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CN-121983535-A - Preparation method of biological carbon-zinc sulfide-tungsten sulfide heterojunction composite material and heterojunction composite material

CN121983535ACN 121983535 ACN121983535 ACN 121983535ACN-121983535-A

Abstract

The invention discloses a preparation method of a biochar-zinc sulfide-tungsten sulfide heterojunction composite material, which comprises the following steps of S1, dissolving sodium tungstate, hydroxylamine hydrochloride, sodium hydroxide, thiourea and zinc chloride in deionized water, uniformly stirring to obtain a yellowish transparent reaction liquid, S2, preparing biochar, mixing the reaction liquid with the biochar in a reaction kettle, performing hydrothermal reaction for 8-48 hours at a constant temperature, wherein the constant temperature is any temperature with a temperature value within a range of 180-240 ℃, S3, filtering, cleaning and drying the product obtained in the step S2 to obtain a heterojunction composite material precursor, and S4, calcining the heterojunction composite material precursor in an inert gas atmosphere to obtain the biochar-zinc sulfide-tungsten sulfide heterojunction composite material, wherein the calcining temperature is 850-950 ℃.

Inventors

  • WANG YAOHUI
  • XIA YANGFENG
  • ZHENG ZHE
  • SUN YANLI
  • ZHOU YOUJIE
  • CHEN JINMAO
  • HUANG LONG
  • WANG XUDONG
  • XU WANLI
  • SU XING
  • AN GAOJUN
  • XU XIMENG

Assignees

  • 军事科学院系统工程研究院军事新能源技术研究所

Dates

Publication Date
20260505
Application Date
20251226

Claims (10)

  1. 1. The preparation method of the biochar-zinc sulfide-tungsten sulfide heterojunction composite material is characterized by comprising the following steps of: s1, dissolving sodium tungstate, hydroxylamine hydrochloride, sodium hydroxide, thiourea and zinc chloride in deionized water and uniformly stirring to obtain a yellowish transparent reaction solution; S2, preparing biochar, mixing the reaction liquid with the biochar in a reaction kettle, and performing hydrothermal reaction for 8-48 hours at a constant temperature, wherein the constant temperature is any temperature with a temperature value within a range of 180-240 ℃; S3, filtering, cleaning and drying the product obtained in the step S2 to obtain a heterojunction composite material precursor; and S4, calcining the heterojunction composite material precursor in an inert gas atmosphere to obtain the biochar-zinc sulfide-tungsten sulfide heterojunction composite material, wherein the calcining temperature is 850-950 ℃.
  2. 2. The method for preparing the biochar-zinc sulfide-tungsten sulfide heterojunction composite material according to claim 1, wherein in the reaction solution in the step S1, the concentration of sodium tungstate is 0.05-0.2 mol/L, the concentration of zinc chloride is 0.0005-0.1 mol/L, the concentration of hydroxylamine hydrochloride is 0.1-0.6 mol/L, the concentration of sodium hydroxide is 0.01-0.2 mol/L, and the concentration of thiourea is 0.1-0.9 mol/L.
  3. 3. The method for preparing the biochar-zinc sulfide-tungsten sulfide heterojunction composite material according to claim 1, wherein the hydrothermal reaction in the step S2 is performed under the pressure of 1.5-3.5 MPa, and the deviation between the constant temperature and the set temperature is not more than +/-0.5 ℃.
  4. 4. The preparation method of the biochar-zinc sulfide-tungsten sulfide heterojunction composite material according to any one of claims 1-3 further comprises the step of repeating the reaction step after the step S3, wherein the step of repeating the reaction step is carried out for 1-5 times after mixing the heterojunction composite material precursor with the newly prepared reaction liquid in the step S1 for reaction and then washing and drying the reaction liquid.
  5. 5. The method for preparing the biochar-zinc sulfide-tungsten sulfide heterojunction composite material according to claim 1, wherein the biochar density is 0.05-0.15 g +. Is prepared by carbonizing bassal wood at 850-950 ℃.
  6. 6. A biochar-zinc sulfide-tungsten sulfide heterojunction composite material characterized by being prepared by the method for preparing the biochar-zinc sulfide-tungsten sulfide heterojunction composite material according to any one of claims 1-5.
  7. 7. The biochar-zinc sulfide-tungsten sulfide heterojunction composite material according to claim 6, wherein zinc sulfide and tungsten sulfide in the composite material are two-dimensional nano-sheets with the diameter of 100-300 nm, the tungsten sulfide nano-sheets grow by taking zinc sulfide as a nucleation active point, and the two nano-sheets are anchored on the surface of the biochar with a honeycomb three-dimensional structure.
  8. 8. The biochar-zinc sulfide-tungsten sulfide heterojunction composite material of claim 6 or 7, wherein the tungsten sulfide accounts for 10% -80% by mass, and the zinc sulfide accounts for 0.2% -0.5% by mass.
  9. 9. A negative electrode for a lithium ion battery, characterized by comprising the biochar-zinc sulfide-tungsten sulfide heterojunction composite material as defined in any one of claims 6 to 8.
  10. 10. A negative electrode for a sodium ion battery, characterized by comprising the biochar-zinc sulfide-tungsten sulfide heterojunction composite material as defined in any one of claims 6 to 8.

Description

Preparation method of biological carbon-zinc sulfide-tungsten sulfide heterojunction composite material and heterojunction composite material Technical Field The invention relates to the technical field of new energy battery materials, in particular to a preparation method of a biological carbon-zinc sulfide-tungsten sulfide heterojunction composite material. Background Lithium is used as a negative electrode material of lithium ion batteries, sodium ion batteries and the like, and transition metal sulfides have better conductivity and good diffusion kinetics for lithium ions, sodium ions and the like because bond energy is weaker than that of transition metal oxides, and in addition, have higher theoretical capacity. In addition, the interlayer spacing of the layered transition metal sulfide is favorable for rapid diffusion, intercalation and deintercalation of lithium ions, sodium ions and the like due to low potential barriers for ion migration and intercalation reaction, so that the layered transition metal sulfide has great potential in the fields of lithium storage and sodium storage. In the prior art, in order to improve the conductivity of the transition metal sulfide, a composite material in which the transition metal sulfide is inserted into the surface of the carbon microsphere serving as a supporting framework is disclosed in patent application CN110690419a, but the obtained composite material still needs to be improved in the aspects of conductivity, rate performance, charge-discharge cycle and the like. In addition, for the preparation of transition metal sulfides, there are methods such as hydrothermal synthesis and chemical vapor deposition, but these preparation methods still have problems of low efficiency and improved properties of the obtained composite materials. Disclosure of Invention The invention provides a preparation method of a biological carbon-zinc sulfide-tungsten sulfide heterojunction composite material and application of a preparation thereof, which are used for solving the core technical problems that tungsten sulfide is difficult to form a nucleus, and a heterojunction with uniform structure and good structure is difficult to form with a carbon substrate in the prior art. The invention is characterized in that trace zinc sulfide ZnS is introduced as tungsten sulfideThe nucleation active points of the two sulfides are uniformly and tightly compounded on the biological carbon substrate through a stepwise nucleation-epitaxial growth mechanism. Specifically, the invention provides a preparation method of a biochar-zinc sulfide-tungsten sulfide heterojunction composite material, which comprises the following steps: s1, dissolving sodium tungstate, hydroxylamine hydrochloride, sodium hydroxide, thiourea and zinc chloride in deionized water and uniformly stirring to obtain a yellowish transparent reaction solution; S2, preparing biochar, mixing the reaction liquid with the biochar in a reaction kettle, and performing hydrothermal reaction for 8-48 hours at a constant temperature, wherein the constant temperature is any temperature with a temperature value within a range of 180-240 ℃; S3, filtering, cleaning and drying the product obtained in the step S2 to obtain a heterojunction composite material precursor; and S4, calcining the heterojunction composite material precursor in an inert gas atmosphere to obtain the biochar-zinc sulfide-tungsten sulfide heterojunction composite material, wherein the calcining temperature is 850-950 ℃. Further, in the reaction solution in the step S1, the concentration of sodium tungstate is 0.05-0.2 mol/L, the concentration of zinc chloride is 0.0005-0.1 mol/L, the concentration of hydroxylamine hydrochloride is 0.1-0.6 mol/L, the concentration of sodium hydroxide is 0.01-0.2 mol/L, and the concentration of thiourea is 0.1-0.9 mol/L. Further, the hydrothermal reaction in the step S2 is performed under the pressure of 1.5-3.5 MPa, and the deviation between the constant temperature and the set temperature is not more than +/-0.5 ℃. Further, the step S3 is followed by a repeated reaction step, wherein the heterojunction composite material precursor and the newly prepared reaction liquid in the step S1 are mixed for reaction, and then are washed and dried, and the repeated reaction step is carried out for 1-5 times. Further, the biochar density is 0.05-0.15 g +.Is prepared by carbonizing bassal wood at 850-950 ℃. The invention also provides a biochar-zinc sulfide-tungsten sulfide heterojunction composite material, which is prepared by the preparation method of the biochar-zinc sulfide-tungsten sulfide heterojunction composite material. Further, in the composite material, zinc sulfide and tungsten sulfide are two-dimensional nano sheets with the diameter of 100-300 nm, the tungsten sulfide nano sheets grow by taking zinc sulfide as a nucleation active point, and the two nano sheets are anchored on the surface of biological carbon with a honeycomb three