Lattice-confined M 0.67 NS 2-x Cl x Materials, methods of making, uses, and sodium-ion batteries

Abstract

The application discloses a lattice-restricted M 0.67 NS 2‑x Cl x material, a preparation method and application thereof and a sodium ion battery. The material belongs to a hexagonal system and has a P63 / mcm space group; M is Sb and / or Bi, N is Ta, and 0<=x<0.5; the material is stacked by a plurality of NS 6‑y Cl y single layers; the single layer of the NS 6‑y Cl y includes N atoms combined with S atoms and Cl atoms to form a side-shared NS 6‑y Cl y prism layer; M atoms are intercalated into a sandwich of adjacent NS 6‑y Cl y prism layers; and each M atom is combined with one S atom or Cl atom in each of the two adjacent NS 6‑y Cl y prism layers to form a linear geometric structure, and 0<=y<0.5. The material prepared by the application effectively alleviates the volume expansion of M atoms in the alloying process and exhibits excellent electrochemical performance when applied to a sodium ion battery.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of lattice-restricted M 0.67 NS 2-x Cl x Material, preparation method, application and sodium ion battery. BACKGROUND

[0002] The rapid development of portable electronic products and grid energy storage has driven the increasing demand for electrode materials with high energy density, low cost and higher safety performance. Given the scarcity of lithium resources used by lithium-ion batteries, sodium-ion batteries (SIBs) have become an alternative that can effectively reduce manufacturing costs due to their abundant sodium resources. However, compared to Li + , the ion size and relative atomic mass of Na + are larger, and the Na + diffusion kinetics is slower, exacerbating the energy-power trade-off problem. Therefore, it is crucial to rationally design electrode materials that have both observable Na + storage capacity and fast charging characteristics.

[0003] For anode materials of SIBs, traditional hard carbon faces the risk of high-speed formation of sodium dendrites due to its extremely low sodium intercalation potential. Alloy-type anodes have appropriate reaction potentials and high theoretical capacities, making them ideal candidates. Among them, bismuth (Bi) and Sb are more conducive to the rapid diffusion of ions due to their unique flexural layer structure and large interlayer spacing, and are very suitable for large-scale fast energy storage systems due to their high theoretical capacity and eco-friendly characteristics. However, under high current density conditions, Bi and Sb will undergo significant volume changes during repeated alloying / de-alloying, which will lead to electrode pulverization, hindering the transfer and diffusion of Na + , resulting in performance degradation during the cycle process. Therefore, the key to improving the fast charging capability of Bi-based anodes lies in alleviating the volume expansion of Bi during charging / discharging and constructing a diffusion channel that facilitates the rapid passage of Na + . SUMMARY

[0004] The technical problem solved by the present application is to overcome the defects in the prior art that Bi-based anodes undergo severe volume expansion during charging / discharging, resulting in a decrease in electrochemical performance during the cycle process, and to provide a kind of lattice-restricted M 0.67 NS 2-x Cl x Material, preparation method, application and sodium ion battery. The lattice-restricted M 0.67 NS 2-x Cl xThe material effectively alleviates the volume expansion of M atoms during the alloying process and exhibits excellent electrochemical performance when applied in sodium-ion batteries.

[0005] Conventional M-based (Sb and / or Bi) alloying reactions usually result in relatively large M lattice expansion and phase transition during alloying / de-alloying, leading to structural damage during cycling. This invention provides a lattice-restricted local alloying strategy to achieve ultrafast and stable sodium storage (N is Ta) by intercalating M atoms into the interlayer of N-SCl triangular prisms. 0.67 NS 2-x Cl x In the NS, N atoms are combined with S atoms and Cl atoms (the sum of the number of S atoms and Cl atoms combined with N atoms is 6) to form a side-shared NS 6-y Cl y prism, and each M atom is connected to two adjacent NS 6-y Cl y One S atom or Cl atom in each prism layer combines to form a linear geometric structure. During the alloying process (sodiumization), as the M-Na bond appears, the MS bond or M-Cl bond gradually breaks, thus forming Na x M 0.67 NS 2-x Cl x In the subsequent dealloying process (de-sodiumization), Na + Movement, accompanied by the reconstruction of MS bond, M-Cl bond and initial M 0.67 NS 2-x Cl x The weak MS coordination bond or MC bond is easier to break and rebuild, while the rigid NS 2-x Cl x The binding effect of the framework limits the volume expansion of M during the sodiumization process. This "sandwich structure" provides a functional design for efficient electrochemical reactions, in which M acts as an alloying center and NS 2-x Cl x As a rigid framework and fast ion / electron transport channel, the confinement effect and better structural stability will effectively reduce the structural collapse and improve the high-rate capability and cycling stability of SIBs.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] The present invention provides a lattice-limited M 0.67 NS 2-x Cl x The material belongs to the hexagonal system and has a space group of P63 / mcm;

[0008] M is Sb and / or Bi, N is Ta, 0≤x<0.5;

[0009] By multiple NS 6-y Cl y The single layer stacked, the NS 6-y Cl y The single layer includes N atoms combined with S atoms and Cl atoms to form side-shared NS 6-y Cl y Prism layer, the sum of the number of the S atoms and the Cl atoms bonded to the N atoms is 6, and the M atoms are intercalated to the adjacent NS 6-y Cl y In the interlayer of the prism layer, each M atom is bonded to two adjacent NS 6-y Cl y One S atom or Cl atom in each prism layer combines to form a linear geometric structure, 0≤y<0.5.

[0010] In the present invention, preferably, 0<x<0.5, such as 0.1, 0.2 or 0.3, more preferably, 0.15<x<0.4.

[0011] In the present invention, the lattice-restricted M 0.67 NS 2-x Cl x The material can be Bi 0.67 TaS2、Bi 0.67 TaS 1.7 Cl 0.3 Or Bi 0.67 TaS 1.9 Cl 0.1 .

[0012] In the present invention, the lattice-restricted M 0.67 NS 2-x Cl x The material is Bi 0.67 In the case of TaS2, using Cu Kα radiation, its X-ray powder diffraction shows characteristic diffraction peaks at diffraction angles 2θ of 10.14°, 17.96°, 20.36°, 31.36°, 33.04°, 41.40°, 44.49°, 55.82° and 60.05°.

[0013] The present invention also provides a lattice-restricted M 0.67 NS 2-x Cl x The preparation method of the material comprises the following steps: subjecting the raw materials of "S source and / or Cl source", M source and N source to a high temperature solid phase reaction in a vacuum environment to obtain the lattice-restricted M 0.67 NS 2-x Cl xMaterial;

[0014] The high-temperature solid-phase reaction is performed at a temperature of 800-1200 ℃ for 20-48 h.

[0015] In the present application, the N source can be N element, N-containing sulfide or N-containing chloride, such as Ta, TaS2 or TaCl2. The M source can be M element, M-containing sulfide or M-containing chloride, such as Bi, Sb, BiS2 or SbCl3. The S source can be S element or S-containing compound, such as S, TaS2 or BiS2. The Cl source can be N-containing chloride or M-containing chloride, such as TaCl2. As long as the molar ratio of M atoms, N atoms, S atoms and Cl atoms meets the preset requirement, such as 0.67:1:2-x:x (i.e. all raw materials are completely reacted), 0≤x<0.5. It can be understood that the M source and the N source can also be the S source or the Cl source.

[0016] In one embodiment, the lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 TaS2, the M source is Bi powder, the N source is Ta powder, the S source is S powder, and the molar ratio of the Bi powder, the Ta powder and the S powder is 0.67:1:2.

[0017] In one embodiment, the lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 TaS 1.7 Cl 0.3 The M source is Sb powder, the N source and the Cl source are Ta powder and TaCl2, the S source is S powder, and the molar ratio of the Sb powder, the Ta powder, the TaCl2 and the S powder is 0.67:0.85:0.15:1.7.

[0018] In one embodiment, the lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 TaS 1.9 Cl 0.1 The M source is BiS2, the N source and the Cl source are TaCl2 and Ta powder, the S source is S powder, and the molar ratio of the BiS2, the Ta powder, the TaCl2 and the S powder is 0.67:0.95:0.05:0.56.

[0019] In the present application, the rate of temperature rise to the temperature of the high-temperature solid-phase reaction can be 1-10℃ / min, for example 3℃ / min.

[0020] In the present application, the temperature of the high-temperature solid-phase reaction is preferably 800-1000℃, for example 880℃.

[0021] In the present application, the time of the high-temperature solid-phase reaction is preferably 20-30h, for example 24h.

[0022] In the present application, after the high-temperature solid-phase reaction, natural cooling to room temperature is generally required according to the prior art.

[0023] In the present application, preferably, the lattice-confined M 0.67 NS 2-x Cl x The preparation method of the material comprises the following steps: grinding and mixing an S source and / or a Cl source, an M source and an N source to obtain a raw material powder; placing the raw material powder in a reaction tube, and performing a high-temperature solid-phase reaction on the reaction tube after vacuumizing and sealing the reaction tube, to obtain the lattice-confined M 0.67 NS 2-x Cl x material.

[0024] After vacuumizing, the vacuum degree of the reaction tube is less than or equal to 10 -3 Pa.

[0025] Preferably, the reaction tube is a quartz tube.

[0026] The present application also provides a use of the lattice-confined M 0.67 NS 2-x Cl x material in a sodium-ion battery.

[0027] The present application also provides a sodium-ion battery comprising a positive electrode, a negative electrode, an electrolyte and a separator, wherein the negative electrode comprises the lattice-confined M 0.67 NS 2-x Cl x material as described above.

[0028] In the present application, the positive electrode preferably comprises a positive electrode current collector and a positive electrode active material coated on the positive electrode current collector.

[0029] Preferably, the positive electrode active material is a layered transition metal oxide, a Prussian compound or a polyanion compound (for example Na3V2(PO4)3).

[0030] Preferably, the positive electrode current collector can be conventional in the art, and is generally an aluminum foil.

[0031] In the present application, the negative electrode preferably comprises a negative electrode current collector and a negative electrode active material coated on the negative electrode current collector, and the negative electrode active material comprises the lattice-restricted bismuth-based material as described above.

[0032] The negative electrode current collector can be conventional in the art, and is generally an aluminum foil.

[0033] In the present application, the positive electrode or the negative electrode can further comprise a binder and a conductive agent.

[0034] The binder can be one or more of polyurethane, epoxy resin, polyvinylidene fluoride, carboxymethyl cellulose, styrene butadiene rubber, and polyacrylic acid.

[0035] The conductive agent can be conventional in the art, such as Super P.

[0036] In the present application, the electrolyte can be conventional in the art, such as a diethylene glycol dimethyl ether solution containing 1.0 M NaPF6.

[0037] In the present application, an insulating film with high ion permeability and mechanical strength is used as a separator film. The separator film can be made of, for example, an olefin-based polymer such as polypropylene having chemical resistance and hydrophobicity; a sheet or non-woven fabric made of glass fiber, polyethylene, or the like.

[0038] In the present application, the sodium-ion battery further comprises a housing for loading the positive electrode, the negative electrode, and the electrolyte.

[0039] On the basis of common general knowledge in the art, the above-mentioned preferred conditions can be combined in any manner, thereby obtaining preferred examples of the present application.

[0040] The reagents and raw materials used in the present application are commercially available.

[0041] The positive progress effect of the present application is that:

[0042] The lattice-restricted M 0.67 NS 2-x Cl x The material effectively alleviates the volume expansion of M atoms during alloying, and exhibits excellent electrochemical performance when applied in sodium-ion batteries. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 The structure of the prepared M 0.67 NS 2-x Cl x The structure of the prepared M

[0044] Figure 2 The structure of the prepared Bi 0.67SEM image of TaS2 sample;

[0045] Figure 3 Bi 0.67 XRD pattern of TaS2 sample. DETAILED DESCRIPTION

[0046] The application will be further described in the following examples without thereby limiting the application to the examples described. The experimental methods in the following examples, where no specific conditions are mentioned, are carried out according to the conventional methods and conditions, or according to the instructions of the commercial products.

[0047] The raw materials used in the following examples and comparative examples are all commercially available without further treatment before use.

[0048] Example 1

[0049] Bi, Ta and S powders were weighed according to the stoichiometric ratio (the molar ratio of Bi:Ta:S was 0.67:1:2), and were conventionally ground by a mortar. The ground powders were placed in a quartz tube, and the quartz tube was vacuumized and sealed. The sealed quartz tube was placed in a muffle furnace for calcination, the heating rate was 3°C / min, the calcination temperature was 880°C, and the calcination time was 24 hours. After natural cooling to room temperature, Bi 0.67 TaS2 sample powder.

[0050] Example 2

[0051] Sb, Ta, TaCl2 and S powders were weighed according to the stoichiometric ratio (the molar ratio of Sb:Ta:TaCl2:S was 0.67:0.85:0.15:1.7), and were conventionally ground by a mortar. The ground powders were placed in a quartz tube, and the quartz tube was vacuumized and sealed. The sealed quartz tube was placed in a muffle furnace for calcination, the heating rate was 3°C / min, the calcination temperature was 880°C, and the calcination time was 24 hours. After natural cooling to room temperature, Bi 0.67 TaS 1.7 Cl 0.3 Sample powder.

[0052] Example 3

[0053] BiS2, Ta, TaCl2 and S powders were weighed according to the stoichiometric ratio (the molar ratio of BiS2:Ta:TaCl2:S was 0.67:0.95:0.05:0.56), and were conventionally ground by a mortar. The ground powders were placed in a quartz tube, and the quartz tube was vacuumized and sealed. The sealed quartz tube was placed in a muffle furnace for calcination, the heating rate was 3°C / min, the calcination temperature was 880°C, and the calcination time was 24 hours. After natural cooling to room temperature, Bi 0.67 TaS 1.9 Cl 0.1 Sample powder.

[0054] Comparative Example 1

[0055] Ta powder and S powder with a molar ratio of 1:2 were ground and placed in a quartz tube. The quartz tube was evacuated and sealed, and then placed in a muffle furnace for calcination at a heating rate of 3°C / min, a calcination temperature of 900°C, and a calcination time of 24 hours. After naturally cooling to room temperature, TaS2 sample powder was obtained.

[0056] Effect embodiment

[0057] (1) TEM and HRTEM testing

[0058] according to Figure 1 As can be seen from the structural diagram of the prepared Bi 0.67 In TaS2, Ta atoms combine with six S atoms to form a side-shared TaS6 prism, while Bi atoms combine with two S atoms to form a linear geometry.

[0059] according to Figure 2 It can be seen that the prepared Bi 0.67 The TaS2 sample is micron-sized and presents a hexagonal flake morphology. In addition, according to the HRTEM test results, Bi 0.67 The interlayer spacing corresponding to the (1-20) crystal plane and (2-10) crystal plane of the TaS2 sample is 0.288nm.

[0060] (2) XRD and BET tests

[0061] The samples were subjected to XRD, Raman and specific surface area tests using conventional test methods in the field. XRD characterization was performed on a Bruker D8 Advance diffractometer using Cu Kα radiation. The BET test was carried out at liquid nitrogen temperature using ASAP 2020M for nitrogen adsorption and desorption testing.

[0062] Figure 3 The XRD spectrum of Bi 0.67 The crystal structure of TaS2 sample, Bi 0.67 TaS2 belongs to the hexagonal crystal system with space group P63 / mcm. The characteristic diffraction peaks are located at 10.14°, 17.96°, 20.36°, 31.36°, 33.04°, 41.40°, 44.49°, 55.82° and 60.05°, corresponding to the (002), (100), (004), (2-10), (2-12), (008), (2-16), (300) and (304) crystal planes, respectively.

[0063] The crystals prepared in Examples 1-3 are isomorphs, having the same crystal system and space group.

[0064] According to the BET test results, Bi 0.67 TaS2has a specific surface area of 0.5560m 2 / g.

[0065] (3) Conductivity test

[0066] The resistivity test as a function of temperature was performed using a physical property measurement system (PPMS, Quantum Design). In the conductivity test, the sample powder was pressed into a square disc, and silver paste was used as the contact electrode.

[0067] According to the test results, Bi 0.67 TaS2has a positive correlation with temperature, confirming the metallic property inherited from metallic TaS2. At room temperature (298 K), the conductivity of Bi 0.67 TaS2is 75 times that of TaS2.

[0068] (4) Electrochemical performance test

[0069] 1. The sodium storage performance of the prepared Bi 0.67 TaS2material was evaluated by assembling CR2032 button cells. The active material prepared in Examples 1-3 and Comparative Example 1, conductive carbon black (Super P), and polyvinylidene fluoride (PVDF) binder were mixed in a mass ratio of 8:1:1, and anhydrous ethanol was added as a solvent and stirred until uniform. A slurry was then prepared. The slurry was then uniformly coated on a copper foil and dried at 100°C under vacuum for 12 hours. The average mass of active material on each wafer was 1.0-1.2 mg cm -2 . Half-cells were assembled with a sodium wafer (Canrd, 99.7%, 15.6*0.45 mm) as the counter electrode and glass fiber (GF / D, Whatman) as the separator in an argon-filled glove box (MBRAUN-LABstar, H2O and O2 content less than 0.5 ppm). The electrolyte was a solution of 1.0 M NaPF6 in diethylene glycol dimethyl ether (DEGDME). The specific capacity of the half-cell was calculated based on the total mass of the anode. Before measurement, the battery was allowed to stand for 8 hours to ensure that the electrolyte and active material were in good contact. Static charge-discharge measurements were performed on a battery test system (LAND-CT2001A) with a voltage range of 0.01-3 V.

[0070] The sodium storage performance of the prepared material was studied by assembling a CR2032 button cell with sodium metal as the counter electrode. The cycling stability was evaluated by electrostatic charge-discharge (GCD) curves in the voltage window of 0.01-3.0 V. -1 ) conditions, the Bi prepared in Example 1 0.67 The GCD curve of the TaS2 electrode shows that the discharge / charge capacity of the first cycle is 431 / 271 mAh g -1 , see Table 1. 0.67 The average charging voltage of TaS2 is close to 0.8V, and the initial coulombic efficiency (ICE) is 62.9%. The charging current density is 1C, 5C, 10C, 25C, 50C, 75C, 100C, 125C and 150C (1C = 200mAg -1 ), Bi 0.67 The charge capacities of TaS2 anodes are 257, 262, 258, 246, 239, 227, 216, 200, and 188 mAh g -1 At 30A g -1 At high current density, Bi 0.67 The capacity retention rate of TaS2 is 72.8%, which is comparable to that of TaS2 (26.2 mAh g -1 , 20.5%) and Bi (76.6 mAh g -1 , 19.7%) anode compared to Bi 0.67 TaS2 has higher capacity and better rate capability. Bi was further tested at current densities of 25C, 50C and 150C. 0.67 Long-term cycling performance of TaS2 anode. Cycling 2000 times (5Ag -1 ), Bi 0.67 The TaS2 anode can deliver 218.5 mAh g -1 The high reversible capacity of the Bi anode decreased significantly, only 141.8 mAh g -1 Although the TaS2 anode can maintain nearly 100% capacity retention after 2000 cycles, its capacity is only 95.8 mAh g -1 . As the current density increases further, Bi 0.67 TaS2 anode at 50C (10Ag -1 ) after 2000 cycles showed 191.4 mAh g -1 The reversible capacity of Bi and TaS2 anodes is only 114.9 mAh g -1 and 80.1mAhg -1Even at ultra-high current densities up to 150C (30Ag-1), Bi 0.67 The TaS2 anode can still deliver 160.8 mAh g after 20,000 cycles. -1 At the same current density, the Bi anode will be overcharged after 200 cycles due to structural deformation, while the capacity of the TaS2 anode will only drop to 30 mAh g after several cycles. -1 , much lower than Bi 0.67 Capacity of TaS2 anode.

[0071] Table 1 Examples 1-3 at 0.2C (1C = 200mA g -1 ) and the first cycle charge and discharge capacity at 50C (10Ag -1 ) Reversible capacity after 2000 cycles

[0072]

[0073] 2. Preparation of Bi 0.67 TaS2||Na3V2(PO4)3(NVP) full battery, NVP cathode was purchased from Shenzhen Kejing Star Technology Co., Ltd. Using N-methyl-2-pyrrolidone (NMP) as solvent, NVP, SuperP and PVDF were mixed in a mass ratio of 8:1:1 to prepare cathode slurry, and then the slurry was evenly coated on aluminum foil and dried under vacuum conditions at 100°C for 12 hours. The mass ratio of cathode and anode active materials is 2:1. The electrolyte used is diethylene glycol dimethyl ether (DEGDME) solution containing 1.0M NaPF6, and glass fiber (GF / D, Whatman) is used as the separator. The specific capacity of the full battery is calculated based on the total mass of the cathode and anode. Full battery (1C=100mAg -1 ) were performed in the voltage range of 1.0-3.5V.

[0074] Full battery at 0.2C (1C = 100mA g -1 ) conditions, the initial charge and discharge capacity is 117.8 / 105.5mAh g -1 , the initial Coulombic efficiency is 89.6%. NVP||Bi 0.67 The capacity-voltage curve of the TaS2 full cell shows its reversible discharge / charge capability in a wide range from 0.2C to 10C. The full cell has excellent rate capability, with discharge capacities of 107.8, 105.9, 103.7, 100.5, 89.6, and 74.3 mAh g at 0.2C, 0.5C, 1C, 2C, 5C, and 10C, respectively. -1 According to the discharge time and median voltage, the power density is 34.3Wkg -1The energy density of the full cell is 173.9 Wh kg -1 Even under the high power condition of 1396.3 W kg -1 , the full cell can still maintain an energy density of 97.9 Wh kg -1 . The NVP||Bi 0.67 TaS2full cell also exhibits excellent cycle stability, with a capacity of 77.7 mAh g -1 after 100 cycles at 1C.

[0075] Although the specific embodiments of the present application are described above, those skilled in the art should understand that this is only an example, and the protection scope of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present application, and such changes and modifications fall within the protection scope of the present application.

Claims

1. A lattice-limited M 0.67 NS 2-x Cl x Material, characterized in that It belongs to the hexagonal crystal system with space group P63 / mcm; M is Sb and / or Bi, N is Ta, 0≤x<0.5; By multiple NS 6-y Cl y The single layer stacked, the NS 6-y Cl y The monolayer consists of N atoms combined with S atoms and Cl atoms to form side-shared NS 6-y Cl y Prism layer, the sum of the number of the S atoms and the Cl atoms bonded to the N atoms is 6, and the M atoms are intercalated into the adjacent NS 6-y Cl y In the interlayer of the prism layer, each M atom is bonded to two adjacent NS 6-y Cl y One S atom or Cl atom in each of the prism layers combines to form a linear geometric structure, 0≤y<0.

5.

2. The lattice-limited M according to claim 1 0.67 NS 2-x Cl x Material, characterized in that The lattice-limited M 0.67 NS 2-x Cl x In the material, 0<x<0.5; and / or, the lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 TaS2、Bi 0.67 TaS 1.7 Cl 0.3 Or Bi 0.67 TaS 1.9 Cl 0.1 ; and / or, the lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 In the case of TaS2, using Cu Kα radiation, its X-ray powder diffraction shows characteristic diffraction peaks at diffraction angles 2θ of 10.14°, 17.96°, 20.36°, 31.36°, 33.04°, 41.40°, 44.49°, 55.82° and 60.05°.

3. The lattice-limited M according to claim 2 0.67 NS 2-x Cl x Material, characterized in that The lattice-limited M 0.67 NS 2-x Cl x In the material, x is 0.1, 0.2 or 0.

3.

4. The lattice-limited M according to claim 2 0.67 NS 2-x Cl x Material, characterized in that The lattice-limited M 0.67 NS 2-x Cl x In the material, 0.15<x<0.

4.

5. A lattice-limited M according to any one of claims 1 to 4. 0.67 NS 2-x Cl x The method for preparing the material is characterized in that: The method comprises the following steps: subjecting the raw materials of "S source and / or Cl source", M source and N source to a high temperature solid phase reaction in a vacuum environment to obtain the lattice-restricted M 0.67 NS 2-x Cl x Material; The temperature of the high-temperature solid-phase reaction is 800-1200° C., and the time of the high-temperature solid-phase reaction is 20-48 hours.

6. The lattice-limited M according to claim 5 0.67 NS 2-x Cl x The method for preparing the material is characterized in that: The N source is elemental N, N-containing sulfide or N-containing chloride; And / or, the M source is M element, M-containing sulfide or M-containing chloride; And / or, the S source is a single substance of S or a compound containing S; And / or, the Cl source is a chloride containing N or a chloride containing M; And / or, in the raw material, the molar ratio of M atoms, N atoms, S atoms and Cl atoms is 0.67:1:2-x:x.

7. The lattice-limited M according to claim 6 0.67 NS 2-x Cl x The method for preparing the material is characterized in that: The N source is Ta, TaS2, or TaCl2; And / or, the M source is Bi, Sb, BiS2 or SbCl3; And / or, the S source is S, TaS2 or BiS2; And / or, the Cl source is TaCl2.

8. The lattice-limited M according to claim 5 0.67 NS 2-x Cl x The method for preparing the material is characterized in that: The lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 TaS2, the M source is Bi powder, the N source is Ta powder, the S source is S powder, and the molar ratio of the Bi powder, the Ta powder, and the S powder is 0.67:1:2; Or, the lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 TaS 1.7 Cl 0.3 , the M source is Sb powder, the N source and the Cl source are Ta powder and TaCl2, the S source is S powder, and the molar ratio of the Sb powder, the Ta powder, the TaCl2 and the S powder is 0.67:0.85:0.15:1.7; Or, the lattice-limited M 0.67 NS 2-x Cl x The material is Bi 0.67 TaS 1.9 Cl 0.1 The M source is BiS2, the N source and the Cl source are TaCl2 and Ta powder, the sulfur source is S powder, and the molar ratio of the BiS2, the Ta powder, the TaCl2 and the S powder is 0.67:0.95:0.05:0.

56.

9. The lattice-limited M according to claim 5 0.67 NS 2-x Cl x The method for preparing the material is characterized in that: The temperature of the high-temperature solid-phase reaction is 800-1000°C.

10. The lattice-limited M according to claim 5 0.67 NS 2-x Cl x The method for preparing the material is characterized in that: The high temperature solid phase reaction time is 20-30h.

11. The lattice-limited M according to claim 5 0.67 NS 2-x Cl x The method for preparing the material is characterized in that: The lattice-limited M 0.67 NS 2-x Cl x The preparation method of the material comprises the following steps: grinding and mixing "S source and / or Cl source", M source and N source to obtain raw material powder; placing the raw material powder in a reaction tube, evacuating and sealing the reaction tube, and then performing a high-temperature solid-phase reaction to obtain the lattice-restricted M 0.67 NS 2-x Cl x Material.

12. A lattice-limited M according to any one of claims 1 to 4. 0.67 NS 2-x Cl x Application of materials in sodium-ion batteries.

13. A sodium ion battery, characterized in that: The electrolyte comprises a positive electrode, a negative electrode, an electrolyte and a separator, wherein the negative electrode comprises a lattice-restricted M as claimed in any one of claims 1 to 4. 0.67 NS 2-x Cl x Material.

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