Method for manufacturing laminated members, method for manufacturing composite members, method for manufacturing sheet-like members, laminated members, composite members and sheet-like members

Abstract

The present invention provides a method for manufacturing laminated members that can synthesize laminated members such as MAX phase in a relatively short time, a method for manufacturing composite members including the laminated members, and a method for manufacturing sheet-like members such as MXene that can be manufactured relatively easily, quickly, and safely, as well as laminated members, composite members, and sheet-like members that can be manufactured by these manufacturing methods, respectively. [Solution] A precursor material 11 is prepared, consisting of alternating layers of a first layer 21 and a second layer 22 made of different components from the first layer 21. A molten metal 12 is prepared, consisting of components that are miscible with the components of the second layer 22 but poorly miscible or improper with the components of the first layer 21. Next, the precursor material 11 is immersed in the molten metal 12, causing all or part of the components of the second layer 22 to dissolve into the molten metal 12, forming a laminated member in which the components of the molten metal 12 have replaced the precursor material 11.

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a laminated member, a method for manufacturing a composite member, a method for manufacturing a sheet-like member, a laminated member, a composite member, and a sheet-like member. [Background technology]

[0002] Laminated materials, which consist of multiple layers stacked alternately, are expected to be used in various fields because they can be made up of various physical and chemical properties depending on the components of each layer. One example of such a laminated material is the MAX phase. The MAX phase is a material that has a fine layered structure and consists of pre-periodic transition metals (M components), A group elements (A components), and X elements (X components). The M components are, for example, one or more elements from Sc, Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; the A components are, for example, one or more elements from Al, Si, P, S, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Cd, In, Sn, Ir, Au, Tl, and Pb; and the X components are one or more elements from B, C, and N.

[0003] The MAX phase consists of alternating layers of M and X components and layers of A component, and more than 300 types have been discovered to date (see, for example, Non-Patent Document 1). Furthermore, the types of M, A, and X elements in the MAX phase continue to increase as new MAX phases are discovered or synthesized.

[0004] Conventionally, methods for synthesizing MAX phases have included direct solid-phase reactions such as pressureless sintering, hot-pressing, spark plasma sintering, and self-propagating high-temperature synthesis. However, these methods have limitations in the types of MAX phases that can be synthesized. Therefore, methods have been developed to synthesize new MAX phases by using already synthesized MAX phases and replacing component A with other elements using the molten salt method, or by replacing component A with a noble metal (see, for example, Non-Patent Document 1 and Patent Document 1).

[0005] The MAX phase is expected to have applications in various fields, but in recent years, it has attracted considerable attention as a precursor material for MXene, as a sheet-like material called MXene can be extracted by removing only component A. This MXene is a two-dimensional layered material that is expected to have applications in fields such as energy storage, lithium-ion batteries (LIBs), composite material reinforcements, sensors, porous materials, and biomaterials. Conventional methods for extracting only component A from the MAX phase when manufacturing MXene include wet etching using fluoride ions such as HF (see, for example, Patent Document 2 and Non-Patent Document 2) and etching using molten salt (see, for example, Patent Document 3 and Non-Patent Document 2).

[0006] Furthermore, the inventors have developed a so-called molten metal decomposition method as a method for producing porous metal materials having nanometer-sized micropores. This molten metal decomposition method involves immersing a metal material, which is a compound, alloy, or non-equilibrium alloy containing a second and a third component, each having positive and negative mixing heats relative to a first component, and having a melting point higher than the solidification point of a metal bath consisting of the first component, in a metal bath controlled to a temperature lower than the minimum liquidus temperature within the compositional variation range where the third component is reduced from the metal material until it reaches the second component. This selectively dissolves the third component into the metal bath, thereby obtaining a metal member with micropores (see, for example, Patent Document 4). [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Martin Dahlqvist, Michel W. Barsoum, Johanna Rosen, “MAX phases - Past, present, and future”, Materials Today, January / February 2024, Volume 72, pages 1-24, [online], URL: https: / / doi.org / 10.1016 / j.mattod.2023.11.010 [Non-Patent Document 2] Armin VahidMohammadi, Johanna Rosen, Yury Gogotsi, “The world of two-dimensional carbides and nitrides (MXenes)”, Science 372, 2021, [online], URL: https: / / doi.org / 10.1126 / science.abf1581 [Patent Documents]

[0008] [Patent Document 1] Special Publication No. 2021-515847 [Patent Document 2] U.S. Patent Application Publication No. 2020 / 0399771 [Patent Document 3] International Publication No. 2020 / 114196 [Patent Document 4] International Publication No. 2011 / 092909 [Overview of the project] [Problems that the invention aims to solve]

[0009] The methods for synthesizing the MAX phase of a new laminated material, as described in Non-Patent Document 1 and Patent Document 1, had the problem that the time required for component A to be replaced by other elements such as precious metals was long, taking at least several hours.

[0010] Methods for producing sheet-like MXene by wet etching using fluoride ions, as described in Patent Document 2 and Non-Patent Document 2, have the drawbacks of being dangerous due to the high toxicity of the F functional group and the time required to remove component A. Furthermore, methods for producing sheet-like MXene by etching using molten salt, as described in Patent Document 3 and Non-Patent Document 2, have the drawbacks of requiring high temperature and pressure, resulting in a complex manufacturing process, and also the time required to remove component A.

[0011] The present invention has been made in view of these problems, and aims to provide a method for manufacturing a laminated member that can synthesize a laminated member such as a MAX phase in a relatively short time, a method for manufacturing a composite member including the laminated member, a method for manufacturing a sheet-like member such as MXene that can be manufactured relatively easily, in a short time, and safely, and a laminated member, a composite member, and a sheet-like member that can be manufactured by these manufacturing methods, respectively. [Means for solving the problem]

[0012] To achieve the above objective, the method for manufacturing a laminated member according to the present invention is characterized by comprising: a step of preparing a precursor material comprising a first layer and a second layer made of different components from the first layer, which are alternately laminated; a step of preparing a molten metal comprising components that are miscible with respect to the components of the second layer, and components that are less miscible or improper than the components that constitute the second layer; and an immersion step of immersing the precursor material in the molten metal so that all or part of the components constituting the second layer dissolve into the molten metal and a laminated member is formed by replacing them with components of the molten metal.

[0013] The present invention provides a method for manufacturing a laminated member in which a precursor material, consisting of alternating layers of a first layer and a second layer, is immersed in molten metal to form a new laminated member in which all or part of the components constituting the second layer are replaced by components of the molten metal. In this case, for example, if a powdered precursor material is used, a new laminated member can be formed in a few hours to within one hour, which is faster than conventional methods such as the molten salt method or the method of synthesizing a new MAX phase from an existing MAX phase using precious metals. Furthermore, because it can be synthesized in a short time, bulk material can also be used as the precursor material by extending the immersion time in the molten metal.

[0014] Furthermore, in the method for manufacturing a laminated member according to the present invention, the components of the molten metal are miscible with respect to the components constituting the second layer, but are poorly miscible or improper with respect to the components constituting the first layer compared to the components constituting the second layer. Therefore, if the components are poorly miscible, the components constituting the second layer can be preferentially dissolved into the molten metal, and if the components are improper, only the components constituting the second layer can be dissolved into the molten metal. In this case, the first layer and the second layer are weakly bonded by van der Waals forces, and no strong chemical bonds are at work. Therefore, even if the second layer is dissolved, unlike the molten metal decomposition method described in Patent Document 4, the remaining components of the first layer do not self-organize into a different form and change. Therefore, according to the method for manufacturing a laminated member according to the present invention, a co-continuous composite material consisting of the components of the first layer and the components of the molten metal is not formed, and a new laminated member consisting of the components of the first layer, the components of the second layer and the components of the molten metal, or a new laminated member consisting of the components of the first layer and the components of the molten metal, can be formed.

[0015] The method for manufacturing a laminated member according to the present invention includes a recovery step for recovering the laminated member formed in the immersion step, thereby making it easy to obtain a new laminated member. As for the recovery step, for example, the laminated member may be recovered by removing it from the molten metal and cooling it after all or part of the components constituting the second layer have been replaced with components of the molten metal, or by cooling and solidifying the entire molten metal and then removing the surrounding solidified molten metal portion. In the method for manufacturing a laminated member according to the present invention, the components constituting the first layer and the components constituting the second layer only need to have different elemental compositions, although they may contain some of the same elements. Furthermore, the step of preparing the precursor material and the step of preparing the molten metal may be performed in any order, or they may be performed simultaneously.

[0016] The method for manufacturing a composite member according to the present invention is characterized in that, after the immersion step in the method for manufacturing a laminated member according to the present invention, the molten metal is solidified and recovered while the formed laminated member is immersed, thereby obtaining a composite member containing the laminated member and the components of the molten metal.

[0017] The manufacturing method of the composite member according to the present invention can easily obtain a composite member composed of a laminated member formed by the manufacturing method of the laminated member according to the present invention and the components of molten metal. The obtained composite member can be used in any way. Further, among the obtained composite members, only the laminated member may be recovered by removing the components of the molten metal around the laminated member.

[0018] The manufacturing method of the sheet-like member according to the present invention is characterized by having a removing step of recovering the laminated member formed by the manufacturing method of the laminated member according to the present invention and obtaining a sheet-like member by removing the components constituting the second layer and the components of the molten metal, or the components of the molten metal from the recovered laminated member.

[0019] The manufacturing method of the sheet-like member according to the present invention can obtain a sheet-like member composed of the components constituting the first layer. Further, for example, when manufacturing a laminated member, by selecting and using a component that elutes in an acid or an aqueous alkali solution in advance as the component of the molten metal, the components of the molten metal can be removed using the acid or the aqueous alkali solution, and a sheet-like member can be easily obtained. Thereby, compared with the case of etching using fluorine or molten salt, a sheet-like member can be manufactured easily, in a short time, and safely. It is preferable that the acid or the aqueous alkali solution is not harmful even if it remains in the sheet-like member.

[0020] In the method for manufacturing a laminated member according to the present invention, the immersion step may be modified by adjusting the time for immersing the precursor material in the molten metal and / or the temperature of the molten metal, so that a portion of the components constituting the first layer also dissolves into the molten metal, thereby forming a laminated member in which the precursor material is replaced by the components of the molten metal. In this case, by using a molten metal that is poorly miscible with respect to the components constituting the first layer, a portion of the components constituting the first layer can also be dissolved into the molten metal. The method for manufacturing a sheet-like member according to the present invention may include a removal step of recovering the laminated member thus formed and removing the components constituting the second layer and the components of the molten metal, or the components of the molten metal, from the recovered laminated member to obtain a porous sheet-like member. In this case, a new laminated member can be formed in which the components of the molten metal also penetrate the first layer. Furthermore, a porous sheet-like member can be easily obtained by removing the components of the molten metal from the laminated member.

[0021] The method for manufacturing a laminated member according to the present invention allows for the production of a MAX phase different from the precursor material as a laminated member, for example, by using an existing MAX phase as a precursor material. That is, in the method for manufacturing a laminated member according to the present invention, the precursor material is a MAX phase material, the first layer has an M component and an X component, the second layer has an A component, the M component consists of one or more elements from Sc, Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, the A component consists of one or more elements from Al, Si, P, S, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Cd, In, Sn, Ir, Au, Tl, and Pb, and the X component may consist of one or more elements from B, C, and N. Furthermore, the method for manufacturing a sheet-like member according to the present invention may include a removal step of recovering the laminated member made of the MAX phase thus formed, and removing the components constituting the second layer and the components of the molten metal, or the components of the molten metal, from the recovered laminated member to obtain a sheet-like member made of MXene material. This makes it possible to easily obtain a new MXene material as a sheet-like member that could not be manufactured from the existing MAX phase. Alternatively, a composite member containing the MAX phase and components of the molten metal can be obtained by immersing the formed laminated member made of the MAX phase in molten metal, solidifying the molten metal, and recovering it.

[0022] When the precursor material consists of the MAX phase, the molten metal is preferably composed of Ag, Au, Cu, or Mg. This allows for the formation of a MAX phase material as a laminated member, in which layered alloy portions consisting of components M and X are alternately laminated with layered portions consisting of component A and Ag, Au, Cu, or Mg, or Ag, Au, Cu, or Mg. Alternatively, a MAX phase material can be formed in which layered metal portions in which component A2 (composed of Ag, Au, Cu, or Mg) is dispersed in an alloy consisting of components M and X are alternately laminated with layered portions consisting of component A and component A2, or component A2. Furthermore, by removing component A and the component of the molten metal (component A2), or the component of the molten metal, a sheet-like member can be obtained, which is an MXene material containing components M and X, or a porous MXene material containing components M and X. Furthermore, by immersing the laminated member made of the formed MAX phase in molten metal, and then solidifying and recovering the molten metal, a composite member according to the present invention can be obtained in which the laminated member made of the MAX phase is covered by a coating layer made of component A2.

[0023] Furthermore, when this precursor material consists of the MAX phase, it is particularly preferable that the M component consists of Ti, the A component consists of Al or Si, the X component consists of C, and the molten metal consists of Ag or Cu.

[0024] Furthermore, when the precursor material consists of the MAX phase, it is preferable that the heat of mixing between component M and component X is negatively greater than the heat of mixing between component M and the components of the molten metal. In this case, alloying component M and component X is more thermodynamically stable than alloying component M with the components of the molten metal, so component A of the second layer is more readily dissolved into the molten metal than the components of the first layer having components M and X. [Effects of the Invention]

[0025] According to the present invention, it is possible to provide a method for manufacturing a laminated member that can synthesize a laminated member such as a MAX phase in a relatively short time, a method for manufacturing a composite member including the laminated member, a method for manufacturing a sheet-like member such as MXene that can be manufactured relatively easily, in a short time, and safely, and a laminated member, a composite member, and a sheet-like member that can be manufactured by these manufacturing methods, respectively. [Brief explanation of the drawing]

[0026] [Figure 1] (a) A cross-sectional view showing the precursor material and (b) A perspective view showing the immersion process of a method for manufacturing a laminated member according to an embodiment of the present invention. [Figure 2] The first embodiment of the method for manufacturing a laminated member according to an embodiment of the present invention is shown, (a) an SEM (scanning electron microscope) image of Ti3SiC2 in the MAX phase, which is the precursor material, (b) an SEM image of the laminated member obtained by the immersion process, (c) an SEM image of the obtained laminated member at a different position from (b), and (d) the X-ray diffraction spectrum of the obtained laminated member. [Figure 3] Figure 2 shows (a) an SEM image of the laminated member obtained by the immersion process in the first embodiment, (b) an SEM image of a magnified portion of (a), (c) a STEM (scanning transmission electron microscope) image of a magnified portion of (b), (d) a STEM image of a magnified portion of (c), and (e) a STEM image of a magnified portion of (d). [Figure 4] Figure 2 shows (a) a STEM image of the laminated member obtained by the immersion process in the first embodiment, and (b) a graph showing the elemental analysis results by EDX (energy-dispersive X-ray spectroscopy) along the line in (a). [Figure 5] The following are examples of the manufacturing method for a sheet-like member according to an embodiment of the present invention: (a) an SEM image of a sheet-like member obtained by the removal process from the laminated member of the first embodiment shown in Figure 2; (b) an enlarged SEM image of a part of (a); and (c) an enlarged SEM image of a part of (a) that is different from (b). [Figure 6]Figure 5 shows (a) a TEM (transmission electron microscope) image of the sheet-like member obtained by the removal process, (b) a TEM image of the obtained sheet-like member at a different position than (a), and (c) the electron diffraction pattern at the center of the circle in (b). [Figure 7] The second embodiment of the method for manufacturing a laminated member according to an embodiment of the present invention is shown, (a) an SEM image of Ti3AlC2, which is the precursor material MAX phase, and (b) an SEM image of the laminated member obtained by the immersion process. [Figure 8] Figure 7 shows (a) an SEM image of the laminated member obtained by the immersion process in the second embodiment, and (b) an elemental map of Al, (c) Ag, (d) C, and (e) Ti, showing the results of elemental analysis by EDX in the range shown in (a). [Figure 9] Figure 7 shows the second embodiment, (a) a STEM image of the laminated member obtained by immersion processes with different metal molten temperatures, (b) a magnified STEM image of the rectangular area in (a), (c) a magnified STEM image of a part of (b), (d) a magnified STEM image of a part of (c), (e) a magnified STEM image of the rectangular area in (d), and (f) a magnified STEM image of a part of (e). [Modes for carrying out the invention]

[0027] Embodiments of the present invention will be described below with reference to the drawings. Figures 1 to 9 show a method for manufacturing a laminated member, a method for manufacturing a sheet-like member, a laminated member, and a sheet-like member according to an embodiment of the present invention.

[0028] The method for manufacturing a laminated member according to an embodiment of the present invention first involves preparing a precursor material 11, as shown in Figure 1(a), in which a first layer 21 and a second layer 22, made of different components from the first layer 21, are alternately laminated. Furthermore, a molten metal 12 is prepared, which is miscible with the components constituting the second layer 22, and is less miscible or improper with the components constituting the first layer 21 than with the components constituting the second layer 22. At this time, the components constituting the first layer 21 and the components constituting the second layer 22 only need to have different elemental compositions, although they may contain some of the same elements. In addition, the steps of preparing the precursor material 11 and preparing the molten metal 12 may be performed in any order, or they may be performed simultaneously.

[0029] In a specific example shown in Figure 1(a), the precursor material 11 consists of an existing MAX phase. The MAX phase has a first layer 21 comprising components M and X, and a second layer 22 comprising component A. Here, component M consists of one or more elements from Sc, Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Component A consists of one or more elements from Al, Si, P, S, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Cd, In, Sn, Ir, Au, Tl, and Pb. Component X consists of one or more elements from B, C, and N.

[0030] Furthermore, the molten metal 12 may be any component that is miscible with the components constituting the second layer 22, and is less miscible or improper with the components constituting the first layer 21 than the components constituting the second layer 22. Considering the removal process when manufacturing the sheet member, it is preferable that the molten metal 12 consists of components that dissolve in an acid or alkaline aqueous solution. In a specific example, if the precursor material 11 consists of the MAX phase, the molten metal 12 consists of Ag, Au, Cu, or Mg.

[0031] Next, as shown in Figure 1(b), in the immersion step, the prepared precursor materials 11 are immersed in the molten metal 12 contained in the crucible 1. At this time, the components of the molten metal 12 are miscible with the components constituting the second layer 22, but are poorly miscible or improper with the components constituting the first layer 21 than the components constituting the second layer 22. Therefore, the components constituting the second layer 22 can be preferentially dissolved into the molten metal 12. As a result, all or part of the components constituting the second layer 22 of the precursor material 11 dissolve into the molten metal 12 and are replaced by the components of the molten metal 12. In this way, a new laminated member can be formed consisting of the components of the first layer 21, the components of the second layer 22, and the components of the molten metal 12, or a new laminated member consisting of the components of the molten metal 12, in which all or part of the components constituting the second layer 22 of the precursor material 11 have been replaced by the components of the molten metal 12. Therefore, for example, when an existing MAX phase is used as the precursor material 11, a MAX phase with a different A component from the precursor material 11 can be formed as a laminated member.

[0032] Furthermore, by using, for example, a powdered precursor material 11 in the immersion process, a new laminated member can be formed in a few hours to within an hour. This allows for the synthesis of a new laminated member in a shorter time compared to conventional methods such as the molten salt method or the use of precious metals to synthesize a new MAX phase from an existing MAX phase. Also, because synthesis can be done in a short time, bulk material can be used as the precursor material 11 by extending the immersion time in the molten metal 12.

[0033] The resulting laminated member can be easily recovered by removing it from the molten metal 12 and cooling it, or by cooling and solidifying the entire molten metal 12 and then removing the surrounding solidified portion of the molten metal 12.

[0034] Furthermore, by immersing the formed laminated member in molten metal 12 and then solidifying and recovering the molten metal 12, a composite member containing the components of the laminated member and the molten metal 12 can be easily obtained. The obtained composite member can be used in any way.

[0035] Furthermore, in the manufacturing method of the sheet-like member according to the embodiment of the present invention, in the removal step, the obtained laminated member is recovered, and a sheet-like member consisting of the components constituting the first layer 21 is obtained by removing the components constituting the second layer 22 and the components of the molten metal 12, or the components of the molten metal 12, from the recovered laminated member. For example, when the MAX phase is obtained as the laminated member, the laminated member is recovered, and a sheet-like member consisting of MXene material is obtained by removing the components constituting the second layer 22 and the components of the molten metal 12, or the components of the molten metal 12, from the recovered laminated member. In addition, when manufacturing the laminated member, by selecting and using a component that dissolves in an acid or alkaline aqueous solution in advance as the component of the molten metal 12, the components of the molten metal 12 can be removed from the laminated member using that acid or alkaline aqueous solution. This makes it possible to manufacture a sheet-like member easily, quickly, and safely compared to etching with fluorine or molten salt. It is preferable that the acid or alkaline aqueous solution is one that is not harmful even if it remains in the sheet-like member.

[0036] Furthermore, in the manufacturing method of the laminated member according to the embodiment of the present invention, depending on the components of the first layer 21, the second layer 22, and the molten metal 12, by adjusting the immersion time of the precursor material 11 in the molten metal 12 and / or the temperature of the molten metal 12 during the immersion step, some of the components constituting the first layer 21 can also be dissolved into the molten metal 12. As a result, not only the components constituting the second layer 22, but also some of the components constituting the first layer 21 are replaced by components of the molten metal 12, and a laminated member can be obtained in which the components of the molten metal 12 have penetrated and dispersed in the first layer 21. In addition, by removing the components of the molten metal 12 from the laminated member thus obtained in a removal step, a porous sheet-like member can be obtained. [Examples]

[0037] Experiments were conducted to manufacture laminated and sheet-like members using MAX phase Ti3SiC2 as the precursor material 11 and molten Cu as the molten metal 12. Here, the M component of the precursor material 11 is Ti, the A component is Si, and the X component is C. In the experiment, the precursor material 11 was manufactured as follows: First, a powder was produced by ball milling, in which Ti powder, Si powder, and C powder were mixed in a ratio of 3:1:2. Next, the powder was sintered at 1350°C using high frequency and plasma in an Ar atmosphere with a punch pressure of 30 MPa using the discharge plasma sintering (SPS) method. In this way, the Ti3SiC2 precursor material 11 was manufactured.

[0038] As shown in Figure 1(b), the fabricated precursor material 11 was immersed in molten Cu metal 12 at 1100°C in a He atmosphere for 15 minutes. After immersion, the resulting laminated member was removed from the molten metal 12, cooled, and observed. In this case, the heat of mixing between Ti and C is -109 kJ / mol, and the heat of mixing between Ti and Cu is -9 kJ / mol. Therefore, alloying with Ti and C is thermodynamically more stable than alloying with Ti and Cu. Consequently, when the precursor material 11 is immersed in the molten metal 12, Si is more readily dissolved into the molten Cu metal 12 than layers containing Ti and C.

[0039] Figure 2(a) shows an SEM (scanning electron microscope) image of the precursor material 11. Figures 2(b), (c), and 3(a), (b) show SEM images of the obtained laminated member. Figure 2(d) shows the X-ray diffraction spectrum obtained by X-ray diffraction analysis of the laminated member. Figures 3(c)-(e) and 4(a) show STEM (scanning transmission electron microscope) images of the laminated member, and Figure 4(b) shows the elemental analysis results by EDX (energy-dispersive X-ray spectroscopy) along the line in Figure 4(a). In the SEM and STEM images in Figures 2 and 3, the black areas are TiC x In Figure 4(a), the gray and white areas are Cu. Conversely, in Figure 4(a), the black and gray areas are Cu, and the white areas are TiC. x That is the case.

[0040] As shown in Figure 2(a), the precursor material 11 was found to be formed from aggregates of MAX phase particles with a layered structure, and TiC particles were found to be dispersed within them. As shown in Figures 2(b) and 3(a), the obtained laminated member was found to be formed from aggregates of particles having a layered structure, similar to the precursor material 11. Furthermore, as shown in Figure 2(d), the obtained laminated member contained TiC and Cu, but no Si, confirming that Si had been replaced by Cu. It was also confirmed that the composition of Ti and C deviated from Ti3C2. From this, it was found that some of the Ti in Ti3C2 also dissolved into the molten metal, resulting in a Ti concentration of TiC. x The material undergoes a transformation in which a portion of the Ti and C layer is lost and replaced by Cu, and Cu is dispersed within that layer. Furthermore, as shown in Figures 2(b) and 3(a), it was observed that Cu is distributed along the boundaries of the particles, and that TiC particles (the black, lumpy parts) are dispersed, similar to the precursor material 11.

[0041] Furthermore, as shown in Figures 2(c) and 3(b) to 3(e), the resulting laminated member is TiC x It was confirmed that the structure consists of alternating layers of TiC and Cu with a thickness of approximately 100 nm, and even thinner layers with a thickness of a few nm or less. Furthermore, as shown in Figure 4, elemental analysis results also showed that TiC x It was confirmed that the material has a region where layers of the material and layers of Cu are alternately stacked with a thickness of a few nanometers or less.

[0042] These results confirm that a new MAX phase, mainly consisting of a Ti3CuC2 phase, is obtained as a laminated member, in which the Si of the precursor material 11 is replaced with Cu. Furthermore, it can be said that the overall structure of the precursor material 11 is largely maintained in the structure of this laminated member.

[0043] Next, the Cu component of the molten metal 12 was removed from the resulting laminated material using an acid (HCl + CuCl2 + NaCl) to obtain a sheet-like material. SEM images of the obtained sheet-like material are shown in Figures 5(a) to (c). TEM (transmission electron microscope) images of the obtained sheet-like material are shown in Figures 6(a) and (b), and the electron diffraction pattern is shown in Figure 6(c).

[0044] As shown in Figures 5(a) to (c), TiC x It was confirmed that a sheet-like member (MXene) consisting of the above was obtained. Furthermore, as shown in Figure 5(b), it was confirmed that a part of the sheet-like member was porous. This is thought to be because some of the Ti was replaced by Cu, and that Cu was removed. Also, from Figure 6, it was confirmed that the sheet-like member has a face-centered cubic lattice structure (FCC) of TiC x It was confirmed that this was the case. [Examples]

[0045] An experiment was conducted to manufacture a laminated component using MAX phase Ti3AlC2 as the precursor material 11 and molten Ag as the molten metal 12. Here, the M component of the precursor material 11 is Ti, the A component is Al, and the X component is C. In the experiment, the precursor material 11 was manufactured as follows: First, a powder was produced by ball milling, in which Ti powder, Al powder, and C powder were mixed in a ratio of 3:1:2. Next, the powder was sintered at 1300°C using high-frequency and plasma in an Ar atmosphere with a punch pressure of 50 MPa. In this way, the Ti3AlC2 of the precursor material 11 was manufactured.

[0046] First, as shown in Figure 1(b), the fabricated precursor material 11 was immersed in molten Ag metal 12 at 1000°C in a He atmosphere for 10 minutes. After immersion, the resulting laminated member was removed from the molten metal 12, cooled, and observed. In this case, the heat of mixing between Ti and C is -109 kJ / mol, and the heat of mixing between Ti and Ag is -30 kJ / mol. Therefore, alloying with Ti and C is thermodynamically more stable than alloying with Ti and Ag. For this reason, when the precursor material 11 is immersed in the molten metal 12, Al is more readily dissolved into the molten Ag metal 12 than the layer containing Ti and C.

[0047] A scanning electron microscope (SEM) image of the precursor material 11 is shown in Figure 7(a). SEM images of the laminated member after immersion in the molten metal 12 are shown in Figures 7(b) and 8(a). Elemental analysis results by energy-dispersive X-ray spectroscopy (EDX) for the area corresponding to Figure 8(a) are shown in Figures 8(b) to (e). In Figure 7(b), the lighter colored area on the right represents the solidified Ag in the molten metal 12, and the area to the left of that is the obtained laminated member. Figures 8(a) to (e) are reversed left to right compared to Figure 7(b), with the lighter colored area on the left of Figure 8(a) representing the solidified Ag in the molten metal 12, and the area to the right representing the obtained laminated member.

[0048] As shown in Fig. 7(a), it was confirmed that the precursor material 11 was formed by the aggregation of MAX-phase particles with a layered structure, and TiC particles were dispersed therein. Also, as shown in Fig. 7(b), after immersion in the molten metal 12, it was confirmed that the color became lighter up to a range of about 42 μm from the boundary with Ag in the molten metal 12 (the range where the straight line in Fig. 7(b) penetrates). Further, as shown in Figs. 8(a) to (e), it was confirmed that the lighter-colored portion contains Ag, C, and Ti and hardly contains Al. When elemental analysis was performed on the lighter-colored portion (the range surrounded by the rectangle in Fig. 8(b)), it was confirmed that it contains 27.91 at% of C, 53.62 at% of Ti, 16.94 at% of Ag, and 1.53 at% of Al. From these results, it was confirmed that in the lighter-colored portion up to a range of about 42 μm from the boundary with Ag, most of the Al has been replaced by Ag due to immersion in the molten metal 12.

[0049] Next, as shown in Fig. 1(b), the fabricated precursor material 11 of Ti3AlC2 was immersed in a molten Ag at 1100 °C in a He atmosphere for 10 minutes. After immersion, the obtained laminated member was taken out from the molten metal 12 and cooled for observation. The STEM (scanning transmission electron microscope) images of the obtained laminated member are shown in Figs. 9(a) to (f). As shown in Fig. 9, the obtained laminated member has a layered structure, and it was confirmed that layers of TiC x and layers of Ag are alternately laminated with a thickness of several nm or less to about 10 nm. In the STEM image of Fig. 9, the black portions are TiC x and the gray and white portions are Ag.

[0050] From these results, it was confirmed that a new laminated member mainly composed of the Ti3AgC2 phase in which Al of the precursor material 11 has been replaced by Ag has been obtained. At present, since the thickness of the confirmed Ag layer is at least several nm, although the obtained laminated member cannot be said to be a MAX phase, a sheet-like member (MXene) can be obtained by removing Ag from the laminated member.

Example

[0051] Experiments were conducted to manufacture laminated components using MAX phase Ti4SiC3, Ti3CuC2, Ti4CuC3, V2GaC, and V2ZnC as precursor materials 11, and molten Cu, Ag, and Au as molten metals 12. The laminated components manufactured using each precursor material 11 and each molten metal 12 are summarized in Table 1.

[0052] [Table 1]

[0053] The precursor material 11 Ti4SiC3 was manufactured using the same method as the precursor material 11 Ti3SiC2 in Example 1. The precursor material 11 Ti3CuC2 used the laminated member obtained in Example 1, while the precursor material 11 Ti4CuC3 used the laminated member obtained using Ti4SiC3 as the precursor material 11. The precursor materials 11 V2GaC and V2ZnC were manufactured using the same method as the precursor material 11 Ti3SiC2 in Example 1. The immersion time for each precursor material 11 in each molten metal 12 was 10 minutes.

[0054] As shown in Table 1, it was confirmed that, except when the precursor material 11 is V2GaC (component A is Ga) and the molten metal 12 is Ag, a laminated member is obtained in which component A of the MAX phase, which is the precursor material 11, is replaced by a component of the molten metal 12. Furthermore, it was confirmed that when the molten metal 12 is Cu or Au, the resulting laminated member is also the MAX phase. In addition, by removing the component of the molten metal 12 from this MAX phase, sheet-like members (MXene) can be manufactured.

[0055] Furthermore, except when the precursor material 11 is V2GaC (component A is Ga), when the molten metal 12 is Ag, at present, no single-atomic-layer Ag layer has been observed in the obtained laminated member; only a thicker Ag layer has been observed. Therefore, although the obtained laminated member cannot be called the MAX phase, a sheet-like member (MXene) can be obtained by removing Ag from the laminated member.

[0056] In the examples, experiments were conducted to manufacture laminated members and sheet-like members when the precursor material 11 used was a MAX phase of Ti3SiC2 with component A being Si, and a MAX phase of Ti3AlC2 with component A being Al, as well as in the case shown in Table 1. However, laminated members and sheet-like members (MXene) can also be manufactured using, for example, a MAX phase having component A as shown in Table 2 and molten metal 12. In this case, the precursor material 11 is Ti3SiC2, Ti2GaN, Ti3ZnC2, TiCuC x When the precursor material is one of the MAX phases listed in Table 1, by adjusting the immersion time in the molten metal 12 and the temperature of the molten metal 12, some of the Ti in the M component is replaced by components of the molten metal 12, thereby obtaining porous MXene with a large specific surface area. Furthermore, when the precursor material 11 is one of the other MAX phases listed in Table 1, non-porous MXene can be obtained.

[0057] [Table 2] [Explanation of Symbols]

[0058] 1 crucible 11 Precursor materials 21. The first layer 22. Second Layer 12. Molten metal

Claims

1. A step of preparing a precursor material comprising alternating layers of a first layer and a second layer made of a different component from the first layer, The process of preparing a molten metal comprising: a component constituting the second layer being miscible, and a component constituting the first layer being less miscible or more miscible than the component constituting the second layer; The process includes an immersion step in which the precursor material is immersed in the molten metal, thereby causing all or part of the components constituting the second layer to dissolve into the molten metal and form a laminated member replaced by the components of the molten metal, A method for manufacturing a laminated member, characterized by having [a certain characteristic].

2. The method for manufacturing a laminated member according to claim 1, characterized in that the immersion step involves adjusting the time for immersing the precursor material in the molten metal and / or the temperature of the molten metal, so that a portion of the components constituting the first layer also dissolves into the molten metal, thereby forming the laminated member which has been replaced by the components of the molten metal.

3. The aforementioned precursor material is a MAX phase material. The first layer described above has an M component and an X component, The second layer has component A, The aforementioned M component consists of one or more elements from among Sc, Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. The aforementioned component A consists of one or more elements from among Al, Si, P, S, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Cd, In, Sn, Ir, Au, Tl, and Pb. The aforementioned X component consists of one or more elements from B, C, and N. A method for manufacturing a laminated member according to claim 1 or 2, characterized by the present invention.

4. The method for manufacturing a laminated member according to claim 3, characterized in that the molten metal consists of Ag, Au, Cu, or Mg.

5. The aforementioned M component consists of Ti, The aforementioned component A consists of Al or Si. The aforementioned X component consists of C, The molten metal is composed of Ag or Cu. A method for manufacturing a laminated member as described in claim 4.

6. The method for manufacturing a laminated member according to claim 3, characterized in that the heat of mixing between component M and component X is negatively greater than the heat of mixing between component M and the components of the molten metal.

7. A method for manufacturing a laminated member according to claim 1 or 2, characterized by having a recovery step for recovering the laminated member formed in the immersion step.

8. A method for manufacturing a composite member, characterized in that, after the immersion step in the method for manufacturing a laminated member according to claim 1 or 2, the molten metal is solidified and recovered while the formed laminated member is immersed, thereby obtaining a composite member containing the laminated member and the components of the molten metal.

9. A method for manufacturing a sheet-like member, characterized by comprising a removal step of recovering the laminated member formed by the method for manufacturing a laminated member described in claim 1, and removing the components constituting the second layer and the components of the molten metal, or the components of the molten metal, from the recovered laminated member to obtain a sheet-like member.

10. A method for manufacturing a sheet-like member, characterized by comprising a removal step of recovering the laminated member formed by the method for manufacturing a laminated member according to claim 2, and removing the components constituting the second layer and the components of the molten metal, or the components of the molten metal, from the recovered laminated member to obtain a porous sheet-like member.

11. A method for manufacturing a sheet-like member, characterized by comprising a removal step of recovering the laminated member obtained by the method for manufacturing a laminated member according to claim 3, and removing the components constituting the second layer and the components of the molten metal, or the components of the molten metal, from the recovered laminated member to obtain a sheet-like member made of MXene material.

12. The MAX phase material consists of an alloy composed of components M and X, in which layered metal portions in which component A2 is dispersed, and layered portions composed of component A2, are alternately stacked on top of each other. The aforementioned M component consists of one or more elements from among Sc, Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. The aforementioned X component consists of one or more elements from B, C, and N. The aforementioned component A2 consists of Ag, Au, Cu, or Mg. A distinctive laminated component.

13. The laminated members are provided to be covered by a metal covering portion. The laminated member is formed by alternately stacking a layered alloy portion consisting of component M and component X, and a layered portion consisting of component A and component A2, or component A2. Component M consists of one or more elements from Sc, Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; component X consists of one or more elements from B, C, and N; component A consists of one or more elements from Al, Si, P, S, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Cd, In, Sn, Ir, Au, Tl, and Pb; and component A2 consists of Ag, Au, Cu, or Mg. The coating portion is made of the A2 component. Characteristic composite material.

14. The laminated member according to claim 12 is provided to be covered by a covering portion made of metal, The coating portion is made of the A2 component. Characteristic composite material.

15. It is porous and consists of MXene material containing components M and X. The aforementioned M component consists of one or more elements from among Sc, Ti, V, Cr, Mn, Zr, Nb, Mo, Hf, Ta, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. The aforementioned X component consists of one or more elements from B, C, and N. A characteristic sheet-like member.

Images