A low-oxygen hafnium titanium carbon ceramic precursor and a preparation method thereof

Abstract

The application provides a hafnium-titanium-carbon ceramic precursor and a preparation method thereof, and belongs to the technical field of ceramic materials. The method comprises the following steps: under the protection of nitrogen, reacting dichlorobis-cyclopentadienyl hafnium and reagent 1, and performing suction filtration to obtain hafnium intermediate 1; under the protection of nitrogen, stirring dichlorobis-cyclopentadienyl hafnium, reagent 2 and polyolefin to obtain hafnium intermediate 2; under anhydrous and anaerobic conditions, reacting organic solvent, hafnium intermediate 1 and hafnium intermediate 2 to obtain alkyl hafnium; under the protection of nitrogen, reacting dichlorobis-cyclopentadienyl titanium and reagent 1, and performing suction filtration to obtain titanium intermediate 1; under the protection of nitrogen, reacting dichlorobis-cyclopentadienyl titanium, reagent 2 and polyolefin under the action of hydrogen to obtain titanium intermediate 2; under anhydrous and anaerobic conditions, reacting organic solvent, titanium intermediate 1 and titanium intermediate 2 to obtain alkyl titanium; and stirring alkyl hafnium, organic solvent and alkyl titanium, heating and performing suction filtration under reduced pressure. The hafnium-titanium-carbon ceramic precursor provided by the application has a low oxygen content.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of ceramic materials, and in particular to a low-oxygen hafnium-titanium-carbon ceramic precursor and a preparation method thereof. BACKGROUND

[0002] The development of a new generation of aircraft has attracted widespread attention to superhigh-temperature ablation-resistant materials. When a hypersonic aircraft is raised to more than 10 Mach numbers, key components such as the leading edge generate extremely high temperatures (more than 2000 DEG C) due to intense friction, accompanied by strong oxidation and airflow scouring environment. Current ceramic matrix composites with silicon carbide as the matrix are difficult to meet such high-temperature use environment. Therefore, the matrix component of the ceramic matrix composite needs to be improved.

[0003] Compared with single-phase ceramics, mixed refractory metal ceramic materials often have higher mechanical properties and better oxidation resistance, and are expected to become candidate materials for high-temperature structural components of future higher Mach number aircrafts. Among carbide ceramics, hafnium carbide and titanium carbide have obvious advantages in melting point. Under high-temperature conditions with oxygen, the surface of hafnium carbide generates hafnium dioxide with a higher melting point and a dense compound HfO x C y , thus having good oxidation resistance. Titanium carbide has excellent physical and chemical properties such as high melting point, high hardness, high elastic modulus, good electrical and thermal conductivity, chemical corrosion resistance, high temperature resistance, high strength and good thermal shock resistance.

[0004] Currently, common processes for preparing fiber-toughened ceramic matrix composites mainly include slurry impregnation, chemical vapor deposition, reactive melt infiltration and precursor impregnation and pyrolysis. Compared with other processes, the precursor impregnation and pyrolysis (PIP) method has a lower preparation temperature, can effectively reduce the possibility of damaging the fiber preform and realize the improvement of the mechanical properties of the composite material. In addition, the method is more conducive to obtaining a completely chemically uniform solid solution ceramic. The low-oxygen hafnium-containing precursor and the titanium-containing precursor obtained by the PIP method have stable properties and high ceramic conversion rate. Since hafnium carbide and titanium carbide have the same crystal form, the two can easily form a solid solution. The use of transition metal Ti element to replace Hf element to prepare a solid solution can remain stable at high temperatures, and the initial melting temperature is close to 2800 DEG C. In addition, with the increase of the proportion of Ti element, the initial melting temperature of the solid solution does not decrease linearly. In addition, proper addition of Ti element can realize the transition of the composite material from intergranular fracture to string crystal fracture at high temperatures, so that the performance of the composite material does not decrease but increases at high temperatures, effectively improving the mechanical properties of the composite material at high temperatures. SUMMARY

[0005] Therefore, one of the purposes of the present application is to overcome the shortcomings of the prior art and provide a preparation method of a low-oxygen hafnium titanium carbon ceramic precursor.

[0006] One of the purposes of the present application is to provide a low-oxygen hafnium titanium carbon ceramic precursor.

[0007] In order to achieve one of the above purposes, the present application adopts the following technical solutions:

[0008] A preparation method of a low-oxygen hafnium titanium carbon ceramic precursor, the preparation method comprising the following steps:

[0009] Step S1, under the protection of nitrogen, stirring and dispersing dichlorobis hafniumocene, then dropping reagent 1 into dichlorobis hafniumocene at-10 to-5℃, then warming to 0 to 50℃ for 2 to 6h, and then filtering to obtain hafnium intermediate 1;

[0010] In the step S1, the mass ratio of dichlorobis hafniumocene and reagent 1 is 1:3 to 34;

[0011] Step S2, under the protection of nitrogen, stirring and dispersing dichlorobis hafniumocene, then dropping reagent 2 into dichlorobis hafniumocene at-25 to-20℃, then passing hydrogen for 1 to 4h, then adding polyolefin with a molecular weight of 5500 to 20000 after filtering, and then warming to 78 to 82℃ to obtain hafnium intermediate 2;

[0012] In the step S2, the mass ratio of dichlorobis hafniumocene, reagent 2 and polyolefin is 1:1 to 40:1 to 200;

[0013] Step S3, under the conditions of no water and no oxygen, mixing organic solvent, hafnium intermediate 1 and hafnium intermediate 2, and then reacting at 57 to 62℃ for 2 to 6h to obtain alkyl hafniumocene;

[0014] In the step S3, the mass ratio of organic solvent, hafnium intermediate 1 and hafnium intermediate 2 is 1 to 15:1 to 4:1;

[0015] Step S4, under the protection of nitrogen, stirring and dispersing dichlorobis titaniumocene, then dropping reagent 1 into dichlorobis titaniumocene at-10 to-5℃, then warming to 0 to 50℃ for 2 to 6h, and then filtering to obtain titanium intermediate 1;

[0016] In the step S4, the mass ratio of dichlorobis titaniumocene and reagent 1 is 1:3 to 34;

[0017] Step S5, under the protection of nitrogen, after stirring and dispersing the titanium dichloride, the reagent 2 is added dropwise into the titanium dichloride at-25 to-20℃, hydrogen is introduced for 1 to 4 hours, and then the polyolefin with a molecular weight of 5500 to 20000 is added after filtration, and the temperature is increased to 78 to 82℃ to obtain the titanium intermediate 2;

[0018] In the step S5, the mass ratio of the titanium dichloride, the reagent 2 and the polyolefin is 1:1-40:1-200;

[0019] Step S6, under the conditions of anhydrous and anaerobic, the organic solvent, the titanium intermediate 1 and the titanium intermediate 2 are mixed, and then reacted at 57 to 62℃ for 2 to 6 hours to obtain the alkyl cyclopentadienyl titanium;

[0020] In the step S6, the mass ratio of the organic solvent, the titanium intermediate 1 and the titanium intermediate 2 is 1-15:1-4:1;

[0021] Step S7, the alkyl cyclopentadienyl hafnium and the organic solvent are mixed and stirred to a suspended state, and then cooled to-10℃, and then the alkyl cyclopentadienyl titanium is added, and stirred at-12 to-8℃ for 0.8 to 1.2 hours, and then the temperature is increased to room temperature, and then the low-oxygen hafnium titanium carbon precursor is obtained after filtration under reduced pressure;

[0022] In the step S7, the mass ratio of the alkyl cyclopentadienyl hafnium, the alkyl cyclopentadienyl titanium and the organic solvent is 1-9:9-1:9-900.

[0023] The structural formula of the alkyl cyclopentadienyl hafnium of the present application is as follows:

[0024]

[0025] In the formula, R is one or more of methane, ethane, n-propane, isopropane, n-butane, isobutane and n-pentane; and R1 is one or more of ethenyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl and isopentenyl.

[0026] The structural formula of the alkyl cyclopentadienyl titanium of the present application is as follows:

[0027]

[0028] In the formula, R is one or more of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and n-pentyl; and R1 is one or more of ethenyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, n-pentenyl and isopentenyl.

[0029] The application makes the crystal forms of hafnium carbide in alkyl hafnium and titanium carbide in alkyl titanium the same, so that the alkyl hafnium and the alkyl titanium are easy to form a solid solution after mixing, ensuring the composite material from intercrystalline fracture to twinned crystal fracture at high temperature, reducing the damage of the fiber preform, realizing the high-temperature performance not decreasing but increasing, improving the oxygen resistance and high-temperature mechanical properties of the composite material, and high ceramic conversion rate.

[0030] Further, in the step S1, the mass ratio of the hafnium dichloride and the reagent 1 is 1:6-30; preferably 1:12-24; preferably 17-21;

[0031] In the step S4, the mass ratio of the titanium dichloride and the reagent 1 is 1:6-30; preferably 1:12-24; preferably 17-21.

[0032] Further, in the step S1 and the step S4, the reagent 1 is one or more of formic acid, tetrahydrofuran, acetone, chloroform, dichloromethane, chloroform, acetylacetone, n-hexane, cyclohexane, acetonitrile, N,N-dimethylformamide, N,N-dimethylacetamide, carbon tetrachloride, methanol, ethanol, isopropanol, tert-butyl alcohol, toluene, xylene, ethylenediamine.

[0033] Further, in the step S2, in the step S2, the mass ratio of the hafnium dichloride, the reagent 2 and the polyolefin is 1:5-35:20-180; preferably 1:10-30:50-150; preferably 1:15-25:80-120;

[0034] In the step S5, the mass ratio of the titanium dichloride, the reagent 2 and the polyolefin is 1:5-35:20-180; preferably 1:10-30:50-150; preferably 1:15-25:80-120.

[0035] Further, in the step S2 and the step S5, the molecular weight of the polyolefin is 12000-16000; preferably 13000-14000.

[0036] Further, in the step S2 and the step S5, the reagent 2 is one or more of methyl lithium, ethyl lithium, propyl lithium, butyl lithium, vinyl bromide magnesium, n-propenyl bromide magnesium, isopropenyl bromide magnesium, n-butyl bromide magnesium, isobutyl bromide magnesium, n-pentenyl bromide magnesium, isopentenyl bromide magnesium;

[0037] In the step S2 and the step S5, the polyolefin is one or more of polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, poly-1-pentene, poly-1-hexene, poly-1-octene.

[0038] Further, in the step S3, the mass ratio of the organic solvent, hafnium intermediate 1 and hafnium intermediate 2 is 5-10:2-3:1;

[0039] In the step S6, the mass ratio of the organic solvent, titanium intermediate 1 and titanium intermediate 2 is 5-10:2-3:1;

[0040] In the step S7, the mass ratio of the alkyl hafnium metallocene, alkyl titanium metallocene and organic solvent is 3-6:7-2:100-700.

[0041] Further, in the step S3, step S6 and step S7, the organic solvent is one or more of benzene, toluene, dichloromethane, tetrahydrofuran, anhydrous diethyl ether, DMF, anhydrous methanol, anhydrous ethanol, ethyl acetate, N-methyl pyrrolidone.

[0042] In order to achieve the above-mentioned purpose two, the application adopts the following technical solutions to achieve the above-mentioned purpose two:

[0043] A low-oxygen hafnium titanium carbon ceramic precursor, characterized in that the low-oxygen hafnium titanium carbon ceramic precursor is prepared by the preparation method of the low-oxygen hafnium titanium carbon ceramic precursor.

[0044] The application has the following beneficial effects:

[0045] The application utilizes the hafnium carbide and titanium carbide with the same crystal form, so that the alkyl hafnium material containing hafnium carbide and the alkyl titanium material containing titanium carbide are mixed to easily form a solid solution, thereby reducing the oxygen content of the hafnium titanium carbon ceramic precursor, and the oxygen content is 2.22-2.31wt%. The process is simple and controllable, the ratio of the refractory metals in the hafnium titanium carbon precursor is adjustable, the ceramic conversion rate and thermal stability are good, the mechanical properties of the composite material are excellent, and the composite material can be used to prepare high-temperature resistant coatings, fiber reinforced bodies and ceramic matrix composite substrates, and has a wide application prospect in the field of ablation resistance. BRIEF DESCRIPTION OF DRAWINGS

[0046] Fig. 1 It is a scanning electron microscope graph of the low-oxygen hafnium titanium carbon precursor in Example 1 at 1400℃ ceramic product;

[0047] Fig. 2 It is a TGA curve graph of the low-oxygen hafnium titanium carbon precursor in Example 1;

[0048] Fig. 3 It is a DSC curve graph of the low-oxygen hafnium titanium carbon precursor in Example 1. DETAILED DESCRIPTION

[0049] The application will be further described below in combination with the drawings and specific embodiments.

[0050] Example 1:

[0051] (1) Preparation of alkyl metallocene hafnium

[0052] Under the protection of nitrogen, hafnium intermediate 1 was obtained by stirring and dispersing hafnium dichloride in a 250 mL three-necked flask, slowly adding formic acid at -10°C, and then reacting at 0°C for 2 h. The mass ratio of hafnium dichloride to formic acid was 1:3.

[0053] Under the protection of nitrogen, hafnium intermediate 2 was obtained by stirring and dispersing hafnium dichloride in a 250 mL three-necked flask, slowly dropping methyl lithium into hafnium dichloride at -25°C, bubbling hydrogen, stirring for 1 h, filtering the reaction solution, adding polyethylene with a molecular weight of 10000, slowly heating to 78°C, and reacting for 1.5 h. The mass ratio of hafnium dichloride, methyl lithium, and polyethylene was 1:1:1.

[0054] Under anhydrous and anaerobic conditions, alkyl metallocene hafnium was obtained by adding benzene, hafnium intermediate 1, and hafnium intermediate 2 in a 250 mL three-necked flask and reacting at 57°C for 2 h. The mass ratio of benzene, hafnium intermediate 1, and hafnium intermediate 2 was 1:1:1.

[0055] (2) Preparation of alkyl metallocene titanium

[0056] Under the protection of nitrogen, titanium intermediate 1 was obtained by stirring and dispersing titanium dichloride in a 250 mL three-necked flask, slowly adding formic acid at -10°C, and then reacting at 0°C for 2 h. The mass ratio of titanium dichloride to formic acid was 1:3.

[0057] Under the protection of nitrogen, titanium intermediate 2 was obtained by stirring and dispersing titanium dichloride in a 250 mL three-necked flask, slowly dropping methyl lithium into titanium dichloride at -25°C, bubbling hydrogen, stirring for 1 h, filtering the reaction solution, adding polyethylene with a molecular weight of 10000, slowly heating to 78°C, and reacting for 1.5 h. The mass ratio of titanium dichloride, methyl lithium, and polyethylene was 1:1:1.

[0058] Under anhydrous and anaerobic conditions, alkyl metallocene titanium was obtained by adding benzene, hafnium intermediate 1, and hafnium intermediate 2 in a 250 mL three-necked flask and reacting at 57°C for 2 h. The mass ratio of benzene, hafnium intermediate 1, and hafnium intermediate 2 was 1:1:1.

[0059] (3) Preparation of low-oxygen hafnium titanium carbon precursor

[0060] The alkyl metallocene hafnium, benzene is added into a three-necked flask, stirred to be in a suspended state, cooled to minus 12℃, the alkyl metallocene titanium is slowly added into the three-necked flask, after the dropwise addition is completed, stirring is carried out at minus 12℃ for 0.8 hours; after the temperature is increased to room temperature, the reaction is immediately stopped, and filtration is carried out under reduced pressure, to obtain a low-oxygen hafnium titanium carbon precursor. The mass ratio of the alkyl metallocene hafnium, the alkyl metallocene titanium and the benzene is 1:9:9.

[0061] The oxygen content of the low-oxygen hafnium titanium carbon precursor prepared in the embodiment is 2.25Wt%. The scanning electron microscope, TGA curve and DSC curve of the low-oxygen hafnium titanium carbon precursor 1400℃ ceramic of the embodiment are as shown in Figs. 1-3

[0062] After the low-oxygen hafnium titanium carbon precursor prepared in the embodiment is solidified, pyrolysis tests are carried out at 1400℃ and 1600℃ respectively under an argon atmosphere, and the ceramic yields at 1400℃ and 1600℃ under the condition are calculated to be 45.13% and 40.07% respectively, and the bending strengths at 900℃ and 1600℃ are 428MPa and 462MPa respectively.

[0063] Embodiment 2:

[0064] (1) Preparation of alkyl metallocene hafnium

[0065] Under the protection of nitrogen, the hafnium dichloride complex is stirred and dispersed in a 250mL three-necked flask, tetrahydrofuran is slowly added dropwise at minus 5℃, and then the temperature is increased to 50℃ for reaction for 6h, and the hafnium intermediate 1 is obtained after filtration. The mass ratio of the hafnium dichloride complex and the tetrahydrofuran is 1:34.

[0066] Under the protection of nitrogen, the hafnium dichloride complex is stirred and dispersed in a 250mL three-necked flask, methyl lithium and ethyl lithium are slowly added dropwise into the hafnium dichloride complex at minus 20℃, hydrogen is introduced, and stirring is carried out for 4h, and the reaction liquid is obtained after filtration, polypropylene with a molecular weight of 20000 is added, the temperature is slowly increased to 82℃, and reaction is carried out for 2.5h, to obtain the hafnium intermediate 2. The mass ratio of the hafnium dichloride complex, the methyl lithium and the ethyl lithium and the polypropylene is 1:40:200.

[0067] Under anhydrous and oxygen-free conditions, toluene, the hafnium intermediate 1 and the hafnium intermediate 2 are added into a 250mL three-necked flask, and reaction is carried out at 62℃ for 6h, to obtain the alkyl metallocene hafnium. The mass ratio of the toluene, the hafnium intermediate 1 and the hafnium intermediate 2 is 15:4:1.

[0068] (2) Preparation of alkyl metallocene titanium

[0069] ​Under the protection of nitrogen, dichlorobis-titanocene was stirred and dispersed in a 250 mL three-necked flask, tetrahydrofuran was slowly added dropwise at -5 ℃, then the temperature was raised to 50 ℃ for 6 h, and the titanium intermediate 1 was obtained by filtration. The mass ratio of dichlorobis-titanocene and tetrahydrofuran was 1:34.

[0070] Under the protection of nitrogen, dichlorobis-titanocene was stirred and dispersed in a 250 mL three-necked flask, tetrahydrofuran was slowly added dropwise at -5 ℃, then the temperature was raised to 50 ℃ for 6 h, and the titanium intermediate 1 was obtained by filtration. The mass ratio of dichlorobis-titanocene and tetrahydrofuran was 1:34.

[0071] Under the protection of nitrogen, dichlorobis-titanocene was stirred and dispersed in a 250 mL three-necked flask, tetrahydrofuran was slowly added dropwise at -5 ℃, then the temperature was raised to 50 ℃ for 6 h, and the titanium intermediate 1 was obtained by filtration. The mass ratio of dichlorobis-titanocene and tetrahydrofuran was 1:34.

[0072] (3) Preparation of low-oxygen hafnium titanium carbon precursor

[0073] The hafnium-based alkyl metallocene and toluene were added to a three-necked flask and stirred to a suspended state, cooled to -8 ℃, and the titanium-based alkyl metallocene was slowly added to the three-necked flask. After the addition was completed, the reaction was stopped after stirring at -8 ℃ for 1.2 h, and the low-oxygen hafnium titanium carbon precursor was obtained by filtration under reduced pressure. The mass ratio of hafnium-based alkyl metallocene, titanium-based alkyl metallocene, and benzene was 9:1:900.

[0074] The oxygen content of the low-oxygen hafnium titanium carbon precursor prepared in this example was 2.22 wt%. The low-oxygen hafnium titanium carbon precursor prepared in this example was solidified under an argon atmosphere and subjected to pyrolysis tests at 1400 ℃ and 1600 ℃, respectively, and the ceramic yields at 1400 ℃ and 1600 ℃ under the conditions were calculated to be 46.25% and 39.56%, respectively, and the bending strengths at 900 ℃ and 1600 ℃ were 430 MPa and 468 MPa, respectively.

[0075] Example 3:

[0076] (1) Preparation of hafnium-based alkyl metallocene

[0077] Under the protection of nitrogen, dichlorobis-titanocene was stirred and dispersed in a 250 mL three-necked flask, tetrahydrofuran was slowly added dropwise at -5 ℃, then the temperature was raised to 50 ℃ for 6 h, and the titanium intermediate 1 was obtained by filtration. The mass ratio of dichlorobis-titanocene and tetrahydrofuran was 1:34.

[0078] Under the protection of nitrogen, dichlorobis (tetrahydrofuran) hafnium was stirred and dispersed in a 250 mL three-necked flask, propyllithium was slowly added into dichlorobis (tetrahydrofuran) hafnium at -22 ℃, hydrogen was introduced, and the reaction was stirred for 2 h. The reaction solution was obtained by filtration, poly-1-butene with a molecular weight of 16000 was added, and the temperature was slowly increased to 80 ℃. The hafnium intermediate 2 was obtained by reacting for 2 h. The mass ratio of dichlorobis (tetrahydrofuran) hafnium, propyllithium and poly-1-butene was 1:35:180.

[0079] Under anhydrous and anaerobic conditions, dichloromethane, hafnium intermediate 1 and hafnium intermediate 2 were added into a 250 mL three-necked flask, and the reaction was carried out at 60 ℃ for 3 h to obtain alkyl hafnium. The mass ratio of toluene, hafnium intermediate 1 and hafnium intermediate 2 was 10:3:1.

[0080] (2) Preparation of alkyl hafnium

[0081] Under the protection of nitrogen, dichlorobis (tetrahydrofuran) titanium was stirred and dispersed in a 250 mL three-necked flask, acetone was slowly added at -5 ℃, and then the temperature was increased to 30 ℃. The titanium intermediate 1 was obtained by reacting for 3 h. The mass ratio of dichlorobis (tetrahydrofuran) titanium and acetone was 1:6.

[0082] Under the protection of nitrogen, dichlorobis (tetrahydrofuran) titanium was stirred and dispersed in a 250 mL three-necked flask, propyllithium was slowly added into dichlorobis (tetrahydrofuran) titanium at -20 ℃, hydrogen was introduced, and the reaction was stirred for 2 h. The reaction solution was obtained by filtration, poly-1-butene with a molecular weight of 16000 was added, and the temperature was slowly increased to 80 ℃. The titanium intermediate 2 was obtained by reacting for 2.0 h, and the solvent was recovered by further heating. The mass ratio of dichlorobis (tetrahydrofuran) titanium, propyllithium and poly-1-butene was 1:35:180.

[0083] Under anhydrous and anaerobic conditions, toluene, hafnium intermediate 1 and hafnium intermediate 2 were added into a 250 mL three-necked flask, and the reaction was carried out at 60 ℃ for 5 h to obtain alkyl hafnium. The mass ratio of toluene, hafnium intermediate 1 and hafnium intermediate 2 was 10:3:1.

[0084] (3) Preparation of low-oxygen hafnium titanium carbon precursor

[0085] Alkyl hafnium, toluene and dichloromethane were added into a three-necked flask and stirred to a suspended state. The temperature was cooled to -10 ℃, and alkyl titanium was slowly added into the three-necked flask. After the addition was completed, the reaction was stopped after stirring at -10 ℃ for 1 h. The temperature was increased to room temperature, and the low-oxygen hafnium titanium carbon precursor was obtained by filtration under reduced pressure. The mass ratio of alkyl hafnium, alkyl titanium, toluene and dichloromethane was 6:2:700.

[0086] The oxygen content of the low-oxygen hafnium titanium carbon precursor prepared in the example is 2.31 wt%. After the low-oxygen hafnium titanium carbon precursor prepared in the example is solidified, pyrolysis tests are carried out at 1400°C and 1600°C respectively under an argon atmosphere, and the ceramic yields at 1400°C and 1600°C under the condition are calculated to be 46.32% and 39.54% respectively, and the bending strengths at 900°C and 1600°C are 435 MPa and 474 MPa respectively.

[0087] The above examples are only used to illustrate the technical solutions of the present application but not to limit it, and although the present application is described in detail with reference to the best mode, those skilled in the art should understand that the technical solutions of the present application can still be modified or replaced equivalently, and these modifications or equivalent replacements should not make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. A method for preparing a low-oxygen hafnium titanium-carbon ceramic precursor, characterized in that, The preparation method includes the following steps: Step S1: Under nitrogen protection, hafnium dichlorocerocero is stirred and dispersed. Then, reagent 1 is added dropwise to hafnium dichlorocerocero at -10 to -5°C. The temperature is then raised to 0 to 50°C and reacted for 2 to 6 hours. The mixture is then filtered to obtain hafnium intermediate 1. In step S1, the mass ratio of hafnium dichloroethylene to reagent 1 is 1:3~34; Step S2: Under nitrogen protection, hafnium dichlorocerocene is stirred and dispersed. At -25~-20℃, reagent 2 is added dropwise to hafnium dichlorocerocene, and hydrogen is introduced to react for 1~4h. After filtration, a polyolefin with a molecular weight of 5500~20000 is added, and the temperature is raised to 78~82℃. The reaction is carried out for 1.5~2.5h to obtain hafnium intermediate 2. In step S2, the mass ratio of hafnium dichloroethylene, reagent 2, and polyolefin is 1:1~40:1~200; Step S3: Under anhydrous and oxygen-free conditions, the organic solvent, hafnium intermediate 1 and hafnium intermediate 2 are mixed and reacted at 57~62℃ for 2~6h to obtain alkane-based hafnium vanadate. In step S3, the mass ratio of the organic solvent, hafnium intermediate 1, and hafnium intermediate 2 is 1~15:1~4:1; Step S4: Under nitrogen protection, titanium dichlorocerocene is stirred and dispersed. Then, reagent 1 is added dropwise to titanium dichlorocerocene at -10 to -5℃. The temperature is then raised to 0 to 50℃ and reacted for 2 to 6 hours. After filtration, titanium intermediate 1 is obtained. In step S4, the mass ratio of the titanium dichlorodicyclopentadiene to reagent 1 is 1:3~34; Step S5: Under nitrogen protection, titanium dichlorodecene is stirred and dispersed. Then, reagent 2 is added dropwise to titanium dichlorodecene at -25~-20℃. Hydrogen gas is introduced and the reaction is carried out for 1~4 hours. After filtration, a polyolefin with a molecular weight of 5500~20000 is added, and the temperature is raised to 78~82℃ to obtain titanium intermediate 2. In step S5, the mass ratio of the titanium dichlorophenocene, reagent 2, and polyolefin is 1:1~40:1~200; Step S6: Under anhydrous and oxygen-free conditions, the organic solvent, titanium intermediate 1 and titanium intermediate 2 are mixed and reacted at 57~62℃ for 2~6h to obtain alkane-based titanium locene. In step S6, the mass ratio of the organic solvent, titanium intermediate 1, and titanium intermediate 2 is 1~15:1~4:1; Step S7: Mix alkane-based hafnium monoxide and organic solvent and stir until suspended. Cool to -12~-8℃, add alkane-based titanium monoxide, stir at -12~-8℃ for 0.8~1.2 hours, heat to room temperature, and then filter under reduced pressure to obtain low-oxygen hafnium titanium carbon precursor. In step S7, the mass ratio of the alkane-based hafnium vanadate, the alkane-based titanium vanadate, and the organic solvent is 1~9:9~1:9~900; In steps S1 and S4, reagent 1 is one or more of formic acid, tetrahydrofuran, acetone, chloroform, dichloromethane, chloroform, acetylacetone, n-hexane, cyclohexane, acetonitrile, N,N-dimethylformamide, N,N-dimethylacetamide, carbon tetrachloride, methanol, ethanol, isopropanol, tert-butanol, toluene, xylene, and ethylenediamine. In steps S2 and S5, reagent 2 is one or more of methyllithium, ethyllithium, propyllithium, butyllithium, vinyl magnesium bromide, n-propenyl magnesium bromide, isopropenyl magnesium bromide, n-butenyl magnesium bromide, isobutenyl magnesium bromide, n-pentenyl magnesium bromide, and isopentenyl magnesium bromide.

2. The preparation method according to claim 1, characterized in that, In step S1, the mass ratio of hafnium dichloroethylene to reagent 1 is 1:6~30; In step S4, the mass ratio of the titanium dichlorodicyclopentadiene to reagent 1 is 1:6~30.

3. The preparation method according to claim 2, characterized in that, In step S2, the mass ratio of hafnium dichlorocerocene, reagent 2, and polyolefin is 1:5~35:20~180; In step S5, the mass ratio of the titanium dichlorophenocene, reagent 2, and polyolefin is 1:5~35:20~180.

4. The preparation method according to claim 3, characterized in that, In steps S2 and S5, the molecular weight of the polyolefin is 12,000 to 16,000.

5. The preparation method according to claim 4, characterized in that, In steps S2 and S5, the polyolefin is one or more of polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, poly-1-pentene, poly-1-hexene, and poly-1-octene.

6. The preparation method according to any one of claims 1 to 5, characterized in that, In step S3, the mass ratio of the organic solvent, hafnium intermediate 1, and hafnium intermediate 2 is 5~10:2~3:1; In step S6, the mass ratio of the organic solvent, titanium intermediate 1, and titanium intermediate 2 is 5~10:2~3:1; In step S7, the mass ratio of the alkane-based hafnium vanadate, alkane-based titanium vanadate, and organic solvent is 3~6:7~2:100~700.

7. The preparation method according to claim 6, characterized in that, In steps S3, S6, and S7, the organic solvent is one or more of benzene, toluene, dichloromethane, tetrahydrofuran, anhydrous diethyl ether, DMF, anhydrous methanol, anhydrous ethanol, ethyl acetate, and N-methylpyrrolidone.

8. A low-oxygen hafnium titanium-carbon ceramic precursor, characterized in that, The low-oxygen hafnium titanium-carbon ceramic precursor is prepared using the preparation method of the low-oxygen hafnium titanium-carbon ceramic precursor according to any one of claims 1 to 7.

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