KR-102963358-B1 - Carbon material doped with nitrogen and sulfur manufactured using thermal plasma and graphene ink using the material

Abstract

The present invention relates to a method for manufacturing a carbon material doped with nitrogen and sulfur through thermal plasma treatment, a material manufactured through the method, and a graphene ink using the material.

Inventors

• 최선용
• 손병구
• 신명선
• 이규항
• 이순직
• 연정미
• 오성택

Assignees

• 재단법인 철원플라즈마 산업기술연구원

Dates

Publication Date

20260508

Application Date

20201230

Claims (12)

1. A method for manufacturing nitrogen and sulfur-doped carbon materials, A step of preparing a carbon solid-phase raw material, ammonia which is a gaseous-phase raw material containing nitrogen (N), a solid-phase raw material containing nitrogen (N), and a solid-phase raw material containing sulfur (S); A step of introducing the carbon solid-phase raw material, the solid-phase raw material containing nitrogen (N), and the solid-phase raw material containing sulfur (S) into a thermal plasma reactor, wherein the ammonia is introduced at a rate of 10 LPM or more and 20 LPM or less, wherein carbon is included in an amount of 72 wt% or more and 85 wt% or less of the total raw material, nitrogen is included in an amount of 11 wt% or more and 20 wt% or less of the total raw material, and sulfur is included in an amount of 4 wt% or more and less than 11 wt% of the total raw material; A step of forming a plasma state under a process temperature of 5,000K or higher and 20,000K or lower and a process pressure of 300 torr or higher and 600 torr or lower, wherein, the nitrogen-containing raw material and the sulfur-containing raw material become a plasma state, wherein, in the carbon solid-phase raw material, some of the carbon sp2 bonds are broken to create a defect; A step of doping nitrogen and sulfur in a plasma state under a process temperature of 1500K or higher and 2500K or lower and a process pressure of 300 torr or higher and 600 torr or lower, wherein the nitrogen and sulfur in a plasma state are doped into defects of a carbon solid-phase raw material; and A method comprising the step of obtaining the above nitrogen and sulfur-doped carbon material.
2. In Article 1, A method in which the above-mentioned carbon solid-phase raw material comprises at least one of graphene, expandable graphite, or graphene oxide.
3. In Article 1, A method characterized by physically mixing the carbon solid-phase raw material, the solid-phase raw material containing nitrogen (N), and the solid-phase raw material containing sulfur (S) and introducing them into a thermal plasma reactor.
4. In Article 1, The solid raw material containing nitrogen (N) comprises at least one of urea (CH4N2O) or melamine (C3H6N6), and A method in which the solid-phase raw material containing the above sulfur (S) comprises at least one of methylsulfonyl methane (C2H6O2S) or sulfur powder.
5. In Paragraph 4, A method in which the solid raw material containing nitrogen (N) and the solid raw material containing sulfur (S) are each urea and sulfur powder.
6. In Article 1, A method characterized in that, in the above-mentioned input step, the raw material is introduced by a carrier gas.
7. In Paragraph 6, A method characterized in that the carrier gas is argon.
8. A method according to claim 1, characterized in that the method is performed in a time of 0.01 seconds to 5 seconds.
9. A nitrogen and sulfur-doped carbon material manufactured by the method of claim 1, The above carbon material has a two-dimensional planar structure composed of sp2 covalent bonds between carbon-carbon, carbon-nitrogen, and carbon-sulfur atoms, and The above carbon material is It contains carbon in an amount of 72 wt% or more and 88 wt% or less of the total material weight, and Contains nitrogen in an amount of 8 wt% or more and 20 wt% or less of the total material weight, and Containing sulfur at a concentration of 4 wt% or more and 8 wt% or less of the total material weight Nitrogen and sulfur-doped carbon material.
10. The nitrogen and sulfur-doped carbon material of claim 9; and water or organic solvent Conductive graphene ink containing
11. In claim 10, the ink is a graphene ink having a conductivity of 900 Scm⁻¹ to 1100 Scm⁻¹ when printed with a line width of 30 μm and a thickness of 10 μm.
12. Graphene ink according to claim 10, characterized in that the organic solvent is ethanol.

Description

Carbon material doped with nitrogen and sulfur manufactured using thermal plasma and graphene ink using the material The present application relates to a method for functionalizing a carbon material using thermal plasma treatment, a material produced through the method, and an ink using the material. Specifically, the application relates to a method for doping nitrogen and sulfur into a carbon material through thermal plasma treatment, a material produced through the method, and a graphene ink using the material. graphene, graphite, fullene, nanotubes, nanofibers, etc. Carbon materials are substances that possess a combination of the characteristics of traditional materials such as metals, chemicals, and ceramics, and can be applied in various fields including semiconductors, capacitors, secondary batteries, biotechnology, and medicine. Among them, graphene is an outstanding new material with excellent electrical and mechanical properties, such as high electrical conductivity and high strength, and there is fierce global competition for its technological development. In industries requiring conductivity, such as printed electronics and films, highly electrically conductive materials like silver or copper are dispersed in aqueous, alcohol-based, or organic solvents to form inks or pastes. These are then used by printing or filming, and the solvents are removed by evaporation. Currently, the most widely used conductive ink material is silver, a precious metal. Consequently, it has the disadvantage of being expensive. The present invention was completed by developing a highly conductive graphene ink in which nitrogen and sulfur are doped into graphene using thermal plasma to impart higher conductivity, thereby solving these problems with a conductive graphene ink. Figure 1 is a schematic diagram of a method for doping nitrogen and sulfur into a carbon material using thermal plasma. Figure 2 is a schematic diagram of the bonding forms of carbon and nitrogen in doped graphene. Figure 3 shows the results of EDS analysis of nitrogen and sulfur-doped graphene according to changes in doping raw material input amount and process pressure. Figure 4 shows the XRD analysis of nitrogen and sulfur-doped graphene using thermal plasma. Figure 5 shows the RAMAN analysis of nitrogen and sulfur-doped graphene using thermal plasma. Figure 6 shows the XPS analysis of nitrogen and sulfur-doped graphene using the conditions of plasma 1. Figure 7 shows the XPS analysis of nitrogen and sulfur-doped graphene using the conditions of plasma 2. Figure 8 shows the XPS analysis of nitrogen and sulfur-doped graphene using the conditions of plasma 3. Figure 9 shows the resistance of nitrogen and sulfur-doped graphene ink. Figure 10 compares the conductivity of nitrogen and sulfur-doped graphene ink, graphene ink, nitrogen-only doped graphene ink, and sulfur-only doped graphene ink. Figure 11 compares the EMI shielding efficiency of nitrogen and sulfur-doped graphene ink, graphene ink, nitrogen-only doped graphene ink, and sulfur-only doped graphene ink. To describe the contents disclosed herein, various terms will be defined in this specification. In addition to these terms, other terms are defined elsewhere in this specification where necessary. Unless otherwise explicitly defined herein, industry terms used herein shall have the meanings recognized in the industry. In case of conflict, the definitions in this specification shall prevail. Problems with conventional technology regarding carbon materials Carbon materials such as graphene, graphite, fullene, nanotubes, and nanofibers are materials that possess a combination of the characteristics of traditional materials such as metals, chemicals, and ceramics, and can be applied in various fields such as semiconductors, capacitors, secondary batteries, bio, and medicine. In one embodiment of the present application, the carbon raw material may be graphene, graphite, expandable graphite, or graphene oxide among the carbon materials. The graphene described above consists of carbon atoms connected in a single layer to form a hexagonal planar structure, and is structurally and chemically stabilized. However, due to its stable chemical structure, it faces difficulties in application caused by high contact resistance, low dispersibility, and poor adhesion, making it challenging to fully utilize the high electrical conductivity inherent in graphene. To address these issues, graphene can be used for specific applications and purposes by attaching functional groups. In this context, attachment refers to a form of bonding achieved through the chemical sharing of electron pairs. The aforementioned functional group refers to an atomic group or bonding mode that is the cause of a characteristic within a group of organic compounds that share common chemical properties. Wet method Previously, wet methods were mainly used to attach functional groups to graphene. This method involves using strong acids to br