Metal single-atom catalyst and method for preparing the same

Patent metadata

Field	Value
Publication number	US-2020230589-A1
Application number	US-201916534216-A
Country	US
Kind code	A1
Filing date	Aug 7, 2019
Priority date	Jan 18, 2019
Publication date	Jul 23, 2020
Grant date	—

Abstract

Disclosed are a metal single-atom catalyst and a method for preparing the same. The method uses a minimal amount of chemicals and is thus environmentally friendly compared to conventional chemical and/or physical methods. In addition, the method enables the preparation of a single-atom catalyst in a simple and economical manner without the need for further treatment such as acid treatment or heat treatment. Furthermore, the method is universally applicable to the preparation of single-atom catalysts irrespective of the kinds of metals and supports, unlike conventional methods that suffer from very limited choices of metal materials and supports. Therefore, the method can be widely utilized to prepare various types of metal single-atom catalysts. All metal atoms in the metal single-atom catalyst can participate in catalytic reactions. This optimal atom utilization achieves maximum reactivity per unit mass and can minimize the amount of the metal used, which is very economical.

First claim

What is claimed is:

1 . A method for preparing a metal single-atom catalyst, comprising (a) depositing metal single atoms on a water-soluble support, (b) dispersing the water-soluble support deposited with the metal single atoms and a support, followed by stirring to obtain a dispersion containing a metal single-atom catalyst loaded on the support, and (c) separating the metal single-atom catalyst from the dispersion.

2 . The method according to claim 1 , further comprising drying the water-soluble support under vacuum before step (a).

3 . The method according to claim 1 , wherein the water-soluble support is selected from: sugar powders, including glucose, sucrose, and fructose powders; water-soluble metal salt powders, including sodium chloride, potassium chloride, and sodium bicarbonate powders; water-soluble polymer powders, including PVA and PVP powders; nitrogen-containing carbonaceous materials, including glucosamine, cyanamide, urea, melamine, dopamine, pyrrole, aniline, kinetin, L-alanine, and L-serine; sulfur-containing carbonaceous materials, including cysteine, allicin, alliin, and ajoene; phosphorus-containing carbonaceous materials, including tri(O-tolyl)phosphine, tributylphosphine oxide, tris(dimethylamine)phosphine, trioctylphosphine, trioctylphosphine oxide, and triphenylphosphine; and mixtures of two or more thereof.

4 . The method according to claim 1 , wherein the metal is selected from platinum, gold, palladium, cobalt, silver, rhodium, iridium, ruthenium, nickel, iron, copper, manganese, vanadium, chromium, molybdenum, yttrium, lanthanum, cerium, zirconium, titanium, tantalum, and osmium.

5 . The method according to claim 1 , wherein the metal is selected from gold and silver and the water-soluble support is selected from: nitrogen-containing carbonaceous materials, including glucosamine, cyanamide, urea, melamine, dopamine, pyrrole, aniline, kinetin, L-alanine, and L-serine; sulfur-containing carbonaceous materials, including cysteine, allicin, alliin, and ajoene; phosphorus-containing carbonaceous materials, including tri(O-tolyl)phosphine, tributylphosphine oxide, tris(dimethylamine)phosphine, trioctylphosphine, trioctylphosphine oxide, and triphenylphosphine; and mixtures of two or more thereof.

6 . The method according to claim 1 , wherein the support is selected from carbon-based materials, including carbon black, carbon nanotubes, and graphene, and metal oxides, including titanium dioxide, silica, and alumina.

7 . The method according to claim 1 , wherein the dispersion solvent is anhydrous ethanol.

8 . The method according to claim 1 , wherein the deposition is performed by sputtering.

9 . The method according to claim 8 , wherein the sputtering is radio frequency (RF) magnetron sputtering, the sputtering working pressure is between 0.1 and 1 mTorr, and the intensity of the sputtering power is between 1 and 10 W.

10 . The method according to claim 8 , wherein the deposition by sputtering is performed simultaneously with stirring of the water-soluble support such that the metal single atoms are deposited uniformly over the entire surface of the water-soluble support.

11 . The method according to claim 1 , wherein, in step (c), the dispersion containing a metal single-atom catalyst loaded on the carbon support is filtered, washed with distilled water, and dried to separate the metal single-atom catalyst loaded on the support.

12 . The method according to claim 1 , wherein the metal single-atom catalyst is selected from catalysts for polymer electrolyte membrane fuel cells (PEMFCs), catalysts for phosphoric acid fuel cells (PAFCs), catalysts for alkaline exchange membrane fuel cells (AEMFCs), catalysts for oxygen reduction reaction, catalysts for hydrogen evolution reaction, catalysts for carbon dioxide reduction, catalysts for artificial photosynthesis, and catalysts for electrochemical synthesis.

13 . The method according to claim 1 , wherein the deposition is performed by sputtering, the sputtering is RF magnetron sputtering, the intensity of the sputtering power is between 1 and 10 W, the dispersion solvent is anhydrous ethanol, and the water-soluble support is selected from nitrogen-containing carbonaceous materials, including glucosamine, cyanamide, urea, melamine, dopamine, pyrrole, aniline, kinetin, L-alanine, and L-serine, sulfur-containing carbonaceous materials, including cysteine, allicin, alliin, and ajoene, phosphorus-containing carbonaceous materials, including tri(O-tolyl)phosphine, tributylphosphine oxide, tris(dimethylamine)phosphine, trioctylphosphine, trioctylphosphine oxide, and triphenylphosphine, and mixtures of two or more thereof.

14 . The method according to claim 1 , wherein the water-soluble support is dried under vacuum before step (a); the metal is selected from gold and silver; the water-soluble support is glucosamine; the support is carbon black; the dispersion solvent is anhydrous ethanol; the deposition is performed by RF magnetron sputtering; the sputtering working pressure is between 0.3 and 0.7 mTorr; the intensity of the sputtering power is between 4 and 6 W; the deposition by sputtering is performed simultaneously with stirring of the water-soluble support such that the metal single atoms are uniformly deposited over the entire surface of the water-soluble support; and in step (c), the dispersion containing the metal single-atom catalyst loaded on the carbon support is filtered, washed with distilled water, and dried to separate the metal single-atom catalyst loaded on the support.

Assignees

• Korea Inst Sci & Tech
• Global Frontier Ct Multiscale Energy Systems

Inventors

• Yoo Sung Jong
• Jang Injoon
• Park Hee-Young
• Lee So Young
• Park Hyun Seo
• Kim Jin Young
• Jang Jong Hyun
• Kim Hyoung-Juhn

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/34

  Mechanical properties · CPC title

• B01J35/70

  characterised by their crystalline properties, e.g. semi-crystalline (catalysts comprising carbon B01J21/18; molecular sieves B01J29/00) · CPC title

• B01J37/344

  of electromagnetic wave energy · CPC title