A method for industrial production of zirconium-based composite nano metal oxide based on MOF morphology and application

Abstract

This invention discloses a method and application for the industrial-scale preparation of zirconium-based composite nano-metal oxides based on MOF morphology, belonging to the field of zirconium-based multi-component composite material preparation and its application in new energy batteries. Porous zirconium dioxide is obtained by reacting 2-aminoterephthalic acid with zirconium oxychloride followed by pyrolysis to create pores. Then, a soluble salt containing magnesium, iron, and aluminum is uniformly precipitated into the reactant to prepare a zirconium-based ternary precursor material. Finally, the product is obtained through rapid plasma sintering. This method, based on MOF morphology inheritance and multi-level structure design of composite oxides, innovatively synthesizes a novel nano-additive for lithium-ion batteries. The zirconium-based composite nano-metal oxide product prepared by this invention exhibits uniform particle morphology distribution, high sphericity, and a high specific surface area. Furthermore, when used as a cathode material additive, this zirconium-based composite nano-metal oxide can improve the electrochemical performance of ternary lithium batteries.

Description

Technical Field

[0001] This invention pertains to the preparation of zirconium-based multi-component composite materials and their application in new energy batteries. Specifically, it relates to a method and application for the industrial preparation of zirconium-based composite nano-metal oxides based on MOF morphology. Background Technology

[0002] With the rapid development of new energy vehicle power batteries towards higher energy density, ultra-fast charging, long cycle life, and high safety and stability, high-nickel ternary cathode materials have become the mainstream cathode system for high-end power batteries due to their core advantages such as high specific capacity, high compaction density, and controllable cost. However, the inherent defects of high-nickel materials face certain technical bottlenecks, mainly manifested in the following aspects: First, in the high-nickel system, a large number of nickel ions are prone to lithium / nickel cation mixing, inducing irreversible phase transitions in the layered lattice. During charging and discharging, the particles repeatedly expand and crack, resulting in rapid capacity decay. Second, high-valence nickel ions on the cathode surface catalyze the decomposition of the electrolyte, generating corrosive impurities that continuously erode the cathode surface, causing transition metal dissolution and significantly increasing the battery interface impedance. Third, under high voltage and high temperature conditions, oxygen is easily precipitated in the cathode lattice, significantly increasing the risk of battery thermal runaway. These factors will severely restrict the large-scale commercialization of high-nickel ternary batteries.

[0003] In research addressing the aforementioned issues, cathode functional additive modification has become the most mainstream and easily industrialized modification method in the industry due to its advantages of simple process, low cost, strong adaptability, and significant effects. Its core principle is to simultaneously achieve lattice structure stability, interface protection, and ion conduction optimization through the doping or surface coating of trace amounts (0.1-3 wt%) of functional components, thus solving the inherent shortcomings of high-nickel ternary materials at low cost.

[0004] Early ternary cathode additives primarily used single inert oxide coatings such as Al2O3 and TiO2, which only provided simple physical isolation and protection, but suffered from drawbacks such as ion channel blockage and poor rate performance. Second-generation fluoride and phosphate single-component additives balanced corrosion resistance and ion conductivity, but their limited functionality failed to simultaneously address multiple issues such as structural collapse, interfacial side reactions, and poor thermal stability. Currently, the industry has entered the third-generation technology stage, characterized by multi-component composites, nano-precision manufacturing, and multi-functional synergy. The core research and development direction is to construct multi-component synergistic systems to simultaneously achieve integrated modification effects such as lattice stability, interfacial corrosion resistance, rapid ion transport, and improved thermal safety.

[0005] Zirconium-based functional additives are currently a research hotspot and core material in the field of high-end power battery modification. (The text abruptly ends here, likely due to an incomplete sentence or missing information.) 4+ Ionic radius and Li +With similar molecular weight, zirconium-based composite oxides can be precisely doped into the ternary cathode lattice, effectively suppressing cation mixing and irreversible phase transitions. Simultaneously, the extremely high Zr-O bond energy provides excellent structural rigidity and thermal stability, significantly inhibiting lattice oxygen release and improving battery thermal safety. Compared to traditional single aluminum, magnesium, and titanium-based additives, zirconium-based multi-element composite oxides integrate the advantages of multiple metal components, avoiding the limitations of single-component modification, and achieving multiple benefits including structural stability, interface protection, kinetic optimization, and safety enhancement. However, traditional solid-phase mixing and co-precipitation methods for preparing zirconium-based additives suffer from problems such as uneven component dispersion, easy particle agglomeration, weak interfacial bonding, and uncontrollable functional defects, limiting their modification effects.

[0006] In view of this, the present invention provides a zirconium-based ternary composite nano-oxide prepared by an integrated process based on MOF-derived structure regulation, metal ion confined loading, and plasma rapid sintering. This process can achieve atomic-level uniform dispersion of multiple components, precise control of nanostructure, and effective regulation of defect sites, perfectly meeting the modification requirements of high-nickel ternary cathode materials and aligning with the industrial development trend of new energy batteries towards high endurance, long lifespan, and high safety. Summary of the Invention

[0007] To address the numerous problems existing in the preparation of zirconium-based multi-component composite additive materials in current technologies, this invention proposes a method for the industrial-scale preparation of zirconium-based composite nano-metal oxides based on MOF morphology. This method, based on MOF morphology inheritance and multi-level structural design of composite oxides, innovatively synthesizes a novel lithium-ion battery nano-additive. The zirconium-based composite nano-metal oxide products prepared by this invention exhibit uniform particle morphology distribution, high sphericity, and a high specific surface area. Furthermore, when used as a cathode material additive, this zirconium-based composite nano-metal oxide can improve the electrochemical performance of ternary lithium batteries.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A method for the industrial-scale preparation of zirconium-based composite nano-metal oxides based on MOF morphology is disclosed. First, zirconium MOF (UiO-66) material is prepared by reacting 2-aminoterephthalic acid with zirconium oxychloride. Then, porous zirconium dioxide is obtained through pyrolysis pore-forming treatment. Next, soluble salts containing magnesium, iron, and aluminum are uniformly precipitated into the porous zirconium dioxide to prepare a zirconium-based ternary precursor material. Finally, the zirconium-based ternary precursor material is rapidly sintered via plasma to prepare the zirconium-based composite nano-metal oxide. The detailed steps are as follows:

[0010] Step 1. Preparation of zirconium MOF (UiO-66) material:

[0011] In a reaction vessel, 2-aminoterephthalic acid and zirconium oxychloride were dissolved in N,N-dimethylformamide (DMF), and acetic acid was added as a morphology guide. The reaction was carried out at 120~200℃ for 12~36 h. After the reaction was completed, the material was washed and dried to prepare zirconium MOF (UiO-66) material.

[0012] Step 2. Preparation of porous zirconium dioxide:

[0013] In a pyrolysis apparatus, zirconium MOF (UiO-66) material is heated to 400~600℃ and maintained for 1~5 h for complete pyrolysis to prepare porous zirconium dioxide.

[0014] Step 3. Preparation of zirconium-based ternary precursor materials:

[0015] In a reaction vessel, porous zirconium dioxide is added to a soluble salt solution of magnesium, iron and aluminum ions, and the reaction is maintained at 20~25℃ for 2~4 h. After the reaction is completed, the mixture is aged for a period of time, washed and dried to prepare zirconium-based ternary precursor materials.

[0016] Step 4. Preparation of zirconium-based composite nano-metal oxides:

[0017] Zirconium-based ternary precursor materials are rapidly sintered at 1000~1500℃ in a plasma sintering apparatus to prepare zirconium-based composite nano-metal oxides.

[0018] As a preferred embodiment of the present invention, in step 1, the molar ratio between 2-aminoterephthalic acid and zirconium oxychloride is 0.5~1.5:0.5~1.5. The molar ratio between acetic acid, N,N-dimethylformamide (DMF) and zirconium oxychloride is 15~45:200~500:1.

[0019] As a preferred embodiment of the present invention, in step 2, after complete pyrolysis, the temperature is cooled to room temperature, and the heating rate and cooling rate are controlled to be 5~10 ℃ / min.

[0020] As a preferred embodiment of the present invention, in step 3, the soluble salts of magnesium, iron, and aluminum ions are chlorides, nitrates, or sulfates of the corresponding metal ions. The molar ratio of magnesium ions, iron ions, aluminum ions, and porous zirconium dioxide is 1:1:1:10~20. Before the reaction begins, the pH of the system needs to be adjusted to 4~6. The aging time after the reaction is 5~15 h. After aging, the mixture is filtered, washed with deionized water, and finally dried at 60°C for 12~36 h.

[0021] As a preferred embodiment of the present invention, in step 4, the rapid sintering time of the zirconium-based ternary precursor material in the plasma sintering equipment is less than 10 s.

[0022] This invention enables the rapid preparation of zirconium-based composite nano-metal oxides, producing products with uniform particle morphology (10-60 nm), high sphericity, and a high specific surface area (20-150 nm). 2 / g). Meanwhile, this zirconium-based composite nano-metal oxide can be used as a cathode material additive, which can significantly improve the electrochemical performance of ternary lithium batteries.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. This invention employs an integrated preparation process combining MOF-derived pore formation, multi-metal uniform precipitation, and rapid plasma sintering. Compared with traditional oxide preparation techniques such as co-precipitation, sol-gel, and solid-state sintering, it has significant technical advantages in terms of structure control, component dispersion, microstructure, and preparation efficiency.

[0025] 2. This invention utilizes the pyrolysis of UiO-66 zirconium-based MOF templates to prepare porous zirconium dioxide, achieving precise and controllable support structure. The UiO-66 material, synthesized by coordination of 2-aminoterephthalic acid and zirconium oxychloride, possesses a regular microporous framework, high specific surface area, and structural tunability. After high-temperature pyrolysis to create pores, the organic ligands completely decompose, preserving a stable hierarchical pore structure of zirconium dioxide. Compared to traditional zirconium dioxide materials, this derived porous support exhibits excellent pore connectivity and a rich number of active sites. Furthermore, the intrinsic oxygen vacancies generated by amino pyrolysis effectively enhance the material's ion conduction activity, fundamentally solving the problems of low specific surface area, insufficient activity, and disordered structure inherent in traditional supports.

[0026] 3. This invention achieves atomic-level uniform dispersion of magnesium, iron, and aluminum ternary metal components based on the confinement effect of porous zirconium dioxide channels. Traditional multi-metal composite modification processes are prone to problems such as metal component agglomeration, uneven distribution, and severe phase separation, significantly reducing the modification effect. This invention utilizes the nanopores of porous zirconium dioxide as a micro-reaction vessel, allowing soluble magnesium, iron, and aluminum metal salts to uniformly adhere to the carrier surface and internal pores through uniform sedimentation. This achieves precise and uniform loading of multi-metal components, controllable component ratios, tight interfacial bonding, and no macroscopic segregation or agglomeration, laying a theoretical and structural foundation for subsequent multifunctional synergistic modification as a cathode material.

[0027] 4. This invention significantly optimizes the microstructure and preparation efficiency of materials through a rapid plasma sintering process. Traditional high-temperature sintering suffers from drawbacks such as slow heating, long holding time, easy grain coarsening, high energy consumption, and numerous product defects. This invention employs rapid plasma sintering technology, leveraging the characteristics of extremely rapid heating, short holding time, and pulse activation, to complete precursor crystallization under low-temperature, short-time conditions. This effectively inhibits nanocrystal growth, precisely preserves the nanoscale microstructure and rich grain boundary structure, ensuring both the structural compactness and stability of the zirconium-based composite oxide and retaining excellent lithium-ion transport channels. Attached Figure Description

[0028] Figure 1 A flowchart illustrating the method for industrial-scale preparation of zirconium-based composite nanometal oxides based on MOF morphology.

[0029] Figure 2 The images shown are scanning electron microscope (SEM) images of zirconium MOF materials prepared in the examples. A, B, C, and D are SEM images of zirconium MOF materials prepared in Examples 1, 2, 3, and 4, respectively. E is a magnified view of the area within the box in D.

[0030] Figure 3 The images shown are XRD patterns of zirconium MOF materials prepared in examples 1, 2, 3, and 4. In example A, the images are XRD patterns of zirconium MOF materials prepared in examples 1, 2, 3, and 4. In example B, the images are enlarged views of the area within the box in example A.

[0031] Figure 4 The N2 isotherm adsorption curves (BET) of zirconium MOF materials prepared in the examples are shown. A, B, C, and D are the N2 isotherm adsorption curves (BET) of zirconium MOF materials prepared in Examples 1, 2, 3, and 4, respectively.

[0032] Figure 5 The images shown are scanning electron microscope (SEM) images of zirconium MOF materials prepared in examples 5, 6, 7, 8, and 9, respectively.

[0033] Figure 6 The XRD patterns of zirconium MOF materials prepared in the examples are shown below. In example A, the XRD patterns of zirconium MOF materials prepared in examples 5, 6, 7, 8, and 9 are shown below. In example B, the XRD pattern of the boxed area in example A is shown below.

[0034] Figure 7 The N2 isotherm adsorption curves (BET) of zirconium MOF materials prepared in the examples are shown. A, B, C, D, and E are the N2 isotherm adsorption curves (BET) of zirconium MOF materials prepared in Examples 5, 6, 7, 8, and 9, respectively.

[0035] Figure 8 The XRD patterns of porous zirconium dioxide materials prepared in Examples 10, 11, and 12 are shown.

[0036] Figure 9 The images shown are product photographs of porous zirconia materials prepared in examples 10, 11, and 12, respectively.

[0037] Figure 10 The images shown are scanning electron microscope (SEM) images of porous zirconia materials prepared in Examples 10, 11, and 12, respectively.

[0038] Figure 11 The XRD patterns are for the porous zirconium dioxide material prepared in Example 12 and the zirconium-based composite nano-metal oxide materials prepared in Examples 13 and 14.

[0039] Figure 12 The images shown are scanning electron microscope (SEM) images of the materials prepared in the examples. In example A, the SEM image of the porous zirconium dioxide material prepared in example 12 is shown. In example B and example C, the SEM images of the zirconium-based composite nano-metal oxide materials prepared in examples 13 and 14 are shown.

[0040] Figure 13 The following are histograms of particle size distribution of the materials prepared in the examples. In example A, the histogram of particle size distribution of the porous zirconium dioxide material prepared in example 12 is shown. In example B and example C, the histograms of particle size distribution of the zirconium-based composite nano-metal oxide materials prepared in examples 13 and 14 are shown respectively.

[0041] Figure 14 The images show scanning electron microscope (SEM) image (A), elemental mapping (B), and elemental distribution diagrams of magnesium (C), zirconium (D), iron (E), and aluminum (F) for the zirconium-based composite nano-metal oxide material prepared in Example 13.

[0042] Figure 15 XPS full spectrum of zirconium-based composite nano-metal oxide material prepared in Example 13.

[0043] Figure 16 XPS plots of C 1s (A), O 1s (B), Zr 3d (C), Fe 2p (D), Mg 1s (E), and Al 2p (F) for zirconium-based composite nano-metal oxide materials prepared in Example 13.

[0044] Figure 17 The infrared spectrum of the zirconium-based composite nano-metal oxide material prepared in Example 13 is shown.

[0045] Figure 18 The CV curves for porous zirconium dioxide materials prepared in the examples are shown below. In example A, the CV curve for porous zirconium dioxide materials prepared in Example 12 is shown below, and in example B, the CV curve for zirconium-based composite nano-metal oxide materials prepared in Example 13 is shown below.

[0046] Figure 19 The LSV diagrams are for the porous zirconium dioxide material prepared in Example 12 and the zirconium-based composite nano-metal oxide materials prepared in Examples 13 and 14.

[0047] Figure 20 The porous zirconium dioxide material prepared in Example 12 and the zirconium-based composite nano-metal oxide materials prepared in Examples 13 and 14 were tested at 10 mA / cm². 2 Overpotential histogram at location. Detailed Implementation

[0048] Please see Figure 1 As shown, this invention proposes a method for the industrial preparation of zirconium-based composite nano-metal oxides based on MOF morphology. First, zirconium MOF (UiO-66) material is prepared by reacting 2-aminoterephthalic acid with zirconium oxychloride. Then, porous zirconium dioxide is obtained by pyrolysis pore-forming treatment. Next, soluble salts containing magnesium, iron, and aluminum are uniformly precipitated in the porous zirconium dioxide to prepare zirconium-based ternary precursor material. Finally, zirconium-based composite nano-metal oxides are prepared by plasma rapid sintering of the zirconium-based ternary precursor material.

[0049] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings.

[0050] Examples 1-4: Effect of different zirconium acid molar ratios on the preparation of zirconium MOF materials

[0051] The preparation steps are as follows:

[0052] In a reaction vessel, 2-aminoterephthalic acid and zirconium oxychloride were dissolved in N,N-dimethylformamide (DMF), and acetic acid was added as a morphology guide. The reaction was carried out at 120°C for 24 h. After the reaction was completed, the material was washed and dried to prepare zirconium MOF (UiO-66) material.

[0053] In Examples 1, 2, 3, and 4, the molar ratio between 2-aminoterephthalic acid and zirconium oxychloride was 1:1, the molar ratio between N,N-dimethylformamide (DMF) and zirconium oxychloride was 200:1, and the molar ratio between acetic acid and zirconium oxychloride was 15:1, 25:1, 35:1, and 45:1, respectively.

[0054] Figure 2In the image, A, B, C, and D are scanning electron microscope (SEM) images of the zirconium MOF material prepared in Example 1 (zirconium acid molar ratio of 15:1, reaction temperature of 120 °C, and reaction time of 24 h), Example 2 (zirconium acid molar ratio of 25:1, reaction temperature of 120 °C, and reaction time of 24 h), Example 3 (zirconium acid molar ratio of 35:1, reaction temperature of 120 °C, and reaction time of 24 h), and Example 4 (zirconium acid molar ratio of 45:1, reaction temperature of 120 °C, and reaction time of 24 h), respectively. E is a magnified view of the area within the box in D.

[0055] Figure 3 In the diagram, A represents the XRD patterns of the zirconium MOF material prepared in Example 1 (zirconium acid molar ratio of 15:1, reaction temperature of 120 °C, and reaction time of 24 h), Example 2 (zirconium acid molar ratio of 25:1, reaction temperature of 120 °C, and reaction time of 24 h), Example 3 (zirconium acid molar ratio of 35:1, reaction temperature of 120 °C, and reaction time of 24 h), and Example 4 (zirconium acid molar ratio of 45:1, reaction temperature of 120 °C, and reaction time of 24 h). B is a magnified view of the area within the box in A.

[0056] Figure 4 In the table, A, B, C, and D are the N2 isothermal adsorption curves (BET) of the zirconium MOF material prepared in Example 1 (zirconium acid molar ratio of 15:1, reaction temperature of 120 °C, and reaction time of 24 h), the zirconium MOF material prepared in Example 2 (zirconium acid molar ratio of 25:1, reaction temperature of 120 °C, and reaction time of 24 h), the zirconium MOF material prepared in Example 3 (zirconium acid molar ratio of 35:1, reaction temperature of 120 °C, and reaction time of 24 h), and the zirconium MOF material prepared in Example 4 (zirconium acid molar ratio of 45:1, reaction temperature of 120 °C, and reaction time of 24 h), respectively.

[0057] pass Figure 2 , 3 As can be seen from point 4, in the preparation of zirconium MOF materials, by changing the amount of acetic acid added to control the zirconium acid molar ratio (15~45:1), it was found that the best crystal morphology and complete structure were obtained when the zirconium acid molar ratio was 45:1 (e.g., Figure 2 As shown in D and E), the XRD pattern exhibits optimal symmetry (e.g., ...). Figure 3 (As shown in A and B). The BET results show that the specific surface area is largest when the zirconium acid molar ratio is 35:1 (e.g., ...). Figure 4 (As shown). Considering the critical influence of morphology on subsequent doping and performance, a zirconium acid molar ratio of 45:1 was ultimately selected as the optimal ratio, balancing good crystallinity with potential application requirements.

[0058] Examples 5-9: Effect of different reaction temperatures on the preparation of the product—zirconium MOF material

[0059] The preparation steps are as follows:

[0060] In a reaction vessel, 2-aminoterephthalic acid and zirconium oxychloride were dissolved in N,N-dimethylformamide (DMF), and acetic acid was added as a morphology guide agent. The reaction was carried out for 24 h. After the reaction was completed, the material was washed and dried to prepare zirconium MOF (UiO-66) material.

[0061] In Examples 5, 6, 7, 8, and 9, the molar ratio of 2-aminoterephthalic acid to zirconium oxychloride was 1:1, the molar ratio of acetic acid, N,N-dimethylformamide (DMF), and zirconium oxychloride was 45:200:1, and the reaction temperatures were 120 °C, 130 °C, 140 °C, 150 °C, and 160 °C, respectively.

[0062] Figure 5 In the image, A, B, C, D, and E are scanning electron microscope (SEM) images of the zirconium MOF material prepared in Example 5 (zirconium acid molar ratio of 45:1, reaction temperature of 120 °C, and reaction time of 24 h), Example 6 (zirconium acid molar ratio of 45:1, reaction temperature of 130 °C, and reaction time of 24 h), Example 7 (zirconium acid molar ratio of 45:1, reaction temperature of 140 °C, and reaction time of 24 h), Example 8 (zirconium acid molar ratio of 45:1, reaction temperature of 150 °C, and reaction time of 24 h), and Example 9 (zirconium acid molar ratio of 45:1, reaction temperature of 160 °C, and reaction time of 24 h), respectively.

[0063] Figure 6 In the diagram, A represents the XRD patterns of the zirconium MOF material prepared in Example 5 (zirconium acid molar ratio of 45:1, reaction temperature of 120 °C, reaction time of 24 h), Example 6 (zirconium acid molar ratio of 45:1, reaction temperature of 130 °C, reaction time of 24 h), Example 7 (zirconium acid molar ratio of 45:1, reaction temperature of 140 °C, reaction time of 24 h), Example 8 (zirconium acid molar ratio of 45:1, reaction temperature of 150 °C, reaction time of 24 h), and Example 9 (zirconium acid molar ratio of 45:1, reaction temperature of 160 °C, reaction time of 24 h). B is a magnified view of the area within the box in A.

[0064] Figure 7In the table, A, B, C, D, and E are the N2 isothermal adsorption curves (BET) of the zirconium MOF material prepared in Example 5 (zirconium acid molar ratio of 45:1, 120 °C, 24 h), Example 6 (zirconium acid molar ratio of 45:1, 130 °C, 24 h), Example 7 (zirconium acid molar ratio of 45:1, 140 °C, 24 h), Example 8 (zirconium acid molar ratio of 45:1, 150 °C, 24 h), and Example 9 (zirconium acid molar ratio of 45:1, 160 °C, 24 h), respectively.

[0065] pass Figure 5 , 6 As can be seen from point 7, under the condition that the molar ratio of zirconium acid is determined to be 45:1, by controlling the reaction temperature (120~160℃), it was found that the crystal morphology and structure obtained at the reaction temperature of 150℃ are better (e.g., Figure 5 As shown), the XRD diffraction peaks are good (e.g. Figure 6 As shown), the largest specific surface area (e.g.) Figure 7 (As shown). Based on a comprehensive consideration of morphology, crystal quality, and specific surface area, 150℃ was determined to be the optimal synthesis temperature.

[0066] Examples 10-12: Effects of different pyrolysis temperatures on the prepared product – porous zirconium dioxide material

[0067] The preparation steps are as follows:

[0068] 1. In a reaction vessel, 2-aminoterephthalic acid and zirconium oxychloride were dissolved in N,N-dimethylformamide (DMF), and acetic acid was added as a morphology guide. The reaction was carried out at 150 °C for 24 h. After the reaction, the mixture was washed and dried to prepare zirconium MOF (UiO-66) material. The molar ratio of 2-aminoterephthalic acid to zirconium oxychloride was 1:1, and the molar ratio of acetic acid, N,N-dimethylformamide (DMF), and zirconium oxychloride was 45:200:1.

[0069] 2. In a pyrolysis apparatus, the zirconium MOF (UiO-66) material was heated and maintained for 2 h for pyrolysis to prepare porous zirconium dioxide; in Examples 10, 11 and 12, the pyrolysis maintenance temperatures were 400 ℃, 500 ℃ and 600 ℃, respectively, and the heating rate and cooling rate were both controlled at 5 ℃ / min.

[0070] Figure 8XRD patterns of porous zirconium dioxide materials prepared in Example 10 (pyrolysis temperature 400 °C, pyrolysis time 2 h), Example 11 (pyrolysis temperature 500 °C, pyrolysis time 2 h), and Example 12 (pyrolysis temperature 600 °C, pyrolysis time 2 h).

[0071] Figure 9 In the image, A, B, and C are product photographs of porous zirconium dioxide material prepared in Example 10 (pyrolysis temperature 400 ℃, pyrolysis time 2 h), porous zirconium dioxide material prepared in Example 11 (pyrolysis temperature 500 ℃, pyrolysis time 2 h), and porous zirconium dioxide material prepared in Example 12 (pyrolysis temperature 600 ℃, pyrolysis time 2 h), respectively.

[0072] Figure 10 In the image, A, B, and C are scanning electron microscope (SEM) images of the porous zirconium dioxide material prepared in Example 10 (pyrolysis temperature 400 °C, pyrolysis time 2 h), Example 11 (pyrolysis temperature 500 °C, pyrolysis time 2 h), and Example 12 (pyrolysis temperature 600 °C, pyrolysis time 2 h), respectively.

[0073] pass Figure 8 , 9 As can be seen from 10, during the pyrolysis of zirconium MOF materials, the XRD peaks become sharper and the crystallinity increases with increasing temperature (e.g., ...). Figure 8 As shown); the product at 400~500℃ is gray due to residual carbon, and the particles are severely agglomerated; at 600℃, the powder is pure white (as shown). Figure 9 As shown), the particle size is uniform and the dispersibility is good (e.g. Figure 10 (As shown). Considering both crystal quality and dispersibility, 600℃ was determined to be the optimal pyrolysis temperature.

[0074] Examples 13-14: Effects of different ratios on the prepared product – zirconium-based composite nanomaterials

[0075] The preparation steps are as follows:

[0076] 1. In a reaction vessel, 2-aminoterephthalic acid and zirconium oxychloride were dissolved in N,N-dimethylformamide (DMF), and acetic acid was added as a morphology guide. The reaction was carried out at 150 °C for 24 h. After the reaction, the mixture was washed and dried to prepare zirconium MOF (UiO-66) material. The molar ratio of 2-aminoterephthalic acid to zirconium oxychloride was 1:1, and the molar ratio of acetic acid, N,N-dimethylformamide (DMF), and zirconium oxychloride was 45:200:1.

[0077] 2. In a pyrolysis apparatus, zirconium MOF (UiO-66) material was heated to 600℃ and maintained for 2 h for pyrolysis to prepare porous zirconium dioxide; the heating rate and cooling rate were both controlled at 5 ℃ / min.

[0078] 3. In a reaction vessel, porous zirconium dioxide was added to a soluble salt solution of magnesium, iron, and aluminum ions, and the reaction was maintained at 24°C for 2 h. The pH of the system needed to be adjusted to 6 before the reaction started. After the reaction, the mixture was aged for 12 h, washed (using deionized water), and dried at 60°C for 24 h to prepare the zirconium-based ternary precursor material. The soluble salts of magnesium, iron, and aluminum ions mentioned in Examples 13 and 14 were all chlorides, and the molar ratios between magnesium chloride, iron sulfide, aluminum trichloride, and porous zirconium dioxide were 1:1:1:10 and 1:1:1:20, respectively.

[0079] 4. In a plasma sintering apparatus, zirconium-based ternary precursor materials are rapidly sintered at 1200℃ (less than 10 s) to prepare zirconium-based composite nano-metal oxides.

[0080] Figure 11 XRD patterns of porous zirconium dioxide material prepared in Example 12, zirconium-based composite nano-metal oxide material prepared in Example 13 (molar ratio of magnesium, iron, aluminum, zirconium is 1:1:1:10), and zirconium-based composite nano-metal oxide material prepared in Example 14 (molar ratio of magnesium, iron, aluminum, zirconium is 1:1:1:20).

[0081] Figure 12 In the image, A, B, and C are scanning electron microscope (SEM) images of porous zirconium dioxide material prepared in Example 12, zirconium-based composite nano-metal oxide material prepared in Example 13 (with a molar ratio of magnesium, iron, aluminum, and zirconium of 1:1:1:10), and zirconium-based composite nano-metal oxide material prepared in Example 14 (with a molar ratio of magnesium, iron, aluminum, and zirconium of 1:1:1:20), respectively.

[0082] Figure 13 In the figure, A, B, and C are the particle size histograms of the porous zirconium dioxide material prepared in Example 12, the zirconium-based composite nano-metal oxide material prepared in Example 13 (with a molar ratio of magnesium, iron, aluminum, and zirconium of 1:1:1:10), and the zirconium-based composite nano-metal oxide material prepared in Example 14 (with a molar ratio of magnesium, iron, aluminum, and zirconium of 1:1:1:20), respectively.

[0083] Figure 14 In the diagram, A, B, C, D, E, and F are scanning electron microscope images, elemental surface scanning (MAPPING) analysis diagrams, and elemental distribution diagrams of magnesium, zirconium, iron, and aluminum, respectively, for the zirconium-based composite nano-metal oxide material prepared in Example 13.

[0084] Figure 15XPS full spectrum of zirconium-based composite nano-metal oxide material prepared in Example 13.

[0085] Figure 16 In the figure, A, B, C, D, E, and F are the XPS plots corresponding to C 1s, O 1s, Zr 3d, Fe 2p, Mg 1s, and Al 2p, respectively.

[0086] Figure 17 The infrared spectrum of the zirconium-based composite nano-metal oxide material prepared in Example 13 is shown.

[0087] Figure 18 In the figure, A is the CV curve of the porous zirconium dioxide material prepared in Example 12, and B is the CV curve of the zirconium-based composite nano-metal oxide material prepared in Example 13.

[0088] Figure 19 The LSV plots are for the porous zirconium dioxide material prepared in Example 12, the zirconium-based composite nano-metal oxide material prepared in Example 13 (with a molar ratio of magnesium, iron, aluminum, and zirconium of 1:1:1:10), and the zirconium-based composite nano-metal oxide material prepared in Example 14 (with a molar ratio of magnesium, iron, aluminum, and zirconium of 1:1:1:20).

[0089] Figure 20 For Example 12, porous zirconium dioxide material was prepared; for Example 13, zirconium-based composite nano-metal oxide material was prepared (magnesium, iron, aluminum, zirconium molar ratio of 1:1:1:10); and for Example 14, zirconium-based composite nano-metal oxide material was prepared (magnesium, iron, aluminum, zirconium molar ratio of 1:1:1:20) at 10 mA / cm 2 Overpotential histogram at location.

[0090] As the doping ratio increases (the molar ratio of magnesium, iron, aluminum, and zirconium increases from 1:1:1:10 to 1:1:1:20), the intensity of the XRD diffraction peak gradually decreases compared to undoped zirconium oxide (e.g., ...). Figure 11 As shown in the figure). SEM analysis shows that the original grain size of undoped zirconium oxide is 59.39 nm; after doping, the grain size increases with increasing doping ratio, decreasing to 56.6 nm and 44.36 nm respectively (as shown in the figure). Figure 12 , Figure 13 As shown). Elemental mapping confirmed the uniform doping of magnesium, iron, and aluminum in the 1:1:1:10 sample (as shown). Figure 14 (As shown).

[0091] XPS results showed that Al 2p (74.5 eV), Mg 2p and Fe 2p 3 / 2 (711.85 eV) with Fe 2p 1 / 2 The characteristic peaks of (724.96 eV) correspond to Al 3+ Mg2+ and Fe 3+ The oxidation state of Zr. Compared with pure tetragonal zirconium oxide, the 3d binding energy of Zr shifts after doping, and the proportion of the peak area corresponding to oxygen vacancies in the O 1s spectrum increases significantly, proving that the three ions have successfully substituted Zr. 4+ Entering the crystal lattice to achieve ternary doping (such as...) Figure 15 , 16 (As shown). Infrared spectroscopy shows that the Zr-O stretching vibration peak of pure tetragonal zirconia is located at 460–470 cm⁻¹. -1 After doping, the peak shifted to a higher wavenumber, reaching 515.99 cm⁻¹. -1 (Blue shift), which stems from the contributions of Mg-O, Fe-O, and Al-O bonds, can serve as evidence of successful magnesium, iron, and aluminum doping (e.g. Figure 17 (As shown).

[0092] According to the electrochemical test results, the doping ratio of 1:1:1:10 resulted in the lowest overpotential (295 mV), significantly lower than that of undoped (469 mV) and 1:1:1:20 (381 mV), demonstrating optimal electrochemical reversibility. Therefore, a doping ratio of magnesium, iron, aluminum, and zirconium molar ratio of 1:1:1:10 is the optimal choice (e.g., ...). Figure 18 , 19 (As shown in Figure 20).

[0093] Example 15: Application of zirconium-based composite nano-metal oxides in ternary lithium batteries

[0094] Ternary lithium battery cathode materials were prepared according to existing methods, and lithium-ion batteries were assembled and their electrochemical performance was tested. The main raw material for the ternary lithium battery cathode material was a nickel-cobalt-manganese precursor, the lithium source was lithium carbonate, and the additives were commercially available zirconium dioxide, the porous zirconium dioxide material prepared in Example 12, and the zirconium-based composite nano-metal oxide material prepared in Example 13, with each additive ratio being 2 wt%.

[0095] Table 1 Comparison of Electrochemical Performance Tests

[0096] Additive selection <![CDATA[Initial discharge specific capacity (0.5C) (mAh·g -1 )]]> <![CDATA[Discharge specific capacity (0.5C) (mAh·g after 120 cycles -1 )]]> Capacity retention rate (%) No additives 160 120 75 Commercially available zirconium dioxide 200 160 80 Example 12: Preparation of porous zirconium dioxide material 215 185 86.4 Zirconium-based composite nano-metal oxides prepared in Example 13 220 200 90.9

[0097] As shown in Table 1, the comparison reveals that, compared to traditional zirconium dioxide additives, the zirconium-based composite nano-metal oxides prepared in this invention, when applied in ternary lithium batteries, function effectively through doping or surface coating, with performance improvements mainly manifested in the following aspects:

[0098] 1. The zirconium-based composite nano-metal oxide prepared by this invention combines the high structural stability and high thermal safety of zirconium-based materials with the synergistic modification advantages of magnesium, iron and aluminum multi-components. It can accurately match the modification requirements of high-nickel ternary cathode materials and is a multifunctional cathode additive suitable for high-end power batteries with broad application prospects.

[0099] 2. The zirconium-based composite nano-metal oxide prepared by this invention, as a composite additive for cathode materials, can comprehensively address the core shortcomings of high-nickel ternary materials. On the one hand, the zirconium ion radius in the system is highly similar to that of lithium ions, allowing it to be moderately doped into the ternary cathode lattice, effectively suppressing lithium-nickel cation mixing during charging and discharging, alleviating irreversible phase transitions in the layered lattice, inhibiting cathode particle cracking and pulverization, and significantly improving battery cycle life. On the other hand, the high-bond-energy zirconium-oxygen framework can significantly improve the thermal stability of the cathode material, suppress lattice oxygen evolution under high temperature and overcharge conditions, reduce the risk of battery thermal runaway, and improve the safety performance of power batteries. Simultaneously, the synergistic effect of the magnesium, iron, and aluminum multi-metal components can form a dense and highly ionicly conductive passivation protective layer on the cathode surface, effectively neutralizing HF corrosion impurities in the electrolyte, inhibiting electrolyte decomposition and transition metal dissolution, reducing battery interface impedance, and optimizing battery rate performance and low-temperature charge-discharge performance. This solves the problem of single alumina and zirconium oxide additives having limited functionality and modification effects.

Claims

1. A method for the industrial-scale preparation of zirconium-based composite nano-metal oxides based on MOF morphology, characterized in that, First, zirconium MOF (UiO-66) material was prepared by reacting 2-aminoterephthalic acid with zirconium oxychloride. Then, porous zirconium dioxide was obtained by pyrolysis pore-forming treatment. Next, soluble salts containing magnesium, iron, and aluminum were uniformly precipitated in the porous zirconium dioxide to prepare zirconium-based ternary precursor material. Finally, zirconium-based composite nano-metal oxide was prepared by plasma rapid sintering of the zirconium-based ternary precursor material.

2. The method as described in claim 1, characterized in that, The specific steps are as follows: Step 1. Preparation of zirconium MOF (UiO-66) material: In a reaction vessel, 2-aminoterephthalic acid and zirconium oxychloride were dissolved in N,N-dimethylformamide (DMF), and acetic acid was added as a morphology guide. The reaction was carried out at 120~200℃ for 12~36 h. After the reaction was completed, the material was washed and dried to prepare zirconium MOF (UiO-66) material. Step 2. Preparation of porous zirconium dioxide: In a pyrolysis apparatus, zirconium MOF (UiO-66) material is heated to 400~600℃ and maintained for 1~5 h for complete pyrolysis to prepare porous zirconium dioxide. Step 3. Preparation of zirconium-based ternary precursor materials: In a reaction vessel, porous zirconium dioxide is added to a soluble salt solution of magnesium, iron and aluminum ions, and the reaction is maintained at 20~25℃ for 2~4 h. After the reaction is completed, the mixture is aged for a period of time, washed and dried to prepare zirconium-based ternary precursor materials. Step 4. Preparation of zirconium-based composite nano-metal oxides: Zirconium-based ternary precursor materials are rapidly sintered at 1000~1500℃ in a plasma sintering apparatus to prepare zirconium-based composite nano-metal oxides.

3. The method as described in claim 2, characterized in that, In step 1, the molar ratio between 2-aminoterephthalic acid and zirconium oxychloride is 0.5~1.5:0.5~1.

5.

4. The method as described in claim 2, characterized in that, In step 1, the molar ratio of acetic acid, N,N-dimethylformamide (DMF) and zirconium oxychloride is 15~45:200~500:

1.

5. The method as described in claim 2, characterized in that, In step 2, after complete pyrolysis, the temperature is reduced to room temperature, and the heating rate and cooling rate are controlled at 5~10 ℃ / min.

6. The method as described in claim 2, characterized in that, In step 3, the soluble salts of magnesium, iron, and aluminum ions are chlorides, nitrates, or sulfates of the corresponding metal ions. The molar ratio between magnesium ions, iron ions, aluminum ions, and porous zirconium dioxide is 1:1:1:10~20. The pH of the system needs to be adjusted to 4~6 before the reaction begins.

7. The method as described in claim 2, characterized in that, In step 3, the aging time after reaction is 5-15 h. After aging, the mixture is filtered, washed with deionized water, and finally dried at 60°C for 12-36 h.

8. The method as described in claim 2, characterized in that, In step 4, the zirconium-based ternary precursor material undergoes rapid sintering in a plasma sintering apparatus for less than 10 seconds.

9. The zirconium-based composite nano-metal oxide prepared by the method according to any one of claims 1 to 8, characterized in that, Its microscopic size is 10~60 nm, and its specific surface area is 20~150 m². 2 / g.

10. The application of the zirconium-based composite nano-metal oxide as described in claim 9 as an additive for the cathode material of ternary lithium batteries.

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