EDTA (ethylene diamine tetraacetic acid) intercalated MgAl-LDH (layered double hydroxide) nanosheet material and method

Abstract

The invention discloses an EDTA (ethylene diamine tetraacetic acid) intercalated MgAl-LDH (layered double hydroxide) nanosheet material and a method, and belongs to the field of carbon fiber modified materials. The preparation method comprises the following steps: dissolving Mg (NO3) 2 and Al (NO3) 3 in water to form a mixed solution; adjusting the pH value of the mixed solution to 11 by using a NaOH solution; carrying out aging treatment on the mixed solution of which the pH is adjusted at 80 DEG C for 2 hours to form an MgAl-LDH nanosheet; then, EDTA is used for adjusting the pH value of the solution to 5.5, an ion exchange reaction is carried out, and an EDTA intercalation enters the MgAl-LDH structure; and after the reaction is completed, washing a reaction product with water, and drying to obtain the MgAl-LDH nanosheet material of the EDTA intercalation. The interlayer spacing of LDH is changed through EDTA intercalation, so that the material can meet the application requirements in the fields of electrochemistry and electrocatalysis, and the preparation method is simple in process and low in manufacturing cost and has wide application prospects in the aspect of large-scale production.

Description

Technical Field

[0001] The invention belongs to the field of carbon fiber modified materials, and in particular relates to a MgAl-LDH nanosheet material and a method which takes a carbon fiber material as a substrate and loads an EDTA intercalation layer. Background Art

[0002] In modern society, the rapid development of renewable energy has made energy storage technology essential. Renewable energy sources such as solar and wind energy have inherent intermittent and unstable characteristics, which poses challenges to the transmission and use of energy. In order to effectively integrate and balance energy supply, energy storage systems have become the core of achieving sustainable energy utilization. However, in the field of energy storage and conversion, the application of traditional materials generally has not shown good results. Traditional materials have a series of limitations such as low energy density, weak catalytic activity and short service life. Therefore, it is necessary to find a new, environmentally friendly new material to meet these challenges and provide a more reference solution for the design of new materials in the future.

[0003] Carbon fiber materials have the characteristics of light weight and high strength, and also have good electrical conductivity and chemical stability. This composite material not only retains the high conductivity and porous structure of carbon felt, but also has broad application prospects in various fields such as materials, electrocatalysis, capacitors, etc. by virtue of the large interlayer spacing and abundant surface active sites of LDH nanosheets. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects in the prior art and provide a MgAl-LDH nanosheet material and method with simple process and low cost through EDTA intercalation. By changing the interlayer spacing of LDH through EDTA intercalation, the material can meet the application requirements in the field of electrochemistry and electrocatalysis. The preparation method of the present invention involves a simple process, low production cost, and has broad application prospects in large-scale production.

[0005] The specific technical solutions adopted by the present invention are as follows:

[0006] In a first aspect, the present invention provides an EDTA-intercalated MgAl-LDH nanosheet material, which uses MgAl-LDH as a substrate and expands the interlayer spacing of MgAl-LDH through EDTA intercalation.

[0007] Preferably, the MgAl-LDH interlayer spacing can be expanded to above.

[0008] In a second aspect, the present invention provides a method for preparing an EDTA-intercalated MgAl-LDH nanosheet material, which is as follows:

[0009] Mg(NO3)2 and Al(NO3)3 are dissolved in water to form a mixed solution; the pH value of the mixed solution is adjusted to 11 with a NaOH solution; the mixed solution after the pH adjustment is aged at 80°C for 2 hours to form MgAl-LDH nanosheets; the pH value of the solution is then adjusted to 5.5 with EDTA, and an ion exchange reaction is performed to allow EDTA to be intercalated into the MgAl-LDH structure; after the reaction is completed, the reaction product is washed with water, and after drying, an EDTA-intercalated MgAl-LDH nanosheet material is obtained.

[0010] Preferably, in the mixed solution, the molar ratio of Mg(NO3)2 to Al(NO3)3 is 2:1.

[0011] Preferably, the ion exchange reaction time is 4-12 hours.

[0012] Preferably, the drying temperature is 40-60° C., and the drying time is 12-24 hours.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) The preparation method involves simple processes, low production costs, and has broad application prospects in large-scale production.

[0015] (2) The carbon fiber material prepared by the present invention has more abundant active sites and larger internal interlayer spacing through LDH loading and EDTA modification, and can be widely used in various wearable electronic products such as sensors, conductive fabrics, and flexible materials.

[0016] (3) The carbon fiber material prepared by the present invention has a larger LDH interlayer spacing, which overcomes the shortcomings of low permeability of traditional LDH and low ion transmission rate due to the inability of larger molecules to pass through the internal space of the material, while achieving high specific surface area and abundant active sites, and can be widely used as an important material basis in the fields of electrochemistry and electrocatalysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the SEM scanning electron microscope image of EDTA@LDH material;

[0018] Figure 2 X-ray diffraction (XRD) patterns of LDH and EDTA@LDH. DETAILED DESCRIPTION

[0019] The present invention is further described and illustrated below in conjunction with the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly without conflicting with each other.

[0020] The present invention provides an EDTA intercalated MgAl-LDH nanosheet material, which uses MgAl-LDH as a substrate and expands the interlayer spacing of MgAl-LDH through EDTA intercalation. The material obtained by the present invention realizes rapid conduction and diffusion of ions inside the material and improves the ion transmission rate by modifying the interlayer spacing and optimizing the interlayer structure.

[0021] As a preferred embodiment of the present invention, the internal interlayer spacing of the material can be expanded to above.

[0022] For the above-mentioned EDTA intercalated MgAl-LDH nanosheet material, the present invention also provides a preparation method, which is specifically as follows:

[0023] Mg(NO3)2 and Al(NO3)3 are dissolved in deionized water and stirred on a magnetic stirrer (for example, for 10 hours) to form a mixed solution. The pH value of the mixed solution is adjusted to 11 with a NaOH solution. The mixed solution after pH adjustment is aged for 2 hours at 80°C to form MgAl-LDH nanosheets. Subsequently, the pH value of the above solution is adjusted to 5.5 with EDTA, and an ion exchange reaction is performed to allow EDTA to be intercalated into the MgAl-LDH structure to expand its internal interlayer distance. After the ion exchange reaction is completed, the reaction product is washed with deionized water, and after drying, an EDTA-intercalated MgAl-LDH nanosheet material is obtained, which further stabilizes the structure of the material and improves its conductivity and stability.

[0024] As a preferred embodiment of the present invention, in the mixed solution, the molar ratio of Mg(NO3)2 and Al(NO3)3 is 2: 1. Mg(NO3)2 and Al(NO3)3 are dissolved in a molar ratio of 2: 1, which is achieved by stirring to ensure the uniformity of the solution.

[0025] As a preferred embodiment of the present invention, the ion exchange reaction time is 4-12 hours to ensure that EDTA is fully intercalated.

[0026] As a preferred embodiment of the present invention, the drying is carried out in a vacuum drying oven at a drying temperature of 40-60°C for 12-24 hours to ensure complete drying of the product. In this embodiment, the drying can be carried out at 40°C for 10-12 hours.

[0027] The following examples will further illustrate the preparation method of the present invention and the properties of the obtained material.

[0028] Example

[0029] In this embodiment, an EDTA-intercalated MgAl-LDH nanosheet material is prepared, and the preparation method is as follows:

[0030] First, Mg(NO3)2 and Al(NO3)3 were dissolved in deionized water at a molar ratio of 2:1, and the pH was adjusted to 11 with NaOH. After mixing evenly, the mixture was aged at 80°C for 2 hours to form MgAl-LDH nanosheets. Next, the pH of the solution was adjusted to 5.5 with EDTA, and an ion exchange reaction was performed for 8 hours to intercalate EDTA into the MgAl-LDH structure. After the reaction was completed, the mixture was washed with deionized water and vacuum dried at 40°C for 12 hours to obtain the modified material (EDTA@LDH).

[0031] The results are as follows:

[0032] Figure 1 This is a scanning electron microscope (SEM) image of EDTA@LDH, which shows the layered double hydroxide (LDH) nanosheets intercalated with EDTA on the surface of carbon fiber.

[0033] Figure 2 The XRD patterns of two materials are shown, where LDH represents layered double hydroxide and EDTA@LDH represents EDTA intercalated layered double hydroxide obtained in Example 1. The red vertical line at the bottom represents the characteristic peak position in the PDF#35-0964 standard card for comparative analysis.

[0034] LDH (layered double hydroxide): The spectrum shows multiple sharp diffraction peaks, which correspond to the crystal structure of layered double hydroxide. The positions and intensities of these peaks indicate that LDH has a highly ordered layered structure.

[0035] EDTA@LDH (EDTA intercalated layered double hydroxide): Compared with pure LDH, some new peaks (marked with asterisks) appeared in the spectrum of EDTA@LDH, indicating that EDTA intercalation led to a change in the interlayer spacing. In addition, the spectrum of EDTA@LDH also contains the characteristic peaks of LDH, indicating that the intercalation process did not completely destroy the crystal structure of LDH.

[0036] The preparation method of the invention is simple and efficient, and the prepared EDTA@LDH material has a uniform layered structure and good chemical stability. The material has broad application prospects in various fields such as electrode materials, electrocatalysis, capacitors, etc.

[0037] The above-described embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. A person skilled in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. An EDTA intercalated MgAl-LDH nanosheet material, characterized in that: Using MgAl-LDH as the substrate, the interlayer spacing of MgAl-LDH was enlarged by EDTA intercalation.

2. The EDTA-intercalated MgAl-LDH nanosheet material according to claim 1, characterized in that: The MgAl-LDH interlayer spacing can be expanded to above.

3. A method for preparing EDTA intercalated MgAl-LDH nanosheet material, characterized in that: The details are as follows: Dissolve Mg(NO3)2 and Al(NO3)3 in water to form a mixed solution; The pH value of the mixed solution is adjusted to 11 with a NaOH solution; the mixed solution after the pH adjustment is aged for 2 hours at 80° C. to form MgAl-LDH nanosheets; the pH value of the solution is then adjusted to 5.5 with EDTA, and an ion exchange reaction is performed to allow EDTA to be intercalated into the MgAl-LDH structure; after the reaction is completed, the reaction product is washed with water, and the EDTA-intercalated MgAl-LDH nanosheet material is obtained after drying.

4. The preparation method according to claim 3, characterized in that: In the mixed solution, the molar ratio of Mg(NO3)2 to Al(NO3)3 is 2:

1.

5. The preparation method according to claim 3, characterized in that: The ion exchange reaction time is 4-12 hours.

6. The preparation method according to claim 3, characterized in that: The drying temperature is 40-60° C., and the drying time is 12-24 hours.

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