Two-dimensional cubic multilayer titanium nitride material and preparation method and application thereof

Abstract

This invention belongs to the field of inorganic materials technology, and relates to a two-dimensional cubic multilayer titanium nitride material, its preparation method, and its applications. The molecular formula of the two-dimensional cubic multilayer titanium nitride material is TiN. α Where 0 < α ≤ 1; the preparation method of the two-dimensional cubic multilayer titanium nitride material includes the following steps: mixing Ti4AlN3 material and anhydrous copper chloride, and then heating and reacting under an inert atmosphere to obtain the two-dimensional cubic multilayer titanium nitride material. The preparation method proposed in this invention is simple to operate, easy to prepare on a large scale in industrial applications, and the two-dimensional cubic multilayer titanium nitride material obtained using economical and environmentally friendly raw materials has a high specific surface area and good high-temperature stability, showing good application prospects in catalysis, energy storage, electromagnetic shielding and other fields.

Description

Technical Field

[0001] This invention belongs to the field of inorganic materials technology, and relates to a two-dimensional cubic multilayer titanium nitride material, its preparation method and application. Background Technology

[0002] Two-dimensional titanium nitride (TiN) is a type of two-dimensional layered material with excellent photoelectric properties and a high specific surface area. The successful preparation of two-dimensional TiN materials through effective methods will greatly advance their application in catalyst supports, lithium-sulfur batteries, and molten salt electrolysis electrodes. The successful exfoliation of a series of two-dimensional materials, such as graphene, boron nitride (hBN), and transition metal sulfides (TMDs), in the liquid phase demonstrates that the "top-down" route is an effective method for synthesizing two-dimensional materials. However, compared to the aforementioned van der Waals force layered materials, titanium nitride atoms are strongly bonded together by chemical bonds, making it impossible to directly exfoliate the two-dimensional structure using liquid-phase methods.

[0003] In recent years, the emergence of a class of two-dimensional transition metal carbonitride materials (MXenes) has provided a new "top-down" synthesis approach. MXenes can be obtained by selectively etching the single-atom A layer of ternary layered transition metal carbonitride materials (MAX phase, where M is a pre-transition metal, A is mainly a group IIIA or IVA element, and X is carbon or nitrogen). For MAX phase materials containing Ti and N elements, such as Ti2AlN and Ti4AlN3, the corresponding two-dimensional hexagonal Ti2NT can be obtained by selectively etching the Al atomic layer. x and Ti4N3T x MXenes material.

[0004] However, existing preparation methods yield low-purity two-dimensional titanium nitrides, the products are unstable at high temperatures, and all synthetic routes involve harmful fluorides. Therefore, finding a green, safe, and high-purity synthesis method is crucial for the preparation of two-dimensional titanium nitride. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a two-dimensional cubic multilayer titanium nitride material, its preparation method, and its applications.

[0006] One objective of this invention is achieved through the following technical solution:

[0007] A two-dimensional cubic multilayer titanium nitride material, wherein the molecular formula of the two-dimensional cubic multilayer titanium nitride material is TiN. α Where 0 < α ≤ 1. Preferably, 0 < α < 1.

[0008] Furthermore, the two-dimensional cubic multilayer titanium nitride material has a face-centered cubic crystal structure, with the N element located in the octahedral voids of the Ti element.

[0009] Furthermore, the two-dimensional cubic multilayer titanium nitride material has an accordion-like morphology, formed by stacking two-dimensional sheets to form an accordion shape, with gaps between the two-dimensional sheets.

[0010] Furthermore, the two-dimensional sheets consist of a single layer or multiple layers of TiN. α The two-dimensional sheet has a lateral dimension of 5 nm to 50 μm and a thickness of 1 to 100 nm, preferably 1 to 50 nm.

[0011] Furthermore, the surface of the two-dimensional cubic multilayer titanium nitride material contains a small amount of Cl element, which is bonded to Ti atoms.

[0012] Another objective of this invention is achieved through the following technical solution:

[0013] A method for preparing a two-dimensional cubic multilayer titanium nitride material includes the following steps: mixing Ti4AlN3 material and anhydrous copper chloride, and then heating and reacting them under an inert atmosphere to obtain the two-dimensional cubic multilayer titanium nitride material.

[0014] This invention employs a strategy of combining high-temperature molten salt etching with high-temperature phase transformation. Ti4AlN3 is selected as the precursor material for the reaction, and copper chloride is used as the etchant to selectively etch away the Al elements between the Ti4AlN3 layers. The etched product undergoes a phase transformation at high temperature, transforming into a cubic two-dimensional cubic multilayer titanium nitride.

[0015] Furthermore, the Ti4AlN3 material is any one or a combination of two or more of the following: powder, bulk, and thin film; the anhydrous copper chloride has a purity of 98 wt.% or higher.

[0016] Furthermore, the molar ratio of Ti4AlN3 material to anhydrous copper chloride is 1:3 to 1:7.5.

[0017] Further optimization yielded a molar ratio of Ti4AlN3 material to anhydrous copper chloride of 1:3 to 1:5. When the content of anhydrous copper chloride was too low, the product contained significant impurities from other phases; while when the content of anhydrous copper chloride was too high, it had no effect on the preparation of the two-dimensional cubic multilayer titanium nitride material, but would result in a waste of raw materials.

[0018] Furthermore, the reaction temperature is heated to 750–950 °C. When the reaction temperature is equal to or below 600 °C, the product obtained is Ti₄N₃T. x MXene impurities are detrimental to the formation of two-dimensional cubic multilayer titanium nitride materials; and reaction temperatures above 950℃ will cause the vaporization loss of the reaction raw material copper chloride, which is also detrimental to the formation of two-dimensional cubic multilayer titanium nitride materials.

[0019] Furthermore, the heating reaction time is 0.5~10h, more preferably 1~10h, 2~10h.

[0020] Furthermore, in the above preparation method, after the heating reaction, a post-treatment is performed, which includes the following steps: after the heating reaction is completed, Cu element in the product is removed, and the reaction product is washed with water and then dried to finally obtain a two-dimensional cubic multilayer titanium nitride material.

[0021] Furthermore, in the post-processing step, the product is placed in an aqueous solution of ammonium persulfate or dilute nitric acid to remove elemental Cu from the product.

[0022] Another objective of this invention is achieved through the following technical solution:

[0023] The above-mentioned two-dimensional cubic multilayer titanium nitride materials are used in catalysis, energy storage, and electromagnetic shielding.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The two-dimensional cubic multilayer titanium nitride material provided by the present invention has an accordion-like morphology similar to MXene material and is a face-centered cubic crystal form. The two-dimensional cubic multilayer titanium nitride material has the excellent properties of MXene material, and also has the characteristic of being more resistant to high temperature than MXene material.

[0026] 2. The two-dimensional cubic multilayer titanium nitride material provided by this invention has a high specific surface area and good high temperature stability, and has broad application prospects in the fields of catalyst support, lithium-sulfur battery, electromagnetic shielding, and molten salt electrolysis electrode.

[0027] 3. In this invention, Ti4AlN3 is used as the precursor material for the reaction and copper chloride is used as the etching agent. The product prepared therefrom undergoes a phase transformation at high temperature to generate cubic two-dimensional cubic multilayer titanium nitride.

[0028] 4. The TiN prepared by this invention α The product has higher purity, and the preparation process is green, safe, and has low raw material costs, making it easier to scale up for industrial production. Attached Figure Description

[0029] Figure 1 The Ti4AlN3 raw material and TiN in Example 1 of this invention α XRD pattern of the product;

[0030] Figure 2 It is TiN in Embodiment 1 of the present invention α SEM image of the product;

[0031] Figure 3a and Figure 3b It is TiN in Embodiment 1 of the present invention α SEM and EDS images of the product;

[0032] Figure 4 It is TiN in Embodiment 1 of the present invention α High-resolution transmission electron microscopy image of the product;

[0033] Figure 5 These are the XRD patterns of the products obtained under different reaction conditions in Example 2 of this invention;

[0034] Figure 6 These are the XRD patterns of the products obtained under different reaction conditions in Example 3 of this invention. Detailed Implementation

[0035] The technical solution of the present invention will be further described and illustrated below with reference to specific embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are only for the purpose of helping to understand the present invention and are not intended to limit the specific scope of the present invention. Furthermore, the accompanying drawings used herein are merely for better illustrating the content disclosed in the present invention and do not limit the scope of protection. Unless otherwise specified, the raw materials used in the embodiments of the present invention are all commonly used in the art, and the methods used in the embodiments are all conventional methods in the art.

[0036] Example 1

[0037] In this embodiment, the two-dimensional cubic multilayer titanium nitride material is a powder material, and the raw materials are Ti4AlN3 powder, anhydrous copper chloride powder and ammonium persulfate. These raw materials can all be obtained through commercial channels.

[0038] The specific preparation method of this two-dimensional multilayer titanium nitride material powder is as follows:

[0039] (1) Weigh 1.04 g of 500 mesh Ti4AlN3 powder and 2.08 g of anhydrous copper chloride with a purity of 98 wt.%, grind and mix the above raw materials to obtain a mixed product;

[0040] (2) Place the mixed product in a corundum crucible and heat it in a high-temperature tube furnace under argon protection. The heating conditions are: 750 °C for 300 min. After the temperature of the tube furnace drops to room temperature, take out the reaction product from the crucible.

[0041] (3) The reaction product after extraction was placed in 100 mL of 0.1 M ammonium persulfate aqueous solution and stirred for one hour to remove Cu from the product. The product was then washed with deionized water and dried at 50 °C to obtain a two-dimensional multilayer titanium nitride material.

[0042] Figure 1Two-dimensional cubic multilayer titanium nitride (TiN) prepared in Example 1 α XRD patterns of the powdered product and Ti4AlN3 raw material showed that TiN α It has a face-centered cubic crystal structure and exhibits broadened diffraction peaks. Figure 2 TiN α The SEM images reveal the accordion-like morphology, formed by the stacking of two-dimensional sheets with gaps between them. This is similar to the morphological characteristics of two-dimensional transition metal carbonitride (MXenes) materials. Combined with the broadened diffraction peaks, this further indicates that TiN... α Two-dimensional and multi-layered properties. Figure 3a and Figure 3b TiN from Example 1 α The SEM images and corresponding EDS spot scan results of the product show that TiN α The atomic ratio of Ti:N = 28.5:28.4, with O (33.5 at.%), C (7.3 at.%), and a small amount of Cl (2.3 at.%), confirms that TiN... α Elemental composition.

[0043] Figure 4 TiN α The high-resolution transmission electron microscopy images show that the interplanar spacings of 0.215 nm and 0.245 nm, and the interplanar angle of 54°, are consistent with the interplanar spacings and interplanar angles of the (020) and (111) planes of cubic TiN, corresponding to TiN α of The zone axis further confirms the presence of TiN. α It has a face-centered cubic crystal structure.

[0044] Example 2

[0045] In this embodiment, two-dimensional multilayer titanium nitride materials were prepared using four different raw material ratio schemes to study the influence of the raw material ratio. The prepared two-dimensional multilayer titanium nitride materials were powder materials, and the raw materials were Ti4AlN3 powder, anhydrous copper chloride powder, and ammonium persulfate. These raw materials can all be obtained through commercial channels. The specific steps and raw material ratios of the four schemes are as follows:

[0046] (1) Weigh 500 mesh Ti4AlN3 powder and anhydrous copper chloride with a purity of 98 wt.% according to the proportions in Table 1, grind and mix them separately to obtain the mixed products of the four schemes;

[0047] Table 1

[0048]

[0049] (2) The mixtures of the four schemes were placed in four different corundum crucibles and heated in a high-temperature tube furnace under argon protection. The heating conditions were: 750 °C for 300 min. After the temperature of the tube furnace dropped to room temperature, the reaction products in the crucibles were taken out.

[0050] (3) The reaction products of the four schemes were placed in 100 mL of 0.1 M ammonium persulfate aqueous solution and stirred for one hour to remove Cu from the products. The reaction products of the four schemes were washed with deionized water and then dried at 50 °C to finally obtain the reaction products of the four schemes.

[0051] Figure 5 The XRD patterns of the products obtained from the four methods show that the preparation of TiN α The optimal raw material ratio is 1:3 to 1:5. When the content of anhydrous copper chloride is lower than this ratio, the product contains significant impurities of other phases, such as the product of Scheme 1 (1:1.5-750℃). When the content of anhydrous copper chloride is higher than this ratio, it has no effect on the preparation of two-dimensional multilayer titanium nitride materials, such as Scheme 4 (1:7.5-750℃), but it will result in a waste of raw materials.

[0052] Example 3

[0053] In this embodiment, two-dimensional multilayer titanium nitride materials were prepared using four different heating temperatures to study the effect of heating temperature. The prepared two-dimensional multilayer titanium nitride materials were powder materials, and the raw materials were Ti4AlN3 powder, anhydrous copper chloride powder, and ammonium persulfate, all of which can be obtained through commercial means. The specific steps and heating temperatures of the four methods are as follows:

[0054] (1) Weigh 1.04 g of 500 mesh Ti4AlN3 powder and 2.68 g of anhydrous copper chloride with a purity of 98 wt.% respectively, grind and mix the above 4 groups of materials to obtain 4 mixed products;

[0055] (2) The four mixed products were placed in four different corundum crucibles and then placed in high-temperature tube furnaces for heating under argon protection. The heating temperatures of the four mixed products are shown in Table 2 below. After the temperature of the tube furnace dropped to room temperature, the reaction products in the crucibles were taken out.

[0056] Table 2

[0057]

[0058] (3) The reaction products of the four schemes were placed in 100 mL of 0.1 M ammonium persulfate aqueous solution and stirred for one hour to remove Cu from the products. The reaction products of the four schemes were washed with deionized water and then dried at 50 °C to finally obtain the reaction products of the four schemes.

[0059] Figure 6 The XRD patterns of the products obtained from the four methods show that the preparation of TiN α The optimal synthesis temperature is 750–950 °C. Reactions at or below 600 °C yield the product Ti₄N₃T. x MXene impurity phase (Ti4N3T) x MXene has a hexagonal crystal form (different from the cubic crystal form of this invention), as shown in Scheme 2, which is unfavorable for the formation of two-dimensional multilayer titanium nitride materials. Synthesis temperatures above 950 °C cause the reactant copper chloride to boil, which is also detrimental to the formation of two-dimensional multilayer titanium nitride materials. Furthermore, the high synthesis temperature of 950 °C also indicates that the two-dimensional cubic titanium nitride material has good high-temperature stability.

[0060] All aspects, embodiments, and features of this invention should be considered illustrative in all respects and not limiting of the invention; the scope of the invention is defined only by the claims. Other embodiments, modifications, and uses will become apparent to those skilled in the art without departing from the spirit and scope of the invention as claimed.

[0061] In the preparation method of this invention, the order of the steps is not limited to the listed order. For those skilled in the art, variations in the order of the steps without creative effort are also within the scope of protection of this invention. Furthermore, two or more steps or actions can be performed simultaneously.

[0062] Finally, it should be noted that the specific embodiments described herein are merely illustrative examples of the invention and are not intended to limit the implementation of the invention. Those skilled in the art can make various modifications or additions to the described specific embodiments or use similar methods to replace them; it is neither necessary nor possible to exemplify all embodiments here. However, these obvious variations or modifications derived from the essential spirit of the invention still fall within the scope of protection of the invention, and interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A two-dimensional cubic multilayer titanium nitride material, characterized in that, The molecular formula of the two-dimensional cubic multilayer titanium nitride material is TiN. α , where 0<α≤1; the two-dimensional cubic multilayer titanium nitride material is face-centered cubic, and the N element is located in the octahedral voids of the Ti element; The preparation method of two-dimensional cubic multilayer titanium nitride material includes the following steps: mixing Ti4AlN3 material and anhydrous copper chloride in a molar ratio of 1:3 to 1:7.5, heating the mixture under an inert atmosphere at a temperature of 750 to 950°C for 0.5 to 10 hours to obtain two-dimensional cubic multilayer titanium nitride material.

2. The two-dimensional cubic multilayer titanium nitride material according to claim 1, characterized in that, The two-dimensional cubic multilayer titanium nitride material has an accordion-like morphology, formed by stacking two-dimensional sheets to form an accordion shape, with gaps between the two-dimensional sheets.

3. The two-dimensional cubic multilayer titanium nitride material according to claim 2, characterized in that, The lateral dimensions of the two-dimensional sheet are 5nm~50μm, and the thickness of the two-dimensional sheet is 1~100nm.

4. The two-dimensional cubic multilayer titanium nitride material according to claim 1, characterized in that, The surface of the two-dimensional cubic multilayer titanium nitride material contains Cl elements, which are bonded to Ti atoms.

5. The method for preparing a two-dimensional cubic multilayer titanium nitride material as described in claim 1, characterized in that, The process includes the following steps: mixing Ti4AlN3 material and anhydrous copper chloride in a molar ratio of 1:3 to 1:7.5, heating the mixture under an inert atmosphere at a temperature of 750 to 950°C for 0.5 to 10 hours to obtain a two-dimensional cubic multilayer titanium nitride material.

6. The preparation method according to claim 5, characterized in that, The molar ratio of Ti4AlN3 material to anhydrous copper chloride is 1:3 to 1:

5.

7. The application of the two-dimensional cubic multilayer titanium nitride material as described in claim 1 in the fields of catalysis, energy storage, and electromagnetic shielding.

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