A Ti3C2T x Thin film enhanced toughened microwave annealing method

Abstract

The application belongs to the technical field of two-dimensional transition metal nanomaterial post-processing, and particularly discloses a Ti3C2T x The microwave annealing method for film strengthening and toughening comprises the following steps: Ti3AlC2 is treated by physical and chemical reaction to obtain a titanium carbide suspension, and then vacuum-assisted filtration drying is performed to obtain Ti3C2T x Film; the prepared Ti3C2T x Film sample is placed in a microwave reaction cavity; inert protective gas is introduced into the microwave reaction cavity, and the gas in the reaction cavity is discharged until the air in the cavity is completely discharged; the microwave loading power is adjusted to perform microwave annealing on the titanium carbide film, the total length of the loaded microwave power is controlled, and the power loading period and the power stopping period in each cycle are controlled to obtain Ti3C2T x Film with low defect density, compactness and high strength and toughness. The annealing device for microwave heating has the characteristics of rapid heating and high energy transmission, can greatly shorten the time required by the annealing process, improve the production efficiency, and can reduce the generation of temperature gradient and thermal stress.

Description

Technical Field

[0001] This invention belongs to the field of post-processing technology for two-dimensional transition metal nanomaterials, specifically relating to a method applicable to Ti3C2T. x Microwave annealing method for thin film reinforcement and toughening. Background Technology

[0002] Titanium carbide (Ti3C2T) x ) is a novel two-dimensional material whose chemical formula consists of titanium (Ti), carbon (C), and surface functional groups (T). x Composed of Ti3C2T x It has a graphene-like layered structure, in which titanium carbide layers and functionalized group layers are stacked alternately. Ti3C2T x Its excellent electrical conductivity makes it a promising candidate for applications in electronic devices, batteries, capacitors, and other fields. Ti3C2T x The functional groups on its surface endow it with high chemical activity, enabling it to react with other substances, such as through catalysis and adsorption. Ti3C2T x Due to its near-metallic high electrical conductivity, high thermal conductivity, low thermal expansion ratio, tunable surface, strong hydrophilicity, strong magnetism, and high electrochemical activity, it is highly favored in fields such as electrochemical energy storage, sensors, catalysis, biomedicine, and composite materials.

[0003] Compared to graphene, Ti3C2T x Ti3C2T has higher bending stiffness. x The monolayer exhibits a high Young's modulus (333±30 GPa), but due to titanium carbide (Ti3C2T) x Nanosheets tend to stack spontaneously, resulting in defects and stress concentrations that limit their deformation and energy dissipation. This uneven stress distribution, in turn, reduces the overall mechanical properties of the material.

[0004] To improve titanium carbide (Ti3C2T) x The problem of spontaneous stacking of nanosheets can be addressed by optimizing the preparation process (such as wet spinning), constructing composite materials (synergistic with different nanofillers), and heat treatment (isothermal annealing). For titanium carbide (Ti3C2T...) x Heat treatment can reduce surface defects, enhance toughness, and improve performance of Ti3C2T, making it an economical and efficient method. However, existing heat treatment methods suffer from drawbacks such as long processing time, high energy consumption, and difficulty in controlling oxidation levels. Therefore, it is essential to develop a new heat treatment method suitable for Ti3C2T. x Microwave annealing method for thin film reinforcement and toughening. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a method applicable to Ti3C2T. x A microwave annealing method for thin film reinforcement and toughening, utilizing Ti3C2T x The electromagnetic response properties of Ti3C2T can be rapidly obtained through microwave heat treatment to achieve strong and tough Ti3C2T. x For thin films, microwave annealing is more energy-efficient than traditional annealing methods.

[0006] To achieve the above objectives, one of the technical solutions of the present invention is: a method applicable to Ti3C2T x A microwave annealing method for thin film reinforcement and toughening includes the following steps:

[0007] (1) Titanium carbide aluminum (Ti3AlC2) was treated by physicochemical reaction to obtain a titanium carbide suspension, and then vacuum-assisted filtration and drying were performed to obtain Ti3C2T x film;

[0008] (2) The Ti3C2T obtained in step (1) x The thin film sample was placed inside the microwave reaction chamber;

[0009] (3) Inert protective gas is introduced into the microwave reaction cavity, and the gas in the reaction cavity is discharged at the same time until all the air in the cavity is discharged.

[0010] (4) Adjust the microwave loading power to perform microwave annealing on titanium carbide thin films, and control the total duration of microwave loading power and the power loading and stopping periods in each cycle to obtain Ti3C2T films with low defect density, dense and toughness. x film.

[0011] In a preferred embodiment of the present invention, the physicochemical reaction in step (1) specifically involves selective etching using a strong acid, intercalation using an intercalating agent, and stripping using physical actions such as ultrasound and centrifugation, ultimately obtaining a suspension of titanium carbide.

[0012] More preferably, the strong acid is a hydrofluoric acid solution or hydrofluoric acid obtained by in-situ reaction of concentrated hydrochloric acid with a fluorine-containing salt, and the intercalating agent includes at least one of water, ethanol, dimethyl sulfoxide, polymer molecules, and ionic salts containing alkali metals.

[0013] More preferably, the polymer molecule is polyvinyl alcohol.

[0014] In a preferred embodiment of the present invention, the vacuum-assisted filtration and drying in step (1) involves filtration and separation using a vacuum negative pressure and an aqueous filter membrane, and the Ti3C2T x The film is dried with the aid of temperature not exceeding 60°C.

[0015] In a preferred embodiment of the present invention, the inert protective gas in step (3) includes at least one of helium, argon, and nitrogen.

[0016] In a preferred embodiment of the present invention, the microwave loading power in step (4) is 400-1400W.

[0017] In a preferred embodiment of the present invention, the total time for microwave power loading in step (4) is ≤4s, the power loading period is ≤2s, and the power stopping period is 1-2s.

[0018] To achieve the above objectives, the second technical solution of the present invention is: a method applicable to Ti3C2T x Reinforced and toughened Ti3C2T prepared by microwave annealing method for thin film reinforcement and toughening x film.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The microwave heating annealing device of the present invention has the characteristics of rapid heating and efficient energy transfer, which can greatly shorten the time required for the annealing process, improve production efficiency, and at the same time reduce the generation of temperature gradient and thermal stress, which is conducive to maintaining the overall performance of the material.

[0021] 2. The present invention provides a method for using titanium carbide (Ti3C2T) x Microwave annealing for thin-film reinforcement and toughening can obtain titanium carbide (Ti3C2T) with low defect density and high orientation in a very short time. x Thin films; microwave flash heating helps promote the thin film development of Ti3C2T. x Nanosheets effectively densify the material without completely melting it, thus maintaining its high-entropy structure. Furthermore, microwave annealing is inexpensive, thereby reducing the cost of titanium carbide (Ti3C2T). x The annealing cost of the film is reduced, which is beneficial for large-scale mass production. Attached Figure Description

[0022] Figure 1 The Ti3C2T prepared in Example 1 x SEM images of the film cross-section before and after annealing, (a) before annealing, (b) after annealing. Detailed Implementation

[0023] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0024] A type that can be used in Ti3C2T xA microwave annealing method for thin film reinforcement and toughening includes the following steps:

[0025] (1) Titanium carbide aluminum (Ti3AlC2) was treated by physicochemical reaction to obtain a titanium carbide suspension, and then vacuum-assisted filtration and drying were performed to obtain Ti3C2T x film;

[0026] (2) The Ti3C2T obtained in step (1) x The thin film sample was placed inside the microwave reaction chamber;

[0027] (3) Inert protective gas is introduced into the microwave reaction cavity, and the gas in the reaction cavity is discharged at the same time until all the air in the cavity is discharged.

[0028] (4) Adjust the microwave loading power to perform microwave annealing on titanium carbide thin films, and control the total duration of microwave loading power and the power loading period and power stopping period in each cycle to obtain Ti3C2T with low defect density, dense and toughness. x film.

[0029] The physicochemical reaction in step (1) specifically involves selective etching using strong acid, intercalation using an intercalating agent, and stripping using physical actions such as ultrasound and centrifugation, ultimately obtaining a suspension of titanium carbide.

[0030] The strong acid includes at least one of concentrated hydrochloric acid and a fluorine-containing salt, and hydrofluoric acid. The intercalating agent includes at least one of water, ethanol, dimethyl sulfoxide, polymer molecules, and an ionic salt containing an alkali metal.

[0031] The polymer molecule is polyvinyl alcohol.

[0032] The vacuum-assisted filtration and drying in step (1) involves using vacuum negative pressure and an aqueous filter membrane for filtration and separation, and separating Ti3C2T x The film is dried with the aid of temperature not exceeding 60°C.

[0033] The inert protective gas in step (3) includes at least one of helium, argon, and nitrogen.

[0034] The microwave loading power in step (4) is 400-1400W.

[0035] In step (4), the total time for microwave power loading is ≤4s, the power loading period is ≤2s, and the power stopping period is 1-2s.

[0036] A type that can be used in Ti3C2T x Strong and tough Ti3C2T prepared by microwave annealing method for thin film reinforcement and toughening x film.

[0037] Example 1

[0038] A type that can be used in Ti3C2T x A microwave annealing method for thin film reinforcement and toughening includes the following steps: 2g of 400-mesh titanium aluminum carbide is selected. Hydrofluoric acid (HF) is synthesized in situ using 2g of lithium fluoride (LiF) and 40mL of concentrated hydrochloric acid (HCl, 9M). The mixture is stirred at 35℃ for 24h to selectively etch the aluminum (Al) layer. After etching, the precipitate in the solution is repeatedly washed with deionized water, and then centrifuged at 3500rpm for 10min until pH≥6. Using ethanol as an intercalating agent, the mixture is sonicated in an ice bath at 500W for 1h, followed by centrifugation at 10000rpm for 10min, resulting in a black precipitate at the bottom of the centrifuge tube. The precipitate is then carefully redispersed in deionized water, sonicated in an ice bath at 500W for 20min, and then centrifuged at 3500rpm for 10min to obtain the desired titanium carbide (Ti3C2T). x ) suspension; add 100 mL of Ti3C2T x The suspension was filtered using vacuum-assisted filtration to obtain the corresponding Ti3C2T. x The thin film sample was placed in a semi-circular crucible, and then placed inside a microwave reaction chamber. Argon gas was introduced into the reaction chamber while air was simultaneously purged until all air was expelled. The microwave loading power was adjusted to 800W, and after observing the generation of plasma spark discharge in the reactor for 2 seconds, the microwave was turned off. After waiting for 1 second, the sample was removed, yielding a strong and tough Ti3C2T. x film.

[0039] Regarding the above Ti3C2T x The cross-section of the thin film was observed by SEM scanning before and after annealing, and the results are shown in the attached figure. Figure 1 As shown, Ti3C2T after microwave annealing x Thin film cross-section, compared to unannealed Ti3C2T x The film is denser and more uniform.

[0040] Example 2

[0041] A type that can be used in Ti3C2T xA microwave annealing method for thin film reinforcement and toughening includes the following steps: 2g of 400-mesh titanium aluminum carbide is selected. Hydrofluoric acid (HF), synthesized in situ using 2g of lithium fluoride (LiF) and 40mL of concentrated hydrochloric acid (HCl, 9M), is stirred at 35℃ for 24h to selectively etch the aluminum (Al) layer. After etching, the precipitate in the solution is repeatedly washed with deionized water and centrifuged at 3500rpm for 10min until pH≥6. Using ethanol as an intercalating agent, the mixture is sonicated in an ice bath at 500W for 1h and then centrifuged at 10000rpm for 10min to obtain a black precipitate at the bottom of the centrifuge tube. The precipitate is then carefully redispersed in deionized water, sonicated in an ice bath at 500W for 20min, and then centrifuged at 3500rpm for 10min to obtain the desired titanium carbide (Ti3C2T). x ) suspension; add 100 mL of Ti3C2T x The suspension was filtered using vacuum-assisted filtration to obtain the corresponding Ti3C2T. x The thin film sample was placed in a semi-circular crucible, and then placed inside a microwave reaction chamber. Argon gas was introduced into the reaction chamber while air was simultaneously purged until all air was expelled. The microwave loading power was adjusted to 400W, and after observing the generation of plasma spark discharge in the reactor for 2 seconds, the microwave was turned off. After waiting for 1 second, the sample was removed, yielding a strong and tough Ti3C2T. x film.

[0042] Example 3

[0043] A type that can be used in Ti3C2T x A microwave annealing method for thin film reinforcement and toughening includes the following steps: 2g of 400-mesh titanium aluminum carbide is selected. Hydrofluoric acid (HF), synthesized in situ using 2g of lithium fluoride (LiF) and 40mL of concentrated hydrochloric acid (HCl, 9M), is stirred at 35℃ for 24h to selectively etch the aluminum (Al) layer. After etching, the precipitate in the solution is repeatedly washed with deionized water and centrifuged at 3500rpm for 10min until pH≥6. Using ethanol as an intercalating agent, the mixture is sonicated in an ice bath at 500W for 1h and then centrifuged at 10000rpm for 10min to obtain a black precipitate at the bottom of the centrifuge tube. The precipitate is then carefully redispersed in deionized water, sonicated in an ice bath at 500W for 20min, and then centrifuged at 3500rpm for 10min to obtain the desired titanium carbide (Ti3C2T). x ) suspension; add 100 mL of Ti3C2T x The suspension was filtered using vacuum-assisted filtration to obtain the corresponding Ti3C2T. xThe thin film sample was placed in a semi-circular crucible, and then placed inside a microwave reaction chamber. Argon gas was introduced into the reaction chamber while air was simultaneously purged until all air was expelled. The microwave loading power was adjusted to 1400W, and after observing the generation of plasma spark discharge in the reactor for 2 seconds, the microwave was turned off. After waiting for 1 second, the sample was removed, yielding a strong and tough Ti3C2T. x film.

[0044] Example 4

[0045] A type that can be used in Ti3C2T x A microwave annealing method for thin film reinforcement and toughening includes the following steps: 2g of 400-mesh titanium aluminum carbide is selected. Hydrofluoric acid (HF), synthesized in situ using 2g of lithium fluoride (LiF) and 40mL of concentrated hydrochloric acid (HCl, 9M), is stirred at 35℃ for 24h to selectively etch the aluminum (Al) layer. After etching, the precipitate in the solution is repeatedly washed with deionized water and centrifuged at 3500rpm for 10min until pH≥6. Using ethanol as an intercalating agent, the mixture is sonicated in an ice bath at 500W for 1h and then centrifuged at 10000rpm for 10min to obtain a black precipitate at the bottom of the centrifuge tube. The precipitate is then carefully redispersed in deionized water, sonicated in an ice bath at 500W for 20min, and then centrifuged at 3500rpm for 10min to obtain the desired titanium carbide (Ti3C2T). x ) suspension; add 100 mL of Ti3C2T x The suspension was filtered using vacuum-assisted filtration to obtain the corresponding Ti3C2T. x The thin film sample was placed in a semi-circular crucible, and then placed inside a microwave reaction chamber. Argon gas was introduced into the reaction chamber while air was simultaneously purged until all air was expelled. The microwave loading power was adjusted to 800W, and microwaves were applied. After observing the generation of plasma spark discharge in the reactor, the microwaves were turned off after 1 second. After waiting for 1 second, the sample was removed, yielding a strong and tough Ti3C2T. x film.

[0046] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for Ti3C2T x thin film reinforcement toughening microwave annealing method characterized by, The method comprises the following steps: (1) Ti3AlC2 is treated by physical and chemical reaction to obtain a titanium carbide suspension, and then vacuum-assisted filtration and drying are performed to obtain Ti3C2T x thin film; (2) Ti3C2T prepared in step (1) is added to the solution prepared in step (1) to obtain a mixture x The thin film sample is placed in the microwave reaction cavity; (3) introducing inert protective gas into the microwave reaction cavity, and discharging the gas in the reaction cavity until the air in the cavity is completely discharged; (4) Adjusting the microwave loading power to perform microwave annealing on the titanium carbide film, controlling the total length of the loaded microwave power and the power loading period and power stopping period in each cycle, so as to obtain the Ti3C2T x film with low defect density, density, and strength The physical and chemical reaction in the step (1) is specifically selective etching by using strong acid, intercalation by using intercalation agent, and peeling by using ultrasonic and centrifugal force, and finally obtaining a suspension of titanium carbide, and the intercalation agent is ethanol; the microwave loading power in the step (4) is 400-1400W, the total time of the microwave loading power is ≤4s, the power loading period is ≤2s, and the power stop period is 1-2s.

2. The method for Ti3C2T x Thin film enhanced toughening microwave annealing method characterized in that, The strong acid is hydrofluoric acid solution or hydrofluoric acid obtained by in-situ reaction of concentrated hydrochloric acid and fluorine-containing salt.

3. The method for Ti3C2T x Thin film enhanced toughening microwave annealing method characterized in that, The vacuum-assisted filtration drying in the step (1) is to separate and filter by using vacuum negative pressure and water-based filter membrane, and to remove water in Ti3C2T x The film is assisted to dry at a temperature not exceeding 60 ℃.

4. The method for Ti3C2T x Thin film enhanced toughening microwave annealing method characterized in that, The inert protective gas in the step (3) comprises at least one of helium, argon and nitrogen.

5. A method for Ti3C2T x MXene film reinforcement toughening as claimed in any one of claims 1-4. x Toughened Ti3C2T x MXene film prepared by a microwave annealing method for film reinforcement toughening. x film.

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