Preparation method of gallium oxide nano material

Abstract

The invention discloses a method for synthesizing GaOOH and beta-Ga2O3 materials with relatively good crystal quality and relatively uniform phase by taking gallium nitrate as a gallium source through a hydrothermal method and high-temperature calcination treatment, and characterizing the GaOOH and beta-Ga2O3 materials. The hydrothermal method adopted by the method has the advantages of simplicity in operation, low cost and the like, and has great advantages in the aspect of synthesizing gallium oxide. And compared with the traditional methods such as CVD (Chemical Vapor Deposition) and the like, which need to introduce noble metal elements as catalysts, easily cause reduction of material crystal quality and introduce unnecessary impurity elements, the method disclosed by the invention can be used for synthesizing the gallium oxide material with relatively good crystal quality and relatively uniform phase by combining a hydrothermal method and high-temperature calcination treatment. GaOOH powder is synthesized by adding an anionic surfactant sodium dodecyl benzene sulfonate (SDBS) solution with different concentrations, and then the GaOOH powder is calcined at the high temperature of 900 DEG C to obtain beta-Ga2O3 materials with different sizes.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation and development of Ga2O3 materials with high crystal quality and controllable size and morphology and the research on their related optical properties, and particularly relates to a preparation method of gallium oxide nanomaterials. Background Art

[0002] In recent years, compound semiconductor materials of elemental gallium have been widely used in the fields of electronics, optoelectronics, electrochemistry, etc. As a new type of ultra-wide bandgap semiconductor material, gallium oxide has received extensive attention in the semiconductor field. Compared with the currently common wide bandgap semiconductors SiC and GaN, Ga2O3 has a larger Baliga figure of merit and a lower expected growth cost, and is more promising in high-voltage, high-power, high-efficiency, and small-volume electronic devices. In the future, gallium oxide devices may become power electronic devices that directly compete with silicon carbide.

[0003] Gallium oxide has six crystal forms, namely α, β, γ, δ, ε, and κ. Among them, β-Ga2O3 has a monoclinic crystal structure and is the thermodynamically stable form. The formation of other metastable phases depends on the lattice structure of the substrate and the growth temperature, and it is easy to transform into β-Ga2O3 at high temperatures. Therefore, most of the current research work on gallium oxide is carried out based on β-Ga2O3.

[0004] At present, β-Ga2O3 nanomaterials with different morphologies have been reported, such as nanowires, nanosheets, nanobelts, nanorods, and nanotubes, etc. How to prepare β-Ga2O3 nanomaterials with controllable size and good crystallinity has become one of the current research hotspots. However, traditional methods such as CVD need to introduce precious metal elements as catalysts, which easily lead to a decrease in the crystal quality of the material and the introduction of unnecessary impurity elements. In contrast, the hydrothermal method for preparing nanomaterials has the advantages of simple operation, low cost, good crystal quality, and uniform phase formation. Summary of the Invention

[0005] The present invention uses gallium nitrate as the gallium source and synthesizes pure-phase β-Ga2O3 by the hydrothermal method, which has the characteristics of simple and convenient operation and low energy consumption, and has great advantages in the synthesis of gallium oxide. On this basis, by combining the hydrothermal method and high-temperature calcination treatment, β-Ga2O3 materials with different sizes are prepared by adjusting the pH value of the precursor solution and the concentration of the anionic surfactant sodium dodecylbenzenesulfonate (SDBS).

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A preparation method of gallium oxide nanomaterials, comprising the following steps:

[0008] 1) Using gallium nitrate as the gallium source, dissolve it in ultrapure water, add sodium dodecylbenzenesulfonate (SDBS), stir evenly, add a precipitant to adjust the pH value of the solution, then transfer it to a Teflon inner liner and place it in a reaction kettle, and carry out a hydrothermal reaction in an oven. After the reaction is completed, a liquid containing GaOOH is obtained;

[0009] 2) Load the liquid containing GaOOH obtained in step 1) into a centrifuge tube for centrifugation, wash it with ultrapure water, pour out the supernatant, repeat the washing and centrifugation three times, and place it in an oven for drying to obtain GaOOH powder;

[0010] 3) Put the GaOOH powder obtained in step 2) into a muffle furnace for calcination, and cool it to room temperature to obtain β-Ga2O3 nanomaterials.

[0011] Furthermore, in the above preparation method, in step 1), the gallium nitrate is Ga(NO3)3·xH2O with a purity of 99.99%.

[0012] Even further, in the above preparation method, in step 1), the concentration of the gallium nitrate in ultrapure water is 0.2 mol / L.

[0013] Furthermore, in the above preparation method, in step 1), the concentration of the SDBS in ultrapure water is 0.8 - 3 mmol / L.

[0014] Furthermore, in the above preparation method, in step 1), the precipitant is ammonia water with a volume ratio of 1:1.

[0015] Furthermore, in the above preparation method, in step 1), adjust the pH of the solution to 8.

[0016] Furthermore, in the above preparation method, in step 1), the hydrothermal reaction temperature is 180 °C and the hydrothermal reaction time is 22 h.

[0017] Furthermore, in the above preparation method, in step 2), the drying conditions are: drying at 60 °C for 10 h.

[0018] Furthermore, in the above preparation method, in step 3), the calcination conditions are: calcination at 900 °C for 3 h.

[0019] The beneficial effects of the present invention are:

[0020] 1. The present invention uses gallium nitrate as the gallium source, synthesizes β-Ga2O3 by the hydrothermal method, and characterizes and analyzes it. The hydrothermal method has the advantages of simple operation and low cost, and has great advantages in the synthesis of gallium oxide.

[0021] 2. The present invention abandons the introduction of a seed layer in the traditional preparation method and directly realizes the controllable synthesis of GaOOH nanomaterials by optimizing the reaction system. This process significantly simplifies the preparation process, and at the same time, the obtained nano-powder products have excellent morphological uniformity and high purity, which are particularly suitable for the industrial preparation of GaOOH and β-Ga2O3 targets, showing broad commercial application prospects in the field of optoelectronic functional materials.

[0022] 3. The present invention particularly selects the anionic surfactant sodium dodecylbenzenesulfonate (SDBS) as a morphology regulator. By adjusting the addition concentration of SDBS (preferably 0.8 - 3 mmol / L), the size and morphological characteristics of the obtained nanomaterials can be controlled. This technology provides an effective means for obtaining GaOOH and β-Ga2O3 nanomaterials with specific performance requirements.

[0023] In summary, the present invention provides a method for preparing GaOOH and β-Ga2O3 nanomaterials based on the hydrothermal method. Using gallium nitrate hydrate as the gallium source, the phase transformation from GaOOH to β-Ga2O3 is realized through precursor solution preparation, centrifugal purification, hydrothermal reaction, and controllable heat treatment processes. In particular, by introducing sodium dodecylbenzenesulfonate (SDBS) as a morphology regulator, the size and morphological characteristics of the product can be controlled. This method has a simple process, low cost, and can conveniently prepare two different products in the same process, showing significant industrial application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a process flow chart for the hydrothermal synthesis of GaOOH and β-Ga2O3.

[0025] Figure 2 It is an X-ray diffraction (XRD) pattern of GaOOH nanomaterials.

[0026] Figure 3 It is an X-ray diffraction (XRD) pattern of β-Ga2O3 nanomaterials.

[0027] Figure 4 It is a scanning electron microscope (SEM) image of GaOOH nanomaterials.

[0028] Figure 5 It is a scanning electron microscope (SEM) image of β-Ga2O3 nanomaterials. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following further elaborates the present invention through specific embodiments, but does not limit the present invention.

[0030] Example 1

[0031] A preparation method for preparing β-Ga2O3 nanomaterials by the hydrothermal method (such asFigure 1 ) includes the following steps:

[0032] Clean the experimental utensils, and ultrasonically clean the experimental utensils with absolute ethanol and ultrapure water. The experimental utensils include beakers, glass rods, test tubes, reaction kettles, etc. Use gallium nitrate hydrate (Ga(NO3)3·xH2O (99.9%)) as the gallium source. Specifically, weigh 2.5573 g of Ga(NO3)3·xH2O (99.99%) with a balance and add it to 50 mL of ultrapure water. Stir at room temperature until dissolved to form a uniformly transparent solution. Add sodium dodecylbenzenesulfonate (SDBS) according to the concentration (0.8, 1.5, 3.0 mmol / L), and stir evenly to obtain a precursor solution. Then add 1:1 ammonia water dropwise, adjust the pH to 8 and keep it unchanged. Transfer the solution to a Teflon inner liner and then load it into a reaction kettle. Carry out hydrothermal reaction in an oven at 180 °C for 22 h. After the reaction is completed, load the solution into a centrifuge tube, wash and centrifuge it with ultrapure water, pour out the supernatant, repeat the washing and centrifugation three times, and place it in an oven at 60 °C to dry for 10 hours to obtain GaOOH powder.

[0033] Put the prepared GaOOH powder into a muffle furnace, calcine it at 900 °C for 3 h, and naturally cool it to room temperature to obtain β-Ga2O3 nanomaterials.

[0034] Example 2

[0035] A preparation method for preparing β-Ga2O3 nanomaterials by hydrothermal method (as Figure 1 ) includes the following steps:

[0036] Clean the experimental utensils, and ultrasonically clean the experimental utensils with absolute ethanol and ultrapure water. The experimental utensils include beakers, glass rods, test tubes, reaction kettles, etc. Use gallium nitrate hydrate (Ga(NO3)3·xH2O (99.9%)) as the gallium source. Specifically, weigh 2.5573 g of Ga(NO3)3·xH2O (99.99%) with a balance and add it to 50 mL of ultrapure water. Stir at room temperature until dissolved to form a uniformly transparent solution. Add sodium dodecylbenzenesulfonate (SDBS) at a concentration of 1.50 mmol / L, and stir evenly to obtain a precursor solution. Then add 1:1 ammonia water dropwise, adjust the pH to 8 and keep it unchanged. Transfer the solution to a Teflon inner liner and then load it into a reaction kettle. Carry out hydrothermal reaction in an oven at 180 °C for 22 h. After the reaction is completed, load the solution into a centrifuge tube, wash and centrifuge it with ultrapure water, pour out the supernatant, repeat the washing and centrifugation three times, and place it in an oven at 60 °C to dry for 10 hours to obtain GaOOH powder.

[0037] Put the prepared GaOOH powder into a muffle furnace, calcine it at 900 °C for 3 h, and naturally cool it to room temperature to obtain β-Ga2O3 nanomaterials.

[0038] Example 3

[0039] A preparation method for preparing β-Ga2O3 nanomaterials by hydrothermal method (as Figure 1 ), including the following steps:

[0040] Clean the experimental equipment, and ultrasonically clean the experimental equipment with anhydrous ethanol and ultrapure water. The experimental equipment includes beakers, glass rods, test tubes, reaction kettles, etc. Use gallium nitrate hydrate (Ga(NO3)3·xH2O(99.9%)) as the gallium source. Specifically, weigh 2.5573 g of Ga(NO3)3·xH2O(99.99%) with a balance and add it to 50 mL of ultrapure water, stir at room temperature until dissolved to form a uniform and transparent solution, add sodium dodecylbenzenesulfonate (SDBS) at a concentration of 3.0 mmol / L, and stir evenly to obtain a precursor solution. Then add 1:1 ammonia water dropwise, adjust the pH to 8 and keep it unchanged, transfer the solution to a Teflon inner liner and then put it into a reaction kettle, carry out hydrothermal reaction in an oven at 180 °C for 22 h. After the reaction, transfer the solution into a centrifuge tube, wash and centrifuge it with ultrapure water, pour out the supernatant, repeat the washing and centrifugation three times, and dry it in an oven at 60 °C for 10 hours to obtain GaOOH powder.

[0041] Put the prepared GaOOH powder into a muffle furnace, calcine it at 900 °C for 3 h, and naturally cool it to room temperature to obtain β-Ga2O3 nanomaterials.

[0042] Figure 2 and Figure 3 are the X-ray diffraction (XRD) patterns of the GaOOH and β-Ga2O3 nanomaterials prepared in Examples 1-3 respectively. The main peaks in the figure correspond to the β-phase of the GaOOH and Ga2O3 materials respectively, and it can be judged that the nanomaterials are GaOOH and β-Ga2O3 powder materials respectively.

[0043] Figure 4 and Figure 5 are the scanning electron microscopy (SEM) images of the GaOOH and β-Ga2O3 nanomaterials prepared in Examples 1-3 respectively. In the SEM images, it can be observed that with the increase of the SDBS concentration, the sizes of GaOOH and β-Ga2O3 increase.

[0044] It should be noted that this embodiment only gives a demonstration of the present invention, and its specific parameters are not limited by the embodiment.

Claims

1. A method for preparing a gallium oxide nanomaterial, characterized in that: The steps include: 1) Gallium nitrate is used as a gallium source, dissolved in ultrapure water, sodium dodecylbenzene sulfonate SDBS is added, stirred evenly, a precipitant is added to adjust the pH value of the solution, and then the solution is transferred to a Teflon liner and loaded into a reactor, and a hydrothermal reaction is carried out in an oven. After the reaction is completed, a liquid containing GaOOH is obtained; 2) putting the GaOOH-containing liquid obtained in step 1) into a centrifuge tube for centrifugation, washing with ultrapure water, pouring out the supernatant, repeating the washing and centrifugation three times, and drying in an oven to obtain GaOOH powder; 3) The GaOOH powder obtained in step 2) is placed in a muffle furnace for calcination, and cooled to room temperature to obtain β-Ga2O3 nanomaterials.

2. The preparation method according to claim 1, characterized in that: In step 1), the gallium nitrate is Ga(NO3)3·xH2O with a purity of 99.99%.

3. The preparation method according to claim 2, characterized in that: In step 1), the concentration of gallium nitrate in ultrapure water is 0.2 mol / L.

4. The preparation method according to claim 1, characterized in that: In step 1), the concentration of SDBS in ultrapure water is 0.8-3 mmol / L.

5. The preparation method according to claim 1, characterized in that: In step 1), the precipitant is aqueous ammonia in a volume ratio of 1:

1.

6. The preparation method according to claim 1, characterized in that: In step 1), the solution pH is adjusted to 8.

7. The preparation method according to claim 1, characterized in that: In step 1), the hydrothermal reaction temperature is 180° C. and the hydrothermal reaction time is 22 h.

8. The preparation method according to claim 1, characterized in that: In step 2), the drying condition is: drying at 60° C. for 10 h.

9. The preparation method according to claim 1, characterized in that: In step 3), the calcination conditions are: calcination at 900° C. for 3 h.

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