microscope). The test is carried out using a German Bruker Dimension Icon type AFM, and the tapping mode is adopted. The probe model is a German Bruker RFESPA-75.

[0051] <Raw material description>

[0052] Unless otherwise specified, the raw materials used in the following examples are all commercially available products.

[0053] Among them, graphene oxide was purchased from Xiamen Kaina Carbon New Materials Co., Ltd.

[0054] Example 1

[0055] Preparation of composite material:

[0056] 1) Place 0.2 g of graphene oxide in 40 mL of ultrapure water and perform ultrasonic dispersion for 30 min to obtain a uniform graphene oxide suspension;

[0057] 2) Under stirring, add 0.32 g of cerium nitrate hexahydrate to the graphene oxide suspension, and continue stirring until the solution becomes clear to obtain a first mixture solution;

[0058] 3) Heat the first mixture solution to 70 °C, and at 70 °C, add 0.09 g of 6 - aminocaproic acid to the first mixture solution, stir evenly to obtain a second mixture solution;

[0059] 4) React the second mixture solution at 70 °C for 120 min. After the reaction is completed, cool it to room temperature. Filter the cooled reaction product, then use anhydrous ethanol for centrifugal washing until the pH value of the washing liquid is neutral, and then freeze - dry to obtain the composite material.

[0060] Example 2

[0061] Preparation of composite material:

[0062] 1) Place 0.2 g of graphene oxide in 40 mL of ultrapure water and perform ultrasonic dispersion for 30 min to obtain a uniform graphene oxide suspension;

[0063] 2) Under stirring, add 1.0 g of cerium nitrate hexahydrate to the graphene oxide suspension, and continue stirring until the solution becomes clear to obtain a first mixture solution;

[0064] 3) Heat the first mixture solution to 70 °C, and at 70 °C, add 0.28 g of 6 - aminocaproic acid to the first mixture solution, stir evenly to obtain a second mixture solution;

[0065] 4) React the second mixture solution at 70 °C for 150 min. After the reaction is completed, cool it to room temperature. Filter the cooled reaction product, then use anhydrous ethanol for centrifugal washing until the pH value of the washing liquid is neutral, and then freeze - dry to obtain the composite material.

[0066] Example 3

[0067] Preparation of composite material:

[0068] 1) 0.2 g of graphene oxide was placed in 40 mL of ultrapure water and ultrasonically dispersed for 30 min to obtain a uniform graphene oxide suspension;

[0069] 2) Under stirring, 2.17 g of cerium nitrate hexahydrate was added to the graphene oxide suspension, and stirring was continued until the solution became clear to obtain a first mixture solution;

[0070] 3) The first mixture solution was heated to 90 °C, and at 90 °C, 0.28 g of 6 - aminocaproic acid was added to the first mixture solution and stirred evenly to obtain a second mixture solution;

[0071] 4) The second mixture solution was reacted at 90 °C for 150 min. After the reaction, it was cooled to room temperature. The cooled reaction product was filtered, then centrifugally washed with absolute ethanol until the pH value of the washing liquid was neutral, and then freeze - dried to obtain the composite material.

[0072] Comparative Example 1

[0073] Except for the following settings, the rest are the same as in Example 2:

[0074] In this comparative example, graphene oxide was not added, and the obtained reaction product was cerium oxide.

[0075] Experimental Example 1

[0076] The composite materials prepared in Examples 1 - 3 were detected by TEM (transmission electron microscopy), and the results are as Figures 1 to 3 shown.

[0077] Figure 1 is the TEM image of the composite material prepared in Example 1. It can be seen from the image that dark - colored wrinkled graphene oxide is in the voids, and cerium oxide nanoparticles are uniformly grown on the graphene oxide. Cerium oxide presents an irregular polyhedral morphology, and the diameter of the cerium oxide nanoparticles is between 50 and 120 nm.

[0078] Figure 2 is the TEM image of the composite material prepared in Example 2. It can be clearly seen from the image that irregular polyhedral - shaped cerium oxide nanoparticles are grown on the lamellar graphene oxide, and the diameter of the cerium oxide nanoparticles is between 10 and 30 nm.

[0079] Figure 3This is a TEM image of the composite material obtained in Example 3. From the image, wrinkled graphene oxide can be seen, and cerium oxide nanoparticles are attached to the graphene oxide. The cerium oxide presents an irregular polyhedral morphology, and the diameter of the cerium oxide nanoparticles is between 20 and 100 nm.

[0080] Since the nano-cerium oxide prepared by the present invention presents an irregular polyhedral morphology, similar to tooth marks, the concave parts of the tooth marks can play a role in adsorbing the molecules to be tested, and the activity is enhanced, thereby enhancing the Raman signal.

[0081] Experimental Example 2

[0082] Twenty 2-inch silicon wafers of the same quality were used as one group, and two groups were provided in total. The materials prepared in Example 2 and Comparative Example 1 were used to polish one group of silicon wafers, respectively, and the polishing effect of each silicon wafer in each group was tested.

[0083] By comparing the polishing test of the composite material prepared in Example 2 with the pure cerium oxide material prepared in Comparative Example 1 without adding graphene oxide, it can be seen that:

[0084] The average polishing rate of the composite material prepared in Example 2 for silicon wafers is 232.93 nm / min. The surface of the polished silicon wafer is smooth and has few scratches. The AFM test results of the composite material after polishing are as follows: Figure 4 shown.

[0085] The average polishing rate of the pure cerium oxide material without graphene oxide prepared in Comparative Example 1 for silicon wafers is 95.29 nm / min. The surface of the polished silicon wafer is uneven and has many scratches. The AFM test results of the polished material are as follows: Figure 5 shown.

[0086] The present invention is not limited to the above-mentioned embodiments. Without departing from the essential content of the present invention, any deformation, improvement and substitution that can be thought of by those skilled in the art shall fall within the scope of the present invention.

Claims

1. A method for preparing a composite material, comprising the following steps: 1) dispersing graphene oxide in water to obtain a graphene oxide suspension; 2) adding a water-soluble cerium salt to the graphene oxide suspension obtained in step 1) to obtain a first mixture solution; wherein the mass ratio of the graphene oxide to the water-soluble cerium salt is 1:1 to 50; 3) adding C2-C10 monoaminocarboxylic acid to the first mixture solution obtained in step 2) to obtain a second mixture solution; wherein the mass ratio of the C2-C10 monoaminocarboxylic acid to the water-soluble cerium salt is 1:1-20; 4) The second mixture solution obtained in step 3) is heated at 60-160° C. to react to obtain a composite material.

2. The preparation method according to claim 1, characterized in that: In step 1), based on 1 g of graphene oxide, the amount of water used is 50 to 500 mL.

3. The preparation method according to claim 1, characterized in that: In step 1), the dispersion is carried out by ultrasonic dispersion, and the dispersion time is 10 to 60 minutes.

4. The preparation method according to claim 1, characterized in that: In step 2), the mass ratio of the graphene oxide to the water-soluble cerium salt is 1:1 to 20.

5. The preparation method according to claim 1, characterized in that: In step 3), the mass ratio of the C2-C10 monoaminocarboxylic acid to the water-soluble cerium salt is 1:2-10.

6. The preparation method according to claim 1, characterized in that: The water-soluble cerium salt is selected from at least one of cerium nitrate, cerium sulfate, cerium acetate and cerium halide.

7. The preparation method according to claim 1, characterized in that: The C2-C10 monoaminocarboxylic acid is a C2-C7 monoaminocarboxylic acid.

8. The preparation method according to claim 1, characterized in that: In step 4), the heating reaction time is 30 to 300 minutes.

9. A composite material obtained by the preparation method according to any one of claims 1 to 8, characterized in that: The cerium oxide nanoparticles of the composite material are in an irregular polyhedral shape and attached to the graphene oxide, and the diameter of the cerium oxide nanoparticles is 5-200nm.

10. Use of the composite material according to claim 9 in chemical mechanical polishing and surface enhanced Raman.

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