WO2022120712A1 - Size-controllable aerogel ball and preparation method and application thereof - Google Patents

Size-controllable aerogel ball and preparation method and application thereof Download PDF

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WO2022120712A1
WO2022120712A1 PCT/CN2020/135250 CN2020135250W WO2022120712A1 WO 2022120712 A1 WO2022120712 A1 WO 2022120712A1 CN 2020135250 W CN2020135250 W CN 2020135250W WO 2022120712 A1 WO2022120712 A1 WO 2022120712A1
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aerogel
controllable
filler
size
slurry
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PCT/CN2020/135250
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French (fr)
Chinese (zh)
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么依民
孙蓉
曾小亮
任琳琳
张涛
许建斌
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中国科学院深圳先进技术研究院
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Priority to PCT/CN2020/135250 priority Critical patent/WO2022120712A1/en
Publication of WO2022120712A1 publication Critical patent/WO2022120712A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B21/00—Nitrogen; Compounds thereof
    • C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
    • C01B21/064—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with boron
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B21/00—Nitrogen; Compounds thereof
    • C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
    • C01B21/072—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with aluminium
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/90—Carbides
    • C01B32/914—Carbides of single elements
    • C01B32/956—Silicon carbide
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G9/00—Compounds of zinc
    • C01G9/02—Oxides; Hydroxides

Definitions

  • the invention belongs to the technical field of nano-porous materials, and in particular relates to a size-controllable aerogel ball and a preparation method and application thereof.
  • aerogel spheres As a new type of porous material, aerogel spheres have broad application prospects in the fields of energy storage, sensors, biological tissue engineering and environmental protection due to their large specific surface area, ordered microstructure and tunable pore size. has received extensive attention in recent years. At the same time, aerogel spheres can also be used as a thermal conductive filler. Aerogel spheres are essentially aerogels, which can form a macroscopic three-dimensional thermal conduction network after being interconnected to improve the thermal conductivity of composite materials. How to effectively control the regularity and size has always been a key technical issue in the preparation of aerogel spheres. The microstructure of aerogel spheres is related to the assembly technique and the morphology of the assembled unit. Although the preparation technology of aerogel has developed rapidly in the past decade, there are still several problems as follows:
  • the technical processes for preparing porous spheres mainly include template method, liquid-liquid phase injection, and water/solvothermal.
  • the above three methods all have certain disadvantages, such as low yield and complicated preparation process, which limit their practical application.
  • monodispersed silica or polyester microspheres are usually used as templates for preparing porous hollow spheres, and then the precursor of the target product is covered on the surface of the template, and the precursor is removed after the reaction is completed.
  • the preparation process is complicated.
  • the purpose of the present invention is to overcome the above-mentioned deficiencies of the prior art, and provide a general method for preparing size-controllable aerogel spheres, which is widely applicable to zero-dimensional particles, one-dimensional tubes /Linear materials and two-dimensional materials are not limited by material types and morphology, and the method solves the technical bottleneck of narrow applicable material range, complex preparation process and low yield of existing common methods.
  • a first aspect of the present invention provides a method for preparing a size-controllable aerogel ball, comprising the following steps:
  • Step 1 Mix filler, viscosity modifier, salt and water according to the mass ratio of 1:(0.05-0.2):(0.025-0.05):(5-50) to obtain functionalized filler slurry;
  • Step 2 Put the functionalized filler slurry into the electrospray treatment device, and collect the filler slurry droplets with controllable diameters through the collection device;
  • Step 3 dropping droplets of the filler slurry with a controllable diameter into a low-temperature refrigeration medium, performing freezing treatment to form a frozen mixture, and subjecting the frozen mixture to freeze-drying treatment to obtain aerogel sphere precursors;
  • Step 4 Perform the first and second sintering heat treatments on the aerogel sphere precursor to obtain aerogel spheres.
  • the filler is selected from any material that does not chemically react with water at room temperature, but is not limited to aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide , at least one of graphene.
  • the target filler does not chemically react with water and can be dispersed in water, it can be prepared into aerogel spheres based on the method of the present invention.
  • the filler is selected from, but not limited to, any one of particles, lines or sheets, or any combination thereof. Any one of particles, threads or sheets, or any combination thereof can be prepared into aerogel spheres based on the method of the present invention.
  • the particle size of the filler is 50 nm ⁇ 100 ⁇ m.
  • the viscosity control agent is selected from at least one of sodium carboxymethyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose or hydroxyethyl cellulose.
  • the selection of these viscosity modifiers can effectively improve the dispersibility of the filler in water, avoid the agglomeration of the filler, and improve the mechanical properties of the aerogel sphere precursor to facilitate subsequent sintering heat treatment.
  • the salt is selected from at least one of sodium chloride, sodium sulfate, potassium chloride, potassium sulfate or potassium nitrate.
  • the addition of salt can improve the conductivity of the filler slurry so that the electric field force acts on the filler slurry droplets.
  • the mixing treatment adopts a planetary mixer to stir, and after mixing the filler, viscosity modifier, salt and water according to a certain mass ratio, a uniform filler dispersion liquid in a short time is obtained.
  • the mixing treatment is performed by a planetary mixer, and the rotation speed of the planetary mixer is 20-80 rpm, and the time is 0.2-5 h.
  • the mixing process is processed by a planetary mixer, and the speed and time of the planetary mixer are controlled, so that the filler slurry system is stable and the filler is uniformly dispersed.
  • the electrospray treatment device is mainly used to introduce an electric field between the injection end of the filler slurry and the collection device, the distance between the injection end of the filler slurry and the collection device is 10-50 cm, and the filler slurry
  • the voltage difference between the material ejection end and the collecting device is 2-25kV, and the diameter of the slurry droplet is 9 ⁇ m-2.7mm.
  • the EFI treatment device is equipped with an automatic propulsion device, and the propulsion rate is 0.1-10 cm/min.
  • the propulsion rate can control the yield and morphology yield of the aerogel spheres.
  • the cryogenic refrigeration medium is at least one of liquid nitrogen or liquid helium
  • the freezing treatment is to drop the filler slurry droplets on the surface of the low-temperature refrigeration medium, thereby triggering a continuous self-assembly molding process, and the freezing time is 2-30s, in order to make the slurry droplets droplets
  • the water in it freezes and orients the filler radially.
  • the vacuum degree of the freeze-drying treatment is -15Pa ⁇ -50Pa
  • the freezing temperature is -45°C ⁇ 20°C
  • the freezing time is 2h ⁇ 6h.
  • the first sintering temperature is 350°C-400°C, and the sintering time is 4h-6h; the second sintering temperature is 800°C-1800°C, and the sintering time is 6h-12h.
  • the second aspect of the present invention provides an aerogel ball
  • the aerogel ball is prepared by the preparation method of the present invention
  • the specific surface area of the aerogel ball is 50m 2 /g ⁇ 250m 2 / g
  • the density of the aerogel balls is 20 mg/cm 3 to 200 mg/cm 3
  • the porosity of the aerogel balls is 74% to 96%
  • the diameter of the aerogel balls is 10 ⁇ m to 3.0 mm .
  • the third aspect of the present invention provides the application of the aerogel balls prepared by the general method of the present invention for preparing size-controllable aerogel balls in the fields of environmental protection, energy storage, composite materials, military and aerospace.
  • the present invention has the following beneficial effects:
  • the general method of the present invention for preparing size-controllable aerogel spheres mixes fillers, viscosity modifiers, salts and water to form functionalized filler slurry, and controls the diameter of the filler slurry droplets through an electrospray control device , the slurry droplets only need to undergo freezing treatment, freeze drying and sintering heat treatment, so that the method has a wide range of applicable materials, controllable aerogel size, simple preparation process, relatively mild reaction conditions and high yield.
  • the technical bottleneck of the existing conventional methods such as narrow applicable material range, complicated preparation process and low yield is solved, and the application prospect of the aerogel spheres in various fields is broadened.
  • the prepared aerogel spheres have a large specific surface area, low density, high porosity, a hierarchical three-dimensional structure, a unique radial shape, and a microscopic morphology similar to sea urchins.
  • the diameter of the aerogel spheres can be precisely controlled.
  • the specific surface area of the prepared aerogel spheres is 200 m 2 /g
  • the density of the aerogel spheres is 150 mg/cm 3
  • the The porosity of the gel spheres was 88%
  • the diameter of the aerogel spheres was 200 ⁇ m. Therefore, the aerogel spheres of the embodiments of the present invention have large specific surface area, low density, high porosity, and the size can be precisely controlled.
  • the aerogel balls prepared by the method of the present invention have excellent comprehensive structural properties and controllability, so they can be more widely used in the fields of environmental protection, energy storage, composite materials, military and aerospace fields.
  • FIG. 1 is a flow chart of a preparation method of a method for preparing size-controllable aerogel spheres commonly used in an embodiment of the present invention
  • FIG. 2 is an explanatory diagram of an electrospray control device for a method for preparing size-controllable aerogel balls commonly used in an embodiment of the present invention
  • Example 3 is an explanatory diagram of the molding process of the boron nitride micro-sheet aerogel ball prepared in Example 1;
  • Fig. 4 is the scanning electron microscope (SEM) image of the boron nitride microplate aerogel sphere prepared in Example 1;
  • FIG. 5 is a scanning electron microscope (SEM) image of the silicon carbide nanowire aerogel spheres prepared in Example 2.
  • SEM scanning electron microscope
  • the present invention provides a general method for preparing size-controllable aerogel spheres.
  • the general process steps of the method for preparing size-controllable aerogel balls of the present invention are shown in Figure 1, which includes the following steps:
  • Perform sintering heat treatment on the aerogel precursor perform the first and second sintering heat treatments on the aerogel sphere precursor to obtain aerogel spheres.
  • FIG. 2 is an explanatory diagram of the electrospray control equipment of the method for preparing size-controllable aerogel balls in general according to the present invention, which mainly includes an ultrasonic generator, a syringe, a mobile platform, a glass cover, a collection bin and a separation baffle. Among them, the syringe is placed on the mobile platform, and the two sides of the syringe are equipped with ultrasonic generators.
  • the injection section of the syringe is connected to the electrode. After the droplets are dropped, they fall into the collection bin below through the glass cover, and are screened by the dividing baffle and stored. Specifically, the injection end of the syringe is connected to a high voltage, and the collection chamber is grounded, so there is an electric field of a certain strength between the injection end and the collection chamber.
  • the functionalized filler slurry will be affected by the electric field force in the electric field. When the sum of the electric field force and the gravity is greater than the sum of the surface tension and the adhesion force of the filler slurry droplet, the filler slurry droplet will drip.
  • the electric field strength between the injection section and the collection chamber can be changed by changing the distance and the voltage difference between the injection section and the collection chamber, so as to control the electric field force on the filler slurry droplets and regulate the flow rate of the filler slurry droplets. Final diameter.
  • the following embodiments of the present invention further provide several aerogel sphere materials.
  • these several aerogel ball materials are prepared by using the above general method for preparing aerogel balls with controllable size. Specifically include the following embodiments:
  • the preparation method of the boron nitride microchip aerogel ball provided in Example 1 includes the following specific steps:
  • the boron nitride microflake aerogel spheres prepared in Example 1 of the present invention were analyzed macroscopically and microscopically. 10-40 ⁇ m, and it can be seen that the boron nitride microplates are connected to each other to form a porous structure.
  • the specific surface area of the obtained boron nitride microplate aerogel spheres is 200 m 2 /g, the density of the aerogel spheres is 150 mg/cm 3 , the porosity of the aerogel spheres is 88%, and the diameter of the aerogel spheres is 200 ⁇ m.
  • the preparation method of the silicon carbide nanowire aerogel ball provided in Example 2 is shown in FIG. 1, including the following specific steps:
  • S21 Mix silicon carbide nanowires with a diameter of 200 nm and a length of 10 ⁇ m, hydroxypropyl methylcellulose, potassium chloride and water according to a mass ratio of 1:0.05:0.05:20, and then stir in a planetary mixer for 3 hours, and the stirring speed is 60 rpm to obtain functionalized silicon carbide nanowire slurry;
  • the silicon carbide nanowire aerogel sphere precursor is subjected to a sintering heat treatment process, the first sintering heat treatment temperature is 390°C, and the sintering time is 5h; the second sintering temperature is 1000°C, and the sintering time is 4h.
  • the nanowire aerogel spheres prepared in Example 2 of the present invention were analyzed macroscopically and microscopically.
  • the surface of silicon carbide nanowire aerogel spheres has macroscopic-sized pores.
  • the specific surface area of the above-mentioned silicon carbide nanowire aerogel ball is 220 m 2 /g, the density of the aerogel ball is 70 mg/cm 3 , the porosity of the aerogel ball is 95%, and the aerogel ball has a porosity of 95%.
  • the diameter of the ball is 115 ⁇ m.
  • the preparation method of the alumina particle aerogel ball provided in Example 3 includes the following specific steps:
  • Alumina particles with a size of 40 ⁇ m, hydroxyethyl cellulose, sodium sulfate and water are mixed in a mass ratio of 1:0.15:0.03:5, and then stirred in a planetary mixer for 2 hours at a stirring speed of 50 rpm to obtain functionalized oxidized Aluminum particle slurry;
  • the alumina particle aerogel ball precursor is subjected to a sintering heat treatment process, the first sintering heat treatment temperature is 350°C, and the sintering time is 2h; the second sintering temperature is 1200°C, and the sintering time is 5h.
  • the alumina particle aerogel spheres prepared in Example 3 of the present invention were subjected to macroscopic and microscopic analysis.
  • the specific surface area of the above alumina particle aerogel spheres is 70m 2 /g
  • the density of the aerogel spheres is 310mg/cm 3
  • the porosity of the aerogel spheres is 77%
  • the aerogel spheres The diameter is 2.45mm.
  • the preparation method of the zinc oxide particle aerogel ball provided in Example 4 is shown in Figure 1, and includes the following specific steps:
  • the zinc oxide particle aerogel ball precursor is subjected to a sintering heat treatment process, the first sintering heat treatment temperature is 350°C, and the sintering time is 3h; the second sintering temperature is 800°C, and the sintering time is 6h.
  • the zinc oxide particle aerogel spheres prepared in Example 4 of the present invention were subjected to macroscopic and microscopic analysis.
  • the specific surface area of the above-mentioned zinc oxide particle aerogel balls is 53 m 2 /g, the density of the aerogel balls is 350 mg/cm 3 , the porosity of the aerogel balls is 74%, and the aerogel balls The diameter is 2.67mm.

Abstract

The present invention belongs to the technical field of nanoporous materials, and discloses size-controllable aerogel balls and a preparation method thereof and application thereof. The method for preparing aerogel balls of the present invention comprises the following steps: mixing a filler, a viscosity index improver, salt, and water in accordance with the mass ratio of 1:0.05–0.2:0.025–0.05:5–50 to obtain a functionalized filler slurry; placing the functionalized filler slurry into an electrospray treatment unit to obtain filler slurry droplets of controlled diameter; then dropping into a low-temperature cooling medium, freezing to form a frozen mixture, and freeze-drying to obtain an aerogel ball precursor; subjecting the aerogel ball precursor to first and second sintering heat treatment to obtain aerogel balls. The present invention has a broad range of applicable materials, controllable aerogel size, a simple preparation process, relatively mild reaction conditions, and high yield; the diameter of the aerogel balls is controllable, porosity is high, and the invention has good prospects for application in many fields.

Description

一种尺寸可控的气凝胶球及其制备方法和应用A size-controllable aerogel ball and its preparation method and application 技术领域technical field
本发明属于纳米多孔材料技术领域，具体地讲，涉及一种尺寸可控的气凝胶球及其制备方法和应用。The invention belongs to the technical field of nano-porous materials, and in particular relates to a size-controllable aerogel ball and a preparation method and application thereof.
背景技术Background technique
作为一种新型的多孔材料，气凝胶球由于其大的比表面积、有序的微观结构以及可调控的孔径大小在能源储存、传感器、生物组织工程及环境保护等领域具有广阔的应用前景，在近年来受到了广泛关注。同时，气凝胶球也可作为一种导热填料，气凝胶球本质是气凝胶，相互连通后可形成宏观的三维导热网络，提高复合材料的导热性能。如何有效地调控规整性和尺寸一直是制备气凝胶球的关键技术问题。气凝胶球的微观结构与组装技术和组装单元的形貌有关。虽然在过去的十年中，气凝胶的制备技术快速发展，但仍存在如下几个问题：As a new type of porous material, aerogel spheres have broad application prospects in the fields of energy storage, sensors, biological tissue engineering and environmental protection due to their large specific surface area, ordered microstructure and tunable pore size. has received extensive attention in recent years. At the same time, aerogel spheres can also be used as a thermal conductive filler. Aerogel spheres are essentially aerogels, which can form a macroscopic three-dimensional thermal conduction network after being interconnected to improve the thermal conductivity of composite materials. How to effectively control the regularity and size has always been a key technical issue in the preparation of aerogel spheres. The microstructure of aerogel spheres is related to the assembly technique and the morphology of the assembled unit. Although the preparation technology of aerogel has developed rapidly in the past decade, there are still several problems as follows:
(1)前期的技术大多限制在特定的组装单元或者对组装单元的形貌有限定，比如浙江大学公开的一种湿法制备石墨烯球的方法，这种方法只限于石墨烯、而不能用于其他材料。同样的，日本京都大学了一种只面向二维材料、基于层层自组装的制备气凝胶球的技术，这种技术无法应用于颗粒或者一维的线状材料。(1) Most of the previous technologies are limited to specific assembly units or have restrictions on the morphology of the assembly units. For example, a method for preparing graphene balls by wet method disclosed by Zhejiang University is limited to graphene, and cannot be used for on other materials. Similarly, Kyoto University in Japan has developed a technology for preparing aerogel spheres based on layer-by-layer self-assembly only for two-dimensional materials, which cannot be applied to particles or one-dimensional wire-like materials.
(2)目前，制备多孔球的技术工艺主要包括模板法、液-液相注射、水/溶剂热。上述三种方法都有某种缺点，比如产率低、制备过程复杂等，使其实际应用受限。例如，单分散的二氧化硅或者聚酯微球通常用作制备多孔空心球的模板，然后使目标产物的前驱体覆盖在模板表面，反应完成后再除去前驱体，制备过程较为复杂。(2) At present, the technical processes for preparing porous spheres mainly include template method, liquid-liquid phase injection, and water/solvothermal. The above three methods all have certain disadvantages, such as low yield and complicated preparation process, which limit their practical application. For example, monodispersed silica or polyester microspheres are usually used as templates for preparing porous hollow spheres, and then the precursor of the target product is covered on the surface of the template, and the precursor is removed after the reaction is completed. The preparation process is complicated.
(3)当气凝胶球作为复合材料的填料以及应用在环境保护等领域时，大批量生产就显得尤为重要。然而，目前报道的大部分制备技术只能实现实验室的微量制备，受限于成本、设备等因素无法大批量生产。(3) Mass production is particularly important when aerogel spheres are used as fillers in composite materials and used in environmental protection and other fields. However, most of the preparation technologies reported so far can only achieve micro preparation in the laboratory, and cannot be mass-produced due to factors such as cost and equipment.
因此，发明一种简单、快速和通用的制备尺寸可控的气凝胶球的方法具有十分重要的意义。Therefore, it is of great significance to invent a simple, rapid and general method for preparing size-controllable aerogel spheres.
发明内容SUMMARY OF THE INVENTION
针对上述背景技术中提出的问题，本发明目的在于克服现有技术的上述不足，提供了一种通用的制备尺寸可控的气凝胶球的方法，广泛地适用于零维颗粒、一维管/线状材料以及二维材料，不受限于材料种类和形貌，该方法解决了现有通常方法适用材料范围窄、制备过程复杂以及产率低的技术瓶颈。In view of the problems raised in the above-mentioned background technology, the purpose of the present invention is to overcome the above-mentioned deficiencies of the prior art, and provide a general method for preparing size-controllable aerogel spheres, which is widely applicable to zero-dimensional particles, one-dimensional tubes /Linear materials and two-dimensional materials are not limited by material types and morphology, and the method solves the technical bottleneck of narrow applicable material range, complex preparation process and low yield of existing common methods.
为了达到上述发明目的，本发明的技术方案如下：In order to achieve the above-mentioned purpose of the invention, the technical scheme of the present invention is as follows:
本发明第一个方面提供一种尺寸可控的气凝胶球的制备方法，包括如下步骤：A first aspect of the present invention provides a method for preparing a size-controllable aerogel ball, comprising the following steps:
步骤一、将填料、粘度调节剂、盐与水按照质量比1：(0.05～0.2)：(0.025～0.05)：(5～50)进行混合处理，得到功能化的填料浆料；Step 1: Mix filler, viscosity modifier, salt and water according to the mass ratio of 1:(0.05-0.2):(0.025-0.05):(5-50) to obtain functionalized filler slurry;
步骤二、将所述功能化的填料浆料放入电喷处理装置，通过收集装置收集得到直径可控的填料浆料液滴；Step 2: Put the functionalized filler slurry into the electrospray treatment device, and collect the filler slurry droplets with controllable diameters through the collection device;
步骤三、将所述直径可控的填料浆料液滴滴入低温制冷介质，进行冷冻处理形成冰冻混合物，并将所述冰冻混合物进行冷冻干燥处理，得到气凝胶球前驱体；Step 3, dropping droplets of the filler slurry with a controllable diameter into a low-temperature refrigeration medium, performing freezing treatment to form a frozen mixture, and subjecting the frozen mixture to freeze-drying treatment to obtain aerogel sphere precursors;
步骤四、将所述气凝胶球前驱体进行第一、第二烧结热处理，得到气凝胶球。Step 4: Perform the first and second sintering heat treatments on the aerogel sphere precursor to obtain aerogel spheres.
在本发明的技术方案中，所述填料选用不与水在常温下发生化学反应的任一种物质，选用但不仅限于氧化铝、氧化镁、氧化锌、氮化铝、氮化硼、碳化 硅、石墨烯中的至少一种。只要目标填料不与水发生化学反应且可以在水中分散，就可以基于本发明方法制备成气凝胶球。In the technical scheme of the present invention, the filler is selected from any material that does not chemically react with water at room temperature, but is not limited to aluminum oxide, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide , at least one of graphene. As long as the target filler does not chemically react with water and can be dispersed in water, it can be prepared into aerogel spheres based on the method of the present invention.
优选的，所述填料选用所述填料选用但不仅限于颗粒、线状或者片状的任意一种，或其自由组合。颗粒、线状或者片状的任意一种，或其自由组合都可以基于本发明方法制备成气凝胶球。所述填料的粒径为50nm～100μm。Preferably, the filler is selected from, but not limited to, any one of particles, lines or sheets, or any combination thereof. Any one of particles, threads or sheets, or any combination thereof can be prepared into aerogel spheres based on the method of the present invention. The particle size of the filler is 50 nm˜100 μm.
在本发明的技术方案中，所述粘度控制剂选用羧甲基纤维素钠、羧甲基纤维素、羟丙基甲基纤维素或羟乙基纤维素中的至少一种。选用该些粘度调节剂能有效提高填料在水中的分散性、避免发生填料的团聚现象，并提高气凝胶球前驱体的机械性能，以便于后续的烧结热处理。In the technical solution of the present invention, the viscosity control agent is selected from at least one of sodium carboxymethyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose or hydroxyethyl cellulose. The selection of these viscosity modifiers can effectively improve the dispersibility of the filler in water, avoid the agglomeration of the filler, and improve the mechanical properties of the aerogel sphere precursor to facilitate subsequent sintering heat treatment.
在本发明的技术方案中，所述盐选用氯化钠、硫酸钠、氯化钾、硫酸钾或硝酸钾中的至少一种。盐的加入可以提高填料浆料的导电性，以便于电场力作用在填料浆料液滴上。In the technical scheme of the present invention, the salt is selected from at least one of sodium chloride, sodium sulfate, potassium chloride, potassium sulfate or potassium nitrate. The addition of salt can improve the conductivity of the filler slurry so that the electric field force acts on the filler slurry droplets.
在本发明的技术方案中，所述的混合处理采用的是行星搅拌机搅拌，将填料、粘度调节剂、盐与水按照一定质量比例进行混合处理后，得到短时间均匀的填料分散液。在一实施例中，所述混合处理是采用行星搅拌机处理，且所述行星搅拌机的转速为20～80rpm，时间为0.2～5h。将混合处理采用行星搅拌机处理，并将行星搅拌机处理的转速和时间进行控制，使得填料浆料***稳定，填料均匀分散。In the technical solution of the present invention, the mixing treatment adopts a planetary mixer to stir, and after mixing the filler, viscosity modifier, salt and water according to a certain mass ratio, a uniform filler dispersion liquid in a short time is obtained. In one embodiment, the mixing treatment is performed by a planetary mixer, and the rotation speed of the planetary mixer is 20-80 rpm, and the time is 0.2-5 h. The mixing process is processed by a planetary mixer, and the speed and time of the planetary mixer are controlled, so that the filler slurry system is stable and the filler is uniformly dispersed.
在本发明的技术方案中，所述电喷处理装置主要作用为在填料浆料喷射端与收集装置之间引入电场，填料浆料喷射端与收集装置之间的距离为10～50cm，填料浆料喷射端与收集装置之间的电压差为2～25kV，浆料液滴的直径为9μm～2.7mm。In the technical solution of the present invention, the electrospray treatment device is mainly used to introduce an electric field between the injection end of the filler slurry and the collection device, the distance between the injection end of the filler slurry and the collection device is 10-50 cm, and the filler slurry The voltage difference between the material ejection end and the collecting device is 2-25kV, and the diameter of the slurry droplet is 9μm-2.7mm.
在本发明的技术方案中，所述电喷处理装置配备有自动推进装置，推进速率为0.1～10cm/min。推进速率可以控制气凝胶球的产率和形貌良率。In the technical solution of the present invention, the EFI treatment device is equipped with an automatic propulsion device, and the propulsion rate is 0.1-10 cm/min. The propulsion rate can control the yield and morphology yield of the aerogel spheres.
所述低温制冷介质为液氮或液氦中的至少一种；The cryogenic refrigeration medium is at least one of liquid nitrogen or liquid helium;
在本发明的技术方案中，所述冷冻处理为将填料浆料液滴滴落在低温制冷介质表面，从而引发连续的自组装成型过程，冷冻时间为2～30s，是为了使得浆料液滴中的水结冰并对填料形成放射状的取向。In the technical solution of the present invention, the freezing treatment is to drop the filler slurry droplets on the surface of the low-temperature refrigeration medium, thereby triggering a continuous self-assembly molding process, and the freezing time is 2-30s, in order to make the slurry droplets droplets The water in it freezes and orients the filler radially.
在本发明的技术方案中，所述冷冻干燥处理的真空度为-15Pa～-50Pa，冷冻温度为-45℃～20℃，冷冻时间为2h～6h。In the technical solution of the present invention, the vacuum degree of the freeze-drying treatment is -15Pa～-50Pa, the freezing temperature is -45°C～20°C, and the freezing time is 2h～6h.
在本发明的技术方案中，所述第一烧结温度为350℃～400℃，烧结时间为4h～6h；所述第二烧结温度为800℃～1800℃，烧结时间为6h～12h。In the technical solution of the present invention, the first sintering temperature is 350°C-400°C, and the sintering time is 4h-6h; the second sintering temperature is 800°C-1800°C, and the sintering time is 6h-12h.
本发明第二个方面提供一种气凝胶球，所述气凝胶球是由本发明所述的制备方法制备得到，且所述气凝胶球的比表面积为50m 2/g～250m 2/g，所述气凝胶球的密度为20mg/cm 3～200mg/cm 3，所述气凝胶球的孔隙率为74％～96％，所述气凝胶球的直径为10μm～3.0mm。 The second aspect of the present invention provides an aerogel ball, the aerogel ball is prepared by the preparation method of the present invention, and the specific surface area of the aerogel ball is 50m 2 /g～250m 2 / g, the density of the aerogel balls is 20 mg/cm 3 to 200 mg/cm 3 , the porosity of the aerogel balls is 74% to 96%, and the diameter of the aerogel balls is 10 μm to 3.0 mm .
本发明第三个方面提供由本发明通用的制备尺寸可控的气凝胶球的方法制备的气凝胶球在环境保护、能源储存、复合材料、军事及航天领域中的应用。The third aspect of the present invention provides the application of the aerogel balls prepared by the general method of the present invention for preparing size-controllable aerogel balls in the fields of environmental protection, energy storage, composite materials, military and aerospace.
与现有技术相比，本发明具有以下有益效果：Compared with the prior art, the present invention has the following beneficial effects:
1、本发明通用的制备尺寸可控的气凝胶球的方法将填料、粘度调节剂、盐与水混合形成功能化的填料浆料，并通过电喷控制装置控制填料浆料液滴的直径，只需将浆料液滴经冷冻处理、冷冻干燥和烧结热处理即可，使得本方法适用材料范围广、气凝胶尺寸可控、制备过程简单、反应条件相对温和以及产率高，有效解决了现有通常方法适用材料范围窄、制备过程复杂以及产率低的技术瓶颈，并拓宽了气凝胶球在各领域的应用前景。1. The general method of the present invention for preparing size-controllable aerogel spheres mixes fillers, viscosity modifiers, salts and water to form functionalized filler slurry, and controls the diameter of the filler slurry droplets through an electrospray control device , the slurry droplets only need to undergo freezing treatment, freeze drying and sintering heat treatment, so that the method has a wide range of applicable materials, controllable aerogel size, simple preparation process, relatively mild reaction conditions and high yield. The technical bottleneck of the existing conventional methods such as narrow applicable material range, complicated preparation process and low yield is solved, and the application prospect of the aerogel spheres in various fields is broadened.
2、本发明方法通过工艺步骤和条件的控制，制备得到的气凝胶球比表面积大、密度低、孔隙率高、具有分级的三维结构，呈现独特的放射状、类似海胆的微观形貌，并且气凝胶球的直径可精确控制，在实施例1中，制备得到的气凝胶球的比表面积为200m 2/g，所述气凝胶球的密度为150mg/cm 3，所述气凝胶球的孔隙率为88％，所述气凝胶球的直径为200μm。因此，本发明实施 例气凝胶球比表面积大、密度低、孔隙率高、尺寸可精确控制。 2. Through the control of process steps and conditions, the prepared aerogel spheres have a large specific surface area, low density, high porosity, a hierarchical three-dimensional structure, a unique radial shape, and a microscopic morphology similar to sea urchins. The diameter of the aerogel spheres can be precisely controlled. In Example 1, the specific surface area of the prepared aerogel spheres is 200 m 2 /g, the density of the aerogel spheres is 150 mg/cm 3 , and the The porosity of the gel spheres was 88%, and the diameter of the aerogel spheres was 200 μm. Therefore, the aerogel spheres of the embodiments of the present invention have large specific surface area, low density, high porosity, and the size can be precisely controlled.
3、本发明方法制备的气凝胶球具有优异的综合结构特性和可调控性，因此，其可以更加广泛地应用于环境保护、能源储存、复合材料、军事及航天领域等领域。3. The aerogel balls prepared by the method of the present invention have excellent comprehensive structural properties and controllability, so they can be more widely used in the fields of environmental protection, energy storage, composite materials, military and aerospace fields.
附图说明Description of drawings
图1为本发明实施例通用的制备尺寸可控的气凝胶球的方法的制备方法流程图；FIG. 1 is a flow chart of a preparation method of a method for preparing size-controllable aerogel spheres commonly used in an embodiment of the present invention;
图2为本发明实施例通用的制备尺寸可控的气凝胶球的方法的电喷控制设备说明图；2 is an explanatory diagram of an electrospray control device for a method for preparing size-controllable aerogel balls commonly used in an embodiment of the present invention;
图3为实施例1制备的氮化硼微米片气凝胶球的成型过程说明图；3 is an explanatory diagram of the molding process of the boron nitride micro-sheet aerogel ball prepared in Example 1;
图4为实施例1制备的氮化硼微米片气凝胶球的扫描电镜(SEM)图；Fig. 4 is the scanning electron microscope (SEM) image of the boron nitride microplate aerogel sphere prepared in Example 1;
图5为实施例2制备的碳化硅纳米线气凝胶球的扫描电镜(SEM)图。FIG. 5 is a scanning electron microscope (SEM) image of the silicon carbide nanowire aerogel spheres prepared in Example 2. FIG.
具体实施方式Detailed ways
下面结合实施例以及对比例，对本发明作进一步地详细说明，但本发明的实施方式不限于此。具体包括以下实施例：The present invention will be further described in detail below with reference to the examples and comparative examples, but the embodiments of the present invention are not limited thereto. Specifically include the following embodiments:
为了使本发明要解决的技术问题、技术方案及有益效果更加清楚明白，以下结合实施例与附图，对本发明进行进一步详细说明。应当理解，此处所描述的具体实施例仅用以解释本发明，并不用于限定本发明。In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.
本发明提供了一种通用的制备尺寸可控的气凝胶球的方法。本发明通用的制备尺寸可控的气凝胶球的方法工艺步骤如图1所示，其包括如下步骤：The present invention provides a general method for preparing size-controllable aerogel spheres. The general process steps of the method for preparing size-controllable aerogel balls of the present invention are shown in Figure 1, which includes the following steps:
S01.制备功能化的填料浆料：将填料、粘度调节剂、盐与水按照质量比1：(0.05～0.2)：(0.025～0.05)：(5～50)进行混合处理，得到功能化的填 料浆料；S01. Preparation of functionalized filler slurry: Mix filler, viscosity modifier, salt and water in a mass ratio of 1:(0.05-0.2):(0.025-0.05):(5-50) to obtain functionalized filler filler slurry;
S02.对功能化的填料浆料进行电喷处理：将所述功能化的填料浆料放入电喷处理装置，得到直径可控的填料浆料液滴；S02. Perform electrospray treatment on the functionalized filler slurry: put the functionalized filler slurry into an electrospray treatment device to obtain filler slurry droplets with a controllable diameter;
S03.对电喷出来的功能化的填料浆料液滴制备气凝胶球前驱体：将所述直径可控的填料浆料液滴滴入低温制冷介质，进行冷冻处理形成冰冻混合物，并将所述冰冻混合物进行冷冻干燥处理，得到气凝胶球前驱体；S03. Prepare aerogel sphere precursors from electrosprayed functionalized filler slurry droplets: drop the diameter-controllable filler slurry droplets into a low-temperature refrigeration medium, perform freezing treatment to form a frozen mixture, and mix The frozen mixture is freeze-dried to obtain aerogel sphere precursors;
S04.对气凝胶前驱体进行烧结热处理：将所述气凝胶球前驱体进行第一、第二烧结热处理，得到气凝胶球。S04. Perform sintering heat treatment on the aerogel precursor: perform the first and second sintering heat treatments on the aerogel sphere precursor to obtain aerogel spheres.
本发明所采用的的电喷处理装置主要作用为在填料浆料喷射端与收集装置之间引入电场，填料浆料喷射端与收集装置之间的距离为10～50cm，填料浆料喷射端与收集装置之间的电压差为2～25kV，浆料液滴的直径为9μm～2.7mm。具体地，图2为本发明通用的制备尺寸可控的气凝胶球的方法的电喷控制设备说明图，主要包括超声波发生器、注射器、移动平台、玻璃罩、收集仓和分隔拦板。其中，注射器放置于移动平台上，注射器两侧配有超声波发生器。注射器的注射段连接电极，液滴滴出后经玻璃罩落入下方的收集仓，经由分割挡板筛选后储存。具体地，注射器注射端接高压，收集仓接地，因此在注射端和收集仓之间存在一定强度的电场。功能化的填料浆料在电场中会受到电场力的作用，当电场力和重力的总和大于填料浆料液滴的表面张力及粘附力的总和，填料浆料液滴会滴落。具体地，可以通过改变注射段和收集仓之间的距离以及电压差来改变注射段和收集仓之间的电场强度，从而控制填料浆料液滴受到的电场力，调控填料浆料液滴的最终直径。The main function of the electrospray treatment device used in the present invention is to introduce an electric field between the injection end of the filler slurry and the collection device. The voltage difference between the collecting devices was 2-25 kV, and the diameter of the slurry droplets was 9 μm-2.7 mm. Specifically, FIG. 2 is an explanatory diagram of the electrospray control equipment of the method for preparing size-controllable aerogel balls in general according to the present invention, which mainly includes an ultrasonic generator, a syringe, a mobile platform, a glass cover, a collection bin and a separation baffle. Among them, the syringe is placed on the mobile platform, and the two sides of the syringe are equipped with ultrasonic generators. The injection section of the syringe is connected to the electrode. After the droplets are dropped, they fall into the collection bin below through the glass cover, and are screened by the dividing baffle and stored. Specifically, the injection end of the syringe is connected to a high voltage, and the collection chamber is grounded, so there is an electric field of a certain strength between the injection end and the collection chamber. The functionalized filler slurry will be affected by the electric field force in the electric field. When the sum of the electric field force and the gravity is greater than the sum of the surface tension and the adhesion force of the filler slurry droplet, the filler slurry droplet will drip. Specifically, the electric field strength between the injection section and the collection chamber can be changed by changing the distance and the voltage difference between the injection section and the collection chamber, so as to control the electric field force on the filler slurry droplets and regulate the flow rate of the filler slurry droplets. Final diameter.
具体地，以实施例1制备的氮化硼微米片气凝胶球的成型过程为例说明本发明的制备原理，如图3所示，主要包括四个步骤：Specifically, taking the molding process of the boron nitride micro-sheet aerogel ball prepared in Example 1 as an example to illustrate the preparation principle of the present invention, as shown in Figure 3, it mainly includes four steps:
(1)首先将包含氮化硼微米片的水系浆料逐滴滴入液氮中(图3a)。当液滴落下、刚与液氮表面接触时(图3b)，由于两者之间存在的巨大温差， 液氮会剧烈挥发。挥发的液氮为液滴提供了持续的向上的托力，使液滴浮在液氮表面并保持球形的形状。同时，如图3c所示，局部的冷冻铸造自组装过程立即发生。冰晶会从浆料的一侧、顺着温度梯度进行生长。随着冰晶体积变大，浆料中的氮化硼微米片被排斥、团聚在相邻的冰晶之间(图3d)。冰冻会促进在温度梯度方向上取向骨架的形成，赋予材料各向异性的性质。(1) First, drop the aqueous slurry containing boron nitride microflakes into liquid nitrogen drop by drop (Fig. 3a). When the droplet falls and just comes into contact with the surface of the liquid nitrogen (Fig. 3b), the liquid nitrogen will volatilize violently due to the huge temperature difference between the two. The volatilized liquid nitrogen provides a continuous upward supporting force for the droplet, making the droplet float on the surface of the liquid nitrogen and maintain a spherical shape. Meanwhile, as shown in Fig. 3c, the localized freeze-casting self-assembly process occurs immediately. Ice crystals will grow from one side of the slurry, following the temperature gradient. As the ice crystals became larger, the boron nitride microflakes in the slurry were repelled and agglomerated between adjacent ice crystals (Fig. 3d). Freezing promotes the formation of oriented skeletons in the direction of the temperature gradient, giving the material anisotropic properties.
(2)当局部冰模板法自组装完成后，冰冻的部分由于体积增大而密度减小。因此，未冰冻的部分液滴具有更大的密度，在液氮的驱动下进行旋转、与液氮接触，并重复上述的冷冻铸造自组装过程(图3e)。每次旋转都会在液滴内部形成一层“年轮”，随着旋转的不断进行，冷冻逐渐从液滴表面向液滴内部发展，促进了从核心向外放射状形貌的形成。旋转逐渐减小了液滴与液氮之间的温差，同时旋转也保证了冰冻后液滴的球形形状。(2) When the self-assembly of the local ice template method is completed, the density of the frozen part decreases due to the increase in volume. As a result, the unfrozen part of the droplet with greater density was rotated under the driving force of liquid nitrogen, contacted with liquid nitrogen, and repeated the freeze-casting self-assembly process described above (Fig. 3e). Each rotation will form a layer of "annual rings" inside the droplet. With the continuous rotation, freezing gradually develops from the droplet surface to the inside of the droplet, promoting the formation of radial topography from the core outwards. The rotation gradually reduces the temperature difference between the droplet and the liquid nitrogen, while the rotation also ensures the spherical shape of the droplet after freezing.
(3)随着冷冻铸造自组装过程和液氮驱动的旋转不断进行，液滴内部冰冻区域和半径不断增大，直到液滴内部所有的水都变成了冰。当液滴完全冰冻后，液滴会停止旋转，并沉入到液氮底部(图3f)。最终得到具有海胆状的气凝胶球前驱体(图3g)。(3) As the freeze-casting self-assembly process and liquid nitrogen-driven rotation continue, the frozen area and radius inside the droplet continue to increase until all the water inside the droplet becomes ice. When the droplet is completely frozen, the droplet stops spinning and sinks to the bottom of the liquid nitrogen (Fig. 3f). Finally, the aerogel sphere precursor with sea urchin shape was obtained (Fig. 3g).
在上文所述的通用的制备尺寸可控的气凝胶球的方法的基础上，本发明以下实施例还提供了几种气凝胶球材料。理所当然的是，这几种气凝胶球材料是采用上文通用的制备尺寸可控的气凝胶球的方法制备获得。具体包括以下实施例：On the basis of the general method for preparing size-controllable aerogel spheres described above, the following embodiments of the present invention further provide several aerogel sphere materials. Of course, these several aerogel ball materials are prepared by using the above general method for preparing aerogel balls with controllable size. Specifically include the following embodiments:
实施例1Example 1
实施例1提供的氮化硼微米片气凝胶球的制备方法参照附图1所示，包括如下具体步骤：Referring to Figure 1, the preparation method of the boron nitride microchip aerogel ball provided in Example 1 includes the following specific steps:
S11：将尺寸为500nm的氮化硼微米片、羧甲基纤维素钠、氯化钠与水按照质量比1：0.2：0.05：10混合后在行星搅拌机中搅拌4h，搅拌转速为70rpm，得到功能化的氮化硼微米片浆料；S11: Mix boron nitride micro-flakes with a size of 500 nm, sodium carboxymethyl cellulose, sodium chloride and water according to a mass ratio of 1:0.2:0.05:10, and then stir in a planetary mixer for 4 hours at a stirring speed of 70 rpm to obtain Functionalized boron nitride microchip paste;
S12：将功能化的氮化硼微米片浆料放入电喷处理装置，氮化硼微米片浆料喷射端与收集装置之间的距离为20cm，填料浆料喷射端与收集装置之间的电压差为20kV，自动推进装置的推进速率为1cm/min，氮化硼微米片浆料液滴的直径为180μm；S12: Put the functionalized boron nitride microchip slurry into the electrospray treatment device. The voltage difference is 20kV, the propulsion rate of the automatic propulsion device is 1cm/min, and the diameter of the boron nitride microflake slurry droplet is 180μm;
S13：将所述氮化硼微米片浆料液滴滴入液氮，冷冻时间为6s，取出冰冻混合物进行冷冻干燥处理，冷冻干燥处理的真空度为-45Pa，冷冻温度为-20℃，冷冻时间为4h，得到氮化硼微米片气凝胶球前驱体；S13: drop the boron nitride microchip slurry dropwise into liquid nitrogen, the freezing time is 6s, take out the frozen mixture for freeze-drying treatment, the vacuum degree of freeze-drying treatment is -45Pa, the freezing temperature is -20°C, and the freezing temperature is -20°C. The time is 4h to obtain the boron nitride microchip aerogel sphere precursor;
S14：将氮化硼微米片气凝胶球前驱体进行烧结热处理过程，第一烧结热处理温度为400℃，烧结时间为4h；第二烧结温度为900℃，烧结时间为10h。S14: subject the boron nitride microchip aerogel sphere precursor to a sintering heat treatment process, the first sintering heat treatment temperature is 400°C, and the sintering time is 4h; the second sintering temperature is 900°C, and the sintering time is 10h.
将本发明实施例1制备的氮化硼微米片气凝胶球进行宏观和微观分析，其微观结构通过SEM扫描如图4所示，从图4中可以观察到明显的多孔结构，平均孔径在10～40μm，同时可以看到氮化硼微米片互相连接、形成多孔结构。得到的氮化硼微米片气凝胶球的比表面积为200m 2/g，气凝胶球的密度为150mg/cm 3，气凝胶球的孔隙率为88％，气凝胶球的直径为200μm。 The boron nitride microflake aerogel spheres prepared in Example 1 of the present invention were analyzed macroscopically and microscopically. 10-40 μm, and it can be seen that the boron nitride microplates are connected to each other to form a porous structure. The specific surface area of the obtained boron nitride microplate aerogel spheres is 200 m 2 /g, the density of the aerogel spheres is 150 mg/cm 3 , the porosity of the aerogel spheres is 88%, and the diameter of the aerogel spheres is 200μm.
实施例2Example 2
实施例2提供的碳化硅纳米线气凝胶球的制备方法参照附图1所示，包括如下具体步骤：The preparation method of the silicon carbide nanowire aerogel ball provided in Example 2 is shown in FIG. 1, including the following specific steps:
S21：将直径为200nm、长度为10μm的碳化硅纳米线、羟丙基甲基纤维素、氯化钾与水按照质量比1：0.05：0.05：20混合后在行星搅拌机中搅拌3h，搅拌转速为60rpm，得到功能化的碳化硅纳米线浆料；S21: Mix silicon carbide nanowires with a diameter of 200 nm and a length of 10 μm, hydroxypropyl methylcellulose, potassium chloride and water according to a mass ratio of 1:0.05:0.05:20, and then stir in a planetary mixer for 3 hours, and the stirring speed is 60 rpm to obtain functionalized silicon carbide nanowire slurry;
S22：将功能化的碳化硅纳米线浆料放入电喷处理装置，碳化硅纳米线浆料喷射端与收集装置之间的距离为10cm，填料浆料喷射端与收集装置之间的电压差为22kV，自动推进装置的推进速率为3cm/min，碳化硅纳米线浆料液滴的直径为100μm；S22: Put the functionalized silicon carbide nanowire slurry into the electrospray treatment device, the distance between the spraying end of the silicon carbide nanowire slurry and the collecting device is 10 cm, and the voltage difference between the spraying end of the filler slurry and the collecting device is 22kV, the propulsion rate of the automatic propulsion device is 3cm/min, and the diameter of the silicon carbide nanowire slurry droplet is 100μm;
S23：将所述碳化硅纳米线浆料液滴滴入液氦，冷冻时间为5s，取出冰冻混合物进行冷冻干燥处理，冷冻干燥处理的真空度为-50Pa，冷冻温度为-45℃，冷冻时间为3h，得到碳化硅纳米线气凝胶球前驱体；S23: drop the silicon carbide nanowire slurry dropwise into liquid helium, the freezing time is 5s, take out the frozen mixture for freeze-drying treatment, the vacuum degree of the freeze-drying treatment is -50Pa, the freezing temperature is -45°C, and the freezing time is For 3h, the precursor of silicon carbide nanowire aerogel spheres was obtained;
S24：将碳化硅纳米线气凝胶球前驱体进行烧结热处理过程，第一烧结热处理温度为390℃，烧结时间为5h；第二烧结温度为1000℃，烧结时间为4h。S24: The silicon carbide nanowire aerogel sphere precursor is subjected to a sintering heat treatment process, the first sintering heat treatment temperature is 390°C, and the sintering time is 5h; the second sintering temperature is 1000°C, and the sintering time is 4h.
将本发明实施例2制备的纳米线气凝胶球进行宏观和微观分析，其微观结构图通过SEM扫描如图5所示，从图5中可以看出，取向、薄以及多孔的碳化硅纳米线“墙”组成的高度互连、分级的微观结构。碳化硅纳米线气凝胶球表面具有宏观尺寸的孔。上述碳化硅纳米线气凝胶球的比表面积为220m 2/g，所述气凝胶球的密度为70mg/cm 3，所述气凝胶球的孔隙率为95％，所述气凝胶球的直径为115μm。 The nanowire aerogel spheres prepared in Example 2 of the present invention were analyzed macroscopically and microscopically. A highly interconnected, hierarchical microstructure of wire "walls". The surface of silicon carbide nanowire aerogel spheres has macroscopic-sized pores. The specific surface area of the above-mentioned silicon carbide nanowire aerogel ball is 220 m 2 /g, the density of the aerogel ball is 70 mg/cm 3 , the porosity of the aerogel ball is 95%, and the aerogel ball has a porosity of 95%. The diameter of the ball is 115 μm.
实施例3Example 3
实施例3提供的氧化铝颗粒气凝胶球的制备方法参照附图1所示，包括如下具体步骤：Referring to Figure 1, the preparation method of the alumina particle aerogel ball provided in Example 3 includes the following specific steps:
S31：将尺寸为40μm的氧化铝颗粒、羟乙基纤维素、硫酸钠与水按照质量比1：0.15：0.03：5混合后在行星搅拌机中搅拌2h，搅拌转速为50rpm，得到功能化的氧化铝颗粒浆料；S31: Alumina particles with a size of 40 μm, hydroxyethyl cellulose, sodium sulfate and water are mixed in a mass ratio of 1:0.15:0.03:5, and then stirred in a planetary mixer for 2 hours at a stirring speed of 50 rpm to obtain functionalized oxidized Aluminum particle slurry;
S32：将功能化的氧化铝颗粒浆料放入电喷处理装置，氧化铝颗粒浆料喷射端与收集装置之间的距离为50cm，填料浆料喷射端与收集装置之间的电压差为5kV，自动推进装置的推进速率为7cm/min，氧化铝颗粒浆料液滴的直径为2.2mm；S32: Put the functionalized alumina particle slurry into the electrospray treatment device, the distance between the spray end of the alumina particle slurry and the collecting device is 50cm, and the voltage difference between the spray end of the filler slurry and the collecting device is 5kV , the propulsion rate of the automatic propulsion device is 7cm/min, and the diameter of the alumina particle slurry droplet is 2.2mm;
S33：将所述氧化铝颗粒浆料液滴滴入液氮，冷冻时间为28s，取出冰冻混合物进行冷冻干燥处理，冷冻干燥处理的真空度为-10Pa，冷冻温度为-15℃，冷冻时间为6h，得到氧化铝颗粒气凝胶球前驱体；S33: drop the alumina particle slurry into liquid nitrogen, the freezing time is 28s, take out the frozen mixture for freeze-drying treatment, the vacuum degree of the freeze-drying treatment is -10Pa, the freezing temperature is -15°C, and the freezing time is 6h, the alumina particle aerogel sphere precursor was obtained;
S34：将氧化铝颗粒气凝胶球前驱体进行烧结热处理过程，第一烧结热处理温度为350℃，烧结时间为2h；第二烧结温度为1200℃，烧结时间为5h。S34: the alumina particle aerogel ball precursor is subjected to a sintering heat treatment process, the first sintering heat treatment temperature is 350°C, and the sintering time is 2h; the second sintering temperature is 1200°C, and the sintering time is 5h.
将本发明实施例3制备的氧化铝颗粒气凝胶球进行宏观和微观分析。上述氧化铝颗粒气凝胶球的比表面积为70m 2/g，所述气凝胶球的密度为310mg/cm 3，所述气凝胶球的孔隙率为77％，所述气凝胶球的直径为2.45mm。 The alumina particle aerogel spheres prepared in Example 3 of the present invention were subjected to macroscopic and microscopic analysis. The specific surface area of the above alumina particle aerogel spheres is 70m 2 /g, the density of the aerogel spheres is 310mg/cm 3 , the porosity of the aerogel spheres is 77%, the aerogel spheres The diameter is 2.45mm.
实施例4Example 4
实施例4提供的氧化锌颗粒气凝胶球的制备方法参照附图1所示，包括如下具体步骤：The preparation method of the zinc oxide particle aerogel ball provided in Example 4 is shown in Figure 1, and includes the following specific steps:
S41：将尺寸为80μm的氧化锌颗粒、羟乙基纤维素、硫酸钠与水按照质量比1：0.2：0.02：6混合后在行星搅拌机中搅拌2h，搅拌转速为40rpm，得到功能化的氧化锌颗粒浆料；S41: Mix zinc oxide particles with a size of 80 μm, hydroxyethyl cellulose, sodium sulfate and water in a mass ratio of 1:0.2:0.02:6, and then stir in a planetary mixer for 2 hours, and the stirring speed is 40 rpm to obtain functionalized oxidized Zinc particle slurry;
S42：将功能化的氧化锌颗粒浆料放入电喷处理装置，氧化锌颗粒浆料喷射端与收集装置之间的距离为50cm，填料浆料喷射端与收集装置之间的电压差为3kV，自动推进装置的推进速率为3cm/min，氧化锌颗粒浆料液滴的直径为2.4mm；S42: Put the functionalized zinc oxide particle slurry into the electrospray treatment device, the distance between the spraying end of the zinc oxide particle slurry and the collecting device is 50cm, and the voltage difference between the spraying end of the filler slurry and the collecting device is 3kV , the propulsion rate of the automatic propulsion device is 3cm/min, and the diameter of the zinc oxide particle slurry droplet is 2.4mm;
S43：将所述氧化锌颗粒浆料液滴滴入液氮，冷冻时间为30s，取出冰冻混合物进行冷冻干燥处理，冷冻干燥处理的真空度为-20Pa，冷冻温度为-15℃，冷冻时间为5h，得到氧化锌颗粒气凝胶球前驱体；S43: drop the zinc oxide particle slurry into liquid nitrogen, the freezing time is 30s, and the frozen mixture is taken out and subjected to freeze-drying treatment. The vacuum degree of the freeze-drying treatment is -20Pa, the freezing temperature is -15°C, and the freezing time is 5h, the zinc oxide particle aerogel sphere precursor was obtained;
S44：将氧化锌颗粒气凝胶球前驱体进行烧结热处理过程，第一烧结热处理温度为350℃，烧结时间为3h；第二烧结温度为800℃，烧结时间为6h。S44: the zinc oxide particle aerogel ball precursor is subjected to a sintering heat treatment process, the first sintering heat treatment temperature is 350°C, and the sintering time is 3h; the second sintering temperature is 800°C, and the sintering time is 6h.
将本发明实施例4制备的氧化锌颗粒气凝胶球进行宏观和微观分析。上述氧化锌颗粒气凝胶球的比表面积为53m 2/g，所述气凝胶球的密度为350mg/cm 3，所述气凝胶球的孔隙率为74％，所述气凝胶球的直径为2.67mm。 The zinc oxide particle aerogel spheres prepared in Example 4 of the present invention were subjected to macroscopic and microscopic analysis. The specific surface area of the above-mentioned zinc oxide particle aerogel balls is 53 m 2 /g, the density of the aerogel balls is 350 mg/cm 3 , the porosity of the aerogel balls is 74%, and the aerogel balls The diameter is 2.67mm.
上述实施例为本发明较佳的实施方式，但本发明的实施方式并不受所述实施例的限制，其他的任何未背离本发明的精神实质与原理下所作的改变、修饰、 替代、组合、简化，均应为等效的置换方式，都包含在本发明的保护范围之内。The above-mentioned embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the described embodiments, and any other changes, modifications, substitutions, and combinations that do not deviate from the spirit and principle of the present invention are made. , simplification, all should be equivalent replacement modes, and are all included in the protection scope of the present invention.
显然，本领域的技术人员可以对本发明进行各种改动和变型而不脱离本发明的精神和范围。这样，倘若本发明的这些修改和变型属于本发明权利要求及其等同技术的范围之内，则本发明也意图包含这些改动和变型在内。It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (10)

  1. 一种尺寸可控的气凝胶球的制备方法，其特征在于，包括如下步骤：A method for preparing a size-controllable aerogel ball, characterized in that it comprises the following steps:
    步骤一、将填料、粘度调节剂、盐与水按照质量比1：(0.05～0.2)：(0.025～0.05)：(5～50)进行混合处理，得到功能化的填料浆料；Step 1: Mix filler, viscosity modifier, salt and water according to the mass ratio of 1:(0.05-0.2):(0.025-0.05):(5-50) to obtain functionalized filler slurry;
    步骤二、将所述功能化的填料浆料放入电喷处理装置，通过收集装置收集得到直径可控的填料浆料液滴；Step 2: Put the functionalized filler slurry into the electrospray treatment device, and collect the filler slurry droplets with controllable diameters through the collection device;
    步骤三、将所述直径可控的填料浆料液滴滴入低温制冷介质，进行冷冻处理形成冰冻混合物，并将所述冰冻混合物进行冷冻干燥处理，得到气凝胶球前驱体；Step 3, dropping droplets of the filler slurry with a controllable diameter into a low-temperature refrigeration medium, performing freezing treatment to form a frozen mixture, and subjecting the frozen mixture to freeze-drying treatment to obtain aerogel sphere precursors;
    步骤四、将所述气凝胶球前驱体进行第一、第二烧结热处理，得到气凝胶球。Step 4: Perform the first and second sintering heat treatments on the aerogel sphere precursor to obtain aerogel spheres.
  2. 根据权利要求1所述的尺寸可控的气凝胶球的制备方法，其特征在于：所述填料为不与水在常温下发生化学反应的任一种物质，优选的，所述填料包括氧化铝、氧化镁、氧化锌、氮化铝、氮化硼、碳化硅、石墨烯；The method for preparing size-controllable aerogel balls according to claim 1, wherein the filler is any substance that does not chemically react with water at room temperature, and preferably, the filler includes an oxidized material. Aluminum, magnesium oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide, graphene;
    优选的，所述填料的外观形貌为颗粒、线状或者片状的任意一种或多种；所述填料的粒径为50nm～100μm。Preferably, the appearance of the filler is any one or more of particles, lines or flakes; the particle size of the filler is 50 nm to 100 μm.
  3. 根据权利要求1所述的尺寸可控的气凝胶球的制备方法，其特征在于：所述粘度调节剂为羧甲基纤维素钠、羧甲基纤维素、羟丙基甲基纤维素或羟乙基纤维素中的至少一种。The method for preparing size-controllable aerogel balls according to claim 1, wherein the viscosity modifier is sodium carboxymethyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose or At least one of hydroxyethyl cellulose.
  4. 根据权利要求1所述的尺寸可控的气凝胶球的制备方法，其特征在于：所述盐为氯化钠、硫酸钠、氯化钾、硫酸钾或硝酸钾中的至少一种。The method for preparing size-controllable aerogel balls according to claim 1, wherein the salt is at least one of sodium chloride, sodium sulfate, potassium chloride, potassium sulfate or potassium nitrate.
  5. 根据权利要求1所述的尺寸可控的气凝胶球的制备方法，其特征在于：所述的混合处理采用的是行星搅拌机搅拌，行星搅拌机的转速为20～80rpm，时间为0.2～5h。The method for preparing size-controllable aerogel balls according to claim 1, characterized in that: the mixing treatment adopts a planetary mixer to stir, and the rotation speed of the planetary mixer is 20-80 rpm, and the time is 0.2-5 h.
  6. 根据权利要求1所述的尺寸可控的气凝胶球的制备方法，其特征在于：所述填料浆料喷射端与收集装置之间的距离为10～50cm，填料浆料喷射端与收集装置之间的电压差为2～25kV，浆料液滴的直径为9μm～2.7mm；The method for preparing size-controllable aerogel balls according to claim 1, characterized in that: the distance between the jetting end of the filler slurry and the collecting device is 10-50 cm, and the jetting end of the filler slurry and the collecting device are at a distance of 10-50 cm The voltage difference between them is 2～25kV, and the diameter of the slurry droplets is 9μm～2.7mm;
    优选的，所述电喷处理装置配备有自动推进装置，推进速率为0.1～10cm/min。Preferably, the electrospray treatment device is equipped with an automatic propulsion device, and the propulsion rate is 0.1-10 cm/min.
  7. 根据权利要求1所述的尺寸可控的气凝胶球的制备方法，其特征在于：所述低温制冷介质为液氮或液氦中的至少一种；The method for preparing size-controllable aerogel balls according to claim 1, wherein the low-temperature refrigeration medium is at least one of liquid nitrogen or liquid helium;
    优选的，所述冷冻处理为将填料浆料液滴滴落在低温制冷介质表面，从而引发连续的自组装成型过程，冷冻时间为2～30s；Preferably, the freezing treatment is to drop the filler slurry droplets on the surface of the low-temperature refrigeration medium, thereby triggering a continuous self-assembly molding process, and the freezing time is 2-30s;
    优选的，所述冷冻干燥处理的真空度为-15Pa～-50Pa，冷冻温度为-45℃～20℃，冷冻时间为2h～6h。Preferably, the vacuum degree of the freeze-drying treatment is -15Pa～-50Pa, the freezing temperature is -45°C～20°C, and the freezing time is 2h～6h.
  8. 根据权利要求1所述的尺寸可控的气凝胶球的制备方法，其特征在于：所述第一烧结温度为350℃～400℃，烧结时间为4h～6h；所述第二烧结温度为800℃～1800℃，烧结时间为6h～12h。The method for preparing size-controllable aerogel balls according to claim 1, wherein the first sintering temperature is 350°C to 400°C, and the sintering time is 4h to 6h; the second sintering temperature is 800℃～1800℃, the sintering time is 6h～12h.
  9. 一种气凝胶球，其特征在于：所述气凝胶球是由权利要求1-8任意一项所述的制备方法制备得到，所述气凝胶球的比表面积为50m 2/g～250m 2/g，所述气凝胶球的密度为20mg/cm 3～200mg/cm 3，所述气凝胶球的孔隙率为74％～96％，所述气凝胶球的直径为10μm～3.0mm。 An aerogel ball, characterized in that: the aerogel ball is prepared by the preparation method according to any one of claims 1-8, and the specific surface area of the aerogel ball is 50 m 2 /g～ 250m 2 /g, the density of the aerogel balls is 20mg/cm 3 to 200mg/cm 3 , the porosity of the aerogel balls is 74% to 96%, and the diameter of the aerogel balls is 10 μm ~3.0mm.
  10. 如权利要求9所述的气凝胶球在环境保护、能源储存、复合材料、军事及航天领域中的应用。Application of the aerogel ball according to claim 9 in the fields of environmental protection, energy storage, composite materials, military and aerospace.
PCT/CN2020/135250 2020-12-10 2020-12-10 Size-controllable aerogel ball and preparation method and application thereof WO2022120712A1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115159535A (en) * 2022-07-29 2022-10-11 武汉科技大学 Magnesium aluminate spinel aerogel and preparation method thereof
CN115505255A (en) * 2022-09-22 2022-12-23 浙江大学 Boron nitride polymer composite material and preparation method and application thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102898174A (en) * 2011-07-29 2013-01-30 深圳光启创新技术有限公司 Porous ceramic microsphere material and preparation method thereof
CN103204695A (en) * 2013-03-11 2013-07-17 西安理工大学 Method for preparing porous ceramic microballs by low-temperature coaxial electrostatic spraying
US20150299421A1 (en) * 2012-11-19 2015-10-22 The University Of Birmingham Production of Boron Carbide Powder
CN105017555A (en) * 2014-04-29 2015-11-04 中国科学院化学研究所 Cellulose aerogel and preparation method for hybrid aerogel thereof
CN106044752A (en) * 2016-05-27 2016-10-26 江苏省特种设备安全监督检验研究院 Method for preparing high orientation graphene aerogel

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102898174A (en) * 2011-07-29 2013-01-30 深圳光启创新技术有限公司 Porous ceramic microsphere material and preparation method thereof
US20150299421A1 (en) * 2012-11-19 2015-10-22 The University Of Birmingham Production of Boron Carbide Powder
CN103204695A (en) * 2013-03-11 2013-07-17 西安理工大学 Method for preparing porous ceramic microballs by low-temperature coaxial electrostatic spraying
CN105017555A (en) * 2014-04-29 2015-11-04 中国科学院化学研究所 Cellulose aerogel and preparation method for hybrid aerogel thereof
CN106044752A (en) * 2016-05-27 2016-10-26 江苏省特种设备安全监督检验研究院 Method for preparing high orientation graphene aerogel

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115159535A (en) * 2022-07-29 2022-10-11 武汉科技大学 Magnesium aluminate spinel aerogel and preparation method thereof
CN115159535B (en) * 2022-07-29 2023-11-28 武汉科技大学 Magnesia-alumina spinel aerogel and preparation method thereof
CN115505255A (en) * 2022-09-22 2022-12-23 浙江大学 Boron nitride polymer composite material and preparation method and application thereof

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