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KR-20260063799-A - MODIFY METHOD OF SURFACE OF CARBON MATERIAL FOR SUPERCAPACITOR AND CARBON MATERIAL FOR SUPERCAPACITOR SURFACE MODIFIED USING THE SAME

KR20260063799AKR 20260063799 AKR20260063799 AKR 20260063799AKR-20260063799-A

Abstract

The present embodiments relate to a method for surface modification of a carbon material for a supercapacitor and a carbon material for a supercapacitor surface modified using the same. A method for surface modification of a carbon material for a supercapacitor according to one embodiment may include: a step of preparing a carbon raw material; a step of performing a first heat treatment of the carbon raw material in an atmospheric atmosphere; a step of first cooling the carbon raw material that has undergone the first heat treatment; a step of performing a second heat treatment of the carbon raw material that has undergone the first cooling in a nitrogen-containing gas atmosphere; and a step of second cooling the carbon raw material that has undergone the second heat treatment to obtain a surface modified carbon material.

Inventors

  • 권다혜

Assignees

  • (주)포스코퓨처엠

Dates

Publication Date
20260507
Application Date
20241031

Claims (20)

  1. Step of preparing carbon raw materials; A step of performing a first heat treatment on the above carbon raw material in an atmospheric environment; A step of first cooling the above-mentioned first heat-treated carbon raw material; A step of heat-treating the first cooled carbon raw material in a second heat treatment in a nitrogen-containing gas atmosphere; and A step of obtaining a surface-modified carbon material by cooling the above second heat-treated carbon raw material a second time; A method for surface modification of a carbon material for a supercapacitor, comprising
  2. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein, in the step of preparing the carbon raw material, the specific surface area of the carbon raw material is in the range of 1,500 m² /g to 1,800 m² /g.
  3. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein the first heat treatment is performed at 400 to 600°C for 0.5 to 2 hours.
  4. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, comprising a first purging step for 0.5 to 12 hours in an atmospheric environment after the step of preparing the carbon raw material.
  5. In paragraph 4, A method for surface modification of a carbon material for a supercapacitor, wherein the first purging step controls the air flow at a volumetric flow rate of 50 to 2,000 mL/min.
  6. In paragraph 5, A method for surface modification of a carbon material for a supercapacitor, wherein the first cooling step is to naturally cool while maintaining the above air flow.
  7. In paragraph 6, A method for surface modification of a carbon material for a supercapacitor, comprising the step of blocking the air flow and switching to a nitrogen-containing gas atmosphere and performing a second purging for 0.5 to 12 hours after the first cooling step.
  8. In Paragraph 7, A method for surface modification of a carbon material for a supercapacitor, wherein the second purging step is to control the flow of a nitrogen-containing gas at a volumetric flow rate of 50 to 1,000 mL/min.
  9. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein, in the second heat treatment step, the nitrogen-containing gas comprises one or more of NH₃ , HCN, and combinations thereof.
  10. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein, in the second heat treatment step, the nitrogen-containing gas atmosphere has a nitrogen-containing gas concentration in the range of 5 to 30%.
  11. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein the second heat treatment is performed at 800 to 1150°C for 0.5 to 5 hours.
  12. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein the second cooling step is to naturally cool while maintaining the nitrogen-containing gas flow.
  13. In Paragraph 12, A method for surface modification of a carbon material for a supercapacitor, comprising the step of blocking the nitrogen-containing gas flow and switching to an inert gas atmosphere after the second cooling step, and the third purging step for 0.5 to 12 hours.
  14. In Paragraph 13, A method for surface modification of a carbon material for a supercapacitor, wherein the third purging step is to control the inert gas flow at a volumetric flow rate of 50 to 2,000 mL/min.
  15. In Paragraph 13, A method for surface modification of a carbon material for a supercapacitor, wherein the inert gas comprises one or more of N₂ , Ar, and combinations thereof.
  16. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein the specific surface area of the surface-modified carbon material is 2,000 m² /g or more.
  17. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein the oxygen content of the surface-modified carbon material is 6 at% or less based on the total carbon material.
  18. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein the nitrogen content of the surface-modified carbon material is 0.7 at% or more based on the total carbon material.
  19. In paragraph 1, A method for surface modification of a carbon material for a supercapacitor, wherein the surface resistance of the surface-modified carbon material is 300 Ohm/square or less.
  20. Based on the entire surface-modified carbon material, the oxygen concentration is 6 at% or less and the nitrogen concentration is 0.7 at% or more, and A surface-modified carbon material for supercapacitors having a BET (Brunauer-Emmett-Teller) specific surface area of 2,000 m² /g or more.

Description

Modification method of surface of carbon material for supercapacitor and carbon material for supercapacitor surface modified using the same The present embodiments relate to a method for surface modification of a carbon material for a supercapacitor and a carbon material for a supercapacitor surface modified using the same. Unlike lithium-ion batteries (LIBs), the energy storage mechanism of a supercapacitor relies on physical adsorption and desorption reactions. Consequently, although supercapacitors have lower energy density than LIBs, they offer higher power density and superior charge/discharge characteristics. Due to their semi-permanent lifespan, they are widely used as energy storage devices in the energy device market that requires high power output. Therefore, electrode active materials for supercapacitors require a high specific surface area and excellent electrical conductivity to store a large amount of electrolyte ions. Activated carbon is widely used as one such electrode active material. However, as the specific surface area of activated carbon increases, electrical conductivity decreases due to oxidation of the crystal structure, and a large amount of oxygen functional groups are formed at the grain edges, which leads to a problem where the output and lifespan characteristics of supercapacitors using it are degraded. Therefore, it is necessary to develop technology to realize activated carbon with excellent output and lifespan characteristics while improving the specific surface area above a certain level. Figure 1 is an SEM image of a carbon material surface-modified according to Example 1, magnified 5,000 times. Figure 2 is an SEM image of the carbon material raw material according to Comparative Example 1, magnified 5,000 times. Figure 3 is an SEM image of a carbon material surface-modified according to Comparative Example 2, magnified 5,000 times. Figure 4 is an SEM image of a carbon material surface-modified according to Comparative Example 3, magnified 5,000 times. Figure 5 shows the results of X-ray Photoelectron Spectroscopy (XPS) analysis of carbon materials surface-modified according to Example 1 and Comparative Example 3. FIG. 6 schematically illustrates a method for manufacturing a supercapacitor according to one embodiment. FIG. 7 shows the results of measuring supercapacitors manufactured using surface-modified carbon materials according to Comparative Examples 1 to 3 and Example 1 using the constant potential scanning method. (Evaluation scan rate is 10 mV/s) FIG. 8 shows the results of measuring supercapacitors manufactured using surface-modified carbon materials according to Comparative Examples 1 to 3 and Example 1 using the constant potential scanning method. (Evaluation scan rate is 30 mV/s) FIG. 9 shows the results of measuring supercapacitors manufactured using surface-modified carbon materials according to Comparative Examples 1 to 3 and Example 1 using the constant potential scanning method. (Evaluation scan rate is 50 mV/s) FIG. 10 shows the results of measuring supercapacitors manufactured using surface-modified carbon materials according to Comparative Examples 1 to 3 and Example 1 using the constant potential scanning method. (Evaluation scan rate is 100 mV/s) Terms such as first, second, and third are used to describe various parts, components, regions, layers, and/or sections, but are not limited thereto. These terms are used solely to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Accordingly, the first part, component, region, layer, or section described below may be referred to as the second part, component, region, layer, or section without departing from the scope of the present invention. The technical terms used herein are for the reference of specific embodiments only and are not intended to limit the invention. The singular forms used herein include plural forms unless phrases clearly indicate otherwise. As used in the specification, the meaning of "comprising" specifies certain characteristics, areas, integers, steps, actions, elements, and/or components, and does not exclude the presence or addition of other characteristics, areas, integers, steps, actions, elements, and/or components. When it is stated that one part is "above" or "on" another part, it may be directly above or on the other part, or other parts may be involved in between. In contrast, when it is stated that one part is "directly above" another part, no other parts are interposed in between. Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as generally understood by those skilled in the art to which this invention pertains. Terms defined in commonly used dictionaries are further interpreted to have meanings consistent with relevant technical literature and the present disclosure, and are not interpreted in an ideal or highly formal sense unless otherwise d