A Ti2Nb 10 O 29 Powder preparation method

Abstract

This invention provides a method for preparing titanium niobate (Ti2Nb). 10 O 29 This invention relates to a method for preparing (TiNO) powder, belonging to the field of ceramic powder preparation technology. 0.2 Nb 0.8 Using 100-micron powder as raw material, a one-step calcination method is employed. The powder is heated to 800-1300℃ in air at a heating rate of 2-10℃ / min, oxidized for 1-5 hours, and then cooled to room temperature in the furnace to obtain TNO powder. This method simplifies the preparation process and improves production efficiency. It provides a high-performance anode material for lithium-ion batteries, effectively addressing challenges in high-rate charge / discharge, high safety, and long-cycle stability.

Description

Technical Field

[0001] This invention relates to a method for preparing a lithium-ion battery anode material, and particularly to a Ti2Nb material. 10 O 29 The powder preparation method is used to improve the charging speed, enhance battery safety, and extend battery life of lithium-ion batteries. Background Technology

[0002] Lithium-ion batteries (LIBs), as a key electrochemical energy storage device, have been widely used in a wide range of fields, from portable devices to electric vehicles and power grid systems, due to their advantages such as high energy density, no memory effect, environmental friendliness, and durability. However, this technology also faces some challenges in its development, requiring improvements in charging speed, extended lifespan, and enhanced battery safety. Especially in high-performance electric vehicles and large-scale energy storage systems, high-energy-density LIBs are needed to fit within limited space and enable long-term operation of electric vehicles. These challenges have become major bottlenecks. Developing high-performance anode materials will help advance lithium-ion battery technology and broaden its application scope. Currently, graphite dominates the commercial lithium-ion battery anode material market because of its ease of lithium-ion insertion / extraction, high theoretical capacity (372 mAh / g), long cycle life, and low cost. However, its low operating potential (approximately 0.02 V vs. Li / Li) is a significant drawback. + This can lead to the formation of lithium dendrites during discharge / charge cycles, which may puncture the separator, causing internal short circuits and thermal runaway, potentially resulting in fires or even explosions, increasing safety risks. Simultaneously, the passivated solid electrolyte interface (SEI) layer on the surface of carbon materials impairs the rate capacity of LIBs during electrochemical processes, reducing coulombic efficiency. Furthermore, graphite's low ionic conductivity hinders the ultra-fast charging capability of lithium-ion batteries (its capacity is below 100 mAh / g at 2C current density). In contrast, silicon (Si), due to its abundant resources, has a theoretical capacity far exceeding that of graphite (4200 mAh / g). -1 and a suitable lithium intercalation potential (<0.5 V vs. Li / Li) +Silicon, with its relatively low cost, has attracted considerable attention and is another major commercial lithium-ion battery anode material. However, silicon undergoes significant volume expansion during electrochemical cycling, approximately 300%-400% of the original silicon particle size. This volume change makes silicon particles prone to pulverization and fragmentation during cycling, affecting the integrity of the electrode structure. Due to repeated volume expansion and contraction, the solid electrolyte interphase (SEI) film on the silicon anode is prone to rupture and reformation, leading to irreversible capacity loss and reduced battery cycle life, severely impacting the battery's charge / discharge capacity and stability. Therefore, there is an urgent need to develop novel lithium-ion battery anode materials with reasonable operating voltage, high theoretical capacity, excellent rate performance, and good safety.

[0003] Ti2Nb 10 O 29 TiO3 (TNO) is a titanium niobate with a complex structure and has attracted widespread attention as a potential anode material for fast-charging lithium-ion batteries. TNO belongs to a monoclinic Wadsley-Roth shear structure with lattice constants a = 15.57 Å, b = 3.814 Å, c = 20.54 Å, α = 90°, β = 113.7°, and γ = 90°. This crystal structure is formed by the ordered stacking of 3 × 4 × ∞ ReO3-type structural units. These structures consist of NbO6 and TiO6 octahedra with shared corners and edges, extending infinitely along the b-axis to form a columnar structure. Adjacent structural units on the same horizontal plane are connected by edge sharing. In this structure, Ti... 4+ and Nb 5+ Ions are randomly arranged at octahedral sites in a 1:5 atomic ratio, forming open tunnel-type interstitial spaces in the

[010] direction. This space allows lithium ions to insert and extract without causing structural collapse. This enables TNO to maintain good structural stability at high current densities, reduces the formation of the SEI (solid electrolyte interphase) layer, and thus improves cycle stability. Furthermore, during electrochemical reactions, TNO can pass through Nb... 5+ / Nb 4+ / Nb 3+ and Ti 4+ / Ti 3+ The multi-electron reaction of TNO provides a higher theoretical lithium storage capacity (396 mAh / g) than graphite. Notably, TNO exhibits a higher lithium-ion (de)intercalation potential (1.6 V vs. Li / Li). + This effectively prevents the formation of lithium dendrites and the decomposition of electrolytes, thereby improving battery safety and cycle stability.

[0004] In summary, Ti2Nb 10 O29 With excellent theoretical capacity, high operating voltage, and good structural stability, TiO2 has become a promising anode material for lithium-ion batteries and is being explored in greater depth. Current processes for preparing TiO2 materials include solid-state synthesis, solvothermal methods, and electrospinning. Among these, the solid-state reaction method based on TiO2 and Nb2O5 powders is used for large-scale synthesis of Ti2Nb. 10 O 29 Anode materials are the most commonly used preparation method. For example, Wu et al., in their paper "Investigation on Ti2Nb..." 10 O 29 "Ti2Nb anode material for lithium-ion batteries." TiO2 and Nb2O5 powders were mixed in a stoichiometric ratio and heated to 1100°C in air at a heating rate of 5°C / min, held at that temperature for 36 hours, and then cooled in the furnace to successfully prepare Ti2Nb. 10 O 29 The product exhibits excellent rate performance, with an initial coulombic efficiency of up to 92% at a current density of 0.1C over a potential range of 1.0 to 2.5 V. Reversible capacities of 210 mAh / g and 133 mAh / g are obtained at current densities of 2C and 10C, respectively. Additionally, Cheng et al., in their paper "Bulk Ti2Nb...",... 10 O 29 "as long-life and high-power Li-ion battery anodes." Stoichiometric TiO2 and Nb2O5 powders were mixed by high-energy ball milling and then calcined at 1000°C for 10 hours in air, followed by natural cooling to room temperature. Electrochemical results showed that the prepared Ti2Nb... 10 O 29 The material exhibits good stability during high-rate discharge-charge cycles; after 800 cycles at a current density of 10C, its reversible capacity remains at 144 mAh / g, with a capacity retention of 68%. The solid-state reaction synthesis method is very simple, but the prolonged high-temperature calcination process (above 1000°C and greater than 10 hours) leads to rapid growth of TNO grains (greater than 20 micrometers), which is detrimental to achieving excellent electrochemical performance. Liu et al., in their paper "Mesoporous Ti₂Nb 10 O 29"Ti₂Nb prepared by a solvothermal method and subsequent calcination method using interconnected nanoparticles as high-performance anode material for lithium ion batteries." 10 O 29 Microspheres. Tetraisopropyl titanium, niobium pentachloride, isopropanol, and glycerol were mixed uniformly in a specific ratio and transferred to a high-pressure reactor lined with polytetrafluoroethylene. After a solvothermal reaction at 180°C for 24 hours, the resulting product was centrifuged, washed, dried, and calcined at 900°C in air for 10 hours to obtain microspheres with a diameter of 1-2 μm assembled from TNO nanoparticles. This product exhibited excellent electrochemical performance. At different current densities (1, 5, 10, 20, and 30C), the initial discharge capacity of the TNO microspheres reached 268.9, 218.5, 205.3, 180.5, and 158.1 mAh / g, respectively; and at a current density of 10C, after 500 cycles, its capacity remained at 173.5 mAh / g, indicating excellent cycling stability. Deng et al., in their paper "One-dimensional Ti₂Nb 10 O 29 "TNO nanowires for enhanced lithium storage" were prepared using electrospinning technology. Citric acid, tetrabutyl titanate, distilled water, polyvinylpyrrolidone (PVP), and niobium oxalate were added sequentially to ethanol and thoroughly mixed. The precursor was then transferred to a disposable syringe, and a constant voltage of 12 kV was applied with a distance of 15 cm between the needle tip and the stainless steel collector. The electrospun product was heated to 800°C in air at a heating rate of 5°C / min and held for 10 hours to obtain TNO nanowires. This product exhibited excellent rate performance, with capacities of 251.3, 240.3, 221.8, 205.3, 188.1, and 174.5 at current densities of 0.5, 1, 2, 3, 4, and 5 C, respectively. The capacity was measured in mAh / g. Furthermore, after 900 cycles at 12C, the capacity remained at 85.90%, indicating excellent stability of the TNO nanowires. However, these studies show that both solvothermal and electrospinning methods require additional high-temperature calcination processes, making the synthesis routes relatively complex.

[0005] This invention addresses the shortcomings of existing lithium-ion battery anode materials in terms of high-rate charge / discharge, high safety requirements, and long-cycle stability, and proposes a novel high-performance anode material, Ti2Nb. 10 O 29Powder preparation method. Using (Ti) 0.2 Nb 0.8 Using 100-micron powder as raw material, this invention can prepare high-purity Ti2Nb through a one-step calcination method. 10 O 29 Powder. This method simplifies the preparation process and shortens the experimental cycle, making it highly suitable for lithium-ion batteries in high-performance electric vehicles and large-scale energy storage systems. It can significantly improve battery performance and safety, meeting the needs of modern high-end energy devices. Summary of the Invention

[0006] To address the limitations of existing lithium-ion battery anode materials in terms of high-rate charge / discharge, high safety requirements, and long-cycle stability, this invention proposes a novel high-performance anode material, Ti2Nb. 10 O 29 Preparation method of (TNO) powder. This method uses (Ti) 0.2 Nb 0.8 Using C powder as raw material, high-purity TNO powder was successfully prepared through a one-step calcination method. The technical route includes the following two main steps:

[0007] Ti2Nb 10 O 29 Powder preparation process: Selecting (Ti 0.2 Nb 0.8 TNO micron powder was used as raw material. This carbide precursor was first placed in a furnace and heated to 800-1300°C at a heating rate of 2-10°C / min under air atmosphere. Oxidation was then carried out at this temperature for 1-5 hours. After the oxidation reaction was complete, the furnace was cooled to room temperature to obtain high-purity TNO powder.

[0008] (Ti 0.2 Nb 0.8 Preparation of TiC micron powder: TiC, NbC, and Co powders were used as raw materials. First, TiC and NbC powders were weighed at a molar ratio of 1:4. Then, these carbide powders were weighed and mixed with Co powder at a mass ratio of 7:3. The mixed powder was pre-pressed into shape using a mold and then transferred to a furnace. Under an argon protective atmosphere, the temperature was heated to 1500℃ at a heating rate of 8℃ / min and held for 8 hours. After the reaction was completed, the product was allowed to cool naturally to room temperature with the furnace, at which point (TiC) micron powder was formed. 0.2 Nb 0.8 C / Co based composite material blocks were then prepared. The composite material blocks were subsequently immersed in a nitric acid solution to corrode and dissolve the Co alloy matrix. After corrosion, the blocks were filtered, repeatedly washed with deionized water and alcohol, and then dried to obtain (Ti)-based composite material. 0.2 Nb 0.8 )C micron powder.

[0009] The working principle of this invention is based on (Ti) 0.2 Nb 0.8 Using carbon powder as raw material, this carbide has a face-centered cubic (FCC) crystal structure (space group Fm3̅m, ID 225). In this structure, carbon atoms are located at the face centers of the cube, while Ti and Nb atoms are randomly and uniformly distributed at the vertices and body center of the cube according to a molar ratio. This crystal structure facilitates the uniform and proportional diffusion of Ti and Nb. During high-temperature oxidation, oxygen molecules rapidly penetrate into the interior of the crystal structure and react with Ti and Nb atoms to form high-purity Ti₂Nb. 10 O 29 Oxides. The Ti and Nb atoms are spaced several atoms apart in the crystal lattice, effectively reducing the required diffusion distance and accelerating their reaction with oxygen. This contrasts with the traditional solid-state synthesis of Ti₂Nb via TiO₂ and Nb₂O₅. 10 O 29 Compared with conventional methods, the method of this invention has significant advantages in terms of raw material uniformity and reaction efficiency. In conventional methods, the uneven mixing of raw materials leads to a large diffusion distance between Ti and Nb atoms, requiring higher reaction temperatures and longer holding times, and easily results in low product purity and inhomogeneity.

[0010] This invention uses (Ti) 0.2 Nb 0.8 Using Ti-Nb powder as a raw material fundamentally ensures the uniformity of the reaction environment. During oxidation, the diffusion paths required for Ti and Nb atoms are short, and these atoms can participate in the oxidation reaction in an equal and uniform manner. This characteristic effectively reduces the temperature and time required to prepare high-purity TNO powder, significantly improving the uniformity and efficiency of the reaction. The resulting TNO powder exhibits excellent electrochemical performance, meeting the stringent requirements of high-performance lithium-ion battery anode materials. Furthermore, the preparation process of this invention is simple to operate, has a short experimental cycle, and is suitable for large-scale production applications. Attached Figure Description

[0011] Figure 1 It is the Ti2Nb prepared in Example 1 10 O 29 XRD pattern of powder.

[0012] Figure 2 It is the Ti2Nb prepared in Example 1 10 O 29 SEM images of powder.

[0013] Figure 3 It is the Ti2Nb prepared in Example 1 10 O 29EDS spot analysis spectrum of powder.

[0014] Figure 4 It is the Ti2Nb prepared in Example 2 10 O 29 XRD pattern of powder.

[0015] Figure 5 It is the Ti2Nb prepared in Example 2 10 O 29 SEM images of powder.

[0016] Figure 6 It is the Ti2Nb prepared in Example 3 10 O 29 XRD pattern of powder.

[0017] Figure 7 It is the Ti2Nb prepared in Example 3 10 O 29 SEM images of powder.

[0018] Figure 8 It is the Ti2Nb prepared in Example 3 10 O 29 EDS spot analysis spectrum of powder.

[0019] Figure 9 It is the Ti2Nb prepared in Example 3 10 O 29 Raman spectra of powders.

[0020] Figure 10 It is the Ti2Nb prepared in Example 4 10 O 29 XRD pattern of powder.

[0021] Figure 11 It is the Ti2Nb prepared in Example 4 10 O 29 SEM images of powder.

[0022] Figure 12 It is the Ti2Nb prepared in Example 4 10 O 29 EDS spot analysis spectrum of powder. Detailed Implementation

[0023] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.

[0024] Example 1

[0025] In this embodiment, Ti2Nb is prepared. 10 O29 The powder production process is as follows: Select (Ti) 0.2 Nb 0.8 Micron-sized Ti2Nb powder was used as the raw material. This carbide precursor was first placed in a furnace and heated to 800°C at a heating rate of 5°C / min under air atmosphere. Oxidation was then carried out at this temperature for 2 hours. After the reaction was complete, the product was allowed to cool naturally to room temperature with the furnace, yielding high-purity Ti2Nb. 10 O 29 Powder.

[0026] The (Ti) used in this embodiment 0.2 Nb 0.8 Preparation of TiC micron powder: TiC, NbC, and Co powders were used as raw materials. First, TiC and NbC powders were weighed at a molar ratio of 1:4. Then, these carbide powders were weighed and mixed with Co powder at a mass ratio of 7:3. The mixed powder was pre-pressed into shape using a mold and then transferred to a furnace. Under an argon protective atmosphere, the temperature was heated to 1500℃ at a heating rate of 8℃ / min and held for 8 hours. After the reaction was completed, the product was allowed to cool naturally to room temperature with the furnace, at which point (TiC) micron powder was formed. 0.2 Nb 0.8 C / Co based composite material blocks were then prepared. The composite material blocks were subsequently immersed in a nitric acid solution to corrode and dissolve the Co alloy matrix. After corrosion, the blocks were filtered, repeatedly washed with deionized water and alcohol, and then dried to obtain (Ti)-based composite material. 0.2 Nb 0.8 )C micron powder.

[0027] X-ray diffraction (XRD) was performed on the prepared TNO powder. Figure 1 As shown, the obtained XRD diffraction peaks are clear and have high intensity, consistent with monoclinic Ti₂Nb. 10 O 29 The standard peaks (JCPDS 72-0159) are consistent with those of the sample. The main diffraction peaks appear at approximately 2θ 23.78°, 44.44°, and 47.65°, corresponding to the (011), (700), and (020) crystal planes, respectively, indicating good crystallinity of the sample. Furthermore, no diffraction peaks of any impurity phases were observed in the XRD pattern, confirming the prepared Ti₂Nb₂. 10 O 29 High purity of powder.

[0028] Figure 2 The prepared Ti2Nb is presented 10 O 29 The microstructure of powder. Figure 2In the SEM image shown in (a), the TNO powder exhibits a tetrahedral morphology with side lengths ranging from 4 to 7.5 micrometers. The sharp edges of these tetrahedrals indicate that the TNO powder has good dispersibility. Figure 2 (b) Further analysis revealed that these micron-sized pyramids are composed of TNO particles with diameters ranging from 100 to 250 nm. The unique pyramidal structure and fine particle size of the TNO powder contribute to increasing the specific surface area of ​​the material, providing more active sites for electrochemical applications. This optimizes its electrochemical performance, making it an ideal anode material choice for lithium-ion batteries.

[0029] Figure 3 This demonstrates the effects of preparing Ti2Nb 10 O 29 The EDS point analysis results of the powder reveal characteristic peaks for four elements: carbon (C), oxygen (O), niobium (Nb), and titanium (Ti). The analysis shows that oxygen (O) has the highest atomic percentage, reaching 56.16%, indicating a thorough oxidation process and reflecting a high oxidation state of the material. Furthermore, the molar ratio of niobium (Nb) to titanium (Ti) is 5.09:1, which is similar to Ti₂Nb. 10 O 29 The stoichiometric ratios are consistent with the phase theory; combined with the XRD pattern results, the product is confirmed to be the TNO phase. These results confirm the feasibility and correctness of the synthetic method.

[0030] Example 2

[0031] In this embodiment, Ti2Nb is prepared. 10 O 29 The powder production process is as follows: Select (Ti) 0.2 Nb 0.8 Micron-sized Ti2Nb powder was used as the raw material. This carbide precursor was first placed in a furnace and heated to 900°C at a heating rate of 5°C / min under air atmosphere. Oxidation was then carried out at this temperature for 2 hours. After the reaction was complete, the product was allowed to cool naturally to room temperature with the furnace, yielding high-purity Ti2Nb. 10 O 29 Powder. (Ti 0.2 Nb 0.8 The preparation process of the C-micron powder precursor is the same as in Example 1.

[0032] X-ray diffraction (XRD) was performed on the prepared TNO powder. Figure 4 As shown, the obtained XRD diffraction peaks are clear and have high intensity, consistent with monoclinic Ti₂Nb. 10 O 29The standard peaks (JCPDS 72-0159) are consistent with those of the sample. The main diffraction peaks appear at approximately 2θ 23.78°, 44.44°, and 47.65°, corresponding to the (011), (700), and (020) crystal planes, respectively, indicating good crystallinity of the sample. Furthermore, no diffraction peaks of any impurity phases were observed in the XRD pattern, confirming the prepared Ti₂Nb₂. 10 O 29 High purity of powder.

[0033] Figure 5 The prepared Ti2Nb is presented 10 O 29 The microstructure of powder. Figure 5 In the SEM image shown in (a), the TNO powder exhibits a tetrahedral morphology with side lengths ranging from 3 to 10 micrometers. The sharp edges of these tetrahedrals indicate that the TNO powder has good dispersibility. Figure 5 (b) Further analysis revealed that these micron-sized pyramids are composed of TNO particles with a diameter ranging from 100 to 200 nm. The unique pyramidal structure and fine particle size of the TNO powder contribute to increasing the specific surface area of ​​the material, providing more active sites for electrochemical applications. This optimizes its electrochemical performance, making it an ideal anode material choice for lithium-ion batteries.

[0034] Example 3

[0035] In this embodiment, Ti2Nb is prepared. 10 O 29 The powder production process is as follows: Select (Ti) 0.2 Nb 0.8 Micron-sized Ti2Nb powder was used as the raw material. This carbide precursor was first placed in a furnace and heated to 1000°C at a heating rate of 5°C / min under air atmosphere. Oxidation was then carried out at this temperature for 2 hours. After the reaction was complete, the product was allowed to cool naturally to room temperature with the furnace, yielding high-purity Ti2Nb. 10 O 29 Powder. (Ti 0.2 Nb 0.8 The preparation process of the C-micron powder precursor is the same as in Example 1.

[0036] X-ray diffraction (XRD) was performed on the prepared TNO powder. Figure 6 As shown, the obtained XRD diffraction peaks are clear and have high intensity, consistent with monoclinic Ti₂Nb. 10 O 29The standard peaks (JCPDS 72-0159) are consistent with those of the sample. The main diffraction peaks appear at approximately 23.78°, 24.96°, and 47.65° at 2θ, corresponding to the (011), (400), and (020) crystal planes, respectively, indicating good crystallinity of the sample. Furthermore, no diffraction peaks of any impurity phases were observed in the XRD pattern, confirming the prepared Ti₂Nb₂. 10 O 29 High purity of powder.

[0037] Figure 7 The prepared Ti2Nb is presented 10 O 29 The microstructure of powder. Figure 7 In the SEM image shown in (a), the TNO powder exhibits a tetrahedral morphology with side lengths ranging from 4 to 7 micrometers. The sharp edges of these tetrahedrals indicate that the TNO powder has good dispersibility. Figure 7 (b) Further analysis revealed that these micron-sized pyramids are composed of TNO particles with diameters ranging from 100 to 400 nm. The unique pyramidal structure and fine particle size of the TNO powder contribute to increasing the specific surface area of ​​the material, providing more active sites for electrochemical applications. This optimizes its electrochemical performance, making it an ideal anode material choice for lithium-ion batteries.

[0038] Figure 8 This demonstrates the effects of preparing Ti2Nb 10 O 29 The EDS point analysis results of the powder are shown. This spectrum reveals characteristic peaks for four elements: carbon (C), oxygen (O), niobium (Nb), and titanium (Ti). The analysis results indicate that oxygen (O) has the highest atomic percentage, reaching 60.44%. This high proportion indicates the thoroughness of the oxidation process and reflects the high oxidation state of the material. Furthermore, the molar ratio of niobium (Nb) to titanium (Ti) is 5.03:1, which is similar to Ti₂Nb. 10 O 29 The stoichiometric ratios are consistent with the phase theory; combined with the XRD pattern results, the product is confirmed to be the TNO phase. These results confirm the feasibility and correctness of the synthetic method.

[0039] Figure 9 The Raman spectrum of the prepared TNO powder is shown, and multiple characteristic peaks were detected at 112, 132, 164, 267, 348, 539, 645, 891 and 998 cm⁻¹. -1 This indicates that Ti2Nb 10 O 29 Multiple vibrational modes exist in the crystal structure. Among them, the one located at 112 cm⁻¹... -1 132 cm-1 and 164 cm -1 The characteristic peaks reflect lattice vibrations related to Nb and Ti atoms in the TNO crystal. Located at 267 cm⁻¹ -1 and 348 cm -1 The characteristic peaks indicate the symmetric and asymmetric bending vibrations of Ti-O and Nb-O bridged oxygen. Furthermore, the 539 cm⁻¹ peak... -1 and 645 cm -1 The characteristic peak indicates the metal-oxygen stretching vibration of the TiO6 octahedron, while the peak at 891 cm⁻¹ represents the metal-oxygen stretching vibration of the TiO6 octahedron. -1 and 998 cm -1 The characteristic peaks are the stretching vibrations of the Nb-O bonds in the NbO6 octahedron.

[0040] Example 4

[0041] In this embodiment, Ti2Nb is prepared. 10 O 29 The powder production process is as follows: Select (Ti) 0.2 Nb 0.8 Micron-sized Ti₂Nb powder was used as the raw material. This carbide precursor was first placed in a furnace and heated to 1200°C at a heating rate of 5°C / min under air atmosphere. Oxidation was then carried out at this temperature for 2 hours. After the reaction was complete, the product was allowed to cool naturally to room temperature with the furnace, yielding high-purity Ti₂Nb. 10 O 29 Powder. (Ti 0.2 Nb 0.8 The preparation process of the C-micron powder precursor is the same as in Example 1.

[0042] X-ray diffraction (XRD) was performed on the prepared TNO powder. Figure 10 As shown, the obtained XRD diffraction peaks are clear and have high intensity, consistent with monoclinic Ti₂Nb. 10 O 29 The standard peaks (JCPDS 72-0159) are consistent with those of the sample. The main diffraction peaks appear at approximately 23.78°, 24.96°, and 26.03° at 2θ, corresponding to the (011), (400), and (21-1) crystal planes, respectively, indicating good crystallinity of the sample. Furthermore, no diffraction peaks of any impurity phases were observed in the XRD pattern, confirming the prepared Ti₂Nb₂. 10 O 29 High purity of powder.

[0043] Figure 11 Revealing the prepared Ti2Nb 10 O 29 Powders possess unique microstructures. From Figure 11As shown in the SEM image (a), the TNO powder exhibits a square pyramidal morphology. These micron-sized pyramids have rough surfaces and irregular edges. Figure 11 (b) It was further revealed that the TNO microcones consist of closely packed columnar crystals. The length of these columnar grains ranges from approximately 1 to 3.5 micrometers.

[0044] Figure 12 This demonstrates the effects of preparing Ti2Nb 10 O 29 The EDS point analysis results of the powder reveal characteristic peaks for four elements: carbon (C), oxygen (O), niobium (Nb), and titanium (Ti). The analysis shows that oxygen (O) has the highest atomic percentage, reaching 54.27%, indicating a thorough oxidation process and reflecting a high oxidation state of the material. Furthermore, the molar ratio of niobium (Nb) to titanium (Ti) is 4.43:1, which is similar to Ti₂Nb. 10 O 29 The stoichiometric ratios are consistent with the phase theory; combined with the XRD pattern results, the product is confirmed to be the TNO phase. These results confirm the feasibility and correctness of the synthetic method.

[0045] Example 5

[0046] In this embodiment, Ti2Nb is prepared. 10 O 29 The powder production process is as follows: Select (Ti) 0.2 Nb 0.8 Micron-sized Ti2Nb powder was used as the raw material. This carbide precursor was first placed in a furnace and heated to 800°C at a heating rate of 2°C / min under air atmosphere. Oxidation was then carried out at this temperature for 5 hours. After the reaction was complete, the product was allowed to cool naturally to room temperature with the furnace, yielding high-purity Ti2Nb. 10 O 29 Powder. (Ti 0.2 Nb 0.8 The preparation process of the C-micron powder precursor is the same as in Example 1.

[0047] Example 6

[0048] In this embodiment, Ti2Nb is prepared. 10 O 29 The powder production process is as follows: Select (Ti) 0.2 Nb 0.8 Micron-sized Ti2Nb powder was used as the raw material. This carbide precursor was first placed in a furnace and heated to 1300°C at a heating rate of 10°C / min under air atmosphere, and then subjected to oxidation treatment at this temperature for 1 hour. After the reaction was complete, the product was allowed to cool naturally to room temperature with the furnace to obtain high-purity Ti2Nb. 10 O 29Powder. (Ti 0.2 Nb 0.8 The preparation process of the C-micron powder precursor is the same as in Example 1.

Claims

1. A method of producing Ti2Nb 10 O 29 powder, characterized by: Select (Ti) 0.2 Nb 0.8 )C micron powder as raw material; The product was placed in a furnace and heated to 800-1300℃ at a heating rate of 2-10℃ / min under air atmosphere, and held at this temperature for 1-5 hours for oxidation treatment. After the reaction was completed, the product was allowed to cool naturally to room temperature with the furnace to obtain Ti2Nb. 10 O 29 Powder.

2. The method according to claim 1, wherein (Ti) 0.2 Nb 0.8 The preparation steps of TiC micron powder raw material are as follows: (1) Weigh TiC and NbC powders in a molar ratio of 1:4; (2) Weigh the total carbide powder and Co powder in a mass ratio of 7:3 and mix them evenly; (3) After pre-pressing the mixed powder through a mold, transfer it to a furnace; In an argon protective atmosphere, heat the temperature to 1500℃ at a heating rate of 8℃ / min and hold for 8 hours; After the reaction is completed, let the product cool naturally to room temperature with the furnace to obtain (TiC micron powder raw material ... 0.2 Nb 0.8 (4) Immerse the composite material block in nitric acid solution to dissolve the Co alloy matrix, and obtain (Ti) after filtration, washing and drying. 0.2 Nb 0.8 )C micron powder.

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