MOLYBDENUM DISULFIDE/GRAPHENE/CARBON COMPOSITE MATERIAL AND USE THEREOF

Abstract

A molybdenum disulfide/graphene/carbon composite material having a hierarchical pore structure includes a composite nanofiber having a diameter of 60 to 500 nm. The composite nanofiber comprises, in mass percentage, 3% to 35% of molybdenum disulfide, 0.2% to 10% of graphene, and 60% to 95% of carbon. The composite nanofiber has a hierarchical pore structure distributed along the axial direction, and has a pore diameter continuously distributed between 0.1 nm and 5 μm and an average pore diameter between 1.5 nm and 25 nm. On the basis of the pore volume, in the hierarchical pore structure, a micropore structure accounts for 25% to 60%, and a mesoporous structure accounts for 40% to 75%. The microporous structure is distributed on the surface of the nanofiber and the pore wall of the mesoporous structure.

Claims

1. A molybdenum disulfide/graphene/carbon composite material, wherein the molybdenum disulfide/graphene/carbon composite material is composed of a composite nanofiber with a diameter of 60 nm to 500 nm; in a mass percentage, the composite nanofiber comprises 3% to 35% of molybdenum disulfide, 0.2% to 10% of graphene, and 60% to 95% of carbon; and the composite nanofiber has a hierarchical pore structure distributed along an axial direction.

2. The molybdenum disulfide/graphene/carbon composite material according to claim 1, wherein the molybdenum disulfide and the graphene both are uniformly dispersed as a monolayer structure in the composite nanofiber based on a carbon nanofiber.

3. The molybdenum disulfide/graphene/carbon composite material according to claim 1, wherein the hierarchical pore structure has a pore diameter continuously distributed between 0.1 nm and 5 μm, and an average pore diameter of the hierarchical pore structure is 1.5 nm to 25 nm.

4. The molybdenum disulfide/graphene/carbon composite material according to claim 1, wherein based on a pore volume, in the hierarchical pore structure, a microporous structure accounts for 25% to 60% and a mesoporous structure accounts for 40% to 75%.

5. The molybdenum disulfide/graphene/carbon composite material according to claim 4, wherein the microporous structure is distributed on a surface of the composite nanofiber and a pore wall of the mesoporous structure.

6. The molybdenum disulfide/graphene/carbon composite material according to claim 1, wherein the molybdenum disulfide/graphene/carbon composite material has a specific surface area of 500 m.sup.2/g to 3,200 m.sup.2/g.

7. The molybdenum disulfide/graphene/carbon composite material according to claim 1, wherein the composite material is prepared by the following method: (1) adding 0.6 g to 1.5 g of polyacrylonitrile, 0.5 g to 1.2 g of polyvinylpyrrolidone, 0.2 g to 1.0 g of ammonium tetrathiomolybdate, and 0.05 g to 0.2 g of graphene to 10 g to 16 g of N,N-dimethylformamide, stirring a resulting solution for dissolution, and filtering the resulting solution through a 400-mesh stainless steel mesh to obtain a filtrate for later use; (2) taking an appropriate amount of the filtrate to conduct an electrostatic spinning to obtain a composite fiber film; (3) placing the composite fiber film in a tube furnace, and in a N.sub.2/H.sub.2 mixed atmosphere with a volume ratio of 9/1, heating the tube furnace to a temperature of 380° C. to 450° C. at a heating rate of 2° C./min to 6° C./min, holding the temperature for 1 hour to 6 hours, cooling the tube furnace to room temperature, and taking a treated composite fiber film out; (4) preparing a KOH saturated solution, subjecting the treated composite fiber film to an ultrasonic treatment in the KOH saturated solution for 1 hour and a static impregnation for 48 hours in the KOH saturated solution, and vacuum-drying an impregnated composite fiber film for 8 hours to obtain a dried composite fiber film, wherein a mass ratio of the treated composite fiber film to KOH is 1:(0.4-10); and (5) placing the dried composite fiber film in the tube furnace, and in an argon atmosphere, heating the tube furnace to 750° C. to 850° C. at a heating rate of 2° C./min to 10° C./min to conduct a high-temperature activation for 1 hour to 16 hours, cooling the tube furnace to room temperature, and taking a product out; and washing the product with a dilute hydrochloric acid solution, and vacuum-drying a washed product for 10 hours to obtain the molybdenum disulfide/graphene/carbon composite material with the hierarchical pore structure.

8. The molybdenum disulfide/graphene/carbon composite material according to claim 7, wherein the electrostatic spinning in step (2) is conducted at room temperature for 2 hours to 10 hours under the following parameters to obtain the composite fiber film: a spinning voltage of 20 kV, an advancing speed of 0.015 mL/min, a spinning receiving distance of 18 cm, and a syringe needle of 8 #.

9. Use of the molybdenum disulfide/graphene/carbon composite material according to claim 1 in fields comprising lithium-ion battery negative electrode materials, supercapacitor electrode materials, catalytic materials for hydrogen production by water electrolysis, and mercury adsorption materials.

10. The molybdenum disulfide/graphene/carbon composite material according to claim 2, wherein the composite material is prepared by the following method: (1) adding 0.6 g to 1.5 g of polyacrylonitrile, 0.5 g to 1.2 g of polyvinylpyrrolidone, 0.2 g to 1.0 g of ammonium tetrathiomolybdate, and 0.05 g to 0.2 g of graphene to 10 g to 16 g of N,N-dimethylformamide, stirring a resulting solution for dissolution, and filtering the resulting solution through a 400-mesh stainless steel mesh to obtain a filtrate for later use; (2) taking an appropriate amount of the filtrate to conduct an electrostatic spinning to obtain a composite fiber film; (3) placing the composite fiber film in a tube furnace, and in a N.sub.2/H.sub.2 mixed atmosphere with a volume ratio of 9/1, heating the tube furnace to a temperature of 380° C. to 450° C. at a heating rate of 2° C./min to 6° C./min, holding the temperature for 1 hour to 6 hours, cooling the tube furnace to room temperature, and taking a treated composite fiber film out; (4) preparing a KOH saturated solution, subjecting the treated composite fiber film to an ultrasonic treatment in the KOH saturated solution for 1 hour and a static impregnation for 48 hours in the KOH saturated solution, and vacuum-drying an impregnated composite fiber film for 8 hours to obtain a dried composite fiber film, wherein a mass ratio of the treated composite fiber film to KOH is 1:(0.4-10); and (5) placing the dried composite fiber film in the tube furnace, and in an argon atmosphere, heating the tube furnace to 750° C. to 850° C. at a heating rate of 2° C./min to 10° C./min to conduct a high-temperature activation for 1 hour to 16 hours, cooling the tube furnace to room temperature, and taking a product out; and washing the product with a dilute hydrochloric acid solution, and vacuum-drying a washed product for 10 hours to obtain the molybdenum disulfide/graphene/carbon composite material with the hierarchical pore structure.

11. The molybdenum disulfide/graphene/carbon composite material according to claim 3, wherein the composite material is prepared by the following method: (1) adding 0.6 g to 1.5 g of polyacrylonitrile, 0.5 g to 1.2 g of polyvinylpyrrolidone, 0.2 g to 1.0 g of ammonium tetrathiomolybdate, and 0.05 g to 0.2 g of graphene to 10 g to 16 g of N,N-dimethylformamide, stirring a resulting solution for dissolution, and filtering the resulting solution through a 400-mesh stainless steel mesh to obtain a filtrate for later use; (2) taking an appropriate amount of the filtrate to conduct an electrostatic spinning to obtain a composite fiber film; (3) placing the composite fiber film in a tube furnace, and in a N.sub.2/H.sub.2 mixed atmosphere with a volume ratio of 9/1, heating the tube furnace to a temperature of 380° C. to 450° C. at a heating rate of 2° C./min to 6° C./min, holding the temperature for 1 hour to 6 hours, cooling the tube furnace to room temperature, and taking a treated composite fiber film out; (4) preparing a KOH saturated solution, subjecting the treated composite fiber film to an ultrasonic treatment in the KOH saturated solution for 1 hour and a static impregnation for 48 hours in the KOH saturated solution, and vacuum-drying an impregnated composite fiber film for 8 hours to obtain a dried composite fiber film, wherein a mass ratio of the treated composite fiber film to KOH is 1:(0.4-10); and (5) placing the dried composite fiber film in the tube furnace, and in an argon atmosphere, heating the tube furnace to 750° C. to 850° C. at a heating rate of 2° C./min to 10° C./min to conduct a high-temperature activation for 1 hour to 16 hours, cooling the tube furnace to room temperature, and taking a product out; and washing the product with a dilute hydrochloric acid solution, and vacuum-drying a washed product for 10 hours to obtain the molybdenum disulfide/graphene/carbon composite material with the hierarchical pore structure.

12. The molybdenum disulfide/graphene/carbon composite material according to claim 4, wherein the composite material is prepared by the following method: (1) adding 0.6 g to 1.5 g of polyacrylonitrile, 0.5 g to 1.2 g of polyvinylpyrrolidone, 0.2 g to 1.0 g of ammonium tetrathiomolybdate, and 0.05 g to 0.2 g of graphene to 10 g to 16 g of N,N-dimethylformamide, stirring a resulting solution for dissolution, and filtering the resulting solution through a 400-mesh stainless steel mesh to obtain a filtrate for later use; (2) taking an appropriate amount of the filtrate to conduct an electrostatic spinning to obtain a composite fiber film; (3) placing the composite fiber film in a tube furnace, and in a N.sub.2/H.sub.2 mixed atmosphere with a volume ratio of 9/1, heating the tube furnace to a temperature of 380° C. to 450° C. at a heating rate of 2° C./min to 6° C./min, holding the temperature for 1 hour to 6 hours, cooling the tube furnace to room temperature, and taking a treated composite fiber film out; (4) preparing a KOH saturated solution, subjecting the treated composite fiber film to an ultrasonic treatment in the KOH saturated solution for 1 hour and a static impregnation for 48 hours in the KOH saturated solution, and vacuum-drying an impregnated composite fiber film for 8 hours to obtain a dried composite fiber film, wherein a mass ratio of the treated composite fiber film to KOH is 1:(0.4-10); and (5) placing the dried composite fiber film in the tube furnace, and in an argon atmosphere, heating the tube furnace to 750° C. to 850° C. at a heating rate of 2° C./min to 10° C./min to conduct a high-temperature activation for 1 hour to 16 hours, cooling the tube furnace to room temperature, and taking a product out; and washing the product with a dilute hydrochloric acid solution, and vacuum-drying a washed product for 10 hours to obtain the molybdenum disulfide/graphene/carbon composite material with the hierarchical pore structure.

13. The molybdenum disulfide/graphene/carbon composite material according to claim 5, wherein the composite material is prepared by the following method: (1) adding 0.6 g to 1.5 g of polyacrylonitrile, 0.5 g to 1.2 g of polyvinylpyrrolidone, 0.2 g to 1.0 g of ammonium tetrathiomolybdate, and 0.05 g to 0.2 g of graphene to 10 g to 16 g of N,N-dimethylformamide, stirring a resulting solution for dissolution, and filtering the resulting solution through a 400-mesh stainless steel mesh to obtain a filtrate for later use; (2) taking an appropriate amount of the filtrate to conduct an electrostatic spinning to obtain a composite fiber film; (3) placing the composite fiber film in a tube furnace, and in a N.sub.2/H.sub.2 mixed atmosphere with a volume ratio of 9/1, heating the tube furnace to a temperature of 380° C. to 450° C. at a heating rate of 2° C./min to 6° C./min, holding the temperature for 1 hour to 6 hours, cooling the tube furnace to room temperature, and taking a treated composite fiber film out; (4) preparing a KOH saturated solution, subjecting the treated composite fiber film to an ultrasonic treatment in the KOH saturated solution for 1 hour and a static impregnation for 48 hours in the KOH saturated solution, and vacuum-drying an impregnated composite fiber film for 8 hours to obtain a dried composite fiber film, wherein a mass ratio of the treated composite fiber film to KOH is 1:(0.4-10); and (5) placing the dried composite fiber film in the tube furnace, and in an argon atmosphere, heating the tube furnace to 750° C. to 850° C. at a heating rate of 2° C./min to 10° C./min to conduct a high-temperature activation for 1 hour to 16 hours, cooling the tube furnace to room temperature, and taking a product out; and washing the product with a dilute hydrochloric acid solution, and vacuum-drying a washed product for 10 hours to obtain the molybdenum disulfide/graphene/carbon composite material with the hierarchical pore structure.

14. The molybdenum disulfide/graphene/carbon composite material according to claim 6, wherein the composite material is prepared by the following method: (1) adding 0.6 g to 1.5 g of polyacrylonitrile, 0.5 g to 1.2 g of polyvinylpyrrolidone, 0.2 g to 1.0 g of ammonium tetrathiomolybdate, and 0.05 g to 0.2 g of graphene to 10 g to 16 g of N,N-dimethylformamide, stirring a resulting solution for dissolution, and filtering the resulting solution through a 400-mesh stainless steel mesh to obtain a filtrate for later use; (2) taking an appropriate amount of the filtrate to conduct an electrostatic spinning to obtain a composite fiber film; (3) placing the composite fiber film in a tube furnace, and in a N.sub.2/H.sub.2 mixed atmosphere with a volume ratio of 9/1, heating the tube furnace to a temperature of 380° C. to 450° C. at a heating rate of 2° C./min to 6° C./min, holding the temperature for 1 hour to 6 hours, cooling the tube furnace to room temperature, and taking a treated composite fiber film out; (4) preparing a KOH saturated solution, subjecting the treated composite fiber film to an ultrasonic treatment in the KOH saturated solution for 1 hour and a static impregnation for 48 hours in the KOH saturated solution, and vacuum-drying an impregnated composite fiber film for 8 hours to obtain a dried composite fiber film, wherein a mass ratio of the treated composite fiber film to KOH is 1:(0.4-10); and (5) placing the dried composite fiber film in the tube furnace, and in an argon atmosphere, heating the tube furnace to 750° C. to 850° C. at a heating rate of 2° C./min to 10° C./min to conduct a high-temperature activation for 1 hour to 16 hours, cooling the tube furnace to room temperature, and taking a product out; and washing the product with a dilute hydrochloric acid solution, and vacuum-drying a washed product for 10 hours to obtain the molybdenum disulfide/graphene/carbon composite material with the hierarchical pore structure.

15. The use according to claim 9, wherein the molybdenum disulfide and the graphene both are uniformly dispersed as a monolayer structure in the composite nanofiber based on a carbon nanofiber.

16. The use according to claim 9, wherein the hierarchical pore structure has a pore diameter continuously distributed between 0.1 nm and 5 μm, and an average pore diameter of the hierarchical pore structure is 1.5 nm to 25 nm.

17. The use according to claim 9, wherein based on a pore volume, in the hierarchical pore structure, a microporous structure accounts for 25% to 60% and a mesoporous structure accounts for 40% to 75%.

18. The use according to claim 17, wherein the microporous structure is distributed on a surface of the composite nanofiber and a pore wall of the mesoporous structure.

19. The use according to claim 9, wherein the molybdenum disulfide/graphene/carbon composite material has a specific surface area of 500 m.sup.2/g to 3,200 m.sup.2/g.

20. The use according to claim 9, wherein the composite material is prepared by the following method: (1) adding 0.6 g to 1.5 g of polyacrylonitrile, 0.5 g to 1.2 g of polyvinylpyrrolidone, 0.2 g to 1.0 g of ammonium tetrathiomolybdate, and 0.05 g to 0.2 g of graphene to 10 g to 16 g of N,N-dimethylformamide, stirring a resulting solution for dissolution, and filtering the resulting solution through a 400-mesh stainless steel mesh to obtain a filtrate for later use; (2) taking an appropriate amount of the filtrate to conduct an electrostatic spinning to obtain a composite fiber film; (3) placing the composite fiber film in a tube furnace, and in a N2/H2 mixed atmosphere with a volume ratio of 9/1, heating the tube furnace to a temperature of 380° C. to 450° C. at a heating rate of 2° C./min to 6° C./min, holding the temperature for 1 hour to 6 hours, cooling the tube furnace to room temperature, and taking a treated composite fiber film out; (4) preparing a KOH saturated solution, subjecting the treated composite fiber film to an ultrasonic treatment in the KOH saturated solution for 1 hour and a static impregnation for 48 hours in the KOH saturated solution, and vacuum-drying an impregnated composite fiber film for 8 hours to obtain a dried composite fiber film, wherein a mass ratio of the treated composite fiber film to KOH is 1:(0.4-10); and (5) placing the dried composite fiber film in the tube furnace, and in an argon atmosphere, heating the tube furnace to 750° C. to 850° C. at a heating rate of 2° C./min to 10° C./min to conduct a high-temperature activation for 1 hour to 16 hours, cooling the tube furnace to room temperature, and taking a product out; and washing the product with a dilute hydrochloric acid solution, and vacuum-drying a washed product for 10 hours to obtain the molybdenum disulfide/graphene/carbon composite material with the hierarchical pore structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG. 1 is a schematic view of a structure of the molybdenum disulfide/graphene/carbon composite nanofiber with a hierarchical pore structure, where 1 represents a composite nanofiber, 2 represents a mesoporous structure, and 3 represents a microporous structure.

[0030] FIG. 2 is a schematic cross-sectional view of a structure of the molybdenum disulfide/graphene/carbon composite nanofiber with a hierarchical pore structure, where 1 represents a composite nanofiber, 2 represents a mesoporous structure, and 3 represents a microporous structure.

[0031] FIG. 3 is a scanning electron microscopy (SEM) image of the molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure prepared in Example 2.

[0032] FIG. 4 is an SEM image of a fiber cross-section in the molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure prepared in Example 2.

[0033] FIG. 5 is a transmission electron microscopy (TEM) image of the molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure prepared in Example 2.

DESCRIPTION OF THE EMBODIMENTS

[0034] 0.6 g of PAN, 0.5 g of PVP, 0.3 g of ATTM, and 0.05 g of graphene are added to 12 g of DMF, and a resulting mixture is stirred for dissolution and then filtered through a 400-mesh stainless steel mesh to obtain a filtrate for later use; an appropriate amount of the filtrate is taken to conduct electrostatic spinning at room temperature for 4 hours under the following parameters to obtain a composite fiber film: a spinning voltage of 20 kV, an advancing speed of 0.015 mL/min, a spinning receiving distance of 18 cm, and a syringe needle of 8 #; the composite fiber film is placed in a tube furnace, and in a N.sub.2/H.sub.2 (with a volume ratio of 9/1) mixed atmosphere, the composite fiber film is heated to 400° C. at a heating rate of 2° C./min, kept at the temperature for 4 hours, cooled to room temperature, and taken out; a KOH saturated solution is prepared, and the treated composite fiber film is subjected to ultrasonic treatment in the KOH saturated solution for 1 hour and static impregnation for 48 hours in the KOH saturated solution, and then vacuum-dried for 8 hours, where a mass ratio of the treated composite fiber film to KOH is 1:5; and the composite fiber film impregnated above is placed in a tube furnace, and in an argon atmosphere, the composite fiber film is heated to 750° C. at a heating rate of 2° C./min to undergo high-temperature activation for 2 hours, cooled to room temperature, taken out, washed with a dilute hydrochloric acid solution, and vacuum-dried for 10 hours to obtain a molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure. The product is composed of a composite nanofiber with a diameter of 80 nm to 300 nm; in mass percentage, the product includes 6% of molybdenum disulfide, 0.6% of graphene, and 93.4% of carbon; the product has an SSA of 600 m.sup.2/g, a pore diameter continuously distributed between 0.1 nm and 5 μm, and an average pore diameter of 1.6 nm; and in a pore structure of the product, a microporous structure accounts for 58% and a mesoporous structure accounts for 42%. The product can be used in LIB negative electrode materials, supercapacitor electrode materials, and catalytic materials for hydrogen production by water electrolysis.

EXAMPLES OF THE PRESENT DISCLOSURE

[0035] The embodiments of the present disclosure will be described in detail below with reference to examples. If no specific conditions are specified in the examples, conventional conditions or conditions recommended by a manufacturer will be adopted. All of the reagents or instruments used are conventional commercially available products.

Example 1

[0036] 0.6 g of PAN, 0.5 g of PVP, 0.3 g of ATTM, and 0.05 g of graphene were added to 12 g of DMF, and a resulting mixture is stirred for dissolution and then filtered through a 400-mesh stainless steel mesh to obtain a filtrate for later use; an appropriate amount of the filtrate was taken to conduct electrostatic spinning at room temperature for 4 hours under the following parameters to obtain a composite fiber film: a spinning voltage of 20 kV, an advancing speed of 0.015 mL/min, a spinning receiving distance of 18 cm, and a syringe needle of 8 #; the composite fiber film was placed in a tube furnace, and in a N.sub.2/H.sub.2 (with a volume ratio of 9/1) mixed atmosphere, the composite fiber film was heated to 400° C. at a heating rate of 2° C./min, kept at the temperature for 4 hours, cooled to room temperature, and taken out; a KOH saturated solution was prepared, and the treated composite fiber film was subjected to ultrasonic treatment in the KOH saturated solution for 1 hour and static impregnation for 48 hours in the KOH saturated solution, and then vacuum-dried for 8 hours, where a mass ratio of the treated composite fiber film to KOH is 1:5; and the composite fiber film impregnated above was placed in a tube furnace, and in an argon atmosphere, the composite fiber film was heated to 750° C. at a heating rate of 2° C./min to undergo high-temperature activation for 2 hours, cooled to room temperature, taken out, washed with a dilute hydrochloric acid solution, and vacuum-dried for 10 hours to obtain a molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure. The product is composed of a composite nanofiber with a diameter of 80 nm to 300 nm; in mass percentage, the product includes 6% of molybdenum disulfide, 0.6% of graphene, and 93.4% of carbon; the product has an SSA of 600 m.sup.2/g, a pore diameter continuously distributed between 0.1 nm and 5 μm, and an average pore diameter of 1.6 nm; and in a pore structure of the product, a microporous structure accounts for 58% and a mesoporous structure accounts for 42%. The product can be used in LIB negative electrode materials, supercapacitor electrode materials, and catalytic materials for hydrogen production by water electrolysis.

Example 2

[0037] 1.5 g of PAN, 1.0 g of PVP, 0.8 g of ATTM, and 0.2 g of graphene were added to 16 g of DMF, and a resulting mixture was stirred for dissolution and then filtered through a 400-mesh stainless steel mesh to obtain a filtrate for later use; an appropriate amount of the filtrate was taken to conduct electrostatic spinning at room temperature for 2 hours under the following parameters to obtain a composite fiber film: a spinning voltage of 20 kV, an advancing speed of 0.015 mL/min, a spinning receiving distance of 18 cm, and a syringe needle of 8 #; the composite fiber film was placed in a tube furnace, and in a N.sub.2/H.sub.2 (with a volume ratio of 9/1) mixed atmosphere, the composite fiber film was heated to 450° C. at a heating rate of 6° C./min, kept at the temperature for 1 hour, cooled to room temperature, and taken out; a KOH saturated solution was prepared, and the treated composite fiber film was subjected to ultrasonic treatment in the KOH saturated solution for 1 hour and static impregnation for 48 hours in the KOH saturated solution, and then vacuum-dried for 8 hours, where a mass ratio of the treated composite fiber film to KOH was 1:0.5; and the composite fiber film impregnated above was placed in a tube furnace, and in an argon atmosphere, the composite fiber film was heated to 850° C. at a heating rate of 8° C./min to undergo high-temperature activation for 15 hours, cooled to room temperature, taken out, washed with a dilute hydrochloric acid solution, and vacuum-dried for 10 hours to obtain a molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure. The product is composed of a composite nanofiber with a diameter of 60 nm to 420 nm; in mass percentage, the product includes 33% of molybdenum disulfide, 7% of graphene, and 60% of carbon; the product has an SSA of 2522 m.sup.2/g, a pore diameter continuously distributed between 0.1 nm and 5 μm, and an average pore diameter of 12.6 nm; and in a pore structure of the product, a microporous structure accounts for 37% and a mesoporous structure accounts for 63%. The product can be used in mercury adsorption materials.

[0038] FIG. 3 and FIG. 4 are SEM images of the molybdenum disulfide/graphene/carbon composite material prepared in this example, and it can be seen that mesoporous structures with different sizes are distributed in an axial direction in the fiber, and a large number of microporous structures are distributed on a surface of the fiber and a pore wall of the mesoporous structure. FIG. 5 is a TEM image of the molybdenum disulfide/graphene/carbon composite material prepared in this example, and it can be seen that molybdenum disulfide and graphene are highly uniformly dispersed as a monolayer structure in the composite fiber.

Example 3

[0039] 1.0 g of PAN, 1.2 g of PVP, 1.0 g of ATTM, and 0.1 g of graphene were added to 10 g of DMF, and a resulting mixture was stirred for dissolution and then filtered through a 400-mesh stainless steel mesh to obtain a filtrate for later use; an appropriate amount of the filtrate was taken to conduct electrostatic spinning at room temperature for 10 hours under the following parameters to obtain a composite fiber film: a spinning voltage of 20 kV, an advancing speed of 0.015 mL/min, a spinning receiving distance of 18 cm, and a syringe needle of 8 #; the composite fiber film was placed in a tube furnace, and in a N.sub.2/H.sub.2 (with a volume ratio of 9/1) mixed atmosphere, the composite fiber film was heated to 380° C. at a heating rate of 4° C./min, kept at the temperature for 6 hours, cooled to room temperature, and taken out; a KOH saturated solution was prepared, and the treated composite fiber film was subjected to ultrasonic treatment in the KOH saturated solution for 1 hour and static impregnation for 48 hours in the KOH saturated solution, and then vacuum-dried for 8 hours, where a mass ratio of the treated composite fiber film to KOH was 1:10; and the composite fiber film impregnated above was placed in a tube furnace, and in an argon atmosphere, the composite fiber film was heated to 800° C. at a heating rate of 10° C./min to undergo high-temperature activation for 1 hour, cooled to room temperature, taken out, washed with a dilute hydrochloric acid solution, and vacuum-dried for 10 hours to obtain a molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure. The product is composed of a composite nanofiber with a diameter of 150 nm to 500 nm; in mass percentage, the product includes 14% of molybdenum disulfide, 6.2% of graphene, and 79.8% of carbon; the product has an SSA of 3152 m.sup.2/g, a pore diameter continuously distributed between 0.1 nm and 5 μm, and an average pore diameter of 23.6 nm; and in a pore structure of the product, a microporous structure accounts for 25.8% and a mesoporous structure accounts for 74.2%. The product can be used in mercury adsorption materials.

Example 4

[0040] 1.3 g of PAN, 0.6 g of PVP, 0.4 g of ATTM, and 0.15 g of graphene were added to 10 g of DMF, and a resulting mixture was stirred for dissolution and then filtered through a 400-mesh stainless steel mesh to obtain a filtrate for later use; an appropriate amount of the filtrate was taken to conduct electrostatic spinning at room temperature for 8 hours under the following parameters to obtain a composite fiber film: a spinning voltage of 20 kV, an advancing speed of 0.015 mL/min, a spinning receiving distance of 18 cm, and a syringe needle of 8 #; the composite fiber film was placed in a tube furnace, and in a N.sub.2/H.sub.2 (with a volume ratio of 9/1) mixed atmosphere, the composite fiber film was heated to 425° C. at a heating rate of 3° C./min, kept at the temperature for 5 hours, cooled to room temperature, and taken out; a KOH saturated solution was prepared, and the treated composite fiber film was subjected to ultrasonic treatment in the KOH saturated solution for 1 hour and static impregnation for 48 hours in the KOH saturated solution, and then vacuum-dried for 8 hours, where a mass ratio of the treated composite fiber film to KOH was 1:6; and the composite fiber film impregnated above was placed in a tube furnace, and in an argon atmosphere, the composite fiber film was heated to 820° C. at a heating rate of 6° C./min to undergo high-temperature activation for 12 hours, cooled to room temperature, taken out, washed with a dilute hydrochloric acid solution, and vacuum-dried for 10 hours to obtain a molybdenum disulfide/graphene/carbon composite material with a hierarchical pore structure. The product is composed of a composite nanofiber with a diameter of 60 nm to 500 nm; in mass percentage, the product includes 9.5% of molybdenum disulfide, 1.9% of graphene, and 88.6% of carbon; the product has an SSA of 1855 m.sup.2/g, a pore diameter continuously distributed between 0.1 nm and 5 μm, and an average pore diameter of 4.5 nm; and in a pore structure of the product, a microporous structure accounts for 43% and a mesoporous structure accounts for 57%. The product can be used in LIB negative electrode materials, supercapacitor electrode materials, and catalytic materials for hydrogen production by water electrolysis.

INDUSTRIAL APPLICABILITY

[0041] The molybdenum disulfide/graphene/carbon composite material prepared by the present disclosure can be widely used in fields such as LIB negative electrode materials, supercapacitor electrode materials, catalytic materials for hydrogen production by water electrolysis, and mercury adsorption materials. The molybdenum disulfide/graphene/carbon composite material where a microporous structure accounts for more than 40% in the hierarchical pore structure is conducive to the transport of small-volume ions such as lithium ions, potassium ions, and hydrogen ions, and is suitable for LIB negative electrode materials, supercapacitor electrode materials, and catalytic materials for hydrogen production by water electrolysis. The molybdenum disulfide/graphene/carbon composite material where a microporous structure accounts for less than 40% in the hierarchical pore structure is suitable for mercury adsorption materials, because a large number of mesoporous structures are conducive to the diffusion of mercury ions.