One-dimensional non-Van der Waals superlattice material, preparation method thereof, thin film, preparation system and application in electromagnetic shielding

Abstract

The invention discloses a one-dimensional non-Van der Waals superlattice material, a preparation method thereof, a thin film, a preparation system and application in electromagnetic shielding. The non-van der Waals superlattice is formed by periodically stacking MXene atomic layers through a stiffness-mediated curling strategy, and strong electron coupling is formed between the layers through hydrogen bonds. The superlattice material has Moire periodicity, shows ultrahigh conductivity, and meanwhile has high charge carrier concentration and unique positive linear magnetoresistance characteristics. When the thin film is applied to electromagnetic interference shielding, the thin film can achieve shielding effectiveness exceeding 124dB. According to the method, metal vacancies are created in the MXene material to customize the bending rigidity, rapid and ordered curling is achieved through a specific stripping agent, and various non-Van der Waals superlattices including V, Ti, Nb and Ta-based carbides and carbonitride are successfully prepared. The method is high in yield and good in reproducibility, and a brand new material platform is provided for developing high-performance electronic and electromagnetic shielding and energy devices.

Description

Technical Field

[0001] This invention belongs to the field of new materials, and in particular relates to a one-dimensional non-van der Waals superlattice material, its preparation method, thin film, preparation system, and its application in electromagnetic shielding. Background Technology

[0002] Artificial superlattices, especially those constructed from two-dimensional atomic layers through layer-by-layer stacking or sequential epitaxial growth, have become an important platform for developing next-generation electronic, photonic, and energy devices due to their ability to generate entirely new physical and chemical properties that surpass those of their constituent materials. To date, the vast majority of research and practice has focused on van der Waals (vdW) superlattices. These superlattices originate from layered materials such as graphene and transition metal sulfides (e.g., MoS2), where the interlayers are held together by relatively weak van der Waals forces.

[0003] Based on their structure and composition, existing artificial superlattices can be mainly divided into Moiré superlattices and heterostructure superlattices. Moiré superlattices, formed by stacking two or more layers of atomic crystals at a specific twist angle, have exhibited novel physical phenomena such as unconventional superconductivity, ferromagnetism, and related insulating states. Heterostructure superlattices, on the other hand, are composed of two or more different two-dimensional atomic layers stacked periodically in alternation, exhibiting unique electrical and magnetic properties and showing broad application prospects in electronics, energy storage, and catalysis.

[0004] Currently, common strategies for constructing such van der Waals superlattices mainly include manual stacking layer by layer after mechanical exfoliation, or sequential epitaxial growth via methods such as chemical vapor deposition (CVD). However, these methods all have inherent limitations. First, the layer-by-layer stacking process is cumbersome, time-consuming, and heavily reliant on the operator's experience, resulting in extremely low yields and poor reproducibility, making large-scale fabrication difficult. Second, whether manual stacking or epitaxial growth, the available precursor materials are limited to the inherent layered van der Waals crystals, severely restricting material sources. More importantly, the interlayer coupling dominated by van der Waals forces is weak, which limits the effective hybridization of interlayer electronic states, thus restricting further improvements in key electronic properties of superlattices such as conductivity and carrier mobility.

[0005] To overcome the limitations of material sources, researchers have recently begun exploring the preparation of two-dimensional atomic layers from non-van der Waals solids (such as MAX phases), such as MXenes. MXenes are a class of two-dimensional materials composed of transition metal carbides, nitrides, or carbonitrides, typically obtained by selectively etching the atom layers in MAX phases. Although the MXene family greatly enriches the diversity of two-dimensional materials, current techniques mainly focus on the preparation and application of their two-dimensional nanosheet morphology. How to further assemble these non-van der Waals two-dimensional materials into novel superlattices with periodically ordered structures and achieve strong interlayer coupling remains a significant challenge. Traditional exfoliating agents and methods (such as small molecules or common quaternary ammonium bases) often only achieve simple exfoliation and dispersion of MXenes, making it difficult to induce their controllable self-assembly to form long-range ordered superlattice structures.

[0006] Therefore, there is an urgent need in this field to develop a novel synthesis strategy that can overcome the dual limitations of existing van der Waals superlattices in terms of material source and interfacial coupling strength, and achieve efficient and controllable preparation of non-van der Waals superlattices with rich chemical composition, strong interfacial coupling and excellent performance. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a novel superlattice material, its preparation method, and its application. To achieve the above objective, this invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a one-dimensional non-van der Waals superlattice material. It is formed by helically coiling at least one two-dimensional atomic layer, with adjacent layers of said atomic layer coupled by hydrogen bonds. For example... Figure 1 Figure a shows a schematic diagram of the formation of a one-dimensional non-van der Waals superlattice.

[0009] In some embodiments, the two-dimensional material described above is a transition metal carbide, a carbonitride, or a combination thereof.

[0010] In some embodiments, the two-dimensional material described above is MXene.

[0011] In some embodiments, the general formula of the above-mentioned MXene is M n+1 X n T x Where M is at least one transition metal, X is at least one of carbon, nitrogen, or boron, and T x This indicates the presence of surface functional groups, where 1 ≤ n ≤ 3.

[0012] In some embodiments, the general formula of the above-mentioned MXene is M2XT. x M3X2T x Or M4X3T x .

[0013] In some embodiments, the general formula of the above MXene is (M' 2-m M” m )XT x , where m is a non-zero real number between 0 and 2, and M' and M” are two different transition metals.

[0014] In some embodiments, the transition metal is selected from at least one or two of vanadium (V), titanium (Ti), niobium (Nb), tantalum (Ta), scandium (Sc), manganese (Mn), chromium (Cr), molybdenum (Mo), tungsten (W), zirconium (Zr), and hafnium (Hf).

[0015] In some embodiments, the interlayer spacing between adjacent atomic layers is 0.8 nm to 2.0 nm; preferably, the interlayer spacing is 1.10 nm to 1.20 nm.

[0016] In some embodiments, the inner radius of the aforementioned one-dimensional non-van der Waals superlattice material is between 5 nm and 100 nm; preferably, the inner radius is between 10 nm and 50 nm.

[0017] In some embodiments, the aspect ratio of the aforementioned one-dimensional non-van der Waals superlattice material is between 5 and 100.

[0018] In some embodiments, the material has a moiré superlattice structure; preferably, the moiré superlattice structure has an interlayer twist angle between 2° and 30°.

[0019] In some embodiments, the aforementioned hydrogen bond coupling is confirmed by a redshift of the -OH bond vibration peak in the Fourier transform infrared spectrum; preferably, the -OH bond vibration peak is located at 3420 cm⁻¹. -1 Up to 3430cm -1 Within the wavenumber range.

[0020] In some embodiments, the electrical conductivity of the above material at a temperature of 300K is not less than 10,000 S cm. -1 Preferably, the electrical conductivity is not less than 20,000 S cm⁻¹. -1 More preferably, not less than 30,000 S cm -1 .

[0021] In some embodiments, the charge carrier concentration of the above-described material is not less than 1 × 10⁻⁶. 21 cm -3 ;

[0022] In some embodiments, the above-described material exhibits a positive linear magnetoresistance effect.

[0023] A second aspect of the present invention provides a method for preparing the above-mentioned one-dimensional non-van der Waals superlattice material, characterized by comprising the following steps: a) providing a multilayer two-dimensional material; b) processing the multilayer two-dimensional material to reduce the bending stiffness of its atomic layers; c) contacting the processed multilayer two-dimensional material with a stripping agent, thereby stripping and curling the atomic layers to form a one-dimensional non-van der Waals superlattice structure.

[0024] In some embodiments, the step of “processing a multilayer two-dimensional material to reduce the bending stiffness of its atomic layers” is achieved by introducing vacancies in the atomic layers; preferably, the vacancies are transition metal vacancies.

[0025] In some embodiments, the aforementioned vacancies are introduced by chemical etching; preferably, the chemical etching uses a fluoride-containing etchant; more preferably, the etchant is a mixed solution of hydrochloric acid and a fluoride salt, or a hydrofluoric acid solution.

[0026] In some embodiments, the reaction temperature of the above chemical etching is from room temperature to 95°C, and the reaction time is from 4 to 96 hours.

[0027] In some embodiments, the aforementioned vacancies are introduced by using a precursor material having a vacancy or solid solution structure.

[0028] In some embodiments, the precursor is a MAX phase with the general chemical formula M. n+1 AX n Where M is at least one transition metal, A is a group 13-16 element, X is at least one of carbon, nitrogen, and boron, 1≤n≤3; and there is a vacancy at the M site or a solid solution is formed by at least two transition metals.

[0029] In some embodiments, the precursor is a MAX phase and its general formula is M2AX, M3AX2 or M4AX3.

[0030] In some embodiments, the above MAX phase is (M' 2-m M” m )AX, where m is a non-zero real number between 0 and 2, and M' and M” are two different transition metals.

[0031] In some embodiments, the transition metal is selected from at least one or two of vanadium (V), titanium (Ti), niobium (Nb), tantalum (Ta), scandium (Sc), manganese (Mn), chromium (Cr), molybdenum (Mo), tungsten (W), zirconium (Zr), and hafnium (Hf).

[0032] In some embodiments, the stripping agent is a compound having a large molecular size and low surface tension; the molecular size of the stripping agent is not less than... More preferably, not less than The surface tension of the compound is ≤40 mN / m -1 More preferably, ≤35mN m -1 .

[0033] In some embodiments, the stripping agent is a quaternary phosphorus base or a quaternary ammonium base; preferably, the stripping agent is tetrabutylphosphine hydroxide (TBPH).

[0034] In some embodiments, the above-described "contact" step completes the peeling and curling of the atomic layer within 0.1 seconds to 60 seconds.

[0035] In some embodiments, the “contact” step described above is performed with the aid of stirring or ultrasound.

[0036] In some embodiments, the above method further includes the steps of washing, centrifuging and / or drying the resulting one-dimensional non-van der Waals superlattice material after curling.

[0037] A third aspect of the present invention provides an electromagnetic interference shielding component, the component comprising the one-dimensional non-van der Waals superlattice material described above; or, the one-dimensional non-van der Waals superlattice material obtained by the above method.

[0038] In some embodiments, the aforementioned one-dimensional non-van der Waals superlattice material serves as the primary electromagnetic wave attenuation phase in the component.

[0039] In some embodiments, the components described above are in the form of a thin film, coating, foam, or bulk composite material.

[0040] In some embodiments, the above-mentioned component is in the form of a thin film; preferably, the thickness of the thin film is between 1 μm and 100 μm.

[0041] In some embodiments, the one-dimensional non-van der Waals superlattice material in the above-described thin film is randomly distributed.

[0042] In some embodiments, the one-dimensional non-van der Waals superlattice material in the above-described thin film is preferentially oriented along at least one direction.

[0043] In some embodiments, the film is a sandwich structure, comprising a highly oriented layer in the middle and two randomly distributed layers on both sides of the highly oriented layer.

[0044] And / or, the Hermann orientation factor of the thin film is not less than 0.8.

[0045] In some embodiments, the total electromagnetic interference shielding effectiveness (SE) of the above-described components in the frequency range of 8.2 GHz to 12.4 GHz is... T Not less than 80dB; preferably, not less than 100dB, more preferably, not less than 120dB;

[0046] In some embodiments, the absorption and shielding effectiveness SE of the above-described components A SE accounts for the total shielding effectiveness T More than 50%;

[0047] In some embodiments, the electrical conductivity of the above-described component is not less than 5,000 S cm⁻¹. -1 Preferably, it is not less than 10,000 Scm -1 ;

[0048] In some embodiments, the absolute shielding effectiveness (SSE / t) of the above-described components is not less than 50,000 dB cm. 2 g -1 Not less than 100,000 dB cm 2 g -1 More preferably, not less than 150,000 dB cm⁻¹ 2 g -1 .

[0049] In some embodiments, the component is in the form of a thin film, exhibiting flexibility and bendability.

[0050] In some embodiments, the above-described components further comprise a polymer matrix in which the one-dimensional non-van der Waals superlattice material is dispersed in or on the surface of the polymer matrix to form a composite shielding material.

[0051] In some embodiments, the conductivity of the component decreases by no more than 20% after 10,000 bending cycles.

[0052] The fourth aspect of this invention provides the use of the above-mentioned one-dimensional non-van der Waals superlattice material in the preparation of electromagnetic interference shielding materials.

[0053] A fifth aspect of the present invention provides a system for preparing a one-dimensional nanomaterial oriented film, comprising: a storage unit for holding a dispersion containing one-dimensional nanomaterials; an extrusion unit in fluid communication with the storage unit for extruding the dispersion; an orientation unit including a slit channel configured to receive the dispersion extruded from the extrusion unit and orient the one-dimensional nanomaterials in the dispersion along a flow direction by an applied shear force; and a receiving unit for receiving the oriented dispersion extruded from the slit channel and forming it into a solid or semi-solid film.

[0054] In some embodiments, the one-dimensional nanomaterial is the one-dimensional non-van der Waals superlattice material described above.

[0055] In some embodiments, the concentration of one-dimensional nanomaterials in the dispersion is not less than 100 mg / mL.

[0056] In some embodiments, the dispersion has liquid crystal properties.

[0057] In some embodiments, the dispersion exhibits shear-thinning rheological properties.

[0058] In some embodiments, the extrusion unit includes an injection pump, a screw extruder, or a pneumatic drive.

[0059] In some embodiments, the outlet of the slit channel is a flat needle or a straight slit mold; preferably, the slit width of the flat needle or straight slit mold is between 10 μm and 1000 μm.

[0060] In some embodiments, the receiving unit includes a translation platform or a rotating roller, which is configured to move at a controllable speed to receive the oriented dispersion.

[0061] In some embodiments, the receiving unit further includes a heating device or a drying device for promoting the solidification of the dispersion.

[0062] In some embodiments, the system further includes a flexible substrate disposed on the receiving unit, wherein the oriented dispersion is extruded onto the flexible substrate to form a thin film.

[0063] In some embodiments, the system further includes a control unit communicatively connected to the extrusion unit and / or the receiving unit, the control unit being configured to control at least one of the extrusion speed, the receiving speed, and the distance between the extrusion port and the receiving surface.

[0064] In some embodiments, the control unit is configured to coordinate the extrusion speed with the receiving speed to maintain a stable shear rate and film thickness.

[0065] The sixth aspect of the present invention provides a method for preparing one-dimensional nanomaterial oriented thin films, characterized in that the above-described system is used.

[0066] The seventh aspect of the present invention provides a one-dimensional nanomaterial orientation film, characterized in that it is prepared by the method described above.

[0067] The eighth aspect of the present invention provides a one-dimensional nanomaterial orientation film, characterized in that the one-dimensional nanomaterial orientation film is formed by an ordered arrangement of one-dimensional nanomaterials along a specific direction, wherein the one-dimensional nanomaterials are the aforementioned one-dimensional non-van der Waals superlattice materials.

[0068] In some embodiments, the Hermann orientation factor of the above-mentioned one-dimensional nanomaterial orientation film is not less than 0.7; more preferably, not less than 0.8; and even more preferably, not less than 0.85.

[0069] In some embodiments, the ratio of the conductivity of the above-mentioned one-dimensional nanomaterial oriented thin film parallel to the specific direction to the conductivity perpendicular to the specific direction satisfies: ≥2, preferably ≥5;

[0070] In some embodiments, the in-plane conductivity of the above-mentioned one-dimensional nanomaterial oriented thin film is not less than 5,000 S cm⁻¹. -1 Preferably, it is not less than 10,000 S cm -1 More preferably, not less than 20,000 S cm -1 .

[0071] The ninth aspect of the present invention provides an electromagnetic interference shielding component, wherein the above-mentioned one-dimensional nanomaterial oriented thin film is provided.

[0072] The tenth aspect of the present invention provides an electronic device or apparatus comprising the above-described one-dimensional van der Waals superlattice material, electromagnetic interference shielding component, or one-dimensional nanomaterial oriented thin film.

[0073] In some embodiments, the electronic device or apparatus described above is a sensor, chip, mobile phone, base station, laptop computer, wearable device, automobile, ship, aerospace vehicle or military radar.

[0074] Compared with the prior art, the present invention has the following significant advantages:

[0075] (1) This invention creatively fabricates a non-van der Waals superlattice coupled by hydrogen bonds, breaking the material limitations of traditional van der Waals superlattices. This structure endows the material with extremely high electrical conductivity (up to approximately 30,000 S cm⁻¹). -1 (22 times higher than its sheet) and a high concentration of charge carriers (approximately 10 22 cm -3 It exhibits a unique positive linear magnetoresistance effect.

[0076] (2) Strong interfacial coupling. The presence of interlayer hydrogen bonds provides interfacial coupling that is much stronger than van der Waals forces, promoting strong correlation of interlayer electrons. This is the structural basis for its excellent electrical performance and also enhances the stability of the structure.

[0077] (3) The method is efficient and has strong universality. The "stiffness-mediated curling" preparation strategy proposed in this invention customizes the bending stiffness by controlling the vacancies and uses a large-size stripping agent to trigger rapid and orderly curling. The method is simple and efficient, with high yield (up to 96%), good reproducibility, and is applicable to carbides and carbonitrides of various transition metals such as V, Ti, Nb, and Ta. It has successfully constructed a superlattice family of MXene containing 17 members, and the platform has extremely strong scalability.

[0078] (4) When the superlattice material of the present invention is used for electromagnetic interference shielding, one of the highest shielding performances (up to 124dB) of the same thickness can be obtained to date. Its absolute shielding performance (SSE / t) far exceeds that of existing mainstream materials (such as copper foil and traditional MXene film), providing a new generation of high-performance solutions for solving the increasingly serious electromagnetic pollution problem of modern electronic devices.

[0079] (5) Through the aforementioned dedicated equipment system, a macroscopically ordered arrangement of superlattices on a one-dimensional scale can be achieved, and highly oriented thin films can be prepared, thereby obtaining better conductivity and shielding performance in a specific direction to meet the needs of anisotropic functional devices. Attached Figure Description

[0080] Figure 1 This is a schematic diagram of the formation of a one-dimensional non-van der Waals superlattice; where (a) represents the stable state (total formation energy E). f ≤0) monolayer (M2XT) x (a) is a coiled model where hydrogen bonds exist between adjacent atomic layers (dashed lines); (b) is an atomic layer (V2CT) x The inner radius (R) of ) in (c) Bending stiffness (D) relationship diagram, dividing the region into two areas: curled (red) and nanosheet (blue); (d) for various MXene curls (including M2XT) x M3X2T x M4X3T x Theoretical bending stiffness (D) T ) and the corresponding minimum inner radius (R) m Summary diagram, with an inset showing the transformation of multilayer MXene into a coiled structure under the action of tetrabutylphosphine hydroxide (TBPH).

[0081] Figure 2 (a) represents V2CT x (a) TEM image of the superlattice, showing a rolled-up morphology and good monodispersity; (b) a single V2CT. x The magnified TEM image of the superlattice and the corresponding line outline shown in the inset of (b) reveal that it is a hollow structure with a constant interlayer spacing of approximately 1.14 nm; (c) shows a single V2CT. x The SAED image of the superlattice and the corresponding TEM image shown in the inset of (c) show two identical sets of hexagonal diffraction spots with a twist angle of 2θ = 6.0°; (d) is the corresponding HRTEM image, showing a moiré periodic pattern with hexagonal unit cells (marked with orange hexagons); the inset is a V2CT based on a twist angle of 6.0°. x A moiré superlattice model constructed from atomic layers; (e) is V2CT xThe total density of states (DOS) spectrum of the superlattice shows the Fermi level (E). F The density of electronic states at () is enhanced; (F) represents V2CT. x Ultraviolet photoelectron spectroscopy (UPS) of superlattices, showing Fermi levels (E F It has a stronger electronic state density at )

[0082] Figure 3 For a single V2CT x Moiré patterns of superlattices; where (a) is a TEM image of a single MXene coiled structure with one sidewall exposed at the end (no top wall); (b) and (c) are the corresponding HRTEM images (b) and V2CT-based images. x A moiré superlattice model constructed from atomic layers (c) is shown in the image, revealing a moiré periodic pattern with a twist angle of 16°, similar to V2CT at the same twist angle. x The atomic layer-based Mohr superlattice model is highly consistent; (d) TEM image of a single MXene rolled-up structure, showing an overlapping region between its top and bottom walls; (e, f) corresponding HRTEM images (e) and V2CT-based images. x The moiré superlattice model (f) constructed from atomic layers shows the same moiré periodic pattern as the single-sidewall model, which clearly demonstrates that the MXene rolled structure has a moiré superlattice structure.

[0083] Figure 4 (af) represents different individual V2CTs. x SAED diagrams of superlattices, in which the measured torsion angles of each individual superlattice are: 2θ = 8.0° (a), 2θ = 12° (b), 2θ = 16° (c), 2θ = 20° (d), 2θ = 25° (e) and 2θ = 30° (f).

[0084] Figure 5 (a) represents V2CT x FTIR spectrum of the superlattice at 3425.0 cm⁻¹ -1 and 621.0cm -1 Two strong vibrational peaks appear at point A, corresponding to the vibrations of the -OH bond (gray area) and the VO bond (blue area), respectively; (b) is V2CT based on the same baseline. x Magnified spectra of the -OH vibrational peaks in superlattices and nanosheets to clearly identify peak shifts. (Compared to isolated V2CT) x Nanosheets (3434.6cm) -1 Compared to V2CT x The -OH vibration peak of the superlattice exhibits a redshift (3425.0 cm⁻¹). -1 This indicates the presence of hydrogen bonds in the superlattice. Furthermore, compared to isolated V2CT... x Nanosheets (594.0 cm)-1 Compared to V2CT x The VO vibration peak of the superlattice is at ~621.0 cm⁻¹. -1 The area exhibits a blue shift and an asymmetrical peak shape, which should be attributed to the bending strain present in the rolled-up superlattice.

[0085] Figure 6 In the middle (a, b), there is a single V2CT. x STEM image (a) and corresponding high-resolution STEM image (b) of the rolled-up structure show that the structure is an open-end rolled-up structure, with a start layer and a stop layer that can be identified, and the interlayer spacing is approximately 1.14 nm; (c, d) show a single V2CT. x STEM image (c) and element mapping image (d) of the rolled-up structure show that the four elements V, C, O and F are uniformly distributed in the structure.

[0086] Figure 7 In the equation (a, c, e, g, i, k), (Ti) represent (Ti) 0.5 V 0.5 )2AlC(a), (Nb 0.4 V 1.6 AlC(c), (Ta 0.4 V 1.6 AlC(e), Ti2Al(C) 0.5 N 0.5 (g) TiVAl(C) 0.5 N 0.5 (i), Ti3AlCN(k) and one-dimensional curls derived from these MAX phases

[0087] XRD patterns of MXene. All patterns show the characteristic (002) diffraction peaks unique to MXene; (b, d, f, h, j, l) represent (Ti) diffraction peaks. 0.5 V 0.5 )2CT x (b), (Nb) 0.4 V 1.6 CT x (d), (Ta 0.4 V 1.6 CT x (f) Ti2(C) 0.5 N 0.5 )T x (h), TiV(C) 0.5 N 0.5 )T x (j) Ti3CNT x (l) TEM image of a one-dimensional rolled MXene structure.

[0088] Figure 8 In the equation (a, c, e, g, i, k, m, o, q, s), Ti2AlC(a), Nb2AlC(c), Ti3AlC2(e), and V2Al(C) are respectively. 0.67 N 0.33 (g) V2Al(B) 0.28 C 0.57 N 0.15 (i), (V) 1.8 Sc 0.2 AlC(k), (V) 0.5 Cr 0.5 )2AlC(m), (V 1.8 Mn 0.2 AlC(o), (Ti 1.6 Nb 0.4 AlC(q), (Ti 1.6 Ta 0.4 XRD contrast maps of AlC(s) and one-dimensional curled MXene derived from these MAX phases; (b, d, f, h, j, l, n, p, r, t) represent Ti2CT. x (b) Nb2CT x (d) Ti3C2T x (f), V2(C) 0.67 N 0.33 )T x (h), V2(B) 0.28 C 0.57 N 0.15 )T x (j), (V) 1.8 Sc 0.2 CT x (l),(V 0.5 Cr 0.5 )2CT x (n), (V) 1.8 Mn 0.2 CT x (p), (Ti 1.6 Nb 0.4 CT x (r), (Ti 1.6 Ta 0.4 CT x (t) TEM image of one-dimensional curled MXene.

[0089] Figure 9 The middle (ad) represents a single Ti2CT. x (a) Nb2CT x (b), (Nb) 0.4 V 1.6 CT x (c), and (Ta0.4 V 1.6 CT x (d) SAED patterns of superlattices. The twist angles of these individual superlattices were determined to be 2θ = 20°, 2θ = 18°, 2θ = 15° and 2θ = 15°, respectively.

[0090] Figure 10 For M 2-n V n CT x Environmental stability of (M = titanium, niobium, tantalum) rolled thin films; where (ac) represents (Ti 0.5 V 0.5 )2CT x (a), (Nb) 0.5 V 0.5 )2CT x (b) (Ta 0.5 V 0.5 )2CT x (c) Photographs of rolled-up thin films prepared from corresponding aqueous dispersions exhibiting the Tyndall effect; (df) is a (Ti 0.5 V 0.5 )2CT x (d), (Nb) 0.5 V 0.5 )2CT x (e), (Ta 0.5 V 0.5 )2CT x (f) The XRD patterns of the rolled film after 0, 10 and 30 days of exposure to room temperature and dry air (relative humidity: 20%) show the same (002) diffraction peak as the original MXene film, indicating that the film still has good environmental stability after 30 days of exposure to dry air.

[0091] Figure 11 V2CT after different etching reaction times x Material characterization of MXene, where (a) represents vanadium dissolution (black Y-axis) and V2CT. x The graph shows the relationship between the bending stiffness (red Y-axis) of MXene and reaction time. The results indicate that as the reaction time increases from 4 h to 96 h, the vanadium dissolution rate increases, and V2CT... x The bending stiffness of MXene decreases. Clearly, the bending stiffness of the MXene layer is highly correlated with the vanadium vacancy concentration, and exhibits a negative correlation; (b, c) show the V2CT values ​​after reaction times of 4 to 96 hours. xThe vanadium K-edge X-ray absorption near-edge structure (XANES) spectrum (b) and electron paramagnetic resonance (EPR) spectrum (c) corresponding to MXene. A shift towards higher energies is observed in the 5473-5476 eV region of the vanadium K-edge XANES spectrum, indicating that V2CT increases with increasing reaction time. x The concentration of vanadium vacancies in MXene increases; (d) shows V2CT stripped in TBPH solution after reaction times of 4 to 96 h. x SEM images of MXene show a clear transformation in morphology from two-dimensional nanosheets to a one-dimensional rolled structure. This indicates that the low bending stiffness induced by vacancies is conducive to the formation of the one-dimensional rolled structure.

[0092] Figure 12 For M 2-n CT x The relationship between the theoretical bending stiffness and M vacancies of (M = vanadium, titanium, niobium, tantalum, n = 0-4 / 8) shows that as the proportion of M vacancies increases from 0 to 4 / 8, the bending stiffness decreases significantly with the increase of M vacancies in the MX layer.

[0093] Figure 13 (a) shows the surface tension of a 25 wt.% solution of TBPH, TBAOH, TMAOH, and water (H₂O). The surface tension of the TBPH solution is 32.2 mN / m. -1 The concentration is much lower than that of TBAOH solution (55.6 mN m). -1 ), TMAOH solution (65.9 mN m -1 ) and water (71.9mN m -1 (b) is TBP + TBA + TMA + Size of cations and H2O molecules, TBP + The size is Greater than TBA + TMA + and H2O (cf): Under the action of 25wt.% TBPH (c), TBAOH (d), TMAOH (e) and H2O (f) solutions, V2CT after peeling x SEM image.

[0094] Figure 14 For a single non-van der Waals superlattice (V2CT) x Electro- and magnetic transport properties of superlattices. Among them, (a) shows a single V2CT. xA schematic diagram of electrical measurements of a superlattice four-terminal device on a SiO2 / Si substrate, with platinum (Pt) electrodes fabricated on the device surface. (b) A single V2CT measured by the four-probe method. x The superlattice current-voltage curve shows typical ohmic characteristics, and the device has a current-voltage ratio of approximately 30,000 S cm⁻¹. -1 High electrical conductivity. The illustration shows a single V2CT. x Magnified SEM images of superlattice devices. (c) shows a single V2CT. x The resistivity-temperature dependence curves of the superlattice in the temperature range of 300 to 2K are shown in the inset, which is an enlarged resistivity-temperature plot of the superlattice; (d) is the magnetoresistance (ΔMR)-magnetic field dependence curve at 2K. The results show that a single V2CT x An unexpected positive linear magnetoresistance relationship exists in the superlattice.

[0095] Figure 15 V2CT x Random thin films and V2CT x Characterization of nanosheet thin films; where (a) is the result of V2CT. x SEM images of random thin films prepared by superlattice vacuum-assisted filtration show a large number of randomly distributed rolled structures within the film. The inset is an optical image of this random thin film; (b) is a V2CT image. x High-resolution cross-sectional SEM image of the random thin film, showing its close-packed morphology with a diameter of approximately 45 nm; inset is the corresponding cross-sectional HRTEM image; (c) is the image obtained by V2CT. x SEM images of the nanosheet-fabricated thin film prepared by vacuum-assisted filtration show that the film has flexible layered characteristics. The inset is an optical image of the nanosheet film; (d) is a V2CT image. x Cross-sectional SEM images of the nanosheet film show that it has a tightly stacked layered structure with a small number of pores.

[0096] Figure 16 V2CT x Characterization of high-concentration dispersions in superlattice structures; where (a) represents V2CT. x High concentration of superlattice crystals (~180 mg / mL) 1 (a) Optical image of the dispersion, which has good viscoelasticity and is suitable for extrusion printing; (b) V2CT x Polarized optical microscopy (POM) images of the superlattice high-concentration dispersion clearly show birefringence, indicating that the dispersion has unique liquid crystal behavior.

[0097] Figure 17 V2CT x High concentration of superlattice crystals (~180 mg / mL) -1Rheological properties of the dispersion; where (a) is the relationship between viscosity and shear stress as a function of shear rate, and the results show that V2CT x (a) High-concentration dispersions in superlattice exhibit good shear-thinning behavior; (b) is V2CT x The elastic modulus and viscous modulus of the superlattice high-concentration dispersion show that the dispersion has viscoelastic gel-like properties.

[0098] Figure 18 V2CT x Preparation and characterization of superlattice oriented thin films; wherein (a) is: preparation of V2CT by overextrusion under shear flow. x A schematic diagram of the superlattice-oriented thin film fabrication process; (b, c) are SEM images of the surface (b) and cross-section (c) of the oriented thin film, showing good orientation (marked by white arrows); the inset of Figure (b) is a TEM image of the oriented thin film; (d) is a three-dimensional atomic force microscope (3D AFM) image of the oriented thin film, showing an ordered structure and a flat surface with an average surface roughness (R0). a The wavelength is 16.9nm.

[0099] Figure 19 (a) is an optical image of a one-meter-long oriented thin film, showing good reflective properties; (b) and (c) are corresponding SEM images of the surface of the oriented thin film at different magnifications, showing an ordered array of MXene superlattices, indicating that the oriented thin film has good controllability and potential for large-scale production.

[0100] Figure 20 Characterization of the orientation of the thin film; where (a) is the wide-angle X-ray scattering (WAXS) pattern of the oriented thin film, which is obtained when the scattering vector (q) is One diffraction peak corresponds to V2CT x (a) is the (002) diffraction peak; (b) is the azimuth (φ) distribution diagram of the (002) peak of the oriented film, and the inset is a two-dimensional WAXS image, showing strong diffuse speckle in the equatorial direction. According to the formula Where f is the Hermann orientation factor. The azimuth angle of the (002) peak of the MXene thin film The average value of the square of the cosines was used to calculate the Hermann orientation factor (f), which was approximately 0.87, indicating that the oriented film has a high degree of orientation.

[0101] Figure 21 For non-van der Waals superlattices (V2CT) x Electromagnetic shielding effectiveness of a superlattice; where (a) represents the proposed electromagnetic shielding mechanism. The incident electromagnetic wave (black arrow) first irradiates the V2CT. x On the surface of a superlattice thin film, due to the high conductivity of V2CTx The superlattice contains abundant free electrons, and some electromagnetic waves are reflected (red arrows); the remaining electromagnetic waves are absorbed in the rolled-up structure after multi-angle scattering (blue arrows) and dipole polarization (gray arrows), and a small amount of electromagnetic waves are transmitted (orange arrows); (b) is a V2CT with a thickness of about 40 μm. x Electromagnetic shielding effectiveness (EMISE) of superlattice thin films in the X-band frequency range (8.2-12.4 GHz) was evaluated. The results showed that the shielding effectiveness of the sandwich film and the random film reached 124 dB and 119 dB, respectively, demonstrating significant shielding performance; (c) shows V2CT. x Total shielding effectiveness (SE) of superlattice thin films T ), absorption efficiency (SE) A ) and reflectivity (SE) R Data shows that V2CT x In superlattice sandwich films and random films, SE plays a dominant role. A Significant improvement; (d) V2CT with a thickness of 5 to 40 μm x SE of superlattice sandwich films T SE A and SE R The results showed that V2CT x The shielding effectiveness of superlattice sandwich films increases with increasing thickness; (e) represents V2CT. x A comparison of the specific shielding effectiveness-thickness ratio (SSE / t) of superlattice thin films with reported shielding materials shows that V2CT x The SSE / t of superlattice thin films is approximately 200,000 dB cm⁻¹. 2 g -1 It has excellent performance.

[0102] Figure 22 (a, b) are V2CT x Cross-sectional SEM images of the superlattice random thin film (a) and the oriented thin film (b) show that the thicknesses (t) of the random and oriented films are approximately 3 μm and 1 μm, respectively. For the random thin film, according to the formula (σ = 1 / (R... s ×t), combined with thickness and sheet resistance (R) s =0.32Ω□ -1 The calculated conductivity (σ) is approximately 10000 S / cm. -1 For oriented thin films, due to their orientation characteristics, the sheet resistance (R0) along the orientation direction and perpendicular to the orientation direction is... s There is a difference, which is 0.51Ω□ -1 and 2.51Ω□ -1Therefore, the corresponding conductivity along the orientation direction and perpendicular to the orientation direction are calculated to be approximately 20000 S cm⁻¹. -1 and 4000S cm -1 .

[0103] Figure 23 (a) represents V2CT x Optical images of superlattice thin films under bending deformation; (b) V2CT x Bending deformation cycle performance of superlattice thin films.

[0104] Figure 24 The electronic properties of the thermally treated MXene superlattice are shown; (a) is a schematic diagram of the hydrogen bond electron cloud, showing strong interfacial coupling; (b) is a schematic diagram of the thermally treated V2CT. x The current-voltage curve of the superlattice shows its conductivity (~4000 Scm). -1 (Lower than the original V2CT) x Superlattice (~30000S cm) -1 (c) is heat-treated V2CT x The Fourier transform infrared (FTIR) spectrum of the superlattice shows a blue shift in the hydroxyl (-OH) peak compared to the original superlattice, indicating that hydrogen bonds have been partially removed; (d, e) represent the heat-treated V2CT. x The ultraviolet photoelectron spectroscopy (UPS) (d) and total density of states (DOS) curves (e) of the superlattice show a decrease in electronic density of states compared to the original superlattice, indicating that the electronic coupling ability is significantly weakened after the partial removal of interlayer hydrogen bonds in MXene. This clearly demonstrates that hydrogen bonds in the superlattice can provide strong electronic coupling ability, thereby significantly improving the electrical conductivity of the material. Detailed Implementation

[0105] The technical solution of the present invention is illustrated below through specific embodiments. It should be understood that the one or more steps mentioned in the present invention do not preclude the existence of other methods and steps before or after the combined steps, or that other methods and steps may be inserted between these explicitly mentioned steps. It should also be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Unless otherwise stated, the numbering of each method step is only for the purpose of identifying each method step, and not for limiting the order of each method or limiting the scope of the present invention. Changes or adjustments to their relative relationships, without substantial changes to the technical content, can also be considered as within the scope of the present invention.

[0106] The raw materials and instruments used in the examples are not subject to any specific restrictions on their source; they can be purchased from the market or prepared according to conventional methods known to those skilled in the art.

[0107] Example 1: V2CT xPreparation and characterization of non-van der Waals superlattices

[0108] 1.1 V2AlC precursor and multi-slice V2CT x Preparation of MXene

[0109] First, V2AlC MAX phase precursors were synthesized using a powder sintering method. Vanadium powder, aluminum powder, and graphite powder were uniformly mixed in a molar ratio of 2.0:1.3:1.0 and sintered at 1500℃ for 4 hours under argon protection. The sintered bulk material was then ground and passed through a 400-mesh sieve to obtain V2AlC powder.

[0110] Subsequently, multilayer V2CTs were fabricated using in-situ HF etching. x Weigh 1.0 g of the above V2AlC powder and slowly add it to 20 mL of etching solution prepared by dissolving 1.0 g of NaF in 20 mL of 9M HCl solution. Transfer the mixture to a 50 mL high-pressure reactor lined with polytetrafluoroethylene and react at 95 °C for 96 hours. After the reaction, allow it to cool naturally to room temperature. Centrifuge repeatedly (3500 rpm, 5 min) and wash with deionized water until the pH of the supernatant is approximately 6. Dry the resulting precipitate in a vacuum drying oven at 60 °C for 6 hours to finally obtain multilayer V2CT. x MXene powder.

[0111] 1.2V2CT x Preparation of curled superlattices

[0112] Weigh 100 mg of the multilayer V2CT prepared above. x The powder was rapidly added to 10 mL of a 25 wt.% tetrabutylphosphine hydroxide (TBPH) aqueous solution under magnetic stirring (600 rpm). A black, multilayered V2CT was immediately observed. x The rapid expansion, peeling, and transformation into a dispersion with a silky sheen indicated the occurrence of rapid coiling. After continuous stirring for 30 minutes, the product was washed with deionized water by centrifugation until the supernatant was neutral to remove excess TBPH. Finally, the washed product was freeze-dried for 48 hours to obtain black V2CT. x Superlattice powder.

[0113] 1.3V2CT x Structural characterization of curled superlattices

[0114] Morphology and microstructure: Scanning electron microscope (SEM) images (as attached) Figure 2 As shown in Figure a), the obtained product consists of numerous one-dimensional fibrous structures, exhibiting good monodispersity and uniform diameter distribution. (Transmission electron microscopy (TEM) image) Figure 2Images b, 3a, and 3d further confirmed its one-dimensional coiled morphology. The diameter statistical distribution was mainly between 20 nm and 100 nm. The images clearly showed that the coiled structure was composed of a single atomic layer spirally wrapped together, with identifiable start and end edges, and a constant interlayer spacing between adjacent atomic layers, with a measured value of approximately 1.14 nm. Figure 5 a, b). The corresponding X-ray diffraction (XRD) pattern shows a strong and sharp (002) diffraction peak at approximately 7.8° (2θ) (not shown in the figure). According to the Bragg equation, the corresponding interlayer spacing d ≈ 1.13 nm is highly consistent with the HRTEM measurement results.

[0115] Crystal structure and periodicity: for a single V2CT x Selected area electron diffraction (SAED) analysis of the coiled structure (as shown in the attached diagram). Figure 2 (As shown in c and d). Two identical hexagonal diffraction lattices appear in the diffraction patterns, with a clear twist angle of 6.0° (2θ) between them. This indicates that the two atomic crystal layers are not simply stacked, but rather form a moiré superlattice structure with a specific rotation angle. It is noteworthy that not all moiré superlattices have a uniform twist angle; some variable twist angles ranging from 8° to 30° can be seen in the SAED pattern. Figure 4 ), similar to the reported disulfide curled superlattices.

[0116] Interface Chemistry and Hydrogen Bond Verification: Unlike typical van der Waals superlattices without dangling bonds, our V2CT x Mohr superlattices have abundant dangling bonds between layers, such as -OH and =O, which can be observed in Fourier transform infrared (FTIR) spectroscopy at 3425.0 cm⁻¹. -1 VO is at 621.0cm -1 This is confirmed by two strong vibrational peaks at that location. Figure 5 As shown, the spectrum is at 3425.0 cm⁻¹ -1 A strong and broad absorption peak was observed, attributed to the -OH stretching vibration in the structure. This is consistent with isolated V2CTs prepared by ultrasonic exfoliation. x Nanosheets (whose -OH peak is located at 3434.6 cm⁻¹) -1 In comparison, the -OH peak of the coiled superlattice prepared in this invention increased by approximately 9.6 cm⁻¹. -1 The redshift is a significant indicator of interlayer hydrogen bonding, suggesting strong interactions between adjacent MXene layers via -OH functional groups on their surfaces. Furthermore, at approximately 621.0 cm⁻¹... -1 The VO vibration peak at the location exhibits a blue shift and asymmetric broadening, which is attributed to the bending strain introduced by the rolled structure.

[0117] Elemental and Chemical State Analysis: Elemental Surface Maps under Scanning Transmission Electron Microscopy with Energy Dispersive X-ray Spectroscopy (STEM-EDS) (e.g.) Figure 6 (d) confirmed the uniform distribution of V, C, O, and F elements in a single coiled structure. X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge structure (XANES) spectroscopy (not shown) further indicated that, compared with the original multilayer V2CT... x In contrast, the increased vanadium valence in the coiled structure confirms the generation of transition metal (V) vacancies during etching and coiling.

[0118] Example 2: Preparation of MXene superlattices with different chemical compositions

[0119] This embodiment aims to demonstrate that the "stiffness-mediated curling" strategy described in this invention is a universal synthetic method applicable to the preparation of non-van der Waals superlattices from various transition metal carbides and carbonitrides.

[0120] 2.1 Preparation of different MXene superlattices

[0121] We selected various MAX phase precursors and etched and curled them according to a principle similar to that of Example 1, adjusting the etching conditions to suit the reactivity of different precursors. In all cases, a 25 wt.% TBPH solution was used as a stripping agent to trigger the curling process after the preparation of multilayer MXenes. The specific MXene superlattices and their precursors, as well as key preparation parameters, are shown in the table below:

[0122] Table 1. Summary of the preparation of different MXene superlattices

[0123]

[0124]

[0125] 2.2 Structural Characterization and Universality Verification

[0126] All the above products were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD) to confirm that they all successfully formed one-dimensional non-van der Waals superlattice structures, such as Figure 7 and 8 As shown, all prepared samples exhibited typical one-dimensional curled morphology, similar to the V2CT in Example 1. x Superlattices are similar. For example: (Ti 0.5 V 0.5 )2CT x ( Figure 7 b) and (Nb) 0.4 V 1.6 CT x ( Figure 7d) The uniform fibrous structure demonstrates the effectiveness of the solid solution strategy. Ti2(C) 0.5 N 0.5 )T x ( Figure 7 h), Ti3CNT x ( Figure 7 l), V2(B 0.28 C 0.57 N 0.15 )T x ( Figure 8 j) also successfully curled, indicating that this method is also applicable to carbon-nitrogen and carbon-nitrogen-boron compound systems. The XRD patterns of all products showed distinct and sharp (002) diffraction peaks in the low-angle region (~5°-10°), indicating the successful formation of layered stacked structures and large interlayer spacing, consistent with the model of interlayer embedding of TBPH molecules and formation of hydrogen bonds in curled structures. Selected area electron diffraction (SAED) patterns showed that these individual superlattices exhibited significant twist angles (j) Figure 9 ).

[0127] It is evident that, despite differences in chemical composition and precursor etching conditions, the stiffness-controlled curling strategy mediated by this invention can efficiently and reliably yield superlattices with one-dimensional curled morphology and ordered layered structures. This fully demonstrates the high universality of the method of this invention and lays the foundation for constructing a non-van der Waals superlattice material platform with variable composition and crystal structure.

[0128] 2.3 Stability Test

[0129] Observations of the storage of aqueous dispersions of these one-dimensional non-van der Waals superlattice materials revealed that they remained stable on the first day (color and crystal structure unchanged), but significant degradation (color change, XRD spikes) began to appear from the second day, indicating that they are not suitable for long-term storage in aqueous solutions. However, when these rolled structures were formed into dry films and stored in low-humidity air (20% RH), they exhibited excellent environmental stability. During a test period of up to 30 days, their macroscopic morphology and microscopic crystal structure (XRD patterns) did not show significant changes. Figure 10 It is evident that this type of material exhibits excellent long-term stability in dry environments, which is crucial for its application in practical devices such as electromagnetic shielding films and flexible electrodes.

[0130] Example 3: Verification of the relationship between bending stiffness control and curling behavior

[0131] This embodiment introduces vacancies of different concentrations by controlling the etching degree, and systematically studies the decisive influence of atomic layer bending stiffness (D) on its final morphology (two-dimensional nanosheets or one-dimensional curls), thereby verifying the correctness of the core mechanism of the present invention.

[0132] 3.1 Effect of vacancy concentration on bending stiffness

[0133] Using the V2AlC MAX phase as a model precursor, a series of multilayer V2CTs with different vanadium (V) vacancy concentrations were prepared by controlling the reaction time of in-situ HF (HCl / NaF) etching. x sample.

[0134] The experimental procedure included setting four different etching time points: 4 hours, 24 hours, 48 ​​hours, and 96 hours, while maintaining a constant etching temperature (95℃) and etchant concentration. After the reaction, the material was washed and dried according to standard procedures to obtain the corresponding multilayer V2CT. x .

[0135] The dissolved V content in the etching solution was analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES) to semi-quantitatively characterize the V vacancy concentration in different samples. The results showed that the V vacancy concentration increased significantly with etching time increasing from 4 hours to 96 hours. Based on density functional theory (DFT), we calculated V2CT with different V vacancy concentrations. x Bending stiffness (D) of a single-layer model. The calculation results show that the theoretical bending stiffness of the material is negatively correlated with the V-vacancy concentration; that is, the more vacancyes, the lower the bending stiffness. Figure 11 a).

[0136] 3.2 The decisive role of bending stiffness in the final morphology

[0137] Multilayer V2CT obtained at the above different etching times x Under identical conditions (using 25 wt.% TBPH solution), the samples underwent peeling and curling treatments, and their final morphology was observed. Figure 11 As shown in the SEM images of d, the morphology of the final product strongly depends on the etching degree (i.e., bending stiffness) of the precursor: After etching for 4 hours, the resulting material largely retains a two-dimensional nanosheet morphology, with only a very small amount of curling observed. At this point, the vacancy concentration is low, the bending stiffness is high, and the atomic layers have a strong resistance to bending deformation, making curling difficult. After etching for 24 hours, a partially curled morphology appears, meaning that the sample contains both flat nanosheets and initially curled structures. This indicates that the bending stiffness has decreased to near the critical point for curling. After etching for 48 hours and 96 hours, the sample almost completely transforms into a uniform one-dimensional curled structure. This shows that when the bending stiffness of the atomic layers is reduced to a critical value (D) through sufficient etching, the morphology of the final product is significantly improved. m When the peeling force provided by TBPH is below a certain level, it is sufficient to trigger rapid, thorough and orderly curling. Figure 12The relationship between the bending stiffness and M-vacancy for other types of MXene is presented, showing that the bending stiffness decreases significantly with the increase of M-vacancy in the MX layer. This further illustrates that the bending stiffness of atomic layers can be effectively customized by introducing vacancies. The "stiffness-mediated curling strategy" of this invention is a key mechanism for realizing the controllable transformation from two-dimensional nanosheets to one-dimensional superlattices.

[0138] 3.3 Theoretical Analysis

[0139] To achieve controllable and efficient fabrication of non-van der Waals superlattices of carbides and carbonitrides, this invention uses theoretical calculations to predict the ability of different MXene materials to form stable rolled structures. The stability of the rolled structure is determined by the total formation energy; when the formation energy reaches equilibrium (E... f When (=0), the coiled structure is in a stable state. In this state, the inner radius (R) of the coiled structure is... in The bending stiffness (D), interlayer binding energy (γ), and interlayer spacing (h) of the atomic layers satisfy certain numerical relationships (e.g., Figure 1 (as shown in b). Table 1 lists the key parameters and minimum inner radius R calculated for various typical MXene materials based on the above ideal curling model. m These parameters provide a theoretical basis for screening MXene materials suitable for forming non-van der Waals superlattices.

[0140] Table 2. Calculated binding energy (γ) and minimum inner radius (R) of MXene coiled structures m (Minimum number of rotations N = 1)

[0141]

[0142] As shown in Table 2, for M2XT x Type MXene (such as Ti2CT) x V2CT x The calculated minimum inner radius R m The relatively small wavelength (5.1 nm to 6.4 nm) indicates that this type of material is thermodynamically more prone to curling to form a superlattice structure. This makes V2CT the preferred material for this invention. x These materials, as model precursors, provide direct theoretical guidance.

[0143] To further improve the accuracy of theoretical predictions and make them closer to the actual preparation process, this invention further considers the influence of interlayer friction in MXene. The work done by friction (W) is introduced into the total formation energy. F After making corrections, the corrected equilibrium equations were derived, and the corrected minimum inner radius (R) was calculated accordingly. in Table 3 shows the friction coefficients and corrected inner radii of several key MXenes at a given width (B = 1 μm).

[0144] Table 3. Friction coefficient and modified inner radius (R) of different MXene coiled structures in (B = 1 μm)

[0145]

[0146] Example 4: Screening of key parameters for stripping agents

[0147] This embodiment aims to investigate the influence of the physicochemical properties of the stripper on its ability to trigger MXene curling behavior. The study compares the effects of different strippers on the same batch of multilayer V2CT. x The effect at that time was to identify the key parameters required for successful induction of curl.

[0148] 4.1 Experimental Design and Parameter Measurement

[0149] Four representative media were selected for treatment experiments, including: (1) Tetrabutylphosphine hydroxide (TBPH): the preferred stripping agent of this invention. (2) Tetrabutylammonium hydroxide (TBAOH): a commonly used quaternary ammonium base stripping agent. (3) Tetramethylammonium hydroxide (TMAOH): another quaternary ammonium base stripping agent with a smaller molecular size. (4) Deionized water: as a control.

[0150] Key physical parameters were measured for the above-mentioned 25 wt.% aqueous solutions. The surface tensions of TBPH, TBAOH, TMAOH, and H2O solutions were 32.2, 55.6, 65.9, and 71.9 mN m, respectively. -1 (See appendix) Figure 13 a) The hydrodynamic diameter of its hydrated ions was calculated using molecular dynamics simulations. TBP + TBA + TMA + The molecular size measurements of cations and H2O are respectively and ( Figure 13 b). Measurement was performed using the hanging plate method.

[0151] 4.2 Comparison of peeling and curling effects

[0152] Equal amounts of the same batch of multilayer V2CT x The powders were added to the four media mentioned above and observed and processed under the same conditions (room temperature, magnetic stirring). TBPH: multilayer V2CT was observed using an in-situ optical microscope. xRapid expansion, peeling, and transformation into a uniform black dispersion occurred within 0.3 seconds, indicating rapid and complete curling. TBAOH: The peeling process was slow, taking approximately 14.0 seconds, with the final product being a mixture of partially curled and partially nanosheet-like structures. TMAOH: The peeling speed was even slower (approximately 20.3 seconds), and the final product was primarily two-dimensional nanosheets with almost no observed curled structure. H2O: No significant peeling or curling behavior was observed; the material remained in a multilayered stacked state throughout.

[0153] The processed and dried product was observed using SEM. Figure 13 (cf) further confirms the above observations: the TBPH-treated product has a uniform one-dimensional coiled structure. The TBAOH-treated product has an incompletely coiled morphology, that is, partial coiling coexists with two-dimensional nanosheets. The TMAOH-treated product is almost entirely two-dimensional nanosheets. The H2O-treated product still retains the original multilayered stacked block morphology.

[0154] This embodiment clearly demonstrates through comparative experiments that the ability of the stripping agent to trigger MXene curling is closely related to its molecular size and surface tension. Large molecular size This helps generate sufficient steric hindrance and intercalation force between layers, overcoming interlayer interactions and providing initial curvature for curling. Low surface tension (≤40 mN / m). -1 The ability of the solution to rapidly wet and penetrate the interlayer of MXene is a key kinetic factor for achieving rapid exfoliation and deformation. Only exfoliating agents (such as TBPH) that simultaneously meet the two key parameters of large molecular size and low surface tension can efficiently and completely induce the exfoliation and curling of multilayer MXene to form a one-dimensional superlattice. This provides a clear experimental basis and parameter range definition for the selection of exfoliating agents in this invention.

[0155] Example 5: Electrical and magnetic properties of a single superlattice

[0156] This embodiment utilizes micro-nano fabrication technology to prepare a single V2CT-based fabrication unit. x Superlattice devices are used to directly measure their intrinsic conductivity, carrier concentration, and mobility, and to study their magnetic transport behavior at low temperatures in order to reveal their unique electronic properties.

[0157] 5.1 Fabrication of Single Superlattice Devices

[0158] The preparation steps include: using the V2CT prepared in Case 1 x Superlattice powder was dispersed in anhydrous ethanol and briefly sonicated to form a homogeneous suspension. The suspension was drop-coated onto a silicon wafer covered with a 300 nm thick silicon dioxide insulating layer. After the ethanol evaporated, the superlattice was randomly distributed on the substrate. Device fabrication was performed using a focused ion beam system, selecting a well-formed and isolated V2CT. xSuperlattices as channel materials (e.g.) Figure 14 (As shown in a and b). Platinum (Pt) electrodes are deposited at both ends of the superlattice using ion beam-induced deposition technology to form a standard four-terminal measurement structure, thereby eliminating the influence of contact resistance.

[0159] 5.2 Electrical Performance Testing

[0160] Current-voltage characteristics: Measured at room temperature using a semiconductor parameter analyzer. For example... Figure 14 As shown in b, the measured IV curves exhibit a perfect linear relationship, indicating that the Pt electrode and V2CT... x Ohmic contacts are formed between the superlattices, ensuring the accuracy of subsequent measurements.

[0161] Conductivity calculation: Based on the resistance values ​​measured by the four-terminal method, and considering the cylindrical geometry of the superlattice (its diameter and spacing between adjacent electrodes were determined by SEM images), as shown in Table 4, the conductivity of a single V2CT was calculated. x The electrical conductivity of superlattices is as high as approximately 30,000 S cm⁻¹ -1 In contrast, single-layer V2CT prepared using the same method... x Nanosheet devices with a conductivity of only about 1,311 S cm⁻¹ -1 (like Figure 14 (b is shown in the comparison). The superlattice conductivity of the present invention is increased by approximately 22 times.

[0162] Table 4. Single V2CT x Electrical test results of superlattices

[0163]

[0164] 5.3 Hall Effect Test

[0165] To investigate the physical reasons for the significant increase in conductivity, we performed Hall effect measurements on devices based on superlattice thin films. The testing method included measuring the Hall coefficient (RH) under a vertical magnetic field of 0.35 T. H According to the formula:

[0166] n H =1 / (eR) H )μ H =σR H

[0167] Where, n H Hall carrier concentration, R H Hall coefficient, μ H Hall mobility, e: electron charge (physical constant, approximately 1.602 × 10⁻⁶) -19Coulomb), σ: conductivity, and here it is specified that the measurement method is "four-probe electrical measurement" to ensure data traceability.

[0168] V2CT was calculated x The Hall carrier concentration of the superlattice thin film is as high as 2.9 × 10⁻⁶. 22 cm -3 (Table 5). This value is higher than V2CT. x Nanosheet thin films (~10 20 cm -3 This is two orders of magnitude higher. Combined with conductivity data, the calculated carrier mobility is approximately 2.2 cm⁻¹. 2 V -1 s -1 This indicates that the ultra-high conductivity mainly originates from the abnormally high carrier concentration in the superlattice, which is consistent with the theoretically calculated results of a significantly enhanced density of electronic states (DOS) at the Fermi level.

[0169] Table 5. Hall Effect Measurement

[0170]

[0171] 5.4 Magnetoresistive Behavior Test

[0172] A single superlattice device was placed in a cryostat (temperature can be reduced to 2K) and a superconducting magnet (magnetic field up to 9T) to measure its magnetoresistance (ΔMR) behavior. For example... Figure 14 As shown in d, at a low temperature of 2K, when the applied magnetic field is scanned from 0T to 5T, V2CT... x The resistance of a superlattice increases linearly with increasing magnetic field, exhibiting a clear positive linear magnetoresistance effect. This contrasts sharply with conventional V2CT. x Nanosheets exhibit common negative magnetoresistance behavior under the same conditions, which is usually attributed to weak localization effects.

[0173] This embodiment verifies the V2CT fabricated by the present invention through precise measurements of a single superlattice device. x Non-van der Waals superlattices possess unique properties, including: exceptional electrical conductivity (~30,000 S cm⁻¹). -1 ), far exceeding its two-dimensional nanosheet morphology; extremely high carrier concentration (~10 22 cm -3 This forms the structural basis for achieving high electrical conductivity. The novel positive linear magnetoresistance effect, distinct from the conventional negative magnetoresistance behavior of most MXene materials, suggests the possible existence of a unique electron scattering or band structure mechanism within it. These superior electrical and magnetic properties make this material a promising candidate for applications in next-generation nanoelectronic devices, high-performance sensors, and spintronics.

[0174] Example 6: Electromagnetic Interference Shielding Performance

[0175] This embodiment systematically evaluated and compared the electromagnetic interference shielding effectiveness in the X-band (8.2-12.4 GHz) by preparing three superlattice thin films with different structures, demonstrating their great potential as a next-generation high-performance shielding material.

[0176] 6.1 Thin Film Preparation

[0177] (1) Random film: The V2CT prepared in Example 1 will be used as a random film. x The superlattice is dispersed in water to form a uniform dispersion (~15 mg / mL). -1 The dispersion was filtered onto a microporous membrane using vacuum-assisted filtration technology to form a self-supporting film. The film was then peeled off the membrane to obtain a random film containing a superlattice with random distribution. Figure 15 (SEM images of a and b). The film thickness was precisely controlled between 5 and 40 μm by controlling the volume of the dispersion liquid.

[0178] (2) Orientation film: High concentration of V2CT was prepared by referring to the method in Example 1. x Superlattice dispersion (~180 mg / mL) -1 The dispersion exhibits obvious liquid crystal behavior. Figure 16 The polarized microscope image of b shows birefringent texture and shear thinning behavior. Figure 17 Subsequently, the high-viscosity dispersion was loaded into an injection pump and extruded onto the substrate through a flat needle (slit width ~500μm). Figure 16 a). During extrusion, shear force causes the one-dimensional superlattice to be highly oriented along the extrusion direction ( Figure 18 b, c, Figure 19 After drying, an oriented thin film is obtained. Wide-angle X-ray scattering (WAXS) measurements show that its Hermann orientation factor is as high as 0.87. Figure 20 This confirms the high degree of orientation.

[0179] (3) Sandwich film: In order to balance isotropic shielding and high conductivity, we designed and fabricated a sandwich sandwich structure film. First, a random film was prepared as the bottom layer, and then a thin oriented film was prepared on its surface by extrusion technology as the middle layer. Finally, another random film was covered on the oriented layer by vacuum filtration as the top layer, thus forming a sandwich structure of "random layer / oriented layer / random layer".

[0180] 6.2 Performance Testing and Comparative Analysis

[0181] The conductivity and electromagnetic interference shielding effectiveness of all thin films were tested.

[0182] (1) Conductivity: The conductivity of the random thin film is approximately 11,000 S cm⁻¹. -1 The conductivity of the oriented thin film along the orientation direction is increased to approximately 20,000 S cm⁻¹. -1 This demonstrates the benefit of orientation alignment for electron transport. The conductivity of the sandwich film is comparable to that of the random film (see Table 6). Figure 22 ).

[0183] Table 6. V2CT x Electrical test results of thin films

[0184]

[0185] (2) Electromagnetic Interference Shielding Effectiveness: The total shielding effectiveness (SE) of the thin film was measured using a vector network analyzer in the X-band (8.2-12.4 GHz). T ), reflectivity (SE) R ) and absorption efficiency (SE) A For a 40 μm thick film, the SE of a random film T The average value is as high as 119 dB, while the SE of the sandwich film is... T The peak reached a record 124 dB. Figure 21 b). This means that the energy of the incident electromagnetic wave is attenuated to 10% of its original value. -12 Only a very small amount of transmission occurs. In contrast, at the same thickness, V2CT... x Thin films prepared from nanosheets have a high SE T Only 60dB Figure 21 c). The performance of the superlattice thin film of the present invention is more than doubled.

[0186] By analyzing SE A and SE R ( Figure 21 d) It was found that the shielding mechanism of superlattice thin films is dominated by absorption (SE). A >97dB), rather than reflection. This is due to the ohmic loss caused by its high conductivity, the multiple internal reflections and scattering caused by the one-dimensional coiled structure, and the dipole polarization relaxation caused by the hydrogen bond interface, which together lead to the efficient dissipation of electromagnetic wave energy.

[0187] To fairly compare the shielding efficiency of materials with different thicknesses and densities, we calculated the absolute shielding effectiveness. The SSE / t value of the superlattice thin film of this invention can reach ~200,000 dB cm⁻¹. 2 g -1 ( Figure 21 e. Table 7) shows that the efficiency is far greater than that of nanosheet films (~20,000 dB cm⁻¹). 2 g -1 ) and traditional metallic shielding materials such as copper foil (~8,000 dB cm⁻¹)2 g -1 ).

[0188] Table 7. V2CT x Absolute specific shielding effectiveness (SSE / t) of superlattice thin films

[0189]

[0190] (3) Mechanical flexibility: V2CT x Bending performance tests on the superlattice random thin film showed that it could withstand 20,000 bending deformation cycles at a deformation distance of 4 mm, comparable to V2CT. x The nanosheet film (21,000 cycles) exhibits comparable performance and demonstrates excellent mechanical flexibility. Figure 23 ).

[0191] This embodiment fully demonstrates that the one-dimensional non-van der Waals superlattice material of the present invention can be fabricated into various forms of products, such as self-supporting thin films, coatings, foams, or bulk composite materials, exhibiting excellent electromagnetic interference shielding performance. In particular, its total shielding effectiveness of 124 dB and ~200,000 dB cm⁻¹ shielding efficiency are particularly noteworthy. 2 g -1 Its absolute shielding effectiveness is among the highest of its kind. Its absorption-dominated shielding mechanism also better meets the green shielding requirements of modern electronic devices for low electromagnetic reflection. These superior properties give it extremely broad application prospects in high-end fields such as aerospace, flexible electronics, and defense.

[0192] Comparative Example 1: Superlattice after heat treatment (verification of hydrogen bonding)

[0193] This comparative example demonstrates the core role of strong hydrogen bond coupling by selectively disrupting the interlayer hydrogen bond network of the superlattice material prepared in this invention through heat treatment, and systematically studying the effect of this process on its structure and electrical properties.

[0194] D1.1 Heat Treatment Process

[0195] The V2CT prepared in Example 1 x The superlattice powder was placed in a vacuum tube furnace. Under argon protection, it was heated to 350°C at a heating rate of 5°C / min and held at this temperature for 2 hours. Subsequently, the sample was allowed to cool naturally to room temperature within the furnace. This heat treatment temperature was intentionally chosen to partially remove the hydrophilic -OH functional groups on the MXene surface, thereby weakening interlayer hydrogen bonds, while avoiding drastic phase transitions or oxidation of the material.

[0196] D1.2 Characterization of Structural and Chemical Changes

[0197] The heat-treated sample was subjected to FTIR testing and compared with the original superlattice. Figure 24 (a, c) It can be observed that after heat treatment, the temperature is located at ~3425 cm⁻¹. -1 The intensity of the -OH stretching vibration peak at the surface was significantly reduced, and the peak position shifted slightly to higher wavenumbers (blue shift). This indicates that the heat treatment process did indeed lead to a reduction in the number of -OH functional groups on the material surface and a weakening of the hydrogen bond interaction strength of the remaining -OH groups.

[0198] D1.3 Electrical and Electronic Performance Degradation

[0199] The electrical conductivity decreased significantly: A single-element device based on a heat-treated superlattice was fabricated and measured using the same method as in Example 5. Its conductivity dropped sharply to approximately 4,000 S cm⁻¹. -1 ( Figure 24 b). This is approximately 30,000 Scm from the original superlattice. -1 The difference in conductivity is orders of magnitude, clearly demonstrating the catastrophic impact of weakened hydrogen bonds on conductivity.

[0200] Decreased electronic state density: Ultraviolet photoelectron spectroscopy (UPS) was used to test the samples before and after heat treatment. Figure 24 d, e). The results show that the heat-treated sample reaches the Fermi level (E). F The density of electronic states near the Fermi level decreases significantly. This result is in complete agreement with the trend predicted by density functional theory (DFT) calculations: when hydrogen bonds are broken, interlayer electronic coupling weakens, leading to a reduction in the number of electronic states available for conduction at the Fermi level.

[0201] It is evident that the strong interlayer electron coupling mediated by hydrogen bonds in the superlattice of this invention is the reason for its ultra-high electrical conductivity (~30,000 Scm). -1 The fundamental reason is not simply the material composition or macroscopic morphology.

[0202] Example 7: Preparation and System of Oriented Thin Films without Van der Waals Superlattices

[0203] This embodiment aims to illustrate how to use the system described in this invention, specifically the V2CT in Embodiment 1. x Thin films with high orientation were prepared using non-van der Waals superlattices (one-dimensional nanomaterials) as raw materials. The steps included:

[0204] Raw material preparation: V2CT preparation x A high-concentration aqueous dispersion of a non-van der Waals superlattice (one-dimensional rolled structure). Specifically, 1g of multilayer V2CT... xAdd 10 mL of 25 wt.% TBPH solution to the mixture with magnetic stirring (600 rpm) for 30 minutes. After the reaction, wash repeatedly with deionized water until neutral, centrifuge at 11000 rpm for 15 minutes, and collect the precipitate. Redisperse the precipitate in 5 mL of deionized water by mechanical stirring to obtain a concentration of approximately 180 mg / mL. 1 A viscoelastic dispersion with liquid crystal properties.

[0205] System Configuration and Loading: An extrusion printing system is used, which mainly includes: a 3mL syringe as a storage unit; a flat needle with an inner diameter of 500μm as an extrusion unit, which is fixed on a three-axis moving platform (control unit, such as the Fisnar F4200n desktop robot); and a heating plate as a forming unit (substrate). The high-concentration dispersion prepared in step 1 is loaded into the syringe, and the flat needle is installed, ensuring that the system is sealed and leak-free.

[0206] Orientation film preparation (printing process): The printing parameters are set through the control unit: extrusion pressure is 150 kPa, printing platform temperature is 80℃, and printing speed is 10 mm / s. -1 The system is started, and the control unit drives the extrusion unit to extrude the liquid crystal dispersion at a constant rate through a flat needle. Under shear force, V2CT in the dispersion... x One-dimensional superlattices are arranged in a highly ordered manner along the extrusion direction. The extruded strip material is dried instantly on a heating plate (forming unit) at 80°C, solidifying to form a self-supporting film.

[0207] Post-processing: The obtained film was dried under vacuum at 80°C for 4 hours to obtain the final V2CT. x Non-van der Waals superlattice oriented thin films.

[0208] The system of this invention can successfully and efficiently process one-dimensional non-van der Waals superlattice dispersions into self-supporting films with high orientation and high conductivity.

[0209] Example 8: Preparation and System of Large-Scale Meter-Scale Oriented Thin Films

[0210] This embodiment aims to demonstrate the capability of the system described in this invention for large-scale, continuous production of one-dimensional nanomaterial oriented thin films. The steps include: using the same raw materials and system configuration as in Example 7; programming in the control unit to cause a three-axis moving platform to drive the extrusion unit in a continuous reciprocating path motion, thereby printing a continuous film with an area of ​​one meter by ten centimeters on a heating plate. The printing parameters are similar to those in Example 7, and by optimizing path planning and extrusion speed, the continuity and uniformity of material extrusion over the entire large area are ensured.

[0211] Example 9: Preparation and System of Sandwich Structure Electromagnetic Shielding Thin Film

[0212] This embodiment aims to illustrate that the system of the present invention can not only prepare single-oriented thin films, but also achieve the controllable construction of complex structure thin films by integrating traditional processes (such as vacuum filtration) and printing technology, thereby meeting specific high-performance application requirements. The steps include: First, vacuum-assisted filtration V2CT... x Superlattice dispersion (approximately 15 mg / mL) -1 A randomly oriented thin film (random layer) of approximately 20 μm thickness was prepared on the filter membrane. The filter membrane with the random layer was placed on the heating plate (forming unit) of the printing system. Following the method of Example 7, a V2CT layer was directly printed on the surface of the random layer. x The orientation layer of the superlattice. Using the aforementioned composite structure with random / oriented layers as a new filter, V2CT is filtered again with vacuum assistance. x Suspension (approximately 15 mg / mL) 1 A random layer of approximately 20 μm thickness was constructed on top of the oriented layer. The resulting "random layer / oriented layer / random layer" sandwich structure was then peeled off from the filter membrane and thoroughly dried in a vacuum drying oven at 80 °C.

[0213] Example 10: Multiple Applications and Uses

[0214] This embodiment provides various applications of one-dimensional non-van der Waals superlattice materials, including:

[0215] (1) Functional coating

[0216] The one-dimensional non-van der Waals superlattice material dispersion of the present invention (e.g., concentration of 1-50 mg / mL) -1 It is applied to the surface of various substrates (such as polymers, glass, metals, or textiles) by spraying, spin coating, or blade coating, and forms a strong conductive coating after drying. The one-dimensional coiled structure can overlap better, forming an effective conductive path even under low load. Compared with two-dimensional sheets, its coating is less prone to cracking and has stronger adhesion. It can be used to prepare antistatic coatings, transparent conductive films, electrothermal de-icing / defogging coatings, and electromagnetic shielding fabrics, etc.

[0217] (2) Three-dimensional porous foam

[0218] Directional freeze-drying technology is employed. The one-dimensional non-van der Waals superlattice material aqueous dispersion of this invention is injected into a mold and frozen in a specific direction under controlled low-temperature conditions. During this process, ice crystal growth repels and confines the one-dimensional superlattice within the gaps in the ice crystals, forming a directional pore wall structure. Subsequently, the ice crystals are removed by freeze-drying, yielding a three-dimensional foam with a directional porous structure. This foam possesses a highly interconnected porous network, with a porosity exceeding 99% and an extremely low density (<10 mg / cm³). -3 The one-dimensional coiled structure endows the foam with excellent resilience, allowing it to withstand significant compressive deformation and fully recover. Simultaneously, its conductive network remains stable under repeated deformation, achieving a conductivity of ~1 S cm⁻¹. -1 It can be used as a high-performance piezoresistive sensor, a high-efficiency oil-water separation material, or a lightweight broadband absorbing material.

[0219] (3) Polymer matrix composites

[0220] Composite materials are prepared by solution blending or melt blending of the one-dimensional non-van der Waals superlattice material powder of the present invention as a filler with a polymer matrix (such as epoxy resin, polydimethylsiloxane PDMS, polyvinyl alcohol PVA). The one-dimensional coiled structure effectively prevents its own surface stacking and is easier to disperse in the matrix. Its abundant functional groups (-OH, =O) on its surface can form strong interfacial interactions with the polymer molecular chains. In terms of performance improvement, a conductive percolation network can be formed even at extremely low filler content (e.g., 0.5 wt.%), transforming the insulating polymer into a conductor. The one-dimensional structure, as a nano-reinforcement, can effectively transfer stress, significantly improving the strength, modulus, and toughness of the composite material. The composite material simultaneously possesses the flexibility / processability of the matrix and the electrical / thermal functions of the superlattice. It can be used to manufacture electromagnetic interference resistant electronic packaging shells, high-strength, lightweight structural-functional integrated aerospace materials, and wear-resistant, conductive tires or conveyor belts, etc.

[0221] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A one-dimensional non-van der Waals superlattice material, characterized in that, It is formed by at least one two-dimensional material atomic layer helical curling, and adjacent layers of the atomic layer are coupled by hydrogen bonds.

2. The one-dimensional non-van der Waals superlattice material of claim 1, wherein, The two-dimensional material is a transition metal carbide, carbonitride or a combination thereof; Or, the two-dimensional material is MXene.

3. The one-dimensional non-van der Waals superlattice material of claim 2, wherein, The general formula of the MXene is M n+ 1X n T x wherein M is at least one transition metal, X is at least one of carbon, nitrogen or boron, T x represents a contained surface functional group, 1≤n≤3; Preferably, the MXene has the general formula M2XT x , M3X2T x or M4X3T x ; More preferably, the general formula of the MXene is (M 2-m M” m )XT x wherein m is a non-zero real number between 0 and 2, M' and M" are two different transition metals; More preferably, the transition metal is selected from at least one or two of vanadium (V), titanium (Ti), niobium (Nb), tantalum (Ta), scandium (Sc), manganese (Mn), chromium (Cr), molybdenum (Mo), tungsten (W), zirconium (Zr), hafnium (Hf).

4. The one-dimensional non-van der Waals superlattice material of any one of claims 1 to 3, wherein, The interlayer spacing between adjacent atomic layers is 0.8 nm to 2.0 nm; preferably, the interlayer spacing is 1.10 nm to 1.20 nm; And / or, the inner radius of the one-dimensional non-van der Waals superlattice material is between 5 nm and 100 nm; preferably, the inner radius is between 10 nm and 50 nm; And / or, the aspect ratio of the one-dimensional non-van der Waals superlattice material is between 5 and 100.

5. The one-dimensional non-van der Waals superlattice material of any one of claims 1 to 4, wherein, The material has a moire superlattice structure; preferably, the moire superlattice structure has an interlayer twist angle of between 2° and 30°; and / or, the hydrogen bond coupling is confirmed by a red shift of the -O-H bond vibration peak in a Fourier transform infrared spectrum; preferably, the -O-H bond vibration peak is located in the wave number range of 3420 cm -1 to 3430 cm -1 .

6. The one-dimensional non-van der Waals superlattice material of any one of claims 1 to 5, wherein, The electrical conductivity of the material is not less than 10,000 S cm at a temperature of 300 K -1 ; preferably, the electrical conductivity is not less than 20,000 S cm -1 ; more preferably, not less than 30,000 S cm -1 ; and / or the charge carrier concentration of the material is not less than 1 x 1016cm-3 21 cm -3 ; And / or, the material exhibits a positive linear magnetoresistance effect.

7. A method of making a one-dimensional non-van der Waals superlattice material as claimed in any one of claims 1 to 6, characterised in that, The method comprises the following steps: a) providing a multi-layer two-dimensional material; b) treating the multi-layer two-dimensional material to reduce the bending stiffness of its atomic layers; c) contacting the treated multi-layer two-dimensional material with a peeling agent, thereby causing the atomic layers to peel off and curl, forming a one-dimensional non-van der Waals superlattice structure.

8. The method of claim 7, wherein, The step of "treating the multi-layer two-dimensional material to reduce the bending stiffness of its atomic layers" is achieved by introducing vacancies in the atomic layers; preferably, the vacancies are transition metal vacancies.

9. The method of claim 8, wherein, The vacancies are introduced by a chemical etching method; preferably, the chemical etching method uses an etchant containing fluoride; more preferably, the etchant is a mixed solution of hydrochloric acid and fluoride salt, or a hydrofluoric acid solution; And / or, the reaction temperature of the chemical etching is room temperature to 95°C, and the reaction time is 4 to 96 hours.

10. The method of claim 8, wherein, The vacancies are introduced by using a precursor material with vacancy or solid solution structure; Preferably, the precursor is a MAX phase having a general chemical formula of M n+1 AX n wherein M is at least one transition metal, A is a group 13-16 element, X is at least one of carbon, nitrogen, boron, 1n3; and vacancies exist at the M sites or a solid solution is formed by at least two transition metals; More preferably, the general formula of the MAX phase is M2AX, M3AX2 or M4AX3; More preferably, the MAX phase is (M 2-m M" m )AX, where m is a non-zero real number between 0 and 2, M' and M" are two different transition metals; Again more preferably, the transition metal is selected from at least one or two of vanadium (V), titanium (Ti), niobium (Nb), tantalum (Ta), scandium (Sc), manganese (Mn), chromium (Cr), molybdenum (Mo), tungsten (W), zirconium (Zr), hafnium (Hf).

11. The method of any one of claims 7 to 10, wherein, The release agent is a compound having a macromolecular size and a low surface tension; the molecular size of the release agent is not less than 1,000,000 g / mol More preferably, not less than 2,000,000 g / mol The surface tension of the compound is ≤ 40 mN / m -1 More preferably, ≤ 35 mN / m -1 ; And / or, the peeling agent is a quaternary phosphonium base or a quaternary ammonium base; preferably, the peeling agent is tetrabutylphosphonium hydroxide (TBPH).

12. The method of any one of claims 7 to 11, wherein, The "contacting" step completes the peeling and curling of the atomic layers within 0.1 seconds to 60 seconds; And / or, the "contacting" step is carried out with stirring or ultrasonic assistance. And / or, the method further comprises the step of washing, centrifuging and / or drying the obtained one-dimensional non-van der Waals superlattice material after curling formation.

13. An electromagnetic interference shielding assembly, characterized by, The assembly comprises a one-dimensional non-van der Waals superlattice material as claimed in any one of claims 1 to 6; or a one-dimensional non-van der Waals superlattice material obtained by the method as claimed in any one of claims 7 to 12.

14. The electromagnetic interference shielding assembly of claim 13, wherein, The one-dimensional non-van der Waals superlattice material in the assembly serves as a main electromagnetic wave attenuation phase; And / or, the assembly is in the form of a film, a coating, a foam, or a bulk composite.

15. The electromagnetic interference shielding assembly of claim 13, wherein, The assembly is in the form of a film; preferably, the film has a thickness between 1 μm and 100 μm. And / or, in the film, the one-dimensional non-van der Waals superlattice material is randomly distributed; And / or, in the film, the one-dimensional non-van der Waals superlattice material is preferentially aligned along at least one direction; And / or, the film is in a sandwich structure, comprising a highly aligned layer in the middle and two randomly distributed layers on both sides of the highly aligned layer; And / or, the film has a Hermans orientation factor no less than 0.

8.

16. The electromagnetic interference shielding assembly of any one of claims 13 to 15, wherein, The assembly has a total electromagnetic interference shielding effectiveness SE in the frequency range from 8.2 GHz to 12.4 GHz of not less than 80 dB; preferably, not less than 100 dB, more preferably, not less than 120 dB T not less than 80 dB; preferably, not less than 100 dB, more preferably, not less than 120 dB and / or the absorption shielding effectiveness SE of the assembly is A more than 50% of the total shielding effectiveness SE T . and / or the electrical conductivity of the assembly is not less than 5,000 S cm -1 , preferably not less than 10,000 S cm -1 ; and / or the absolute shielding effectiveness SSE / t of the assembly is not less than 50,000 dB cm 2 g -1 not less than 100,000 dB cm 2 g -1 more preferably not less than 150,000 dB cm 2 g -1 .

17. The electromagnetic interference shielding assembly of any one of claims 13 to 16, wherein, The assembly is in the form of a film, exhibiting flexibility and bendability; Preferably, the assembly further comprises a polymer matrix, in which the one-dimensional non-van der Waals superlattice material is dispersed or on the surface, forming a composite shielding material; and / or, after 10,000 bending cycles, the conductivity attenuation rate of the assembly is no more than 20%.

18. Use of a one-dimensional non-van der Waals superlattice material in the preparation of an electromagnetic interference shielding material, characterized in that, The one-dimensional non-van der Waals superlattice material is as described in any one of claims 1 to 11.

19. A system for preparing a one-dimensional nanomaterial oriented thin film, comprising: Comprising: a storage unit for holding a dispersion liquid comprising one-dimensional nanomaterials; an extrusion unit in fluid communication with the storage unit for extruding the dispersion liquid; an orientation unit comprising a slit channel configured to receive the dispersion liquid extruded from the extrusion unit and to orient the one-dimensional nanomaterials in the dispersion liquid along a flow direction by an applied shear force; a receiving unit for receiving the dispersion liquid extruded from the slit channel and having been oriented and to form a solid or semi-solid film therefrom.

20. The system of claim 19, wherein, The one-dimensional nanomaterials are one-dimensional non-van der Waals superlattice materials as described in any one of claims 1 to 12; Preferably, the concentration of the one-dimensional nanomaterials in the dispersion liquid is no less than 100 mg / mL, and / or, the dispersion liquid has liquid crystal properties, and / or, the dispersion liquid has a shear-thinning rheological property.

21. The system of claim 19 or 20, wherein, The extrusion unit comprises a syringe pump, a screw extruder, or a pneumatic driving device; And / or, the outlet of the slit channel is a flat needle or a linear slit die; preferably, the slit width of the flat needle or the linear slit die is between 10 μm and 1000 μm. And / or, the receiving unit comprises a translation stage or a rotating roller configured to move at a controllable speed to receive the oriented dispersion liquid; And / or, the receiving unit further comprises a heating device or a drying device for facilitating the solidification of the dispersion liquid. And / or, the system further comprises a flexible substrate disposed on the receiving unit, and the oriented dispersion liquid is extruded onto the flexible substrate to form a film thereon.

22. The system of any one of claims 19 to 21, wherein, The system further comprises a control unit communicatively connected with the extrusion unit and / or the receiving unit, the control unit being configured to control at least one of an extrusion speed, a receiving speed, and a distance between an extrusion outlet and a receiving surface; Preferably, the control unit is configured to coordinate the extrusion speed and the receiving speed to maintain a stable shear rate and a film thickness.

23. A method of preparing an oriented thin film of one-dimensional nanomaterials, comprising: Use of a system as claimed in any of claims 19 to 22.

24. A one-dimensional nanomaterial oriented thin film, comprising: a plurality of one-dimensional nanomaterials oriented in a direction. Prepared by a method as claimed in claim 23.

25. A one-dimensional nanomaterial oriented film, comprising: a plurality of one-dimensional nanomaterials oriented in a direction. The one-dimensional nanomaterial oriented film is formed by one-dimensional nanomaterials orderly arranged along a specific direction, and the one-dimensional nanomaterials contain the one-dimensional non-van der Waals superlattice material as claimed in any of claims 1 to 12; Preferably, the Hermann orientation factor of the one-dimensional nanomaterial oriented film is not less than 0.7; more preferably, not less than 0.8; and more preferably, not less than 0.85; And / or, the ratio of the electrical conductivity parallel to the specific direction to the electrical conductivity perpendicular to the specific direction of the one-dimensional nanomaterial oriented film satisfies: ≥ 2, preferably ≥ 5; And / or, the in-plane conductivity of the one-dimensional nanomaterial oriented film is not less than 5,000 S cm -1 , preferably, not less than 10,000 S cm -1 ; and more preferably, not less than 20,000 S cm -1 .

26. An electromagnetic interference shielding assembly, characterized by, The electronic device or apparatus contains the one-dimensional nanomaterial oriented film as claimed in any of claims 19 to 25.

27. An electronic device or apparatus, characterized by The electronic device or apparatus contains the one-dimensional van der Waals superlattice material as claimed in any of claims 1 to 12, the electromagnetic interference shielding assembly as claimed in any of claims 13 to 17, or the one-dimensional nanomaterial oriented film as claimed in any of claims 19 to 25. Preferably, the electronic device or apparatus is a sensor, a chip, a mobile phone, a base station, a notebook computer, a wearable device, a car, a ship, an aerospace vehicle, or a military radar.

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