One-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons and their preparation methods and applications

Abstract

The present invention discloses a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon, a preparation method thereof, and an application thereof. The preparation method includes: using a salt-assisted chemical vapor deposition method, taking bismuth trioxide, tellurium, and an inorganic salt as growth precursors, and growing a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon on a growth substrate. The preparation method provided by the present invention synthesizes, for the first time, a one-dimensional layered bismuth tellurium oxide nanoribbon with room-temperature ferroelectricity by an atmospheric pressure chemical vapor deposition method. Its thickness is close to that of a single layer of bismuth tellurium oxide, and the width of the nanoribbon can be adjusted within the range of several nanometers to several hundred nanometers, providing an idea for the preparation of low-dimensional ferroelectric materials, and providing the possibility and broad application prospects for the size reduction and performance improvement of ferroelectric memory devices; moreover, the entire growth process of the preparation method of the present invention is relatively simple and has low energy consumption.

Description

Technical Field

[0001] The present invention relates to a bismuth tellurium oxide material, in particular to a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon and a preparation method and application thereof, belonging to the field of nanoscience and technology. Background Art

[0002] Since the discovery of graphene, two-dimensional layered materials have shown novel electrical, magnetic, thermal and mechanical properties due to their atomic-scale thickness, such as valleytronics (Nature Nanotechnology, 2012, 7: 490-493), quantum anomalous Hall effect, topological insulators, ultra-high thermal conductivity and mechanical strength, etc., which are difficult to exist in bulk materials. These properties have attracted extensive attention and research, and are expected to develop high-performance micro-nano devices that can improve or replace existing devices.

[0003] Ferroelectric materials are materials that play an important role in electronics. Due to their rapid switching polarization under an applied voltage, they are widely used in fields such as field-effect transistors, non-volatile memories, micro-electro-mechanical systems and actuators. In the past century, many bulk ferroelectric materials have been discovered. Currently, ferroelectric materials mainly include traditional perovskite materials, as well as two-dimensional ferroelectric nanosheets and layered perovskite materials that have emerged in recent years. Traditional ferroelectric materials are mainly complex oxides with a perovskite structure, such as BaTiO 3 3 3 3 3 3and BiFeO

[0004] 2 (M = Mo, W, X = S, Se)(Nature, 2014, 514: 470-474) transition metal dichalcogenides (TMDCs), Group IV monochalcogenides (SnTe, SnSe and GeSe)(Science, 2016, 353: 274-278), indium selenide (β-In 2 2 Se3 , α-In 2 Se 3 )(Nature Communications, 2017, 8(1): 14956), layered perovskite (Nature communications, 2016, 7(1): 1-9) and CuInP 2 S 6 (Nature Communications, 2016, 7(1): 12357), etc., and important breakthroughs have been achieved in related device application fields.

[0005] Compared with traditional ferroelectric materials, its advantages are mainly as follows: Compared with bulk ferroelectric materials, two-dimensional layered ferroelectric materials have their own naturally stable layered atomic structure and weak van der Waals interactions between layers, and are expected to achieve stable polarization in a few or even a single layer, thus enabling ferroelectric devices to reduce their size. However, it still has some disadvantages: The types of low-dimensional ferroelectric materials are still relatively scarce, the critical size of one-dimensional ferroelectric materials is not clear, and the growth mechanism needs to be further explored and optimized. Especially for one-dimensional nanoribbon ferroelectric materials, it is impossible to further reduce the size and improve the performance of ferroelectric devices.

[0006] Since nanostructures are usually used in low-dimensional forms, in addition to the discovered monolayer (2D) form, it is a scientifically significant and technically important task to study whether ferroelectricity is also maintained in lower-dimensional 1D nanoribbons. However, there is no report on the ferroelectric critical size of nanoribbons. Summary of the Invention

[0007] The main object of the present invention is to provide a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon and its preparation method to overcome the deficiencies in the prior art.

[0008] Another object of the present invention is to provide the application of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon.

[0009] To achieve the above invention objects, the present invention adopts the following technical solutions:

[0010] The embodiment of the present invention provides a preparation method of a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon, which includes: using a salt-assisted chemical vapor deposition method, with bismuth trioxide, tellurium and inorganic salt as growth precursors, and growing a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon on a growth substrate.

[0011] In some embodiments, the preparation method includes:

[0012] Mix bismuth trioxide, tellurium and inorganic salt evenly to form a growth precursor mixture;

[0013] Using a protective gas as the carrier gas, the growth precursor mixture and the growth substrate are jointly placed in the reaction chamber of a chemical vapor deposition device, and then the reaction chamber is heated to carry out the reaction to obtain the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon.

[0014] An embodiment of the present invention also provides a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon prepared by the foregoing preparation method, which is an atomic thin layer in the c direction and has ferroelectricity in the a / b direction.

[0015] An embodiment of the present invention also provides an application of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon in the preparation of ferroelectric memory devices.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] The preparation method provided by the present invention synthesizes one-dimensional layered bismuth tellurium oxide nanoribbons with room-temperature ferroelectricity for the first time by atmospheric pressure chemical vapor deposition. Its thickness is close to that of a single layer of bismuth tellurium oxide, and the width of the nanoribbon is adjustable within the range of several nanometers to several hundred nanometers, providing ideas for the preparation of low-dimensional ferroelectric materials, and providing possibilities and broad application prospects for the size reduction and performance improvement of ferroelectric memory devices; moreover, the entire growth process of the preparation method of the present invention is relatively simple and has low energy consumption. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 It is a flow schematic diagram of preparing a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon by atmospheric pressure CVD method in a typical embodiment of the present invention.

[0020] Figure 2a and Figure 2b It is an optical microscope image of a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon in a typical embodiment of the present invention.

[0021] Figures 3a - 3d It is an EDS-mapping image of a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon in a typical embodiment of the present invention.

[0022] Figure 4 It is an atomic force microscope (AFM) image of a one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon in a typical embodiment of the present invention.

[0023] Figure 5 It is a microscopic morphology image of the material obtained in Comparative Example 1.

[0024] Figure 6 It is the microscopic morphology diagram of the material obtained in Comparative Example 3.

[0025] Figure 7 It is the microscopic morphology diagram of the material obtained in Comparative Example 4. Detailed implementation manners

[0026] In view of the defects of the prior art, through long-term research and a large number of practices, the inventors of this case have proposed the technical solution of the present invention. The main idea is to synthesize one-dimensional layered bismuth tellurium oxide nanoribbons with room-temperature ferroelectricity for the first time by using atmospheric pressure chemical vapor deposition (APCVD), providing ideas for the preparation of low-dimensional ferroelectric materials, and providing possibilities and broad application prospects for the size reduction and performance improvement of ferroelectric memory devices.

[0027] As a non-linear optical (NLO) nanocrystal, bismuth tellurium oxide has attracted more and more attention in the applications of non-linear microphoton devices, bioimaging and holographic devices. When it changes from a bulk material to an atomically thin crystal, the symmetry breaking and the natural stable atomic layer structure break the critical size effect of the bulk material, making its atomically thin crystal expected to have ferroelectricity and be applied in the field of non-volatile memory.

[0028] The above technical solution, its implementation process and principle will be further explained below. However, it should be understood that within the scope of the present invention, the above technical features of the present invention and the technical features specifically described below (in the embodiments) can be combined with each other to form new or preferred technical solutions. Due to space limitations, they will not be repeated one by one here.

[0029] As an aspect of the technical solution of the present invention, a preparation method of one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons includes:

[0030] Using the method of salt-assisted chemical vapor deposition, with bismuth trioxide, tellurium and inorganic salts as growth precursors, one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons are grown on a growth substrate.

[0031] As one of the preferred solutions, the preparation method includes:

[0032] Mix bismuth trioxide, tellurium and inorganic salts evenly to form a growth precursor mixture;

[0033] Using a protective gas as a carrier gas, place the growth precursor mixture and the growth substrate together in the reaction chamber of a chemical vapor deposition device, and then heat the reaction chamber to carry out the reaction to obtain the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons.

[0034] As one of the more preferred embodiments, the preparation method specifically includes: heating the temperature of the reaction chamber to 500 - 700 °C at a heating rate of 10 - 50 °C / min, preferably 10 - 30 °C / min, and holding for a reaction for 1 - 60 min, preferably 1 - 15 min, and then rapidly cooling to room temperature. Among them, the heating rate is an auxiliary influencing factor. A heating rate of 10 - 50 °C / min is a common heating rate for growing nanoribbons, and 10 - 30 °C / min (preferably 25 °C / min) is the optimal heating rate for growing nanoribbons.

[0035] Among them, the growth temperature is a key influencing factor. The growth temperature can be 500 °C - 700 °C, and the optimal growth temperature is about 600 °C. Moreover, the growth time is a key influencing factor. The growth time can be 1 min - 60 min, and different growth conditions correspond to different morphologies of one-dimensional layered bismuth tellurium oxide nanosheets.

[0036] As one of the more preferred embodiments, the preparation method specifically further includes: after placing the growth precursor mixture and the growth substrate together in the reaction chamber of the chemical vapor deposition equipment, first introducing a protective gas to remove the air in the reaction chamber, and then heating up. Among them, the flow rate of the protective gas used is 300 sccm.

[0037] As one of the preferred embodiments, the inorganic salt includes sodium chloride, but is not limited thereto. Sodium chloride is the key to growing bismuth tellurium oxide nanoribbons. Otherwise, nanoribbon materials cannot be grown.

[0038] Further, the growth substrate includes a fluorophlogopite sheet, but is not limited thereto.

[0039] Further, the growth substrate is selected as a freshly dissociated fluorophlogopite sheet, which is inclined or parallelly arranged above the growth precursor mixture, or the growth precursor mixture can also be sandwiched between two adjacent growth substrates (freshly dissociated mica sheets).

[0040] Further, the protective gas includes argon, but is not limited thereto. Compared with the growth of traditional nanoribbons, the growth process of one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons uses the atmospheric pressure chemical vapor deposition method and uses Ar as the carrier gas. The whole growth process is relatively simple and has low energy consumption.

[0041] Further, during the reaction process, Ar is used as the carrier gas. The quartz tube is cleaned before growth, and the flow rate of the protective gas during the growth process is 80 - 150 sccm.

[0042] As one of the more preferred implementation schemes, please refer to Figure 1 As shown, the method for preparing one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons by the atmospheric pressure chemical vapor deposition method (APCVD) specifically includes:

[0043] Using an atmospheric pressure chemical vapor deposition system (Thermo Scientific LBM1100℃Mini-MiteTM single-zone tube furnace), bismuth trioxide (Bi 2 O 3 , 10-20 mg, Alfa-Aesar), tellurium powder (Te, 5-10 mg, Alfa-Aesar) and sodium chloride (NaCl, about 5 mg, Alfa-Aesar) are used as growth precursors, and mica is used as a growth substrate. 2 O 3 、TeO 2 Grind and mix with NaCl evenly, and place in a quartz boat (100mm×10mm×5mm). Then, a freshly dissociated mica sheet is used as a growth substrate, leaning against the precursor, and the quartz boat with the precursor and substrate is placed in the middle of the quartz tube of the tube furnace. The CVD growth system is closed, and argon (Ar, 99.995%, 300sccm) is passed for cleaning for 10 minutes. After 10 minutes, the Ar flow rate is adjusted from 300sccm to 80-150sccm, and the tube furnace is heated to 500-700℃ at a heating rate of 10-30℃ / min, and kept warm for 1-60 minutes. The quartz tube is then pushed out of the high temperature zone and quickly cooled to room temperature, thereby obtaining a one-dimensional layered bismuth telluride oxide ferroelectric nanobelt.

[0044] Among them, the cooling process is rapid cooling, which is to move the quartz tube directly out of the high temperature zone and quickly cool it to room temperature.

[0045] Among them, the precursor can not only be placed directly in a quartz boat, but also be sandwiched between two freshly dissociated mica sheets for spatially confined growth, and nanobelts can also be obtained.

[0046] In the salt-assisted atmospheric pressure chemical vapor deposition (APCVD) method adopted in the present invention, the selection of precursors and the placement of the growth substrate, the placement of the quartz boat, the selection of raw materials involved in the growth process, the heating rate, the growth temperature, the growth time, the gas flow rate, and the cooling program are all key technical indicators.

[0047] In summary, the growth process of the one-dimensional layered bismuth telluride ferroelectric nanobelts of the present invention involves a vapor-liquid-solid (VLS) growth mechanism, which enriches the growth system of the nanobelts and improves the growth mechanism of the nanobelts.

[0048] Another aspect of the embodiments of the present invention further provides a one-dimensional layered bismuth telluride ferroelectric nanobelt prepared by the aforementioned preparation method.

[0049] Specifically, compared with traditional ferroelectric materials, the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbon can be an atomic thin layer in the c direction and has ferroelectricity in the a / b direction, physically enriching ferroelectricity. Compared with emerging two-dimensional ferroelectric materials, its small size in the a / b direction enables higher integration, thus making ferroelectric devices smaller in size and higher in performance.

[0050] Through the above preparation method, the present invention first synthesized one-dimensional layered bismuth tellurium oxide nanoribbons with room-temperature ferroelectricity by atmospheric pressure chemical vapor deposition (APCVD). The thickness of the nanoribbons is close to that of a single layer of bismuth tellurium oxide, and the width of the nanoribbons can be adjusted within the range of several nanometers to several hundred nanometers. Specifically, the length of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons is 50 nm to 100 μm, and the width is 8 nm to 20 μm.

[0051] Further, the aspect ratio of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons is 10:1 to 500:1.

[0052] Further, the thickness of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons is 2 to 12 nm.

[0053] Another aspect of the embodiments of the present invention also provides an application of the aforementioned one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons in the preparation of ferroelectric memory devices.

[0054] By means of the above technical solution, the present invention grows one-dimensional ferroelectric nanoribbon materials through salt-assisted chemical vapor deposition, proves the possibility of the existence of ferroelectricity at the one-dimensional scale, enriches the types of low-dimensional ferroelectric materials, and provides a solution for further reducing the size and improving the performance of electronic devices relying on ferroelectricity.

[0055] In order to make the objectives, technical solutions and applications of the present invention clearer, the following further elaborates on the technical solutions of the present invention in conjunction with several preferred embodiments and accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention. The implementation conditions adopted in the following embodiments can be further adjusted according to actual needs, and the implementation conditions not specified are usually those in conventional experiments.

[0056] Example 1

[0057] As Figure 1 shown, the specific preparation steps of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons in this embodiment are as follows:

[0058] 1) Single-zone tube furnace CVD system: Thermo Scientific LBM1100℃ Mini-MiteTM single-zone tube furnace;

[0059] 2) Precursors: Bismuth(III) oxide (Bi 2 O 3 , 10 - 20 mg, Alfa - Aesar), tellurium powder (Te, 5 - 10 mg, Alfa - Aesar) and sodium chloride (NaCl, about 5 mg, Alfa - Aesar);

[0060] 3) Growth substrate: Freshly cleaved surface of fluorophlogopite mica sheet (Mica); Quartz boat: 100 mm × 10 mm × 5 mm;

[0061] 4) Mix Bi 2 O 3 , Te and NaCl evenly in a molar ratio of 1:1:1, place them in the quartz boat. Place the freshly cleaved mica sheet obliquely above the precursors, and place the quartz boat at the center of the constant - temperature zone of the tube furnace. Before growth, pass Ar gas with a flow rate of 300 sccm for 10 min to purge the residual air in the pipeline. Then adjust the Ar flow rate from 300 sccm to 100 sccm and stabilize for 1 min. Then, at a heating rate of 30 °C / min, raise the central temperature of the tube furnace to 700 °C, hold for 15 min, and then push the quartz tube out of the high - temperature zone and quickly cool it to room temperature to obtain one - dimensional layered bismuth tellurium oxide ferroelectric nanoribbons.

[0062] The inventors of this case also characterized and analyzed the prepared one - dimensional layered bismuth tellurium oxide ferroelectric nanoribbons, and the results are as follows:

[0063] Figure 2a and Figure 2b are the optical microscope images of the one - dimensional layered bismuth tellurium oxide ferroelectric nanoribbons. As can be seen from Figure 2a , the lengths of the nanoribbons vary from dozens of nanometers to several micrometers, and the widths vary from several nanometers to several micrometers. By adjusting the growth temperature, the morphology of one - dimensional layered bismuth tellurium oxide can be regulated, and nanosheets can be grown; by adjusting the growth time, the length and width of the nanoribbons, that is, the aspect ratio, can be adjusted. As can be seen from Figure 2b , the aspect ratio of the one - dimensional layered bismuth tellurium oxide ferroelectric nanoribbons can reach dozens to one or even five hundred to one, and the growth density can also be regulated according to the precursor concentration and carrier gas flow rate.

[0064] Figures 3a - 3d is the elemental spectrum map (EDS - mapping) of the one - dimensional layered bismuth tellurium oxide ferroelectric nanoribbons, which proves the elemental composition of bismuth tellurium oxide, and the distributions of Bi, Te, and O elements are very uniform.

[0065] Figure 4 is the atomic force microscope (AFM) image of the one - dimensional layered bismuth tellurium oxide nanoribbons. As can be seen from Figure 4It can be seen that the thickness of the nanoribbon is about 2 - 12 nm, and the thinner part can be close to the thickness of a single layer of bismuth tellurium oxide atoms.

[0066] Example 2

[0067] This example is the same as steps 1) - 3) of the example, the difference is that:

[0068] 4) Mix Bi 2 O 3 , Te and NaCl evenly at a molar ratio of 1:1:1, place them in a quartz boat, place a freshly cleaved mica sheet obliquely above the precursor, and place the quartz boat in the center of the constant temperature area of the tube furnace. Before growth, pass Ar gas with a flow rate of 300 sccm for 10 min to purge the residual air in the pipeline. Then adjust the Ar flow rate from 300 sccm to 80 sccm and stabilize for 1 min. Then, at a heating rate of 10 °C / min, raise the center temperature of the tube furnace to 500 °C, hold for 60 min, and then push the quartz tube out of the high-temperature zone and quickly cool it to room temperature to obtain one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons.

[0069] Example 3

[0070] This example is the same as steps 1) - 3) of the example, the difference is that:

[0071] 4) Mix Bi 2 O 3 , Te and NaCl evenly at a molar ratio of 1:1:1, place them in a quartz boat, place a freshly cleaved mica sheet obliquely above the precursor, and place the quartz boat in the center of the constant temperature area of the tube furnace. Before growth, pass Ar gas with a flow rate of 300 sccm for 10 min to purge the residual air in the pipeline. Then adjust the Ar flow rate from 300 sccm to 150 sccm and stabilize for 1 min. Then, at a heating rate of 50 °C / min, raise the center temperature of the tube furnace to 700 °C, hold for 1 min, and then push the quartz tube out of the high-temperature zone and quickly cool it to room temperature to obtain one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons.

[0072] Example 4

[0073] This example is the same as steps 1) - 3) of the example, the difference is that:

[0074] 4) Mix Bi 2 O 3, Te and NaCl are mixed evenly in a molar ratio of 1:1:1, placed in a quartz boat. Freshly dissociated mica sheets are placed obliquely above the precursor, and the quartz boat is placed at the center of the constant-temperature zone of the tube furnace. Before growth, Ar gas with a flow rate of 300 sccm is passed for 10 min to purge the residual air in the pipeline. Then the Ar flow rate is adjusted from 300 sccm to 120 sccm and stabilized for 1 min. Then, at a heating rate of 20 °C / min, the central temperature of the tube furnace is raised to 600 °C and held for 20 min. Then the quartz tube is taken out from the high-temperature zone and quickly cooled to room temperature, and one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons are obtained.

[0075] Comparative Example 1

[0076] Compared with Example 1, this comparative example is different in that: NaCl is not added. The morphology of the finally obtained material is as Figure 5 shown, and only two-dimensional flaky samples can be grown.

[0077] Comparative Example 2

[0078] Compared with Example 1, this comparative example is different in that: the central temperature of the tube furnace is raised to 400 °C. 400 °C does not reach the melting point of the growth raw materials, and no samples grow on the substrate.

[0079] Comparative Example 3

[0080] Compared with Example 1, this comparative example is different in that: the central temperature of the tube furnace is raised to 800 °C. At 800 °C, due to the too high temperature, the nanoribbons become wider and are connected into a sheet. The morphology of the finally obtained material is as Figure 6 shown.

[0081] Comparative Example 4

[0082] Compared with Example 1, this comparative example is different in that: the central temperature of the tube furnace is raised to 500 °C and the holding time is 30 min. At 500 °C and with too long a time, there are only flaky samples, but they are cracked in the middle and have a tendency to grow into ribbons. The morphology of the finally obtained material is as Figure 7 shown.

[0083] In addition, the inventors of this case also referred to the foregoing examples and conducted tests with other raw materials, process operations, and process conditions described in this specification, and all obtained relatively ideal results.

[0084] It should be understood that the above examples are only used to illustrate the technical concept and characteristics of the present invention, and their purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and cannot be used to limit the protection scope of the present invention. All equivalent transformations or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A preparation method of one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons, characterized in that, comprising: Mixing bismuth trioxide, tellurium and inorganic salt evenly to form a growth precursor mixture, and the inorganic salt is sodium chloride; Using a protective gas as a carrier gas, placing the growth precursor mixture and a growth substrate together in a reaction chamber of a chemical vapor deposition device, the growth substrate is inclined or parallelly arranged above the growth precursor mixture, or the growth precursor mixture is arranged between two adjacent growth substrates; then raising the temperature of the reaction chamber to 500-700 °C at a heating rate of 10-50 °C / min and keeping the temperature for reaction for 1-15 min to obtain one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons; The one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons are atomic thin layers in the c direction and have ferroelectricity in the a / b direction. The length of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons is 50 nm to 100 μm, and the width is 8 nm to 20 μm; the aspect ratio of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons is 10:1 to 500:

1.

2. The preparation method according to claim 1, characterized in that, comprising: Raising the temperature of the reaction chamber to 500-700 °C at a heating rate of 10-30 °C / min and keeping the temperature for reaction for 1-15 min, and then quickly cooling to room temperature.

3. The preparation method according to claim 1, characterized in that, further comprising: After placing the growth precursor mixture and the growth substrate together in the reaction chamber of the chemical vapor deposition device, first introducing a protective gas to remove the air in the reaction chamber, and then raising the temperature, wherein the flow rate of the protective gas used is 300 sccm.

4. The preparation method according to claim 1, characterized in that: The growth substrate is a fluorophlogopite sheet.

5. The preparation method according to claim 1, characterized in that: The protective gas is argon.

6. The preparation method according to claim 1, characterized in that: During the reaction process, the flow rate of the protective gas is 80-150 sccm.

7. The preparation method according to claim 1, characterized in that: The thickness of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons is 2-12 nm.

8. Application of the one-dimensional layered bismuth tellurium oxide ferroelectric nanoribbons prepared by the preparation method according to any one of claims 1-7 in the preparation of ferroelectric memory devices.

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