Nano ceramic powder as well as preparation method and application thereof
By using ammonia water or ammonia precipitation method in the preparation of ceramic powder, high-temperature calcination is avoided, and small-grain nanoceramic powder with high sintering activity is successfully prepared, solving the problems of complex preparation and low sintering activity in the prior art. Improved performance of solid oxide fuel cells.
Patent Information
- Application Number
- CN202411605079.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-12
- Publication Date
- 2025-02-21
AI Technical Summary
The existing ceramic powder preparation methods are complex and require high temperature calcination, which leads to high preparation cost and low sintering activity. Especially in solid oxide fuel cells, high sintering active materials are difficult to achieve.
By mixing the raw material of the target product with solvent and acid, precipitation with ammonia water or ammonia gas, stirring and ultrasonic dispersion, a nanoceramic powder is obtained, avoiding high-temperature calcination.
The preparation of ceramic powder is achieved at room temperature, the process is simple, the generated nanoceramic powder particles are small, and the sintering activity is high. It is suitable for the anode, cathode and electrolyte materials of solid oxide fuel cells, improving the battery performance.
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Figure CN119490351A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of ceramic powder preparation, and in particular to a nano ceramic powder and a preparation method and application thereof. Background Art
[0002] Solid oxide fuel cell (SOFC) is a highly efficient energy conversion device that can directly convert chemical energy into electrical energy. The core components of SOFC include electrolyte, cathode (positive electrode) and anode (negative electrode), all of which are ceramic materials. There are many methods for preparing ceramic powders, such as sol-gel method, hydrothermal method, co-precipitation method, etc., but these methods are relatively complicated, require multiple steps, and need to be calcined to generate pure phase, which greatly increases the preparation cost; furthermore, the ceramic powder prepared according to the above method is large in size and has low sintering activity. If high sintering activity is required, secondary granulation is required. In addition, the densification temperature of the electrolyte is usually high (≥1400℃), and too high calcination temperature will reduce the electrode activity, which is not conducive to the electrochemical reaction.
[0003] Therefore, it is necessary to provide a method for preparing ceramic powder, which has a simple preparation process and can be formed into a phase without high-temperature calcination, and the size of the prepared ceramic powder can improve its sintering activity. Summary of the invention
[0004] The present disclosure provides a nano-ceramic powder and a preparation method and application thereof, so as to at least solve the above technical problems existing in the prior art.
[0005] According to a first aspect of the present disclosure, a method for preparing nano-ceramic powder is provided, comprising the following steps:
[0006] S1: mixing the raw material of the target product with a solvent in a stoichiometric ratio; or mixing the raw material of the target product with a solvent and an acid in a stoichiometric ratio to obtain a mixed solution;
[0007] S2: placing ammonia water and the mixed solution in step S1 in the same space; or introducing ammonia gas into the mixed solution in step S1, and obtaining a precipitate after stirring and ultrasonic dispersion; and obtaining the nano-ceramic powder after drying the precipitate.
[0008] Specifically, the above-mentioned target product refers to the nano-ceramic powder to be prepared in the end, which can be used as any one of the anode material, cathode material, and electrolyte material of the solid oxide fuel cell.
[0009] In one embodiment, in step S1, if the raw material of the target product is mixed with the solvent in a stoichiometric ratio, the raw material of the target product is selected from the salt of the target product; if the raw material of the target product is mixed with the solvent and the acid in a stoichiometric ratio, the raw material of the target product is selected from at least one of the salt of the target product and the oxide of the target product.
[0010] In one embodiment, the salt of the target product is selected from at least one of the nitrate, carbonate, chloride and acetate of the target product.
[0011] Specifically, the salt of the target product is not limited to the above-mentioned salts.
[0012] Specifically, the salt of the target product or the oxide of the target product is a salt or oxide corresponding to each element in the target product.
[0013] In one embodiment, the solvent is selected from at least one of water, methanol, ethanol, acetone, isopropanol, and xylene.
[0014] Specifically, the solvent is not limited to the above-mentioned options, as long as it can dissolve the raw materials of the target product and does not react with the raw materials of the target product.
[0015] In one embodiment, the acid is selected from at least one of hydrochloric acid, sulfuric acid, nitric acid, nitrous acid, and formic acid.
[0016] In one embodiment, the stirring speed in step S2 is 0 to 3000 r / min.
[0017] In one embodiment, the frequency of the ultrasonic wave in step S2 is 20-40 kHz.
[0018] In one embodiment, in step S2, the precipitate is filtered, washed or centrifuged before being dried.
[0019] According to a second aspect of the present disclosure, a nano-ceramic powder prepared according to the above preparation method is provided.
[0020] According to a third aspect of the present disclosure, a solid oxide fuel cell is provided, which includes an anode, a cathode and an electrolyte; the material of the anode, the cathode or the electrolyte includes a nano-ceramic powder prepared according to the above preparation method.
[0021] According to an implementable embodiment of the present disclosure, at least the following beneficial effects are achieved:
[0022] The present disclosure proposes a method for preparing nano ceramic powder at room temperature, which has a simple process, uses gaseous ammonia as a precipitant to nano-size the powder, and can form a phase without high-temperature calcination; and the particles of the prepared nano ceramic powder are small, which can greatly improve its sintering activity. The nano ceramic powder prepared according to the method of the present disclosure is used to prepare the anode, cathode and electrolyte of a solid oxide fuel cell, which can improve the performance of the battery.
[0023] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present disclosure are shown in an exemplary and non-limiting manner, in which:
[0025] In the drawings, the same or corresponding reference numerals represent the same or corresponding parts.
[0026] Figure 1 The nano ceramic powder Gd in Example 1 of the present disclosure is shown. 0.1 Ce 0.9 XRD scan of O2;
[0027] Figure 2 The nano ceramic powder Sm in Example 2 of the present disclosure is shown. 0.2 Ce 0.8 TG curve of O2;
[0028] Figure 3 The nano ceramic powder Y in Example 4 of the present disclosure is shown 0.16 Zr 0.84 SEM image of O2;
[0029] Figure 4 The nano ceramic powder BaZr is used in Example 5 of the present disclosure. 0.3 Ce 0.5 Y 0.2 Surface SEM image of the test sample prepared by O3. DETAILED DESCRIPTION
[0030] In order to make the purpose, features, and advantages of the present disclosure more obvious and easy to understand, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present disclosure.
[0031] Example 1
[0032] This example prepares nano ceramic powder Gd 0.1 Ce 0.9 O2, the specific process is as follows:
[0033] (1) Dissolve gadolinium nitrate and cerium nitrate in water at a stoichiometric ratio of 0.1:0.9 to obtain a mixed solution.
[0034] (2) placing ammonia water and the mixed solution of step (1) in the same space, stirring the mixed solution and performing ultrasonic dispersion, wherein the stirring speed is 0 r / min and the ultrasonic frequency is 20 kHz, to obtain a precipitate; filtering and washing the precipitate, and then drying it at -120°C to obtain a nano-ceramic powder Gd 0.1 Ce 0.9 O2.
[0035] The nano ceramic powder Gd 0.1 Ce 0.9 O2 was subjected to X-ray diffraction analysis, and the results were as follows Figure 1 shown. Figure 1 The results show that the diffraction peaks of Gd, Ce and O were detected, indicating that the nano-ceramic powder is composed of Gd, Ce and O, and the target product was successfully prepared by the above method.
[0036] Example 2
[0037] This example prepares nano ceramic powder Sm 0.2 Ce 0.8 O2, the specific process is as follows:
[0038] (1) Samarium oxide and cerium oxide are dissolved in methanol at a stoichiometric ratio of 0.2:0.8, and an equal amount of hydrochloric acid is added to dissolve to obtain a mixed solution.
[0039] (2) introducing ammonia gas into the mixed solution of step (1), and stirring and ultrasonically dispersing the mixed solution, wherein the stirring speed is 500 r / min and the frequency of the ultrasonic wave is 30 kHz, to obtain a precipitate; high-speed centrifuging the precipitate, and then freeze-drying it at -20°C to obtain a nano-ceramic powder Sm 0.2 Ce 0.8 O2.
[0040] The above-mentioned nano-ceramic powder Sm 0.2 Ce 0.8 The weight of O2 changes with temperature. Figure 2 shown. Figure 2 It shows that when the temperature rises from room temperature to 1000°C, the weight reduction of the nano-ceramic powder is within 5%, indicating that the structure of the nano-ceramic powder is relatively stable, can withstand a certain temperature, and is suitable as a material for solid oxide fuel cells.
[0041] Example 3
[0042] In this example, nano ceramic powder La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O3, the specific process is as follows:
[0043] (1) Lanthanum oxide, strontium acetate, cobalt carbonate, and ferric nitrate are dissolved in isopropanol in a stoichiometric ratio of 0.6:0.4:0.2:0.8, and an equal amount of nitric acid is added to dissolve the mixture to obtain a mixed solution.
[0044] (2) introducing ammonia into the mixed solution of step (1), and stirring and ultrasonically dispersing the mixed solution, wherein the stirring speed is 1000 r / min and the frequency of the ultrasonic wave is 40 kHz, to obtain a precipitate; high-speed centrifuging the precipitate, and then drying it at 200° C. to obtain a nano-ceramic powder La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O3.
[0045] Example 4
[0046] This example prepares nano ceramic powder Y 0.16 Zr 0.84 O2, the specific process is as follows:
[0047] (1) Dissolve yttrium oxide and zirconium nitrate in water at a stoichiometric ratio of 0.16:0.84, and add an equal amount of nitric acid to dissolve to obtain a mixed solution.
[0048] (2) placing ammonia water and the mixed solution of step (1) in the same space, and stirring and ultrasonically dispersing the mixed solution, wherein the stirring speed is 2000r / min and the frequency of the ultrasonic wave is 25kHz, to obtain a precipitate; filtering and washing the precipitate, and then drying it at 50°C to obtain a nano-ceramic powder Y 0.16 Zr 0.84 O2.
[0049] The nano ceramic powder Y 0.16 Zr 0.84O2 was observed under a scanning electron microscope. Figure 3 shown. Figure 3 It shows that the particle size of the nano-ceramic powder is small, about 20nm, which shows that the nano-ceramic powder has a high sintering activity.
[0050] Example 5
[0051] In this example, nano ceramic powder BaZr was prepared. 0.3 Ce 0.5 Y 0.2 O3, the specific process is as follows:
[0052] (1) Barium chloride, zirconium acetate, cerium oxide, and yttrium nitrate are dissolved in acetone in a stoichiometric ratio of 1:0.3:0.5:0.2, and an equal amount of hydrochloric acid is added to dissolve the mixture to obtain a mixed solution.
[0053] (2) introducing ammonia into the mixed solution of step (1), stirring the mixed solution and performing ultrasonic dispersion, wherein the stirring speed is 3000 r / min and the ultrasonic frequency is 20 kHz, to obtain a precipitate; centrifuging the precipitate at high speed, and then drying at 250° C. to obtain nano-ceramic powder BaZr 0.3 Ce 0.5 Y 0.2 O3.
[0054] The nano ceramic powder BaZr 0.3 Ce 0.5 Y 0.2 O3 was pressed into a sheet-like body, and then calcined at 1300°C to obtain a test sample. The test sample was placed under a scanning electron microscope to observe its microscopic morphology. The results are as follows Figure 4 shown. Figure 4 The results show that the densification degree of the test sample is relatively high. The nano ceramic powder in this embodiment is used to prepare a solid oxide fuel cell, which can improve the electrode activity and thus facilitate the electrochemical reaction.
[0055] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of this disclosure can be achieved, and this document is not limited here.
[0056] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0057] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.
Claims
1. A method for preparing nano ceramic powder, characterized in that: The following steps are involved: S1: mixing the raw material of the target product with a solvent in a stoichiometric ratio; or mixing the raw material of the target product with a solvent and an acid in a stoichiometric ratio to obtain a mixed solution; S2: placing ammonia water and the mixed solution in step S1 in the same space; or introducing ammonia gas into the mixed solution in step S1, and obtaining a precipitate after stirring and ultrasonic dispersion; and obtaining the nano-ceramic powder after drying the precipitate.
2. The preparation method according to claim 1, characterized in that: In step S1, if the raw material of the target product is mixed with the solvent in a stoichiometric ratio, the raw material of the target product is selected from the salt of the target product; if the raw material of the target product is mixed with the solvent and the acid in a stoichiometric ratio, the raw material of the target product is selected from at least one of the salt of the target product and the oxide of the target product.
3. The preparation method according to claim 2, characterized in that: The salt of the target product or the oxide of the target product is the salt or oxide corresponding to each element in the target product.
4. The preparation method according to claim 2, characterized in that: The salt of the target product is selected from at least one of the nitrate, carbonate, chloride and acetate of the target product.
5. The preparation method according to claim 1, characterized in that: The solvent is selected from at least one of water, methanol, ethanol, acetone, isopropanol and xylene.
6. The preparation method according to claim 1, characterized in that: The acid is selected from at least one of hydrochloric acid, sulfuric acid, nitric acid, nitrous acid and formic acid.
7. The preparation method according to claim 1, characterized in that: The stirring speed in step S2 is 0 to 3000 r / min; Preferably, the frequency of the ultrasonic wave in step S2 is 20-40 kHz.
8. The preparation method according to claim 1, characterized in that: Step S2: filtering, washing or centrifuging the precipitate and then drying it.
9. Nano-ceramic powder obtained according to the preparation method according to any one of claims 1 to 8.
10. A solid oxide fuel cell, characterized in that: The solid oxide fuel cell comprises an anode, a cathode and an electrolyte; the material of the anode, the cathode or the electrolyte comprises nano-ceramic powder obtained according to the preparation method according to any one of claims 1 to 8.