A SnS / WS2@C composite electrode material, its preparation method and its application
By preparing SnS/WS2@C composite electrode materials, the problems of poor conductivity and low capacity of tungsten disulfide in potassium-ion batteries were solved, achieving high-efficiency potassium-ion storage performance and improving the electrochemical performance and stability of potassium-ion batteries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHAANXI UNIV OF SCI & TECH
- Filing Date
- 2023-11-28
- Publication Date
- 2026-06-02
AI Technical Summary
Tungsten disulfide, as a negative electrode material for potassium-ion batteries, suffers from poor conductivity and low theoretical capacity, resulting in poor performance in potassium-ion batteries.
By preparing SnS/WS2@C composite electrode materials, a multi-step solvothermal method was used to combine SnS and WS2 with carbon. The content of each precursor, reaction temperature and time were controlled to ensure that WS2 grows on the SnS surface, forming a stable structure, providing ion transport channels and avoiding damage to the electrode structure.
The electrochemical performance of the potassium-ion battery was improved, with an initial capacity of 650 mAh/g and a cycle performance of over 400 within 100 cycles, demonstrating good stability and rapid potassium-ion storage capacity.
Smart Images
Figure CN117645319B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of tungsten disulfide nanomaterials technology, and relates to a SnS / WS2@C composite electrode material, its preparation method and its application. Background Technology
[0002] The widespread use of fossil fuels has greatly promoted the development of modern industry. While the large-scale development and utilization of coal, oil, and natural gas have provided benefits to life, they have also caused energy crises and environmental pollution. Therefore, finding clean energy sources to replace traditional fossil fuels has become a major trend in development. Lithium-ion batteries (LIBs), as an emerging clean energy source, are widely used in mobile devices, electric vehicles, and other fields due to their advantages such as high energy density, long lifespan, and wide operating temperature range. However, with the rapid growth in human demand for lithium-ion batteries, limited lithium resources have become an increasingly prominent problem, making the development of alternative energy storage methods beyond lithium-ion batteries imperative.
[0003] Potassium-ion batteries (PIBs) are attracting increasing attention from researchers due to their low cost and abundant reserves. Furthermore, PIBs offer a wider electrochemical window and higher energy density. Potassium ions have a smaller solvation ionic radius and lower Lewis acidity, resulting in stronger ion transport capabilities. Meanwhile, potassium... + The large radius of the anode material can easily cause crushing and damage, resulting in unsatisfactory cycle performance. Tungsten disulfide (WS2) belongs to the transition metal chalcogenide family and is a typical graphene-like layered sulfide (TMDs). The interlayer spacing is about 0.62 nm. The large interlayer spacing can provide more active sites for potassium ion insertion and extraction, making it an ideal anode material for potassium-ion batteries.
[0004] However, research has revealed that while tungsten disulfide possesses many advantages, it also has drawbacks in application. Firstly, as an intrinsic semiconductor, tungsten disulfide exhibits poor conductivity, resulting in poor rate performance when used in potassium-ion batteries. Secondly, the theoretical capacity of tungsten disulfide is only 433 mAh g⁻¹. -1 Further improvements are needed. If tungsten disulfide could be molded into a bridge connecting potassium ions and high-capacity materials, it could significantly improve the performance of potassium-ion batteries. Summary of the Invention
[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a SnS / WS2@C composite electrode material, a preparation method and its application, to solve the problem of low performance of existing potassium-ion batteries.
[0006] To achieve the above objectives, the present invention employs the following technical solution:
[0007] The first aspect of this invention discloses a method for preparing a SnS / WS2@C composite electrode material, comprising the following steps:
[0008] 1) SnCl2·2H2O and CH3CSNH2 were uniformly dispersed in anhydrous ethanol to obtain precursor solution A;
[0009] 2) After the precursor liquid A obtained in step 1) undergoes a solvothermal reaction, it is cooled, centrifuged, washed, and freeze-dried to obtain powder B;
[0010] 3) Disperse the powder B, WCl6 and CH3CSNH2 obtained in step 2) uniformly in anhydrous ethanol to obtain solution C;
[0011] 4) After the solution C obtained in step 3) undergoes a solvothermal reaction, it is cooled, centrifuged, washed, and freeze-dried to obtain powder D;
[0012] 5) Disperse the powder D obtained in step 4) with glucose in deionized water and mix well to obtain precursor solution E;
[0013] 6) After the precursor liquid E obtained in step 5) undergoes a solvothermal reaction, it is cooled, centrifuged, washed, and freeze-dried to obtain powder F. Powder F is then calcined at 500-800℃ to obtain SnS / WS2@C composite electrode material.
[0014] Preferably, in step 1), the mass ratio of SnCl2·2H2O to CH3CSNH2 is 3:1.
[0015] Preferably, in step 3), the mass ratio of powder B, WCl6, and CH3CSNH2 is 10:(3-17):(10-33).
[0016] Preferably, in step 5), the mass ratio of powder D to glucose is 1:(1-5).
[0017] Preferably, the mixing method in steps 1), 3), and 5) is to stir for 30 to 90 minutes at a speed of 300 to 600 r / min.
[0018] Preferably, in steps 2), 4), and 6), during the solvothermal reaction, the volume filling ratio of the reactants in the reactor is 20% to 80%.
[0019] Preferably, in step 2), the temperature of the solvothermal reaction is 80–200°C and the holding time is 1–6 h; in step 4), the temperature of the solvothermal reaction is 160–240°C and the holding time is 1–24 h; in step 6), the temperature of the solvothermal reaction is 100–200°C and the holding time is 1–12 h.
[0020] Preferably, in steps 2), 4), and 6), the centrifugation, washing, and freeze-drying steps are as follows: centrifuge and wash 3 to 6 times with anhydrous ethanol and deionized water, and freeze-dry for 6 to 24 hours at -70 to -40°C and a vacuum of 10 to 40 Pa.
[0021] In a second aspect, the present invention provides a SnS / WS2@C composite electrode material prepared by the above-described preparation method.
[0022] A third aspect of the present invention provides the application of the above-mentioned SnS / WS2@C composite electrode material in the preparation of potassium-ion batteries.
[0023] Compared with the prior art, the present invention has the following beneficial effects:
[0024] This invention provides a method for preparing a SnS / WS2@C composite electrode material. First, SnS is prepared using SnCl2·2H2O as a tin source and CH3CSNH2 as a sulfur source; WS2 is prepared using WCl6 as a tungsten source and CH3CSNH2 as a sulfur source; and glucose is used as a carbon source. The SnS, WS2, and C are then combined to prepare the electrode. In the resulting composite electrode material, SnS possesses a high theoretical capacity, WS2 stabilizes the structure and provides ion transport channels, and the C coating on the outermost layer prevents severe side reactions during charge and discharge. This allows the composite electrode material to fully utilize the capacity advantage of SnS and achieve stable and rapid potassium ion storage. Second, the stepwise solvothermal reaction ensures that SnS and WS2 are not generated simultaneously, but rather that WS2 grows on the surface of SnS. The WS2 growing on the SnS surface ensures the stability of the electrode material during charge and discharge, effectively maintaining the electrode structure and reducing structural damage caused by volume expansion. Thirdly, anhydrous ethanol is used as the reaction solvent. Anhydrous ethanol contains a very small amount of water, which promotes the formation of SnS without causing hydrolysis to form Sn hydroxide. This method allows for precise control of the morphology, size, and carbon coating thickness of the SnS / WS2@C composite electrode material by adjusting parameters such as the content of precursors, reaction temperature, and reaction time. The SnS / WS2@C composite electrode material is synthesized stepwise via a multi-step solvothermal method, with controllable and easily adjustable process parameters. Performance testing of the prepared SnS / WS2@C composite electrode material revealed an initial capacity of 650 mAh / g, which remained above 400 mAh / g over 100 cycles, demonstrating good electrochemical performance as a potassium-ion battery anode. Attached Figure Description
[0025] Figure 1 The XRD pattern of the SnS / WS2@C prepared according to the present invention;
[0026] Figure 2This is a low-magnification SEM image of SnS / WS2@C prepared according to the present invention;
[0027] Figure 3 This is a high-magnification SEM image of SnS / WS2@C prepared according to the present invention;
[0028] Figure 4 The elemental distribution diagram of SnS / WS2@C prepared in this invention;
[0029] Figure 5 The diagram shows the cycling performance of SnS / WS2@C prepared according to this invention. Detailed Implementation
[0030] To enable those skilled in the art to understand the features and effects of the present invention, the following descriptions and definitions are only general descriptions of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in the event of any conflict, the definitions in this specification shall prevail.
[0031] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.
[0032] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values (including integers and fractions) within those ranges.
[0033] In this article, unless otherwise specified, “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of,” for example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a.”
[0034] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.
[0035] This invention provides a method for preparing SnS / WS2@C composite electrode material, the specific steps of which are as follows:
[0036] ① Weigh out stannous chloride dihydrate (SnCl2·2H2O) and thioacetamide (CH3CSNH2) in a mass ratio of 3:1 and disperse them in sufficient anhydrous ethanol. Stir at 300-600 r / min for 30-90 min to obtain precursor solution A.
[0037] ② Transfer the precursor solution A obtained in step ① to a polytetrafluoroethylene-lined high-pressure reactor, maintaining the volumetric filling ratio of precursor solution A in the reactor between 20% and 80%. Place the sealed reactor into a homogeneous reactor, set the temperature parameters to 80℃ to 200℃, and the holding time to 1 to 6 hours.
[0038] ③ After the solvothermal reaction, the product system was cooled to room temperature to obtain the product system. The product system was centrifuged and washed 3 to 6 times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum degree of 10 to 40 Pa for 6 to 24 hours to obtain powder B.
[0039] ④ Weigh out powder B, tungsten hexachloride (WCl6) and CH3CSNH2 in a mass ratio of 10:(3~17):(10~33) and disperse them in sufficient anhydrous ethanol. Stir at 300~600r / min for 30~90min to obtain solution C.
[0040] ⑤ Transfer the precursor solution C to a polytetrafluoroethylene-lined high-pressure reactor, maintaining the volumetric filling ratio of the precursor solution C in the reactor between 20% and 80%. Place the sealed reactor into a homogeneous reactor, set the temperature parameters to 160℃ to 240℃, and maintain the temperature for 1 to 24 hours.
[0041] ⑥ After the solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed 3–6 times with anhydrous ethanol and deionized water, respectively. The washed product was then placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10–40 Pa for 6–24 hours to obtain powder D.
[0042] ⑦ Mix powder D with glucose (C6H) 12 O6) was dispersed in 20-80 mL of deionized water at a mass ratio of 1:(1-5), and stirred at 300-600 r / min for 30-90 min to obtain precursor solution E.
[0043] ⑧ Transfer the precursor solution E to a polytetrafluoroethylene-lined high-pressure reactor, maintaining the volumetric filling ratio of the precursor solution E in the reactor between 20% and 80%. Place the sealed reactor into a homogeneous reactor, set the temperature parameters to 100℃ to 200℃, and maintain the temperature for 1 to 12 hours.
[0044] ⑨ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed 3–6 times with anhydrous ethanol and deionized water, respectively. The washed product was then placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10–40 Pa for 6–24 hours to obtain powder F.
[0045] ⑩ Grind powder F in an agate mortar and transfer it to a porcelain boat. Place the porcelain boat in a tube furnace, set the calcination temperature to 500-800℃, the heating rate to 2-10 min, and hold for 1-6 h to obtain the SnS / WS2@C composite electrode material.
[0046] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.
[0047] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.
[0048] Example 1
[0049] ① Weigh 0.563 g of stannous chloride dihydrate (SnCl2·2H2O) and 0.188 g of thioacetamide (CH3CSNH2), disperse them in 40 mL of anhydrous ethanol, and stir magnetically until homogeneous to obtain precursor solution A. The stirring rate was 400 r / min, and the stirring time was 30 min.
[0050] ② Transfer precursor solution A to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 40%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 80℃, and maintain the temperature for 1 hour.
[0051] ③ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa for 6 hours to obtain powder B.
[0052] ④ Weigh 0.35g of powder B, 0.59g of tungsten hexachloride (WCl6) and 1.125g of CH3CSNH2 and disperse them in 30mL of anhydrous ethanol. Stir magnetically until homogeneous to obtain solution C. The stirring speed is 400r / min and the stirring time is 30min.
[0053] ⑤ Transfer the precursor solution C to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 30%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 160℃, and the holding time to 6h.
[0054] ⑥ After a solvothermal reaction, the mixture was cooled to room temperature to obtain the product system. The product system was centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 6 hours to obtain powder D.
[0055] ⑦ Mix powder D with glucose (C6H) 12 O6) was dispersed in 80 mL of deionized water at a mass ratio of 1:1 and stirred magnetically until homogeneous to obtain precursor solution E. The stirring speed was 400 r / min and the stirring time was 30 min.
[0056] ⑧ Transfer the precursor solution E to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volumetric filling ratio of around 50%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 140℃, and maintain the temperature for 12 hours.
[0057] ⑨ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa for 6 hours to obtain powder F.
[0058] ⑩ Grind powder F in an agate mortar and transfer it to a porcelain boat. Place the porcelain boat in a tube furnace, set the calcination temperature to 500℃, the heating rate to 5 min, and hold for 2 h to obtain the SnS / WS2@C composite electrode material.
[0059] Example 2
[0060] ① Weigh 1.13g of stannous chloride dihydrate (SnCl2·2H2O) and 0.376g of thioacetamide (CH3CSNH2) and disperse them in 60mL of anhydrous ethanol. Stir the mixture magnetically until homogeneous to obtain precursor solution A. The stirring rate is 500r / min and the stirring time is 30min.
[0061] ② Transfer precursor solution A to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 60%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 200℃, and maintain the temperature for 1 hour.
[0062] ③ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed six times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder B.
[0063] ④ Weigh 0.75g of powder B, 1.19g of tungsten hexachloride (WCl6) and 2.25g of CH3CSNH2 and disperse them in 60mL of anhydrous ethanol. Stir magnetically until homogeneous to obtain solution C. The stirring speed is 500r / min and the stirring time is 60min.
[0064] ⑤ Transfer the precursor solution C to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 60%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 200℃, and maintain the temperature for 1 hour.
[0065] ⑥ After a solvothermal reaction, the mixture was cooled to room temperature to obtain the product system. The product system was centrifuged and washed 6 times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder D.
[0066] ⑦ Mix powder D with glucose (C6H) 12 O6) was dispersed in 60 mL of deionized water at a mass ratio of 1:2 and magnetically stirred until homogeneous to obtain precursor solution E. The stirring speed was 500 r / min and the stirring time was 30 min.
[0067] ⑧ Transfer the precursor solution E to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volumetric filling ratio of around 60%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 180℃, and hold for 3 hours.
[0068] ⑨ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed six times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder F.
[0069] ⑩ Grind powder F in an agate mortar and transfer it to a porcelain boat. Place the porcelain boat in a tube furnace, set the calcination temperature to 500℃, the heating rate to 10 min, and hold for 2 h to obtain the SnS / WS2@C composite electrode material.
[0070] The performance of the prepared SnS / WS2@C composite electrode material was tested, and the XRD pattern is shown in the figure. Figure 1As can be seen, the XRD patterns of the prepared SnS / WS2@C correspond well with the standard SnS and WS2 cards. See SEM images below. Figure 2 and Figure 3 As can be seen, the prepared material exhibits a flower-like structure with a distinct coating layer on the surface, indicating that C effectively coats SnS / WS2. See the elemental distribution image below. Figure 4 As can be seen, the various elements are uniformly distributed in the material, without any separate growth, indicating that SnS and WS2 are well composited. See the cycle performance results below. Figure 5 The SnS / WS2@C composite electrode material obtained had a cycle performance of 650 mAh / g in the first cycle and could maintain above 400 mAh / g within 100 cycles, indicating that the electrode material has excellent stability and high reversible capacity.
[0071] Example 3
[0072] ① Weigh 5.63g of stannous chloride dihydrate (SnCl2·2H2O) and 1.88g of thioacetamide (CH3CSNH2) and disperse them in 60mL of anhydrous ethanol. Stir the mixture magnetically until homogeneous to obtain precursor solution A. The stirring rate is 600r / min and the stirring time is 90min.
[0073] ② Transfer precursor solution A to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 60%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 160℃, and maintain the temperature for 3 hours.
[0074] ③ After the solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa for 24 hours to obtain powder B.
[0075] ④ Weigh 3.5g of powder B, 5.9g of tungsten hexachloride (WCl6) and 11.25g of CH3CSNH2 and disperse them in 80mL of anhydrous ethanol. Stir magnetically until homogeneous to obtain solution C. The stirring speed is 600r / min and the stirring time is 90min.
[0076] ⑤ Transfer the precursor solution C to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 40%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 160℃, and maintain the temperature for 24 hours.
[0077] ⑥ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa for 24 hours to obtain powder D.
[0078] ⑦ Mix powder D with glucose (C6H) 12 O6) was dispersed in 50 mL of deionized water at a mass ratio of 1:5 and stirred magnetically to obtain precursor solution E. The stirring speed was 600 r / min and the stirring time was 90 min.
[0079] ⑧ Transfer the precursor solution E to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 50%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 200℃, and maintain the temperature for 12 hours.
[0080] ⑨ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa for 24 hours to obtain powder F.
[0081] ⑩ Grind powder F in an agate mortar and transfer it to a porcelain boat. Place the porcelain boat in a tube furnace, set the calcination temperature to 800℃, the heating rate to 10 min, and hold for 4 h to obtain the SnS / WS2@C composite electrode material.
[0082] Example 4
[0083] ① Weigh 3.38g of stannous chloride dihydrate (SnCl2·2H2O) and 1.13g of thioacetamide (CH3CSNH2) and disperse them in 40mL of anhydrous ethanol. Stir the mixture magnetically until homogeneous to obtain precursor solution A. The stirring rate is 450r / min and the stirring time is 60min.
[0084] ② Transfer precursor solution A to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 40%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 120℃, and maintain the temperature for 4 hours.
[0085] ③ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder B.
[0086] ④ Weigh 2.25g of powder B, 0.83g of tungsten hexachloride (WCl6) and 2.25g of CH3CSNH2 and disperse them in 50mL of anhydrous ethanol. Stir magnetically until homogeneous to obtain solution C. The stirring speed is 450r / min and the stirring time is 90min.
[0087] ⑤ Transfer the precursor solution C to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 50%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 240℃, and maintain the temperature for 4 hours.
[0088] ⑥ After the solvothermal reaction, the product system was cooled to room temperature. The product system was centrifuged and washed five times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder D.
[0089] ⑦ Mix powder D with glucose (C6H) 12 O6) was dispersed in 50 mL of deionized water at a mass ratio of 1:3 and magnetically stirred until homogeneous to obtain precursor solution E. The stirring speed was 450 r / min and the stirring time was 60 min.
[0090] ⑧ Transfer the precursor solution E to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 50%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 160℃, and maintain the temperature for 6 hours.
[0091] ⑨ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder F.
[0092] ⑩ Grind powder F in an agate mortar and transfer it to a porcelain boat. Place the porcelain boat in a tube furnace, set the calcination temperature to 600℃, the heating rate to 5 min, and hold for 2 h to obtain the SnS / WS2@C composite electrode material.
[0093] Example 5
[0094] ① Weigh 1.13g of stannous chloride dihydrate (SnCl2·2H2O) and 0.377g of thioacetamide (CH3CSNH2) and disperse them in 20mL of anhydrous ethanol. Stir the mixture magnetically until homogeneous to obtain precursor solution A. The stirring rate is 300r / min and the stirring time is 50min.
[0095] ② Transfer precursor solution A to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 80%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 120℃, and maintain the temperature for 6 hours.
[0096] ③ After a solvothermal reaction, the mixture was cooled to room temperature to obtain the product system. The product system was centrifuged and washed four times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 24 hours to obtain powder B.
[0097] ④ Weigh 0.75g of powder B, 0.225g of tungsten hexachloride (WCl6) and 0.75g of CH3CSNH2 and disperse them in 20mL of anhydrous ethanol. Stir magnetically until homogeneous to obtain solution C. Stir at a rate of 300r / min for 90min.
[0098] ⑤ Transfer the precursor solution C to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 80%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 240℃, and maintain the temperature for 4 hours.
[0099] ⑥ After a solvothermal reaction, the mixture was cooled to room temperature to obtain the product system. The product system was centrifuged and washed four times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder D.
[0100] ⑦ Mix powder D with glucose (C6H) 12 O6) was dispersed in 20 mL of deionized water at a mass ratio of 1:4 and magnetically stirred until homogeneous to obtain precursor solution E. The stirring speed was 300 r / min and the stirring time was 60 min.
[0101] ⑧ Transfer the precursor solution E to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 80%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 100℃, and maintain the temperature for 1 hour.
[0102] ⑨ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed four times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 12 hours to obtain powder F.
[0103] ⑩ Take powder F and grind it in an agate mortar, then transfer it to a porcelain boat. Place the porcelain boat in a tube furnace, set the calcination temperature to 500℃, the heating rate to 2 min, and hold for 6 h to obtain the SnS / WS2@C composite electrode material.
[0104] Example 6
[0105] ① Weigh 1.13g of stannous chloride dihydrate (SnCl2·2H2O) and 0.377g of thioacetamide (CH3CSNH2) and disperse them in 80mL of anhydrous ethanol. Stir the mixture magnetically until homogeneous to obtain precursor solution A. The stirring speed is 300r / min and the stirring time is 50min.
[0106] ② Transfer precursor solution A to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 20%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 120℃, and maintain the temperature for 6 hours.
[0107] ③ After the solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa for 24 hours to obtain powder B.
[0108] ④ Weigh 0.75g of powder B, 1.275g of tungsten hexachloride (WCl6) and 2.475g of CH3CSNH2 and disperse them in 20mL of anhydrous ethanol. Stir magnetically until homogeneous to obtain solution C. The stirring speed is 300r / min and the stirring time is 90min.
[0109] ⑤ Transfer the precursor solution C to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 20%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 240℃, and maintain the temperature for 4 hours.
[0110] ⑥ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa and freeze-dried for 20 hours to obtain powder D.
[0111] ⑦ Mix powder D with glucose (C6H) 12 O6) was dispersed in 20 mL of deionized water at a mass ratio of 1:4 and magnetically stirred until homogeneous to obtain precursor solution E. The stirring speed was 300 r / min and the stirring time was 60 min.
[0112] ⑧ Transfer the precursor solution E to a polytetrafluoroethylene-lined high-pressure reactor, maintaining a volume filling ratio of 20%. Place the sealed reactor into a homogeneous reactor, set the temperature parameter to 100℃, and maintain the temperature for 1 hour.
[0113] ⑨ After a solvothermal reaction, the product system was cooled to room temperature. The product system was then centrifuged and washed three times with anhydrous ethanol and deionized water, respectively. The washed product was placed in a freeze dryer at -40℃ to -70℃ and a vacuum of 10 to 40 Pa for 20 hours to obtain powder F.
[0114] ⑩ Grind powder F in an agate mortar and transfer it to a porcelain boat. Place the porcelain boat in a tube furnace, set the calcination temperature to 800℃, the heating rate to 2 min, and hold for 1 h to obtain the SnS / WS2@C composite electrode material.
[0115] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.
Claims
1. A method for preparing a SnS / WS2@C composite electrode material, characterized in that, The steps are as follows: 1) SnCl2·2H2O and CH3CSNH2 in a mass ratio of 3:1 were uniformly dispersed in anhydrous ethanol to obtain precursor solution A; 2) After the precursor liquid A obtained in step 1) undergoes a solvothermal reaction, it is cooled, centrifuged, washed, and freeze-dried to obtain powder B; 3) Disperse powder B, WCl6 and CH3CSNH2 obtained in step 2) in anhydrous ethanol in a mass ratio of 10:(3~17):(10~33) to obtain solution C; 4) After the solution C obtained in step 3) undergoes a solvothermal reaction, it is cooled, centrifuged, washed, and freeze-dried to obtain powder D; 5) Disperse the powder D obtained in step 4) with glucose in deionized water at a mass ratio of 1:(1~5) and mix well to obtain precursor solution E; 6) After the precursor liquid E obtained in step 5) undergoes a solvothermal reaction, it is cooled, centrifuged, washed, and freeze-dried to obtain powder F. Powder F is then calcined at 500~800℃ to obtain SnS / WS2@C composite electrode material.
2. The method for preparing a SnS / WS2@C composite electrode material according to claim 1, characterized in that, The mixing method in steps 1), 3), and 5) is to stir at 300-600 r / min for 30-90 min.
3. The method for preparing a SnS / WS2@C composite electrode material according to claim 1, characterized in that, In steps 2), 4), and 6), during the solvothermal reaction, the volume filling ratio of the reactants in the reactor is 20% to 80%.
4. The method for preparing a SnS / WS2@C composite electrode material according to claim 1, characterized in that, In step 2), the temperature of the solvothermal reaction is 80~200℃ and the holding time is 1~6 h; in step 4), the temperature of the solvothermal reaction is 160~240℃ and the holding time is 1~24 h; in step 6), the temperature of the solvothermal reaction is 100~200℃ and the holding time is 1~12 h.
5. The method for preparing a SnS / WS2@C composite electrode material according to claim 1, characterized in that, In steps 2), 4), and 6), the centrifugation, washing, and freeze-drying steps are as follows: centrifuge and wash 3-6 times with anhydrous ethanol and deionized water, and freeze-dry for 6-24 hours at -70 to -40°C and a vacuum of 10 to 40 Pa.
6. The SnS / WS2@C composite electrode material prepared by any one of the preparation methods described in claims 1 to 5.
7. The application of the SnS / WS2@C composite electrode material according to claim 6 in the preparation of potassium-ion batteries.