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

Abstract

The invention discloses B-site doped medium-entropy lanthanum nickelate ceramic spraying powder and a preparation method thereof, and belongs to the technical field of spraying materials. The chemical formula of the B-site doped medium-entropy lanthanum nickelate ceramic spraying powder provided by the invention is La (Ni < 1 / 3 > Co < 1 / 3 > Mn < 1 / 3 >) O < 3 >. According to the method, the lanthanum nickelate ceramic is subjected to B-bit middle entropy design, and three suitable elements are doped into B-bit crystal lattices of the lanthanum nickelate ceramic according to the equal molar ratio, so that the distortion effect of the lanthanum nickelate crystal lattices is caused, the confusion degree of the lanthanum nickelate crystal lattices is increased, the spraying performance of the lanthanum nickelate ceramic is improved, and then the cell voltage of hydrogen production through water electrolysis is reduced. After the La (Ni1 / 3Co1 / 3Mn1 / 3) O3 medium-entropy ceramic powder provided by the invention is sprayed to a nickel net, the voltage of a small chamber for producing hydrogen by electrolyzing water is averagely reduced by 0.03 v compared with that of a light net and a nickel net, and the advantages of energy conservation, environmental protection and the like are achieved.

Description

Technical Field

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

[0002] Hydrogen production technology is the key development direction of the upstream hydrogen energy industry chain. Among them, water electrolysis can use the waste heat of renewable energy as a driving force, which is convenient for sustainable and pollution-free hydrogen production. The produced hydrogen is of high purity and has no by-products. In theory, it can achieve zero carbon emissions. Therefore, it has technical advantages in terms of applicability, environmental benefits and energy efficiency. The reaction system for water electrolysis to produce hydrogen usually consists of three parts: cathode, anode and electrolyte. The cathode undergoes hydrogen evolution reaction (HER) and the anode undergoes oxygen evolution reaction (OER).

[0003] Lanthanum nickel oxide ceramics are located near the theoretical activity top in the OER volcano-type regular curve, and the raw material price is relatively low, so they are often used as anode materials for electrolysis of water to produce hydrogen. Medium-entropy ceramic materials are multi-component solid solution ceramics formed by doping 3-4 main elements in nearly equimolar proportions. However, there is no research or report on the medium-entropy design of lanthanum nickel oxide 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 object, 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, wherein 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 ) 3 .

[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 thereby reducing the chamber voltage for electrolysis of water to produce hydrogen.

[0008] The second aspect of the present invention also 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 )3 Weigh La in the stoichiometric ratio 2 O 3 、Ni 2 O 3 、Co 3 O 4 and MnO 2 powder;

[0010] (2) ball-milling the above powders to obtain ceramic slurry; stirring the obtained ceramic slurry and gum arabic uniformly, 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: 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, ball milling material and anhydrous ethanol is 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 inlet air temperature of the granulation is 250-280°C, and the outlet air 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: 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 in 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) Preparation of La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 No sintering aids are required during the medium entropy ceramic spraying powder process.

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

[0023] The accompanying drawings constituting a part of the present invention are used 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 improper limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 The La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 XRD pattern of medium entropy ceramic powder;

[0025] Figure 2 The La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 SEM image and element distribution map of medium entropy ceramic powder, where a is the SEM image, b is the distribution map of La element, c is the distribution map of Co element, d is the distribution map of Mn element, e is the distribution map of Ni element, and f is the distribution map of O element;

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

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work 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 comprises the following steps:

[0029] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 Weigh La in the stoichiometric ratio 2 O 3 、Ni 2 O 3 、Co 3 O 4 and MnO 2 powder;

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

[0031] In some embodiments, the conditions for ball milling in step (2) are: the speed of the ball mill is 300 rpm, the ball milling time is 12 to 24 hours, the ball milling medium is anhydrous ethanol and zirconium oxide balls, and the mass ratio of zirconium oxide balls, ball milling material and anhydrous ethanol is 5:1:5. Considering the ball milling effect and economy, the purpose of sufficient ball milling can be achieved when the ball milling is 12 hours, so the ball milling time in the following embodiments is taken as 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. The role of gum arabic is to act as a binder to bind the mixed powder into a mass, which is convenient for granulation. Gum arabic can be completely decomposed during high-temperature sintering without residue, thereby avoiding the influence on 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 to 100 meshes. In some optional embodiments, the mesh size of the sieve is 80 meshes; in other optional embodiments, the mesh size of the sieve is 100 meshes.

[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, the specific steps are as follows:

[0042] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 Weigh La in the stoichiometric ratio 2 O 3 、Ni 2 O 3 、Co 3 O 4 and MnO 2 Powder; putting the above powder into a ball mill, and mixing the zirconium oxide balls, anhydrous ethanol and ball milling material (i.e. the above powder) in a mass ratio of 5:5:1 for 12 hours at a 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 the ceramic slurry is 2:100 to obtain a stirred ceramic slurry.

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

[0044] (3) placing the ceramic particles obtained in step (2) in a crucible, placing the crucible in a muffle furnace, heating the crucible to 1150° C. at a heating rate of 6° C. / min, and keeping the temperature in the muffle furnace for 3 hours, then cooling the crucible to room temperature, and then passing the sintered powder through an 80-mesh sieve to obtain a B-doped medium-entropy lanthanum nickelate ceramic spray powder (La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 Medium entropy ceramic powder).

[0045] Example 2

[0046] A method for preparing B-site doped medium entropy lanthanum nickelate ceramic spray powder, the specific steps are as follows:

[0047] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 Weigh La in the stoichiometric ratio 2 O 3 、Ni 2 O 3 、Co 3 O 4 and MnO 2 Powder; putting the above powder into a ball mill, and mixing the zirconium oxide balls, anhydrous ethanol and ball milling material (i.e. the above powder) in a mass ratio of 5:5:1 for 12 hours at a 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 the ceramic slurry is 2:100 to obtain a stirred ceramic slurry.

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

[0049] (3) placing the ceramic particles obtained in step (2) in a crucible, placing the crucible in a muffle furnace, heating the crucible to 1100° C. at a heating rate of 6° C. / min, and keeping the temperature in the muffle furnace for 3 hours, then cooling the crucible to room temperature, and then passing the sintered powder through a 100-mesh sieve to obtain a B-doped medium-entropy lanthanum nickelate ceramic spray powder (La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 Medium entropy ceramic powder).

[0050] Example 3

[0051] A method for preparing B-site doped medium entropy lanthanum nickelate ceramic spray powder, the specific steps are as follows:

[0052] (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 Stoichiometric weighing La in chemical formula 2 O 3 、Ni 2 O 3 、Co 3 O 4 and MnO 2 powder; putting the above powder into a ball mill, and mixing the zirconium oxide balls, anhydrous ethanol and ball milling material (i.e. the above powder) in a mass ratio of 5:5:1 for 12 hours at a 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 the ceramic slurry is 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) placing the ceramic particles obtained in step (2) in a crucible, placing the crucible in a muffle furnace, heating the crucible to 1200° C. at a heating rate of 6° C. / min, and keeping the temperature in the muffle furnace for 3.8 hours, then cooling the crucible to room temperature, and then passing the sintered powder through a 100-mesh sieve to obtain a B-doped medium-entropy lanthanum nickelate ceramic spray powder (La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 Medium entropy ceramic powder).

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

[0056] Figure 2 The La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) 3 SEM image and element distribution diagram of medium entropy ceramic powder, where a is the 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. It can be seen from the figure that 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 ) 3 The medium entropy ceramic spray powder was sprayed onto the nickel mesh to obtain a lanthanum nickelate sprayed nickel mesh. The obtained lanthanum nickelate sprayed nickel mesh was used as the anode and the nickel mesh optical mesh was used as the cathode to electrolyze water to produce hydrogen (anode lanthanum nickelate sprayed nickel mesh + cathode optical mesh); at the same time, a pure nickel mesh optical mesh without the medium entropy ceramic spray powder was used as a comparison (anode optical mesh + cathode optical mesh), and the chamber voltage was tested. The test pressure was 1.2MPa and the alkali solution temperature was 85°C. The test results are shown in Figure 3 .

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

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

Claims

1. A B-doped medium entropy lanthanum nickelate ceramic spray powder, characterized in that: 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.

2. A method for preparing the B-site doped medium entropy lanthanum nickelate ceramic spray powder according to claim 1, characterized in that: The following steps are involved: (1) According to La(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 ) Weigh La2O3, Ni2O3, Co3O4 and MnO2 powders in a stoichiometric ratio of 1:1 to 2:1; (2) ball-milling the above powders to obtain ceramic slurry; stirring the obtained ceramic slurry and gum arabic uniformly, and then granulating, sintering and sieving to obtain the B-site doped medium entropy lanthanum nickelate ceramic spray powder.

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

5.

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

100.

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

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

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

8. The method for preparing the B-site doped medium entropy lanthanum nickelate ceramic spray powder according to claim 2, characterized in that: 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 in the furnace.

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

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