Preparation method of cobblestone sheet-shaped NaCaLa (MoO4) 3 material with large diameter-thickness ratio
By thermally treating Na2CO3, CaCO3, La2O3, MoO3 and mixed molten salt under air atmosphere, a large diameter and thickness ratio cobblestone sheet-like NaCaLa (MoO4)3 material was prepared, which solved the problems of long calcination time and irregular morphology in the traditional method, and achieved high purity and easy to produce on a large scale.
Patent Information
- Application Number
- CN202510475151.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-16
- Publication Date
- 2025-07-15
AI Technical Summary
It is difficult for the prior art to prepare NaCaLa(MoO4)3 materials with special micromorphic morphology in a short period of time, and the traditional method has a long calcination time and the product morphology is irregular.
Using a new preparation method, Na2CO3, CaCO3, La2O3, MoO3 and mixed molten salt were heat treated at 780-900°C for 1-3 h under an air atmosphere, and then washed with deionized water and filtered to remove the salt components, and a large diameter and thickness ratio cobblestone flakes were prepared.
NaCaLa(MoO4)3 material with significant pebbles flake morphology was prepared in a short period of time. The particle size is much larger than the thickness, good dispersion, high purity, and easy to produce on a large scale.
Smart Images
Figure CN120309012A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of the preparation of inorganic non-metallic materials, and particularly relates to a method for preparing a NaCaLa(MoO4)3 material with a large diameter-thickness ratio, a smooth surface and a pebble-like sheet morphology. Background Art
[0002] Micro-nano materials have been widely used in the fields of materials science, engineering, energy, environment and even medicine due to their unique size effect, enhanced surface area and adjustable properties. Among them, materials with a sheet morphology have special advantages due to their special structure: they have an ultra-large surface area and effective micropore aperture, which can greatly improve the molecular release ability and effect, and modify the surface of the carrier material to optimize the physical, chemical and biological properties. Micro-nano materials with special morphologies usually have excellent unique properties and are widely used in many fields, and thus have attracted extensive attention from scholars at home and abroad. For example, sheet-like molybdenum disulfide performs excellently in the lubrication field. Due to its unique sheet structure, it significantly reduces the friction coefficient and improves the operation efficiency and service life of mechanical equipment; nano-sheet mica powder is added to the coating. With its sheet characteristics of high diameter-thickness ratio, it effectively enhances the barrier performance of the coating, thereby greatly improving the protection ability of the coating; while sheet-like alumina in ceramic matrix composites can be well combined with the matrix and effectively prevent crack propagation after uniform dispersion, thereby significantly improving the strength and toughness of the composite material, making it have broad application prospects in fields with strict requirements for material properties such as aerospace.
[0003] NaCaLa(MoO4)3 belongs to the scheelite structure of the tetragonal system, and the space group is I41 / a. It shows good application value in many fields such as luminescent materials, fuel cells and microwave dielectric ceramics. In view of the special influence of the microscopic morphology structure of the material itself on its physical and chemical properties, exploring the preparation of NaCaLa(MoO4)3 materials with a micro-nano scale sheet structure will change the physical and chemical properties of the material itself while also expanding the application of this material in more other fields.
[0004] At present, the preparation of NaCaLa(MoO4)3 materials at home and abroad mostly adopts the traditional solid-phase method and sol-gel method. The micro-morphology of the NaCaLa(MoO4)3 powder obtained by these methods is generally irregular and the calcination time is relatively long. In the literature "Emerging near-unity internal quantum efficiency and color purity from red-emitting phosphors for warm white LED with enhanced color rendition", it is necessary to calcine at 900 °C for 8 h to obtain the NaCaLa(MoO4)3 doped material. The literature "Triple molybdate scheelite-type upconversion phosphor NaCaLa(MoO4)3:Er 3+ / Yb 3+ :structural and spectroscopicproperties" reported that the NaCaLa(MoO4)3 doped material was obtained by heat treatment at 900 °C for 16 h using the microwave sol-gel method. The above research shows that, so far, there has been no relevant report on the preparation of NaCaLa(MoO4)3 materials with special morphology in a short period. Therefore, the research on the preparation of NaCaLa(MoO4)3 materials with special micro-morphology in a short preparation period has extremely important application prospects; it opens up new ways for its application in more fields and enhances its application value and potential.
[0005] The present invention adopts a new approach to prepare NaCaLa(MoO4)3 materials with a pebble-like flake morphology. The materials prepared by this approach have the advantages of regular particle morphology, good dispersibility, and short preparation period; the preparation method has simple and controllable conditions, simple operation process, and is easy to realize large-scale production. Therefore, the present invention has good application value. Summary of the Invention
[0006] The purpose of the present invention is to provide a NaCaLa(MoO4)3 material with a pebble-like flake morphology having a large diameter-thickness ratio and a preparation method thereof. This method has the advantages of short preparation period, simple preparation process, low process cost, and easy realization of industrial production, and can solve the problems such as long calcination time required for preparing this material by previous methods and no special morphology of the product.
[0007] The technical solution of the present invention is as follows:
[0008] A NaCaLa(MoO4)3 material with a pebble-like flake morphology having a large diameter-thickness ratio and a preparation method thereof, comprising the following steps:
[0009] (1) Weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials in a molar ratio of 1:2:1:6, and then add a mixed molten salt. Mix and grind to obtain a precursor. Among them, the content of NaCl in the mixed molten salt is 48%, and the content of CaCl2 is 52%.
[0010] (2) Transfer the precursor obtained in step (1) to a muffle furnace and perform heat treatment in an air atmosphere. After the calcination time ends, naturally cool to obtain a mixed product.
[0011] (3) Wash the mixture obtained in step (2) with deionized water multiple times, filter to remove the salt components, and dry to obtain a material with a large diameter-thickness ratio and a pebble-like flake morphology of NaCaLa(MoO4)3.
[0012] Furthermore, in step (1), the molar ratio of the raw materials to the mixed molten salt is Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:(6 - 30).
[0013] Furthermore, in step (2), the calcination temperature is 780 - 900 °C.
[0014] Furthermore, in step (2), the calcination time is 1 - 3 h.
[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0016] 1. The present invention adopts a new preparation method and prepares a material with a large diameter-thickness ratio and a pebble-like flake morphology of NaCaLa(MoO4)3 at 800 °C. Compared with the traditional solid-phase method, this method reduces the preparation cycle of the material.
[0017] 2. The NaCaLa(MoO4)3 material prepared by the present invention has a significant pebble-like flake morphology, the particle size is much larger than its thickness, and it has good dispersibility.
[0018] 3. The preparation method of the present invention is simple, the conditions are mild and easy to control, the prepared material has high purity and excellent micro-morphology, and it is easy to realize large-scale production. Description of the Drawings
[0019] Figure 1 XRD pattern of the NaCaLa(MoO4)3 material prepared in Example 1.
[0020] Figure 2 XRD pattern of the NaCaLa(MoO4)3 material prepared in Example 2; where a is the XRD pattern of the sample at 780 °C, b is the XRD pattern of the sample at 850 °C, and c is the XRD pattern of the sample at 900 °C.
[0021] Figure 3 XRD patterns of the NaCaLa(MoO4)3 material prepared in Example 3; among them, d is the XRD pattern with a calcination time of 3 h, and e is the XRD pattern with a calcination time of 1 h.
[0022] Figure 4 XRD patterns of the NaCaLa(MoO4)3 material prepared in Example 4, f is the XRD pattern with a mixed molten salt ratio of 6, and g is the XRD pattern with a mixed molten salt ratio of 30.
[0023] Figure 5 、 6 SEM images of the NaCaLa(MoO4)3 material prepared in Example 1.
[0024] Figure 7 SEM images of the material prepared in Example 2, where (A) and (B) are SEM images of samples with calcination temperatures of 850 °C and 900 °C, respectively.
[0025] Figure 8 SEM images of the material prepared in Comparative Example 1, where (A) and (B) are SEM images of samples with calcination temperatures of 700 °C and 750 °C, respectively. Detailed implementation manners
[0026] The following further illustrates the detailed implementation manners of the present invention in conjunction with the accompanying drawings and technical solutions.
[0027] Example 1:
[0028] Weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials according to the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:18. Separately take an appropriate amount of the mixed molten salt and mix it with the above raw materials and grind for 12 min to obtain a precursor; transfer the precursor to a muffle furnace and perform heat treatment in an air atmosphere. The calcination temperature is 800 °C and the calcination time is 2 h. After the calcination time ends, let it cool naturally to obtain a NaCaLa(MoO4)3-salt mixture; wash the obtained NaCaLa(MoO4)3-salt mixture with deionized water multiple times and filter to remove the salt components, and dry it at 108 °C for 2.3 h to obtain the NaCaLa(MoO4)3 powder material.
[0029] Example 2:
[0030] The difference between this example and Example 1 is that the calcination temperatures are 780 °C, 850 °C, and 900 °C respectively. The specific implementation process is as follows:
[0031] According to the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:18, weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials respectively. Another appropriate amount of mixed molten salt is taken and mixed with the above raw materials and ground for 12 min to obtain a precursor; transfer the precursor to a muffle furnace and perform heat treatment in an air atmosphere. The calcination temperature is 780 °C and the calcination time is 2 h. After the calcination time ends, it is naturally cooled to obtain a NaCaLa(MoO4)3-salt mixture; wash the obtained NaCaLa(MoO4)3-salt mixture with deionized water multiple times and filter to remove the salt components, and dry it at 108 °C for 2.3 h to obtain the NaCaLa(MoO4)3 powder material.
[0032] The preparation steps are the same as above, only changing the calcination temperatures to 850 °C and 900 °C respectively, and two more NaCaLa(MoO4)3 powder materials are prepared.
[0033] Example 3:
[0034] The differences between this example and Examples 1 and 2 are as follows: the calcination times at 800 °C are 3 h and 1 h respectively. The specific implementation process is as follows:
[0035] According to the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:18, weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials respectively. Another appropriate amount of mixed molten salt is taken and mixed with the above raw materials and ground for 12 min to obtain a precursor; transfer the precursor to a muffle furnace and perform heat treatment in an air atmosphere. The calcination temperature is 800 °C and the calcination time is 3 h. After the calcination time ends, it is naturally cooled to obtain a NaCaLa(MoO4)3-salt mixture; wash the obtained NaCaLa(MoO4)3-salt mixture with deionized water multiple times and filter to remove the salt components, and dry it at 108 °C for 2.3 h to obtain the NaCaLa(MoO4)3 powder material.
[0036] The preparation steps are the same as above, only changing the calcination time to 1 h, and another NaCaLa(MoO4)3 powder material is prepared.
[0037] Example 4:
[0038] The differences between this example and Examples 1, 2, and 3 are as follows: the molar ratios of the raw materials are Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:(30 and 6) respectively. The specific implementation process is as follows:
[0039] According to the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:30, weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials respectively. Take an appropriate amount of mixed molten salt and mix it with the above raw materials and grind for 12 min to obtain a precursor; transfer the precursor to a muffle furnace and conduct heat treatment in an air atmosphere. The calcination temperature is 850 °C and the calcination time is 2 h. After the calcination time ends, naturally cool to obtain a NaCaLa(MoO4)3-salt mixture; wash the obtained NaCaLa(MoO4)3-salt mixture with deionized water multiple times and filter to remove the salt components, and dry at 108 °C for 2.3 h to obtain the NaCaLa(MoO4)3 powder material.
[0040] The preparation steps are the same as above, only changing the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:6, and another NaCaLa(MoO4)3 powder material is prepared.
[0041] Comparative Example 1:
[0042] The differences between this comparative example and Examples 1-4 are: the calcination temperatures are 700 °C, 750 °C, and 910 °C respectively. The specific implementation process is as follows:
[0043] According to the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:18, weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials respectively. Take an appropriate amount of mixed molten salt and mix it with the above raw materials and grind for 12 min to obtain a precursor; transfer the precursor to a muffle furnace and conduct heat treatment in an air atmosphere. The calcination temperature is 700 °C and the calcination time is 2 h. After the calcination time ends, naturally cool to obtain a NaCaLa(MoO4)3-salt mixture; wash the obtained NaCaLa(MoO4)3-salt mixture with deionized water multiple times and filter to remove the salt components, and dry at 108 °C for 2.3 h to obtain the NaCaLa(MoO4)3 powder material.
[0044] The preparation steps are the same as above, only changing the calcination temperatures to 750 °C and 910 °C respectively, and two more NaCaLa(MoO4)3 powder materials are prepared.
[0045] Observed by SEM, it was found that the samples at 700 °C and 750 °C in Example 5 did not obtain good large aspect ratio pebble-like sheet materials, and the sample at 910 °C was slightly worse with a coexistence of particles and sheet materials.
[0046] Comparative Example 2:
[0047] The differences between this comparative example and Examples 1-5 are as follows: The calcination times at 850 °C are 3.1 h and 0.9 h respectively. The specific implementation process is as follows:
[0048] Weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials respectively according to the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:18. Another appropriate amount of mixed molten salt is taken and mixed with the above raw materials and ground for 12 min to obtain a precursor; the precursor is transferred to a muffle furnace and heat-treated in an air atmosphere. The calcination temperature is 850 °C and the calcination time is 3.1 h. After the calcination time ends, it is naturally cooled to obtain a NaCaLa(MoO4)3-salt mixture; the obtained NaCaLa(MoO4)3-salt mixture is washed with deionized water multiple times and filtered to remove the salt components, and dried at 108 °C for 2.3 h to obtain the NaCaLa(MoO4)3 powder material.
[0049] The preparation steps are the same as above, only changing the calcination time to 0.9 h, and another NaCaLa(MoO4)3 powder material is prepared.
[0050] Observed by SEM, it is found that neither of the two samples in Example 6 obtained good cobblestone flake materials, and the samples are both in a situation where particles and fragmented materials coexist.
[0051] Comparative Example 3:
[0052] The differences between this comparative example and Examples 1-6 are as follows: The molar ratios of the raw materials are Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:(36.6 and 5.4) respectively. The specific implementation process is as follows:
[0053] Weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials respectively according to the molar ratio of Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:36.6. Another appropriate amount of mixed molten salt is taken and mixed with the above raw materials and ground for 12 min to obtain a precursor; the precursor is transferred to a muffle furnace and heat-treated in an air atmosphere. The calcination temperature is 800 °C and the calcination time is 2 h. After the calcination time ends, it is naturally cooled to obtain a NaCaLa(MoO4)3-salt mixture; the obtained NaCaLa(MoO4)3-salt mixture is washed with deionized water multiple times and filtered to remove the salt components, and dried at 108 °C for 2.3 h to obtain the NaCaLa(MoO4)3 powder material.
[0054] The preparation steps are the same as above. Change Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:5.4, and calcine at 850 °C for 2 h to obtain another NaCaLa(MoO4)3 powder material.
[0055] Observed by SEM, it was found that good pebble-like materials were not obtained for both samples in Example 7, and the samples were both in a situation where particles and fragmented materials coexisted.
[0056] Figures 1-4 XRD patterns of the NaCaLa(MoO4)3 materials prepared in Examples 1-4. It can be seen from the XRD patterns that the diffraction peaks are high, indicating that a NaCaLa(MoO4)3 material with high crystallinity is formed.
[0057] Figures 5-7 SEM images of the NaCaLa(MoO4)3 materials prepared in Examples 1-4. It can be seen from these SEM images that pebble-like NaCaLa(MoO4)3 materials are obtained, and the diameter of the pebble-like shape is much larger than its thickness.
[0058] Figure 8 SEM images of the materials prepared in Comparative Example 1. It can be seen from these SEM images that good pebble-like materials with a large diameter-thickness ratio were not obtained for the samples at 700 °C and 750 °C.
[0059] The above has shown and described the basic principles and main features of the present invention. However, the above are only specific implementation cases of the present invention, and the technical features of the present invention are not limited thereto. Any changes and modifications made within the scope of the patent application of the present invention shall fall within the scope covered by the present invention.
Claims
1. A preparation method of a NaCaLa(MoO4)3 material with a large diameter-thickness ratio and a pebble-like flake morphology, characterized in that, It includes the following steps: (1) Weigh Na2CO3, CaCO3, La2O3, and MoO3 as raw materials according to the molar ratio of 1:2:1:6, and then add a mixed molten salt. Mix and grind to obtain a precursor. Among them, the content of NaCl in the mixed molten salt is 48%, and the content of CaCl2 is 52%. (2) Transfer the precursor obtained in step (1) to a muffle furnace and conduct heat treatment in an air atmosphere. After the calcination time ends, naturally cool to obtain a mixed product. (3) Wash the mixture obtained in step (2) with deionized water multiple times, filter to remove the salt components, and dry to obtain the material of NaCaLa(MoO4)3 with a large diameter-thickness ratio and pebble-like morphology.
2. The preparation method according to claim 1, characterized in that, In step (1), the molar ratio of the raw materials to the mixed molten salt is Na2CO3:CaCO3:La2O3:MoO3:mixed molten salt = 1:2:1:6:(6 - 30).
3. The preparation method according to claim 1, wherein, In step (2), the heat treatment temperature is 780 - 900 °C, and the calcination time is 1 - 3 h.