Method for preparing 1T-phase molybdenum disulfide / stannic oxide heterojunction material by one-step method, product thereof and application of 1T-phase molybdenum disulfide / stannic oxide heterojunction material in battery material

Abstract

The invention discloses a method for preparing a 1T-phase molybdenum disulfide / stannic oxide heterojunction material by a one-step method, a product thereof and application of the 1T-phase molybdenum disulfide / stannic oxide heterojunction material to a battery material. The preparation method comprises the following steps: sequentially dissolving a molybdenum source, a sulfur source and a tin source in continuously stirred deionized water to obtain a milky white mixed solution, and continuously stirring; then carrying out ultrasonic pre-reaction to obtain a uniform light grey blue precursor solution, and continuously stirring at room temperature; putting the light grey blue precursor solution into a reaction kettle, and reacting at 180-220 DEG C for a period of time; and cleaning, drying and naturally cooling the heated product to obtain the 1T-phase molybdenum disulfide / stannic oxide heterojunction material. The heterojunction plays an important role in improving the utilization rate of sulfur, relieving the volume change of a positive electrode in the charging and discharging process and inhibiting the shuttle effect of polysulfide, the heterojunction shows excellent electrochemical performance as a sodium-ion battery negative electrode material or a lithium-sulfur battery positive electrode material, and meanwhile, the method has the characteristics of low cost, simple process, mild conditions and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery electrode materials, and specifically relates to a one-step method for preparing a 1T phase molybdenum disulfide / tin dioxide heterojunction material, a product thereof, and an application thereof in battery materials. Background Art

[0002] 1T phase molybdenum disulfide (1T-MoS 2 ) is a new type of two-dimensional layered material with high conductivity and unique electrochemical activity, and has attracted much attention in the field of energy storage. Compared with the traditional 2H phase MoS2, the 1T phase has better electron conductivity and can more effectively promote charge transfer. At the same time, SnO 2 ) also shows great potential in energy storage materials due to its high theoretical specific capacity and stable nanostructure. However, due to the low electronic conductivity of tin dioxide itself, this limits its practical application. Molybdenum disulfide materials, with their excellent conductivity and layered structure, can embed and release sodium ions in sodium ion batteries, and also have high electrochemical stability.

[0003] Therefore, forming a heterojunction between molybdenum disulfide and tin dioxide can not only significantly improve the overall electronic conductivity, but also accelerate the diffusion process of electrolyte ions in the electrode. In addition, molybdenum disulfide itself can also provide additional battery capacity, thereby greatly improving the energy density and power density of sodium-ion batteries. The heterojunction structure achieves synergistic optimization of performance by combining the high specific surface area of ​​tin dioxide and the excellent conductivity of molybdenum disulfide, showing a broader application prospect.

[0004] The hydrothermal method can simultaneously generate 1T phase molybdenum disulfide and tin dioxide in a single reaction process and construct their heterojunction. This method avoids the cumbersome operation of multiple steps, effectively improves the preparation efficiency, and ensures the uniform distribution and close contact of the two materials at the nanoscale. In addition, the hydrothermal method can precisely control the phase ratio of 1T phase molybdenum disulfide and the crystal structure of tin dioxide by regulating the reaction conditions, thereby optimizing the conductivity and electrochemical properties of the heterojunction material, and further enhancing its application potential in electrode materials. In addition, the hydrothermal method has the characteristics of simple process, environmental protection, and low energy consumption, and is suitable for large-scale production and synthesis of materials with complex structures. In view of this, the present invention is specially proposed. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing 1T-phase molybdenum disulfide / tin dioxide heterojunction materials by a one-step method, as well as products thereof and applications in battery materials, which play an important role in improving the utilization rate of sulfur, alleviating the volume change of the positive electrode during charge and discharge, and inhibiting the shuttle effect of polysulfides. It exhibits excellent electrochemical performance as a negative electrode material for sodium-ion batteries or a positive electrode material for lithium-sulfur batteries. At the same time, the method has the characteristics of low cost, simple process, and mild conditions.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows: In the first aspect, the present invention provides a method for preparing 1T-phase molybdenum disulfide / tin dioxide heterojunction materials by a one-step method, including: At room temperature, a molybdenum source, a sulfur source, and a tin source are sequentially dissolved in continuously stirred deionized water to obtain a milky white mixed solution, and continuous stirring is continued; the molybdenum source contains ammonium; the tin source is at least one of tin (IV) chloride pentahydrate and tin (II) chloride. The milky white mixed solution is subjected to ultrasonic pre-reaction to make the molybdenum source and the tin source fully contact to obtain a uniform light gray-blue precursor solution, and stirring is continued at room temperature. The light gray-blue precursor solution is placed in a reaction kettle and reacted at 180 - 220 °C for a period of time. The heated product is washed, dried, and naturally cooled to obtain 1T-phase molybdenum disulfide / tin dioxide heterojunction materials.

[0007] Preferably, the molybdenum source is at least one of ammonium molybdate tetrahydrate and ammonium tetramolybdate.

[0008] Preferably, the sulfur source is at least one of thiourea, sodium thiosulfate, and sodium sulfite.

[0009] Preferably, the continuous stirring time of the milky white mixed solution is 20 min, and the continuous stirring time of the light gray-blue precursor solution is 5 - 10 min.

[0010] Preferably, the heating time of the light gray-blue precursor solution in the reaction kettle is 18 - 24 h.

[0011] Preferably, the molybdenum source is ammonium molybdate tetrahydrate with a concentration of 0.5 - 1.5 mmol / L, the sulfur source is thiourea with a concentration of 20 - 40 mmol / L, and the tin source is tin (IV) chloride pentahydrate with a concentration of 1.0 - 2.5 mmol / L.

[0012] Preferably, the ultrasonic power of the ultrasonic pre-reaction of the milky white mixed solution is 60 - 180 W, and the ultrasonic time is 30 - 60 min.

[0013] Preferably, the heating temperature of the light gray-blue precursor solution in the reactor is 200° C., and the heating time is 24 h.

[0014] In a second aspect, the present invention provides a 1T phase molybdenum disulfide / tin dioxide heterojunction material prepared by the method.

[0015] In a third aspect, the present invention provides an application of a 1T phase molybdenum disulfide / tin dioxide heterojunction material in the preparation of a battery material, wherein the battery material is a negative electrode material for a sodium ion battery or a catalyst material for a positive electrode of a lithium sulfur battery.

[0016] By adopting the above technical solution, the beneficial effects of the present invention are: On the one hand, 1T-MoS 2 / SnO 2 The heterojunction operation is simple and easy to repeat. The heterojunction interface formed can effectively promote the transmission of lithium ions. The gap between ultra-thin nanosheets can effectively alleviate the volume expansion during the reaction process. The formation of the heterojunction interface can increase the transmission rate of lithium ions. On the other hand, the highly conductive 1T-MoS 2 The electronic conductivity of the heterojunction material can be improved, and the exposed edge sites can accelerate the redox reaction kinetics of polysulfides. At the same time, this method has the characteristics of low cost, simple process, mild conditions, etc., which is suitable for large-scale preparation. The prepared composite material can be used as the positive electrode of lithium-sulfur batteries and exhibits good electrochemical performance.

[0017] At the same time, this method has the characteristics of low cost, simple process, mild conditions, etc., and is suitable for large-scale preparation. The prepared composite material can be used as the positive electrode of lithium-sulfur batteries and exhibits good electrochemical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 1T-MoS prepared in Example 1 of the present invention 2 / SnO 2 SEM and TEM images of nanosheets, where (a) is 20 µm, (b) is 400 nm, and (c) is 10 nm.

[0020] Figure 2 1T-MoS prepared in Example 1 of the present invention 2 / SnO 2 XRD patterns of nanosheets.

[0021] Figure 3 1T-MoS prepared in Example 1 of the present invention 2 / SnO 2 Long cycle performance and Coulombic efficiency of nanosheets as cathode catalyst materials for lithium-sulfur batteries at 2 C current density.

[0022] Figure 4 The MoS prepared in Comparative Example 1 of the present invention 2 / SnO 2 XRD pattern of .

[0023] Figure 5 The SnS prepared in Comparative Example 3 of the present invention 2 XRD pattern of .

[0024] Figure 6 The MoS prepared in Comparative Example 4 of the present invention 2 XRD pattern of . DETAILED DESCRIPTION

[0025] As mentioned above, in view of the shortcomings of the prior art, the inventors of this case, after long-term research and extensive practice, proposed the one-step method for preparing 1T-phase molybdenum disulfide / tin dioxide heterojunction materials and their products and applications in battery materials.

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] This embodiment provides a one-step method for preparing a 1T phase molybdenum disulfide / tin dioxide heterojunction material, comprising the following steps: Step S1, dissolving the molybdenum source, sulfur source and tin source containing ammonium radicals in deionized water with continuous stirring at room temperature in turn to obtain a milky white mixed solution, and continuing to stir at room temperature for a period of time.

[0028] In one embodiment, the molybdenum source is at least one of ammonium molybdate tetrahydrate and ammonium tetramolybdate, the sulfur source is at least one of thiourea, sodium thiosulfate, and sodium sulfite, and the tin source is at least one of tin tetrachloride pentahydrate and tin chloride.

[0029] Compared with the clear solution when there are only molybdenum source and sulfur source, the tin source is very easy to undergo hydrolysis reaction in the aqueous solution to generate tin hydroxide or other intermediates. The sulfur source can form a complex with lower solubility or larger particles with tin ions in the solution. Sufficient stirring is a necessary condition for the formation of the complex. The presence of ammonium ions will further change the ionic strength and pH value of the solution, further promoting the hydrolysis reaction of tin ions and the formation of the complex, thereby obtaining a milky white solution.

[0030] In one embodiment, the molar ratio of molybdenum element, sulfur element and tin element in the molybdenum source, sulfur source and tin source is (3.5-10.5):(20-40):(1.0~2.5); more preferably, the molybdenum source is ammonium molybdate tetrahydrate with a concentration of 0.5~1.5 mmol / L, the sulfur source is thiourea with a concentration of 20~40 mmol / L, and the tin source is tin tetrachloride pentahydrate with a concentration of 1.0~2.5 mmol / L.

[0031] In one embodiment, the continuous stirring time is 15-25 minutes, more preferably 20 minutes.

[0032] Step S2, subjecting the mixed solution of step S1 to ultrasonic pre-reaction to make the molybdenum source and the tin source fully contact to obtain a uniform light gray-blue precursor solution, and then continuing to stir at room temperature for 5 to 10 minutes; In one implementation manner, the continuous stirring time is 5 to 10 minutes. In this embodiment, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, and 10 minutes can be selected.

[0033] In one implementation manner, the ultrasonic power is 60-180 W. In this embodiment, 60 W, 70 W, 80 W, 100 W, 150 W, and 180 W can be selected. The ultrasonic time is 30-60 min. In this embodiment, 30 min, 40 min, 45 min, 50 min, 55 min, and 60 min can be selected.

[0034] Ultrasound promotes the rapid mixing and complexation of solutes, provides more reaction interfaces, and reduces the particle generation of tin hydroxide or other intermediates; ultrasound also promotes the conversion of molybdenum-tin-sulfur complexes into precursors that can form molybdenum disulfide / tin dioxide heterojunctions through local high temperature and high pressure environments. Continuous ultrasound also changes its electronic structure, thereby forming a light gray-blue solution. Ultrasound allows sufficient contact between solutes, making the precursor more uniform, and the sufficient complexation of molybdenum and tin sources also provides the necessary conditions for the formation of 1T phase molybdenum disulfide, thereby improving the yield and purity of the heterojunction.

[0035] Step S3: placing the precursor solution in a reaction kettle and reacting at high temperature for a period of time.

[0036] In one embodiment, the reaction temperature is 180-220° C., preferably 200° C., and in this embodiment, 180° C., 190° C., 200° C., 210° C., and 220° C. can be selected. The heating time is 18-24 h, and in this embodiment, 18 h, 19 h, 20 h, 22 h, and 24 h can be selected.

[0037] High temperature heating provides the necessary conditions for the formation of heterojunction, 1T-MoS 2 Nanosheets can effectively load tin dioxide particles. This structure can not only avoid the agglomeration of nanosheets during the charge and discharge process, but the heterojunction interface can also improve the migration efficiency of lithium-ion batteries.

[0038] Step S4, washing, drying and naturally cooling the mixture heated in step S3 to obtain a 1T phase molybdenum disulfide / tin dioxide composite material.

[0039] In one embodiment, the cleaning is performed with deionized water and ethanol for 3 times.

[0040] In one implementation manner, the drying temperature is 50-80° C. and the drying time is 8-16 h.

[0041] This embodiment also provides a 1T phase molybdenum disulfide / tin dioxide heterojunction material (1T-MoS 2 / SnO 2 Heterojunction) is prepared by the above method. 2 / SnO 2 The heterojunction interface formed in the heterojunction material can effectively promote the transmission of lithium ions. The gaps between the ultra-thin nanosheets can effectively alleviate the volume expansion during the reaction process. The formation of the heterojunction interface can increase the transmission rate of lithium ions. 2 The electronic conductivity of heterojunction materials can be improved, and the exposed edge sites can accelerate the redox reaction kinetics of polysulfides.

[0042] This embodiment also provides an application of a 1T phase molybdenum disulfide / tin dioxide heterojunction material in preparing a battery material, wherein the battery material is a negative electrode material for a sodium ion battery or a catalyst material for a positive electrode of a lithium sulfur battery.

[0043] The positive electrode material of the lithium-sulfur battery is obtained by a conventional slurry coating method. The positive electrode material of the lithium-sulfur battery has good conductivity and low volume expansion rate, can effectively inhibit the shuttle effect, and can significantly improve the electrochemical performance, cycle performance and service life of the battery. In the long cycle process at a current density of 2 C, the material shows a relatively stable performance.

[0044] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0045] Embodiment 1: First, 618 mg of ammonium molybdate tetrahydrate (0.5 mmol), 2283 mg of thiourea (30 mmol), and 526 mg of tin tetrachloride pentahydrate (1.7 mmol) were dissolved in 65 ml of water to obtain a milky white mixed solution, which was continuously stirred for 20 min. Ultrasonic pre-reaction was then performed to allow the molybdenum source and the tin source to fully contact, obtaining a uniform light gray-blue precursor solution, which was then continuously stirred at room temperature for 10 min. The light gray-blue precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, the reactants were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain 1T MoS 2 / SnO 2 Heterojunction materials.

[0046] Figure 1 1T-MoS prepared in Example 1 of the present invention 2 / SnO 2 SEM and TEM images of heterojunction materials, where Figure 1 (a) is a 20µm SEM image. Figure 1 (b) is a 400nm SEM image. Figure 1 (c) is the 10nm TEM image.

[0047] Figure 2 1T-MoS prepared in Example 1 of the present invention 2 / SnO 2 XRD patterns of heterojunction materials.

[0048] The 1T-MoS2 / SnO2 heterojunction material prepared in Example 1 of the present invention is mixed with sulfur in a ratio of 1:3 and used as the positive electrode material of a lithium-sulfur battery. The positive electrode sheet is obtained by conventional slurry stirring, coating, drying and cutting methods. Subsequently, lithium metal is used as the negative electrode in the glove phase to assemble a lithium-sulfur battery. Figure 3 shows that in terms of long cycle performance, the capacity of the battery does not decay rapidly with the increase in the number of cycles. Within the first few hundred cycles, the capacity remains at a high level, indicating that the material can maintain a good working state during multiple charge and discharge processes and has good cycle stability. This is due to the fact that 1T-MoS 2 / SnO 2The heterojunction structure can effectively alleviate the volume change of the positive electrode during the charge and discharge process and reduce the capacity loss caused by structural damage. At the same time, the heterojunction interface promotes the transmission of lithium ions, ensures the efficient migration of ions during the charge and discharge process of the battery, and maintains a high capacity. In terms of coulombic efficiency, the coulombic efficiency remains at a high level, close to 100%, throughout the cycle. This means that during the charge and discharge process, the battery has a high charge transfer efficiency and fewer side reactions. The material can effectively use the input electrical energy for chemical reactions, reducing energy loss. Highly conductive 1T-MoS 2 The electronic conductivity of the heterojunction material is improved, and the exposed edge sites accelerate the redox reaction kinetics of polysulfides, allowing the battery to react more efficiently during the charge and discharge process, thereby maintaining a high coulombic efficiency.

[0049] Embodiment 2: First, 618 mg of ammonium molybdate tetrahydrate, 2283 mg of thiourea, and 600 mg of tin tetrachloride pentahydrate were dissolved in 65 ml of water to obtain a milky white mixed solution, which was continuously stirred for 15 min. Ultrasonic pre-reaction was then performed to allow the molybdenum source and the tin source to fully contact, obtaining a uniform light gray-blue precursor solution, which was then continuously stirred at room temperature for 10 min. The light gray-blue precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, the reactants were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain 1T MoS 2 / SnO 2 The SEM and XRD patterns of the heterojunction material are as shown in Example 1.

[0050] The 1T-MoS prepared in Example 2 of the present invention 2 / SnO 2 After the heterojunction material and sulfur were mixed in a ratio of 1:3, the positive electrode sheet was obtained by conventional methods of slurry stirring, scraping, drying and cutting. Then, lithium metal was used as the negative electrode in the glove phase to assemble the lithium-sulfur battery. The battery still had a capacity of 380 mAh g after 200 charge and discharge cycles at a current density of 2 C. -1 The specific capacity is similar to that of Example 1.

[0051] Embodiment 3: First, 618 mg of ammonium molybdate tetrahydrate, 2283 mg of thiourea, and 500 mg of tin tetrachloride pentahydrate were dissolved in 65 ml of water to obtain a milky white mixed solution, which was continuously stirred for 25 min. Ultrasonic pre-reaction was then performed to allow the molybdenum source and the tin source to fully contact, thereby obtaining a uniform light gray-blue precursor solution, which was then continuously stirred at room temperature for 5 min. The light gray-blue precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, the reactants were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain 1T MoS 2 / SnO 2 The SEM and XRD patterns of the heterojunction material are as shown in Example 1.

[0052] The 1T-MoS2 / SnO2 heterojunction material prepared in Example 3 of the present invention was mixed with sulfur in a ratio of 1:3, and used as the positive electrode material of the lithium-sulfur battery, and the positive electrode sheet was obtained by conventional slurry stirring, scraping, drying, and cutting methods. Subsequently, lithium metal was used as the negative electrode in the glove phase to assemble the lithium-sulfur battery. During the long cycle of the battery at a current density of 2 C, the heterojunction material showed relatively stable performance as in Example 1.

[0053] Embodiment 4: First, 618 mg of ammonium molybdate tetrahydrate, 2283 mg of thiourea, 1.5 mmol / L concentration, 400 mg of tin tetrachloride pentahydrate and 65 ml of water were added to obtain a milky white mixed solution, which was continuously stirred for 20 min. Ultrasonic pre-reaction was then performed to allow the molybdenum source and the tin source to fully contact, obtaining a uniform light gray-blue precursor solution, which was then continuously stirred at room temperature for 8 min. The light gray-blue precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, the reactants were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain 1T MoS 2 / SnO 2 The SEM and XRD patterns of the heterojunction material are as shown in Example 1.

[0054] The 1T-MoS2 / SnO2 heterojunction material prepared in Example 4 of the present invention was mixed with sulfur in a ratio of 1:3, and used as the positive electrode material of the lithium-sulfur battery, and the positive electrode sheet was obtained by conventional slurry stirring, scraping, drying, and cutting methods. Subsequently, lithium metal was used as the negative electrode in the glove phase to assemble the lithium-sulfur battery. During the long cycle of the battery at a current density of 2 C, the heterojunction material showed relatively stable performance as in Example 1.

[0055] Embodiment 5: First, 550 mg of ammonium tetramolybdate, 2283 mg of thiourea, and 526 mg of tin tetrachloride pentahydrate were dissolved in 65 ml of water to obtain a milky white mixed solution, which was continuously stirred for 20 min. Ultrasonic pre-reaction was then performed to allow the molybdenum source and the tin source to fully contact, obtaining a uniform light gray-blue precursor solution, which was then continuously stirred at room temperature for 10 min. The light gray-blue precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, the reactants were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain 1T MoS 2 / SnO 2 The SEM and XRD patterns of the heterojunction material are as shown in Example 1.

[0056] The 1T-MoS2 / SnO2 heterojunction material prepared in Example 5 of the present invention was mixed with sulfur in a ratio of 1:3, and used as the positive electrode material of the lithium-sulfur battery, and the positive electrode sheet was obtained by conventional slurry stirring, scraping, drying, and cutting methods. Subsequently, lithium metal was used as the negative electrode in the glove phase to assemble the lithium-sulfur battery. During the long cycle of the battery at a current density of 2 C, the heterojunction material showed relatively stable performance as in Example 1.

[0057] Embodiment 6: First, 618 mg of ammonium molybdate tetrahydrate, 1000 mg of sodium thiosulfate, and 526 mg of tin tetrachloride pentahydrate were dissolved in 65 ml of water to obtain a milky white mixed solution, which was continuously stirred for 20 min; then, an ultrasonic pre-reaction was performed to allow the molybdenum source and the tin source to fully contact to obtain a uniform light gray-blue precursor solution, which was then continuously stirred at room temperature for 10 min; The light gray-blue precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, the reactants were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain 1T MoS 2 / SnO 2The SEM and XRD patterns of the heterojunction material are as shown in Example 1.

[0058] The 1T-MoS2 / SnO2 heterojunction material prepared in Example 6 of the present invention was mixed with sulfur in a ratio of 1:3, and used as a positive electrode material for a lithium-sulfur battery, and a positive electrode sheet was obtained by conventional slurry stirring, coating, drying, and cutting methods. Subsequently, lithium metal was used as a negative electrode in the glove phase to assemble a lithium-sulfur battery. During the long cycle of the battery at a current density of 2 C, the heterojunction material showed relatively stable performance as in Example 1.

[0059] Comparative Example 1: First, 618 mg of ammonium molybdate tetrahydrate, 2283 mg of thiourea, and 526 mg of tin tetrachloride pentahydrate were dissolved in 65 ml of water to obtain a milky white mixed solution, which was stirred for 30 min. The precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, the reactants were placed in a vacuum drying oven and dried at 60 degrees for 12 hours to obtain the MoS2 / SnO2 heterojunction material. The XRD results are shown in Figure 2. Figure 4 shown.

[0060] Comparative Example 2: First, 850 mg of sodium molybdate dihydrate, 2283 mg of thiourea, and 526 mg of tin tetrachloride pentahydrate were dissolved in 65 ml of water to obtain a mixed solution, which was continuously stirred for 20 min; then an ultrasonic pre-reaction was performed, and then stirring was continued at room temperature for 10 min; The precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, they were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain MoS 2 / SnO 2 Materials, their XRD results are similar to Figure 4 Consistent.

[0061] Comparative Example 3: First, 2283 mg of thiourea and 500 mg of tin tetrachloride pentahydrate were dissolved in 65 ml of water and stirred for 25 min. Then, ultrasonic pre-reaction was performed and stirring was continued at room temperature for 5 min. The precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, they were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain SnS2 Material. Figure 5 The SnS prepared in Comparative Example 3 of the present invention 2 XRD pattern of .

[0062] Comparative Example 4: First, 618 mg of ammonium molybdate tetrahydrate and 2283 mg of thiourea were dissolved in 65 ml of water and stirred for 25 min. Then, ultrasonic pre-reaction was performed and stirring was continued at room temperature for 5 min. The precursor solution was placed in a reactor and stirred thoroughly. The reactor was then placed in a forced air drying oven and heated to 200 degrees for 24 hours. The reactants were then taken out and washed with deionized water and ethanol for three times. Finally, they were placed in a vacuum drying oven at 60 degrees for 12 hours to obtain MoS 2 material. Figure 6 The MoS prepared in Comparative Example 4 of the present invention 2 : The XRD pattern of 2H phase molybdenum disulfide.

[0063] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A one-step method for preparing 1T phase molybdenum disulfide / tin dioxide heterojunction material, characterized in that The method comprises the following steps: Dissolve a molybdenum source, a sulfur source, and a tin source in deionized water under continuous stirring at room temperature to obtain a milky white mixed solution, and continue to stir continuously; the molybdenum source contains ammonium radicals; the tin source is at least one of tin tetrachloride pentahydrate and tin chloride; The milky white mixed solution was subjected to ultrasonic pre-reaction to allow the molybdenum source and the tin source to fully contact each other to obtain a uniform light gray-blue precursor solution, and the mixture was stirred at room temperature; The light gray-blue precursor solution is placed in a reaction kettle and reacted at 180-220°C for a period of time; The heated product is washed, dried, and naturally cooled to obtain a 1T phase molybdenum disulfide / tin dioxide heterojunction material.

2. The method according to claim 1, characterized in that: The molybdenum source is at least one of ammonium molybdate tetrahydrate and ammonium tetramolybdate.

3. The method according to claim 1, characterized in that: The sulfur source is at least one of thiourea, sodium thiosulfate and sodium sulfite.

4. The method according to claim 1, characterized in that: The milky white mixed solution is continuously stirred for 20 minutes, and the light gray-blue precursor solution is continuously stirred for 5 to 10 minutes.

5. The method according to claim 1, characterized in that: The light gray-blue precursor solution is heated in the reactor for 18 to 24 hours.

6. The method according to claim 1, characterized in that: The molybdenum source is ammonium molybdate tetrahydrate with a concentration of 0.5-1.5 mmol / L, the sulfur source is thiourea with a concentration of 20-40 mmol / L, and the tin source is tin tetrachloride pentahydrate with a concentration of 1.0-2.5 mmol / L.

7. The method according to claim 1, characterized in that: The ultrasonic power of the milky white mixed solution during ultrasonic pre-reaction is 60-180 W, and the ultrasonic time is 30-60 min.

8. The method according to claim 1, characterized in that: The light gray-blue precursor solution was heated at a temperature of 200° C. in a reactor for 24 h.

9. A 1T phase molybdenum disulfide / tin dioxide heterojunction material prepared by the method according to any one of claims 1 to 8.

10. Use of a 1T phase molybdenum disulfide / tin dioxide heterojunction material according to claim 9 in preparing battery materials, characterized in that The battery material is a negative electrode material for a sodium ion battery or a catalyst material for a positive electrode of a lithium sulfur battery.

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