KR-102962864-B1 - METHOD FOR MANUFACTURING CATALYST FOR OXYGEN EVOLUTION REACTION AND CATALYST FOR OXYGEN EVOLUTION REACTION MANUFACTURED THEREFROM

Abstract

The present invention relates to a method for manufacturing a catalyst for an oxygen evolution reaction, a catalyst for an oxygen evolution reaction manufactured therefrom, and an oxygen evolution electrode comprising such catalyst for an oxygen evolution reaction. More specifically, the invention provides a method for manufacturing a cobalt-iron-based catalyst with improved electrochemical performance by introducing oxygen deficiency under a non-strict atmosphere.

Inventors

• 최승목
• 허성준
• 이주영
• 정재훈
• 김치호
• 명신우
• 정재엽
• 진송

Assignees

• 한국재료연구원

Dates

Publication Date

20260512

Application Date

20231215

Claims (8)

1. Step of preparing cobalt hydroxide powder and iron hydroxide powder; A step of introducing the mixed powder of the above cobalt hydroxide powder and iron hydroxide powder and a plurality of balls into a milling vessel; and A method for preparing a catalyst for an oxygen evolution reaction, comprising the step of ball-milling the above-mentioned mixed powder in an air atmosphere to obtain cobalt oxide-iron oxide composite nanoparticles.
2. In claim 1, A method for preparing a catalyst for an oxygen evolution reaction, wherein the above-mentioned cobalt oxide-iron oxide composite nanoparticles have a heterogeneous core-shell structure in which cobalt oxide surrounds a portion of the surface of the iron oxide nanoparticles.
3. In claim 1, A method for manufacturing a catalyst for an oxygen evolution reaction, wherein the step of preparing the above-mentioned cobalt hydroxide powder and iron hydroxide powder is by a precipitation method.
4. In claim 1, A method for manufacturing a catalyst for an oxygen evolution reaction, wherein the molar ratio of cobalt hydroxide powder and iron hydroxide powder included in the above-mentioned mixed powder is 1:1 to 4:1.
5. In claim 1, A method for manufacturing a catalyst for an oxygen evolution reaction, wherein the ball milling is performed for 2 hours or more and 4 hours or less.
6. Manufactured by a method according to any one of claims 1 to 5, and A catalyst for an oxygen evolution reaction comprising cobalt oxide-iron oxide composite nanoparticles having a heterogeneous core-shell structure in which a portion of the surface of the iron oxide nanoparticles is surrounded by cobalt oxide.
7. An oxygen evolution reaction catalyst according to claim 6, wherein at least one of the cobalt oxide and iron oxide comprises oxygen deficiency, and the oxygen deficiency of the oxygen evolution reaction catalyst is 50% or more and 60% or less.
8. Oxygen generating electrode comprising a catalyst for an oxygen generating reaction according to claim 6.

Description

Method for manufacturing a catalyst for oxygen evolution reaction and a catalyst for oxygen evolution reaction manufactured therefrom The present invention relates to a method for manufacturing a catalyst for an oxygen evolution reaction, a catalyst for an oxygen evolution reaction manufactured therefrom, and an oxygen evolution electrode comprising such catalyst for an oxygen evolution reaction. More specifically, the invention relates to a method for manufacturing a cobalt-iron-based catalyst with improved electrochemical performance by introducing oxygen deficiency under a non-strict atmosphere. Electrolysis is a technology that electrochemically produces hydrogen by utilizing the electrolysis of water. As the demand for new and renewable energy increases due to the acceleration of global warming, significant research and development are being conducted on electrolysis technology capable of supplying high-purity hydrogen in an eco-friendly manner in fields that utilize hydrogen as an energy source, such as hydrogen fuel cells and hydrogen direct combustion engines. The electrochemical decomposition of water consists of two half-reactions: the Hydrogen Evolution Reaction (HER) and the Oxygen Evolution Reaction (OER). The Hydrogen Evolution Reaction occurs at the cathode, and the Oxygen Evolution Reaction occurs at the anode. Transition metal-based metal oxides possess a wide range of oxidation states, making them highly advantageous for redox reactions. Furthermore, since transition metals are cheaper and more abundant than precious metals, active research is being conducted on them as catalytic materials for oxygen evolution reactions. Meanwhile, when oxygen vacancies exist in metal oxides, electrons can accumulate at the vacancy sites, and the adsorption and desorption of oxygen intermediates due to electron accumulation can be facilitated, thereby improving performance as an oxygen generation catalyst. Conventional methods for introducing such oxygen vacancies into metal oxides, such as plasma treatment using high voltage or heat treatment, have been proposed; however, since these methods must be performed under strict atmospheric conditions, such as high temperatures of 800°C or higher, an inert gas atmosphere, or a vacuum atmosphere, there have been problems with poor productivity and economic feasibility in terms of commercialization. FIG. 1 is a diagram briefly illustrating a method for manufacturing a catalyst for an oxygen generation reaction according to one embodiment of the present invention. Figure 2 is a diagram showing the HAADF image and EDS elemental mapping image for the catalyst prepared in Example 1. Figure 3 is a figure showing the XRD patterns of the catalysts prepared in Examples 1 to 3 and Comparative Example 3. Figure 4 is a diagram showing the XRD spectra of the catalysts prepared in Examples 1 to 3, magnified in the 2θ range of 35° to 40°. Figure 5 is a figure showing the XRD spectrum of cobalt oxide obtained using the catalyst prepared in Example 1 and Comparative Example 3 and the co-precipitation method. Figure 6 is a figure showing the XPS analysis results for the catalysts prepared in Examples 1 to 3. FIG. 7 is a figure showing the oxygen deficiency (a) and Co3 + /Co2 + ratio (b) for the catalysts prepared in Examples 1 to 3. FIG. 8 is a polarization curve for the oxygen evolution reaction of an electrode containing the catalysts prepared in Examples 1 to 3 and Comparative Examples 1 to 3. FIG. 9 is a diagram showing the results of an electrode durability test including the catalysts prepared in Examples 1 to 3 and Comparative Example 3. Figure 10 is a diagram showing the current density according to the change in electrolyte temperature of a water electrolysis device including an electrode containing the catalyst prepared in Example 1. Figure 11 is a diagram showing the results of a durability test for a water electrolysis device including an electrode containing the catalyst prepared in Example 1. Throughout 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. Throughout this specification, when a component is described as being located "on" another component, this includes not only cases where a component is in contact with another component, but also cases where another component exists between the two components. Throughout the entire specification, the unit "parts by weight" may refer to the ratio of weight between each component. Throughout this specification, "A and/or B" means "A and B, or A or B". Throughout the present specification, oxygen deficiency refers to a percentage value calculated by separating the oxygen peak in the oxygen O s1 spectrum of XPS into a metal-oxygen peak (530.7 eV) and an oxygen deficiency peak (531.8 eV), and then dividing the area of the oxygen deficiency peak by the sum of the a