Method for preparing gallium oxide powder based on liquid metal gallium

Abstract

The invention relates to a preparation method of gallium oxide powder, and belongs to the field of semiconductor materials. The preparation method comprises the following steps: adding deionized water and liquid metal gallium (Ga) into a beaker, carrying out ultrasonic dispersion, dropwise adding a copper chloride (CuCl2. 2H2O) solution under an ultrasonic condition, standing after the reaction is completed, and filtering to obtain a colorless transparent solution; dropwise adding ammonia water (NH3.H2O) into the solution under the water bath stirring condition of 60 DEG C, adjusting the pH value to obtain white precipitate, drying the precipitate, washing to obtain a precursor, and calcining at the temperature of 700-1200 DEG C to obtain beta-Ga2O3; according to the method, liquid metal gallium and copper chloride are used as raw materials, so that the use of high-purity gallium nitrate in a traditional method is reduced, and the cost is reduced. Meanwhile, the gallium oxide powder with uniform morphology and size can be obtained by adjusting the pH value through ammonia water, and the method is simple and convenient to operate and short in preparation process.

Description

Technical Field

[0001] The invention belongs to the field of semiconductor materials and relates to a method for preparing a gallium oxide powder material with low cost and short process. Background Art

[0002] Gallium oxide (Ga2O3) is a typical wide bandgap semiconductor with a bandgap width of E g =4.6-4.9 eV. There are five crystalline phases of Ga2O3: α-, β-, γ-, δ- and ε-Ga2O3. Among these five crystalline phases, β-Ga2O3, as the most stable phase, attracts the most attention. Due to the wide band gap of Ga2O3, it has become a candidate material for power electronic devices, solar blind zone ultraviolet photodetectors, solar cells and sensors. In addition, Ga2O3 is also used in gate dielectrics, field effect transistors and Schottky barrier diodes.

[0003] There are currently many methods for synthesizing Ga2O3, such as preparing single crystals by melt method and preparing thin films by vapor deposition method. In 2022, Shandong University successfully prepared a 4-inch gallium oxide single crystal by guided mold method. In 2023, China Electronics Technology Group Corporation 46th Institute prepared a gallium oxide single crystal with a diameter of 15.24 cm by homoepitaxial growth.

[0004] Ga2O3 can also be synthesized by chemical methods, such as sol-gel method and hydrothermal method, which are collectively referred to as solution method. Solution method is a simple and efficient method for synthesizing Ga2O3 powder.

[0005] Zhang Pengyi et al. (CN 103086420 A) provide a method for preparing nano-gallium oxide with high catalytic activity for perfluorocarboxylic acid substances. Gallium nitrate hydrate is dissolved in water, a surface modifier is added, and then the nano-gallium oxide is obtained by water bath heating, hydrothermal heating, and high-temperature calcination.

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

[0007] Du Bin et al. (CN 114772630 A) proposed a method for preparing micro-nanostructured gallium oxide. Gallium nitrate was used as a gallium source, PEG-4000 and DL-aspartic acid were used as composite soft templates, the mixed solution was heated to boiling, the pH value of the solution was adjusted to 6, and the system was in a sol state; the precursor material was washed and dried; and the α-Ga2O3 nanomaterial was calcined. Summary of the invention

[0008] The invention provides a method for preparing gallium oxide powder with low cost and short process. The prepared gallium oxide powder has uniform morphology and size distribution.

[0009] The technical solution of the present invention is: a method for preparing gallium oxide powder based on liquid metal gallium, comprising the following steps: Under ultrasonic conditions, liquid metal gallium (Ga) is added dropwise to deionized water or anhydrous ethanol for 10 to 15 minutes to obtain a metal gallium suspension; The copper chloride (CuCl2·2H2O) solution was added dropwise to the gallium suspension and reacted for 15-60 min under ultrasonic conditions, then allowed to stand and filtered to obtain a clear and transparent solution; Place the clear transparent solution in a water bath at 40-90℃ and stir, add ammonia (NH3·H2O) to adjust the pH value of the solution until a precipitate or gel is obtained, continue to maintain the water bath condition, and stir for 1-10 hours; The mixture was allowed to stand for 1 h, cooled naturally to room temperature, and then filtered to obtain the precipitate, which was washed with deionized water and anhydrous ethanol three times respectively, and finally dried under vacuum at 80 °C for 8 h to obtain the precursor; The precursor was loaded into a corundum crucible and placed in a muffle furnace, and calcined at 700-1200°C for 5h to obtain β-Ga2O3.

[0010] Furthermore, the volume ratio of metallic gallium to deionized water or anhydrous ethanol is (0.1-10):100.

[0011] Furthermore, the volume ratio of the metal gallium suspension and 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.

[0012] Furthermore, the pH value is controlled at 3.5-10, the precursor water bath stirring time is 1-10 hours, the calcination temperature is 700-1200° C., and the calcination time is greater than 5 hours.

[0013] The invention has the advantages of simple preparation process, short flow and low cost. Liquid metal gallium and copper chloride are used as raw materials, avoiding the use of gallium nitrate in conventional synthesis methods, and reducing preparation costs. The pH value is regulated by ammonia water to obtain rod-shaped gallium oxide powder with uniform morphology and size. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 . Scanning electron microscope image of the rod-shaped gallium oxide powder material prepared by the present invention.

[0015] Figure 2 . X-ray diffraction pattern of the powder material prepared by the present invention. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only intended to illustrate the present invention and are not intended to limit the scope of the present invention. Those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application. Example

[0017] 400 μL of liquid metal gallium was ultrasonically dispersed in 50 ml of deionized water to obtain a gallium suspension; 7.67 g of copper chloride dihydrate (CuCl2·2H2O) was weighed and dissolved in 50 ml of deionized water to obtain a 0.9 mol / L copper chloride solution; The copper chloride solution was gradually dropped into the gallium suspension under ultrasonic conditions, and the reaction was carried out under ultrasonic conditions for 15 minutes, and then allowed to stand and filtered to obtain a clear and transparent solution; Add ammonia water dropwise to the clear transparent solution under stirring conditions at 60°C in a water bath to adjust the pH value to 8 to obtain a white precipitate; continue to maintain the water bath conditions at 60°C and stir for 2 hours; The mixture was allowed to stand for 1 h, cooled naturally to room temperature, and then filtered to obtain the precipitate, which was washed with deionized water and anhydrous ethanol three times respectively, and finally dried under vacuum at 80 °C for 8 h to obtain the precursor; The precursor was placed in a corundum crucible in a muffle furnace and calcined at 800°C for 5 hours to obtain β-Ga2O3 powder.

[0018] The above process prepared Figure 1 The rod-shaped gallium oxide powder material shown in the figure is micron-sized, about 3 μm long and about 1 μm in diameter. The rod-shaped particles are composed of smaller lamellar structures. The morphology and size distribution of the material are uniform, and its crystal structure is monoclinic β-Ga2O3, such as Figure 2 shown. Example

[0019] The conditions are the same as those in Example 1, except that ammonia water is used in step 3 to adjust the pH value to 6.

[0020] The above steps are used to prepare a rod-shaped gallium oxide powder material. Compared with Example 1, the powder size is reduced, with a length of about 1 μm and a diameter of about 0.3 μm. The surface of the rod-shaped particles is smooth without a flaky structure. Example

[0021] The conditions are the same as those in Example 1, except that the water bath stirring time in step 3 is extended to 6 h.

[0022] 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 about 5 μm and a diameter of about 0.8 μm. Example

[0023] The conditions are the same as those in Example 1, except that the calcination temperature in step 5 is 1000°C.

[0024] Rod-shaped gallium oxide powder material was prepared through the above steps. Compared with Example 1, the morphology and size of gallium oxide did not change significantly when the calcination temperature was increased. The powder was still micron-sized, about 3 μm long and about 1 μm in diameter. Example

[0025] The conditions are the same as those in Example 1, except that in step 1, 400 μL of liquid metal gallium and 7.67 g of dihydrate copper chloride (CuCl2·2H2O) are respectively dissolved in 75 ml of deionized water, that is, the concentration of the copper chloride solution is 0.6 mol / L, and used for the preparation of the material.

[0026] The above steps prepared a rod-shaped gallium oxide powder material. Compared with Example 1, the concentration of the copper chloride solution was reduced, and the obtained gallium oxide particles were still uniformly rod-shaped, but the size was reduced to about 2 μm in length and 0.7 μm in diameter.

Claims

1. A method for preparing gallium oxide powder based on liquid metal gallium, characterized in that: The steps include: Under ultrasonic conditions, liquid metal gallium (Ga) is added dropwise to deionized water or anhydrous ethanol for 10 to 15 minutes to obtain a metal gallium suspension; The copper chloride (CuCl2·2H2O) solution was added dropwise to the gallium suspension and reacted for 15-60 min under ultrasonic conditions, then allowed to stand and filtered to obtain a clear and transparent solution; Place the clear transparent solution in a water bath at 40-90℃ and stir, add ammonia (NH3·H2O) to adjust the pH value of the solution until a precipitate or gel is obtained, continue to maintain the water bath condition, and stir for 1-10 hours; The mixture was allowed to stand for 1 h, cooled naturally to room temperature, and then filtered to obtain the precipitate, which was washed three times with deionized water and three times with anhydrous ethanol, and finally dried under vacuum at 80 °C for 8 h to obtain the precursor. The precursor was loaded into a corundum crucible and placed in a muffle furnace, and calcined at 700-1200°C for 5h to obtain β-Ga2O3.

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

3. A method for preparing gallium oxide powder based on liquid metal gallium according to claim 1, characterized in that: The volume ratio of the metal gallium suspension and 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.

4. The method for preparing gallium oxide powder based on liquid metal gallium according to claim 1, characterized in that: The pH value is controlled at 3.5-10, the precursor water bath stirring time is 1-10 hours, the calcination temperature is 700-1200°C, and the calcination time is greater than 5 hours.

Images