A B-site doped high-entropy lead stannate ceramic powder and its preparation method

Abstract

This invention discloses a B-site-doped high-entropy lead stannate ceramic powder and its preparation method, belonging to the field of high-entropy ceramic materials technology. The chemical formula of the B-site-doped high-entropy lead stannate ceramic powder provided by this invention is: Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 The preparation method of this ceramic powder is as follows: PbO, SnO2, Nb2O5, Sc2O3, CeO2, and ZrO2 powders are weighed according to the stoichiometric ratio of the chemical formula. To compensate for the volatilization of Pb, an additional 10% of the mass of PbO powder is weighed. The raw materials are mixed, ball-milled, dried, and then ground. After sintering and sieving, B-site doped high-entropy lead stannate ceramic powder is obtained. This invention dops Ce into the B-site of PbSnO3, and selects Zr, Sc, Nb, and Sn as the other four elements for the B-site. The five chemical elements have similar chemical properties and small differences in ionic radius, making it easy to form a solid solution. The resulting B-site doped high-entropy lead stannate ceramic powder achieves a high entropy at 10⁻⁶ ppm. 3 -10 7 At a test frequency of Hz, the dielectric constant of the material remains stable at room temperature, and the dielectric loss is reduced.

Description

Technical Field

[0001] This invention belongs to the field of high-entropy ceramic materials technology, and particularly relates to a B-site doped high-entropy lead stannate ceramic powder and its preparation method. Background Technology

[0002] With the rapid development of electronic technology, the demand for high-performance dielectric ceramic materials is increasing. Lead stannate (PbSnO3), as a common dielectric ceramic material, has been widely studied and applied due to its excellent dielectric properties. However, traditional lead stannate ceramics still have some limitations in practical applications, such as low dielectric constant, high dielectric loss, and insufficient high-temperature stability. To overcome these shortcomings, researchers have modified lead stannate ceramics through doping techniques to improve their performance.

[0003] High-entropy ceramics are a novel type of multi-principal-element solid solution ceramic, formed by doping five or more elements in equal proportions. These materials possess excellent physical and chemical properties, such as high-entropy effects, lattice distortion effects, and multiple phase transition effects. In the research of high-entropy ceramics, Ce doping is widely used, especially in A-site doping. However, research on doping Ce into the B-site of lead stannate is relatively limited.

[0004] CeO2, as a dopant, possesses unique physical and chemical properties. During high-temperature sintering, CeO2 readily generates oxygen vacancies, leading to Ce... 4+ The oxidation state of Ce is reduced to Ce 3+ Ce 3+ Ce has a relatively large ionic radius and typically tends to enter the A-site. This invention controls the sintering temperature to allow Ce to... 4+ Maintaining the +4 valence state makes it easier to enter the B site and form a solid solution. This unique doping method is expected to significantly improve the dielectric properties of lead stannate ceramics while reducing dielectric loss.

[0005] Furthermore, traditional methods for preparing lead stannate ceramics typically require specific atmosphere control or the addition of sintering aids, resulting in complex processes and high costs. Therefore, developing a simple, efficient, and low-cost preparation method is of great significance for promoting the practical application of high-entropy lead stannate ceramics. Summary of the Invention

[0006] The purpose of this invention is to provide a B-site doped high-entropy lead stannate ceramic powder and its preparation method. This invention provides a simple, efficient, and low-cost method for preparing B-site doped high-entropy lead stannate ceramic powder, thereby solving the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] This invention provides a B-site doped high-entropy lead stannate ceramic powder, the chemical formula of which is: Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 )O3.

[0009] This invention also provides a method for preparing B-site doped high-entropy lead stannate ceramic powder, comprising the following steps: weighing PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of the chemical formula, and additionally weighing 10% of the mass of PbO powder, mixing the raw materials, ball milling, drying and grinding, sintering and sieving to obtain B-site doped high-entropy lead stannate ceramic powder.

[0010] Preferably, the ball milling process conditions are as follows: ball milling speed is 300 rpm, ball milling time is 12 to 24 hours, the ball milling media are anhydrous ethanol and zirconium oxide balls, and the mass ratio of zirconium oxide balls, mixed raw materials and anhydrous ethanol is 5:1:5.

[0011] Preferably, the drying time is 12-24 hours and the drying temperature is 80-100℃.

[0012] Preferably, the grinding time is 30-60 minutes.

[0013] Preferably, the sintering conditions are as follows: heating from room temperature to 730-750°C at a heating rate of 3°C / min, holding at that temperature for 1.9-2.1 hours, and then cooling to room temperature with the furnace.

[0014] Preferably, the mesh size of the sieve used for sieving is 80 to 100 mesh.

[0015] Preferably, the preparation method of the B-site doped high-entropy lead stannate ceramic powder specifically includes the following steps:

[0016] (1) According to Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 Weigh PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of O3. Weigh an additional 10% of the mass of PbO. Put the above powders into a ball mill and ball mill them for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and mixed raw materials of 5:5:1. The ball mill speed is 300 rpm to obtain ceramic slurry.

[0017] (2) The ceramic slurry obtained in step (1) is placed in an oven for drying. The drying temperature of the oven is 80℃ and the drying time is 15h.

[0018] (3) Place the dried ceramic powder from step (2) into a grinding jar and grind for 30 minutes. Place the ground ceramic powder into a crucible and put the crucible into a muffle furnace. Heat the crucible to 750°C at a heating rate of 3°C / min and keep it in the muffle furnace for 2 hours. Then cool it to room temperature with the furnace. Then pass the sintered powder through an 80-mesh sieve to obtain B-site doped high-entropy lead stannate ceramic powder.

[0019] The present invention discloses the following technical effects:

[0020] 1. This invention employs a ball milling and high-temperature sintering process, which eliminates the need for specific atmosphere control and sintering aids, simplifying the preparation process, reducing production costs, and improving preparation efficiency.

[0021] 2. The B-site-doped high-entropy lead stannate ceramic powder prepared by this invention exhibits excellent dielectric properties, with a dielectric strength of 10 at room temperature. 3 Hz-10 7 The dielectric constant remains stable (48-62) within the Hz frequency range, and the dielectric loss is low (below 0.06), which can meet the requirements of high-performance dielectric ceramic materials. The ceramic powder material of this invention has a single-phase perovskite structure, uniform element distribution, and no element segregation, which ensures the stability and consistency of material performance.

[0022] 3. This invention is the first to dope Ce at the B-site of lead stannate, forming a single-phase solid solution, overcoming the problem of Ce entering the A-site due to valence state change when doped at the B-site. During sintering, by controlling the sintering temperature, Ce is kept in the +4 valence state, making it easier to enter the B-site and form a solid solution, thus fully utilizing the advantages of Ce doping. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 The XRD patterns are of the high-entropy ceramic powders prepared in Example 1 and Comparative Example 1.

[0025] Figure 2 The image shows the SEM image (top left) and EDS image of the high-entropy ceramic powder prepared in Example 1.

[0026] Figure 3 The dielectric constant diagram of the high-entropy ceramic powder prepared in Example 1 is shown.

[0027] Figure 4 The dielectric loss diagram is for the high-entropy ceramic powder prepared in Example 1. Detailed Implementation

[0028] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0029] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0030] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0031] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0032] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0033] This invention provides a method for preparing B-site doped high-entropy lead stannate ceramic powder, comprising the following steps: weighing PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of the chemical formula, and additionally weighing 10% of the mass of PbO powder, mixing the raw materials, ball milling, drying and grinding, sintering and sieving to obtain B-site doped high-entropy lead stannate ceramic powder.

[0034] In some embodiments of the present invention, the ball milling process conditions are as follows: the ball milling speed is 300 rpm, the ball milling time is 12 to 24 hours, the ball milling media are anhydrous ethanol and zirconia balls, and the mass ratio of zirconia balls, mixed raw materials and anhydrous ethanol is 5:1:5.

[0035] The purpose of drying is to remove anhydrous ethanol from the ball milling media during the ball milling process, preventing residual ethanol from damaging the internal structure of the ceramic powder during sintering. In some embodiments of the present invention, the drying time is 12-24 hours, and the drying temperature is 80-100°C. Optionally, when the drying temperature is 80°C, the drying time can be 15 hours. When the drying temperature is 90°C, the drying time can be 12 hours; when the drying temperature is 100°C, the drying time can be 13 hours.

[0036] In some embodiments of the present invention, the grinding time is 30-60 minutes.

[0037] In some embodiments of the present invention, the sintering conditions are as follows: heating from room temperature to 730-750°C at a heating rate of 3°C / min, holding at that temperature for 1.9-2.1 hours, and then cooling to room temperature in the furnace. In some embodiments, the sintering temperature may be selected as 740°C, 750°C, or 730°C, and the sintering time may be selected as 1.9 hours, 2.0 hours, or 2.1 hours.

[0038] In some embodiments of the present invention, the mesh size of the sieve used for sieving is 80 to 100 mesh.

[0039] Example 1

[0040] A method for preparing B-site doped high-entropy lead stannate ceramic powder includes the following steps:

[0041] (1) According to Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 Weigh PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of O3. To compensate for the volatilization of Pb, weigh an additional 10% of the mass of PbO. Put the above powders into a ball mill and ball mill them for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and mixed raw materials of 5:5:1. The ball mill speed is 300 rpm to obtain ceramic slurry.

[0042] (2) The ceramic slurry obtained in step (1) is placed in an oven for drying at a temperature of 80°C for 15 hours.

[0043] (3) Place the dried ceramic powder from step (2) into a grinding jar and grind for 30 minutes. Place the ground ceramic powder into a crucible and put the crucible into a muffle furnace. Heat the crucible to 750°C at a heating rate of 3°C / min and keep it in the muffle furnace for 2 hours. Then cool it to room temperature with the furnace. Then pass the sintered powder through an 80-mesh sieve to obtain B-site doped high-entropy lead stannate ceramic powder.

[0044] Figure 2 The SEM and EDS images of the high-entropy ceramic powder prepared in Example 1 are shown below. Figure 2 As can be seen, the prepared high-entropy ceramic powder has a uniform elemental distribution and no elemental segregation.

[0045] Figure 3 The dielectric constant diagram of the high-entropy ceramic prepared in Example 1 is shown in 10. 3 Hz-10 7 Under Hz testing at room temperature, the dielectric constant of the ceramic powder is 53-60. The dielectric constant is stable.

[0046] Figure 4 The dielectric loss diagram of the high-entropy ceramic prepared in Example 1 is shown in 10. 3 Hz-10 7 Under Hz testing at room temperature, the dielectric loss of the ceramic powder is below 0.05. The dielectric loss is relatively low.

[0047] Example 2

[0048] A method for preparing B-site doped high-entropy lead stannate ceramic powder includes the following steps:

[0049] (1) According to Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 Weigh PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of O3. To compensate for the volatilization of Pb, weigh an additional 10% of the mass of PbO. Put the above powders into a ball mill and ball mill them for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and mixed raw materials of 5:5:1. The ball mill speed is 300 rpm to obtain ceramic slurry.

[0050] (2) The ceramic slurry obtained in step (1) is placed in an oven for drying at a temperature of 90°C for 12 hours.

[0051] (3) Place the dried ceramic powder from step (2) into a grinding jar and grind for 30 minutes. Place the ground ceramic powder into a crucible and put the crucible into a muffle furnace. Heat the crucible to 730°C at a heating rate of 3°C / min and keep it in the muffle furnace for 2 hours. Then cool it to room temperature with the furnace. Then pass the sintered powder through an 80-mesh sieve to obtain B-site doped high-entropy lead stannate ceramic powder.

[0052] In 10 3 Hz-10 7 Under Hz testing at room temperature, the dielectric constant of the B-site-doped high-entropy lead stannate ceramic powder of Example 2 is 51-62. The dielectric constant is stable. 3 Hz-10 7 Under Hz testing at room temperature, the dielectric loss of the B-site doped high-entropy lead stannate ceramic powder in Example 2 is below 0.06. The dielectric loss is relatively low.

[0053] Example 3

[0054] A method for preparing B-site doped high-entropy lead stannate ceramic powder includes the following steps:

[0055] (1) According to Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 Weigh PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of O3. To compensate for the volatilization of Pb, weigh an additional 10% of the mass of PbO. Put the above powders into a ball mill and ball mill them for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and mixed raw materials of 5:5:1. The ball mill speed is 300 rpm to obtain ceramic slurry.

[0056] (2) The ceramic slurry obtained in step (1) is placed in an oven for drying at a temperature of 100°C for 13 hours.

[0057] (3) Place the dried ceramic powder from step (2) into a grinding jar and grind for 30 min. Place the ground ceramic powder into a crucible and put the crucible into a muffle furnace. Heat the crucible to 740°C at a heating rate of 3°C / min and keep it in the muffle furnace for 2 h. Then cool it to room temperature with the furnace. Then pass the sintered powder through an 80-mesh sieve to obtain B-site doped high-entropy lead stannate ceramic powder.

[0058] In 10 3 Hz-10 7Under Hz testing at room temperature, the dielectric constant of the B-site doped high-entropy lead stannate ceramic powder in Example 3 is 48-56. The dielectric constant is stable. 3 Hz-10 7 Under Hz testing at room temperature, the dielectric loss of the B-site doped high-entropy lead stannate ceramic powder in Example 3 is below 0.06. The dielectric loss is relatively low.

[0059] Comparative Example 1

[0060] A method for preparing B-site doped high-entropy lead stannate ceramic powder includes the following steps:

[0061] (1) According to Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 Weigh PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of O3. To compensate for the volatilization of Pb, weigh an additional 10% of the mass of PbO. Put the above powders into a ball mill and ball mill them for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and mixed raw materials of 5:5:1. The ball mill speed is 300 rpm to obtain ceramic slurry.

[0062] (2) The ceramic slurry obtained in step (1) is placed in an oven for drying at a temperature of 80°C for 15 hours.

[0063] (3) Place the dried ceramic powder from step (2) into a grinding jar and grind it for 30 minutes. Then place the ground ceramic powder into a crucible and put the crucible into a muffle furnace. Heat the crucible to 800°C at a heating rate of 3°C / min and keep it in the muffle furnace for 2 hours. Then cool it to room temperature with the furnace. Finally, pass the sintered powder through an 80-mesh sieve to obtain B-site doped high-entropy lead stannate ceramic powder.

[0064] Figure 1 XRD patterns of the high-entropy ceramic powders prepared in Example 1 and Comparative Example 1. Figure 1 As can be seen from the data, the high-entropy ceramic powder prepared in Example 1 has a single-phase perovskite structure. The presence of impurity peaks in Comparative Example 1 indicates that excessively high sintering temperatures can affect the structure and stability of B-site doped high-entropy lead stannate ceramic powder.

[0065] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A B-site-doped high-entropy lead stannate ceramic powder, characterized in that, The chemical formula of the ceramic powder is: Pb(Zr) 0.2 Sn 0.2 Sc 0.2 Nb 0.2 Ce 0.2 O3; A method for preparing B-site doped high-entropy lead stannate ceramic powder, characterized by the following steps: weighing PbO, SnO2, Nb2O5, Sc2O3, CeO2 and ZrO2 powders according to the stoichiometric ratio of the chemical formula; in order to compensate for the volatilization of Pb element, additionally weighing 10% of the mass of PbO powder; mixing the raw materials, ball milling, drying and grinding; sintering and sieving to obtain B-site doped high-entropy lead stannate ceramic powder; The sintering conditions are as follows: heating from room temperature to 730-750℃ at a heating rate of 3℃ / min, holding at that temperature for 1.9-2.1h, and then cooling to room temperature with the furnace.

2. The B-site doped high-entropy lead stannate ceramic powder according to claim 1, characterized in that, The ball milling process conditions are as follows: the ball milling speed is 300 rpm, the ball milling time is 12-24 hours, the ball milling media are anhydrous ethanol and zirconia balls, and the mass ratio of zirconia balls, mixed raw materials and anhydrous ethanol is 5:1:

5.

3. The B-site-doped high-entropy lead stannate ceramic powder according to claim 1, characterized in that, The drying time is 12-24 hours, and the drying temperature is 80-100℃.

4. The B-site-doped high-entropy lead stannate ceramic powder according to claim 1, characterized in that, The grinding time is 30-60 minutes.

5. The B-site doped high-entropy lead stannate ceramic powder according to claim 1, characterized in that, The sieve mesh size is 80-100 mesh.

6. The use of the B-site doped high-entropy lead stannate ceramic powder as described in claim 1 as a high-performance dielectric ceramic material.

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