Stripping method of carbonate type nickel-aluminum double-metal hydroxide

Abstract

The invention provides a delaminating method of carbonate type nickel-aluminum double-metal hydroxide, and relates to the technical field of layered mineral materials, the delaminating method comprises the following steps: mixing a carbonate type nickel-aluminum double-metal hydroxide master batch with a saturated amino acid solution, and heating for reaction to obtain a nickel-aluminum double-metal hydroxide nanosheet. According to the method, the saturated amino acid solution is used as a raw material, the carbonate type nickel-aluminum double-metal hydroxide is directly delaminated in one step, and the tedious steps of firstly carrying out ion exchange or intercalation and then delaminating in a traditional LDHs delaminating method are avoided; and the nickel-aluminum LDHs nanosheet with a high length-diameter ratio can be obtained.

Description

Technical Field

[0001] This invention relates to the field of layered mineral materials technology, and specifically to a method for exfoliating carbonate-type nickel-aluminum bimetallic hydroxides. Background Technology

[0002] Layered double hydroxides (LDHs) are a class of anionic clay materials with a layered structure. When the anion is carbonate, the resulting LDHs are carbonate-type LDHs because CO32-... 2- Due to their strong binding force, existing technologies for preparing LDH nanosheets using carbonate-type LDHs as raw materials mainly employ a two-step or multi-step process of "pre-treatment followed by exfoliation." Specific exfoliation methods include: (1) Ion exchange-solvent stripping method This method uses large-size / weakly bound anions (such as NO3-). - ClO4 - DS - Replace CO3 2- Then, by intercalation and exfoliation with a highly polar solvent such as formamide, nanosheets can be obtained. In existing technologies, the nickel-aluminum LDHs nanosheets obtained by the above method are approximately 1.5-4.0 nm thick. This method is cumbersome, requiring two or more steps, and is time-consuming; it also uses harmful reagents; DS - Organic ions are difficult to remove; and their lateral dimensions are mostly less than 100 nm.

[0003] (2) Pretreatment-direct peeling method This method involves pretreating the precursor and then attempting direct exfoliation. While it can exfoliate nickel-aluminum LDH nanosheets, the efficiency, size, and yield are typically unsatisfactory, resulting in poor versatility. It also requires stringent parameters; the exfoliation effect is influenced by multiple factors such as pH, ionic strength, and molecular structure; and it exhibits poor reproducibility and a low success rate.

[0004] (3) Special Condition Stripping Method By utilizing special media such as supercritical fluids to weaken interlayer forces, CO2 intercalation followed by supercritical ethanol treatment under high temperature and pressure can yield LDH nanosheets with sizes up to 2µm after supercritical ethanol exfoliation. However, the process is demanding, requiring high-pressure and high-temperature equipment, resulting in high costs and difficulty in scale-up; it also suffers from low efficiency and limited exfoliation rates (studies show approximately 20%); and its effectiveness is limited for nickel-aluminum systems, especially carbonate-type nickel-aluminum LDHs.

[0005] In summary, the core bottlenecks currently facing the technology for achieving efficient and high-quality preparation of "large-sized nickel-aluminum LDH nanosheets" are: (1) the contradiction between "efficiency" and "quality": mild methods are difficult to peel off due to CO32- Strong binding force; strong methods (ultrasound, strong acid) are easy to destroy the sheet structure, resulting in fragmentation of the transverse size; (2) contradiction between "steps" and "purity": multi-step methods introduce foreign ions and solvents, resulting in low purity of the final product and easy change of composition and structure, affecting its intrinsic properties; (3) lack of "controllability" and "reproducibility": existing methods lack effective control over key parameters such as transverse size, thickness and defect density of nanosheets, resulting in poor experimental repeatability and difficulty in meeting the needs of high-end applications. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention provides a method for exfoliating carbonate-type nickel-aluminum bimetallic hydroxides. This method is characterized by mild conditions, simple process, and the ability to obtain nickel-aluminum bimetallic hydroxide nanosheets with high aspect ratios.

[0007] To achieve the above objectives, in a first aspect, the present invention provides a method for exfoliating carbonate-type nickel-aluminum bimetallic hydroxide, the method comprising: mixing carbonate-type nickel-aluminum bimetallic hydroxide masterbatch with a saturated amino acid solution, and heating the mixture to react and obtain nickel-aluminum bimetallic hydroxide nanosheets.

[0008] Preferably, the temperature of the heating reaction is 80-150°C.

[0009] Preferably, the heating reaction time is 10-60 min.

[0010] Preferably, the concentration of the saturated amino acid solution is 0.15-5 mol / L.

[0011] Preferably, the mass ratio of the carbonate-type nickel-aluminum bimetallic hydroxide to the amino acid is (0.1~1):1.

[0012] Preferably, after the heating reaction, the process further includes using a 200-700W high-energy ultrasonic probe for 10-60 seconds of ultrasonic stimulation.

[0013] Preferably, the preparation method of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch includes the following steps: mixing nickel salt, aluminum salt, and urea in deionized water to obtain a mixed solution, and heating the mixed solution to react and obtain the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch.

[0014] Preferably, the molar ratio of the nickel salt, aluminum salt, and urea is (2~4):1:6.

[0015] Preferably, the diameter of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch is greater than 500 nm.

[0016] Preferably, the aspect ratio of the carbonate-type nickel-aluminum bimetallic hydroxide nanosheets is greater than 200.

[0017] Compared with the prior art, the advantages of the present invention are as follows: The present invention uses a saturated amino acid solution as raw material to directly achieve the delamination of carbonate-type nickel-aluminum bimetallic hydroxide in one step, avoiding the cumbersome steps of traditional LDHs delamination methods, which usually require ion exchange or intercalation before delamination. The delamination method of the present invention is not only simple in process, but also can obtain nickel-aluminum LDHs nanosheets with high aspect ratio. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 The X-ray diffraction pattern of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch prepared in Example 1 of this invention; Figure 2 This is a SEM image of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch prepared in Example 1 of the present invention; Figure 3 The X-ray diffraction pattern of the nickel-aluminum bimetallic hydroxide nanosheets prepared in Example 1 of this invention; Figure 4 This is a SEM image of the nickel-aluminum bimetallic hydroxide nanosheets prepared in Example 1 of this invention; Figure 5 This is a SEM image of the nickel-aluminum bimetallic hydroxide nanosheets prepared in Example 2 of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] This invention provides a method for exfoliating carbonate-type nickel-aluminum bimetallic hydroxides (LDHs). This method uses a saturated amino acid solution as a raw material and directly exfoliates carbonate-type LDHs in one step. The exfoliation method is characterized by mild conditions, simple and efficient process, and high yield, and can obtain nickel-aluminum bimetallic hydroxide nanosheets with high aspect ratio. It solves the technical problems of cumbersome process steps, low exfoliation efficiency, and small aspect ratio of nanosheets in commonly used LDHs exfoliation methods in the prior art.

[0022] To achieve the above-mentioned technical effects, the overall concept of this invention is as follows: On one hand, the present invention provides a method for exfoliating carbonate-type nickel-aluminum bimetallic hydroxide, comprising: mixing carbonate-type nickel-aluminum bimetallic hydroxide masterbatch with a saturated amino acid solution, and heating to react to obtain the nickel-aluminum bimetallic hydroxide nanosheets.

[0023] The applicant, through extensive experimental research and analysis, determined the following delamination mechanism of the preparation method of this invention: The layers of the carbonate-type nickel-aluminum bimetallic hydroxide are positively charged, and the delamination occurs through the interlayer anions carbonate ions (CO3). 2- To maintain electroneutrality, amino acids exist as amino acid anions under alkaline conditions. Therefore, when carbonate-type nickel-aluminum bimetallic hydroxide comes into contact with amino acids, the amino acid anions utilize the CO32- present in the interlayer of the carbonate-type nickel-aluminum bimetallic hydroxide. 2- The interchangeability allows for the replacement of smaller CO3 molecules. 2- They enter the interlayer. The size of amino acid anions is much larger than that of CO3. 2- When amino acid ions enter the interlayer space, they significantly increase the interlayer spacing of nickel-aluminum bimetallic hydroxides (NiABiHOHs). Typically, the interlayer spacing of carbonate-type NiABiHOHs is 0.3-0.4 nm, but after amino acid ion intercalation, it can increase to 1.2-1.3 nm. This invention uses a saturated amino acid solution, which allows more amino acid molecules to enter the interlayer space of carbonate-type NiABiHOHs, further increasing the interlayer spacing. Simultaneously, under heating conditions, amino acid molecules can diffuse into the interlayer space more quickly, accelerating the overcoming of the energy barrier to interlayer separation. When the interlayer spacing is expanded to a certain extent, it drives the separation of carbonate-type NiABiHOH layers, forming carbonate-type NiABiHOH nanosheets.

[0024] Compared to traditional LDH stripping methods that require cumbersome steps such as ion exchange or intercalation before stripping, this invention creatively proposes a one-step stripping process using a saturated amino acid solution as a raw material under heating conditions to directly strip carbonate-type nickel-aluminum LDHs. The entire preparation process eliminates the need for organic solvents, strong acids, or strong bases, thus avoiding damage to the sheet structure and the introduction of foreign ions and solvents that could lead to low purity, altered composition, or compromised intrinsic properties of the final product. It also avoids high-temperature calcination, aligning with the principles of low carbon, energy conservation, and environmental protection. This preparation method is not only simple but also yields carbonate-type nickel-aluminum bimetallic hydroxide nanosheets with high aspect ratios (the ratio of nanosheet diameter to thickness). The nanosheets prepared using this method are approximately 1 nm thick with an aspect ratio greater than 200.

[0025] Preferably, the amino acids used in this invention are selected from 20 common amino acids that constitute natural proteins in the biological world, such as phenylalanine, methionine, threonine, tryptophan, lysine, histidine, valine, leucine, and isoleucine, etc. Due to space limitations, they are not listed here. In the embodiments of this invention, glutamic acid is the preferred amino acid. Glutamic acid, due to its anion exchangeability and steric effect as a macromolecule, unlike simple physical grinding and acid-base dissolution, can be used to prepare monolayer nanomaterials (i.e., nickel-aluminum bimetallic hydroxide nanosheets) under mild conditions.

[0026] Preferably, the heating reaction temperature is 80-150°C and the heating reaction time is 10-60 min. Under the above heating reaction conditions, the solubility of amino acids can be improved without causing them to decompose.

[0027] The present invention can prepare carbonate-type nickel-aluminum bimetallic hydroxide nanosheets under the above heating conditions. The heating time is short, the energy consumption is low, the cost is low, the equipment requirements are low, and it is easy to carry out industrial production.

[0028] Preferably, the concentration of the saturated amino acid solution used in this invention is 0.15-5 mol / L. The saturated amino acid solution is prepared by the following method: according to the concentration of 0.15-5 mol / L, weigh the corresponding mass of amino acids and the corresponding volume of deionized water. Under the condition of 80-150℃, add the amino acids to the deionized water and stir for about one minute until the amino acids are completely dissolved.

[0029] Preferably, the mass ratio of the carbonate-type nickel-aluminum bimetallic hydroxide to the amino acid is (0.1~1):1.

[0030] Preferably, the reaction further includes a post-processing step, which specifically includes centrifuging and washing the product after the reaction. The product after the reaction still contains residual unreacted amino acids. This invention uses centrifugation to separate the nanosheets from the remaining amino acids. During centrifugation, deionized water is continuously used for washing to obtain relatively pure nickel-aluminum bimetallic hydroxide nanosheets.

[0031] Preferably, the preparation method of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch includes the following steps: mixing nickel salt, aluminum salt, and urea in deionized water to obtain a mixed solution, and heating the mixed solution to react and obtain the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch. The masterbatch obtained by the above preparation method of the present invention has good crystallinity, uniform particles, and a diameter of 500 nm-1 μm. Using the above-mentioned well-crystallized masterbatch with uniform particles and a diameter of 500 nm-1 μm as raw material for exfoliation can lay the foundation for subsequently obtaining nanosheets with high aspect ratios.

[0032] Preferably, the molar ratio of the nickel salt, aluminum salt, and urea is (2-4):1:6.

[0033] Preferably, the nickel salt in the embodiments of the present invention is selected from a conventional nickel salt, such as nickel chloride, nickel nitrate, nickel sulfate, etc., and the aluminum salt is selected from a conventional aluminum salt, such as aluminum chloride, aluminum nitrate, aluminum sulfate, etc.

[0034] Preferably, the preparation method of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch further includes: after the reaction is completed, the reaction product is successively washed, dried, and ground to obtain powdered carbonate-type nickel-aluminum bimetallic hydroxide masterbatch. The solvents used for washing include deionized water and ethanol; ethanol is used to wash away excess urea, and then deionized water is used to wash the reaction product until the pH value is neutral. In this invention, room temperature drying is typically used during drying.

[0035] Preferably, the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch has a diameter greater than 500 nm. Delamination of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch with a diameter greater than 500 nm is beneficial for obtaining nanosheets with a high aspect ratio.

[0036] Preferably, the aspect ratio of the carbonate-type nickel-aluminum bimetallic hydroxide nanosheets is greater than 200.

[0037] Preferably, if a large amount of masterbatch is used, after the heating reaction, the process also includes: using a 200-700W high-energy ultrasonic probe for 10-60 seconds of ultrasonic treatment. The high-energy ultrasonic probe can generate instantaneous destructive force to peel off the stretched layers, further improving the peeling efficiency of high-concentration masterbatch. In addition, the 10-60 seconds of high-energy ultrasonic probe will not damage the nanosheet structure and will not affect the aspect ratio of the nanosheets.

[0038] In an embodiment of the present invention, a method for stripping carbonate-type nickel-aluminum bimetallic hydroxide specifically includes the following steps: (1) Preparation of carbonate-type nickel-aluminum bimetallic hydroxide masterbatch: S1. Nickel salt, aluminum salt, and urea are uniformly mixed in deionized water at a molar ratio of (2-4):1:6 to obtain the first mixed solution; S2. React the first mixed solution obtained in step S1 at 100-150℃ for 1-2 days to obtain the reaction mixture; S3. The reaction mixture is washed with ethanol and deionized water until the pH value is neutral. After filtration, drying and grinding into fine powder, carbonate-type nickel-aluminum bimetallic hydroxide masterbatch is obtained.

[0039] (2) Delamination reaction: S4. The above carbonate-type nickel-aluminum bimetallic hydroxide masterbatch is mixed with a saturated amino acid solution with a molar concentration of 0.15-5 mol / L to obtain a second mixed solution, and the second mixed solution is reacted at 80-150℃ for 10-60 min. S5. After the reaction is complete, cool to room temperature, separate the product by centrifugation, wash and dry to obtain nickel-aluminum bimetallic hydroxide nanosheets.

[0040] Secondly, the present invention also provides a nickel-aluminum bimetallic hydroxide nanosheet, which is prepared by the above-mentioned exfoliation method of carbonate-type nickel-aluminum bimetallic hydroxide.

[0041] The nickel-aluminum bimetallic hydroxide nanosheets prepared by the above-mentioned exfoliation method have a thickness of about 1 nm and an aspect ratio greater than 200. They have a high aspect ratio, can be scaled up, and are easy to store for a long time.

[0042] The following specific embodiments illustrate a method for stripping carbonate-type nickel-aluminum bimetallic hydroxides according to the present invention.

[0043] Example 1 (1) Preparation of carbonate-type nickel-aluminum bimetallic hydroxide masterbatch: S1. Add 0.7131g of nickel dichloride hexahydrate, 0.362g of aluminum chloride hexahydrate, and 0.631g of urea to 300mL of deionized water and mix evenly to obtain a mixture; S2. Heat the mixture obtained in step S1 to 100°C and react at 100°C for 2 days; S3. The obtained reaction mixture is washed with ethanol and deionized water until the pH value is neutral, then dried at room temperature and ground into a fine powder to obtain carbonate-type nickel-aluminum bimetallic hydroxide masterbatch.

[0044] (2) Delamination reaction: S4. Take 50 mg of the above carbonate-type nickel-aluminum bimetallic hydroxide masterbatch and 0.18 g of glutamic acid powder and add them to 10 mL of deionized water to obtain a mixed solution. Allow the mixed solution to react fully at 80 °C for 15 min. S5. After the reaction is complete, cool to room temperature, wash away the remaining glutamic acid with deionized water, and separate, wash and dry to obtain nickel-aluminum bimetallic hydroxide nanosheets.

[0045] Example 2 The only difference between Example 2 and Example 1 is that: Step S4: Take 60 mg of the above carbonate-type nickel-aluminum bimetallic hydroxide masterbatch and 0.18 g of glutamic acid powder and add them to 10 mL of deionized water to obtain a mixed solution. Allow the mixed solution to react fully at 80°C for 30 min.

[0046] The remaining steps are the same as in Example 1.

[0047] Example 3 The only difference between Example 3 and Example 1 is that: Step S4: Take 80 mg of the above carbonate-type nickel-aluminum bimetallic hydroxide masterbatch and 0.18 g of glutamic acid powder and add them to 10 mL of deionized water to obtain a mixed solution. Allow the mixed solution to react fully at 100°C for 30 min, and then use a 500 W high-energy ultrasonic probe to sonicate for 30 s.

[0048] The remaining steps are the same as in Example 1.

[0049] The carbonate-type nickel-aluminum bimetallic hydroxide masterbatch and nickel-aluminum bimetallic hydroxide nanosheets obtained in Example 1 were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results are as follows: Figures 1-4 As shown.

[0050] Figure 1 The X-ray diffraction pattern of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch of Example 1 of this invention is shown below. Figure 1 It can be seen that the 003 peak at 11.63° is a typical first peak of carbonate-type LDH. The results show that no other impurity peaks appeared, indicating that carbonate-type nickel-aluminum bimetallic hydroxide masterbatch was prepared in Example 1 of this invention.

[0051] Figure 2 This is a SEM image of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch from Example 1 of the present invention. Figure 2 It can be seen that the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch sample has good crystallization, with uniform particles and a diameter of 500nm-1μm.

[0052] Figure 3The X-ray diffraction pattern of the nickel-aluminum bimetallic hydroxide nanosheets of Example 1 of this invention is shown below. Figure 3 It can be seen that the characteristic peaks of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch disappeared, and a very regular quadruple diffraction peak appeared, indicating that the obtained nanosheets were uniformly and orderly stacked after peeling. The first peak of the nanosheet stacking was at 6.92°, indicating that the spacing was wider than the masterbatch interlayer spacing (0.76 nm), about 1.27 nm. The size of glutamic acid molecules is 0.8-1.2 nm, suggesting that glutamic acid molecules were attached to the nanosheets after peeling.

[0053] Figure 4 This is a SEM image of the nickel-aluminum bimetallic hydroxide nanosheets from Example 1 of the present invention. Figure 4 As can be seen, the nanosheets are very thin, about 1 nm thick, and have a diameter of 220-530 nm. Based on the fact that the aspect ratio of a nanosheet is equal to the ratio of its thickness to its diameter, the aspect ratio of the nanosheets obtained in Example 1 is 220-530.

[0054] from Figure 2 and Figure 4 Comparison also shows that the nanosheets are thinner than the masterbatch. This further illustrates that the present invention achieves the exfoliation of carbonate-type nickel-aluminum bimetallic hydroxide in a one-step process using a saturated amino acid solution, obtaining nanosheets with an aspect ratio greater than 200. The preparation method of the present invention is simple, and the obtained nanosheets have a complete structure and a high aspect ratio; therefore, it can be applied to large-scale production.

[0055] The nickel-aluminum bimetallic hydroxide nanosheets obtained in Example 2 were analyzed by SEM, and the results were as follows: Figure 5 The SEM image shown. From Figure 5 It can be seen that the nanosheet is approximately 1 nm thick and has a diameter of 210-520 nm. Based on the fact that the aspect ratio of a nanosheet is equal to the ratio of its thickness to its diameter, the aspect ratio of the nanosheet obtained in Example 2 is 210-520.

[0056] Preliminary analysis of the nickel-aluminum bimetallic hydroxide nanosheets obtained in Example 3 showed that the nanosheets obtained in Example 3 had a thickness of approximately 1 nm and a diameter of 200-500 nm. Based on the fact that the aspect ratio of a nanosheet is equal to the ratio of its thickness to its diameter, the aspect ratio of the nanosheets obtained in Example 3 is 200-500.

[0057] Therefore, the above-mentioned exfoliation method for carbonate-type nickel-aluminum bimetallic hydroxides can achieve the exfoliation of carbonate-type nickel-aluminum bimetallic hydroxides in one step using a saturated amino acid solution, and can also obtain nickel-aluminum bimetallic hydroxide nanosheets with an aspect ratio greater than 200.

[0058] It should be noted that, in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0059] This invention is not limited to the embodiments described above. Those skilled in the art can make various improvements and refinements without departing from the principles of this invention, and these improvements and refinements are also considered within the scope of protection of this invention. Contents not described in detail in this specification are prior art known to those skilled in the art.

Claims

1. A method for stripping carbonate-type nickel-aluminum bimetallic hydroxides, characterized in that, The peeling method includes: mixing carbonate-type nickel-aluminum bimetallic hydroxide masterbatch with a saturated amino acid solution, and heating the mixture to obtain nickel-aluminum bimetallic hydroxide nanosheets.

2. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, The temperature of the heating reaction is 80-150℃.

3. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, The heating reaction time is 10-60 min.

4. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, The concentration of the saturated amino acid solution is 0.15-5 mol / L.

5. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, The mass ratio of the carbonate-type nickel-aluminum bimetallic hydroxide to the amino acid is (0.1~1):

1.

6. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, After the heating reaction, the process also includes 10-60 seconds of ultrasound stimulation using a high-energy ultrasonic probe of 200-700W.

7. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, The preparation method of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch includes the following steps: mixing nickel salt, aluminum salt, and urea in deionized water to obtain a mixed solution, and heating the mixed solution to react and obtain the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch.

8. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 7, characterized in that, The molar ratio of the nickel salt, aluminum salt, and urea is (2~4):1:

6.

9. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, The diameter of the carbonate-type nickel-aluminum bimetallic hydroxide masterbatch is greater than 500 nm.

10. The method for stripping carbonate-type nickel-aluminum bimetallic hydroxides as described in claim 1, characterized in that, The aspect ratio of the carbonate-type nickel-aluminum bimetallic hydroxide nanosheets is greater than 200.

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