Method for growing V2O5 nanowire based on phase separation

Abstract

The invention discloses a method for growing a V2O5 nanowire based on phase separation. The method comprises the following steps: preparing a tungsten-vanadium oxide film on a substrate by adopting a sputter coating technology; and carrying out annealing treatment on the tungsten-vanadium oxide thin film, and inducing crystallization and phase separation processes of the tungsten-vanadium oxide thin film by the annealing treatment to obtain the V2O5 nanowire which takes WO3 as a substrate and grows on the WO3 substrate. The V2O5 nanowire can be prepared only through the sputter coating technology and the annealing technology, the technology is simple, large-scale production can be achieved, no catalyst or other chemical reagents are needed in the preparation process, and the method is environmentally friendly.

Description

Technical Field

[0001] The invention relates to the technical field of nano material preparation, and in particular to a method for growing V2O5 nanowires based on phase separation. Background Art

[0002] In recent years, vanadium pentoxide (V2O5) has broad application prospects in the fields of electrochromic, lithium batteries, gas sensors, etc. due to its multivalent state transition when ions are embedded and its unique layered structure. Compared with bulk V2O5, one-dimensional V2O5 nanowires have physical and chemical properties such as high specific surface area, significant anisotropy, and excellent size effect.

[0003] Most of the existing methods for preparing V2O5 nanowires are based on harsh conditions such as liquid phase, high temperature, and high pressure. The operations are complicated and a large amount of catalysts or other chemical reagents are required during the synthesis process. This not only increases the complexity of the reaction, but also reduces the purity of the product, increases the difficulty of subsequent separation and product purification, and to a certain extent limits its application in optoelectronic devices, energy storage, catalysis and other fields.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the present invention provides a method for growing V2O5 nanowires based on phase separation, so as to solve the problems of complex operation and harsh conditions in synthesizing V2O5 nanowires using the existing method.

[0006] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0007] The present invention provides a method for growing V2O5 nanowires based on phase separation, the method comprising the following steps:

[0008] The tungsten-vanadium oxide thin film was prepared on the substrate by sputtering coating technology;

[0009] The tungsten-vanadium oxide film is subjected to an annealing treatment, wherein the annealing treatment induces a crystallization and phase separation process of the tungsten-vanadium oxide film to obtain V2O5 nanowires grown on the WO3 substrate with WO3 as the substrate.

[0010] Preferably, the atomic ratio of tungsten to vanadium in the tungsten-vanadium oxide film is 1:(0.2-4).

[0011] Preferably, the sputtering coating technology is selected from magnetron sputtering technology, ion beam sputtering technology, and cathode arc sputtering technology.

[0012] Preferably, the substrate is selected from a glass substrate, a silicon substrate or a metal substrate.

[0013] Preferably, the step of preparing a tungsten-vanadium oxide thin film on a substrate by magnetron sputtering technology specifically includes:

[0014] The tungsten source target, the vanadium source target and the substrate are placed in a vacuum chamber of a magnetron sputtering device, and then a mixed gas of inert gas and oxygen is introduced into the vacuum chamber. The parameters of the magnetron sputtering device are adjusted to perform magnetron sputtering to prepare a tungsten vanadium oxide film on the substrate.

[0015] Preferably, the vacuum chamber of the magnetron sputtering equipment is evacuated to 10 -3 -10 -5 Pa vacuum state;

[0016] The pressure of the mixed gas in the vacuum chamber is 0.7Pa-5.0Pa;

[0017] The parameters of the magnetron sputtering equipment include: the sputtering power of the tungsten source target is 10-100W, the sputtering power of the vanadium source target is 50-200W, and the sputtering time is more than 0.3h.

[0018] Preferably, the flow ratio of the inert gas and oxygen is (2-5):1.

[0019] Preferably, the annealing temperature is 300°C-600°C.

[0020] Preferably, the annealing treatment time is 1h-15h.

[0021] Beneficial effects:

[0022] The present invention discloses a method for growing V2O5 nanowires based on phase separation, which can prepare V2O5 nanowires only through sputtering coating technology and annealing process. The process is simple and can be mass-produced. No catalyst or other chemical reagents are required during the preparation process, which is green and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a cross-sectional SEM image of the sample prepared in Example 1 of the present invention;

[0024] Figure 2 This is a SEM image of the sample surface prepared in Example 1 of the present invention;

[0025] Figure 3 XRD pattern of the sample prepared in Example 1 of the present invention;

[0026] Figure 4 TEM image of the V2O5 nanowire structure prepared in Example 1 of the present invention;

[0027] Figure 5 This is the selected area electron diffraction pattern of V2O5 nanowires prepared in Example 1 of the present invention;

[0028] Figure 6 This is the electron diffraction pattern of the WO3 substrate polycrystalline prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0029] The present invention provides a method for growing V2O5 nanowires based on phase separation. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0030] An embodiment of the present invention provides a method for growing V2O5 nanowires based on phase separation, the method comprising the following steps:

[0031] The tungsten-vanadium oxide thin film was prepared on the substrate by sputtering coating technology;

[0032] The tungsten-vanadium oxide film is subjected to an annealing treatment, wherein the annealing treatment induces a crystallization and phase separation process of the tungsten-vanadium oxide film to obtain V2O5 nanowires grown on the WO3 substrate with WO3 as the substrate.

[0033] Patent CN113658852A discloses a method for preparing silicon-based size-controllable β-Ga2O3 nanowires, wherein the preparation process of the silicon-based size-controllable β-Ga2O3 nanowires is as follows: first, a gold (Au) catalyst layer of different thicknesses is deposited on a single crystal Si (100) substrate, and the catalyst layer is subjected to in-situ spheroidization annealing to obtain Au nanoparticles of different sizes, and then β-Ga2O3 nanowires are grown by magnetron sputtering and in-situ annealing to obtain β-Ga2O3 nanowires of different sizes. The above patent is the mainstream method for growing nanowires in the traditional way. Compared with the above patent, the embodiment of the present invention can successfully prepare V2O5 nanowires without any catalyst.

[0034] Specifically, in the above patent, the gold nanoparticles function more as a seed crystal, and the β-Ga2O3 nanowires will grow around the gold nanoparticles. The size or morphology of the gold nanoparticles will affect the growth of the β-Ga2O3 nanowires, that is, the diameter and other morphological characteristics of the β-Ga2O3 nanowires are controlled by regulating the gold nanoparticles. However, this embodiment does not require such a function. It is a process of inducing crystallization and phase separation by affecting the internal structure and organization of the material through atomic diffusion under annealing treatment. Annealing treatment can induce the growth of V2O5 nanowires on the WO3 substrate, and V2O5 nanowires are directly prepared without any catalyst or other chemical substances.

[0035] In some embodiments, the atomic ratio of tungsten to vanadium in the tungsten-vanadium oxide film is 1:(0.2-4).

[0036] In some embodiments, the sputtering coating technology is selected from magnetron sputtering technology, ion beam sputtering technology, and cathode arc sputtering technology.

[0037] The tungsten-vanadium mixed amorphous oxide of the embodiment of the present invention is obtained by sputtering coating, specifically, ions bombard the surface of the target material to blast out the atoms on the surface of the target material, and then these sputtered particles are deposited on the surface of the substrate to form an oxide film. Sputtering coating methods include magnetron sputtering technology, ion beam sputtering technology, and cathode arc sputtering technology, but are not limited thereto.

[0038] In some embodiments, the substrate is selected from a glass substrate, a silicon substrate, or a metal substrate, but is not limited thereto.

[0039] The substrate used in the embodiment of the present invention may be a glass substrate, a silicon wafer or an aluminum wafer.

[0040] In some embodiments, the step of preparing a tungsten vanadium oxide thin film on a substrate using magnetron sputtering technology specifically includes:

[0041] The tungsten source target, the vanadium source target and the substrate are placed in a vacuum chamber of a magnetron sputtering device, and then a mixed gas of inert gas and oxygen is introduced into the vacuum chamber. The parameters of the magnetron sputtering device are adjusted to perform magnetron sputtering to prepare a tungsten vanadium oxide film on the substrate.

[0042] In some embodiments, the vacuum chamber of the magnetron sputtering device is evacuated to 10 -3 -10 -5 Pa vacuum state;

[0043] The pressure of the mixed gas in the vacuum chamber is 0.7-5.0Pa;

[0044] The parameters of the magnetron sputtering equipment include: the sputtering power of the tungsten source target is 10-100W, the sputtering power of the vanadium source target is 50-200W, and the sputtering time is more than 0.3h.

[0045] In some embodiments, the flow ratio of the inert gas and oxygen is (2-5):1.

[0046] In some embodiments, the annealing treatment is performed at a temperature of 300°C-600°C.

[0047] In some embodiments, the annealing treatment time is 1 hour to 15 hours.

[0048] In this embodiment, the length and density of the nanowires are controlled by adjusting the tungsten-vanadium atomic ratio and annealing parameters. Under the above-defined parameters, the length of the V2O5 nanowires is 10nm-4000nm.

[0049] In some embodiments, the present invention provides a method for growing V2O5 nanowires based on phase separation, the method comprising the following steps:

[0050] Place W and V targets on the target position in the vacuum chamber of the magnetron sputtering equipment;

[0051] placing the substrate on a sample stage;

[0052] The vacuum chamber is evacuated so that the vacuum degree in the vacuum chamber reaches a predetermined value, and the predetermined vacuum degree value is 10 -5 Pa magnitude;

[0053] Fill the vacuum chamber with argon and oxygen, and adjust the gas pressure to a predetermined range of 0.7-5.0 Pa;

[0054] Applying DC / RF current, regulating the sputtering power of W target and V target to control the atomic ratio of tungsten-vanadium mixed amorphous oxide, so that the atomic ratio of tungsten-vanadium is 1:(0.2-4), and the deposition rate can be adjusted by the sputtering power;

[0055] Change the scheduled deposition time to adjust the film thickness;

[0056] The deposited sample is annealed to crystallize and phase separate the sample to form a monoclinic WO3 substrate, and orthorhombic V2O5 nanowires are grown on the substrate. The annealing time and temperature are adjusted to control the length and density of the V2O5 nanowires. The annealing temperature range is 300°C-600°C, and the annealing time is more than 1 hour.

[0057] The embodiment of the present invention adopts W and V targets to co-sputter to prepare tungsten-vanadium mixed amorphous oxide. If tungsten-vanadium alloy target or other vanadium oxide target or tungsten oxide target is used for magnetron sputtering to prepare tungsten-vanadium mixed amorphous oxide, it also falls within the scope of the present invention.

[0058] The embodiment of the present invention uses an argon-oxygen mixed gas for magnetron sputtering. If other suitable gases are used for magnetron sputtering to prepare V2O5 nanowires, it falls within the scope of the present invention.

[0059] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and are only for illustrating the present invention but not limiting the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0060] Example 1

[0061] A V2O5 nanowire based on phase separation growth, the preparation method of which comprises the following steps:

[0062] The V target, W target and glass substrate were pre-installed into the vacuum chamber of the magnetron sputtering coating equipment, with a vacuum degree of 4×10 -5 Pa magnitude;

[0063] The DC sputtering power of the V target was regulated to 160W, the DC sputtering power of the W target was 40W, and an argon-oxygen mixed gas was introduced, wherein the oxygen gas was 15sccm and the argon gas was 45sccm. The pressure in the chamber was maintained at 2Pa, and the sputtering was performed for 2h to obtain a tungsten-vanadium mixed amorphous oxide with a thickness of about 300nm.

[0064] The obtained tungsten-vanadium mixed amorphous oxide was placed in a muffle furnace and annealed at 400°C for 2h in an atmospheric atmosphere to finally obtain a WO3 substrate and a sample on which V2O5 nanowires were grown.

[0065] The length of the prepared V2O5 nanowires is 100-250nm. Figure 1-6 The surface morphology was characterized by SEM and TEM; the crystal structure was determined by TEM and XRD. The V2O5 nanowires were single crystal structures belonging to the orthorhombic phase, and the WO3 substrate was a monoclinic phase structure.

[0066] Example 2

[0067] A V2O5 nanowire based on phase separation growth, the preparation method of which comprises the following steps:

[0068] The V target, W target and glass substrate were pre-installed into the vacuum chamber of the magnetron sputtering coating equipment, with a vacuum degree of 4×10 -4 Pa magnitude;

[0069] The DC sputtering power of the V target was regulated to 160W, the DC sputtering power of the W target was 40W, and an argon-oxygen mixed gas was introduced, wherein the oxygen gas was 15sccm and the argon gas was 45sccm. The pressure in the chamber was maintained at 2Pa, and the sputtering was performed for 2h to obtain a tungsten-vanadium mixed amorphous oxide with a thickness of about 300nm.

[0070] The obtained tungsten-vanadium mixed amorphous oxide was placed in a muffle furnace and annealed at 400°C for 4 hours in an atmospheric atmosphere to finally obtain V2O5 nanowires.

[0071] The length of the prepared V2O5 nanowires is 400-1200nm.

[0072] Example 3

[0073] A V2O5 nanowire based on phase separation growth, the preparation method of which comprises the following steps:

[0074] The V target, W target and glass substrate were pre-installed into the vacuum chamber of the magnetron sputtering coating equipment, with a vacuum degree of 4×10 -4 Pa magnitude;

[0075] The DC sputtering power of the V target was regulated to 160W, the DC sputtering power of the W target was 60W, and an argon-oxygen mixed gas was introduced, wherein the oxygen gas was 15sccm and the argon gas was 45sccm. The pressure in the chamber was maintained at 2Pa, and the sputtering was performed for 2h to obtain a tungsten-vanadium mixed amorphous oxide with a thickness of about 300nm.

[0076] The obtained tungsten-vanadium mixed amorphous oxide was placed in a muffle furnace and annealed at 400°C for 2h in an atmospheric atmosphere to finally obtain V2O5 nanowires.

[0077] The length of the prepared V2O5 nanowires is 100-300nm.

[0078] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for growing V2O5 nanowires based on phase separation, characterized in that: The method comprises the following steps: The tungsten-vanadium oxide thin film was prepared on the substrate by sputtering coating technology; The tungsten-vanadium oxide film is subjected to an annealing treatment, wherein the annealing treatment induces a crystallization and phase separation process of the tungsten-vanadium oxide film to obtain V2O5 nanowires grown on the WO3 substrate with WO3 as the substrate.

2. The method for growing V2O5 nanowires based on phase separation according to claim 1, characterized in that: The atomic ratio of tungsten to vanadium in the tungsten-vanadium oxide film is 1:(0.2-4).

3. The method for growing V2O5 nanowires based on phase separation according to claim 1, characterized in that: The sputtering coating technology is selected from magnetron sputtering technology, ion beam sputtering technology, and cathode arc sputtering technology.

4. The method for growing V2O5 nanowires based on phase separation according to claim 1, characterized in that: The substrate is selected from a glass substrate, a silicon substrate or a metal substrate.

5. The method for growing V2O5 nanowires based on phase separation according to claim 3, characterized in that: The steps of preparing a tungsten-vanadium oxide film on a substrate by magnetron sputtering technology specifically include: The tungsten source target, the vanadium source target and the substrate are placed in a vacuum chamber of a magnetron sputtering device, and then a mixed gas of inert gas and oxygen is introduced into the vacuum chamber. The parameters of the magnetron sputtering device are adjusted to perform magnetron sputtering to prepare a tungsten vanadium oxide film on the substrate.

6. The method for growing V2O5 nanowires based on phase separation according to claim 5, characterized in that: The vacuum chamber of the magnetron sputtering equipment is evacuated to 10 -3 -10 -5 Vacuum state of Pa; The pressure of the mixed gas in the vacuum chamber is 0.7-5.0Pa; The parameters of the magnetron sputtering equipment include: the sputtering power of the tungsten source target is 10-100W, the sputtering power of the vanadium source target is 50-200W, and the sputtering time is more than 0.3h.

7. The method for growing V2O5 nanowires based on phase separation according to claim 5, characterized in that: The flow ratio of the inert gas and oxygen is (2-5):

1.

8. The method for growing V2O5 nanowires based on phase separation according to claim 1, characterized in that: The temperature of the annealing treatment is 300°C-600°C.

9. The method for growing V2O5 nanowires based on phase separation according to claim 1, characterized in that: The annealing treatment time is 1h-15h.

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