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CN-122010183-A - Preparation method and application of sea urchin-shaped lignin carbon mesophase derived high-energy-density cathode material

CN122010183ACN 122010183 ACN122010183 ACN 122010183ACN-122010183-A

Abstract

The invention discloses a preparation method and application of a sea urchin-shaped lignin carbon mesophase derived high-energy-density anode material, and belongs to the field of biomass nano materials. According to the invention, the industrial by-product lignin is taken as a carbon source, and the high-energy-density anode material derived from the sea urchin-shaped lignin carbon mesophase is successfully constructed through metal salt coordination-guided self-assembly, in-situ doping and segmented carbonization strategies, so that the accurate conversion of lignin from unordered macromolecules to ordered multifunctional nano materials is realized. The high-energy-density positive electrode material prepared by the method is used for the zinc ion super capacitor, shows high specific capacitance, excellent multiplying power performance and ultra-long cycle life, realizes effective conversion from biomass waste to energy materials, and provides a new technical scheme for application of lignin in the energy field.

Inventors

  • XU JIKUN
  • YANG JUNBO
  • GUO JUN
  • ZHOU PENGFEI

Assignees

  • 武汉科技大学

Dates

Publication Date
20260512
Application Date
20260209

Claims (10)

  1. 1. The preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy-density cathode material is characterized by comprising the following steps of: (1) Adding lignin, ferric nitrate and zinc sulfate into water, uniformly stirring, standing for ageing, and filtering to obtain filter residues, namely Fe coordinated lignin; (2) Dispersing the filter residue obtained in the step (1), urea and ammonium chloride into solvent water, uniformly stirring, and freeze-drying to obtain brown powder; (3) Continuously performing two-section sectional calcination on the brown powder in a tube furnace under the protection of nitrogen to obtain a Fe coordinated carbon nanomaterial precursor; (4) Fully mixing and grinding the Fe coordinated carbon material precursor obtained in the step (3) and potassium bicarbonate, calcining in a tube furnace under the protection of nitrogen, and when the obtained black product is washed to be neutral, carrying out suction filtration by adopting a water-based filter membrane and drying to obtain an Fe coordinated sea urchin-shaped lignin carbon intermediate phase; (5) Dispersing the Fe coordinated sea urchin-shaped lignin carbon intermediate phase obtained in the step (4) into solvent water together with manganese sulfate, potassium permanganate and calcium chloride, uniformly stirring, then carrying out a hydrothermal reaction, filtering a reaction system after the hydrothermal reaction is finished, washing the obtained filter residue with water, and drying to obtain the sea urchin-shaped lignin carbon intermediate phase derived high-energy-density anode material.
  2. 2. The preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy-density anode material is characterized in that in the step (1), the ratio of lignin mass to water volume is 1g (10-40) mL, and the adding concentration range of ferric nitrate and zinc sulfate in water is 15-45 mmol/L.
  3. 3. The preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy-density positive electrode material is characterized in that in the step (1), the time for standing and aging after stirring is 8-20 hours, and an aqueous filter membrane is adopted for filtering, wherein the pore diameter is 0.22-0.65 mu m.
  4. 4. The preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy-density anode material is characterized in that in the step (2), the mass ratio of filter residues to urea to ammonium chloride is 1 (4-6): 2-4, the freeze drying temperature is-60 to-50 ℃, and the drying time is 12-48 h.
  5. 5. The preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy-density anode material is characterized in that in the step (3), the first-stage calcination temperature in continuous two-stage segmented calcination is 500-600 ℃, the heat preservation time is 0.5-1.5 h, the second-stage calcination temperature is 750-850 ℃, and the heat preservation time is 0.5-1.5 h.
  6. 6. The preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy density cathode material is characterized in that in the step (4), the mass ratio of the Fe coordinated carbon nanomaterial precursor to the potassium bicarbonate is 1 (2-4), the temperature is raised to 750-850 ℃ at the temperature rise rate of 3-8 ℃ per minute, the heat preservation time is 0.5-1.5 h, the concentration of hydrochloric acid used for washing is 0.5-2 mol/L, and the pore diameter of an aqueous filter membrane is 0.20-0.65 mu m.
  7. 7. The preparation method of the sea urchin-shaped lignin carbon intermediate phase derived high-energy density anode material is characterized in that in the step (5), the concentration range of Fe coordinated sea urchin-shaped lignin carbon intermediate phase dispersed in solvent water is 1-3 g/L, the concentration range of manganese sulfate in solvent water is 3-6 mmol/L, and the molar ratio of manganese sulfate, calcium chloride and potassium permanganate is 1 (1.5-2.5): 4-7.
  8. 8. The preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy-density anode material according to claim 1, wherein the temperature of the hydrothermal reaction is 130-150 ℃ and the reaction time is 8-12 h.
  9. 9. The sea urchin-like lignin carbon mesophase derived high energy density cathode material prepared by the method of any one of claims 1-8.
  10. 10. The application of the sea urchin-shaped lignin carbon mesophase derived high-energy-density positive electrode material in the zinc ion supercapacitor, which is characterized in that the high-energy-density positive electrode material is uniformly mixed with a conductive agent and a binder by using a solvent, and then uniformly coated on the surface of a metal substrate to serve as a positive electrode, a zinc sheet serves as a negative electrode, and a mixed solution of zinc sulfate and manganese sulfate serves as an electrolyte, so that the zinc ion supercapacitor is assembled.

Description

Preparation method and application of sea urchin-shaped lignin carbon mesophase derived high-energy-density cathode material Technical Field The invention belongs to the field of biomass materials, and relates to a preparation method and application of a sea urchin-shaped lignin carbon mesophase derived high-energy-density anode material. Background Lignin is the second largest natural organic high molecular polymer with reserves next to cellulose in nature, widely existing in the cell walls of woody and herbaceous plants, and forms the main component of plant skeletons together with cellulose and hemicellulose. Most of the lignin in industry is currently burned directly to supply energy as a by-product of pulp and paper making and biorefinery industry, and only a very small part is utilized with high value. In recent years, carbon nano materials are paid attention to in various fields, lignin is high in carbon content, wide in source, renewable and low in cost, and a large number of active groups such as phenolic hydroxyl groups, carboxyl groups and methoxy groups are also contained in a molecular structure, so that the prepared lignin carbon nano material has the high specific surface area of the carbon nano material, excellent conductivity and structural adjustability of lignin derivative materials, and has wide application prospects in the fields of electrodes, adsorption, catalysis and the like. The method for preparing the lignin carbon nano material is various and comprises a direct pyrolysis carbonization method, a pretreatment modification, carbonization activation, a template method and the like, but has a plurality of defects. The method for preparing the lignin carbon nano material by direct pyrolysis carbonization has the advantages of small specific surface area, disordered pore structure, limited active site and poor electrochemical performance, is difficult to meet actual demands, can regulate and control the structure and the performance of the material by pretreatment modification such as oxidization, sulfonation and the like, but has the problems of large usage of an activating agent, complicated washing separation, low carbon yield caused by easy excessive degradation of lignin and high cost, and can regulate and control the size and pore canal distribution of the material by a template method, but has complex template preparation and removal operation, severe experimental conditions, expensive and difficult recovery of part of templates, not only increases the process complexity and the energy consumption, is easy to influence the performance stability due to template residues, but also can cause potential environmental pollution, is unfavorable for green large-scale production, and severely limits the popularization and the application of the lignin carbon nano material. Disclosure of Invention The invention aims to solve the technical problem of providing a preparation method of a sea urchin-shaped lignin carbon mesophase derived high-energy density anode material aiming at the defects of the prior art, and the accurate construction from disordered biomass lignin to the high-performance anode material is realized through a multi-step cooperative process of coordination guiding, in-situ doping, segmented carbonization, secondary activation and the like. The invention adopts the technical proposal for solving the problems that: the preparation method of the sea urchin-shaped lignin carbon mesophase derived high-energy-density positive electrode material comprises the following steps of: (1) Adding lignin, ferric nitrate and zinc sulfate into water, uniformly stirring, standing for ageing, and filtering to obtain filter residues, namely Fe coordinated lignin; (2) Dispersing the filter residue obtained in the step (1), urea and ammonium chloride into solvent water, uniformly stirring, and freeze-drying to obtain Fe coordinated lignin precursor (brown powder); (3) Continuously and sectionally calcining the brown powder obtained in the step (2) in a two-section manner in a tube furnace under the protection of nitrogen to obtain a Fe coordinated carbon nanomaterial precursor (black product A); (4) Fully mixing and grinding the black product A obtained in the step (3) with potassium bicarbonate, calcining in a tube furnace under the protection of nitrogen to obtain a black product B, and repeatedly washing with hydrochloric acid to obtain a Fe coordinated sea urchin-shaped lignin carbon intermediate phase (Fe-N-C); (5) Dispersing the Fe coordinated sea urchin-shaped lignin carbon intermediate phase obtained in the step (4) into solvent water together with manganese sulfate, potassium permanganate and calcium chloride, uniformly stirring, then carrying out a hydrothermal reaction, filtering a reaction system after the hydrothermal reaction is finished, washing the obtained filter residue with water, and drying to obtain the sea urchin-shaped lignin carbon intermediate phase derived high-energy