JP-7855184-B2 - Carbon materials, methods for producing carbon materials, catalysts, dispersions, electrodes, batteries, and electrolysis apparatuses

Inventors

• 坂本 圭亮
• 安井 健悟
• 白石 康浩
• 平井 隆之

Assignees

• ＤＩＣ株式会社
• 国立大学法人大阪大学

Dates

Publication Date

20260508

Application Date

20240321

Priority Date

20230406

Claims (16)

1. It contains a calcined product of a mixture containing the first compound and the second compound, The first compound is a phthalocyanine compound having bromine and chlorine as substituents. The second compound is a compound containing at least one metal element selected from the group consisting of Fe, Co, Ni, Cu, Al, and Zn. The phthalocyanine compound contains Fe, Co, Ni, Cu, or Zn as the central metal. The average bromine number of the phthalocyanine compound is 4 or more and less than 16. The average number of chlorine atoms in the phthalocyanine compound is greater than 0 and 11 or less. The average halogen number of the phthalocyanine compound is 8 or more and 16 or less. A carbon material with a BET specific surface area of 100 to 2000 m² /g.
2. The carbon material according to claim 1, wherein the phthalocyanine compound contains Fe, Co, or Zn as the central metal.
3. The carbon material according to claim 1, wherein the phthalocyanine compound contains Zn as the central metal.
4. The phthalocyanine compound is in powder form, The carbon material according to claim 1, wherein the average particle size of the powder comprising the phthalocyanine compound is 300 nm or less.
5. The carbon material according to claim 1, wherein the second compound is a phthalocyanine compound or a porphyrin compound that does not have bromine as a substituent.
6. The carbon material according to claim 1, wherein the second compound is a compound containing Fe.
7. The carbon material according to claim 1, wherein the mass ratio of the content of the first compound to the content of the second compound in the mixture is 0.1 to 2000.
8. A method for producing a carbon material according to any one of claims 1 to 7 , A method for producing a carbon material, comprising the step of calcining a raw material containing the first compound and the second compound.
9. A catalyst used in the reduction reaction of oxygen, comprising a carbon material according to any one of claims 1 to 7 .
10. A dispersion containing a carbon material according to any one of claims 1 to 7 and a dispersion medium for the carbon material.
11. The dispersion according to claim 10 , comprising a polymer electrolyte.
12. The dispersion according to claim 10 , used for forming an electrode catalyst layer.
13. An electrode comprising an electrode catalyst layer containing the carbon material described in any one of claims 1 to 7 .
14. The electrode according to claim 13 , wherein the electrode catalyst layer contains a polymer electrolyte.
15. A battery comprising the electrode described in claim 13 .
16. An electrolysis apparatus comprising the electrodes described in claim 13 .

Description

This disclosure relates to carbon materials, methods for producing carbon materials, catalysts, dispersions, electrodes, batteries, and electrolysis apparatus. Carbon materials are used in a wide range of applications due to their properties such as high electrical conductivity, high thermal conductivity, low thermal expansion coefficient, lightness, and heat resistance. In recent years, the use of nitrogen-containing carbon materials as catalysts (oxygen reduction catalysts) for the positive electrodes of fuel cells and air batteries has been investigated (see Patent Document 1). Furthermore, nitrogen-containing carbon materials may possess carbon dioxide reduction activity or nitrogen reduction activity, and are attracting attention as catalysts (carbon dioxide reduction catalysts or nitrogen reduction catalysts) for the cathodes of electrolysis devices (see Non-Patent Documents 1 and 2). Japanese Patent Publication No. 2012-101155International Publication No. 2021/220495 Angew. Chem. Int. Ed. , 2015, 54, 10758-10762Nature Communications, 2019, 10, 341-348 In this specification, numerical ranges indicated using "~" represent a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. Furthermore, unless otherwise explicitly stated, the units of the numbers before and after "~" are the same. In numerical ranges described in stages within this specification, the upper or lower limit of one stage of the range may be replaced with the upper or lower limit of another stage. Also, in numerical ranges described within this specification, the upper or lower limit of that range may be replaced with the values shown in the examples (experimental examples). Furthermore, individually described upper and lower limits can be combined in any way. Preferred embodiments of this disclosure are described below. However, this disclosure is not limited to the embodiments described below. <Carbon materials> One embodiment of the present disclosure is a carbon material containing a calcined product of a mixture comprising a first compound and a second compound, wherein the first compound is a phthalocyanine compound having bromine (Br) as a substituent (hereinafter also referred to as a "brominated phthalocyanine compound"), and the second compound is a compound containing at least one metal element selected from the group consisting of Fe, Co, Ni, Cu, Al, and Zn. The second compound is a different compound from the first compound, for example, a compound that does not contain bromine (Br). The carbon material described above, containing the calcined product of the above mixture, exhibits excellent oxygen reduction activity. Therefore, it can be used as a catalyst for oxygen reduction reactions (oxygen reduction catalyst), and is used, for example, as a positive electrode catalyst in fuel cells, air batteries, etc. The carbon material can also sometimes be used as a cathode catalyst in oxygen electrolysis devices. Furthermore, because the carbon material tends to exhibit carbon dioxide reduction activity and nitrogen reduction activity, it may also be usable as a catalyst for carbon dioxide reduction reactions (carbon dioxide reduction catalyst) and nitrogen reduction reactions (nitrogen reduction catalyst). Specific applications include, for example, cathode catalysts in carbon dioxide electrolysis devices and nitrogen electrolysis devices. The oxygen reduction activity, carbon dioxide reduction activity, and nitrogen reduction activity of the carbon material can be confirmed by the method described in the Examples (Experimental Examples). The first compound, a brominated phthalocyanine compound, has a structure represented by, for example, the following formula (1) or formula (2). In formulas (1) and (2), X1 to X16 each independently represent a hydrogen atom or a halogen atom, provided that at least one of X1 to X16 is a bromine atom. In formula (2), M represents the central metal. Examples of central metals (M) include Fe, Co, Ni, Cu, and Zn. Phthalocyanine compounds containing a central metal are sometimes referred to using a prefix corresponding to the type of central metal, such as "iron phthalocyanine" (central metal: Fe), "cobalt phthalocyanine" (central metal: Co), "copper phthalocyanine" (central metal: Cu), and "zinc phthalocyanine" (central metal: Zn). The brominated phthalocyanine compound does not necessarily have the above-mentioned central metal (M), but when the brominated phthalocyanine compound has the above-mentioned central metal (M), superior oxygen reduction activity, carbon dioxide reduction activity, and nitrogen reduction activity are more likely to be obtained. From the viewpoint of obtaining even better oxygen reduction activity, the brominated phthalocyanine compound may contain Fe, Co, or Zn as the central metal (M), and from the viewpoint of obtaining even better oxygen reduction activity, it may contain Zn. The halogen atom may consist solely of a brom