Preparation of two-dimensional material double-layer twisted-angle MoSe2 and two-dimensional material double-layer twisted-angle MoSe2
By constructing a confined reaction space in two-dimensional materials using chemical vapor deposition and employing sodium chloride salt, combined with a back-to-back substrate design, high-quality in-situ growth of bilayer twisted MoSe2 was achieved. This solved the problems of interface contamination and angle control in existing technologies, and improved the manufacturability and fault tolerance of the devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NORTHWESTERN POLYTECHNICAL UNIV
- Filing Date
- 2026-03-11
- Publication Date
- 2026-05-29
AI Technical Summary
Existing technologies struggle to achieve high-quality, low-cost preparation of two-dimensional bilayer twisted MoSe2 materials, and also suffer from problems such as interface contamination and difficulty in angle control.
By employing a one-step chemical vapor deposition method, and by constructing a "tube-in-tube" confined reaction space and using sodium chloride as a growth promoter, combined with precise control of atmosphere timing and back-to-back substrate design, in-situ growth of bilayer twisted MoSe2, a two-dimensional material, was achieved.
A two-dimensional material, bilayer twisted MoSe2, with uniform surface, clean interface, and high crystal quality, was successfully prepared, solving the problems of interface contamination and angle control in traditional methods and improving the manufacturability and fault tolerance of the device.
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Figure CN122102066A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of nanomaterial preparation technology, and in particular to the preparation of a two-dimensional material bilayer twisted MoSe2 and the two-dimensional material bilayer twisted MoSe2. Background Technology
[0002] In 2023, the fractional quantum anomalous Hall effect observed in a two-dimensional twisted material system confirmed that strongly correlated topological states can be realized through a moiré superlattice potential even in zero magnetic field, providing a new physical foundation for topological quantum computing. In this cutting-edge field, MoSe2, with its tunable bandgap, strong spin-orbit coupling, and unique valley degrees of freedom, has become a highly promising research platform. Notably, the bilayer twisted MoSe2 structure significantly improves the manufacturability and fault tolerance of devices. This structure can realize a wide range of physical phenomena without relying on complex multilayer stacking, providing an ideal physical platform for directly studying quantum properties such as strongly correlated insulating states, magnetic states, or topological superconductivity, as well as developing novel optoelectronic, catalytic, and electronic devices.
[0003] Currently, existing preparation techniques still have significant limitations. The method reported in *Nanoscale, 2023, 15, 7792* is limited to guiding the second layer to form a "flower-like" morphology through specific helical dislocations, making it difficult to achieve universal interlayer angle control. The mechanism described in *The Journal of Physical Chemistry C, 2024, 128, 19849* heavily relies on uncontrollable local gas flow fluctuations and only reports a 33° twisted sample, lacking reproducibility and controllability. Therefore, developing a simple, low-cost method for preparing high-quality twisted MoSe2 with clean interfaces and smooth surfaces in situ has become an urgent technical challenge. To address the shortcomings of the existing technologies, this invention proposes a one-step chemical vapor deposition method that successfully overcomes the bottleneck of angle control, achieving high-quality preparation of two-dimensional twisted MoSe2. Summary of the Invention
[0004] The purpose of this invention is to provide a method for preparing a two-dimensional material bilayer twisted MoSe2 and a two-dimensional material bilayer twisted MoSe2, in order to solve the problems of complex preparation process, serious interface contamination and difficulty in directly growing high-quality twisted structures in the prior art.
[0005] To achieve the above objectives, the technical solution adopted by the present invention includes: A method for preparing a two-dimensional material bilayer twisted MoSe2 includes the following steps: setting up a reaction chamber, with a selenium source placed in the upstream region of the reaction chamber; setting up an inner tube with openings at both ends in the downstream region of the reaction chamber, with a molybdenum source and a growth substrate placed in the inner tube; introducing a carrier gas into the reaction chamber and heating the reaction chamber to reach the reaction temperature, and growing the two-dimensional material bilayer twisted MoSe2 on the growth substrate by chemical vapor deposition; the carrier gas is introduced in the following manner: argon gas is introduced during the heating stage, and hydrogen gas is introduced after the reaction system reaches the reaction temperature, and the chemical vapor deposition is carried out in a mixed atmosphere of argon and hydrogen gas. After the reaction is completed, the introduction of hydrogen gas is stopped and the introduction of argon gas is continued.
[0006] Optionally, the carrier gas is introduced as follows: during the heating and temperature rise stage, 40-70 sccm of argon gas is introduced; after the reaction system reaches the reaction temperature, 5-25 sccm of hydrogen gas is introduced; the chemical vapor deposition is carried out in an atmosphere of argon and hydrogen with a hydrogen content of 20%; after the reaction is completed, the hydrogen gas is stopped and argon gas is introduced at 56 sccm.
[0007] Optionally, the flow rate of argon is 56 sccm; the flow rate of hydrogen is 14 sccm.
[0008] Optionally, the heating rate of the carrier gas is 10–50 °C / min; the reaction temperature of the chemical vapor deposition is 750–900 °C; and the growth time of the chemical vapor deposition is 5–30 min.
[0009] Optionally, the molybdenum source is molybdenum trioxide powder or molybdenum chloride powder; the selenium source is selenium powder; the amount of the molybdenum source is 1-4 mg; and the amount of the selenium source is sufficient.
[0010] Optionally, a growth promoter, namely sodium chloride, is added to the molybdenum source, and the mass ratio of molybdenum source to growth promoter is 3:1 to 5:1.
[0011] Optionally, the growth substrate is placed as follows: two silicon dioxide / silicon wafers are used as substrates, the silicon surfaces of the two substrates are bonded together, and the silicon dioxide surfaces face outwards, and they are stacked in the inner tube.
[0012] Optionally, the molybdenum source is placed 0.5 to 1.5 cm upstream of the gas flow from the growth substrate; the selenium source is placed 10 to 12 cm upstream of the molybdenum source gas flow and is located in the thermal radiation zone of the reaction chamber.
[0013] Optionally, the inner diameter of the inner tube is 8-12 mm; the inner diameter of the outer tube is 20-30 mm.
[0014] A two-dimensional material double-layer twisted angle MoSe2 is prepared by any of the preparation methods of the two-dimensional material double-layer twisted angle MoSe2 described in this invention.
[0015] Advantages of this invention: (1) Improve the growth environment by using confined space and salt assistance. By constructing a confined reaction space of “tube within a tube” and combining it with the sodium chloride salt assisted growth strategy, the confined space’s constraint on gas phase transport and the halide salt’s regulation of the metal source’s melting point and volatility are utilized to significantly improve the vapor pressure and nucleation density of the local reaction source, effectively solving the problem of uneven precursor distribution in traditional CVD methods.
[0016] (2) Twisted structure induced by precise control of atmosphere timing. By strictly limiting the introduction of hydrogen only during the high-temperature growth stage, this invention not only avoids unexpected oxidation or reduction side reactions of the molybdenum source during the heating process, but also cleverly utilizes the etching mechanism of hydrogen on lattice defects and thermodynamically unstable stacking at high temperatures, successfully inducing and stabilizing a bilayer structure with twisted angles.
[0017] (3) High production capacity is achieved by using back-to-back substrate arrangement. The unique design of back-to-back substrate stacking increases the yield per experiment while optimizing the micro-hydrodynamic environment on the substrate surface, ensuring stable product growth.
[0018] (4) The in-situ growth process ensures the extreme cleanliness of the interlayer interface. Compared with the traditional mechanical exfoliation and transfer technology, the present invention realizes one-step in-situ preparation, ensuring the natural cleanliness of the interlayer interface and the absence of polymer residue, and preserving the intrinsic optoelectronic properties of the two-dimensional twisted MoSe2 to the greatest extent, providing a high-quality material basis for the development of novel twisted optoelectronics and optoelectronic integrated devices. Attached Figure Description
[0019] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the experimental preparation of the embodiments and comparative examples in this invention; Figure 2 This is an optical microscope photograph of Example 1 of the present invention; Figure 3 This is the Raman spectrum of Example 1 in this invention; Figure 4 This is an optical microscope photograph of Example 2 of the present invention; Figure 5 This is the Raman spectrum of Example 2 in this invention; Figure 6This is an optical microscope photograph of Example 3 of the present invention; Figure 7 This is the Raman spectrum of Example 3 in this invention; Figure 8 This is an optical microscope photograph of Comparative Example 1 in this invention; Figure 9 This is the Raman spectrum of Comparative Example 1 in this invention.
[0020] Figure 10 This is an optical microscope photograph of Comparative Example 2 in this invention. Detailed Implementation
[0021] To make the objectives and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments, and the advantages of the invention will be demonstrated through the analysis of comparative examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
[0022] The two-dimensional bilayer twisted MoSe2 material prepared in this invention is grown directly in situ on a silicon dioxide / silicon substrate using an improved chemical vapor deposition method. By introducing sodium chloride as a growth promoter and combining it with a dual-tube confinement space design, factors such as the proportion of reaction source, reaction temperature of 750-900℃, growth time, and the timing of carrier gas introduction are precisely controlled, resulting in high-quality two-dimensional bilayer twisted MoSe2 material. This process route is not only simple and low-cost, but also successfully prepares two-dimensional bilayer twisted MoSe2 material with uniform surface, no interface contamination, and high crystal quality, effectively solving the interface contamination problem caused by traditional transfer methods.
[0023] Specifically, the method for preparing the two-dimensional material bilayer twisted MoSe2 of the present invention uses silicon dioxide / silicon wafers as substrates. Preferably, the non-growth surfaces of two substrates are stacked back-to-back, and growth is performed on the silicon dioxide surface of the substrate, which serves as the growth surface, using chemical vapor deposition. The growth container is an outer quartz tube, and the carrier gas inside the quartz tube is a mixture of an inert gas containing argon and a reducing gas containing hydrogen. Following the flow direction of the carrier gas, selenium powder, serving as a selenium source, is placed in the upstream thermal radiation zone of the outer quartz tube. A small-diameter quartz test tube with openings at both ends is placed downstream of the selenium source as an inner tube. Molybdenum trioxide, serving as a molybdenum source, sodium chloride, serving as a growth promoter, and the substrate are placed inside this quartz test tube. In a preferred embodiment, the flow rate of the carrier gas is controlled to be 40–70 sccm for argon and 5–25 sccm for hydrogen; the reaction temperature for chemical vapor deposition is 750–900°C. It is particularly noteworthy that hydrogen is only introduced during the isothermal growth stage after the reaction temperature is reached.
[0024] Through extensive experiments, the inventors discovered that the construction of the reaction space is crucial to the product structure: chemical vapor deposition (CVD) must be carried out within the confined space constructed by an inner tube (a quartz tube open at both ends) to stably obtain two-dimensional twisted MoSe2 material. If this two-end open quartz tube is not used, for example, if an open quartz boat or crucible is placed directly in the outer tube, due to insufficient local precursor concentration and turbulent flow field, only thermodynamically stable monolayers or multilayers of 2H-phase MoSe2 are typically obtained on the substrate. The layers tend to naturally stack at 0 degrees or 60 degrees, making it difficult to induce twisting. Specifically: The method for preparing the two-dimensional material bilayer twisted MoSe2 of the present invention employs a chemical vapor deposition system. The system includes a quartz tube as an outer tube and an inner tube (a confined space component) disposed inside the quartz tube and open at both ends. The method includes the following steps: (1) Substrate loading: Two silicon dioxide / silicon wafers are used as growth substrates and stacked back to back with the non-growth surfaces (i.e., silicon surfaces) touching each other and the growth surfaces (i.e., silicon dioxide surfaces) facing outwards respectively, and placed in the inner tube. (2) Source configuration: The mixture of molybdenum source and growth promoter is placed in the inner tube and located upstream of the gas flow of the growth substrate; the selenium source is placed in the upstream region of the quartz tube and located in the thermal radiation zone of the tube furnace; (3) Atmosphere control and growth: The reaction system is sealed, and inert gas is first introduced to purge the air; the reaction system is heated at a heating rate of 10-50℃ / min; only inert gas is introduced during the heating stage; when the reaction temperature reaches 750-900℃, hydrogen is introduced into the system, and the system is grown at a constant temperature for 5-30 min in a mixed atmosphere of inert gas and hydrogen to obtain a two-dimensional material double-layer twisted MoSe2 on the growth substrate. Specifically, the carrier gas is introduced as follows: 40-70 sccm of argon is introduced during the heating stage; when the reaction system reaches the reaction temperature, 5-25 sccm of hydrogen is introduced; the chemical vapor deposition is carried out in a mixed atmosphere of argon and hydrogen with a hydrogen content of 20%; after the reaction is completed, the hydrogen is stopped and argon is introduced at 56 sccm.
[0025] The molybdenum source is molybdenum trioxide powder or molybdenum chloride powder; the selenium source is selenium powder.
[0026] The growth promoter is sodium chloride; the mass ratio of molybdenum source to growth promoter is 3:1 to 5:1.
[0027] The molybdenum source dosage is 1–4 mg; the selenium source dosage is sufficient.
[0028] During the growth stage, the inert gas is argon with a flow rate of 40–70 sccm; the flow rate of hydrogen is 5–25 sccm.
[0029] The positional relationship is as follows: the molybdenum source is placed 0.5 to 1.5 cm upstream of the gas flow from the growth substrate; the selenium source is placed 10 to 12 cm upstream of the gas flow from the molybdenum source.
[0030] The inner diameter of the inner tube is 8–12 mm; the inner diameter of the outer tube is 20–30 mm.
[0031] The present invention also provides a two-dimensional material, double-layer twisted MoSe2, prepared by the above method, which has obvious moiré fringe characteristics and clean and uncontaminated interlayer interfaces.
[0032] A two-dimensional material, bilayer twisted MoSe2, is prepared using the preparation method of the two-dimensional material bilayer twisted MoSe2 of the present invention.
[0033] Unless otherwise specified, all raw materials used in the following embodiments are commercially available analytical grade, all instruments used are conventional laboratory instruments, and all methods used are conventional experimental methods in the art.
[0034] Example 1: This embodiment presents a method for preparing a two-dimensional bilayer twisted MoSe2 material on a silicon dioxide / silicon substrate, comprising the following steps: Step 1: Cut the silicon dioxide / silicon substrate into 0.9×3cm sheets and clean them with an air gun. Place the silicon dioxide sides face down in a quartz test tube with open ends and an inner diameter of 10mm.
[0035] Step 2: Add 2 mg of molybdenum trioxide powder to the front 1 cm of the substrate, and add 0.5 mg of NaCl to the molybdenum trioxide powder.
[0036] Step 3: Place a quartz test tube into a quartz tube with an outer diameter of 25 mm. Add molybdenum trioxide powder and NaCl to one end near the gas inlet. The Se source and molybdenum source are 11 cm apart. Heat in a tubular atmosphere furnace at the center to perform chemical vapor deposition of a two-dimensional double-layer twisted MoSe2 material. Figure 1 As shown in a.
[0037] Step 4: Argon gas was introduced at a flow rate of 800 sccm for 30 minutes to thoroughly remove residual oxygen and impurities from the tube. Subsequently, the argon flow rate was reduced to 56 sccm, and the tubular furnace was heated to 840°C at a heating rate of 30°C / min under an inert atmosphere with only argon gas introduced. Once the furnace temperature reached and stabilized at 840°C, the hydrogen gas path was immediately opened, and hydrogen gas was introduced at a flow rate of 14 sccm. Chemical vapor deposition growth was carried out for 8 minutes under a mixed atmosphere of argon and hydrogen. After growth, the hydrogen gas was immediately shut off, while maintaining a constant argon flow rate, and the heater was turned off. The reaction system was allowed to cool naturally to room temperature under the protection of the argon atmosphere. The resulting optical image of the two-dimensional bilayer twisted MoSe2 material is shown below. Figure 2As shown. By Figure 2 Optical photographs show that the prepared material is a bilayer twisted MoSe2 with a twist angle of 100°. Raman spectra are as follows. Figure 3 As shown, both positions 1 and 2 have Raman characteristic peaks of MoSe2, indicating that the prepared material is MoSe2.
[0038] Example 2: This embodiment presents a method for preparing a two-dimensional bilayer twisted MoSe2 material on a silicon dioxide / silicon substrate, comprising the following steps: Step 1: Cut the silicon dioxide / silicon substrate into 0.9×3cm sheets and clean them with an air gun. Place the silicon dioxide sides face down in a quartz test tube with open ends and an inner diameter of 10mm.
[0039] Step 2: Add 3mg of molybdenum trioxide powder to the front 1cm of the substrate, and add 1mg of NaCl to the molybdenum trioxide powder.
[0040] Step 3: Place a quartz test tube into a quartz tube with an outer diameter of 25 mm. Add molybdenum trioxide powder and NaCl to one end near the gas inlet. The Se source and molybdenum source are 11 cm apart. Heat in a tubular atmosphere furnace at the center to perform chemical vapor deposition of a two-dimensional double-layer twisted MoSe2 material. Figure 1 As shown in a.
[0041] Step 4: Argon gas was introduced at a flow rate of 800 sccm for 30 minutes to thoroughly remove residual oxygen and impurities from the tube. Subsequently, the argon flow rate was reduced to 56 sccm, and the tubular furnace was heated to 840°C at a heating rate of 30°C / min under an inert atmosphere with only argon gas introduced. Once the furnace temperature reached and stabilized at 840°C, the hydrogen gas path was immediately opened, and hydrogen gas was introduced at a flow rate of 14 sccm. Chemical vapor deposition growth was carried out for 8 minutes under a mixed atmosphere of argon and hydrogen. After growth, the hydrogen gas was immediately shut off, while maintaining a constant argon flow rate, and the heater was turned off. The reaction system was allowed to cool naturally to room temperature under the protection of the argon atmosphere. The resulting optical image of the two-dimensional bilayer twisted MoSe2 material is shown below. Figure 4 As shown, by Figure 4 Optical photographs show that the prepared material is a bilayer twisted MoSe2 with a twist angle of 97°. Raman spectra are as follows. Figure 5 As shown, both positions 1 and 2 have Raman characteristic peaks of MoSe2, indicating that the prepared material is MoSe2.
[0042] Example 3: This embodiment presents a method for preparing a two-dimensional bilayer twisted MoSe2 material on a silicon dioxide / silicon substrate, comprising the following steps: Step 1: Cut the silicon dioxide / silicon substrate into 0.9×3cm sheets and clean them with an air gun. Place the silicon dioxide sides face down in a quartz test tube with open ends and an inner diameter of 10mm.
[0043] Step 2: Add 4 mg of molybdenum trioxide powder to the front 1 cm of the substrate, and add 2 mg of NaCl to the molybdenum trioxide powder.
[0044] Step 3: Place a quartz test tube into a quartz tube with an outer diameter of 25 mm. Add molybdenum trioxide powder and NaCl to one end near the gas inlet. The Se source and molybdenum source are 11 cm apart. Heat in a tubular atmosphere furnace at the center to perform chemical vapor deposition of a two-dimensional double-layer twisted MoSe2 material. Figure 1 As shown in a.
[0045] Step 4: Argon gas was introduced at a flow rate of 800 sccm for 30 minutes to thoroughly remove residual oxygen and impurities from the tube. Subsequently, the argon flow rate was reduced to 56 sccm, and the tubular furnace was heated to 840°C at a heating rate of 30°C / min under an inert atmosphere with only argon gas introduced. Once the furnace temperature reached and stabilized at 840°C, the hydrogen gas path was immediately opened, and hydrogen gas was introduced at a flow rate of 14 sccm. Chemical vapor deposition growth was carried out for 8 minutes under a mixed atmosphere of argon and hydrogen. After growth, the hydrogen gas was immediately shut off, while maintaining a constant argon flow rate, and the heater was turned off. The reaction system was allowed to cool naturally to room temperature under the protection of the argon atmosphere. The resulting optical image of the two-dimensional bilayer twisted MoSe2 material is shown below. Figure 6 As shown, by Figure 6 Optical photographs show that the prepared material is a bilayer twisted MoSe2 with a twist angle of 108°. Raman spectra are as follows. Figure 7 As shown, positions 1 and 2 both exhibit Raman characteristic peaks of MoSe2, indicating that the prepared material is MoSe2. The Raman spectrum is as follows: Figure 7 As shown.
[0046] Comparative Example 1: This comparative example provides a method for preparing materials without using a quartz test tube open at both ends, including the following steps: Step 1: Same as Example 1 Step 2: Same as in Example 1 Step 3: Place the quartz crucible into a quartz tube with an outer diameter of 25mm. Add molybdenum trioxide powder and NaCl, placing one end near the gas inlet. The Se source and molybdenum source should be 11cm apart. Place the crucible directly in the center of the tubular atmosphere furnace for heating. Figure 1 As shown in b.
[0047] Step 4: Same as in Example 1, the MoSe2 optical image obtained at this time is as follows. Figure 8 As shown, the Raman spectrum is as follows Figure 9 As shown.
[0048] Compared with Example 1, it can be seen that without using a quartz test tube with openings at both ends as the cavity, under the condition that other conditions remain unchanged, the material prepared on the substrate is a single layer or multiple layers of MoSe2, and there will be no twisting between the layers, and no two-dimensional material double-layer twisted MoSe2 will be generated on the substrate.
[0049] Comparative Example 2: This comparative example provides a method for preparing materials using only an inert gas atmosphere without introducing hydrogen gas during the isothermal growth stage, including the following steps: Step 1: Same as Example 1.
[0050] Step 2: Same as in Example 1.
[0051] Step 3: Same as in Example 1.
[0052] Step 4: Maintain the same tube washing and heating procedures as in Example 1. Once the furnace temperature reaches and stabilizes at 840°C, do not turn on the hydrogen gas supply; instead, maintain an argon gas flow rate of 56 sccm and hold at a constant temperature for 8 minutes in a pure argon atmosphere. After growth, allow it to cool naturally to room temperature. The resulting MoSe2 optical image is shown below. Figure 10 As shown.
[0053] Optical microscopy revealed that without the introduction of hydrogen, only a few scattered, extremely small polycrystalline particles appeared on the substrate surface. MoSe2 grains with a complete triangular morphology failed to grow, and the bilayer twisted structure was not observable. This comparative example demonstrates the necessity of hydrogen in the high-temperature growth stage. Hydrogen not only acts as a reduction aid, enhancing the reactivity of the precursor, but more importantly, as described in the invention, hydrogen has an etching mechanism for lattice defects and thermodynamically unstable stacking at high temperatures, which is a necessary condition for inducing and stabilizing the twisted bilayer structure. Without hydrogen, the reaction system cannot achieve the synergistic growth of high-quality bilayer twisted MoSe2.
[0054] The above description is only an optional embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing a two-dimensional material, bilayer twisted MoSe2, characterized in that, Includes the following steps: A reaction chamber is set up, with a selenium source placed in the upstream region of the reaction chamber; an inner tube with openings at both ends is set up in the downstream region of the reaction chamber, with a molybdenum source and a growth substrate placed in the inner tube; A carrier gas is introduced into the reaction chamber and heated to the reaction temperature. A two-dimensional material, bilayer twisted MoSe2, is grown on the growth substrate by chemical vapor deposition. The carrier gas is introduced as follows: argon is introduced during the heating and temperature rise stage. After the reaction system reaches the reaction temperature, hydrogen is introduced. The chemical vapor deposition is carried out in a mixed atmosphere of argon and hydrogen. After the reaction is completed, the introduction of hydrogen is stopped and argon is introduced again.
2. The method for preparing two-dimensional bilayer twisted MoSe2 according to claim 1, characterized in that, The carrier gas is introduced as follows: during the heating and temperature rise stage, 40-70 sccm of argon gas is introduced. After the reaction system reaches the reaction temperature, 5-25 sccm of hydrogen gas is introduced. The chemical vapor deposition is carried out in an atmosphere of argon and hydrogen with a hydrogen content of 20%. After the reaction is completed, the hydrogen gas is stopped and argon gas is introduced at 56 sccm.
3. The method for preparing a two-dimensional bilayer twisted MoSe2 material according to claim 1 or 2, characterized in that, The flow rate of argon is 56 sccm; the flow rate of hydrogen is 14 sccm.
4. The method for preparing a two-dimensional bilayer twisted MoSe2 material according to claim 1 or 2, characterized in that, The heating rate of the carrier gas is 10–50 °C / min; the reaction temperature of the chemical vapor deposition is 750–900 °C; and the growth time of the chemical vapor deposition is 5–30 min.
5. The method for preparing a two-dimensional bilayer twisted MoSe2 material according to claim 1 or 2, characterized in that, The molybdenum source is molybdenum trioxide powder or molybdenum chloride powder; the selenium source is selenium powder; the amount of molybdenum source used is 1-4 mg; the amount of selenium source used is sufficient.
6. The method for preparing a two-dimensional bilayer twisted MoSe2 material according to claim 1 or 2, characterized in that, A growth promoter, sodium chloride, is added to the molybdenum source, and the mass ratio of the molybdenum source to the growth promoter is 3:1 to 5:
1.
7. The method for preparing a two-dimensional material bilayer twisted MoSe2 according to claim 1 or 2, characterized in that, The specific placement method of the growth substrate is as follows: two silicon dioxide / silicon wafers are used as substrates, the silicon surfaces of the two substrates are bonded together, and the silicon dioxide surfaces are respectively facing outwards, and they are stacked in the inner tube.
8. The method for preparing a two-dimensional bilayer twisted MoSe2 material according to claim 1 or 2, characterized in that, The molybdenum source is placed 0.5–1.5 cm upstream of the gas flow from the growth substrate; The selenium source is placed 10-12 cm upstream of the molybdenum source gas flow and is located in the thermal radiation zone of the reaction chamber.
9. The method for preparing a two-dimensional bilayer twisted MoSe2 material according to claim 1 or 2, characterized in that, The inner diameter of the inner tube is 8-12 mm; the inner diameter of the outer tube is 20-30 mm.
10. A two-dimensional material, double-layer twisted MoSe2, characterized in that, The two-dimensional material bilayer twisted angle MoSe2 is prepared using the preparation method of the two-dimensional material bilayer twisted angle MoSe2 according to any one of claims 1-9.