Method of producing core-shell catalyst

Patent metadata

Field	Value
Publication number	US-2016359171-A1
Application number	US-201615170075-A
Country	US
Kind code	A1
Filing date	Jun 1, 2016
Priority date	Jun 2, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

A copper-coated palladium-containing particle dispersion in which copper-coated palladium-containing particles, which are obtained by coating surfaces of palladium-containing particles with copper, are dispersed is prepared, a platinum ion-containing solution is prepared, and a shell is formed by mixing the copper-coated palladium-containing particle dispersion and the platinum ion-containing solution with each other in a microreactor to displace copper of the copper-coated palladium-containing particle surfaces with platinum. The microreactor includes at least a first supply flow path, a second supply flow path, a joint portion in which the first supply flow path and the second supply flow path are joined to each other, and a discharge flow path. An orifice portion is provided midway in the discharge flow path. A pressure applied to the orifice portion in the displacement step is 2 MPa or higher.

First claim

What is claimed is:

1 . A method of producing a core-shell catalyst,
the core-shell catalyst including a core containing palladium, and a shell containing platinum with which the core is coated, the method comprising: a step of preparing a copper-coated palladium-containing particle dispersion in which copper-coated palladium-containing particles, which are obtained by coating surfaces of palladium-containing particles with copper, are dispersed; a step of preparing a platinum ion-containing solution; and a displacement step of forming the shell by mixing the copper-coated palladium-containing particle dispersion and the platinum ion-containing solution with each other in a microreactor to displace copper of the copper-coated palladium-containing particle surfaces with platinum, wherein the microreactor includes a first supply flow path, a second supply flow path, a joint portion in which the first supply flow path and the second supply flow path are joined to each other, and a discharge flow path, an orifice portion is provided midway in the discharge flow path, and a pressure applied to the orifice portion in the displacement step is 2 MPa or higher.

2 . The method according to claim 1 , wherein
the orifice portion is a cross nozzle.

3 . The method according to claim 1 , wherein
the palladium-containing particles are supported on a support.

Assignees

• Toyota Motor Co Ltd

Inventors

• Ishikawa Shotaro

Classifications

• B22F1/17

  Metallic particles coated with metal · CPC title

• H01M4/8657 Primary

  layered · CPC title

• H01M4/92

  Metals of platinum group (H01M4/94 {, H01M4/9058} take precedence) · CPC title

• C23C18/1682

  Control of atmosphere · CPC title

• C23C18/1619

  Apparatus for electroless plating · CPC title