A multi-element metal sulfide and a low-temperature synthesis method and application thereof

Abstract

The application discloses a kind of multinary metal sulfide and its low-temperature synthesis method and application, it is related to metal sulfide material technical field, after being mixed evenly with metal source powder and sulfur elemental powder, it is carried out ball milling reaction at room temperature, and multinary metal sulfide is obtained;The application innovatively takes room temperature as reaction temperature, with the mechanical shear force generated in the ball milling process, drive multiple-component metal source and sulfur source to occur in-situ solid-phase co-reaction, without high temperature, high pressure and organic solvent, so as to break through the technical limitation of traditional method;And by adjusting ball milling parameters, realize the continuous controllable synthesis of multinary metal sulfide from amorphous highly disordered state to high crystalline state, provide a new technical path for efficient controllable preparation and industrial application of multinary metal sulfide.

Description

Technical Field

[0001] This invention relates to the field of metal sulfide materials technology, specifically to a multi-metal sulfide and its low-temperature synthesis method and application. Background Technology

[0002] Multi-component metal sulfides, as an important class of inorganic functional materials, possess tunable electronic structures, excellent redox activity, high ionic conductivity, and chemical stability, and are widely used in various fields such as electrochemical energy storage, electrocatalysis, photoelectric conversion, thermoelectric materials, and environmental remediation. Among them, high-entropy metal sulfides, as novel multi-principal metal sulfide materials, have broken through the performance bottlenecks of traditional binary / ternary sulfides by virtue of their single-solid-phase stable structure, continuous tunability of composition, lattice distortion, and synergistic effect of multiple active sites brought about by the high-entropy effect. They have shown great potential for application in cutting-edge fields such as energy storage, electrocatalysis, thermoelectric conversion, and photoelectric detection, and have become a research hotspot in the field of materials in recent years.

[0003] Currently, the mainstream technical routes for the synthesis and preparation of multi-metal sulfides, especially high-entropy metal sulfides, are mainly high-temperature solid-state methods and solvothermal methods, supplemented by chemical vapor deposition, pulsed laser deposition, sol-gel methods, and other techniques. Among them, the high-temperature solid-state method is the most traditional process for preparing metal sulfide materials. It usually involves mixing the metal source and the sulfur source in a stoichiometric ratio and then carrying out a long-term sulfidation reaction at a high temperature of 500°C or even 1000°C. While this method can produce highly crystalline metal sulfide products, it suffers from several insurmountable technical drawbacks: First, the high-temperature reaction consumes extremely high energy and has a long process cycle. Furthermore, the sulfur source is highly volatile at high temperatures, leading not only to uncontrolled sulfur-metal stoichiometry and impurity phase formation but also to the release of toxic sulfur-containing gases, posing serious environmental and safety risks. Second, during the high-temperature reaction, grains are prone to excessive growth and agglomeration, making it difficult to prepare powder materials with uniform particle size. Simultaneously, multi-principal metal components are prone to phase separation and component segregation at high temperatures, making it impossible to achieve atomic-level uniform solid solution of multiple metal elements and synthesize high-quality high-entropy sulfides. Third, the crystallization behavior during the high-temperature reaction is uncontrollable, making it impossible to precisely control the crystallinity of the product. It is difficult to prepare a series of products ranging from amorphous, highly disordered phases to highly crystalline phases in the same system, thus failing to meet the differentiated requirements for material crystallinity in different application scenarios.

[0004] The solvothermal method is a commonly used method for preparing multi-component metal sulfides in the laboratory. It can achieve the synthesis of metal sulfides in a mesotemperature environment of 120~250℃, which reduces the reaction temperature to some extent. However, this method still has significant technical shortcomings: First, the reaction still requires external heating and must be carried out in a high-pressure reactor, which has high pressure resistance requirements, poses safety hazards, and makes large-scale production extremely difficult. Second, the reaction requires the use of a large amount of organic solvents and additives, which not only increases production costs but also generates a large amount of waste liquid, putting great pressure on the environment. At the same time, the post-processing of the product is complex, and solvent and impurity residues are likely to remain, affecting the purity and performance stability of the material. Third, the precipitation and reaction kinetics of multi-component metal ions in the liquid phase system are significantly different, which easily leads to component segregation and phase separation, making it difficult to achieve uniform synthesis of multi-principal high-entropy metal sulfides. In addition, the crystallinity control window of the product is narrow, making it impossible to achieve continuous and controllable synthesis from amorphous to highly crystalline states. Fourth, the batch stability of the reaction is poor. Small fluctuations in process parameters can lead to significant differences in product performance, making it difficult to achieve stable industrial production. Other techniques, such as chemical vapor deposition and pulsed laser deposition, can only prepare thin-film metal sulfide materials and cannot prepare powder materials. Moreover, the equipment is expensive and the production capacity is extremely low, which cannot meet the needs of large-scale applications. The sol-gel method has problems such as complicated process, long cycle, easy product agglomeration, and difficulty in controlling sulfur stoichiometry, which limits its application scope.

[0005] To address the shortcomings of the aforementioned high-temperature and liquid-phase processes, existing technologies have attempted to synthesize metal sulfide materials using mechanochemical methods. However, these technologies still face significant technical bottlenecks: First, current mechanochemical synthesis processes still require medium-to-high temperature heating or high-temperature annealing after ball milling to obtain crystalline products, failing to completely eliminate high-temperature dependence and fundamentally solve the problems of high energy consumption and sulfur source volatilization. Second, existing processes can only synthesize specific binary and ternary metal sulfides, with a narrow range of compatible metal elements, making it impossible to synthesize fourth to sixth metal sulfides. The co-reaction of multiple transition metals and main group metals in the periodic series makes it difficult to synthesize high-quality multi-principal high-entropy metal sulfides; thirdly, the solid-phase reaction process cannot be precisely controlled by mechanical force, making it difficult to achieve continuous and controllable synthesis of product crystallinity, and it is impossible to simultaneously prepare amorphous, highly disordered phases to highly crystalline phases of multi-component metal sulfides in a single system at room temperature; fourthly, some processes require the addition of process control agents, dispersants and other auxiliary materials, which can easily introduce impurities, affect product purity, and have poor process parameter adaptability and insufficient batch stability, making it difficult to achieve industrial scale-up.

[0006] In summary, existing technologies for synthesizing multi-metal sulfides generally suffer from core technological bottlenecks, including high temperature dependence, high energy consumption, complex processes, high environmental risks, narrow component compatibility range, poor product uniformity, inability to continuously and controllably regulate crystallinity, and difficulty in large-scale production. These bottlenecks severely restrict the performance optimization and industrial application of multi-metal sulfides, especially high-entropy metal sulfides. Therefore, developing a room-temperature, low-temperature, simple, environmentally friendly, highly controllable, widely compatible metal component method that is easy to scale up for production, and capable of continuous and controllable synthesis of products from amorphous, highly disordered phases to highly crystalline phases, has become an urgent technical problem to be solved in this field. Summary of the Invention

[0007] The technical problem this invention aims to solve is to provide a low-temperature synthesis method for multi-metal sulfides. This innovative method uses room temperature as the reaction temperature and leverages the mechanical shear force generated during ball milling to drive an in-situ solid-phase co-reaction between a multi-component metal source and a sulfur source. It eliminates the need for high temperature, high pressure, and organic solvents, thus overcoming the technical limitations of traditional methods. Furthermore, by adjusting ball milling parameters, the continuous and controllable synthesis of multi-metal sulfides from an amorphous, highly disordered state to a highly crystalline state is achieved. This method is applicable to various transition metals and main group metals from the fourth to sixth periods, yielding powder materials with excellent uniformity. The entire process is simple, environmentally friendly, and energy-efficient, effectively addressing the core shortcomings of existing technologies. It provides a novel technical path for the efficient and controllable preparation and industrial application of multi-metal sulfides, demonstrating significant innovation and industrial application value.

[0008] The technical problem to be solved by this invention is achieved by the following technical solution: One objective of this invention is to provide a low-temperature synthesis method for multi-metal sulfides, which involves uniformly mixing metal source powder and elemental sulfur powder and then performing a ball milling reaction to obtain multi-metal sulfides.

[0009] Furthermore, the metal source is at least one of an elemental metal or a metal sulfide.

[0010] Furthermore, the metal source is at least one of a transition metal and a main group metal. Even further, the transition metal is a transition metal from the fourth to the sixth period, including but not limited to at least one of Ti, V, Mn, Fe, Co, Cu, Nb, Mo, and W; the main group metal is a main group metal from the second to the sixth period, including but not limited to at least one of Sn, Sb, and Bi.

[0011] Furthermore, the ball milling reaction is carried out at room temperature. No heating is required, the operation is simple, and energy consumption is low.

[0012] Furthermore, the ball milling reaction is carried out in a protective atmosphere free of water and oxygen. Even further, the protective atmosphere is argon.

[0013] Furthermore, the ball-to-material mass ratio of the ball milling reaction is (10~240):1.

[0014] Furthermore, the rotation speed of the ball milling reaction is 300~1200 rpm.

[0015] Furthermore, the total effective operating time of the ball milling reaction is 20-120 hours. In some specific embodiments, the ball milling reaction adopts an intermittent operation mode, and the ratio of the ball milling operation time to the intermittent shutdown rest time within a single operating cycle is 9:1 to 1:1.

[0016] The second objective of this invention is to provide a low-temperature synthesis method for preparing multi-metal sulfides.

[0017] Furthermore, the total molar ratio of sulfur to metal in the multi-metal sulfide is (1~2):1.

[0018] Furthermore, the size of the multi-metal sulfide is 1~5 μm.

[0019] Furthermore, the crystallinity of the multi-metal sulfide is continuously regulated between an amorphous, highly disordered state and a highly crystalline state.

[0020] A third objective of this invention is to provide the application of the aforementioned multi-metal sulfide in batteries. Specifically, the multi-metal sulfide is used as an electrode material.

[0021] The fourth objective of this invention is to provide a potassium-ion battery using the aforementioned multi-metal sulfide as the negative electrode material.

[0022] The fifth objective of this invention is to provide a lithium-carbon dioxide battery using the aforementioned multi-metal sulfide as the positive electrode material.

[0023] In a room-temperature solid-state reaction system, this invention utilizes the mechanical shear force generated during ball milling to regulate the solid-state co-reaction process of multi-component metal sources and sulfur sources, thereby achieving the controllable synthesis of multi-component sulfides from an amorphous, highly disordered phase to a highly crystalline phase.

[0024] The beneficial effects of this invention are: (1) The reaction conditions are mild, and the entire process is synthesized at room temperature and normal pressure. There is no need for high-temperature calcination and high-pressure environment, which greatly reduces energy consumption and process threshold. The entire process is solvent-free and surfactant-free, green and environmentally friendly with no waste liquid, no organic impurities, and no need for complicated purification processes.

[0025] (2) It has a wide range of metal components and can be compatible with a variety of transition and main group metal elements from the fourth to the sixth period. It breaks the reaction kinetic barrier of different metals, realizes multi-component synchronous solid-phase co-reaction, effectively avoids component segregation and phase separation problems, and can stably prepare single solid-phase multi-element sulfides with atomic-level uniform solid solution of multiple metals.

[0026] (3) By adjusting the ball milling process parameters, the crystallinity of the product can be continuously and precisely controlled from the amorphous and highly disordered state to the highly crystalline state, which can meet the differentiated needs of multiple scenarios. The core process only includes two steps: premixing and room temperature ball milling. There are no organic solvents or auxiliary materials added. The batch stability is good, and it is fully compatible with existing industrial powder equipment, making it easy to scale up. Attached Figure Description

[0027] Figure 1 The X-ray diffraction (XRD) patterns of the FeMnCuMoSnWS2 samples prepared in Examples 1-6 of this invention are shown below. Figure 2 XRD patterns (ab) of FeMnCuMoSnWS2 samples prepared in Examples 7-10 of the present invention; XRD patterns (c) of FeMnCuMoSnWS samples prepared in Examples 11-12; and XRD patterns (d) of FeSnTiNbMoWS and FeSnTiNbMoWS2 samples prepared in Examples 13-14. Figure 3 XRD patterns (a) of MnMoS2 samples prepared in Examples 15-16 of this invention; XRD patterns (b) of CuSnS2 samples prepared in Examples 17-18; XRD patterns (c) of VS4 samples prepared in Example 19; and XRD patterns (d) of NbS3 samples prepared in Example 20. Figure 4 Low-resolution and high-resolution transmission electron microscopy (TEM) images of the FeMnCuMoSnWS2 sample prepared in Example 6 of this invention; Figure 5 This is an elemental distribution diagram of the FeMnCuMoSnWS2 sample prepared in Example 6 of the present invention; Figure 6 These are low-resolution and high-resolution TEM images of the FeMnCuMoSnWS sample prepared in Example 12 of this invention; Figure 7 The elemental distribution diagram of the FeMnCuMoSnWS sample prepared in Example 12 of this invention; Figure 8 To illustrate the lithium-carbon dioxide batteries assembled using the FeMnCuMoSnWS2 sample prepared in Example 6 of this invention as the cathode material at different current densities (20~200 μA·cm⁻¹) -2Voltage-time relationship curve under ( ); Figure 9 To test potassium-ion batteries assembled using the amorphous VS4 sample prepared in Example 19 of this invention and the crystalline VS4 sample prepared in Comparative Example 1 as negative electrode materials at a current density of 0.1 mA·g -1 The second charge-discharge curve below. Detailed Implementation

[0028] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific embodiments and illustrations.

[0029] Example 1: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle, followed by a transfer to a zirconia ball mill jar. The ball-to-powder mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 20 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0030] Example 2: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-powder mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 40 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0031] Example 3: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-powder mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 60 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0032] Example 4: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle, followed by a zirconia ball mill jar with a ball-to-material mass ratio of 20:1. The mixture was ball-milled at 500 rpm for 80 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm. A powdered product was obtained.

[0033] Example 5: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle, followed by a transfer to a zirconia ball mill jar. The ball-to-material mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 100 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0034] Example 6: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-material mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 120 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0035] Example 7: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, Mo, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle, followed by a transfer to a zirconia ball mill jar. The ball-to-material mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 60 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0036] Example 8: Synthesis of FeMnCuMoSnWS2 At room temperature, FeS2, Sn, WS2, Mo, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-material mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 120 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0037] Example 9: Synthesis of FeMnCuMoSnWS2 At room temperature, Fe, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-powder mass ratio was 20:1. The mixture was ball-milled at 500 rpm for 60 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0038] Example 10: Synthesis of FeMnCuMoSnWS2 At room temperature, Fe, Sn, WS2, MoS2, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle, followed by a transfer to a zirconia ball mill jar. The ball-to-material mass ratio was 20:1. The mixture was ball-milled at 800 rpm for 60 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0039] Example 11: Synthesis of FeMnCuMoSnWS At room temperature, Fe, Sn, WS2, Mo, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:1 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-powder mass ratio was 20:1. The mixture was ball-milled at 800 rpm for 60 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0040] Example 12: Synthesis of FeMnCuMoSnWS At room temperature, Fe, Sn, WS2, Mo, MnS, and CuS powders were weighed and placed in an agate mortar with elemental sulfur powder, according to a total molar ratio of 1:1 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-powder mass ratio was 40:1. The mixture was ball-milled at 800 rpm for 120 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeMnCuMoSnWS sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0041] Example 13: Synthesis of FeSnTiNbMoWS At room temperature, Fe, Sn, W, Mo, Ti, and Nb powders were weighed and mixed with elemental sulfur powder in an agate mortar according to a total molar ratio of 1:1 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-material mass ratio was 40:1. The mixture was ball-milled at 800 rpm for 60 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeSnTiNbMoWS sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0042] Example 14: Synthesis of FeSnTiNbMoWS2 At room temperature, Fe, Sn, W, Mo, Ti, and Nb powders were weighed and mixed with elemental sulfur powder in an agate mortar according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1:1:1:1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-material mass ratio was 40:1. The mixture was ball-milled at 800 rpm for 60 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered FeSnTiNbMoWS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0043] Example 15: Synthesis of MnMoS2 At room temperature, MoS2, MnS powder, and elemental sulfur powder were weighed and placed in an agate mortar according to a total molar ratio of metal element to sulfur of 1:2 and a molar ratio of each metal element of 1:1. After hand-grinding with an agate pestle for 10 min, the powder was added to a zirconia ball mill jar at a ball-to-powder mass ratio of 40:1. The milling was carried out at 500 rpm for 20 h, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered MnMoS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0044] Example 16: Synthesis of MnMoS2 At room temperature, MoS2, MnS powder, and elemental sulfur powder were weighed and placed in an agate mortar according to a total molar ratio of metal element to sulfur of 1:2 and a molar ratio of each metal element of 1:1. After hand-grinding with an agate pestle for 10 min, the powder was added to a zirconia ball mill jar at a ball-to-powder mass ratio of 40:1. The milling was carried out at 500 rpm for 100 h, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered MnMoS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0045] Example 17: Synthesis of CuSnS2 At room temperature, CuS and Sn powders, along with elemental sulfur powder, were weighed and placed in an agate mortar according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1 for each metal element. The mixture was then hand-ground for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-powder mass ratio was 40:1. The mixture was ball-milled at 500 rpm for 20 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered CuSnS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0046] Example 18: Synthesis of CuSnS2 At room temperature, CuS and Sn powders, along with elemental sulfur powder, were weighed and placed in an agate mortar according to a total molar ratio of 1:2 for the metal elements and a molar ratio of 1:1 for each metal element. The mixture was then hand-milled for 10 minutes using an agate pestle before being transferred to a zirconia ball mill jar. The ball-to-powder mass ratio was 40:1. The milling was carried out at 500 rpm for 100 hours, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered CuSnS2 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0047] Example 19: Synthesis of VS4 At room temperature, V2S3 powder and elemental sulfur powder were weighed in an agate mortar at a molar ratio of 1:5 and hand-ground for 10 min using an agate grinding pestle. The mixture was then added to a zirconia ball mill jar with a ball-to-powder mass ratio of 40:1. The mixture was ball-milled at 500 rpm for 60 h, with a milling time to intermittent rest time ratio of 9:1, yielding a powdered VS4 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0048] Example 20: Synthesis of NbS3 At room temperature, NbS2 powder and elemental sulfur powder were weighed in an agate mortar at a molar ratio of 1:1 and hand-ground for 10 min using an agate pestle. The mixture was then added to a zirconia ball mill jar at a ball-to-powder mass ratio of 40:1 and ball-milled at 800 rpm for 60 h. The ratio of milling time to intermittent rest periods was 9:1, yielding a powdered NbS3 sample. All operations were performed under argon protection, ensuring that the moisture pressure and oxygen partial pressure were both less than 1 ppm.

[0049] Figure 1 The images show the XRD patterns of the FeMnCuMoSnWS2 samples prepared in Examples 1-6. Figure 1 It can be clearly observed that the diffraction peaks of the product gradually evolve with the gradient control of the ball milling reaction parameters, which intuitively proves that the present invention can achieve continuous, precise and controllable synthesis of multi-component sulfides from amorphous and highly disordered phases to highly crystalline phases through room temperature ball milling.

[0050] Figure 2 XRD patterns (ab) of FeMnCuMoSnWS2 samples prepared in Examples 7-10; XRD patterns (c) of FeMnCuMoSnWS samples prepared in Examples 11-12; and XRD patterns (d) of FeSnTiNbMoWS and FeSnTiNbMoWS2 samples prepared in Examples 13-14. Figure 3 The images show the XRD patterns (a) of the MnMoS2 samples prepared in Examples 15-16 of this invention; (b) of the CuSnS2 samples prepared in Examples 17-18; (c) of the VS4 sample prepared in Example 19; and (d) of the NbS3 sample prepared in Example 20. Figure 2 and Figure 3 It is evident that, for multi-component sulfide systems with different stoichiometric ratios and different combinations of principal metals, the synthesis method provided by this invention can achieve gradient adjustment of the crystallinity of the products in different systems through process control, fully demonstrating the excellent universality of the method of this invention.

[0051] Figure 4 These are low-resolution and high-resolution TEM images of the FeMnCuMoSnWS2 sample prepared in Example 6. Figure 6 These are low-resolution and high-resolution TEM images of the FeMnCuMoSnWS sample prepared in Example 12 of this invention. From... Figure 4 and Figure 6 As can be seen, the low-resolution TEM images show that the products are all plate-like structures with similar sizes; the high-resolution TEM images clearly show the regular lattice fringes of the product in Example 6, confirming the high crystallinity of the product; and the highly disordered lattice fringes of the product in Example 12 are observed, corresponding to the high degree of disorder in the crystal phase of this product. This proves the high tunability of the crystal phase of the multi-metal sulfide synthesized by this method.

[0052] Figure 5 The elemental distribution diagram is shown for the FeMnCuMoSnWS2 sample prepared in Example 6. Figure 7 This is the elemental distribution diagram of the FeMnCuMoSnWS sample prepared in Example 12 of this invention. From... Figure 5 and Figure 7 As can be seen, all constituent elements are uniformly distributed, which directly demonstrates the successful construction of a stable single-phase multi-component solid solution structure.

[0053] Using FeMnCuMoSnWS2 prepared in Example 6 as the positive electrode material, the positive electrode material was mixed with conductive carbon black (SuperP) and binder polyvinylidene fluoride (PVDF) in a mass ratio of 7:2:1, and ethanol was added dropwise to prepare a uniform slurry. The slurry was uniformly drop-coated onto a square carbon cloth (1 cm in diameter) and vacuum dried at 60 °C for 12 h to obtain the positive electrode sheet. Using a lithium sheet as the negative electrode sheet, a modified 2032 coin cell (with an open positive electrode shell) was assembled in an argon-filled glove box. Whatman glass fiber D was used as the separator, and the electrolyte was a 1 mol / L lithium bis(trifluoromethanesulfonyl)imide solution (prepared from dimethyl sulfoxide). The Newway testing system was used as the testing platform. The assembled 2032 coin cell was placed in a blue-capped bottle with a connecting wire for testing. Carbon dioxide was introduced into the bottle, and after standing for 12 h, electrochemical performance was tested. The voltage window was 1~5 V.

[0054] Figure 8 Lithium-carbon dioxide batteries assembled using the FeMnCuMoSnWS2 sample prepared in Example 6 as the cathode material were tested at different current densities (20~200 μA·cm). -2 The voltage-time relationship curve under ( ). From Figure 8 It can be seen that in the range of 20~200 μA·cm -2Within the current density range, the polarization potential of the lithium-carbon dioxide battery remained stable after cycling at progressively increasing current densities and then returning to low current density conditions, indicating that the battery possesses excellent electrochemical reversibility. Meanwhile, the charging potential of the battery at each tested current density was significantly lower than 4.0 V, which fully demonstrates its excellent catalytic reaction kinetics and electrocatalytic activity.

[0055] Comparative Example 1: Synthesis of Crystal VS4 Vanadium and sulfur powders were weighed in a molar ratio of 1:4, mixed thoroughly, and then packed into a quartz ampoule. The ampoule was then evacuated until the residual pressure reached 10. -2 torr. Seal the ampoule, heat to 400°C, and store at this temperature for ten days. Cool to room temperature to obtain crystalline VS4 samples.

[0056] Using the amorphous VS4 sample prepared in Example 19 and the crystalline VS4 sample prepared in Comparative Example 1 as negative electrode materials, the negative electrode materials were mixed with the conductive agent Super P and the binder PVDF in a mass ratio of 7:2:1, and then thoroughly mixed with N-methylpyrrolidone to form a uniform slurry. The slurry was uniformly coated onto copper foil and vacuum dried at 60°C for 12 h. After cutting, circular negative electrode sheets with a diameter of 12 mm were obtained. Using potassium metal sheets as negative electrode sheets, conventional 2032 coin cells were assembled in an argon-filled glove box, using Whatman glass fiber D as the separator, and the electrolyte as a 1 mol / L potassium bis(trifluoromethanesulfonyl)imide solution (prepared from diethylene glycol diethyl ether). The Xinwei testing system was used as the testing platform, and the electrochemical performance was tested after the battery was placed for 12 h, with a voltage window of 0.1~3 V.

[0057] Figure 9 To test potassium-ion batteries assembled using the amorphous VS4 sample prepared in Example 19 and the crystalline VS4 sample prepared in Comparative Example 1 as negative electrode materials at a current density of 0.1 mA·g -1 The second charge-discharge curve below. (From...) Figure 9 It can be seen that, under the same test conditions, compared with crystalline VS4, the amorphous VS4 prepared in this invention can significantly improve the discharge capacity of potassium-ion batteries when used as the negative electrode material, which indicates that the material has excellent potassium-ion storage capacity and energy storage performance.

[0058] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A low-temperature synthesis method for multi-metal sulfides, characterized in that: After the metal source powder and elemental sulfur powder are mixed evenly, they are subjected to ball milling to obtain multi-metal sulfides.

2. The low-temperature synthesis method according to claim 1, characterized in that: The metal source is at least one of elemental metal and metal sulfide.

3. The low-temperature synthesis method according to claim 1, characterized in that: The metal source is at least one of transition metals and main group metals; Preferably, the transition metal is a transition metal from the fourth to the sixth period, selected from at least one of Ti, V, Mn, Fe, Co, Cu, Nb, Mo, and W; Preferably, the main group metal is a main group metal from the second to the sixth period, selected from at least one of Sn, Sb, and Bi.

4. The low-temperature synthesis method according to claim 1, characterized in that: The ball milling reaction was carried out at room temperature; Preferably, the ball milling reaction is carried out in a protective atmosphere free of water and oxygen; Preferably, the ball-to-material mass ratio in the ball milling reaction is (10~240):1; Preferably, the ball milling reaction is carried out at a speed of 300~1200 rpm; Preferably, the total effective operating time of the ball milling reaction is 20-120 h; Preferably, the ball milling reaction adopts an intermittent operation mode, and the ratio of the ball mill operation time to the intermittent shutdown rest time in a single operation cycle is 9:1 to 1:

1.

5. Multimetallic sulfides prepared by the low-temperature synthesis method according to any one of claims 1 to 4.

6. The multi-metal sulfide according to claim 5, characterized in that: The total molar ratio of sulfur to metal elements in the multi-metal sulfide is (1~2):

1.

7. The multi-metal sulfide according to claim 5, characterized in that: The size of the multi-metal sulfide is 1~5 μm; Preferably, the crystallinity of the multi-metal sulfide is continuously controlled between an amorphous, highly disordered state and a highly crystalline state.

8. The application of the multi-metal sulfide according to any one of claims 5 to 7 in batteries.

9. A potassium-ion battery, characterized in that: The multi-metal sulfide described in any one of claims 5 to 7 is used as the negative electrode material.

10. A lithium-carbon dioxide battery, characterized in that: The multi-metal sulfide described in any one of claims 5 to 7 is used as the cathode material.

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