Method for preparing MXene by etching based on alloying principle
By using the principle of alloying to etch and prepare MXene, the problem of highly toxic etching agents limiting the application of MXene has been solved, and environmentally friendly and low-cost MXene preparation has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SICHUAN UNIV
- Filing Date
- 2026-02-03
- Publication Date
- 2026-05-19
AI Technical Summary
The etching agents used in existing MXene preparation methods, such as hydrofluoric acid, are highly toxic, limiting their widespread application.
MXene is prepared by etching using the principle of alloying. This involves mixing the MAX phase, elemental metal, and modifier, heating and alloying them, then separating and drying the mixture to obtain MXene, thus avoiding the use of highly toxic etching agents.
A green and environmentally friendly MXene preparation process was achieved, reducing etching costs, and the MX layered structure was stabilized by combining metallic and non-metallic elements.
Smart Images
Figure CN122059409A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of materials preparation technology, and specifically to a method for preparing MXene by etching based on the principle of alloying. Background Technology
[0002] MXenes are a class of two-dimensional carbide / nitride compounds obtained by selectively etching A-site elements in the MAX phase. A typically refers to main group elements such as Al, Si, and Zn. The general chemical formula for MXenes is M. n+1 X n T x M represents early transition metals such as titanium (Ti), vanadium (V), chromium (Cr), and niobium (Nb), X represents carbon or nitrogen, and T represents... x This indicates a surface functional group.
[0003] Currently, the main methods for preparing MXene include etching with fluorine-containing solutions (HF / LiF+HCl), Lewis acid etching (CuCl2, NiBr2), electrochemical etching, and oxidation etching with non-metallic elements. However, the raw materials used in these methods are often highly acidic, especially hydrofluoric acid, which is highly toxic, greatly limiting its widespread application. Summary of the Invention
[0004] This invention addresses the problems existing in the prior art by providing a method for preparing MXene by etching based on the principle of alloying.
[0005] The technical solution adopted in this invention is: a method for preparing MXene by etching based on the principle of alloying, comprising the following steps: The MAX phase, elemental metal, and modifier are thoroughly mixed and ground. The desired MXene can be obtained by heating and alloying reaction, followed by separation and drying after the reaction is complete. The molar ratio of the MAX phase, elemental metal, and modifier is 1:0.5~3:0.5~3; the elemental metal is a metal that can be alloyed with the A phase; and the modifier is a non-metallic element that provides surface functional groups for MXene.
[0006] Furthermore, the MAX phase is one of the following substances: Ti2AlC, Ti2AlN, V2AlC, Nb2AlC, Ta2AlC, Ti2SnC, Ti2GaC, Ti2InC, Ti3AlC2, Ti3SiC2, Ti3GeC2, Ta3AlC2, Nb3AlC2, V3AlC2, Ti3SnC2, Ti4AlN3, Ta4AlC3, Nb4AlC3, and V4AlC3.
[0007] Furthermore, the elemental metal is one or more of Fe, Co, Ni, Cu, Si, Mn, Cr, Zr, Ti, Sn, Zn, and Mg, mixed in any proportion.
[0008] Furthermore, the modifier is one or more of F2, Cl2, Br2, I2, S, Se, Te, O2, and N2 mixed in any proportion.
[0009] Furthermore, the reaction temperature is 500–900 °C, and the reaction time is 1–8 h.
[0010] Furthermore, the heating rate during the heating process is 10 °C / min.
[0011] Furthermore, the separation process employs a magnet to separate magnetic byproducts.
[0012] Furthermore, the drying process employs vacuum drying, which is carried out at 60 ℃ for 6–12 h.
[0013] A method for preparing MXene by etching based on the principle of alloying, wherein the MXene has a multilayer structure.
[0014] The beneficial effects of this invention are: This invention discloses a method for obtaining MXene by etching MAX through alloying. This method does not require an oxidizing agent. A metallic element and an A-site element are alloyed to knock out the A-site element from the MAX phase. Simultaneously, a non-metallic element is added to bond with the MX layer, forming surface functional groups and stabilizing the MX layered structure to obtain the MXene material. The combined use of metallic and non-metallic elements completes the etching of MAX, eliminating the need for highly toxic HF or acidic etchants, thus reducing etching costs. The preparation process is green and environmentally friendly. Attached Figure Description
[0015] Figure 1 The image shows the XRD pattern of the MXene material obtained in Example 1 of this invention.
[0016] Figure 2 This is a SEM image of the MXene material obtained in Example 1 of the present invention.
[0017] Figure 3 The image shows the XRD pattern of the MXene material obtained in Example 2 of this invention.
[0018] Figure 4 This is a SEM image of the MXene material obtained in Example 2 of the present invention. Detailed Implementation
[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0020] A method for preparing MXene by etching based on the principle of alloying includes the following steps: The MAX phase, elemental metal, and modifier are thoroughly mixed and ground. The MAX phase is one of the following substances: Ti2AlC, Ti2AlN, V2AlC, Nb2AlC, Ta2AlC, Ti2SnC, Ti2GaC, Ti2InC, Ti3AlC2, Ti3SiC2, Ti3GeC2, Ta3AlC2, Nb3AlC2, V3AlC2, Ti3SnC2, Ti4AlN3, Ta4AlC3, Nb4AlC3, or V4AlC3.
[0021] The elemental metal is obtained by mixing one or more of Fe, Co, Ni, Cu, Si, Mn, Cr, Zr, Ti, Sn, Zn, and Mg in any proportion.
[0022] The modifier is one or more of F2, Cl2, Br2, I2, S, Se, Te, O2, and N2 mixed in any proportion; other compounds that can provide surface functional groups for MXene can also be used.
[0023] Etching is performed by heating and alloying. After sufficient reaction, the MXene is separated and dried to obtain the desired MXene. The etching temperature is 500–900 °C, and the etching time is 1–8 h. The heating rate during the heating process is 10 °C / min.
[0024] The molar ratio of the MAX phase, elemental metal, and modifier is 1:0.5~3:0.5~3; the elemental metal is a metal that can be alloyed with the A phase; and the modifier is a non-metallic element that provides surface functional groups for MXene.
[0025] The following embodiments are provided to illustrate the effects of the present invention. Example 1 A method for preparing MXene by etching based on the principle of alloying includes the following steps: Step 1: Weigh 0.5 g of Ti3AlC2, 0.656 g of Te and 0.143 g of Fe respectively, and grind and mix the raw materials evenly in an agate mortar.
[0026] Step 2: Pour the mixed material from Step 1 into a crucible, place the crucible in an argon atmosphere tube furnace, heat it to 750 ℃ at a rate of 10 ℃ per minute, hold it at that temperature for 60 minutes, and then cool it with the furnace.
[0027] Step 3: Disperse the product obtained in Step 2 into deionized water, remove byproducts by magnetic separation, and dry under vacuum at 60°C for 12 hours to obtain the desired MXene powder.
[0028] Figure 1 The image shows the XRD pattern of MXene obtained in this embodiment. It can be seen from the image that the diffraction peak of the MAX phase disappeared after the reaction, indicating that the MAX phase was effectively etched.
[0029] Figure 2 The image shows the SEM image of MXene obtained in this embodiment. As can be seen from the image, the obtained MXene has an accordion-like multilayer morphology, indicating that MXene was obtained.
[0030] Example 2 A method for preparing MXene by etching based on the principle of alloying includes the following steps: Step 1: Weigh 0.5 g of Ti2AlC, 0.947 g of Te and 0.207 g of Fe respectively, and grind and mix the raw materials evenly in an agate mortar.
[0031] Step 2: Pour the mixed material from Step 1 into a crucible, place the crucible in an argon atmosphere tube furnace, heat it to 750 ℃ at a rate of 10 ℃ per minute, hold it at that temperature for 60 minutes, and then cool it with the furnace.
[0032] Step 3: Disperse the product obtained in Step 2 into deionized water, remove byproducts by magnetic separation, and dry under vacuum at 60°C for 12 hours to obtain the desired MXene powder.
[0033] Figure 3 The image shows the XRD pattern of MXene obtained in this embodiment. It can be seen from the image that the diffraction peak of the MAX phase disappeared after the reaction, indicating that the MAX phase was effectively etched.
[0034] Figure 4 The image shows the SEM image of MXene obtained in this embodiment. As can be seen from the image, the obtained MXene has an accordion-like multilayer morphology, indicating that MXene was obtained.
[0035] This invention uses alloying etching to replace the original fluorine-containing solution or Lewis acid etching method. The etching process does not involve oxidant etching. It uses a metallic element to perform an alloying reaction with the A-site element in MAX to knock out the MAX phase. At the same time, non-metallic elements are added to form surface functional groups with the MX layer to stabilize the MX layered structure, thereby obtaining MXene with a layered structure.
Claims
1. A method for preparing MXene by etching based on the principle of alloying, characterized in that, Includes the following steps: The MAX phase, elemental metal, and modifier are thoroughly mixed and ground. The desired MXene is obtained by heating to carry out an alloying reaction, followed by separation and drying after the reaction is complete. The molar ratio of the MAX phase, elemental metal, and modifier is 1:0.5~3:0.5~3; the elemental metal is a metal that can be alloyed with the A phase; and the modifier is a non-metallic element that provides surface functional groups for MXene.
2. The method for preparing MXene based on an alloying strategy according to claim 1, characterized in that, The MAX phase is one of the following substances: Ti2AlC, Ti2AlN, V2AlC, Nb2AlC, Ta2AlC, Ti2SnC, Ti2GaC, Ti2InC, Ti3AlC2, Ti3SiC2, Ti3GeC2, Ta3AlC2, Nb3AlC2, V3AlC2, Ti3SnC2, Ti4AlN3, Ta4AlC3, Nb4AlC3, and V4AlC3.
3. The method for preparing MXene by etching based on the alloying principle according to claim 2, characterized in that, The elemental metal is one or more of Fe, Co, Ni, Cu, Si, Mn, Cr, Zr, Ti, V, Sn, Zn, Mg, and Ga, mixed in any proportion.
4. The method for preparing MXene by etching based on the alloying principle according to claim 2, characterized in that, The modifier is one or more of F2, Cl2, Br2, I2, S, Se, Te, O2, N2, B, and P, mixed in any proportion.
5. The method for preparing MXene by etching based on the alloying principle according to claim 1, characterized in that, The etching temperature is 500–900 °C, and the holding time is 1–8 h.
6. The method for preparing MXene by etching based on the alloying principle according to claim 5, characterized in that, The heating rate during the heating process is 10 °C / min.
7. The method for preparing MXene by etching based on the alloying principle according to claim 1, characterized in that, The separation process uses a magnet to separate magnetic byproducts.
8. The method for preparing MXene by etching based on the alloying principle according to claim 1, characterized in that, The drying process employs vacuum drying, which is carried out at 60 ℃ for 6–12 h.
9. The MXene obtained by any one of the preparation methods according to claims 1 to 8, characterized in that, The MXene has a multi-layered structure.