A B-site doped medium-entropy lanthanum nickelate ceramic spray powder and preparation method thereof

Abstract

The present invention discloses a B-doped medium entropy lanthanum nickelate ceramic spray powder and a preparation method thereof, belonging to the technical field of spraying materials. The chemical formula of the B-doped medium entropy lanthanum nickelate ceramic spray powder provided by the present invention is: La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3. The present invention performs entropy design on the B site of lanthanum nickelate ceramics and dopes three suitable elements in equal molar ratio into the B site lattice of lanthanum nickelate ceramics, thereby causing a lattice distortion effect of lanthanum nickelate, increasing its disorder, improving the spraying performance of lanthanum nickelate ceramics, and thus reducing the cell voltage of hydrogen production by electrolysis of water. 1 / 3 Co 1 / 3 Mn 1 / 3 )After the O3 medium-entropy ceramic powder is sprayed onto the nickel mesh, the voltage of the small chamber for electrolyzing water to produce hydrogen on the nickel mesh is reduced by an average of 0.03V compared with the light mesh, which has the advantages of energy saving and environmental protection.

Description

Technical Field

[0001] The present invention belongs to the technical field of spraying materials, and in particular relates to a B-site doped medium-entropy lanthanum nickelate ceramic spray powder and a preparation method thereof. Background Art

[0002] Hydrogen production technology is a key development direction in the upstream hydrogen energy industry chain. Water electrolysis can utilize the waste heat of renewable energy as a driving force, facilitating sustainable and pollution-free hydrogen production. The resulting hydrogen is highly pure, has no byproducts, and theoretically achieves zero carbon emissions. Therefore, it offers technical advantages in terms of applicability, environmental benefits, and energy efficiency. The reaction system used for water electrolysis to produce hydrogen typically consists of a cathode, an anode, and an electrolyte. The cathode undergoes the hydrogen evolution reaction (HER), while the anode undergoes the oxygen evolution reaction (OER).

[0003] Lanthanum nickelate ceramics are located near the theoretical activity peak of the OER (Oergine-like) regular curve, and their raw materials are relatively inexpensive, making them commonly used as anode materials for hydrogen electrolysis. Intermediate-entropy ceramics are multicomponent solid solutions formed by doping three or four principal components in near-equimolar ratios. However, there are currently no studies or reports on the intermediate-entropy design of lanthanum nickelate ceramics. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention proposes a B-site doped medium-entropy lanthanum nickelate ceramic spray powder and a preparation method thereof.

[0005] To achieve the above objectives, the present invention provides the following technical solutions:

[0006] The first aspect of the present invention provides a B-doped medium entropy lanthanum nickelate ceramic spray powder, the chemical formula of the B-doped medium entropy lanthanum nickelate ceramic spray powder is: La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3.

[0007] Technical principle: The present invention performs entropy design on the B-site of lanthanum nickelate ceramics and dopes three suitable elements in equal molar ratios into the B-site lattice of lanthanum nickelate ceramics, thereby causing a lattice distortion effect of lanthanum nickelate, increasing its disorder, improving the spraying performance of lanthanum nickelate ceramics, and thus reducing the chamber voltage for electrolysis of water to produce hydrogen.

[0008] The second aspect of the present invention further provides a method for preparing the above-mentioned B-site doped medium-entropy lanthanum nickelate ceramic spray powder, comprising the following steps:

[0009] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3)O3 stoichiometric ratio of weighing La2O3, Ni2O3, Co3O4 and MnO2 powders;

[0010] (2) ball-milling the powder to obtain a ceramic slurry; uniformly stirring the obtained ceramic slurry and gum arabic, and then granulating, sintering and sieving to obtain the B-site doped medium-entropy lanthanum nickelate ceramic spray powder.

[0011] Beneficial effects: The preparation method of the present invention uses the target element oxide as raw material, mixes them by ball milling, and then prepares the B-site doped medium-entropy lanthanum nickelate ceramic spray powder by high-temperature sintering. The sintering process does not require specific atmosphere control and does not require the addition of sintering aids. The process flow is short, the preparation cost is low, and the preparation efficiency is high.

[0012] Furthermore, in step (2), the process conditions for ball milling mixing are: a ball milling speed of 300 rpm, a ball milling time of 12 to 24 hours, anhydrous ethanol and zirconia balls as the ball milling media, and a mass ratio of zirconia balls, ball milling material and anhydrous ethanol of 5:1:5.

[0013] Furthermore, in step (2), the mass ratio of gum arabic to ceramic slurry is 2:100.

[0014] Furthermore, in step (2), the stirring time is 30 minutes.

[0015] Furthermore, in step (2), the air inlet temperature of the granulation is 250-280°C, and the air outlet temperature is 100-150°C.

[0016] Furthermore, in step (2), the atomization speed of the granulation is 280 Hz.

[0017] Furthermore, in step (2), the sintering is as follows: heating from room temperature to 1100-1200° C. at a heating rate of 6° C. / min, keeping the temperature for 3-4 hours, and then cooling to room temperature with the furnace.

[0018] Furthermore, in step (2), the mesh size of the sieve used for sieving is 80 to 100 meshes.

[0019] Compared with the prior art, the present invention has the following advantages and technical effects:

[0020] (1) The preparation process of the present invention is simple, does not require atmosphere sintering, and only requires the use of an ordinary muffle furnace for sintering. It has the characteristics of short sintering time, simple process, low production cost, and high efficiency.

[0021] (2) The present invention prepares La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3)No sintering aid is required during the O3 medium entropy ceramic spraying powder process.

[0022] (3) La(Ni) prepared by the present invention 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 medium entropy ceramic spray powder can reduce the cell voltage by 0.03V when used as anode material after being sprayed onto the optical nickel mesh. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 La(Ni prepared in Example 1 1 / 3 Co 1 / 3 Mn 1 / 3 ) XRD pattern of O3 entropy ceramic powder;

[0025] Figure 2 La(Ni prepared in Example 1 1 / 3 Co 1 / 3 Mn 1 / 3 ) SEM image and element distribution diagram of entropy ceramic powder in O3, wherein a is a SEM image, b is the distribution diagram of La element, c is the distribution diagram of Co element, d is the distribution diagram of Mn element, e is the distribution diagram of Ni element, and f is the distribution diagram of O element;

[0026] Figure 3 The La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) Voltage diagram of the chamber for water electrolysis to produce hydrogen using O3 medium entropy ceramic spray powder-sprayed nickel mesh and pure nickel mesh as anodes. DETAILED DESCRIPTION

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] The embodiment of the present invention discloses a method for preparing a B-site doped medium-entropy lanthanum nickelate ceramic spray powder, which specifically includes the following steps:

[0029] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn1 / 3 )O3 stoichiometric ratio of weighing La2O3, Ni2O3, Co3O4 and MnO2 powders;

[0030] (2) ball-milling the powder to obtain a ceramic slurry; uniformly stirring the obtained ceramic slurry and gum arabic, and then granulating, sintering and sieving to obtain the B-site doped medium-entropy lanthanum nickelate ceramic spray powder.

[0031] In some embodiments, the ball milling conditions in step (2) are as follows: the ball mill speed is 300 rpm, the ball milling time is 12 to 24 hours, the ball milling medium is anhydrous ethanol and zirconia balls, and the mass ratio of zirconia balls, ball milling material, and anhydrous ethanol is 5:1:5. Taking into account the ball milling effect and economic efficiency, the ball milling time can be fully achieved within 12 hours. Therefore, the ball milling time in the following examples is 12 hours.

[0032] In some embodiments, the air inlet temperature of the granulation in step (2) is 250-280° C., and the air outlet temperature is 100-150° C. For example, in some optional embodiments, the air inlet temperature of the granulation is 260° C., and the air outlet temperature is 130° C.; in other optional embodiments, the air inlet temperature of the granulation is 270° C., and the air outlet temperature is 115° C.; in other optional embodiments, the air inlet temperature of the granulation is 280° C., and the air outlet temperature is 145° C.

[0033] In some embodiments, the atomization speed of the high-speed centrifugal spray drying tower during granulation in step (2) is 280 Hz.

[0034] In some embodiments, the mass ratio of gum arabic to ceramic slurry in step (2) is 2:100, and the stirring time is 30 minutes. Gum arabic acts as a binder to bind the mixed powder into agglomerates, facilitating granulation. Gum arabic completely decomposes during high-temperature sintering, leaving no residue and thus avoiding any effect on the ceramic powder.

[0035] In some embodiments, during the sintering process of step (2): the temperature is raised from room temperature to 1100-1200°C at a heating rate of 6°C / min, kept in a muffle furnace for 3-4 hours, and then cooled to room temperature with the furnace. In some optional embodiments, the sintering temperature is 1150°C and the sintering time is 3 hours; in other optional embodiments, the sintering temperature is 1100°C and the sintering time is 3 hours; in other optional embodiments, the sintering temperature is 1200°C and the sintering time is 3.8 hours;

[0036] In some embodiments, the mesh size of the sieve used in step (2) is 80-100 mesh. In some optional embodiments, the mesh size of the sieve is 80 mesh; in other optional embodiments, the mesh size of the sieve is 100 mesh.

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] The room temperature in the embodiments of the present invention refers to "25±2°C".

[0039] Unless otherwise specified, the raw materials in the examples of the present invention were purchased from commercial sources.

[0040] Example 1

[0041] A method for preparing B-site doped medium-entropy lanthanum nickelate ceramic spray powder, comprising the following steps:

[0042] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 in a stoichiometric ratio; the above powders are placed in a ball mill and ball-milled for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and ball milling material (i.e., the above powders) of 5:5:1 at a ball mill speed of 300 rpm to obtain a ceramic slurry; gum arabic is then added to the obtained ceramic slurry and stirred for 30 minutes. The mass ratio of gum arabic to ceramic slurry is 2:100 to obtain a stirred ceramic slurry.

[0043] (2) The stirred ceramic slurry obtained in step (1) is placed in a high-speed centrifugal spray drying tower for granulation, the inlet air temperature of the drying tower is 260°C, the outlet air temperature of the drying tower is 130°C, and the atomization speed of the high-speed centrifugal spray drying tower during granulation is 280Hz to obtain ceramic particles.

[0044] (3) The ceramic particles obtained in step (2) were placed in a crucible, and the crucible was placed in a muffle furnace, and the temperature was increased to 1150°C at a heating rate of 6°C / min, and the temperature was kept in the muffle furnace for 3 hours, and then cooled to room temperature with the furnace, and then the sintered powder was sieved with an 80-mesh sieve to obtain B-doped medium-entropy lanthanum nickelate ceramic spray powder (La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 medium entropy ceramic powder).

[0045] Example 2

[0046] A method for preparing B-site doped medium-entropy lanthanum nickelate ceramic spray powder, comprising the following steps:

[0047] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3)O3 in a stoichiometric ratio; the above powders are placed in a ball mill and ball-milled for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and ball milling material (i.e., the above powders) of 5:5:1 at a ball mill speed of 300 rpm to obtain a ceramic slurry; gum arabic is then added to the obtained ceramic slurry and stirred for 30 minutes. The mass ratio of gum arabic to ceramic slurry is 2:100 to obtain a stirred ceramic slurry.

[0048] (2) The stirred ceramic slurry obtained in step (1) is placed in a high-speed centrifugal spray drying tower for granulation, the inlet air temperature of the drying tower is 270°C, the outlet air temperature of the drying tower is 125°C, and the atomization speed of the high-speed centrifugal spray drying tower during granulation is 280Hz to obtain ceramic particles.

[0049] (3) The ceramic particles obtained in step (2) are placed in a crucible, the crucible is placed in a muffle furnace, and the temperature is increased to 1100° C. at a heating rate of 6° C. / min, and the temperature is kept in the muffle furnace for 3 hours, and then cooled to room temperature with the furnace, and the sintered powder is sieved through a 100-mesh sieve to obtain B-doped medium-entropy lanthanum nickelate ceramic spray powder (La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 medium entropy ceramic powder).

[0050] Example 3

[0051] A method for preparing B-site doped medium-entropy lanthanum nickelate ceramic spray powder, comprising the following steps:

[0052] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 chemical formula, weighing La2O3, Ni2O3, Co3O4 and MnO2 powders in the stoichiometric ratio; placing the above powders into a ball mill, and ball-milling and mixing them for 12 hours at a mass ratio of zirconia balls, anhydrous ethanol and ball milling material (i.e., the above powders) of 5:5:1, with the ball mill speed of 300 rpm, to obtain a ceramic slurry; then adding gum arabic to the obtained ceramic slurry and stirring for 30 minutes, the mass ratio of gum arabic to ceramic slurry being 2:100, to obtain a stirred ceramic slurry.

[0053] (2) The stirred ceramic slurry obtained in step (1) is placed in a high-speed centrifugal spray drying tower for granulation. The air inlet temperature of the drying tower is 280°C, the air outlet temperature of the drying tower is 145°C, and the atomization speed of the high-speed centrifugal spray drying tower during granulation is 280 Hz to obtain ceramic particles.

[0054] (3) The ceramic particles obtained in step (2) were placed in a crucible, and the crucible was placed in a muffle furnace, and the temperature was increased to 1200° C. at a heating rate of 6° C. / min, and the temperature was kept in the muffle furnace for 3.8 hours, and then cooled to room temperature with the furnace, and the sintered powder was sieved with a 100-mesh sieve to obtain B-doped medium-entropy lanthanum nickelate ceramic spray powder (La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 medium entropy ceramic powder).

[0055] Figure 1 La(Ni prepared in Example 1 1 / 3 Co 1 / 3 Mn 1 / 3 ) XRD pattern of the O3 medium-entropy ceramic powder. As can be seen from the figure, the medium-entropy ceramic powder prepared in Example 1 is a single-phase perovskite structure with only extremely small impurity peaks.

[0056] Figure 2 La(Ni prepared in Example 1 1 / 3 Co 1 / 3 Mn 1 / 3 ) SEM image and element distribution diagram of the O3 medium-entropy ceramic powder, where a is the SEM image, b is the distribution diagram of the La element, c is the distribution diagram of the Co element, d is the distribution diagram of the Mn element, e is the distribution diagram of the Ni element, and f is the distribution diagram of the O element. As can be seen from the figure, the element distribution of the medium-entropy ceramic powder prepared in Example 1 is uniform, there is no element segregation, and the sphericity is very good.

[0057] The La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 medium entropy ceramic spray powder is sprayed onto the nickel mesh to obtain lanthanum nickelate sprayed nickel mesh, and the obtained lanthanum nickelate sprayed nickel mesh is used as the anode and the nickel mesh light mesh is used as the cathode to electrolyze water to produce hydrogen (anode lanthanum nickelate sprayed nickel mesh + cathode light mesh); at the same time, a pure nickel mesh light mesh that is not sprayed with medium entropy ceramic spray powder is used as a comparison (anode light mesh + cathode light mesh), and the chamber voltage is tested at a test pressure of 1.2 MPa and an alkali solution temperature of 85°C. The test results are shown in FIG. Figure 3 .

[0058] Figure 3 The La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 entropy ceramic powder sprayed nickel mesh and pure nickel mesh as anodes for electrolysis of water to produce hydrogen. As can be seen from the figure, the La(Ni) prepared in Example 1 1 / 3 Co 1 / 3 Mn 1 / 3)O3 entropy ceramic powder sprayed nickel mesh is used as anode to electrolyze water to produce hydrogen. Compared with pure nickel mesh light mesh, the cell voltage is significantly reduced, and the test current density is from 2000A / m 2 Increased to 10000A / m 2 , the chamber voltage decreased by an average of 0.03V, and the chamber voltage of Examples 2 and 3 decreased by an average of 0.02V, indicating that the B-site doped medium-entropy lanthanum nickelate ceramic spray powder prepared by the present invention can significantly reduce the chamber voltage.

[0059] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for preparing B-site doped medium entropy lanthanum nickelate ceramic spray powder, characterized in that: The following steps are involved: (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 )O3 stoichiometric ratio of weighing La2O3, Ni2O3, Co3O4 and MnO2 powders; (2) ball-milling the powder to obtain a ceramic slurry; uniformly stirring the obtained ceramic slurry and gum arabic, and then granulating, sintering and sieving to obtain the B-site doped medium-entropy lanthanum nickelate ceramic spray powder; the sintering is as follows: heating from room temperature to 1100-1150°C at a heating rate of 6°C / min, keeping the temperature for 3-4 hours, and then cooling to room temperature with the furnace.

2. The method for preparing the B-site doped medium-entropy lanthanum nickelate ceramic spray powder according to claim 1, characterized in that: In step (2), the process conditions for ball milling mixing are: ball milling speed of 300 rpm, ball milling time of 12 to 24 hours, ball milling media of anhydrous ethanol and zirconia balls, and the mass ratio of zirconia balls, ball milling material and anhydrous ethanol is 5:1:

5.

3. The method for preparing the B-site doped medium entropy lanthanum nickelate ceramic spray powder according to claim 1, characterized in that: In step (2), the mass ratio of gum arabic to ceramic slurry is 2:

100.

4. The method for preparing the B-site doped medium-entropy lanthanum nickelate ceramic spray powder according to claim 1, characterized in that: In step (2), the stirring time is 30 minutes.

5. The method for preparing the B-site doped medium entropy lanthanum nickelate ceramic spray powder according to claim 1, characterized in that: In step (2), the air inlet temperature of the granulation is 250-280°C, and the air outlet temperature is 100-150°C.

6. The method for preparing the B-site doped medium entropy lanthanum nickelate ceramic spray powder according to claim 1, characterized in that: In step (2), the atomization speed of the granulation is 280 Hz.

7. The method for preparing the B-site doped medium entropy lanthanum nickelate ceramic spray powder according to claim 1, characterized in that: In step (2), the mesh size of the sieve used for sieving is 80 to 100 meshes.

Images