Molybdenum telluride hollow nanospheres and a method for preparing the same

Abstract

The application discloses a kind of molybdenum telluride hollow nanospheres and preparation method thereof, belong to secondary battery electrode material preparation and the sustainable development field of environment and energy source.The preparation method of the molybdenum telluride hollow nanospheres of the application, the raw material used is industrial grade product, molybdenum telluride hollow nanospheres are synthesized by hydrothermal method in combination with calcination method, reaction process is simple, energy consumption is lower, environment is friendly, is suitable for low-cost scale production.The preparation method of the application, the size of molybdenum telluride hollow nanospheres can be regulated by changing reaction parameters, the molybdenum telluride hollow nanospheres prepared are stable in appearance, not agglomerated, high in purity, high in crystallinity.As secondary battery electrode material, it has good electrochemical performance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of secondary battery electrode material preparation, and particularly relates to a molybdenum telluride hollow nanosphere and a preparation method thereof. BACKGROUND

[0002] Conventional catalysts are often limited by their low catalytic activity. Therefore, finding inexpensive and effective catalysts has become a top priority.

[0003] Transition metal dichalcogenides (TMDs) have played an irreplaceable role in energy storage, catalysis, sensing, optoelectronic devices and many other fields due to their special catalytic and electronic properties. In particular, it is the goal of many researchers to prepare transition metal dichalcogenides with high specific surface area, multiple defects and uniform morphology and size.

[0004] For materials with the same composition and size, the surface area of hollow nanostructure is larger than that of bulk structure, and its density is relatively low. Therefore, whether as a carrier or a catalyst, hollow micro-nano structure has broad application prospects.

[0005] Molybdenum telluride is a type of transition metal dichalcogenide, which has unique mechanical properties, electrical properties and optical properties. In addition, molybdenum telluride is also a semiconductor with a band gap close to Si (~ 1.0 eV), and has unique phase change characteristics. Therefore, molybdenum telluride has wide application prospects in the fields of photoelectric catalysis, environment, energy and the like. The existing methods for preparing molybdenum telluride nanomaterials include liquid phase exfoliation method, mechanical exfoliation method, vapor deposition method, electrochemical deposition method and the like. However, the above preparation methods usually have the disadvantages of complex reaction, high energy consumption, easy introduction of impurities and difficulty in large-scale preparation. SUMMARY

[0006] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a molybdenum telluride hollow nanosphere and a preparation method thereof, so as to solve the technical problems of the existing preparation methods, such as complex reaction, high energy consumption, easy introduction of impurities and difficulty in large-scale preparation.

[0007] In order to achieve the above-mentioned purpose, the following technical solutions are adopted in the present application:

[0008] The application discloses a preparation method of a molybdenum telluride hollow nanosphere, comprising the following steps:

[0009] S1: dissolve tannic acid, amino-tris (hydroxymethyl) aminomethane and polystyrene in deionized water, stir and react, collect the obtained product, and after water washing, drying and calcination, product A is obtained;

[0010] S2: dispersing the product A and ammonium molybdate into deionized water to obtain a mixed solution; subjecting the mixed solution to hydrothermal reaction to obtain a reaction product; and subjecting the reaction product to water washing, drying and calcination in sequence to obtain product B;

[0011] S3: mixing the product B and tellurium powder and then calcining to obtain the molybdenum telluride hollow nanospheres.

[0012] Further, in S1, the tannic acid, tromethamine, polystyrene and deionized water are used in a mass ratio of 1:(0.1-0.3):(1-3):50.

[0013] Further, in S1, the stirring is carried out at normal temperature and pressure for 7-10 h.

[0014] Further, in S1, the water washing is carried out for 3-4 times; and the calcination is carried out at 800-900 DEG C in an argon atmosphere for 1-2 h.

[0015] Further, in S2, the product A, ammonium molybdate and deionized water are used in a mass ratio of 1:(1-3):100; the hydrothermal reaction is carried out at a temperature of 180-200 DEG C for 10-12 h.

[0016] Further, in S1 and S2, the drying is carried out at 50-70 DEG C for 6-8 h.

[0017] Further, in S2, the calcination is carried out at 500-600 DEG C in air for 1-2 h.

[0018] Further, in S3, the product B and tellurium powder are used in a mass ratio of 1:(4-6); and the calcination is carried out at 750-850 DEG C in an argon atmosphere for 2-4 h.

[0019] The application further discloses the molybdenum telluride hollow nanospheres prepared by the preparation method.

[0020] Further, the molybdenum telluride hollow nanospheres have an outer diameter of 0.8 μm and a spherical wall thickness of 60 nm.

[0021] Compared with the prior art, the application has the following beneficial effects:

[0022] The application discloses a preparation method of molybdenum telluride hollow nanospheres, which adopts industrial products such as tannic acid, tromethamine, polystyrene and tellurium powder as raw materials, and first synthesizes the molybdenum telluride hollow nanospheres through a hydrothermal method combined with a calcination method.

[0023] The application further discloses the molybdenum telluride hollow nanospheres prepared by the preparation method, and the hollow ball structure is favorable for full contact of electrolyte and active material, the unique structure provides a theoretical basis and practical experience for wide application of the micro-nano material in the fields of energy storage and catalysis, and the molybdenum telluride hollow nanospheres have excellent prospects in the field of secondary battery electrode materials. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A transmission electron microscope image of the molybdenum telluride hollow nanospheres prepared in Example 1;

[0025] Figure 2 An XRD image of the molybdenum telluride hollow nanospheres prepared in Example 1;

[0026] Figure 3 A charge-discharge graph of the molybdenum telluride hollow nanospheres prepared in Example 1. DETAILED DESCRIPTION

[0027] To enable persons skilled in the art to understand the features and effects of the present application, the following is a general description and definition of the terms and phrases mentioned in the specification and claims. Unless otherwise specified, all technical and scientific words used in the specification are the usual meanings understood by those skilled in the art of the present application, and in the event of conflict, the definition in the specification shall prevail.

[0028] Theories or mechanisms described and disclosed herein, whether correct or not, should not be used to limit the scope of the present application, that is, the content of the present application can be implemented without being limited by any particular theory or mechanism.

[0029] In this paper, all the characteristics defined in the form of numerical range or percentage range, such as numerical value, quantity, content and concentration, are only for the sake of brevity and convenience. Therefore, the description of numerical range or percentage range should be considered to have covered and specifically disclosed all possible sub-ranges and individual numerical values (including integers and fractions) within the range.

[0030] In this document, "include," "includes," "including," "comprise," "comprises," "comprising," "have," "has," "having," or the like are used inclusively, in a non- restrictive sense, and encompass the terms "consisting of" and "consisting essentially of," unless otherwise stated. For example, "A includes a" encompasses the meanings of "A includes a and other" and "A includes only a."

[0031] In this document, all possible combinations of the various features described in the various embodiments or examples are not described. Therefore, the various features in the various embodiments or examples can be combined in any manner, as long as the combination of the features does not contradict, and all possible combinations are considered to be within the scope of the present specification.

[0032] The present application is further described in detail by reference to specific examples. It is understood that these examples are for illustrative purposes only and are not intended to limit the scope of this application. It is also understood that various modifications can be made by those skilled in the art within the scope of the present application, which is defined by the appended claims.

[0033] The following examples use conventional equipment in the art. The experimental methods in the following examples, unless otherwise specified, are generally carried out under conventional conditions, or under conditions recommended by the manufacturer. In the following examples, various raw materials are used, unless otherwise specified, conventional commercially available products are used, and the specifications are conventional specifications in the art. In the specification of the present application and in the following examples, unless otherwise specified, "%" means weight percent, "parts" means weight parts, and the ratio means weight ratio.

[0034] Example 1

[0035] A method for preparing a molybdenum telluride hollow nanosphere, comprising the following steps:

[0036] S1: 1 part of tannic acid, 0.3 parts of tromethamine and 3 parts of polystyrene were dissolved in 50 parts of deionized water, stirred at room temperature and normal pressure for 7 h, and then the product was collected, washed with water for 3 times, dried at 50°C for 6 h, and calcined at 800°C in an argon atmosphere for 1 h to obtain product A;

[0037] S2: Then 1 part of product A and 3 parts of ammonium molybdate were dispersed in 100 parts of deionized water, and hydrothermal reaction was carried out at 180°C for 12 h. After the reaction was completed, the product was collected, washed with water for 4 times, dried at 70°C for 8 h, and calcined at 500°C in air for 1 h to obtain product B;

[0038] S3: 1 part of product B and 6 parts of tellurium powder were placed in a tube furnace and calcined at 850°C in an argon atmosphere for 2 h to obtain a molybdenum telluride hollow nanosphere.

[0039] Reference is made toFigure 1 Figure 1 A transmission electron microscope image of the prepared molybdenum telluride hollow nanospheres, wherein the prepared product has a diameter of 0.8 μm and a thickness of 60 nm.

[0040] Referring to Figure 2 Figure 2 An XRD image of the prepared product, and it can be determined from the XRD image that the phase composition is MoTe2, corresponding to JCPDS card No. 71-2157.

[0041] Referring to Figure 3 Figure 3 A charge-discharge graph of the molybdenum telluride hollow nanospheres as a negative electrode material of a sodium ion battery is given, wherein the discharge specific capacity and the charge specific capacity are 319 mAh / g and 251 mAh / g, respectively, at a current density of 100 mA / g.

[0042] The present application completes the preparation of molybdenum telluride by using cheap and readily available raw materials and simple and efficient preparation conditions, and obtains a nanoscale hollow spherical morphology. The present application provides a good theoretical basis and practical experience for the design and synthesis of molybdate micro-nano materials.

[0043] Example 2

[0044] A preparation method of molybdenum telluride hollow nanospheres comprises the following steps:

[0045] S1: 1 part of tannic acid, 0.1 part of tromethamine and 1 part of polystyrene are dissolved in 50 parts of deionized water, stirred at room temperature and normal pressure for 7 h, and then the product is collected, washed with water for 4 times, dried at 70 DEG C for 7 h, calcined at 900 DEG C in an argon atmosphere for 2 h, and then product A is obtained;

[0046] S2: Then 1 part of product A and 1 part of ammonium molybdate are dispersed into 100 parts of deionized water, and hydrothermal reaction is carried out at 200 DEG C for 10 h, and then the product is collected, washed with water for 4 times, dried at 70 DEG C for 8 h, calcined in air at 600 DEG C for 2 h, and then product B is obtained;

[0047] S3: 1 part of product B and 4 parts of tellurium powder are placed in a tube furnace, and calcined at 750 DEG C in an argon atmosphere for 4 h, and then a molybdenum telluride hollow nanosphere is obtained.

[0048] Example 3

[0049] A preparation method of molybdenum telluride hollow nanospheres comprises the following steps:

[0050] ​​​S1: 1 part of tannic acid, 0.2 part of tromethamine and 2 parts of polystyrene are dissolved in 50 parts of deionized water in mass fraction, stirred at room temperature and normal pressure for 8 h, and then the product is collected, washed with water for 3 times, dried at 80°C for 8 h, calcined at 800°C in argon atmosphere for 2 h to obtain product A;

[0051] S2: 1 part of product A and 2 parts of ammonium molybdate are then dispersed in 100 parts of deionized water, and hydrothermal reaction is carried out at 190°C for 11 h, and then the product is collected, washed with water for 4 times, dried at 70°C for 8 h, calcined at 550°C in air for 2 h to obtain product B;

[0052] S3: 1 part of product B and 5 parts of tellurium powder are placed in a tube furnace and calcined at 800°C in argon atmosphere for 3 h to obtain a molybdenum telluride hollow nanosphere.

[0053] Example 4

[0054] A preparation method of a molybdenum telluride hollow nanosphere, comprising the following steps:

[0055] S1: 1 part of tannic acid, 0.2 part of tromethamine and 2 parts of polystyrene are dissolved in 50 parts of deionized water in mass fraction, stirred at room temperature and normal pressure for 8 h, and then the product is collected, washed with water for 3 times, dried at 80°C for 8 h, calcined at 800°C in argon atmosphere for 2 h to obtain product A;

[0056] S2: 1 part of product A and 2 parts of ammonium molybdate are then dispersed in 100 parts of deionized water, and hydrothermal reaction is carried out at 190°C for 11 h, and then the product is collected, washed with water for 4 times, dried at 70°C for 8 h, calcined at 550°C in air for 2 h to obtain product B;

[0057] S3: 1 part of product B and 5 parts of tellurium powder are placed in a tube furnace and calcined at 800°C in argon atmosphere for 3 h to obtain a molybdenum telluride hollow nanosphere.

[0058] Example 5

[0059] A preparation method of a molybdenum telluride hollow nanosphere, comprising the following steps:

[0060] S1: 1 part of tannic acid, 0.2 part of tromethamine and 2 parts of polystyrene are dissolved in 50 parts of deionized water in mass fraction, stirred at room temperature and normal pressure for 8 h, and then the product is collected, washed with water for 3 times, dried at 80°C for 8 h, calcined at 800°C in argon atmosphere for 2 h to obtain product A;

[0061] S2: Then 1 part of product A and 3 parts of ammonium molybdate are dispersed into 100 parts of deionized water, and hydrothermal reaction is carried out at 180℃ for 10h, after the reaction, the product is collected, washed with water for 4 times, dried at 70℃ for 8h, and calcined in air at 550℃ for 2h, to obtain product B;

[0062] S3: 1 part of product B and 5 parts of tellurium powder are placed into a tube furnace, and calcined at 750℃ for 2h under argon atmosphere, to obtain a molybdenum telluride hollow nanosphere.

[0063] The above is only to illustrate the technical idea of the present application, and cannot limit the protection scope of the present application, any modification made according to the technical idea of the present application on the basis of the technical scheme, falls into the protection scope of the present application claim.

Claims

1. A method for preparing hollow nanospheres of molybdenum telluride, characterized in that, The method comprises the following steps: S1: dissolving tannic acid, tromethamine and polystyrene in deionized water, stirring to react, collecting the reaction product, and obtaining product A after water washing, drying and calcination; S2: dispersing product A and ammonium molybdate in deionized water to obtain a mixed solution; performing hydrothermal reaction on the mixed solution to obtain a reaction product; and obtaining product B after water washing, drying and calcination in sequence; S3: mixing product B and tellurium powder, and then calcining to obtain molybdenum telluride hollow nanospheres; The amount ratio of tannic acid, tromethamine, polystyrene and deionized water is 1: (0.1-0.3): (1-3):

50. In S2, the amount ratio of product A, ammonium molybdate and deionized water is 1: (1-3): 100 by mass fraction; the hydrothermal reaction temperature is 180-200℃, and the time is 10-12h.

2. The method for preparing molybdenum telluride hollow nanospheres according to claim 1, characterized in that, In S1, the stirring is performed at normal temperature and pressure for 7-10h.

3. The method for preparing molybdenum telluride hollow nanospheres according to claim 1, characterized in that, In S1, the water washing is performed for 3-4 times; and the calcination is performed at 800-900℃ in an argon atmosphere for 1-2h.

4. The method for preparing molybdenum telluride hollow nanospheres according to claim 1, characterized in that, In S1 and S2, the drying is performed at 50-70℃ for 6-8h.

5. The method for preparing molybdenum telluride hollow nanospheres according to claim 1, characterized in that, In S2, the calcination is performed at 500-600℃ in air for 1-2h.

6. The method of claim 1, wherein the MoTe2 hollow nanospheres are prepared by the following steps of: In S3, the amount ratio of product B and tellurium powder is 1: (4-6) by mass fraction; and the calcination is performed at 750-850℃ in an argon atmosphere for 2-4h.

7. A hollow nanosphere of molybdenum telluride, characterized in that, The molybdenum telluride hollow nanospheres are prepared by the method of any one of claims 1-6.

8. The hollow MoTe nanospheres according to claim 7, wherein, The outer diameter of the molybdenum telluride hollow nanospheres is 0.8μm, and the wall thickness is 60nm.

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