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CN-116598495-B - Metal oxide/mesoporous manganese dioxide/conductive polymer composite material and preparation method and application thereof

CN116598495BCN 116598495 BCN116598495 BCN 116598495BCN-116598495-B

Abstract

The invention belongs to the technical field of lithium battery materials, and particularly relates to a metal oxide/mesoporous manganese dioxide/conductive polymer composite material, and a preparation method and application thereof. The preparation method comprises the following steps of 1) ball-milling and crushing commercial metal oxide, 2) mixing metal oxide powder with an organic polymer monomer and methyl orange solution, and performing ultrasonic dispersion to obtain a mixed solution, 3) adding a potassium permanganate solution into the mixed solution, performing high-pressure hydrothermal reaction under a stirring state to obtain a composite material, and 4) performing alkali treatment on the composite material, and performing suction filtration, washing and drying to obtain the metal oxide/mesoporous manganese dioxide/conductive polymer composite material. The metal oxide/mesoporous manganese dioxide/conductive polymer composite material can be simply, efficiently and cost-effectively prepared into the lithium battery positive electrode material with high specific capacity, high conductivity and high stability, is easy to industrialize, and solves the problems of low conductivity and poor rate discharge performance of the traditional metal oxide positive electrode material.

Inventors

  • SHI XUE
  • MENG QINGFEI
  • Qi Yuyang
  • ZHOU ZHOU

Assignees

  • 武汉中原长江科技发展有限公司

Dates

Publication Date
20260505
Application Date
20230412

Claims (10)

  1. 1. The metal oxide/mesoporous manganese dioxide/conductive polymer composite material is characterized by comprising metal oxide particles, mesoporous manganese dioxide loaded on the surfaces of the metal oxide particles and a conductive polymer, wherein the conductive polymer has the following structural general formula: The polymer monomer is 3, 4-thiophene lithium dicarboxylic acid, the polymerization site between the monomer and the monomer is 1,2 sites on a thiophene ring, R1 is an alkane chain contained in a lithium carboxylate group on the thiophene ring, and the carbon number of R1 is 2-10.
  2. 2. The metal oxide/mesoporous manganese dioxide/conductive polymer composite material according to claim 1, wherein the mass ratio of the metal oxide to the mesoporous manganese dioxide to the conductive polymer is 1 (0.01-0.1).
  3. 3. The metal oxide/mesoporous manganese dioxide/conductive polymer composite according to claim 1 or 2, wherein the metal oxide is one or more of chromium oxide, vanadium oxide, and lead oxide.
  4. 4. The method for preparing the metal oxide/mesoporous manganese dioxide/conductive polymer composite material according to claim 1, which is characterized by mainly comprising the following steps: 1) Mixing metal oxide powder with methyl orange solution and 3, 4-thiophene dicarboxylic acid monomer, and performing dispersion treatment by using ultrasonic to obtain a mixed solution; 2) Transferring the mixed solution obtained in the step 1) into a hydrothermal kettle, adding a potassium permanganate solution under stirring, and sealing for hydrothermal reaction; 3) Washing the solid product obtained by the hydrothermal reaction in the step 2) with water, filtering, adding a lithium hydroxide solution, performing alkali treatment under the condition of heating and stirring, washing and drying to obtain the finished metal oxide/mesoporous manganese dioxide/conductive polymer composite material.
  5. 5. The method of producing a metal oxide/mesoporous manganese dioxide/conductive polymer composite according to claim 4, wherein the metal oxide powder is obtained by pulverizing commercial metal oxide and has a particle size of not more than 30. Mu.m.
  6. 6. The method for preparing a metal oxide/mesoporous manganese dioxide/conductive polymer composite according to claim 4, wherein in the step 1), methyl orange is added as a conductive polymer template agent, the concentration of the solution is 2-10 mg/ml, and the mass ratio of the metal oxide to the 3, 4-thiophene dicarboxylic acid is 1 (0.01-0.1).
  7. 7. The method of claim 4, wherein in the step 2), the concentration of the metal oxide and the 3, 4-thiophene dicarboxylic acid monomer in the mixed solution after the potassium permanganate solution is added is 10-100 mg/ml and 1-10 mg/ml, respectively.
  8. 8. The method of producing a metal oxide/mesoporous manganese dioxide/conductive polymer composite according to claim 4, wherein in step 2), potassium permanganate is added as an oxidant and a source of manganese oxide in an amount such that the mass ratio of manganese dioxide to metal oxide corresponding to the potassium permanganate solution is 1 (0.01 to 0.1), and the concentration of the potassium permanganate solution used is 1 to 8mg/ml.
  9. 9. The method for preparing the metal oxide/mesoporous manganese dioxide/conductive polymer composite material according to claim 4, wherein in the step 2), the temperature of the hydrothermal reaction is 100-200 ℃, the hydrothermal reaction time is 1-5 h, in the step 3), after washing and suction filtration, the metal oxide/mesoporous manganese dioxide/conductive polymer composite material is ultrasonically dispersed and mixed with a lithium hydroxide solution in a wet state, so that lithium hydroxide can be rapidly and comprehensively reacted with a solid product obtained by the hydrothermal reaction, and the concentration of the lithium hydroxide solution is 1-5 mol/L.
  10. 10. A lithium metal oxide battery, characterized in that the positive electrode material is the metal oxide/mesoporous manganese dioxide/conductive polymer composite material according to claim 1.

Description

Metal oxide/mesoporous manganese dioxide/conductive polymer composite material and preparation method and application thereof Technical Field The invention belongs to the technical field of lithium battery materials, and particularly relates to a metal oxide/mesoporous manganese dioxide/conductive polymer composite material, and a preparation method and application thereof. Background In the selection of the lithium primary battery anode material, the chromium oxide (Cr 8O21) has the advantages of high theoretical energy density (1210 Wh/kg), high discharge voltage platform (> 3.0V), good medium-low rate discharge performance and the like. However, the pure chromium oxide material has poor conductivity, so that the high-rate discharge capacity of the pure chromium oxide material is low, and the discharge specific capacity and the theoretical value have larger difference. Therefore, the improvement of the chromium oxide material, the improvement of the conductivity and the rate discharge performance of the material, is an important direction for the improvement of the lithium primary battery. Conventional metal oxide modification means are mostly mechanical mixing or simple cladding methods. CN112968176A mechanically mixes chromium oxide (Cr 8O21) with a carbon nano tube by using a ball milling method and prepares a composite oxide material, so that the discharge capacity and the conductivity of the material are improved, but the simple ball milling treatment easily causes the defects of uneven mixing and unstable discharge effect of the material. CN102339994A combines chromium oxide and graphene in a hydrothermal coprecipitation mode, so that the conductivity of the composite material is effectively improved, and the cycle performance is also greatly improved. However, chromium oxide is extremely sensitive to solvents, especially in high-temperature and high-pressure environments, chromic anhydride (H 2CrO4) is extremely easy to generate, and the preparation of the chromium oxide/graphene composite material by adopting a hydrothermal coprecipitation method is very difficult. The current research on metal oxide improvement is mainly focused on improving the conductivity of chromium oxide, but most of improvement means have the problems of uneven doping of composite materials, harsh preparation conditions, low yield and the like, and limit the further application of the improved composite materials. Disclosure of Invention The invention aims to provide a metal oxide/mesoporous manganese dioxide/conductive polymer composite material aiming at the defects of the prior art, and can solve the problems of low conductivity and low high-rate discharge performance of a battery of the traditional metal oxide cathode material. The technical scheme adopted by the invention for achieving the purpose is as follows: A metal oxide/mesoporous manganese dioxide/conductive polymer composite material comprises metal oxide particles, mesoporous manganese dioxide loaded on the surfaces of the metal oxide particles and a conductive polymer, wherein the structural general formula of the conductive polymer is shown in the following formula 1: 1 (1) In the formula 1, the polymer monomer is 3, 4-thiophene lithium dicarboxylic acid, the polymerization site between the monomer and the monomer is 1,2 sites on a thiophene ring, R1 is an alkane chain contained in a lithium carboxylate group on the thiophene ring, and the carbon number of R1 is 2-10. According to the above scheme, the above conductive polymer is obtained by introducing Li ions into the thiophene polymer shown in formula 2 by alkali treatment (i.e., reaction of the thiophene polymer with lithium hydroxide), so that carboxyl groups on the thiophene polymer are converted into lithium carboxylate groups. 2, 2 In the formula 2, the polymer monomer is 3, 4-thiophene dicarboxylic acid, the polymerization site between the monomer and the monomer is a1, 2 site on a thiophene ring, wherein R1 is an alkane chain contained in a carboxylic acid group on the thiophene ring, wherein the carbon number of R1 is 2-10, and n is the degree of polymerization. According to the scheme, the mass ratio of the metal oxide to the mesoporous manganese dioxide to the conductive polymer is 1 (0.01-0.1). According to the scheme, the metal oxide is one or more of chromium oxide, vanadium oxide, lead oxide and the like. The invention also provides a preparation method of the metal oxide/mesoporous manganese dioxide/conductive polymer composite material, which mainly comprises the following steps: 1) Mixing metal oxide powder with methyl orange solution and 3, 4-thiophene dicarboxylic acid monomer, and performing dispersion treatment by using ultrasonic to obtain a mixed solution; 2) Transferring the mixed solution obtained in the step 1) into a hydrothermal kettle, adding a potassium permanganate solution under stirring, and sealing for hydrothermal reaction; 3) Washing the solid product obtained by the hy