Patents by Inventor Koshi Sekizawa

Koshi Sekizawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10431831
    Abstract: A catalyst particle is composed of an inner particle and an outermost layer that includes platinum and covers the inner particle. The inner particle includes on at least a surface thereof a first oxide having an oxygen defect.
    Type: Grant
    Filed: April 13, 2017
    Date of Patent: October 1, 2019
    Assignees: Toyota Jidosha Kabushiki Kaisha, University of Miyazaki
    Inventors: Go Sakai, Tatsuya Arai, Tetsuya Ogawa, Koshi Sekizawa, Naoki Takehiro
  • Publication number: 20170282171
    Abstract: A catalyst particle is composed of an inner particle and an outermost layer that includes platinum and covers the inner particle. The inner particle includes on at least a surface thereof a first oxide having an oxygen defect.
    Type: Application
    Filed: April 13, 2017
    Publication date: October 5, 2017
    Applicants: Toyota Jidosha Kabushiki Kaisha, University of Miyazaki
    Inventors: Go Sakai, Tatsuya Arai, Tetsuya Ogawa, Koshi Sekizawa, Naoki Takehiro
  • Patent number: 8815470
    Abstract: It is a main object of the present invention to provide a fuel cell catalyst in which a support for supporting a metal catalyst has electrical conductivity in itself and which can prevent agglomeration of the metal catalyst during long term use of the fuel cell. In the present invention, the object is achieved by providing a fuel cell catalyst for use in a cathode-side catalyst electrode layer of a solid polymer electrolyte fuel cell, comprising a metal catalyst and a perovskite-type complex oxide (ABO3).
    Type: Grant
    Filed: February 24, 2006
    Date of Patent: August 26, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Koshi Sekizawa, Haruyuki Nakanishi
  • Publication number: 20140200133
    Abstract: The present invention provides core-shell type metal nanoparticles having a high surface coverage of the core portion with the shell portion, and a method for producing the same. Disclosed is core-shell type metal nanoparticles comprising a core portion comprising a core metal material and a shell portion covering the core portion, wherein the core portion substantially has no {100} plane of the core metal material on the surface thereof.
    Type: Application
    Filed: March 14, 2014
    Publication date: July 17, 2014
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hiroko KIMURA, Naoki TAKEHIRO, Koshi SEKIZAWA, Atsuo IIO, Tatsuya ARAI
  • Patent number: 8735019
    Abstract: A fuel cell including a single fuel cell which includes a membrane electrode including a polymer electrolyte membrane, an anode electrode on one surface of the polymer electrolyte membrane, and a cathode electrode on another surface of the polymer electrolyte membrane, the anode electrode including an anode catalyst layer and a gas diffusion layer and the cathode electrode including a cathode catalyst layer and a gas diffusion layer. At least one of the anode cathode catalyst layers includes core-shell type catalyst particles, each having a core and a shell covering the core and including a shell metallic material. At least one of the polymer electrolyte membrane, anode catalyst layer, gas diffusion layer at the anode side, cathode catalyst layer and gas diffusion layer at the cathode side includes metallic nanoparticles having an average particle diameter different from that of the core-shell type catalyst particles and including the shell metallic material.
    Type: Grant
    Filed: April 7, 2010
    Date of Patent: May 27, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tatsuya Arai, Naoki Takehiro, Atsuo Iio, Koshi Sekizawa, Hiroko Kimura
  • Publication number: 20130189607
    Abstract: A catalyst particle is composed of an inner particle and an outermost layer that includes platinum and covers the inner particle. The inner particle includes on at least a surface thereof a first oxide having an oxygen defect.
    Type: Application
    Filed: October 6, 2011
    Publication date: July 25, 2013
    Inventors: Go Sakai, Tatsuya Arai, Tetsuya Ogawa, Koshi Sekizawa, Naoki Takehiro
  • Publication number: 20130059219
    Abstract: A fuel cell system which prevents a reduction in catalyst activity, wherein at least one of the anode catalyst layer and the cathode catalyst layer includes a core-shell type catalyst particle having a core portion including a core metallic material and a shell portion covering the core portion and including a shell metallic material; and wherein the fuel cell system has: a means for storing an initial value of a ratio of the core metallic material to a surface area of the core-shell type catalyst particle, and a means for determining whether or not the ratio of the core metallic material to the surface area of the core-shell type catalyst particle is increased at a predetermined stage, compared to the initial value.
    Type: Application
    Filed: May 25, 2010
    Publication date: March 7, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hiroko Kimura, Atsuo Iio, Naoki Takehiro, Tatsuya Arai, Koshi Sekizawa
  • Publication number: 20130029842
    Abstract: The present invention provides core-shell type metal nanoparticles having a high surface coverage of the core portion with the shell portion, and a method for producing the same. Disclosed is core-shell type metal nanoparticles comprising a core portion comprising a core metal material and a shell portion covering the core portion, wherein the core portion substantially has no {100 } plane of the core metal material on the surface thereof.
    Type: Application
    Filed: April 7, 2010
    Publication date: January 31, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hiroko Kimura, Naoki Takehiro, Koshi Sekizawa, Atsuo Iio, Tatsuya Arai
  • Publication number: 20130029248
    Abstract: A fuel cell including a single fuel cell which includes a membrane electrode including a polymer electrolyte membrane, an anode electrode on one surface of the polymer electrolyte membrane, and a cathode electrode on another surface of the polymer electrolyte membrane, the anode electrode including an anode catalyst layer and a gas diffusion layer and the cathode electrode including a cathode catalyst layer and a gas diffusion layer. At least one of the anode cathode catalyst layers includes core-shell type catalyst particles, each having a core and a shell covering the core and including a shell metallic material. At least one of the polymer electrolyte membrane, anode catalyst layer, gas diffusion layer at the anode side, cathode catalyst layer and gas diffusion layer at the cathode side includes metallic nanoparticles having an average particle diameter different from that of the core-shell type catalyst particles and including the shell metallic material.
    Type: Application
    Filed: April 7, 2010
    Publication date: January 31, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tatsuya Arai, Naoki Takehiro, Atsuo Iio, Koshi Sekizawa, Hiroko Kimura
  • Publication number: 20120208105
    Abstract: Disclosed is a catalyst particle having high catalyst activity and a method for producing the catalyst particle. A catalyst particle comprising a core particle which contains a palladium alloy and an outermost layer which contains platinum, wherein an interlayer comprising only palladium as a simple substance is present between the core particle and the outermost layer.
    Type: Application
    Filed: July 21, 2010
    Publication date: August 16, 2012
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tatsuya Arai, Naoki Takehiro, Koshi Sekizawa, Hiroko Kimura, Atsuo Iio
  • Publication number: 20080160375
    Abstract: It is a main object of the present invention to provide a fuel cell catalyst in which a support for supporting a metal catalyst has electrical conductivity in itself and which can prevent agglomeration of the metal catalyst during long term use of the fuel cell. In the present invention, the object is achieved by providing a fuel cell catalyst for use in a cathode-side catalyst electrode layer of a solid polymer electrolyte fuel cell, comprising a metal catalyst and a perovskite-type complex oxide (ABO3).
    Type: Application
    Filed: February 24, 2006
    Publication date: July 3, 2008
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Koshi Sekizawa, Haruyuki Nakanishi
  • Patent number: 6238640
    Abstract: The invention provides a carbon monoxide conversion method for hydrogen-containing gas. The method comprises selective CO conversion in hydrogen-containing gas through contact of CO with steam and oxygen in the presence of a catalyst containing copper, alumina and zinc oxide.
    Type: Grant
    Filed: May 7, 1999
    Date of Patent: May 29, 2001
    Assignee: Idemitsu Kosan Co., Ltd.
    Inventors: Koichi Eguchi, Koshi Sekizawa, Sei-ichi Yano, Toshimasa Utaka, Hiromichi Arai