Particle-based flexible high-temperature-resistant ceramic nanofiber membrane and preparation method thereof

Abstract

The invention discloses a particle-based flexible high-temperature-resistant ceramic nanofiber membrane and a preparation method thereof, and the preparation method comprises the following steps: adding ceramic nanoparticles and a dispersant into a water / ethanol mixed solution, stirring and dispersing for a period of time, then adding an alkaline regulator, then adding semi-gel silica sol, and continuously stirring and mixing uniformly to obtain the particle-based flexible high-temperature-resistant ceramic nanofiber membrane. A mixed solution is obtained; rapidly gelling and solidifying the surface of a spinning jet flow by utilizing a hot air flow-assisted electrostatic spinning technology, and keeping certain flowability in the jet flow so as to continuously draft and refine the jet flow to obtain a precursor fiber membrane; the obtained precursor fiber membrane is subjected to ultrafast Joule heat treatment and then transferred into a muffle furnace to be calcined, and finally the flexible high-temperature-resistant ceramic nanofiber membrane is obtained, so that the problems that in the preparation process of the ceramic nanofiber membrane, the solubility of metal salt is poor, the solution is unstable, few spinnable raw materials exist, and the crystallization firing temperature is high are solved; the bottleneck problems that an existing ceramic nanofiber membrane is prone to brittle fracture, low in temperature resistance and the like are also solved.

Description

Technical Field

[0001] This application belongs to the field of ceramic nanofiber material preparation technology, specifically relating to a method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane. Background Technology

[0002] Ceramic fibers, due to their excellent temperature resistance, thermal stability, thermal shock resistance, mechanical vibration resistance, low thermal conductivity, and chemical corrosion resistance, have been widely used in aerospace, defense, nuclear energy, petrochemical, and metallurgical fields. However, existing ceramic fibers generally have diameters on the order of micrometers, and are typically stiff and brittle, making efficient weaving difficult and limiting their application performance and functional expansion. Further reducing the diameter of ceramic fibers to the nanometer level can significantly improve their flexibility and high-temperature insulation properties. Electrospinning technology, with its simple equipment, wide range of spinnable raw materials, strong controllability of fiber structure, and ease of integration with other technologies, has become one of the effective methods for preparing ceramic nanofibers. Currently, more than 50 types of ceramic oxide nanofiber membranes have been prepared using electrospinning technology, exhibiting excellent application performance. Existing ceramic nanofibers are mainly prepared using inorganic or organic metal salts as raw materials; however, due to the limited solubility and hydrolysis of metal salts, their proportion in the fiber is generally low. Furthermore, polymeric spinning aids are commonly added to the precursor solution to improve the spinnability of the spinning solution. However, the introduction of polymeric spinning aids results in a low content of ceramic components in the precursor fiber membrane, leading to extremely low inorganic fiber yield. Moreover, the large amount of polymeric substances in the precursor fibers undergoes oxidative decomposition during annealing, causing structural instability and numerous defects in the ceramic nanofibers, making the fibers brittle and difficult to break, thus hindering the production of flexible ceramic nanofibers. Summary of the Invention

[0003] The purpose of this invention is to provide a particle-based flexible high-temperature resistant ceramic nanofiber membrane and its preparation method, which solves the problems of poor metal salt solubility, unstable solution, limited spinnable raw materials, and high crystallization firing temperature in the preparation of existing ceramic nanofiber membranes, as well as the bottleneck problems of easy brittle fracture and low temperature resistance of existing ceramic nanofiber membranes.

[0004] This invention uses one or more ceramic nanoparticles as raw materials to prepare a dispersion. By introducing semi-gel silica sol into the dispersion, excellent spinnability is imparted. Simultaneously, since no polymer is introduced into the precursor solution, the intact skeletal structure of the single fiber is avoided from being destroyed by the decomposition of a large number of organic components during calcination, ultimately yielding a flexible ceramic nanofiber membrane. First, semi-gel silica sol is added to a dispersion containing one or more ceramic nanoparticles. The incomplete network molecular chain structure in the semi-gel silica sol effectively improves the viscoelasticity and spinnability of the mixed solution. In the subsequent electrospinning process, a hot airflow-assisted spinning method is used to promote rapid gelation and solidification on the surface of the spinning jet, while maintaining a certain fluidity inside the jet to continue stretching and refining, thus preparing the precursor fiber membrane. Finally, the precursor fiber membrane is first subjected to ultrafast Joule heat treatment to achieve an instantaneous high-temperature reaction of the precursor fibers, instantly completing the formation and initial crystallization of the main crystalline phase, effectively inhibiting rapid grain growth and avoiding grain coarsening during slow heating. Subsequently, the fibers are transferred to a muffle furnace and calcined using the traditional programmed heating method. During the slow heating process, defects such as lattice distortion, microcracks, and pores in the ceramic fibers are repaired, residual stress is gently removed, and the flexibility and fatigue performance of the fibers are improved, thereby finally obtaining a flexible high-temperature resistant ceramic nanofiber membrane.

[0005] To solve the above problems, the present invention is achieved through the following technical solution: In a first aspect, the present invention provides a method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane, comprising the following steps: Step 1): Add one or more ceramic nanoparticles and a suitable dispersant to a mixed solution of ethanol and water, stir and disperse for 1-6 hours, and then add an alkaline regulator to make the pH value of the dispersion higher than the isoelectric point of the particles. Step 2): Add one or more silicon sources and catalysts to a mixed solution of ethanol and water, adjust the pH of the silica sol to make it in a semi-gel state, and then store it in an ice-water bath; Step 3): Mix the semi-gel silica sol obtained in Step 2) with the dispersion in Step 1), and continue stirring for 5-12 hours to ensure uniform mixing, thereby preparing a spinnable precursor solution; Step 4): The precursor spinning solution in Step 3) is subjected to hot airflow-assisted electrospinning to promote rapid gel solidification on the surface of the spinning jet, while the inside of the jet still maintains a certain fluidity to allow it to continue to be drawn and refined, thus preparing the precursor fiber membrane. Step 5): The precursor fiber membrane obtained in Step 4) is first subjected to ultrafast Joule heat treatment, and then transferred to a muffle furnace for further calcination to finally obtain a flexible high-temperature resistant ceramic nanofiber membrane.

[0006] Preferably, in step 1), the molybdenum salt is any one or more of ammonium molybdate, molybdenum pentachloride, molybdenum acetylacetonate, and phosphomolybdic acid hydrate; the cobalt salt is any one or more of cobalt acetate, cobalt acetylacetonate, cobalt nitrate hexahydrate, cobalt sulfate heptahydrate, and cobalt chloride hexahydrate; the solvent is one or more of water, methanol, ethanol, ethylene glycol, propanol, acetone, N,N-dimethylformamide, and N,N-dimethylacetamide; the molar ratio of molybdenum salt to cobalt salt is 1:1; and the ratio of molybdenum salt, cobalt salt, and solvent is 10g:25~100mL.

[0007] Preferably, in step 1), the ceramic nanoparticles are aluminum oxide, titanium oxide, vanadium oxide, germanium oxide, niobium pentoxide, hafnium oxide, zinc oxide, bismuth oxide, cobalt oxide, molybdenum oxide, tin oxide, tantalum oxide, zirconium oxide, tungsten oxide, nickel oxide, magnesium oxide, iron oxide, copper oxide, chromium oxide, yttrium oxide, lutetium oxide, terbium oxide, indium oxide, holmium trioxide, scandium trioxide, samarium trioxide, praseodymium oxide, neodymium trioxide, lanthanum trioxide, gadolinium trioxide, gallium trioxide, dysprosium trioxide, cerium dioxide, zirconium carbide, tungsten carbide, vanadium carbide, titanium carbide, tantalum carbide, silicon carbide, niobium carbide, molybdenum carbide, manganese carbide, hafnium carbide, chromium carbide, boron carbide, and aluminum carbide. Boron nitride, hafnium nitride, niobium nitride, vanadium nitride, yttrium nitride, tantalum nitride, zirconium nitride, titanium nitride, silicon nitride, magnesium nitride, chromium nitride, aluminum nitride, tungsten pentaboride, chromium monoboride, vanadium monoboride, nickel diboride, molybdenum diboride, manganese diboride, magnesium diboride, chromium diboride, tungsten diboride, vanadium diboride, silicon hexaboride, hafnium diboride, calcium hexaboride, zirconium diboride, titanium diboride, lanthanum hexaboride, tin titanium carbide, titanium aluminum carbide, aluminum titanium carbide, aluminum niobium carbide, aluminum vanadium carbide, silicon titanium carbide, molybdenum disulfide, tungsten disulfide, titanium dihydrogenide, zirconium dihydrogenide, hafnium dihydrogenide, tungsten silicide, tantalum disilicide, zirconium disilicide, molybdenum disilicide, titanium disilicide, hafnium disilicide; The average particle size of the nanoparticles is 20~200 nm; The ratio of ceramic nanoparticles to dispersant is 100g:(1~15)g, and the ratio of ceramic nanoparticles to a mixed solution of ethanol and water is 10g:(5~30)mL. The dispersant is any one or more of the following: sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, dodecylbenzenesulfonic acid, ammonium dodecyl sulfate, dodecyl phosphate, sodium stearate, sodium lauryl sulfate, hexadecyltrimethylammonium bromide, benzalkonium chloride, dioctadecyl dimethylammonium chloride, dodecyl dimethyl benzyl ammonium chloride, octadecyl trimethylammonium chloride, hexadecyl pyridine bromide, sodium dodecyl aminopropionate, dodecyl dimethyl betaine, sodium lauroyl sarcosinate, and sorbitan monolaurate. The alkalinity regulator is one or more of sodium hydroxide, potassium hydroxide, ammonia, sodium carbonate, and sodium bicarbonate.

[0008] Preferably, in step 2), the zirconium salt is any one or more of zirconium acetate, zirconium n-propoxide, zirconium n-butoxide, zirconium acetylacetone, basic zirconium carbonate, zirconium nitrate pentahydrate, and zirconium oxychloride octahydrate; the ligand is any one or more of ethylenediaminetetraacetic acid, acetylacetone, acetic acid, citric acid, tartaric acid, and diethanolamine; the ratio of zirconium salt to solvent is 5g:(5~50)mL; and the molar ratio of zirconium salt to ligand is 1:1 to 1:10.

[0009] Preferably, in step 2), the silicon source is any one or more of tetramethyl silicate, tetraethyl silicate, vinyltrimethoxysilane, vinyltriethoxysilane, methyltriethoxysilane, 3-chloropropyltrichlorosilane, 3-chloropropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, and γ-aminopropyltriethoxysilane. The catalyst is any one or more of hydrochloric acid, phosphoric acid, sulfuric acid, acetic acid, oxalic acid, formic acid, and propionic acid. The ratio of the silicon source to the mixed solution of ethanol and water is 10g:(5~60)mL; the ratio of ethanol to water is (0~60)mL:(0~60)mL.

[0010] Preferably, in step 3), the ratio of the semi-gel silica sol to the dispersion is (1~20) g: 100 mL; and the dynamic viscosity of the precursor solution is 1~30 Pa·s.

[0011] Preferably, in step 4), the process parameters for hot airflow-assisted electrospinning are: the pressure of the auxiliary airflow is 0.02~0.7MPa, the gas flow rate is 5~100L / min, the airflow temperature is 30~80℃, the ambient temperature is 20~40℃, the ambient relative humidity is 20~60%, the voltage is 15~60kV, the distance between the receiving device and the spinneret is 20~50cm, and the injection speed is 0.1~10mL / h. In step 5), the process parameters for the Joule heat treatment are: voltage 15-30V, current 50-250A, and heating time 100ms-1min.

[0012] Preferably, the heating rate of the muffle furnace is 0.5~10℃ / min, the maximum calcination temperature is 900~1700℃, and the maximum temperature is maintained for 10~180min.

[0013] Secondly, the present invention provides a particle-based flexible high-temperature resistant ceramic nanofiber membrane, wherein the average diameter of the fibers in the particle-based flexible high-temperature resistant ceramic nanofiber membrane is 100~1000nm, the average grain size inside the fibers is 5~60nm, the softness of the fiber membrane is 30~150mN, and the fiber membrane does not break after being repeatedly bent and folded 10,000 times.

[0014] Preferably, the particulate-based flexible high-temperature resistant ceramic nanofiber membrane can withstand temperatures of over 1100°C over a long period of time.

[0015] The principle of this invention is as follows: Traditional electrospinning for ceramic fiber preparation relies on incorporating a large amount of high-molecular polymers into the sol to provide the necessary chain entanglement and viscoelasticity, ensuring stable jet stretching. However, these organic compounds decompose and escape violently during subsequent high-temperature calcination, generating numerous pores and cracks within the fiber, and even causing fiber structural collapse, severely impairing its mechanical properties and density. Unlike traditional methods, this invention uses ceramic nanoparticles as the metal source and a semi-gelatinous silica sol with an incomplete three-dimensional network molecular structure as the spinning aid. The numerous silanol groups in the semi-gelatinous silica sol can undergo reversible destruction and reconstruction under shear force, thus providing the dispersion with viscoelasticity similar to a polymer solution. The silanol groups in the semi-gelatinous silica sol can undergo physical adsorption or chemical bonding with the surface of various ceramic nanoparticles, contributing to the uniform dispersion of nanoparticles in the spinning solution. During electrospinning, this invention introduces a temperature-controlled hot gas flow around the spinning needle. During the stretching process, the surface solvent of the jet is rapidly evaporated by the hot gas flow, while simultaneously accelerating the condensation reaction of the semi-gelled silica sol on the surface, achieving rapid gelation and solidification of the spinning jet surface into fibers. This rigid silica gel shell provides the jet with immediate mechanical strength, suppressing Rayleigh instability and whiplash, and significantly improving the stability of the spinning process. Since heat conduction from the outside to the inside takes time, the interior of the jet maintains a high solvent content and fluidity for a short period. Under the continuous action of the electric field, the unsolidified core inside the jet can continue to be stretched and refined, thereby preparing precursor fibers with smaller diameters and better uniformity. In the subsequent heat treatment process, the precursor fiber membrane is first subjected to ultrafast Joule heat treatment. The extremely high heating rate allows the precursor fibers to rapidly cross the decomposition temperature range, directly driving the rapid formation of the ceramic main crystalline phase, achieving instantaneous ceramicization and preliminary densification of the fiber skeleton. Subsequently, the fibers are transferred to a muffle furnace and calcined using the traditional programmed heating method. During the slow heating process, defects such as lattice distortion, microcracks, and pores in the ceramic fibers are eliminated, and the residual stress in the ceramic fibers is gently relaxed, improving the flexibility and fatigue performance of the fibers, thereby finally obtaining a flexible high-temperature resistant ceramic nanofiber membrane.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention provides a particle-based flexible high-temperature resistant ceramic nanofiber membrane, which solves the problems of poor metal salt solubility, unstable solution, limited spinnable raw materials, and high crystallization firing temperature in the preparation process of existing ceramic nanofiber membranes, as well as the bottleneck problems of easy brittle fracture and low temperature resistance of existing ceramic nanofiber membranes.

[0017] (2) The particle-based flexible high-temperature resistant ceramic nanofiber membrane of the present invention has excellent flexibility and high temperature resistance. Attached Figure Description

[0018] Figure 1 The morphology of the particle-based flexible high-temperature resistant ceramic nanofiber membrane prepared in this invention is shown in (1). Figure 2 The morphology diagram (2) of the particle-based flexible high-temperature resistant ceramic nanofiber membrane prepared in this invention is shown. Figure 3 The morphology of the particle-based flexible high-temperature resistant ceramic nanofiber membrane prepared in this invention is shown in Figure (3). Detailed Implementation

[0019] To make the present invention more apparent and understandable, preferred embodiments are described in detail below.

[0020] Example 1 A method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane includes the following steps: Step 1): Zirconia nanoparticles and sodium dodecyl sulfate were added to a mixed solution of ethanol and water. After stirring for 3 hours, ammonia was added to make the pH of the dispersion higher than the isoelectric point of the particles. The average particle size of the zirconia nanoparticles was 40 nm. The ratio of zirconia nanoparticles to dispersant was 100 g: 10 g. The ratio of zirconia nanoparticles to the mixed solution of ethanol and water was 10 g: 20 mL. Step 2): Add tetraethyl silicate to a mixed solution of ethanol and water, and use hydrochloric acid to adjust the pH of the silica sol to make it in a semi-gel state. Then store it in an ice-water bath. The ratio of tetraethyl silicate to the mixed solution of ethanol and water is 10g:5mL; the ratio of ethanol to water is 1:1.

[0021] Step 3): Mix the semi-gel silica sol obtained in Step 2) with the zirconium oxide nanoparticle dispersion in Step 1), and continue stirring for 6 hours to ensure uniform mixing, thus preparing a spinnable precursor solution. The ratio of the semi-gel silica sol to the dispersion is 10 g: 100 mL; the dynamic viscosity of the precursor solution is 16 Pa·s.

[0022] Step 4): The precursor spinning solution from Step 3) is subjected to hot airflow-assisted electrospinning, which promotes rapid gelation and solidification on the surface of the spinning jet, while maintaining a certain fluidity inside the jet to continue stretching and refining, thus preparing the precursor fiber membrane. The process parameters for hot airflow-assisted electrospinning are as follows: the pressure of the auxiliary airflow is 0.4 MPa, the gas flow rate is 20 L / min, the airflow temperature is 60℃, the ambient temperature is 30℃, the ambient relative humidity is 40%, the voltage is 30 kV, the distance between the receiving device and the spinneret is 28 cm, and the infusion rate is 2 mL / h.

[0023] Step 5): The precursor fiber membrane obtained in Step 4) is first subjected to ultrafast Joule heat treatment, and then transferred to a muffle furnace for further calcination to finally obtain a flexible high-temperature resistant ceramic nanofiber membrane. The process parameters for Joule heat treatment are: voltage 30V, current 120A, heating time 200ms; the heating rate of the muffle furnace is 5℃ / min, the maximum calcination temperature is 1200℃, and it is held at the maximum temperature for 120min.

[0024] The zirconia particle-based ceramic nanofibers prepared above have an average diameter of 500 nm, an average grain size of 35 nm, a fiber membrane flexibility of 70 mN, and do not break after 10,000 repeated bending and folding. The fiber morphology is as follows. Figure 1 As shown.

[0025] Example 2 A method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane includes the following steps: Step 1): Add lutetium oxide nanoparticles and hexadecyltrimethylammonium bromide to a mixed solution of ethanol and water, stir for 4 hours, and then add sodium hydroxide to make the pH of the dispersion higher than the isoelectric point of the particles; the average particle size of the lutetium oxide nanoparticles is 50 nm, the ratio of lutetium oxide nanoparticles to dispersant is 100 g: 15 g, and the ratio of lutetium oxide nanoparticles to the mixed solution of ethanol and water is 10 g: 20 mL. Step 2): Add γ-mercaptopropyltrimethoxysilane to a mixed solution of ethanol and water, and use acetic acid to adjust the pH of the silica sol to make it in a semi-gel state. Then store it in an ice-water bath. The ratio of γ-mercaptopropyltrimethoxysilane to the mixed solution of ethanol and water is 10g:8mL; the ratio of ethanol to water is 1:1.

[0026] Step 3): Mix the semi-gel silica sol obtained in Step 2) with the lutetium oxide nanoparticle dispersion in Step 1), and continue stirring for 12 hours to ensure uniform mixing, thus preparing a spinnable precursor solution. The ratio of the semi-gel silica sol to the dispersion is 15 g: 100 mL; the dynamic viscosity of the precursor solution is 12 Pa·s.

[0027] Step 4): The precursor spinning solution from Step 3) is subjected to hot airflow-assisted electrospinning, which promotes rapid gelation and solidification on the surface of the spinning jet, while maintaining a certain fluidity inside the jet to continue stretching and refining, thus preparing the precursor fiber membrane. The process parameters for hot airflow-assisted electrospinning are as follows: the pressure of the auxiliary airflow is 0.2 MPa, the gas flow rate is 10 L / min, the airflow temperature is 50℃, the ambient temperature is 30℃, the ambient relative humidity is 45%, the voltage is 35 kV, the distance between the receiving device and the spinneret is 25 cm, and the infusion rate is 3 mL / h.

[0028] Step 5): The precursor fiber membrane obtained in Step 4) is first subjected to ultrafast Joule heat treatment, and then transferred to a muffle furnace for further calcination to finally obtain a flexible high-temperature resistant ceramic nanofiber membrane. The process parameters for Joule heat treatment are: voltage 15V, current 100A, heating time 300ms; the heating rate of the muffle furnace is 10℃ / min, the maximum calcination temperature is 1100℃, and it is held at the maximum temperature for 60min.

[0029] The lutetium oxide particle-based ceramic nanofibers prepared above have an average diameter of 560 nm, an average grain size of 42 nm, a fiber membrane flexibility of 80 mN, and do not break after 10,000 repeated bending and folding. The fiber morphology is as follows. Figure 2 As shown.

[0030] Example 3 A method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane includes the following steps: Step 1): Add aluminum nitride nanoparticles and sodium dodecylaminopropionate to a mixed solution of ethanol and water, stir for 6 hours, and then add potassium hydroxide to make the pH value of the dispersion higher than the isoelectric point of the particles; the average particle size of the aluminum nitride nanoparticles is 60 nm, the ratio of aluminum nitride nanoparticles to dispersant is 100 g: 12 g, and the ratio of aluminum nitride nanoparticles to the mixed solution of ethanol and water is 10 g: 30 mL. Step 2): Add vinyltriethoxysilane to a mixed solution of ethanol and water, and use oxalic acid to adjust the pH of the silica sol to make it semi-gel state. Then store it in an ice-water bath. The ratio of vinyltriethoxysilane to the mixed solution of ethanol and water is 16g:20mL; the ratio of ethanol to water is 2:1.

[0031] Step 3): Mix the semi-gel silica sol obtained in Step 2) with the aluminum nitride nanoparticle dispersion in Step 1), and continue stirring for 4 hours to ensure uniform mixing, thus preparing a spinnable precursor solution. The ratio of the semi-gel silica sol to the dispersion is 15 g: 100 mL; the dynamic viscosity of the precursor solution is 22 Pa·s.

[0032] Step 4): The precursor spinning solution from Step 3) is subjected to hot airflow-assisted electrospinning, which promotes rapid gelation and solidification on the surface of the spinning jet, while maintaining a certain fluidity inside the jet to continue stretching and refining, thus preparing the precursor fiber membrane. The process parameters for hot airflow-assisted electrospinning are: auxiliary airflow pressure of 0.2 MPa, gas flow rate of 50 L / min, airflow temperature of 55℃, ambient temperature of 25℃, ambient relative humidity of 46%, voltage of 35 kV, distance between the receiving device and the spinneret of 25 cm, and infusion rate of 1 mL / h.

[0033] Step 5): The precursor fiber membrane obtained in Step 4) is first subjected to ultrafast Joule heat treatment, and then transferred to a muffle furnace for further calcination to finally obtain a flexible high-temperature resistant ceramic nanofiber membrane. The process parameters for Joule heat treatment are: voltage 30V, current 180A, heating time 500ms; the heating rate of the muffle furnace is 10℃ / min, the maximum calcination temperature is 1500℃, and it is held at the maximum temperature for 30min.

[0034] The aluminum nitride particle-based ceramic nanofibers prepared above have an average diameter of 420 nm, an average grain size of 43 nm, a fiber membrane flexibility of 50 mN, and do not break after 10,000 repeated bending and folding. The fiber morphology is as follows. Figure 3 As shown.

[0035] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a particulate-based flexible high-temperature resistant ceramic nanofiber membrane, characterized in that, Includes the following steps: Step 1): Add one or more ceramic nanoparticles and a suitable dispersant to a mixed solution of ethanol and water, stir and disperse for 1-6 hours, and then add an alkaline regulator. Step 2): Add one or more silicon sources and catalysts to a mixed solution of ethanol and water, adjust the pH of the silica sol to make it in a semi-gel state, and then store it in an ice-water bath; Step 3): Mix the semi-gel silica sol obtained in Step 2) with the dispersion in Step 1), and continue stirring for 5-12 hours to ensure uniform mixing, thereby preparing a spinnable precursor solution; Step 4): The precursor spinning solution in Step 3) is subjected to hot airflow-assisted electrospinning to promote rapid gel solidification on the surface of the spinning jet, while the inside of the jet still maintains a certain fluidity to allow it to continue to be drawn and refined, thus preparing the precursor fiber membrane. Step 5): The precursor fiber membrane obtained in Step 4) is first subjected to ultrafast Joule heat treatment, and then transferred to a muffle furnace for further calcination to finally obtain a flexible high-temperature resistant ceramic nanofiber membrane.

2. The method for preparing a particulate-based flexible high-temperature resistant ceramic nanofiber membrane according to claim 1, characterized in that, In step 1), the ceramic nanoparticles are aluminum oxide, titanium oxide, vanadium oxide, germanium oxide, niobium pentoxide, hafnium oxide, zinc oxide, bismuth oxide, cobalt oxide, molybdenum oxide, tin oxide, tantalum oxide, zirconium oxide, tungsten oxide, nickel oxide, magnesium oxide, iron oxide, copper oxide, chromium oxide, yttrium oxide, lutetium oxide, terbium oxide, indium oxide, holmium trioxide, scandium trioxide, samarium trioxide, praseodymium oxide, neodymium trioxide, lanthanum trioxide, gadolinium trioxide, gallium trioxide, dysprosium trioxide, cerium dioxide, zirconium carbide, tungsten carbide, vanadium carbide, titanium carbide, tantalum carbide, silicon carbide, niobium carbide, molybdenum carbide, manganese carbide, hafnium carbide, chromium carbide, boron carbide, aluminum carbide, and nitrogen. The following are all of the following: boron nitride, hafnium nitride, niobium nitride, vanadium nitride, yttrium nitride, tantalum nitride, zirconium nitride, titanium nitride, silicon nitride, magnesium nitride, chromium nitride, aluminum nitride, tungsten pentaboride, chromium monoboride, vanadium monoboride, nickel diboride, molybdenum diboride, manganese diboride, magnesium diboride, chromium diboride, tungsten diboride, vanadium diboride, silicon hexaboride, hafnium diboride, calcium hexaboride, zirconium diboride, titanium diboride, lanthanum hexaboride, tin titanium carbide, titanium aluminum carbide, aluminum titanium carbide, aluminum niobium carbide, aluminum vanadium carbide, silicon titanium carbide, molybdenum disulfide, tungsten disulfide, titanium dihydrogenide, zirconium dihydrogenide, hafnium dihydrogenide, tungsten silicide, tantalum disilicide, zirconium disilicide, molybdenum disilicide, titanium disilicide, hafnium disilicide; The average particle size of the nanoparticles is 20~200 nm; The ratio of ceramic nanoparticles to dispersant is 100g:(1~15)g, and the ratio of ceramic nanoparticles to a mixed solution of ethanol and water is 10g:(5~30)mL. The dispersant is any one or more of the following: sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, dodecylbenzenesulfonic acid, ammonium dodecyl sulfate, dodecyl phosphate, sodium stearate, sodium lauryl sulfate, hexadecyltrimethylammonium bromide, benzalkonium chloride, dioctadecyl dimethylammonium chloride, dodecyl dimethyl benzyl ammonium chloride, octadecyl trimethylammonium chloride, hexadecyl pyridine bromide, sodium dodecyl aminopropionate, dodecyl dimethyl betaine, sodium lauroyl sarcosinate, and sorbitan monolaurate. The alkalinity regulator is one or more of sodium hydroxide, potassium hydroxide, ammonia, sodium carbonate, and sodium bicarbonate.

3. The method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane according to claim 1, characterized in that, In step 2), the zirconium salt is any one or more of zirconium acetate, zirconium n-propoxide, zirconium n-butoxide, zirconium acetylacetone, basic zirconium carbonate, zirconium nitrate pentahydrate, and zirconium oxychloride octahydrate; the ligand is any one or more of ethylenediaminetetraacetic acid, acetylacetone, acetic acid, citric acid, tartaric acid, and diethanolamine; the ratio of zirconium salt to solvent is 5g:(5~50)mL; and the molar ratio of zirconium salt to ligand is 1:1 to 1:

10.

4. The method for preparing a particulate-based flexible high-temperature resistant ceramic nanofiber membrane according to claim 1, characterized in that, In step 2), the silicon source is any one or more of tetramethyl silicate, tetraethyl silicate, vinyltrimethoxysilane, vinyltriethoxysilane, methyltriethoxysilane, 3-chloropropyltrichlorosilane, 3-chloropropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, and γ-aminopropyltriethoxysilane. The catalyst is any one or more of hydrochloric acid, phosphoric acid, sulfuric acid, acetic acid, oxalic acid, formic acid, and propionic acid. The ratio of the silicon source to the mixed solution of ethanol and water is 10g:(5~60)mL; the ratio of ethanol to water is (0~60)mL:(0~60)mL.

5. The method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane according to claim 1, characterized in that, In step 3), the ratio of the semi-gel silica sol to the dispersion is (1~20) g: 100 mL; the dynamic viscosity of the precursor solution is 1~30 Pa·s.

6. The method for preparing a particle-based flexible high-temperature resistant ceramic nanofiber membrane according to claim 1, characterized in that, In step 4), the process parameters for hot airflow-assisted electrospinning are as follows: the pressure of the auxiliary airflow is 0.02~0.7MPa, the gas flow rate is 5~100L / min, the airflow temperature is 30~80℃, the ambient temperature is 20~40℃, the ambient relative humidity is 20~60%, the voltage is 15~60kV, the distance between the receiving device and the spinneret is 20~50cm, and the injection speed is 0.1~10mL / h. In step 5), the process parameters for the Joule heat treatment are: voltage 15-30V, current 50-250A, and heating time 100ms-1min.

7. The method for preparing a particulate-based flexible high-temperature resistant ceramic nanofiber membrane according to claim 1, characterized in that, The muffle furnace has a heating rate of 0.5~10℃ / min, a maximum calcination temperature of 900~1700℃, and is maintained at the maximum temperature for 10~180min.

8. The particulate-based flexible high-temperature resistant ceramic nanofiber membrane prepared by the method according to any one of claims 1-7, characterized in that, The average diameter of the fibers in the particle-based flexible high-temperature resistant ceramic nanofiber membrane is 100~1000nm, the average grain size inside the fibers is 5~60nm, the flexibility of the fiber membrane is 30~150mN, and the fiber membrane does not break after 10,000 repeated bending and folding.

9. The particulate-based flexible high-temperature resistant ceramic nanofiber membrane according to claim 8, characterized in that, The particle-based flexible high-temperature resistant ceramic nanofiber membrane can withstand temperatures above 1100℃ for extended periods.

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