A method of electron beam irradiation to prepare MXenes materials
By treating MAX phase materials with electron beam irradiation combined with strong acid solution, the problems of high environmental hazard and low etching yield in existing technologies have been solved, and efficient and controllable MXenes materials with dendritic layered structure have been prepared, which improves catalytic performance.
Patent Information
- Application Number
- CN202410120492.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-29
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2044-01-29
AI Technical Summary
In existing technologies, the preparation of MXenes materials requires etching with HF acid containing F ions, which poses significant environmental and human health hazards and results in low etching yield.
The MAX phase material was treated with electron beam irradiation combined with a strong acid solution. The electron beam irradiation transformed it into a layered structure. The use of HF acid containing F ions was avoided. Strong acid solutions such as perchloric acid, selenic acid, or chloric acid were used, and hydrogen peroxide was added as an irradiation aid. After acid etching and electron beam irradiation, the material was centrifuged and freeze-dried.
The preparation of MXenes materials is highly efficient and controllable, avoiding the use of toxic F ions, which is environmentally friendly. Furthermore, the prepared MXenes materials have a dendritic layered structure, which increases the number of active sites and improves the catalytic effect.
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Figure CN117963919B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of nanolayer materials, in particular to a method for preparing MXenes material by electron beam irradiation. BACKGROUND
[0002] Compared with graphene, new two-dimensional transition metal carbon (nitrogen) compounds (MXenes) not only inherit the excellent performance of traditional two-dimensional nanomaterials, but also show high conductive surface similar to graphene and metal, and have high energy density and good electromagnetic shielding performance. Generally, MXenes are obtained by selectively etching "A" layer atoms from precursor MAX phase by chemical etching. MAX phase is a three-dimensional layered ceramic material, and MXenes are a new type of carbon (nitrogen) compound two-dimensional nanolayer material. The chemical formula of MAX phase is M n+1 AX n (n = 1, 2 or 3), and the chemical formula of MXenes is M n+1 X n T x wherein M is a transition metal (such as Sc, V, Ti, Zr and Cr, etc.), X is carbon, nitrogen or carbon-nitrogen, and T is a surface group (such as O, OH or F, etc.). Research shows that the etching conditions mainly depend on the type of atomic bond and the strength of the material, and MXenes containing V-, Cr-, Zr-, Nb-, Ta- and Mo- have more stringent etching conditions than MXenes containing Ti-. The preparation methods that can be realized in the laboratory at present include HF acid, in-situ etching, molten salt, Lewis acid etching and electrochemical etching. Due to the problems of yield and efficiency, HF acid containing F ions or in-situ formed HF are mostly used to etch the precursor MAX phase, but F ions are harmful to the environment and human body (Chem. Mater. 2017, 29, 18, 7633-7644). If other methods are used for etching, incomplete etching will occur, and the yield is very low (J. Name., 2012, 00, 1-3). How to find a method that can not use F ion-containing solution and also has a large etching yield is one of the problems to be solved. SUMMARY
[0003] To solve the problems in the prior art, the main purpose of the present application is to provide a method for preparing MXenes material by electron beam irradiation.
[0004] To solve the above technical problems, according to one aspect of the present application, the present application provides the following technical scheme:
[0005] A method for preparing MXenes material by electron beam irradiation, comprising the following steps:
[0006] S1, mixing the MAX phase material powder with a strong acid solution to obtain a mixed solution, and performing electron beam irradiation on the mixed solution;
[0007] S2, washing the solution after the irradiation to neutral, then performing centrifugal treatment, taking the supernatant after multiple centrifugal treatments, and freeze-drying to obtain the MXenes material.
[0008] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S1, the solid-liquid ratio of the MAX phase powder and the strong acid solution is 1g:(10-12)mL.
[0009] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S1, the MAX phase material is one of Ti3AlC2, Ti2AlC, Nb2AlC, V2AlC, Cr2AlC and Ta4AlC3.
[0010] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S1, the strong acid solution is at least one of perchloric acid, selenic acid and chloric acid, and the concentration is 12-15mol / L.
[0011] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S1, the electron beam irradiation energy is 15MeV, and the electron beam irradiation dose is 10-20kGy.
[0012] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S1, 5-15% of the volume of the strong acid solution is added as an irradiation auxiliary agent in the form of a 1wt% hydrogen peroxide solution during the electron beam irradiation treatment.
[0013] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S1, the electron beam irradiation time is 6-12h.
[0014] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S2, the centrifugal treatment speed is 2500-3000rpm, and the centrifugal treatment time is 4-8min.
[0015] As a preferred scheme of the method for preparing the MXenes material by electron beam irradiation, in the step S2, the freeze-drying is performed in a vacuum environment, and the vacuum pressure is ≤10Pa.
[0016] As a preferred scheme of the method for preparing MXenes material by electron beam irradiation, in the step S2, the freeze-drying temperature is-90 to-100 DEG C, and the freeze-drying time is 24 to 48 h.
[0017] The beneficial effects of the present application are as follows:
[0018] The present application provides a method for preparing MXenes material by electron beam irradiation, which combines acid etching and electron beam irradiation treatment. The original tightly stacked structure is modified into a sheet structure by electron beam irradiation while etching the MAX phase. The MXenes material prepared by the method has high etching efficiency and controllability, avoids the introduction of toxic F ion acid, is environmentally friendly and easy to operate, and has a dendritic layered structure. The dendritic layered structure has more active sites than the normal accordion structure, and has better catalytic effect as a catalyst. BRIEF DESCRIPTION OF DRAWINGS
[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the drawings shown.
[0020] Figure 1 SEM image of the MXene material prepared in Example 1 of the present application.
[0021] Figure 2 XRD image of the MXene material prepared in Example 1 of the present application.
[0022] Figure 3 SEM image of the material prepared in Comparative Example 1 of the present application.
[0023] Figure 4 SEM image of the material prepared in Comparative Example 2 of the present application.
[0024] Figure 5 SEM image of the material prepared in Comparative Example 3 of the present application.
[0025] The implementation, functional characteristics and advantages of the present application will be further described with reference to the embodiments and the drawings. DETAILED DESCRIPTION
[0026] The technical solutions in the embodiments will be described clearly and completely below. Obviously, the described embodiments are only a part of, rather than all of, the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the protection scope of the present application.
[0027] The main purpose of the present application is to provide a method for preparing MXenes material by electron beam irradiation, which can modify the original close-packed structure to a sheet structure by electron beam irradiation while etching MAX phase in acid, and obtain MXenes material with dendritic layered structure, and the method is simple and convenient to operate and has high stability.
[0028] According to one aspect of the present application, the present application provides the following technical solutions:
[0029] A method for preparing MXenes material by electron beam irradiation, comprising the following steps:
[0030] S1, mixing MAX phase powder and strong acid solution to obtain a mixed solution, adding the mixed solution into a reaction kettle, and performing electron beam irradiation on the mixed solution;
[0031] S2, washing the solution after irradiation to neutral, and then performing centrifugal treatment, taking the supernatant after multiple centrifugations, and freeze-drying to obtain MXenes material.
[0032] Preferably, in the step S1, the solid-liquid ratio of the MAX phase powder and the strong acid solution is 1g:(10-12)mL. Specifically, the solid-liquid ratio of the MAX phase powder and the strong acid solution can be, for example, any one of 1g:10mL, 1g:10.5mL, 1g:11mL, 1g:11.5mL, 1g:12mL or a range between any two of them.
[0033] Preferably, in the step S1, the MAX phase material is one of Ti3AlC2, Ti2AlC, Nb2AlC, V2AlC, Cr2AlC and Ta4AlC3; and the strong acid solution is at least one of perchloric acid, selenic acid and chloric acid, and the concentration is 12-15mol / L. Specifically, the concentration of the strong acid solution can be, for example, any one of 12mol / L, 12.5mol / L, 13mol / L, 13.5mol / L, 14mol / L, 14.5mol / L, 15mol / L or a range between any two of them.
[0034] Preferably, in the step S1, the electron beam irradiation energy is 15 MeV, and the electron beam irradiation dose is 10-20 kGy. Specifically, the electron beam irradiation dose can be, for example, any one of 10 kGy, 12 kGy, 15 kGy, 18 kGy, 20 kGy, or a range between any two of them.
[0035] Preferably, in the step S1, a 1wt% hydrogen peroxide solution with a concentration of 5-15% of the volume of the strong acid solution is added as an irradiation auxiliary agent during the electron beam irradiation treatment. Specifically, the hydrogen peroxide solution can be, for example, any one of 15%, 18%, 20%, 22%, 25% of the volume of the strong acid solution, or a range between any two of them.
[0036] Preferably, in the step S1, the electron beam irradiation time is 6-12 h. Specifically, the electron beam irradiation time can be, for example, any one of 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, 12 h, or a range between any two of them.
[0037] Preferably, in the step S2, the centrifugal treatment can be performed multiple times as needed, and the speed of each centrifugal treatment is 2500-3000 rpm, and the time of each centrifugal treatment is 4-8 min. Specifically, the speed of the centrifugal treatment can be, for example, any one of 2500 rpm, 2600 rpm, 2700 rpm, 2800 rpm, 2900 rpm, 3000 rpm, or a range between any two of them; the time of the centrifugal treatment can be, for example, any one of 4 min, 5 min, 6 min, 7 min, 8 min, or a range between any two of them.
[0038] Preferably, in the step S2, liquid nitrogen is used for quick freezing before freeze-drying.
[0039] Preferably, in the step S2, the freeze-drying is performed in a vacuum environment, and the vacuum pressure is ≤10 Pa.
[0040] Preferably, in the step S2, the freeze-drying temperature is -90 to -100℃, and the freeze-drying time is 24-48 h. Specifically, the freeze-drying temperature can be, for example, any one of -90℃, -93℃, -95℃, -98℃, -100℃, or a range between any two of them; the freeze-drying time can be, for example, any one of 24 h, 30 h, 36 h, 42 h, 48 h, or a range between any two of them.
[0041] The technical solutions of the present application are further described below in combination with specific embodiments.
[0042] Example 1
[0043] A method for preparing MXenes material by electron beam irradiation, comprising the following steps:
[0044] S1, 10 g of MAX phase Ta4AlC3 powder is mixed with 100 mL of 12 mol / L hydrochloric acid solution to obtain a mixed solution, 10 mL of 1 wt% hydrogen peroxide solution is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15 MeV, the electron beam irradiation dose is adjusted to 10 kGy, and the mixed solution is subjected to electron beam irradiation for 10 h;
[0045] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are carried out, the rotation speed of centrifugal treatment is 3000 rpm, and the total time of multiple centrifugal treatments is 25 min; the supernatant after centrifugation is first rapidly frozen using liquid nitrogen, and then freeze-dried, under the pressure vacuum of 1 Pa, at -95℃ for 42 h, to obtain Ta4C3T x MXenes material.
[0046] The Ta4C3T x MXenes material prepared in this embodiment has a SEM image as shown in Figure 1 , and an XRD image as shown in Figure 2 . It can be seen from Figure 1 that the Ta4C3T x MXenes material presents a special dendritic layered structure; it can be seen from Figure 2 that the Ta4C3T x MXenes material Al peak is wide and weak, and the peak is sharp, which indicates that the material obtained by this method has high crystallinity.
[0047] Example 2
[0048] A method for preparing MXenes material by electron beam irradiation, comprising the following steps:
[0049] S1, 10 g of MAX phase Ta4AlC3 powder is mixed with 120 mL of 15 mol / L selenium acid solution to obtain a mixed solution, 10 mL of 1 wt% hydrogen peroxide solution is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15 MeV, the electron beam irradiation dose is adjusted to 20 kGy, and the mixed solution is subjected to electron beam irradiation for 6 h;
[0050] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are carried out, the rotation speed of centrifugal treatment is 2500 rpm, the total time of multiple centrifugal treatments is 20 min; the supernatant after multiple centrifugal treatments is first rapidly frozen using liquid nitrogen, and then freeze-dried, under 1 Pa pressure vacuum, at -90 DEG C, freeze-drying for 48 h, to obtain Ta4C3T x MXenes material.
[0051] Example 3
[0052] A method for preparing a MXenes material by electron beam irradiation, comprising the following steps:
[0053] S1, 10 g of Ta4AlC3 powder in MAX phase is mixed with 100 mL of chloric acid solution with a concentration of 12 mol / L to obtain a mixed solution, 10 mL of hydrogen peroxide solution with a concentration of 1 wt% is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15 MeV, the electron beam irradiation dose is adjusted to 15 kGy, and the mixed solution is subjected to electron beam irradiation for 12 h;
[0054] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are carried out, the rotation speed of centrifugal treatment is 3500 rpm, the total time of multiple centrifugal treatments is 24 min; the supernatant after multiple centrifugal treatments is first rapidly frozen using liquid nitrogen, and then freeze-dried, under 1 Pa pressure vacuum, at -100 DEG C, freeze-drying for 24 h, to obtain Ta4C3T x MXenes material.
[0055] Example 4
[0056] A method for preparing a MXenes material by electron beam irradiation, comprising the following steps:
[0057] S1, 10 g of Ti3AlC2 powder in MAX phase is mixed with 100 mL of high-chloric acid solution with a concentration of 12 mol / L to obtain a mixed solution, 10 mL of hydrogen peroxide solution with a concentration of 1 wt% is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15 MeV, the electron beam irradiation dose is adjusted to 10 kGy, and the mixed solution is subjected to electron beam irradiation for 10 h;
[0058] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are carried out, the rotation speed of centrifugal treatment is 3000 rpm, the total time of multiple centrifugal treatments is 18 min; the supernatant after multiple centrifugal treatments is first rapidly frozen using liquid nitrogen, and then freeze-dried, under 1 Pa pressure vacuum, at -95 DEG C, freeze-drying for 42 h, to obtain Ti3C2T xMXenes material.
[0059] Example 5
[0060] A method for preparing a MXenes material by electron beam irradiation, comprising the following steps:
[0061] S1, 10g of MAX phase Ti2AlC powder is mixed with 100mL of perchloric acid solution with a concentration of 12mol / L to obtain a mixed solution, 10mL of hydrogen peroxide solution with a concentration of 1wt% is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15MeV, the electron beam irradiation dose is adjusted to 10kGy, and the mixed solution is subjected to electron beam irradiation for 10h;
[0062] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are carried out, the rotation speed of the centrifugal treatment is 3000rpm, and the total time of the multiple centrifugal treatments is 20min; the supernatant after multiple centrifugations is first rapidly frozen using liquid nitrogen, and then freeze-dried, under a pressure vacuum of 1Pa and at-99℃ for 42h to obtain Ti2CT x MXenes material.
[0063] Example 6
[0064] A method for preparing a MXenes material by electron beam irradiation, comprising the following steps:
[0065] S1, 10g of MAX phase Nb2AlC powder is mixed with 100mL of perchloric acid solution with a concentration of 15mol / L to obtain a mixed solution, 10mL of hydrogen peroxide solution with a concentration of 1wt% is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15MeV, the electron beam irradiation dose is adjusted to 16kGy, and the mixed solution is subjected to electron beam irradiation for 12h;
[0066] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are carried out, the rotation speed of the centrifugal treatment is 3000rpm, and the total time of the multiple centrifugal treatments is 18min; the supernatant after multiple centrifugations is first rapidly frozen using liquid nitrogen, and then freeze-dried, under a pressure vacuum of 1Pa and at-95℃ for 42h to obtain Nb2CT x MXenes material.
[0067] Example 7
[0068] A method for preparing a MXenes material by electron beam irradiation, comprising the following steps:
[0069] S1, 10 g of MAX phase V2AlC powder is mixed with 100 mL of a perchloric acid solution with a concentration of 15 mol / L to obtain a mixed solution, 10 mL of a hydrogen peroxide solution with a concentration of 1 wt% is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15 MeV, the electron beam irradiation dose is adjusted to 15 kGy, and the mixed solution is subjected to electron beam irradiation for 12 h;
[0070] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are performed, the rotation speed of the centrifugal treatment is 3000 rpm, and the total time of the multiple centrifugal treatments is 15 min; the supernatant after the multiple centrifugal treatments is first rapidly frozen using liquid nitrogen, and then freeze-dried, under a pressure vacuum of 1 Pa and at -96℃ for 48 h to obtain V2CT x MXenes material.
[0071] Example 8
[0072] A method for preparing a MXenes material by electron beam irradiation, comprising the following steps:
[0073] S1, 10 g of MAX phase Cr2AlC powder is mixed with 100 mL of a perchloric acid solution with a concentration of 13 mol / L to obtain a mixed solution, 10 mL of a hydrogen peroxide solution with a concentration of 1 wt% is added to the mixed solution as an irradiation auxiliary agent, the electron beam irradiation energy is adjusted to 15 MeV, the electron beam irradiation dose is adjusted to 15 kGy, and the mixed solution is subjected to electron beam irradiation for 12 h;
[0074] S2, after the solution after irradiation is washed with deionized water until the pH test paper shows neutral, multiple centrifugal treatments are performed, the rotation speed of the centrifugal treatment is 3000 rpm, and the total time of the multiple centrifugal treatments is 22 min; the supernatant after the multiple centrifugal treatments is first rapidly frozen using liquid nitrogen, and then freeze-dried, under a pressure vacuum of 1 Pa and at -92℃ for 48 h to obtain Cr2CT x MXenes material.
[0075] Comparative Example 1
[0076] The difference from Example 1 is that the electron beam irradiation dose is 8 kGy and the electron beam irradiation time is 5 h.
[0077] The SEM image of the material prepared in this comparative example is shown in Figure 3 From Figure 3 it can be clearly observed that the material prepared in Comparative Example 1 has a layered morphology, but unlike the dendritic layered structure prepared in Example 1, only a small amount of dendritic morphology is present, and most of it is only a simple layered case.
[0078] Comparative Example 2
[0079] The difference from Example 1 is that no electron beam irradiation was performed; the sample was simply placed in an acid solution for 10 hours.
[0080] SEM images of the materials prepared in this comparative example are shown below. Figure 4 As shown, from Figure 4 It can be clearly observed that: Comparative Example 2 showed almost no etching reaction and remained a tightly stacked MAX phase.
[0081] Comparative Example 3
[0082] The difference from Example 1 is that electron beam irradiation was performed without the addition of hydrogen peroxide for 10 hours.
[0083] SEM images of the materials prepared in this comparative example are shown below. Figure 5 As shown, from Figure 5 It can be clearly observed that: Comparative Example 3 also showed almost no etching, and the powder sample obtained without electron beam irradiation (such as...) Figure 4 (As shown) there is no difference.
[0084] As can be seen from the above examples and comparative examples, the present invention combines acid etching and electron beam irradiation. While acid etching the MAX phase, electron beam irradiation is used to modify the originally tightly stacked structure into a layered structure. Due to insufficient irradiation dose and time, Comparative Example 1 only has a small amount of dendritic morphology, and most of them are still simple layered structures; Comparative Examples 2 and 3 were not irradiated or did not add irradiation aids, and there was almost no etching; while the MXenes material prepared by the method of the present invention has high etching efficiency and high controllability, avoids the introduction of toxic F ion acid, is environmentally friendly, simple to operate, and the obtained MXenes material has a dendritic layered structure.
[0085] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.
Claims
1. A method for preparing MXenes materials by electron beam irradiation, characterized in that, Includes the following steps: S1. A mixed solution is obtained by mixing MAX phase material powder with a strong acid solution, and the mixed solution is irradiated with an electron beam. The solid-liquid ratio of MAX phase powder to strong acid solution is 1g:(10-12)mL. The strong acid solution is at least one of perchloric acid, selenic acid, and chloric acid, with a concentration of 12-15mol / L. The electron beam irradiation energy is 15MeV, and the electron beam irradiation dose is 10-20kGy. During electron beam irradiation, 5-15% of the volume of the strong acid solution with a concentration of 1wt% hydrogen peroxide solution is added as an irradiation aid. The electron beam irradiation time is 6-12h. S2. After irradiation, the solution is washed with water until neutral, then centrifuged. The supernatant after multiple centrifugations is freeze-dried to obtain MXenes material.
2. The method for preparing MXenes materials by electron beam irradiation according to claim 1, characterized in that, In step S1, the MAX phase material is one of Ti3AlC2, Ti2AlC, Nb2AlC, V2AlC, Cr2AlC, and Ta4AlC3.
3. The method for preparing MXenes materials by electron beam irradiation according to claim 1, characterized in that, In step S2, the centrifugation speed is 2500-3000 rpm and the centrifugation time is 4-8 min.
4. The method for preparing MXenes materials by electron beam irradiation according to claim 1, characterized in that, In step S2, freeze drying is carried out under vacuum, with a vacuum pressure ≤10Pa.
5. The method for preparing MXenes materials by electron beam irradiation according to claim 1, characterized in that, In step S2, the freeze-drying temperature is -90~-100℃, and the freeze-drying time is 24~48h.
Citation Information
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