High specific surface area high activity metal hydroxide, and preparation method and application thereof

Abstract

This application provides a high specific surface area and highly active metal hydroxide, its preparation method, and its application, belonging to the field of new energy material preparation technology. The method includes: dissolving a binary or ternary metal source in deionized water at room temperature and magnetically stirring to form a clear metal salt solution; sequentially adding ammonium fluoride, hexamethylenetetramine, and a surfactant selectively added for the binary or ternary metal source, mixing thoroughly to obtain a precursor solution; heating the precursor solution using a two-stage heating mode of low-temperature induced nucleation and medium-temperature directional growth; after the reaction system naturally cools to room temperature, collecting the precipitate, washing and drying it to obtain the target metal hydroxide; and obtaining target metal hydroxides with different structures by controlling the molar ratio of metal ions within the binary or ternary metal source. This method offers a simple and controllable preparation process, is adaptable to binary-ternary systems, and is green and economical.

Description

Technical Field

[0001] This application relates to the field of new energy material preparation technology, and in particular to a high specific surface area and highly active metal hydroxide, its preparation method and application. Background Technology

[0002] In new energy devices, the microstructure (such as morphology, pore size, and wall thickness) and surface properties (such as active site exposure rate) of electrode materials are the core factors determining device capacity, rate performance, and cycle stability. Metal hydroxides, due to their abundant redox active sites and good electrochemical reversibility, have become a research hotspot for next-generation electrode materials. However, existing multi-component metal hydroxide preparation technologies suffer from the following unavoidable technical bottlenecks, severely restricting their industrial application.

[0003] 1. Poor controllability of morphology and structure, resulting in low mass transfer efficiency: Existing preparation methods (such as co-precipitation and conventional isothermal hydrothermal methods) struggle to achieve synergistic control of hierarchical structure and specific morphology: zinc cobalt hydroxides prepared by traditional co-precipitation methods have low specific surface areas and insufficient exposure of electrochemical active sites; even with hydrothermal methods, relying solely on a single additive or isothermal reaction (as in the reported zinc cobalt hydroxide preparation process) easily leads to disordered nanosheet stacking (specific surface area of ​​only 150 m²). 2 The uneven wall thickness of the hollow structure (wall thickness > 30 nm) or the uneven wall thickness of the hollow structure result in a long ion diffusion path and low mass transfer efficiency, which cannot meet the requirements of high-rate devices.

[0004] 2. Poor adaptability of diversified systems and high cost of scaling up: Existing technologies are mostly developed for single binary systems (such as zinc-cobalt and manganese-cobalt), and it is difficult to extend them to ternary systems (such as zinc-cobalt-manganese). Moreover, the preparation of ternary metal hydroxides often relies on expensive template agents (such as carbon spheres and polymer microspheres) or multi-step processes (such as synthesizing precursors first and then calcining), which not only leads to poor structural repeatability (batch difference > 10%), but also increases raw material costs by 30-50%, which cannot meet the economic requirements of large-scale production.

[0005] 3. There is an inherent contradiction between performance and process: To improve the specific surface area and activity of materials, existing technologies require the introduction of high-temperature calcination (>200℃) or complex surface modifications (such as carbon coating). However, high temperatures can easily damage the material's hierarchical structure, while complex modifications increase the number of process steps. For example, in existing publicly available technologies, manganese cobalt hydroxide, after calcination at 250℃, has a capacity retention rate of less than 70% after 500 cycles, and the increased process complexity leads to a decrease in production efficiency of more than 40%.

[0006] Therefore, developing a template-free, template-compatible, and precisely controllable preparation method for various morphologies is key to breaking through existing technological bottlenecks and promoting the large-scale application of metal hydroxides in the new energy field. Summary of the Invention

[0007] In view of this, embodiments of this application provide a high specific surface area, highly active metal hydroxide, its preparation method, and its application, at least partially solving the problems of "difficult morphology control, small specific surface area, poor compatibility of multi-component systems, and complex processes" in the preparation of binary or ternary metal hydroxides in the prior art. Through the innovative design of a combined process of "synergistic additives (ammonium fluoride + hexamethylenetetramine + system-specific surfactant) and step-temperature controlled hydrothermal treatment," the following objectives are achieved: (1) Precisely prepare various high specific surface area integral-level structures (flower-like, hollow spherical needle clusters, sea urchin-like ternary hollow, thin-walled hollow), and control the specific surface area to 50-400 m². 2 / g, increasing the exposure rate of electrochemical active sites to >80%; (2) Ensure that the prepared materials have high capacity (specific capacity of battery ≥250 mAh / g, specific capacitance of supercapacitor ≥1600 F / g), high rate performance and long cycle stability (retention rate >85% after 5000 cycles) in new energy devices. (3) The template-free one-step hydrothermal method is adopted, which simplifies the process steps (only 3 core operations), reduces raw material costs (no expensive template agent is required), and is suitable for large-scale industrial production (process repeatability > 95%).

[0008] In a first aspect, embodiments of this application provide a method for preparing a high specific surface area, highly active metal hydroxide, comprising: Precursor solution preparation: At room temperature, a binary or ternary metal source is dissolved in deionized water and magnetically stirred to form a clear metal salt solution; ammonium fluoride, hexamethylenetetramine, and a surfactant selectively added for the binary or ternary metal source are added sequentially to the metal salt solution and magnetically stirred until uniformly mixed to obtain the precursor solution; Stepped temperature-controlled hydrothermal reaction: The precursor solution is heated in a two-stage temperature-controlled mode of low-temperature induced nucleation and medium-temperature directional growth. The temperature of the low-temperature induced nucleation stage is controlled at 10-40℃ and the reaction is kept at a constant temperature for 0.5-2 hours; the temperature of the medium-temperature directional growth stage is controlled at 60-100℃ and the reaction is kept at a constant temperature for 4-12 hours. Post-processing: After the reaction system is naturally cooled to room temperature, the precipitate is collected, washed, and dried to obtain the target metal hydroxide; Among them, by adjusting the molar ratio of various metal ions in a binary or ternary metal source, target metal hydroxides with different structures can be obtained.

[0009] According to a specific implementation of the embodiments of this application, the binary metal source includes, but is not limited to, a combination of zinc and cobalt sources, a combination of zinc and manganese sources, or a combination of manganese and cobalt sources; the ternary metal source includes, but is not limited to, a combination of zinc, cobalt, and manganese sources; the zinc source is selected from zinc nitrate, zinc chloride, or zinc sulfate; the cobalt source is selected from cobalt nitrate, cobalt chloride, or cobalt sulfate; and the manganese source is selected from manganese nitrate, manganese chloride, or manganese sulfate.

[0010] According to a specific implementation of an embodiment of this application, obtaining target metal hydroxides with different structures by adjusting the molar ratio of various metal ions in a binary or ternary metal source includes: When the molar ratio of zinc ions to cobalt ions in the combination of zinc and cobalt sources is adjusted to 1:1-3:1, a flower-like hierarchical zinc-cobalt hydroxide is obtained. When the molar ratio of zinc ions to manganese ions in the combination of zinc and manganese sources is adjusted to 1:1-3:2, hollow spherical needle-shaped zinc-manganese hydroxide is obtained. By adjusting the molar ratio of manganese ions to cobalt ions in the combination of manganese and cobalt sources to 0.3:0.7-0.7:0.3, thin-walled hollow nanospheres of manganese-cobalt bimetallic hydroxide were obtained. By adjusting the molar ratio of zinc ions, cobalt ions, and manganese ions in the combination of zinc, cobalt, and manganese sources to (1-3):(1-3):(1-3), urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres were obtained.

[0011] According to a specific implementation of the embodiments of this application, when the target metal hydroxide is a flower-shaped zinc-cobalt hydroxide or a hollow spherical needle-shaped zinc-manganese hydroxide, the stepped temperature-controlled hydrothermal reaction adopts a water bath environment, the temperature of the low-temperature induced nucleation stage is 25-30℃, and the temperature of the medium-temperature directional growth stage is 80-90℃. When the target metal hydroxide is a sea urchin-shaped zinc-cobalt-manganese ternary hollow nanosphere or a manganese-cobalt bimetallic hydroxide thin-walled hollow nanosphere, the stepped temperature-controlled hydrothermal reaction adopts a hydrothermal reactor or oil bath environment, the temperature of the low-temperature induced nucleation stage is 20-35℃, and the temperature of the medium-temperature directional growth stage is 85-95℃.

[0012] According to a specific implementation of the embodiments of this application, the total concentration of metal ions in the metal salt solution is 0.05-3 mol / L, the molar ratio of ammonium fluoride to the total metal ions is 0.5:1-2:1, and the molar ratio of hexamethylenetetramine to the total metal ions is 1:1-3:1.

[0013] According to a specific implementation of the embodiments of this application, the surfactant selectively added to the ternary metal source is polyvinylpyrrolidone, and the mass ratio of polyvinylpyrrolidone to the total metal ions is 0.01:1-0.05:1; the surfactant selectively added to the binary metal source is hexadecyltrimethylammonium bromide or sodium dodecyl sulfate, and the concentration of hexadecyltrimethylammonium bromide or sodium dodecyl sulfate is 0.01-0.1 mol / L.

[0014] According to a specific implementation of an embodiment of this application, the collection of precipitates, and the washing and drying of the precipitates, includes: Collect the precipitate by centrifugation or filtration. The centrifugation speed is 3000-12000 rpm and the centrifugation time is 5-15 minutes. Wash the precipitate 3-5 times alternately with deionized water and anhydrous ethanol until the pH of the washing solution is 6.5-7.5; The washed product is placed in a vacuum oven for drying at a temperature of 60-100℃ for 10-30 hours.

[0015] According to a specific implementation of the embodiments of this application, if the target metal hydroxide is a flower-like hierarchical zinc-cobalt hydroxide or a hollow spherical needle-like zinc-manganese hydroxide, the centrifugation speed is 3000-8000 rpm, the drying temperature is 80-90℃, and the drying time is 15-20 hours. If the target metal hydroxide is a sea urchin-shaped zinc-cobalt-manganese ternary hollow nanosphere or a manganese-cobalt bimetallic hydroxide thin-walled hollow nanosphere, the centrifugation speed is 8000-12000 rpm, the drying temperature is 60-80℃, and the drying time is 20-24 hours.

[0016] Secondly, embodiments of this application also provide a high specific surface area and high activity metal hydroxide, prepared by the preparation method described in any embodiment of the first aspect, wherein the high specific surface area and high activity metal hydroxide is any one of the following: Flower-like hierarchical zinc-cobalt hydroxide: It has a three-dimensional flower-like structure, composed of interlaced polygonal nanosheets with side lengths of 80-120 nm and diameters of 2-3 μm, with a specific surface area of ​​50-200 m². 2 / g; Hollow spherical needle cluster type zinc manganese hydroxide: It is a structure with needle-like protrusions with a length of 50-100 nm growing on the surface of a hollow substrate, and the diameter of the hollow substrate is 1-2 μm; Manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres: These are thin-walled spherical shells with velvety secondary structures, ranging in diameter from 100 to 500 nm, wall thickness from 5 to 20 nm, and specific surface area from 200 to 300 m². 2 / g; Ulcer-like zinc-cobalt-manganese ternary hollow nanospheres: These are structures with needle-like spikes growing on the hollow sphere walls for 20-100 nm in length, a sphere diameter of 100-500 nm, a hollow portion diameter of 50-300 nm, a wall thickness of 10-30 nm, and a specific surface area of ​​250-400 m². 2 / g.

[0017] Thirdly, embodiments of this application provide an application of high specific surface area and high activity metal hydroxide as described in the second aspect, using flower-like hierarchical zinc-cobalt hydroxide, urchin-like zinc-cobalt-manganese ternary hollow nanospheres, or manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres to prepare the positive electrode of a zinc-ion battery; Alternatively, a catalytic layer for zinc-air batteries can be prepared using hollow spherical needle-shaped zinc-manganese hydroxide. Alternatively, manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres or urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres can be used to prepare electrode active materials for supercapacitors. Alternatively, urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres can be used to prepare the negative electrode for lithium-ion batteries.

[0018] Beneficial effects: The high specific surface area and high activity metal hydroxides, their preparation methods, and applications in this application have advantages in three dimensions: structural innovation, process breakthrough, and improved economic efficiency, and each advantage is supported by clear data: (1) Structural and performance innovation: to resolve the contradiction between mass transfer efficiency and stability.

[0019] Through the coupling effect of "synergistic additives + step temperature control", precise regulation of microstructure is achieved: Specific surface area is significantly increased: reaching 50-400 m² 2 / g, compared to traditional coprecipitation methods (≤50m) 2 / g) is increased by 2-5 times, compared with the conventional hydrothermal method (≤150m) 2 / g) increased by 1.5-2.5 times; High active site exposure rate: >80%, more than double that of existing technologies (<40%); Excellent electrochemical performance: battery specific capacity 250-500mAh / g (@1A / g), supercapacitor specific capacitance 1600-3000F / g (@5mV / s), retention rate >85% after 5000 cycles, which is more than 10 times more stable than the manganese cobalt hydroxide in the existing publicly available technology (retention rate <70% after 500 cycles).

[0020] (2) Process versatility and controllability: It is adaptable to diverse systems and does not require complex equipment.

[0021] Wide system adaptability: It can cover the entire binary (zinc-cobalt, zinc-manganese, manganese-cobalt) and ternary (zinc-cobalt-manganese) system without the need to develop new processes for a single system; Template-free and conventional equipment: No expensive template agents are required (reducing raw material costs by 30%-50%), and conventional water bath / oil bath / hydrothermal reactor equipment is used, eliminating the need for high-temperature and high-pressure devices (reducing equipment investment by 40%). High process repeatability: Through precise parameter control, the structural difference between batches is <5%, and the repeatability is >95%, meeting the needs of large-scale production.

[0022] (3) Green economy: It meets the requirements of industrialization in terms of environmental protection and cost.

[0023] Green and environmentally friendly: The preparation process produces no toxic or harmful substances (such as no fluoride-containing wastewater or organic waste liquid), and the post-treatment washing liquid can be recycled (reducing wastewater discharge by 60%). Low cost: The raw materials are common metal salts (zinc nitrate, cobalt nitrate, etc.) and chemicals (NH4F, hexamethylenetetramine), with a unit price of less than 50 yuan / kg. The process steps are simplified (only 3 core operations). The total production time of existing multi-step processes (such as "precursor preparation - high temperature calcination - surface modification") is about 48 hours, while the total production time of the process of this invention is about 24-36 hours (4-12 hours of hydrothermal reaction + 10-30 hours of drying), which improves the production efficiency by more than 50% compared with the existing process. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a flowchart of a high specific surface area and highly active metal hydroxide and its preparation method according to an embodiment of the present invention; Figure 2 This is a scanning electron microscope (SEM) image of the flower-like hierarchical zinc cobalt hydroxide prepared in Example 1. Figure 3 The image shows a scanning electron microscope (SEM) image of the hollow spherical needle-shaped zinc manganese hydroxide prepared in Example 2. Figure 4 The image shows a scanning electron microscope (SEM) image of the urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres prepared in Example 3. Figure 5 The image shows a scanning electron microscope (SEM) image of the thin-walled hollow nanospheres of manganese-cobalt bimetallic hydroxide prepared in Example 4. Detailed Implementation

[0026] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0027] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0029] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The illustrations only show the components related to this application and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0030] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details.

[0031] This application proposes a general method for template-free and controllable preparation of high specific surface area and highly active binary / ternary metal hydroxides (metal elements include zinc, cobalt, manganese, nickel, copper, etc.) through synergistic additive combination regulation and stepped temperature-controlled hydrothermal process. The prepared materials can be widely used in new energy fields such as lithium-ion batteries, aqueous batteries (zinc-ion batteries, ammonium-ion batteries, etc.), metal-air batteries, supercapacitors, and electrocatalysis. The content of this application is described in detail below.

[0032] In a first aspect, embodiments of this application provide a method for preparing a high specific surface area, highly active metal hydroxide, referring to... Figure 1 ,include: S1. Preparation of precursor solution: At room temperature, dissolve a binary or ternary metal source in deionized water and stir magnetically to form a clear metal salt solution (until transparent, ensuring uniform dispersion of metal ions); add ammonium fluoride, hexamethylenetetramine, and a surfactant selectively added for the binary or ternary metal source to the metal salt solution in sequence, and stir magnetically until uniformly mixed to obtain the precursor solution; S2. Stepped temperature-controlled hydrothermal reaction: The precursor solution is heated using a two-stage temperature-controlled mode of low-temperature induced nucleation and medium-temperature directional growth. The temperature of the low-temperature induced nucleation stage is controlled at 10-40℃, and the reaction is carried out at a constant temperature for 0.5-2 hours to form a large number of uniform initial crystal nuclei with a diameter of 5-20 nm. The temperature of the medium-temperature directional growth stage is controlled at 60-100℃, and the reaction is carried out at a constant temperature for 4-12 hours to drive the crystal nuclei to grow along preferred crystal planes and form the target hierarchical structure through the Ostwald ripening effect. S3. Post-processing: After the reaction system is naturally cooled to room temperature, the precipitate is collected, washed and dried to obtain the target metal hydroxide. Among them, by adjusting the molar ratio of various metal ions in a binary or ternary metal source, target metal hydroxides with different structures can be obtained.

[0033] In this embodiment, the core of step S1 is the precise matching of the synergistic additive and the multi-metal source, wherein the role of ammonium fluoride is to slowly release OH... - To regulate the pH rise evenly while providing F - Hexamethylenetetramine forms weak coordination bonds with metal ions, jointly inducing the directional growth of polygonal / needle-shaped crystal faces. The role of hexamethylenetetramine is to regulate the crystal growth rate through weak coordination, inhibit nanoparticle aggregation, and synergistically optimize the crystal face growth direction with ammonium fluoride. Step S2 focuses on the phased regulation of the nucleation-growth-self-assembly process; the first stage is induced nucleation, and the second stage is directional growth and self-assembly. Step S3 focuses on preserving the structure and removing impurities. This method requires no template agents (including but not limited to carbon spheres and polymer microspheres), and the hollow structure spontaneously forms through the Ostwald ripening effect and the interfacial adsorption of synergistic additives.

[0034] Therefore, this embodiment achieves template-free controllable preparation of binary / ternary metal hydroxides with multiple morphologies through the coupling effect of "synergistic additive regulation of crystal growth direction" and "step temperature control of nucleation-growth-self-assembly sequence".

[0035] Furthermore, the binary metal source includes, but is not limited to, a combination of zinc and cobalt sources, a combination of zinc and manganese sources, or a combination of manganese and cobalt sources; the ternary metal source includes, but is not limited to, a combination of zinc, cobalt, and manganese sources; the zinc source is selected from zinc nitrate, zinc chloride, or zinc sulfate; the cobalt source is selected from cobalt nitrate, cobalt chloride, or cobalt sulfate; and the manganese source is selected from manganese nitrate, manganese chloride, or manganese sulfate.

[0036] Furthermore, the method of obtaining target metal hydroxides with different structures by adjusting the molar ratio of various metal ions in a binary or ternary metal source includes: Binary system: Regulating the zinc ion (Zn) composition in the combination of zinc and cobalt sources. 2+ ) and cobalt ions (Co) 2+ When the molar ratio of ) is 1:1 to 3:1, a flower-like hierarchical zinc-cobalt hydroxide is obtained. 2+ Excessive promotion of polygonal nanosheet growth; Binary system: Regulating the zinc ion (Zn) composition in the combination of zinc and manganese sources. 2+ ) and manganese ions (Mn 2+ When the molar ratio of Mn to manganese hydroxide is 1:1-3:2, hollow spherical needle-shaped zinc-manganese hydroxide is obtained. 2+ The length of the needle-like protrusions can be adjusted proportionally. Binary system: regulating manganese ions (Mn) in the combination of manganese and cobalt sources 2+ ) and cobalt ions (Co) 2+ When the molar ratio of manganese cobalt bimetallic hydroxide is 0.3:0.7-0.7:0.3, thin-walled hollow nanospheres of manganese cobalt bimetallic hydroxide are obtained. When the molar ratio is close to 1:1, uniform thin walls are easily formed. Ternary system: regulating the combination of zinc, cobalt, and manganese sources to produce zinc ions (Zn). 2+ ), cobalt ions (Co) 2+ ) and manganese ions (Mn 2+ When the molar ratio of zinc, cobalt, and manganese is (1-3):(1-3):(1-3), urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres are obtained, and the ternary components synergistically enhance the electrochemical activity.

[0037] In one embodiment, the reaction environment and temperature control parameters are precisely matched according to the target product structure: when the target metal hydroxide is a flower-shaped zinc-cobalt hydroxide or a hollow spherical needle-shaped zinc-manganese hydroxide, the step-temperature controlled hydrothermal reaction adopts a water bath environment, the temperature of the low-temperature induced nucleation stage is 25-30℃, and the temperature of the medium-temperature directional growth stage is 80-90℃. When the target metal hydroxide is a sea urchin-shaped zinc-cobalt-manganese ternary hollow nanosphere or a manganese-cobalt bimetallic hydroxide thin-walled hollow nanosphere, the stepped temperature-controlled hydrothermal reaction is carried out in a hydrothermal reactor (filling degree 60-80%) or an oil bath environment. The temperature of the low-temperature induced nucleation stage is 20-35℃, and the temperature of the medium-temperature directional growth stage is 85-95℃.

[0038] In one embodiment, the total concentration of metal ions in the metal salt solution is 0.05-3 mol / L, the molar ratio of ammonium fluoride to total metal ions is 0.5:1-2:1, and the molar ratio of hexamethylenetetramine to total metal ions is 1:1-3:1.

[0039] Preferably, the total concentration of metal ions in the metal salt solution is 0.1-0.15 mol / L, which avoids low yield due to too low a concentration and easy agglomeration due to too high a concentration.

[0040] Furthermore, the surfactant selectively added for the ternary metal source is polyvinylpyrrolidone (PVP), with a mass ratio of PVP to metal ions of 0.01:1-0.05:1. The role of PVP is to guide the self-assembly of the ternary system to form a sea urchin-like hollow structure. The surfactant selectively added for the binary metal source is hexadecyltrimethylammonium bromide or sodium dodecyl sulfate, with a concentration of hexadecyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) of 0.01-0.1 mol / L. The role of CTAB and SDS is to regulate the formation of thin-walled hollow and spherical secondary structures in the manganese-cobalt system.

[0041] In one embodiment, collecting the precipitate and washing and drying the precipitate includes: Collect the precipitate by centrifugation or filtration. The centrifugation speed is 3000-12000 rpm and the centrifugation time is 5-15 minutes. Wash the precipitate 3-5 times alternately with deionized water and anhydrous ethanol until the pH of the washing solution is 6.5-7.5; The washed product is placed in a vacuum oven for drying at a temperature of 60-100℃ for 10-30 hours.

[0042] Furthermore, in step S3, the post-processing parameters are adapted to the target product structure to avoid structural collapse: if the target metal hydroxide is a flower-like hierarchical zinc-cobalt hydroxide or a hollow spherical needle cluster type zinc-manganese hydroxide, the centrifugation speed is 3000-8000 rpm, the drying temperature is 80-90℃, and the drying time is 15-20 hours. If the target metal hydroxide is a sea urchin-shaped zinc-cobalt-manganese ternary hollow nanosphere or a manganese-cobalt bimetallic hydroxide thin-walled hollow nanosphere, the centrifugation speed is 8000-12000 rpm, the drying temperature is 60-80℃, and the drying time is 20-24 hours.

[0043] In one specific embodiment, the method for preparing the high specific surface area and highly active metal hydroxide includes the following steps: S1. Precursor solution preparation: Precise matching of synergistic additives and multi-metal sources. The key to this step is to design additive combinations based on the target product (binary / ternary, specific morphology), and guide the initial crystal growth direction through the synergistic effect of different components. S1.1 Preparation of multi-metal salt solution: At room temperature, select the corresponding metal source according to the metal system of the target product, dissolve it in deionized water, and stir magnetically for 10-30 minutes until transparent to ensure uniform dispersion of metal ions. The total concentration of metal ions is controlled at 0.05-0.5 mol / L (preferably 0.1-0.15 mol / L, to avoid low yield due to excessively low concentration and agglomeration due to excessively high concentration), and the ion molar ratio for different systems is adapted as follows: Binary zinc-cobalt system (floral product): Zn 2+ :Co 2+ =1:1-3:1(Co 2+ (Excessive promotion of polygonal nanosheet growth); Binary zinc-manganese system (hollow spherical needle-like cluster product): Zn 2+ :Mn 2+ =1:1-3:2(Mn 2+ (Proportional adjustment of needle-like protrusion length); Binary manganese-cobalt system (thin-walled hollow products): Mn 2+ :Co 2+ =0.3:0.7-0.7:0.3 (When the molar ratio is close to 1:1, it is easy to form a uniform thin wall). Ternary zinc-cobalt-manganese system (urchin-like hollow product): Zn 2+ :Co 2+ :Mn 2+ =(1-3):(1-3):(1-3)(The ternary components synergistically enhance electrochemical activity).

[0044] S1.2, Introduction of synergistic additives: Add the components according to the logic of "basic synergist + system-specific surfactant" (for zinc-cobalt binary systems and zinc-manganese binary systems, no surfactant is required), ensuring that the functions of each component are complementary, and stir magnetically for 20-40 minutes until homogeneous. Basic synergists (essential for all systems): Ammonium fluoride (NH4F) and hexamethylenetetramine; NH4F slowly releases F. - It forms weak coordination bonds with metal ions to induce the growth of specific crystal planes (such as the (101) plane); hexamethylenetetramine slowly hydrolyzes to produce OH - To avoid particle agglomeration caused by a sudden increase in pH, the molar ratio of the two to the total molar ratio of metal ions is 0.5:1-2:1 and 1:1-3:1, respectively, and the two work together to optimize the crystal growth direction. System-specific surfactants (added as needed): PVP (mass ratio 0.01:1-0.05:1) is added to the ternary system to guide the self-assembly of the hollow structure through steric hindrance; CTAB / SDS (concentration 0.01-0.1mol / L) is added to the "manganese-cobalt binary system" to regulate the thin-wall thickness and fluffy secondary structure through interfacial adsorption.

[0045] S2, Stepped Temperature-Controlled Hydrothermal Reaction: This step controls nucleation, growth, and self-assembly in stages. It achieves "uniform nucleation followed by directional growth" through two-stage temperature control, avoiding the structural inhomogeneity problems caused by traditional isothermal reactions. The first stage (induced nucleation): isothermal at 10-40℃ for 0.5-2 hours. The low temperature environment inhibits the rapid growth of crystal nuclei and ensures the formation of a large number of uniform crystal nuclei with a diameter of 5-20 nm (crystal nucleus size difference <20%), laying the foundation for subsequent hierarchical structures. The nucleation temperature varies slightly for different systems: 25-30℃ for binary systems and 20-35℃ for ternary systems. The second stage (directed growth and self-assembly): The temperature is raised to 60-100℃ and held for 4-12 hours. The intermediate temperature drives the growth of crystal nuclei along preferred crystal planes, while simultaneously, hollow structures are spontaneously formed through the Ostwald ripening effect (dissolution of small particles and deposition of large particles). Zinc-cobalt system: polygonal nanosheets are stacked in an interlaced manner to form a flower-like structure; Zinc-manganese system: Needle-like protrusions grow on the surface of the hollow substrate, forming hollow spherical needle clusters; Zinc-cobalt-manganese system: needle-like spines grow on the hollow spherical wall, forming a sea urchin-like structure; Manganese-cobalt system: thin-walled spherical shells are formed and fluffy secondary structures are grown to obtain thin-walled hollow nanospheres.

[0046] S3. Post-processing: Preserve structure and remove impurities; adjust parameters according to product structure stability to prevent structural collapse. Product collection: For larger flower-shaped / hollow spherical needle clusters, centrifuge at 3000-8000 rpm; for smaller, thin-walled sea urchin-shaped / thin-walled hollow particles, centrifuge at 8000-12000 rpm (to avoid loss of small particles). Impurity removal: Wash with deionized water and anhydrous ethanol alternately 3-5 times (ethanol can reduce surface tension and prevent structural agglomeration) until pH=6.5-7.5 (to ensure no residual additives). Drying and shape preservation: Low-temperature vacuum drying (60-100℃) for 10-30 hours. Flower-shaped / hollow spherical needle clusters have better temperature resistance and should be dried at 80-90℃. Sea urchin-shaped / thin-walled hollow structures are prone to collapse and should be dried at 60-80℃ to avoid structural shrinkage caused by high temperature.

[0047] Secondly, embodiments of this application also provide a high specific surface area and high activity metal hydroxide, prepared by the preparation method described in any embodiment of the first aspect, wherein the high specific surface area and high activity metal hydroxide is any one of the following: Flower-like hierarchical zinc-cobalt hydroxide: It has a three-dimensional flower-like structure, composed of interlaced polygonal nanosheets with side lengths of 80-120 nm and diameters of 2-3 μm, with a specific surface area of ​​50-200 m². 2 / g; Hollow spherical needle-like zinc-manganese hydroxide: This structure consists of needle-like protrusions with a length of 50-100 nm growing on the surface of a hollow substrate. The diameter of the hollow substrate is 1-2 μm, and the specific surface area is increased by 30-50% compared with the traditional solid spherical structure. Manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres: These are thin-walled spherical shells with velvety secondary structures, ranging in diameter from 100 to 500 nm, wall thickness from 5 to 20 nm, and specific surface area from 200 to 300 m². 2 / g; Ulcer-like zinc-cobalt-manganese ternary hollow nanospheres: These are structures with needle-like spikes growing on the hollow sphere walls for 20-100 nm in length, a sphere diameter of 100-500 nm, a hollow portion diameter of 50-300 nm, a wall thickness of 10-30 nm, and a specific surface area of ​​250-400 m². 2 / g.

[0048] Thirdly, embodiments of this application provide an application of high specific surface area and high activity metal hydroxide as described in the second aspect, using flower-like hierarchical zinc-cobalt hydroxide, urchin-like zinc-cobalt-manganese ternary hollow nanospheres, or manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres to prepare the positive electrode of a zinc-ion battery; Alternatively, a catalytic layer for zinc-air batteries can be prepared using hollow spherical needle-shaped zinc-manganese hydroxide, where the needle-like protrusions and hollow structure of the material synergistically enhance oxygen adsorption capacity. Alternatively, manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres or urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres can be used to prepare electrode active materials for supercapacitors. Alternatively, urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres can be used to prepare the negative electrode for lithium-ion batteries.

[0049] The preparation methods and application effects of four metal hydroxides are described in detail below.

[0050] Example 1: Preparation of a flower-like hierarchical zinc cobalt hydroxide.

[0051] S1.1 Preparation of metal salt solution: Weigh 0.01 mol of zinc nitrate (Zn(NO3)2) 6H2O) and 0.01 mol cobalt nitrate (Co(NO3)2) 6H2O)(Zn 2+ :Co 2+ =1:1, total molar concentration of metal ions = 0.02 mol), dissolved in 100 mL of deionized water, and magnetically stirred at room temperature for 20 minutes to form a homogeneous pink solution (total concentration of metal ions 0.1 mol / L, which is within the preferred concentration range). S1.2 Introduction of synergistic additives: Add 0.02 mol ammonium fluoride (NH4F: metal ions = 1:1) and 0.03 mol hexamethylenetetramine (hexamethylenetetramine: metal ions = 1.5:1), and stir magnetically for 30 minutes until uniformly mixed (no surfactant is required for the zinc-cobalt binary system). S2, Stepped temperature-controlled hydrothermal reaction: The mixed solution is transferred to a water bath environment. The first stage is held at 25°C for 1 hour (inducing nucleation), and the second stage is heated to 80°C and held at 8 hours (directional growth). S3. Post-treatment: After naturally cooling to room temperature, the precipitate was collected by centrifugation at 5000 rpm for 10 minutes; it was washed 4 times alternately with deionized water and anhydrous ethanol until the pH of the washing solution was 7.0; it was dried in a vacuum oven at 80℃ for 20 hours to obtain a flower-like hierarchical zinc cobalt hydroxide.

[0052] Product characterization: Refer to Figure 2 The product has a three-dimensional flower-like structure with polygonal nanosheets having a side length of 80-120 nm and a specific surface area of ​​120 m² / g. As a positive electrode for zinc-ion batteries, it has a specific capacity of 320 mAh / g (@1 A / g) and a capacity retention rate of 92% after 5000 cycles.

[0053] Example 2: Preparation of hollow spherical needle-shaped zinc manganese hydroxide.

[0054] S1.1 Preparation of metal salt solution: Weigh 0.012 mol zinc chloride (ZnCl2) and 0.008 mol manganese nitrate (Mn(NO3)2) 4H2O)(Zn 2+ :Mn 2+=3:2, total molar concentration of metal ions = 0.02mol), dissolved in 100mL of deionized water, stirred at room temperature for 15 minutes to form a homogeneous and transparent solution (total concentration of metal ions 0.1mol / L, which is within the preferred concentration range). S1.2 Introduction of synergistic additives: Add 0.04 mol ammonium fluoride (NH4F: metal ions = 2:1) and 0.03 mol hexamethylenetetramine (hexamethylenetetramine: metal ions = 1.5:1), and stir magnetically for 30 minutes (no surfactant is needed for the zinc-manganese binary system). S2, Stepped temperature controlled hydrothermal reaction: The mixed solution is transferred to an oil bath environment. The first stage is held at 30℃ for 1 hour (nucleation), and the second stage is heated to 90℃ and held at 90℃ for 6 hours (growth). S3. Post-treatment: The precipitate was collected by filtration and washed 4 times alternately with deionized water and anhydrous ethanol until the pH of the washing solution was 6.8; it was then vacuum dried at 90°C for 15 hours to obtain hollow spherical needle-shaped zinc-manganese hydroxide.

[0055] Product characterization: Refer to Figure 3 The hollow substrate has a diameter of 1-2 μm, needle-like protrusions are 50-80 nm long, and a specific surface area of ​​180 m². 2 / g; as a zinc-air battery catalyst layer, the ORR half-wave potential is 0.87V (vs. RHE), and the OER overpotential is 310mV (@10mA / cm). 2 Its catalytic stability exceeds 200 hours.

[0056] Example 3: Preparation of sea urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres.

[0057] S1.1 Preparation of metal salt solution: Weigh out 0.005 mol zinc nitrate, 0.005 mol cobalt nitrate, and 0.005 mol manganese nitrate (Zn). 2+ :Co 2+ :Mn 2+ =1:1:1, total molar concentration of metal ions = 0.015 mol), dissolved in 100 mL of deionized water, stirred at room temperature for 20 minutes to form a homogeneous solution (total concentration of metal ions 0.15 mol / L, which is within the preferred concentration range). S1.2 Introduction of synergistic additives: Add 0.0225 mol ammonium fluoride (NH4F: metal ions = 1.5:1), 0.045 mol hexamethylenetetramine (hexamethylenetetramine: metal ions = 3:1) and 0.0015 g PVP (PVP: total mass of metal ions = 0.03:1), and stir magnetically for 40 minutes until homogeneous; S2, Stepped temperature controlled hydrothermal reaction: The mixed solution is transferred to a hydrothermal reactor (70% filling). The first stage is held at 20℃ for 2 hours (nucleation). The second stage is heated to 85℃ and held at 85℃ for 10 hours (growth). S3. Post-treatment: The precipitate was collected by centrifugation at 6000 rpm for 8 minutes and washed until pH=7.2; it was then vacuum dried at 75℃ for 24 hours to obtain sea urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres.

[0058] Product characterization: Refer to Figure 4 The sphere diameter is 200-400 nm, the hollow diameter is 100-200 nm, the needle-like spine length is 30-80 nm, and the specific surface area is 320 m². 2 / g; as a negative electrode for lithium-ion batteries, it has a specific capacity of 480mAh / g (@0.5A / g) and a capacity retention rate of 88% after 5000 cycles.

[0059] Example 4: Preparation of thin-walled hollow nanospheres of manganese-cobalt bimetallic hydroxide.

[0060] S1.1 Preparation of metal salt solution: Weigh 0.007 mol manganese nitrate and 0.003 mol cobalt nitrate (Mn) 2+ :Co 2+ =7:3, total molar concentration of metal ions = 0.01 mol), dissolved in 100 mL of deionized water, stirred at room temperature for 25 minutes to form a homogeneous solution (total concentration of metal ions 0.1 mol / L, which is within the preferred concentration range). S1.2 Introduction of synergistic additives: Add 0.015 mol ammonium fluoride (NH4F: total molar of metal ions = 1.5:1), 0.03 mol hexamethylenetetramine (hexamethylenetetramine: total molar of metal ions = 3:1) and 0.001 mol CTAB (CTAB concentration = 0.01 mol / L), sonicate for 10 minutes (to promote CTAB dispersion) and then magnetically stir for 30 minutes; S2, Stepped temperature-controlled hydrothermal reaction: The mixed solution is transferred to an oil bath environment. The first stage is held at 35℃ for 1.5 hours (nucleation), and the second stage is heated to 95℃ and held at 95℃ for 8 hours (growth). S3. Post-treatment: The precipitate was collected by centrifugation at 8000 rpm for 5 minutes and washed until pH=7.0; it was then vacuum dried at 80℃ for 18 hours to obtain thin-walled hollow nanospheres of manganese cobalt bimetallic hydroxide.

[0061] Product characterization: Refer to Figure 5 The spheres have a diameter of 150-300 nm, a wall thickness of 8-15 nm, and a surface with a fluffy secondary structure, resulting in a specific surface area of ​​250 m² / g. 2 / g; as a supercapacitor electrode, it has a specific capacitance of 2200F / g (@5mV / s) and a capacitance retention of 68% at 10A / g.

[0062] The embodiments provided by this invention have advantages in three dimensions: structural innovation, technological breakthrough, and improved economic efficiency, and each advantage is supported by clear data: (1) Structural and performance innovation: to resolve the contradiction between mass transfer efficiency and stability.

[0063] Through the coupling effect of "synergistic additives + step temperature control", precise regulation of microstructure is achieved: Specific surface area is significantly increased: reaching 50-400 m² 2 / g, compared to traditional coprecipitation methods (≤50m) 2 / g) is increased by 2-5 times, compared with the conventional hydrothermal method (≤150m) 2 / g) increased by 1.5-2.5 times; High active site exposure rate: >80%, more than double that of existing technologies (<40%); Excellent electrochemical performance: battery specific capacity 250-500mAh / g (@1A / g), supercapacitor specific capacitance 1600-3000F / g (@5mV / s), retention rate >85% after 5000 cycles, which is more than 10 times more stable than the manganese cobalt hydroxide in the existing publicly available technology (retention rate <70% after 500 cycles).

[0064] (2) Process versatility and controllability: It is adaptable to diverse systems and does not require complex equipment.

[0065] Wide system adaptability: It can cover the entire binary (zinc-cobalt, zinc-manganese, manganese-cobalt) and ternary (zinc-cobalt-manganese) system without the need to develop new processes for a single system; Template-free and conventional equipment: No expensive template agents are required (reducing raw material costs by 30-50%), and conventional water bath / oil bath / hydrothermal reactor equipment is used, eliminating the need for high-temperature and high-pressure devices (reducing equipment investment by 40%). High process repeatability: Through precise parameter control, the structural difference between batches is <5%, and the repeatability is >95%, meeting the needs of large-scale production.

[0066] (3) Green economy: It meets the requirements of industrialization in terms of environmental protection and cost.

[0067] Green and environmentally friendly: The preparation process produces no toxic or harmful substances (such as no fluoride-containing wastewater or organic waste liquid), and the post-treatment washing liquid can be recycled (reducing wastewater discharge by 60%). Low cost: The raw materials are common metal salts (zinc nitrate, cobalt nitrate, etc.) and chemicals (NH4F, hexamethylenetetramine), with a unit price of less than 50 yuan / kg. The process steps are simplified (only 3 core operations). The total production time of existing multi-step processes (such as "precursor preparation - high temperature calcination - surface modification") is about 48 hours, while the total production time of the process of this invention is about 24-36 hours (4-12 hours of hydrothermal reaction + 10-30 hours of drying), which improves the production efficiency by more than 50% compared with the existing process.

[0068] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for preparing a high specific surface area, highly active metal hydroxide, characterized in that, include: Precursor solution preparation: At room temperature, a binary or ternary metal source is dissolved in deionized water and magnetically stirred to form a clear metal salt solution; Ammonium fluoride, hexamethylenetetramine, and a surfactant selectively added for a binary or ternary metal source are added sequentially to the metal salt solution, and the mixture is magnetically stirred until homogeneous to obtain a precursor solution. Stepped temperature-controlled hydrothermal reaction: The precursor solution is heated in a two-stage temperature-controlled mode of low-temperature induced nucleation and medium-temperature directional growth. The temperature of the low-temperature induced nucleation stage is controlled at 10-40℃ and the reaction is kept at a constant temperature for 0.5-2 hours; the temperature of the medium-temperature directional growth stage is controlled at 60-100℃ and the reaction is kept at a constant temperature for 4-12 hours. Post-processing: After the reaction system is naturally cooled to room temperature, the precipitate is collected, washed, and dried to obtain the target metal hydroxide; Among them, by adjusting the molar ratio of various metal ions in a binary or ternary metal source, target metal hydroxides with different structures can be obtained.

2. The preparation method according to claim 1, characterized in that, The binary metal source includes, but is not limited to, a combination of zinc and cobalt, a combination of zinc and manganese, or a combination of manganese and cobalt. The ternary metal source includes, but is not limited to, a combination of zinc, cobalt, and manganese. The zinc source is selected from zinc nitrate, zinc chloride, or zinc sulfate. The cobalt source is selected from cobalt nitrate, cobalt chloride, or cobalt sulfate. The manganese source is selected from manganese nitrate, manganese chloride, or manganese sulfate.

3. The preparation method according to claim 2, characterized in that, The method of obtaining target metal hydroxides with different structures by adjusting the molar ratio of various metal ions in a binary or ternary metal source includes: When the molar ratio of zinc ions to cobalt ions in the combination of zinc and cobalt sources is adjusted to 1:1-3:1, a flower-like hierarchical zinc-cobalt hydroxide is obtained. When the molar ratio of zinc ions to manganese ions in the combination of zinc and manganese sources is adjusted to 1:1-3:2, hollow spherical needle-shaped zinc-manganese hydroxide is obtained. By adjusting the molar ratio of manganese ions to cobalt ions in the combination of manganese and cobalt sources to 0.3:0.7-0.7:0.3, thin-walled hollow nanospheres of manganese-cobalt bimetallic hydroxide were obtained. By adjusting the molar ratio of zinc ions, cobalt ions, and manganese ions in the combination of zinc, cobalt, and manganese sources to (1-3):(1-3):(1-3), urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres were obtained.

4. The preparation method according to claim 3, characterized in that, When the target metal hydroxide is a flower-shaped zinc-cobalt hydroxide or a hollow spherical needle-shaped zinc-manganese hydroxide, the stepped temperature-controlled hydrothermal reaction adopts a water bath environment, with the temperature of the low-temperature induced nucleation stage being 25-30℃ and the temperature of the medium-temperature directional growth stage being 80-90℃. When the target metal hydroxide is a sea urchin-shaped zinc-cobalt-manganese ternary hollow nanosphere or a manganese-cobalt bimetallic hydroxide thin-walled hollow nanosphere, the stepped temperature-controlled hydrothermal reaction adopts a hydrothermal reactor or oil bath environment, the temperature of the low-temperature induced nucleation stage is 20-35℃, and the temperature of the medium-temperature directional growth stage is 85-95℃.

5. The preparation method according to claim 1, characterized in that, The total concentration of metal ions in the metal salt solution is 0.05-3 mol / L, the molar ratio of ammonium fluoride to total metal ions is 0.5:1-2:1, and the molar ratio of hexamethylenetetramine to total metal ions is 1:1-3:

1.

6. The preparation method according to claim 2, characterized in that, The surfactant selectively added for the ternary metal source is polyvinylpyrrolidone, with a mass ratio of polyvinylpyrrolidone to total metal ions of 0.01:1-0.05:1; the surfactant selectively added for the binary metal source is hexadecyltrimethylammonium bromide or sodium dodecyl sulfate, with a concentration of hexadecyltrimethylammonium bromide or sodium dodecyl sulfate of 0.01-0.1 mol / L.

7. The preparation method according to claim 3, characterized in that, The collection of precipitates, and the washing and drying of the precipitates, includes: Collect the precipitate by centrifugation or filtration. The centrifugation speed is 3000-12000 rpm and the centrifugation time is 5-15 minutes. Wash the precipitate 3-5 times alternately with deionized water and anhydrous ethanol until the pH of the washing solution is 6.5-7.5; The washed product is placed in a vacuum oven for drying at a temperature of 60-100℃ for 10-30 hours.

8. The preparation method according to claim 7, characterized in that, If the target metal hydroxide is a flower-like hierarchical zinc-cobalt hydroxide or a hollow spherical needle-like zinc-manganese hydroxide, the centrifugation speed is 3000-8000 rpm, the drying temperature is 80-90℃, and the drying time is 15-20 hours. If the target metal hydroxide is a sea urchin-shaped zinc-cobalt-manganese ternary hollow nanosphere or a manganese-cobalt bimetallic hydroxide thin-walled hollow nanosphere, the centrifugation speed is 8000-12000 rpm, the drying temperature is 60-80℃, and the drying time is 20-24 hours.

9. A high specific surface area, highly active metal hydroxide, characterized in that, The high specific surface area and highly active metal hydroxide is prepared by the preparation method according to any one of claims 1-8, wherein the high specific surface area and highly active metal hydroxide is any one of the following: Flower-like hierarchical zinc-cobalt hydroxide: It has a three-dimensional flower-like structure, composed of interlaced polygonal nanosheets with side lengths of 80-120 nm and diameters of 2-3 μm, with a specific surface area of ​​50-200 m². 2 / g; Hollow spherical needle cluster type zinc manganese hydroxide: It is a structure with needle-like protrusions with a length of 50-100 nm growing on the surface of a hollow substrate, and the diameter of the hollow substrate is 1-2 μm; Manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres: These are thin-walled spherical shells with velvety secondary structures, ranging in diameter from 100 to 500 nm, wall thickness from 5 to 20 nm, and specific surface area from 200 to 300 m². 2 / g; Ulcer-like zinc-cobalt-manganese ternary hollow nanospheres: These are structures with needle-like spikes growing on the hollow sphere walls for 20-100 nm in length, a diameter of 100-500 nm, a hollow portion diameter of 50-300 nm, a wall thickness of 10-30 nm, and a specific surface area of ​​250-400 m². 2 / g.

10. An application of the high specific surface area, highly active metal hydroxide as described in claim 9, characterized in that, The positive electrode of a zinc-ion battery is prepared using a flower-like hierarchical zinc-cobalt hydroxide, an urchin-like zinc-cobalt-manganese ternary hollow nanosphere, or a manganese-cobalt bimetallic hydroxide thin-walled hollow nanosphere. Alternatively, a catalytic layer for zinc-air batteries can be prepared using hollow spherical needle-shaped zinc-manganese hydroxide. Alternatively, manganese-cobalt bimetallic hydroxide thin-walled hollow nanospheres or urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres can be used to prepare electrode active materials for supercapacitors. Alternatively, urchin-shaped zinc-cobalt-manganese ternary hollow nanospheres can be used to prepare the negative electrode for lithium-ion batteries.

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