KR-20260066829-A - BIFUNCTIONAL ELECTROCATALYST USING WASTE AND ITS MANUFACTURING METHOD

Abstract

The present invention relates to a dual-functional electrocatalyst using waste and a method for manufacturing the same. Specifically, it relates to a dual-functional electrocatalyst using waste that has dual functionality in hydrogen evolution (HER) and oxygen evolution (OER) reactions by recycling waste to obtain a metal, and a method for manufacturing the same.

Inventors

• 김상재
• 케이루 세르바라 베지고

Assignees

• 제주대학교 산학협력단

Dates

Publication Date

20260512

Application Date

20241105

Claims (13)

1. A dual-functional electrocatalyst using waste, comprising a nitrogen-doped carbon material; and a metal distributed on the nitrogen-doped carbon material.
2. In claim 1, The above metal is A dual-functional electrocatalyst using waste, comprising a first metal and a first metal oxide.
3. In claim 1, A dual-functional electrocatalyst using waste, wherein the metal is one selected from the group consisting of cobalt (Co), copper (Cu), iron (Fe), nickel (Ni) and manganese (Mn).
4. In claim 3, A dual-functional electrocatalyst using waste, wherein the metal is iron (Fe).
5. In claim 2, A dual-functional electrocatalyst using waste, wherein the first metal is iron (Fe) and the first metal oxide is Fe₃O₄ .
6. In claim 1, The above metal is a dual-functional electrocatalyst using waste, obtained from a waste heat pack (WHP).
7. In claim 1, The above-mentioned electrocatalyst is a dual-functional electrocatalyst using waste, wherein carbon (C) is 90% or more of the total composition of 100% by weight.
8. In claim 1, The above-mentioned electrocatalyst is a dual-functional electrocatalyst using waste, wherein iron (Fe) is 0.05% or more and 0.2% or less based on 100% by weight of the total composition.
9. In claim 1, The above-mentioned electrocatalyst is a dual-functional electrocatalyst using waste, wherein the nitrogen (N) content is 0.2% or more and 2.0% or less based on 100% by weight of the total composition.
10. The electrocatalyst according to any one of claims 1 to 9 is A dual-functional electrocatalyst using waste materials, used as a catalyst in hydrogen evolution reactions (HER) and oxygen evolution reactions (OER).
11. A step of recovering metal from a waste heat pack (WHP); A step of preparing a mixture by reacting the above metal with hydrochloric acid; and A method for manufacturing a dual-functional electrocatalyst using waste, comprising the step of annealing the above mixture including carbon material and nitrogen material.
12. In claim 11, A method for manufacturing a dual-functional electrocatalyst using waste, wherein the carbon material is selected from the group consisting of carbon black, carbon nanotubes, graphene, carbon fibers, glassy carbon, and the same.
13. In claim 11, A method for manufacturing a dual-functional electrocatalyst using waste, wherein the annealing temperature is 700 ℃ or higher and 1,000 ℃ or lower.

Description

Bifunctional Electrocatalyst Using Waste and Method for Manufacturing the Same The present invention relates to a dual-functional electrocatalyst using waste and a method for manufacturing the same. Specifically, it relates to a dual-functional electrocatalyst using waste that has dual functionality in hydrogen evolution (HER) and oxygen evolution (OER) reactions by recycling waste to obtain a metal, and a method for manufacturing the same. The energy sector is gradually shifting toward the utilization of renewable resources, a trend being realized through high-efficiency devices such as fuel cells, metal-air batteries, and water splitters. In particular, hydrogen production through water splitting processes has established itself as a key method for sustainable hydrogen production by utilizing electrochemical redox reactions to produce hydrogen evolution reactions (HER) and oxygen evolution reactions (OER). Meanwhile, since the hydrogen evolution (HER) and oxygen evolution (OER) reactions in water splitting are slow, effective electrocatalysts are required to facilitate the smooth progress of these reactions. Currently, platinum group metal (PGM)-based electrocatalysts such as Pt, IrO₂, and RuO₂ are widely recognized as benchmark catalysts for the hydrogen evolution (HER) and oxygen evolution (OER), respectively; however, these metal catalysts have several limitations. Pt is oxidized at high potentials, leading to performance degradation in OER, whereas RuO₂ exhibits excellent performance in OER but fails to serve as an optimal catalyst for HER. The high cost, limited functionality, and insufficient stability of these PGM-based catalysts can be major obstacles to the development of water splitting technology. In addition, for electrochemical devices to operate efficiently in various operating environments, dual-functional electrocatalysts capable of exhibiting catalytic activity in both HER and OER are essential. However, in existing single-operation systems, using various catalysts results in high manufacturing costs and requires complex manufacturing procedures, which reduces practicality. Accordingly, there is a need for research aimed at reducing costs and improving operational efficiency by developing efficient dual-functional electrocatalysts. Furthermore, the development of electrocatalysts that can contribute to environmental protection and resource conservation should also be considered. Figure 1(a) is a schematic diagram of a method for synthesizing a dual-functional electrocatalyst using a waste heat pack (WHP), (b) is an XRD pattern of an electrocatalyst in one embodiment of the present invention, (c) is a Raman spectrum of an electrocatalyst in one embodiment of the present invention, (d) is a BET analysis of an electrocatalyst in one embodiment of the present invention, and (e) is a comparison of the cost of an electrocatalyst in one embodiment of the present invention. Figure 2 shows the pore size distribution of an electrocatalyst, which is an embodiment of the present invention. Figures 3 (a) and (b) are FESEM images of an electrocatalyst in one embodiment of the present invention, (c) and (d) are TEM images of an electrocatalyst in one embodiment of the present invention, and (e) and (f) are HRTEM images of an electrocatalyst in one embodiment of the present invention. FIG. 4 is a high-resolution XPS spectrum graph for (a) Fe 2p, (b) N 1s, (c) C 1s and (d) O 1s of an electrocatalyst in one embodiment of the present invention. Figure 5 shows (a) the OER polarization curve, (b) the overpotential evaluated at various current densities, (c) the Tafel slope, (d) the HER polarization curve, (e) the overpotential at various current densities, and (f) the Tafel slope, the LSV curves of OER and HER for both actual and ideal catalysts (g), the chronopotentiometric analysis of Fe/ Fe₃O₄ /NC for OER and HER at 50 and -50 mA cm⁻² , respectively (h), and the EIS spectrum measured at 1.53 V versus RHE (inset: EIS circuit fitting for the red curve) (i). Figure 6 shows the LSV curve (a), chronopotentiometer analysis (b), the LSV curve after initial and stability tests of Fe/ Fe₃O₄ / NC(-, +) (c), and the rate stability analysis at various current densities (d). It also shows the Faraday efficiency of Fe/ Fe₃O₄ /NC for HER(e) and OER(f), and a comparison of water splitting performance (g) in terms of the cell voltage required to achieve a current density of 10 mA cm⁻² for recently reported iron-based catalysts. In this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. In this specification, "A and/or B" means "A and B, or A or B". In this specification, when a component is described as being "on" one component, this means that, unless specifically stated otherwise, other components may be placed in between, without excluding the placement of other com