A method for preparing gallium oxide powder based on liquid gallium

Abstract

The application relates to a preparation method of gallium oxide powder and belongs to the field of semiconductor materials. In a beaker, deionized water and liquid gallium (Ga) are added, ultrasonic dispersion is carried out, and a copper chloride (CuCl2.2H2O) solution is added dropwise under ultrasonic conditions; after reaction, standing and filtration, a colorless transparent solution is obtained. Under the condition of water bath stirring at 60 DEG C, ammonia water (NH3.H2O) is added dropwise into the solution, the pH value is adjusted, white precipitate is obtained, the precipitate is dried and washed, a precursor is obtained, and after calcination at 700-1200 DEG C, beta-Ga2O3 is obtained. The application uses liquid gallium and copper chloride as raw materials, reduces the use of high-purity gallium nitrate in the traditional method, and reduces the cost. Meanwhile, through ammonia water pH value adjustment, gallium oxide powder with uniform morphology and size can be obtained, and the method is simple in operation and short in preparation process.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor materials and relates to a low-cost, short-process method for preparing gallium oxide powder materials. Background Technology

[0002] Gallium oxide (Ga₂O₃) is a typical wide-bandgap semiconductor with a bandgap of Eg = 4.6-4.9 eV. Ga₂O₃ exists in five crystalline phases: α-, β-, γ-, δ-, and ε-Ga₂O₃. Among these five phases, β-Ga₂O₃ is the most stable and has attracted the most attention. Due to its wide bandgap, Ga₂O₃ has become a candidate material for power electronic devices, solar blind zone ultraviolet photodetectors, solar cells, and sensors. Furthermore, Ga₂O₃ is also used in gate dielectrics, field-effect transistors, and Schottky barrier diodes.

[0003] Currently, there are several methods for synthesizing Ga2O3, such as the melt method for preparing single crystals and the vapor deposition method for preparing thin films. In 2022, Shandong University successfully prepared a 4-inch gallium oxide single crystal using the guided-mode method. In 2023, the 46th Research Institute of China Electronics Technology Group Corporation (CETC) prepared a gallium oxide single crystal with a diameter of 15.24 cm using homoepitaxial growth.

[0004] Ga2O3 can also be synthesized chemically, such as through the sol-gel method and the hydrothermal method; these methods are collectively referred to as solution methods. Solution methods are a simple and efficient way to synthesize Ga2O3 powder.

[0005] Zhang Pengyi et al. (CN 103086420 A) provided a method for preparing gallium oxide nanoparticles with high catalytic activity against perfluorocarboxylic acids. Gallium nitrate hydrate was dissolved in water, a surface modifier was added, and then the mixture was calcined at high temperature via water bath heating, hydrothermal treatment, and high-temperature calcination to obtain gallium oxide nanoparticles.

[0006] Kang et al. (CN 111592033A) prepared ellipsoidal gallium oxide with a particle size D50 of 1.5 to 2 μm by simultaneously adding gallium nitrate solution and precipitant (ammonia or sodium hydroxide solution) to the base liquid (precipitant dilution solution) and limiting the reaction temperature, solution concentration, solution feeding rate and type of precipitant.

[0007] Du Bin et al. (CN 114772630 A) proposed a method for preparing micro / nano-structured gallium oxide. Using gallium nitrate as the gallium source and PEG-4000 and DL-aspartic acid as a composite soft template agent, the mixed solution was heated to boiling, and the pH was adjusted to 6, resulting in a sol-gel state. The precursor material was obtained by washing and drying, and then calcined to obtain α-Ga₂O₃ nanomaterials. Summary of the Invention

[0008] This invention provides a low-cost, short-process method for preparing gallium oxide powder, which produces gallium oxide powder with uniform morphology and size distribution.

[0009] The technical solution of this invention is: a method for preparing gallium oxide powder based on liquid gallium metal, comprising the following steps:

[0010] Under ultrasonic conditions, liquid metallic gallium (Ga) is added dropwise to deionized water or anhydrous ethanol, and the ultrasonic time is 10-15 min to obtain a metallic gallium suspension.

[0011] A copper chloride (CuCl2·2H2O) solution was added dropwise to a gallium suspension and reacted under ultrasonic conditions for 15–60 min. The mixture was then allowed to stand and filtered to obtain a clear and transparent solution.

[0012] Place the clear and transparent solution in a water bath at 40–90°C and stir. Add ammonia (NH3·H2O) dropwise to adjust the pH of the solution until a precipitate or gel is obtained. Continue to maintain the water bath conditions and stir for 1–10 hours.

[0013] After standing for 1 hour, the mixture was allowed to cool naturally to room temperature. The precipitate was then filtered and washed three times each with deionized water and anhydrous ethanol. Finally, the precipitate was vacuum dried at 80°C for 8 hours to obtain the precursor.

[0014] The precursor was placed in an alumina crucible and calcined in a muffle furnace at 700–1200 °C for 5 h to obtain β-Ga2O3.

[0015] Furthermore, the volume ratio of metallic gallium to deionized water or anhydrous ethanol is (0.1–10):100.

[0016] Furthermore, the volume ratio of the gallium suspension to the copper chloride solution is 1:1, the molar ratio of gallium to copper chloride is (1.5–3):1, and the concentration of the copper chloride solution is 0.05–1 mol / L.

[0017] Furthermore, the pH value is controlled between 3.5 and 10, the precursor is stirred in a water bath for 1 to 10 hours, the calcination temperature is 700 to 1200℃, and the calcination time is greater than 5 hours.

[0018] The advantages of this invention are its simple preparation process, short procedure, and low cost. Using liquid gallium metal and copper chloride as raw materials avoids the use of gallium nitrate in conventional synthesis methods, thus reducing preparation costs. By adjusting the pH value with ammonia, rod-shaped gallium oxide powder with uniform morphology and size can be obtained. Attached Figure Description

[0019] Figure 1 Scanning electron microscope image of the rod-shaped gallium oxide powder material prepared in this invention.

[0020] Figure 2X-ray diffraction pattern of the powder material prepared by this invention. Detailed Implementation

[0021] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0022] Example 1

[0023] Take 400 μL of liquid metallic gallium and disperse it in 50 ml of deionized water by ultrasonication to obtain a gallium suspension; weigh 7.67 g of copper chloride dihydrate (CuCl2·2H2O) and dissolve it in 50 ml of deionized water to obtain a 0.9 mol / L copper chloride solution;

[0024] Copper chloride solution was gradually added dropwise to gallium suspension under ultrasonic conditions, and the reaction was carried out under ultrasonic conditions for 15 minutes. Then, the solution was allowed to stand and filtered to obtain a clear and transparent solution.

[0025] Ammonia was added dropwise to the clear, transparent solution under stirring in a 60°C water bath to adjust the pH to 8, resulting in a white precipitate. The 60°C water bath conditions were maintained and stirred for 2 hours.

[0026] After standing for 1 hour, the mixture was allowed to cool naturally to room temperature. The precipitate was then filtered and washed three times each with deionized water and anhydrous ethanol. Finally, the precipitate was vacuum dried at 80°C for 8 hours to obtain the precursor.

[0027] The precursor was placed in an alumina crucible and placed in a muffle furnace, and calcined at 800℃ for 5 hours to obtain β-Ga2O3 powder.

[0028] The above process was used to prepare the following... Figure 1 The image shows rod-shaped gallium oxide powder material. The material's size is on the micrometer scale, approximately 3 μm long and 1 μm in diameter. The rod-shaped particles are composed of even smaller lamellar structures. The material exhibits uniform morphology and size distribution, and its crystal structure is monoclinic β-Ga₂O₃. Figure 2 As shown.

[0029] Example 2

[0030] The conditions are the same as in Example 1, except that in step 3, ammonia is used to adjust the pH to 6.

[0031] Rod-shaped gallium oxide powder material was prepared through the above steps. Compared with Example 1, the powder size was reduced, with a length of approximately 1 μm and a diameter of approximately 0.3 μm. The surface of the rod-shaped particles was smooth, and no plate-like structure was observed.

[0032] Example 3

[0033] The conditions are the same as in Example 1, except that the water bath stirring time in step 3 is extended to 6 hours.

[0034] Rod-shaped gallium oxide powder material was prepared through the above steps. Compared with Example 1, by extending the stirring time, the gallium oxide particles became more slender, with a length of approximately 5 μm and a diameter of approximately 0.8 μm.

[0035] Example 4

[0036] The conditions are the same as in Example 1, except that the calcination temperature in step 5 is 1000°C.

[0037] Rod-shaped gallium oxide powder was prepared through the above steps. Compared with Example 1, increasing the calcination temperature did not significantly change the morphology and size of the gallium oxide. The powder remained micrometer-sized, approximately 3 μm long and 1 μm in diameter.

[0038] Example 5

[0039] The conditions were the same as in Example 1, except that in step 1, 400 μL of liquid gallium metal and 7.67 g of copper chloride dihydrate (CuCl2·2H2O) were dissolved in 75 ml of deionized water, respectively, so that the concentration of the copper chloride solution was 0.6 mol / L, and it was used for the preparation of the material.

[0040] Rod-shaped gallium oxide powder material was prepared through the above steps. Compared with Example 1, the concentration of copper chloride solution was reduced, and the resulting gallium oxide particles were still uniform rod-shaped. However, the size was reduced, with a length of about 2 μm and a diameter of 0.7 μm.

Claims

1. A method for preparing gallium oxide powder based on liquid gallium metal, characterized in that, The steps include the following: Under ultrasonic conditions, liquid metallic gallium (Ga) is added dropwise to deionized water or anhydrous ethanol, and the ultrasonic time is 10-15 min to obtain a metallic gallium suspension. A copper chloride solution (CuCl2·2H2O) was added dropwise to a gallium suspension and reacted under ultrasonic conditions for 15–60 min. The mixture was then allowed to stand and filtered to obtain a clear and transparent solution. Place the clear and transparent solution in a water bath at 40–90°C and stir. Add ammonia (NH3·H2O) dropwise to adjust the pH of the solution until a precipitate or gel is obtained. Continue to maintain the water bath conditions and stir for 1–10 hours. After standing for 1 hour, the mixture was allowed to cool naturally to room temperature. The precipitate was then filtered and washed three times each with deionized water and anhydrous ethanol. Finally, the precursor was vacuum dried at 80°C for 8 hours. The precursor was placed in an alumina crucible and calcined in a muffle furnace at 700–1200 °C for 5 h to obtain β-Ga2O3.

2. The method for preparing gallium oxide powder based on liquid gallium metal as described in claim 1, characterized in that, The dispersion medium for liquid gallium metal is deionized water or anhydrous ethanol, and the temperature is controlled between 30 and 40°C.

3. The method for preparing gallium oxide powder based on liquid gallium metal as described in claim 1, characterized in that, The volume ratio of gallium suspension to copper chloride solution is 1:1, the molar ratio of gallium to copper chloride is 1.5 to 3:1, and the concentration of copper chloride solution is 0.05 to 1 mol / L.

4. The method for preparing gallium oxide powder based on liquid gallium metal as described in claim 1, characterized in that, The pH value should be controlled between 3.5 and 10.

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