Antimony monatomic supported carbon nanorings material, preparation method and sodium ion battery application thereof

Abstract

This invention provides an antimony single-atom-loaded carbon nanoring material, its preparation method, and its application in sodium-ion batteries, belonging to the field of electrochemical energy storage technology. First, Sb₂O₃ nanoparticles are loaded onto the surface of g-C₃N₄ nanorings to form a g-C₃N₄@Sb₂O₃ composite structure. Then, a g-C₃N₄@Sb₂O₃@PDA nested composite structure is constructed through polydopamine (PDA) coating. The resulting composite material is then carbonized at high temperature, undergoing reverse Ostwald ripening. The Sb₂O₃ nanoparticles are transformed in situ into highly dispersed antimony single atoms, which are anchored to a nitrogen-doped carbon substrate through Sb-N₄ coordination bonds. This invention uses the carbon nanoring material as the anode in sodium-ion batteries. The atomically dispersed antimony achieves an atomically alloyed sodium storage mechanism dominated by pseudocapacitance, effectively overcoming the shortcomings of traditional antimony-carbon composite materials, such as large volume expansion and poor cycle stability. The carbon nanoring material exhibits ultra-long cycle life and excellent rate performance, showing broad application prospects in advanced energy storage fields.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical energy storage technology, and relates to an antimony single-atom supported carbon nanoring material, its preparation method and its application in sodium-ion batteries, especially an antimony single-atom supported carbon nanoring material and its application in the negative electrode of sodium-ion batteries. Background Technology

[0002] With the rapid development of portable electronic devices, new energy vehicles, and large-scale energy storage systems, the demand for advanced energy storage devices is increasing. Sodium-ion batteries (SIBs), due to their abundant resources and low cost, are considered a potential alternative and complement to lithium-ion batteries (LIBs), especially with broad application prospects in large-scale energy storage and low-speed electric vehicles. Developing anode materials that combine high energy density, high power density, and long cycle life is one of the key steps in promoting the commercial application of sodium-ion batteries.

[0003] Antimony is due to its high theoretical sodium storage capacity (approximately 660 mA hg). -1 ) and suitable operating potential (0.6 V vs Na) + Antimony-based materials, particularly those containing sodium (Na), have become a research hotspot in SIB anode materials. However, antimony-based materials experience significant volume expansion (~390%) during charge and discharge, leading to active material agglomeration and electrode material pulverization, ultimately resulting in rapid capacity decay. To mitigate this issue, current technologies primarily employ nanostructure design on carbon substrates, such as creating hollow or porous structures (CN115863654B, CN 110247030 B), to provide buffer space for antimony volume expansion. With the continuous development of nanoengineering technology, reducing the size of active species has gradually become an effective measure to improve the sodium storage performance of antimony-based composite materials.

[0004] In recent years, single-atom materials (SAMs) have offered new insights into maximizing the utilization of active metal species due to their atomically dispersed characteristics. Anchoring antimony in single-atom form on a conductive carbon substrate can solve the problems of volume expansion and agglomeration. The strong coordination structure formed between the single atom and the substrate can reshape the electronic structure of the substrate and stabilize the active sites. However, existing research on single-atom materials has largely focused on transition metals (such as Fe, Co, and Ni). Although they can effectively modulate the composition of the solid electrolyte interface or sodium adsorption energy, thereby improving the electrochemical performance of SIBs, their theoretical specific capacity is relatively low.

[0005] Therefore, combining the high theoretical capacity of antimony with the advantages of single-atom materials to develop a structurally stable antimony single-atom anode material with excellent sodium storage performance has significant research and application value. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing antimony-carbon composite materials, such as poor cycle stability due to volume expansion and low energy density of existing single-atom materials, and to provide an antimony single-atom-loaded carbon nanoring material, its preparation method, and its applications. This invention achieves a pseudocapacitive-dominated atomic alloying sodium storage mechanism through the strong coordination between atomically dispersed antimony and a nitrogen-doped carbon substrate, thereby endowing the material with high capacity, ultra-long cycle life, and excellent rate performance.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for preparing antimony single-atom-supported carbon nanoring materials involves uniformly dispersing and anchoring antimony in single-atom form onto nitrogen-doped carbon nanorings via a reverse Oswald ripening process, whereby the antimony single atoms form an Sb-N4 coordination structure with the nitrogen in the nitrogen-doped carbon nanorings. The method includes the following steps: Step (1) The preparation process of g-C3N4@Sb2O3 composite material is as follows: using g-C3N4 nanorings as templates; using antimony acetate as antimony source, the hydrothermal reaction is completed by hydrothermal method, and Sb2O3 nanoparticles are uniformly loaded on the surface of g-C3N4 nanorings. After washing and drying, g-C3N4@Sb2O3 composite material is obtained.

[0008] Furthermore, in step (1), the temperature of the hydrothermal reaction is 160-180°C. o C, the time is 2-4 hours.

[0009] Furthermore, in step (1), the drying temperature is 60-80°C. o C, the time is 12-24 hours.

[0010] Furthermore, in step (1), g-C3N4 nanorings and antimony acetate are simultaneously dispersed in deionized water to form a dispersion.

[0011] The preparation process of the g-C3N4@Sb2O3@PDA composite material in step (2) is as follows: The g-C3N4@Sb2O3 composite material obtained in step (1) is dispersed in a Tris buffer solution, dopamine hydrochloride is added, and the mixture is stirred at room temperature and pressure to allow dopamine to undergo in-situ self-polymerization on the surface of the composite material, forming a polydopamine coating layer, which is a solid product. Then, the solid product is washed multiple times with deionized water and anhydrous ethanol to ensure that unreacted dopamine monomers and byproducts are completely removed. Subsequently, it is dried to obtain the g-C3N4@Sb2O3@PDA composite material.

[0012] Furthermore, in step (2), the mass ratio of g-C3N4@Sb2O3 composite material to dopamine hydrochloride is 1:2-1:4; the stirring reaction time is 12-18 h.

[0013] Furthermore, in step (2), 80-120g of g-C3N4@Sb2O3 composite material is added to every 50-150mL of Tris buffer solution.

[0014] The preparation process of the Sb SAs-CNR composite material in step (3) is as follows: the g-C3N4@Sb2O3@PDA composite material obtained in step (2) is placed under an inert atmosphere for high-temperature carbonization treatment. During this process, the polydopamine layer is carbonized to form a nitrogen-doped carbon shell, the g-C3N4 template is decomposed by heat and removed to form a hollow carbon nanoring structure. At the same time, the Sb2O3 nanoparticles undergo a reverse Ostwald ripening process in the confined space, transforming from nanoparticles into atomically dispersed antimony single atoms, which coordinate with nitrogen atoms in the carbon substrate, and finally obtain the antimony single atom loaded carbon nanoring material, named Sb SAs-CNR.

[0015] Furthermore, the high-temperature carbonization temperature in step (3) is 600-700°C. o C, the carbonization time is 1-3 h, and the inert gas is nitrogen or argon.

[0016] An antimony single-atom-supported carbon nanoring material, prepared by the above-described method, exhibits excellent sodium storage performance. The antimony single atoms are anchored to the nitrogen-doped carbon nanorings via Sb-N4 coordination bonds and are uniformly dispersed. This antimony single-atom-supported carbon nanoring material is applied as an anode active material for SIBs in the energy storage field.

[0017] The principle and innovation of this invention are as follows: This invention, based on a spatial confinement and reverse Oswald ripening strategy, successfully constructs antimony single-atom materials anchored on highly nitrogen-doped carbon nanorings, achieving the loading of atomically dispersed Sb species with a stable Sb-N4 coordination configuration. This unique atomically dispersed structure and strong coordination effect allow antimony single atoms to undergo a surface-controlled pseudocapacitive alloying reaction during sodium storage, rather than the large volume changes inherent in traditional alloying reactions. This effectively avoids pulverization and agglomeration of the electrode material, achieving a balance between high capacity and high stability.

[0018] Compared with the prior art, the beneficial effects of the present invention are: (1) Controllable synthesis of antimony single atoms anchored to carbon nanorings in this invention: By designing a nano-nested structure and a reverse Oswald ripening process, Sb single atoms are firmly anchored in nitrogen-rich carbon matrix with Sb-N4 coordination configuration, thereby achieving controllable and precise synthesis of carbon-based Sb single atom composite materials (2.95-8.42 wt%).

[0019] (2) The pseudocapacitive alloying sodium storage mechanism of this invention: Antimony single atoms and sodium ions can undergo a pseudocapacitive alloying reaction. This process is controlled by surface charge transfer rather than bulk ion diffusion, which not only significantly improves the electrode reaction kinetics, but also overcomes the problems of easy agglomeration and large volume expansion of traditional antimony nanoparticles, thereby significantly improving the electrode lifetime. At the same time, compared with other transition metal single atoms, due to its higher theoretical specific capacity, the Sb single-atom electrode has a higher sodium storage capacity potential.

[0020] (3) Excellent electrochemical performance of the present invention: The antimony single-atom supported carbon nanoring material prepared by the present invention exhibits excellent fast charging capability and ultra-long cycle stability, providing an efficient path for the design of high-performance fast-charging sodium-ion battery anode materials. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the preparation process of the antimony single-atom supported carbon nanoring material in an embodiment of the present invention; Figure 2 This is a scanning electron microscope image of the antimony single-atom-supported carbon nanoring material prepared in Example 1 of the present invention; Figure 3 The X-ray diffraction pattern of the antimony single-atom-supported carbon nanoring material prepared in Example 1 of this invention; Figure 4 The X-ray energy dispersive spectroscopy (EDS) diagrams of the antimony single-atom-supported carbon nanoring material prepared in Example 1 of this invention are shown below. In the diagram, a is a high-angle annular dark-field scanning transmission electron microscope image, b is the C element distribution diagram, c is the N element distribution diagram, d is the O element distribution diagram, and e is the Sb element distribution diagram. Figure 5 This is an aberration-corrected transmission electron microscope image of the antimony single-atom-supported carbon nanoring material prepared in Example 1 of the present invention, with Sb single atoms inside the circle. Figure 6 The extended edge X-ray absorbing fine structure of antimony in the antimony single-atom supported carbon nanoring material prepared in Example 1 of this invention; Figure 7 This is a high-resolution N 1s spectrum of the antimony single-atom-supported carbon nanoring material prepared in Example 1 of the present invention; Figure 8 The antimony single-atom-supported carbon nanoring material prepared in Example 1 of this invention was used as the anode in a sodium-ion battery at 0.1 mV / s. -1 CV curves tested at scan rate; Figure 9 The graph shows the contribution ratio of capacitance and diffusion control capacity of the antimony single-atom supported carbon nanoring material prepared in Example 1 of the present invention at different scan rates. Figure 10The antimony single-atom-supported carbon nanoring material and the nitrogen-doped carbon nanoring material prepared in Example 1 of this invention were used as anodes in sodium-ion batteries at 5 A g. -1 Cyclic performance at current density; Figure 11 The rate performance of the antimony single-atom-supported carbon nanoring material and the nitrogen-doped carbon nanoring material prepared in Example 1 of this invention as sodium-ion battery anodes at different current densities is shown. Detailed Implementation

[0022] The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments.

[0023] In this invention, the raw material g-C3N4 nanorings are prepared according to the patent CN107151003B authorized by our research group (patent application number 2017102900997, patent application number 2017.09.12).

[0024] Example 1 This invention provides a flowchart of a method for preparing antimony single-atom-supported carbon nanoring materials, as shown in the embodiments. Figure 1 As shown, the method includes: (1) Weigh 100 mg g-C3N4 nanorings, 360 mg urea, and 60 mg antimony acetate and disperse them in a mixed solution of 30 mL deionized water to form a dispersion. Transfer the dispersion to a high-pressure hydrothermal reactor for hydrothermal reaction at a temperature of 170 °C. o C, the reaction time was 3 h, and the solid product obtained from the hydrothermal reaction was washed three times with ethanol and water, respectively, at 80 °C. o Dry at C for 12 hours.

[0025] (2) Weigh 100 mg of the solid prepared in step (1) and disperse it in 100 mL of freshly prepared Tris buffer solution. Add 300 mg of dopamine hydrochloride to the buffer solution and stir and polymerize at room temperature for 15 h to coat the surface of the solid product obtained in step (1) with polydopamine. Wash the product obtained after coating with deionized water several times. o Dry at C for 12 h.

[0026] (3) The product obtained in step (2) is calcined under an argon atmosphere at a temperature of 600°C. o At time C, for 3 h, antimony single-atom-supported carbon nanoring materials were obtained.

[0027] The scanning electron microscope (SEM) image of the antimony single-atom-supported carbon nanoring material prepared in this embodiment is shown below. Figure 2 As shown, scanning electron microscopy reveals that the material morphology is a nanoring structure. X-ray diffraction analysis of the antimony single-atom-supported carbon nanoring material, as shown... Figure 3 As shown, the spectrum does not contain characteristic peaks of metal Sb and Sb2O3, ruling out the presence of metal Sb and Sb2O3 in the composite material. Figure 4 X-ray energy dispersive spectroscopy (EDS) analysis results show that the prepared antimony single-atom-supported carbon nanoring material is mainly composed of C, N, O, and Sb elements, and each element is uniformly distributed in the material. The aberration-corrected transmission electron microscopy image of the antimony single-atom-supported carbon nanoring material obtained in this embodiment is shown below. Figure 5 As shown, the bright spots in the circles represent antimony atoms, and it can be seen that each antimony atom is isolated from the others. The X-ray absorption fine structure of the extended edge of the antimony element in the carbon nanoring material supported by antimony single atoms obtained in this embodiment is shown below. Figure 6 As shown, the coordination structure around the antimony atom is displayed, with clearly visible antimony-nitrogen bond peaks and no antimony-antimony or antimony-oxygen bond peaks, proving that the antimony atoms are loaded on the nitrogen-containing carbon group and remain independent of each other. High-resolution N1s spectrum ( Figure 7 The peaks at 398.13, 398.73, 399.85 and 404.18 eV can be decomposed into four peaks, corresponding to pyridine nitrogen, Sb-N coordination bond, pyrrole nitrogen and nitrogen oxide, respectively, proving the successful coordination of Sb with N.

[0028] The antimony single-atom-supported carbon nanoring material prepared in this embodiment was used as a negative electrode material for sodium-ion batteries for electrochemical performance testing. Figure 8 It is at 0.1 mV s -1 The CV curves measured at the scan rate show that the reduction peak in the cathode scan corresponds to the atomic-level alloying reaction of Sb single atoms to form Na. x The Sb mesophase, while the oxidation peak in the anodic scan is related to Na. x The reversible atomic-level dealloying reaction of Sb intermediates (regenerating Sb single atoms) is relevant. The contribution ratios of pseudocapacitance and diffusion-controlled capacity of the antimony single-atom-supported carbon nanoring material prepared in this example at different scan rates are as follows: Figure 9 As shown, at values ​​of 0.1, 0.2, 0.5, 1, and 2 mV s -1 At the scanning rates, the pseudocapacitive contribution of this electrode reached 69%, 75%, 80%, 84% and 90%, respectively, proving that the negative electrode material exhibits sodium storage characteristics dominated by pseudocapacitive behavior.

[0029] like Figure 10 As shown, in terms of cycle performance, at 5 Ag -1 The specific capacity of the antimony single-atom-loaded carbon nanoring material remained at 375.1 mAh g⁻¹ after 5000 cycles at the specified current density. -1 It exhibits excellent cycling stability. Meanwhile, in terms of rate performance, the antimony single-atom-supported carbon nanoring material shows good performance at rates of 0.1, 0.2, 0.5, 1, 2, and 5 g.-1 At current densities of [values ​​missing], their discharge specific capacities are 450.2, 408.5, 381.5, 352.7, 332.8, and 317.2 mA hg, respectively. -1 It is significantly superior to nitrogen-doped carbon nanoring materials (such as...) Figure 11 ).

[0030] Comparative Example 1: (1) Weigh 100 mg g-C3N4 nanorings and disperse them in 100 mL of fresh Tris buffer solution. Add 300 mg of dopamine to the buffer solution and stir and polymerize at room temperature for 15 h to coat the surface of the solid product with polydopamine. The product obtained after coating is washed several times with deionized water. o Dry at C for 12 h.

[0031] (2) The product obtained in step (1) is calcined under an argon atmosphere at a temperature of 600°C. o C, with a time of 3 h, yielded nitrogen-doped carbon nanoring materials.

[0032] The materials obtained in Example 1 and Comparative Example 1 were used as anodes in sodium-ion batteries for electrochemical performance testing. Regarding long-cycle performance, the antimony single-atom-supported carbon nanoring material of Example 1 showed better performance at 5 A g / L. -1 At the current density, the specific capacity remained at 375.1 mAh g after 5000 cycles. -1 As a comparison, the nitrogen-doped carbon nanoring material in Comparative Example 1 had a specific capacity of only 147.2 mA hg after 5000 cycles. -1 Regarding rate performance, the antimony single-atom-supported carbon nanoring materials showed good performance at rates of 0.1, 0.2, 0.5, 1, 2, and 5 g. -1 At current densities of [values ​​missing], their discharge specific capacities are 450.2, 408.5, 381.5, 352.7, 332.8, and 317.2 mA hg, respectively. -1 The specific capacities of the nitrogen-doped carbon nanoring material in Comparative Example 1 were only 252.2, 209.1, 183.6, 168.9, and 155.6 mA hg. -1 Therefore, the cycle performance and rate performance of the material in Example 1, when used as a negative electrode material for sodium-ion batteries, are far superior to those of the comparative material, demonstrating that the antimony single-atom-supported carbon nanoring material has excellent sodium storage performance.

[0033] Example 2 This invention provides a method for preparing antimony single-atom-supported carbon nanoring materials, the method comprising: (1) Weigh 100 mg g-C3N4 nanorings, 180 mg urea, and 30 mg antimony acetate and disperse them in a mixed solution of 30 mL deionized water to form a dispersion. Transfer the dispersion to a high-pressure hydrothermal reactor for hydrothermal reaction at a temperature of 160 °C. o C, the reaction time was 4 h, and the solid product obtained from the hydrothermal reaction was washed three times with ethanol and water, respectively, and then subjected to 60 °C. o Dry at C for 24 hours.

[0034] (2) Weigh 120 mg of the solid prepared in step (1) and disperse it in 50 mL of freshly prepared Tris buffer solution. Add 200 mg of dopamine hydrochloride to the buffer solution and stir and polymerize at room temperature for 18 h to coat the surface of the solid product obtained in step (1) with polydopamine. Wash the product obtained after coating with deionized water several times. o Dry at C for 24 hours.

[0035] (3) The product obtained in step (2) is calcined under an argon atmosphere at a temperature of 650°C. o At time C, for 2 h, antimony single-atom-supported carbon nanoring materials were obtained.

[0036] The antimony single-atom-supported carbon nanoring material obtained in this embodiment was used as the anode of a sodium-ion battery for electrochemical performance testing. Regarding long-cycle performance, the antimony single-atom-supported carbon nanoring material of Example 2 showed good performance at 5 A g. -1 At the current density, the specific capacity remained at 208.9 mA hg after 5000 cycles. -1 Regarding rate performance, the antimony single-atom-supported carbon nanoring materials showed good performance at rates of 0.1, 0.2, 0.5, 1, 2, and 5 g. -1 At current densities of [values ​​missing], their discharge specific capacities are 342.2, 297.5, 268.6, 250.2, 225.7, and 202.8 mA hg, respectively. -1 This demonstrates that the antimony single-atom-supported carbon nanoring material obtained in this embodiment exhibits excellent electrochemical performance.

[0037] Example 3 This invention provides a method for preparing antimony single-atom-supported carbon nanoring materials, the method comprising: (1) Weigh 100 mg g-C3N4 nanorings, 720 mg urea, and 120 mg antimony acetate and disperse them in a mixed solution of 30 mL deionized water to form a dispersion. Transfer the dispersion to a high-pressure hydrothermal reactor for hydrothermal reaction at a temperature of 180 °C. o C, the reaction time was 2 h, and the solid product obtained from the hydrothermal reaction was washed three times with ethanol and water, respectively, at 70 °C. o Dry at C for 18 hours.

[0038] (2) Weigh 80 mg of the solid prepared in step (1) and disperse it in 150 mL of freshly prepared Tris buffer solution. Add 400 mg of dopamine hydrochloride to the buffer solution and stir and polymerize at room temperature for 12 h to coat the surface of the solid product obtained in step (1) with polydopamine. After coating, the product is washed multiple times with deionized water. o Dry at C for 18 h.

[0039] (3) The product obtained in step (2) is calcined under an argon atmosphere at a temperature of 700°C. o At time C, for 1 h, antimony single-atom-supported carbon nanoring materials were obtained.

[0040] The antimony single-atom-supported carbon nanoring material obtained in this embodiment was used as the anode of a sodium-ion battery for electrochemical performance testing. Regarding long-cycle performance, the antimony single-atom-supported carbon nanoring material of Example 3 achieved a performance of 5 A g / L at 5 A g / L. -1 At the current density, the specific capacity remained at 276.2 mA hg after 5000 cycles. -1 Regarding rate performance, the antimony single-atom-supported carbon nanoring materials showed good performance at rates of 0.1, 0.2, 0.5, 1, 2, and 5 g. -1 At current densities of [values ​​missing], their discharge specific capacities are 405.9, 373.1, 341.9, 321.4, 302.9, and 272.7 mA hg, respectively. -1 This demonstrates that the antimony single-atom-supported carbon nanoring material obtained in this embodiment exhibits excellent electrochemical performance.

[0041] The above-described embodiments are merely illustrative of the implementation methods of the present invention, but should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. A method for preparing antimony single-atom-supported carbon nanoring material, characterized in that, Antimony is uniformly dispersed in single-atom form and anchored on nitrogen-doped carbon nanorings through a reverse Oswald ripening process, and the antimony single atoms form an Sb-N4 coordination structure with the nitrogen in the nitrogen-doped carbon nanorings; including the following steps: Step 1: Prepare g-C3N4@Sb2O3 composite material; Using g-C3N4 nanorings as templates and antimony acetate as antimony source, a hydrothermal reaction was carried out by hydrothermal method to uniformly load Sb2O3 nanoparticles on the surface of g-C3N4 nanorings. After washing and drying, g-C3N4@Sb2O3 composite material was obtained. Steps to prepare g-C3N4@Sb2O3@PDA composite material; The g-C3N4@Sb2O3 composite material was dispersed in Tris buffer solution, and dopamine hydrochloride was added. The mixture was stirred at room temperature and pressure to allow dopamine to undergo in-situ self-polymerization on the surface of the composite material to form a polydopamine coating layer. After washing and drying, the g-C3N4@Sb2O3@PDA composite material was obtained. Steps to prepare SbSAs-CNR composite material; The g-C3N4@Sb2O3@PDA composite material was subjected to high-temperature carbonization under an inert atmosphere to form a hollow carbon nanoring structure, thus obtaining the antimony single-atom supported carbon nanoring material SbSAs-CNR.

2. The method for preparing an antimony single-atom supported carbon nanoring material according to claim 1, characterized in that, In step 1, the temperature of the hydrothermal reaction is 160-180°C. o C, the time is 2-4 hours.

3. The method for preparing an antimony single-atom supported carbon nanoring material according to claim 1, characterized in that, In step 1, the drying temperature is 60-80°C. o C, the time is 12-24 hours.

4. The method for preparing an antimony single-atom supported carbon nanoring material according to claim 1, characterized in that, In step 1, g-C3N4 nanorings and antimony acetate are simultaneously dispersed in deionized water to form a dispersion.

5. The method for preparing an antimony single-atom supported carbon nanoring material according to claim 1, characterized in that, In step 2, the mass ratio of the g-C3N4@Sb2O3 composite material to dopamine hydrochloride is 1:2-1:4; the stirring reaction time is 12-18 h.

6. The method for preparing an antimony single-atom supported carbon nanoring material according to claim 1, characterized in that, In step 2, 80-120g of g-C3N4@Sb2O3 composite material is added to every 50-150mL of Tris buffer solution.

7. The method for preparing an antimony single-atom supported carbon nanoring material according to claim 1, characterized in that, In step 3, the high-temperature carbonization temperature is 600-700°C. o C, carbonization time is 1-3 h.

8. The method for preparing an antimony single-atom supported carbon nanoring material according to claim 1, characterized in that, In step 3, the inert gas is nitrogen or argon.

9. A carbon nanoring material supported on antimony single atoms, characterized in that, The carbon nanoring material supported by antimony single atoms is prepared by any of the preparation methods described in claims 1-8, wherein the antimony single atoms are anchored to the nitrogen-doped carbon nanorings through Sb-N4 coordination chemical bonds and are uniformly dispersed.

10. An application of the antimony single-atom supported carbon nanoring material according to claim 9, characterized in that, The antimony single-atom-supported carbon nanoring material is used as the negative electrode active material of SIBs in the field of energy storage.

Images