A method for preparing BiZn2VO6 microwave dielectric ceramic powder at low temperature

Abstract

This invention provides a method for preparing BiZn₂VO₆ microwave dielectric ceramic powder at low temperature, belonging to the field of inorganic non-metallic material preparation technology. Using Bi(NO₃)₃·5H₂O, Zn(NO₃)₂·6H₂O, and NH₄VO₃ as raw materials, the raw materials are first dissolved in water to form two solutions. Then, the two solutions are mixed, and the pH value is adjusted to obtain a Bi-Zn-V precipitate. Finally, the precipitate is washed, dried, and calcined at a certain temperature to obtain BiZn₂VO₆ powder. This invention, through specific raw material composition and preparation route, can prepare high-purity powder under low-temperature and short-time conditions, and the obtained powder particles have small particle size and uniform distribution, showing good application prospects.

Description

Technical Field

[0001] This invention belongs to the field of inorganic non-metallic material preparation technology, specifically relating to a method for preparing BiZn2VO6 microwave dielectric ceramic powder at low temperature. Background Technology

[0002] Microwave dielectric ceramics refer to ceramics used in microwave frequency bands (300MHz~300GHz) circuits as dielectric materials to perform specific functions. They play an important role in energy storage, dielectric waveguides, dielectric resonance, and insulation support of devices in microwave circuits. Microwave dielectric ceramics are key materials for microwave components used in modern communication equipment, such as filters, resonators, dielectric substrates, and multilayer ceramic capacitors (MLCCs). They have significant application value in many fields, including civilian communications, military communications, wireless local area networks (WLANs), and global positioning systems (GPS). As mobile terminals gradually iterate towards portability and multifunctionality, higher requirements are placed on the integration of electronic products. In electronic products, passive components occupy up to 90% of the volume; therefore, the miniaturization of passive components is the key to the integration of electronic products. Solving this problem requires the support of low-temperature co-fired ceramic (LTCC) technology. BiZn₂VO₆ is a vanadate-based microwave dielectric ceramic material. In the paper "A novel low-firing BiZn₂VO₆ microwave dielectric ceramic with low loss," ceramic powder was prepared using a conventional solid-state method. All raw materials were ball-milled for 6 hours, followed by calcination at 720℃ for 4 hours, and its potential as a candidate material for LTCC technology was reported. In the paper "Ultralow temperature cofired BiZn₂VO₆ dielectric ceramics doped with B₂O₃ and Li₂CO₃ for ULTCC applications," ceramic powder was prepared using a conventional solid-state method. All raw materials were ball-milled for 4 hours, followed by calcination at 780℃ for 4 hours, and its potential as a candidate material for ULTCC technology was reported.

[0003] Currently, most scientific research and industrial production use traditional solid-state methods to prepare ceramic powders. However, this method, based on mechanical grinding and mixing, typically involves high energy consumption and produces powder particles that are generally large and uneven in size, which is detrimental to low-temperature sintering of ceramics. This patent employs a co-precipitation method to prepare BiZn₂VO₆ ceramic powder. This preparation technology is based on chemical mixing of raw materials, resulting in a homogeneous precipitate mixture as the calcination precursor. This allows for a higher level of mixing of the raw materials, which is beneficial for calcination to a pure phase and can reduce the heat treatment temperature and time of the powder to some extent. This invention uses a novel approach to prepare high-purity BiZn₂VO₆ ceramic powder. Compared to traditional methods, it has advantages such as lower preparation temperature and shorter calcination time, resulting in powder particles with small size and uniform distribution. Summary of the Invention

[0004] The purpose of this invention is to provide a new technical route for preparing BiZn2VO6 microwave dielectric ceramic powder, which can effectively solve the problems of high preparation temperature, long preparation time and large particle size in the existing technology.

[0005] The technical solution of this invention is as follows:

[0006] A method for preparing BiZn2VO6 microwave dielectric ceramic powder at low temperature, comprising the following steps:

[0007] (1) Weigh out Bi(NO3)3·5H2O, Zn(NO3)2·6H2O and NH4VO3 in a molar ratio of 1:2:1 as raw materials;

[0008] (2) Add the NH4VO3 weighed in step (1) to water and stir continuously in a water bath at 80°C until completely dissolved, with a concentration of 0.05-0.07 mol / L;

[0009] (3) Add the Bi(NO3)3·5H2O and Zn(NO3)2·6H2O weighed in step (1) to water, add nitric acid dropwise and stir continuously until completely dissolved; wherein Bi 3+ The concentration is 0.08-0.11 mol / L, Zn 2+ The concentration was 0.16-0.22 mol / L;

[0010] (4) After mixing the solutions obtained in steps (2) and (3), adjust the pH of the solution to 7.0-8.0 with ammonia water, and stir continuously at room temperature for 1-2 hours until the reaction is complete. Then let it stand for a period of time to allow the precipitate to settle naturally.

[0011] (5) The precipitate obtained in step (4) is washed by vacuum filtration. After washing, the precipitate is transferred to an oven and dried at 120°C for 3-5 hours to obtain precursor powder.

[0012] (6) Transfer the precursor powder obtained in step (5) to a muffle furnace and calcine it at 700-800℃ for 1-4 hours to obtain BiZn2VO6 material.

[0013] The beneficial effects of this invention are:

[0014] (1) The present invention adopts a new preparation method, which can prepare BiZn2VO6 material by calcination at a low temperature of 700℃ for a short time of 1h. Compared with the high temperature solid phase method, the preparation temperature is reduced and the preparation time is shortened, which effectively reduces production energy consumption.

[0015] (2) The prepared BiZn2VO6 material has uniform particles and small particle size, which is beneficial for subsequent sintering and easy for subsequent industrial applications. Attached Figure Description

[0016] Figure 1 The images show the XRD patterns of BiZn2VO6 ceramic powders prepared in Examples 1-3. Wherein, a represents Example 3, b represents Example 1, and c represents Example 2.

[0017] Figure 2 The images show the XRD patterns of the BiZn2VO6 ceramic powders prepared in Examples 4-5. Where e represents Example 4 and f represents Example 5.

[0018] Figure 3 The image shows a SEM image of the BiZn2VO6 ceramic powder prepared in Example 1. Detailed Implementation

[0019] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the present invention is not limited to the following embodiments.

[0020] Example 1

[0021] Bi(NO3)3·5H2O, Zn(NO3)2·6H2O, and NH4VO3 were weighed out according to a stoichiometric ratio of 1:2:1. NH4VO3 was dissolved in deionized water at 80℃ to obtain a pale yellow solution A with a concentration of 0.07 mol / L. Bi(NO3)3·5H2O and Zn(NO3)2·6H2O were added to deionized water, and nitric acid was added dropwise until completely dissolved to obtain a colorless solution B. Bi... 3+ The concentration of Zn is 0.11 mol / L. 2+The concentration was 0.22 mol / L. Solution A was mixed with solution B, and the pH was adjusted to 8.0 using ammonia. The mixture was stirred continuously at room temperature for 1 hour until the reaction was complete, and then allowed to stand for a period of time to allow the precipitate to settle naturally. The precipitate was washed by vacuum filtration, and then transferred to an oven and dried at 120℃ for 5 hours to obtain a light yellow Bi-Zn-V precursor powder. The precursor powder was transferred to a muffle furnace and calcined in air at 700℃ for 2 hours. After cooling to room temperature, BiZn2VO6 material was obtained.

[0022] Example 2

[0023] The difference between this embodiment and Example 1 is that the calcination time is 1 hour. The specific preparation method is as follows:

[0024] Bi(NO3)3·5H2O, Zn(NO3)2·6H2O, and NH4VO3 were weighed out according to a stoichiometric ratio of 1:2:1. NH4VO3 was dissolved in deionized water at 80℃ to obtain a pale yellow solution A with a concentration of 0.07 mol / L. Bi(NO3)3·5H2O and Zn(NO3)2·6H2O were added to deionized water, and nitric acid was added dropwise until completely dissolved to obtain a colorless solution B. Bi... 3+ The concentration of Zn is 0.11 mol / L. 2+ The concentration was 0.22 mol / L. Solution A was mixed with solution B, and the pH was adjusted to 8.0 using ammonia. The mixture was stirred continuously at room temperature for 1 hour until the reaction was complete. The mixture was then allowed to stand for a period of time to allow the precipitate to settle naturally. The precipitate was washed using vacuum filtration. After washing, the precipitate was transferred to an oven and dried at 120℃ for 5 hours to obtain a light yellow Bi-Zn-V precursor powder. The precursor powder was transferred to a muffle furnace and calcined in air at 700℃ for 1 hour. After cooling to room temperature, BiZn2VO6 material was obtained.

[0025] Example 3

[0026] The difference between this embodiment and Embodiments 1 and 2 is that the calcination time is 4 hours. The specific preparation method is as follows:

[0027] Bi(NO3)3·5H2O, Zn(NO3)2·6H2O, and NH4VO3 were weighed out according to a stoichiometric ratio of 1:2:1. NH4VO3 was dissolved in deionized water at 80℃ to obtain a pale yellow solution A with a concentration of 0.07 mol / L. Bi(NO3)3·5H2O and Zn(NO3)2·6H2O were added to deionized water, and nitric acid was added dropwise until completely dissolved to obtain a colorless solution B. Bi... 3+ The concentration of Zn is 0.11 mol / L.2+ The concentration was 0.22 mol / L. Solution A was mixed with solution B, and the pH was adjusted to 8.0 using ammonia. The mixture was stirred continuously at room temperature for 1 hour until the reaction was complete, and then allowed to stand for a period of time to allow the precipitate to settle naturally. The precipitate was washed by vacuum filtration, and then transferred to an oven and dried at 120℃ for 5 hours to obtain a light yellow Bi-Zn-V precursor powder. The precursor powder was transferred to a muffle furnace and calcined in air at 700℃ for 4 hours. After cooling to room temperature, BiZn2VO6 material was obtained.

[0028] Example 4

[0029] The difference between this embodiment and embodiments 1-3 is that the calcination temperature is 800℃. The specific preparation method is as follows:

[0030] Bi(NO3)3·5H2O, Zn(NO3)2·6H2O, and NH4VO3 were weighed out according to a stoichiometric ratio of 1:2:1. NH4VO3 was dissolved in deionized water at 80℃ to obtain a pale yellow solution A with a concentration of 0.07 mol / L. Bi(NO3)3·5H2O and Zn(NO3)2·6H2O were added to deionized water, and nitric acid was added dropwise until completely dissolved to obtain a colorless solution B. Bi... 3+ The concentration of Zn is 0.11 mol / L. 2+ The concentration was 0.22 mol / L. Solution A was mixed with solution B, and the pH was adjusted to 8.0 using ammonia. The mixture was stirred continuously at room temperature for 1 hour until the reaction was complete, and then allowed to stand for a period of time to allow the precipitate to settle naturally. The precipitate was washed by vacuum filtration, and then transferred to an oven and dried at 120℃ for 5 hours to obtain a light yellow Bi-Zn-V precursor powder. The precursor powder was transferred to a muffle furnace and calcined in air at 800℃ for 2 hours. After cooling to room temperature, BiZn2VO6 material was obtained.

[0031] Example 5

[0032] The difference between this embodiment and Examples 1-4 is that the pH of the solution is adjusted to 7.0. The specific preparation method is as follows:

[0033] Bi(NO3)3·5H2O, Zn(NO3)2·6H2O, and NH4VO3 were weighed out according to a stoichiometric ratio of 1:2:1. NH4VO3 was dissolved in deionized water at 80℃ to obtain a pale yellow solution A with a concentration of 0.07 mol / L. Bi(NO3)3·5H2O and Zn(NO3)2·6H2O were added to deionized water, and nitric acid was added dropwise until completely dissolved to obtain a colorless solution B. Bi...3+ The concentration of Zn is 0.11 mol / L. 2+ The concentration was 0.22 mol / L. Solution A was mixed with solution B, and the pH was adjusted to 7.0 using ammonia. The mixture was stirred continuously at room temperature for 1 hour until the reaction was complete, and then allowed to stand for a period of time to allow the precipitate to settle naturally. The precipitate was washed by vacuum filtration, and then transferred to an oven and dried at 120℃ for 5 hours to obtain a light yellow Bi-Zn-V precursor powder. The precursor powder was transferred to a muffle furnace and calcined in air at 700℃ for 2 hours. After cooling to room temperature, BiZn2VO6 material was obtained.

[0034] Example 6

[0035] The difference between this embodiment and embodiments 1-5 is that, after adjusting the pH of the solution with ammonia, the mixture was stirred continuously at room temperature for 2 hours until the reaction was complete. The specific preparation method is as follows:

[0036] Bi(NO3)3·5H2O, Zn(NO3)2·6H2O, and NH4VO3 were weighed out according to a stoichiometric ratio of 1:2:1. NH4VO3 was dissolved in deionized water at 80℃ to obtain a pale yellow solution A with a concentration of 0.07 mol / L. Bi(NO3)3·5H2O and Zn(NO3)2·6H2O were added to deionized water, and nitric acid was added dropwise until completely dissolved to obtain a colorless solution B. Bi... 3+ The concentration of Zn is 0.11 mol / L. 2+ The concentration was 0.22 mol / L. Solution A was mixed with solution B, and the pH was adjusted to 8.0 using ammonia. The mixture was stirred continuously at room temperature for 2 hours until the reaction was complete. The mixture was then allowed to stand for a period of time to allow the precipitate to settle naturally. The precipitate was washed using vacuum filtration. After washing, the precipitate was transferred to an oven and dried at 120℃ for 5 hours to obtain a light yellow Bi-Zn-V precursor powder. The precursor powder was transferred to a muffle furnace and calcined in air at 800℃ for 2 hours. After cooling to room temperature, BiZn2VO6 material was obtained.

[0037] Example 7

[0038] The difference between this embodiment and Examples 1-6 is that the concentrations of the metal cations are different. The specific preparation method is as follows:

[0039] Bi(NO3)3·5H2O, Zn(NO3)2·6H2O, and NH4VO3 were weighed out according to a stoichiometric ratio of 1:2:1. NH4VO3 was dissolved in deionized water at 80℃ to obtain a pale yellow solution A with a concentration of 0.05 mol / L. Bi(NO3)3·5H2O and Zn(NO3)2·6H2O were added to deionized water, and nitric acid was added dropwise until completely dissolved to obtain a colorless solution B. Bi... 3+ The concentration of Zn is 0.08 mol / L. 2+ The concentration was 0.16 mol / L. Solution A was mixed with solution B, and the pH was adjusted to 8.0 using ammonia. The mixture was stirred continuously at room temperature for 2 hours until the reaction was complete. The mixture was then allowed to stand for a period of time to allow the precipitate to settle naturally. The precipitate was washed using vacuum filtration. After washing, the precipitate was transferred to an oven and dried at 120℃ for 3 hours to obtain a light yellow Bi-Zn-V precursor powder. The precursor powder was transferred to a muffle furnace and calcined in air at 700℃ for 2 hours. After cooling to room temperature, BiZn2VO6 material was obtained.

[0040] Figure 1 and Figure 2 The XRD patterns of the BiZn2VO6 microwave dielectric ceramic powders prepared in Examples 1-5 show that the diffraction peaks are high and no impurity peaks are present, indicating that highly crystalline BiZn2VO6 material has been generated.

[0041] The basic principles and main features of the present invention have been described above. However, the above description is only a specific embodiment of the present invention. The technical features of the present invention are not limited thereto. All implementation schemes that meet the requirements of the present invention are within the scope of the present invention.

Claims

1. A method for preparing BiZn2VO6 microwave dielectric ceramic powder at low temperature, characterized in that, The steps are as follows: (1) Bi(NO3)3·5H2O, Zn(NO3)2·6H2O and NH4VO3 are weighed according to the mass ratio of 1:2:1 as raw materials; (2) NH4VO3 weighed in step (1) is added to water, and continuously stirred under water bath heating at 80℃ until completely dissolved, with a concentration of 0.05-0.07 mol / L; (3) adding Bi(NO3)3.5H2O and Zn(NO3)2.6H2O weighed in step (1) into water, adding nitric acid dropwise and continuously stirring until completely dissolved; wherein the concentration of Bi 3+ is 0.08-0.11 mol / L, and the concentration of Zn 2+ is 0.16-0.22 mol / L; (4) After mixing the solutions obtained in steps (2) and (3), the pH value of the solution is adjusted to 7.0-8.0 with ammonia water, and continuously stirred at room temperature for 1-2 h until complete reaction, and then left for a period of time to wait for the precipitate to naturally sink; (5) The precipitate obtained in step (4) is washed by reduced pressure suction filtration, and after washing, the precipitate is transferred to an oven, dried at 120℃ for 3-5 h to obtain a precursor powder; (6) The precursor powder obtained in step (5) is transferred to a muffle furnace and calcined at 700-800℃ for 1-4 h to obtain a BiZn2VO6 material.

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